U.S. patent application number 16/894216 was filed with the patent office on 2020-09-24 for sprayable sunscreen compositions and methods.
This patent application is currently assigned to INOLEX INVESTMENT CORPORATION. The applicant listed for this patent is INOLEX INVESTMENT CORPORATION. Invention is credited to Rocco BURGO, Lorraine Lampe.
Application Number | 20200297604 16/894216 |
Document ID | / |
Family ID | 1000004872209 |
Filed Date | 2020-09-24 |
United States Patent
Application |
20200297604 |
Kind Code |
A1 |
BURGO; Rocco ; et
al. |
September 24, 2020 |
Sprayable Sunscreen Compositions and Methods
Abstract
Useful compositions are described herein that comprise a solvent
base comprising at least one non-aqueous solvent; at least one
sunscreen active ingredient that is a UV blocker and/or a UV
absorber; and a polymer reaction product of a random polymerization
of at least one organic diol, at least one polycarboxylic acid and
at least one polyol having at least three functional groups. Such
compositions are particularly useful in clear compositions
including sunscreens for personal care including spray sunscreen
formulations that are applied to and effective on wet skin, hair or
nails.
Inventors: |
BURGO; Rocco; (Mullica Hill,
NJ) ; Lampe; Lorraine; (West Chester, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
INOLEX INVESTMENT CORPORATION |
Wilmington |
DE |
US |
|
|
Assignee: |
INOLEX INVESTMENT
CORPORATION
Wilmington
DE
|
Family ID: |
1000004872209 |
Appl. No.: |
16/894216 |
Filed: |
June 5, 2020 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14671782 |
Mar 27, 2015 |
10709650 |
|
|
16894216 |
|
|
|
|
61971370 |
Mar 27, 2014 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 8/33 20130101; A61K
8/85 20130101; A61K 8/345 20130101; A61K 8/34 20130101; A61Q 17/04
20130101; A61K 8/86 20130101; A61K 8/31 20130101; A61K 8/40
20130101; A61K 8/375 20130101; A61K 8/35 20130101; A61K 2800/31
20130101 |
International
Class: |
A61K 8/40 20060101
A61K008/40; A61Q 17/04 20060101 A61Q017/04; A61K 8/33 20060101
A61K008/33; A61K 8/35 20060101 A61K008/35; A61K 8/34 20060101
A61K008/34; A61K 8/85 20060101 A61K008/85; A61K 8/31 20060101
A61K008/31; A61K 8/37 20060101 A61K008/37; A61K 8/86 20060101
A61K008/86 |
Claims
1. A composition, comprising: a solvent base comprising at least
one non-aqueous solvent; at least one sunscreen active ingredient
that is a UV blocker and/or a UV absorber; and a polymer reaction
product of a random polymerization of at least one organic diol, at
least one polycarboxylic acid and at least one polyol having at
least three functional groups.
2. The composition according to claim 1, wherein the at least one
non-aqueous solvent is an organic alcohol of about 1 to about 10
carbon atoms; an alkylene glycol; a polymeric alkylene glycol; a
branched chain hydrocarbon of about 6 to about 22 carbon atoms; an
alkyl ester or alkyl ether of an organic alcohol, an alkylene
glycol, a branched chain hydrocarbon of about 6 to about 22 carbon
atoms or a polymeric alkylene glycol; an alkyl ether or an alkyl
ester; or combinations thereof.
3. The composition according to claim 2, wherein the non-aqueous
solvent comprises ethanol and/or a branched chain hydrocarbon of
about 6 to about 22 carbon atoms.
4. The composition according to claim 2, wherein the non-aqueous
solvent is an alkylene glycol or a polymeric alkylene glycol
selected from the group consisting of polypropylene glycol,
polyethylene glycol and copolymers thereof; ethylene glycol;
propylene glycol; butylene glycol; pentylene glycol; hexylene
glycol; a diglycol; dodecane; a branched chain hydrocarbon of about
1 to about 22 carbon atoms.
5. The composition according to claim 2, wherein the non-aqueous
solvent is a dimethyl ether or a diethyl ether.
6. The composition according to claim 1, wherein solvent base is at
least about 35% to about 95% by weight of the composition.
7. The composition according to claim 6, wherein at least about 85%
to about 100% of the solvent base is the non-aqueous solvent.
8. The composition according to claim 6, wherein the solvent base
is about 35% to about 65% of the composition.
9. The composition according to claim 8, wherein at least about 95%
to about 100% of the solvent base is the non-aqueous solvent.
10. The composition according to claim 1, wherein the composition
comprises about 0.5% to about 75% of the at least one sunscreen
active ingredient.
11. The composition according to claim 10, wherein the composition
comprises about 5% to about 70% of the at least one sunscreen
active ingredient.
12. The composition according to claim 11, wherein the composition
comprises about 20% to about 50% of the at least one sunscreen
active ingredient.
13. The composition according to claim 1, wherein the at least one
sunscreen active ingredient is selected from the group consisting
of octocrylene, oxybenzone, octisalate, homosalate, avobenzone,
octinoxate, and combinations thereof.
14. The composition according to claim 1, wherein the at least one
organic diol is 1,3-pentanediol, 2,2,4-trimethyl-1,3-pentanediol,
1,2-pentane diol, 2-methyl-1,3-propanediol and combinations
thereof.
15. The composition according to claim 14, wherein the at last one
organic diol is 2,2,4-trimethyl-1,3-pentane diol.
16. The composition according to claim 1, wherein the at least one
polycarboxylic acid is selected from the group consisting of
propanedioic acid; decanedioic acid; pentanedioic acid; hexanedioic
acid; heptanedioic acid; octanedioic acid; nonanedioic acid; and
decanedioic acid.
17. The composition according to claim 16, wherein the at least one
polycarboxylic acid is a diacid.
18. The composition according to claim 17, wherein the at least one
polycarboxylic acid is hexanedioic acid.
19. The composition according to claim 1, wherein the at least one
polyol is selected from the group consisting of dimerdiol,
trimethylolpropane, ditrimethylolpropane, glycerol, 1,2,3-propane
triol, and combinations thereof.
20. The composition according to claim 1, wherein the polymer is a
random polymer of 2,2,4-trimethyl-1,3-pentane diol, heptanedioic
acid and glycerol.
21. A method of preparing a sunscreen composition having a solvent
base, comprising combining: (a) a non-aqueous solvent system; (b) a
polyester polymer formed as an esterification reaction product of
at least one polycarboxylic acid, at least one organic diol and at
least one polyol; and (c) at least one sunscreen active ingredient
that is a UV blocker and/or a UV absorber.
22. The method according to claim 21, wherein the non-aqueous
solvent system comprises an alcohol of about 1 to about 10 carbon
atoms and at least one branched chain hydrocarbon of about 6 to
about 22 carbon atoms
23. The method according to claim 22, wherein the at least one
branched hydrocarbon comprises an isoparaffin and/or an
isoalkane.
24. The method according to claim 21, wherein the sunscreen active
ingredient is a UV absorber that is a UV filtering compound.
25. The method according to claim 21, further comprising combining
(d) at least one ester oil in the composition.
26. The method according to claim 21, wherein the at least one
polycarboxylic acid, at least one organic diol and at least one
polyol are reacted so as to have a ratio of organic
diol:polycarboxylic acid:polyol of about 5:5:1 to about
25:25:1.
27. The method according to claim 25, wherein the ratio of organic
diol:polycarboxylic acid:polyol is about 10:10:1.
28. The method according to claim 21, wherein the esterification
occurs at about 100.degree. C. to about 260.degree. C.
29. The method according to claim 21, wherein the esterification
occurs at about 760 mm Hg to about 1 mm Hg.
30. A composition suitable for use in a personal care formulation,
comprising at least one sunscreen active ingredient that is a UV
blocker and/or a UV absorber; and a polymer reaction product of a
random polymerization of at least one polycarboxylic acid, at least
one organic diol and at least one polyol, wherein a ratio of
organic diol:polycarboxylic acid:polyol is about 5:5:1 to about
25:25:1.
31. A method of increasing a sunscreen protection factor of a
personal care formulation having at least one sunscreen active
ingredient that is a UV blocker and/or a UV absorber, the method
comprising providing to the personal care formulation a polyester
polymer formed as an esterification reaction product of at least
one polycarboxylic acid, at least one organic diol and at least one
polyol.
32. The method according to claim 31, wherein the personal care
formulation is a sprayable sunscreen and the formulation comprises
a non-aqueous solvent system.
33. The method according to claim 32, wherein the non-aqueous
solvent system comprises an alcohol of about 1 to about 10 carbon
atoms and at least one branched chain hydrocarbon of about 6 to
about 22 carbon atoms.
34. The method according to claim 31, wherein the formulation
further comprises at least one ester oil in the composition.
35. The method according to claim 31, wherein the at least one
polycarboxylic acid, at least one organic diol and at least one
polyol are reacted so as to have a ratio of organic
diol:polycarboxylic acid:polyol of about 5:5:1 to about
25:25:1.
36. The method according to claim 35, wherein the ratio of organic
diol:polycarboxylic acid:polyol is about 10:10:1.
37. The method according to claim 31, wherein the esterification
occurs at about 100.degree. C. to about 260.degree. C. and at about
760 mm Hg to about 1 mm Hg.
38. A method of increasing water resistance of a personal care
formulation having at least one sunscreen active ingredient that is
a UV blocker and/or a UV absorber, the method comprising providing
to the personal care formulation a polyester polymer formed as an
esterification reaction product of at least one polycarboxylic
acid, at least one organic diol and at least one polyol.
39. The method according to claim 38, wherein the personal care
formulation is a sprayable sunscreen and the formulation comprises
a non-aqueous solvent system.
40. The method according to claim 38, wherein the non-aqueous
solvent system comprises an alcohol of about 1 to about 10 carbon
atoms and at least one branched chain hydrocarbon of about 6 to
about 22 carbon atoms.
41. The method according to claim 38, wherein the formulation
further comprises at least one ester oil in the composition.
42. The method according to claim 38, wherein the at least one
polycarboxylic acid, at least one organic diol and at least one
polyol are reacted so as to have a ratio of organic
diol:polycarboxylic acid:polyol of about 5:5:1 to about
25:25:1.
43. The method according to claim 42, wherein the ratio of organic
diol:polycarboxylic acid:polyol is about 10:10:1.
44. The method according to claim 38, wherein the esterification
occurs at about 100.degree. C. to about 260.degree. C. and at about
760 mm Hg to about 1 mm Hg.
45. A method of reducing a whitening effect of a personal care
formulation having at least one sunscreen active ingredient that is
a UV blocker and/or a UV absorber when applied to wet skin, the
method comprising providing to the personal care formulation a
polyester polymer formed as an esterification reaction product of
at least one polycarboxylic acid, at least one organic diol and at
least one polyol.
46. The method according to claim 45, wherein the personal care
formulation is a sprayable sunscreen and the formulation comprises
a non-aqueous solvent system.
47. The method according to claim 45, wherein the non-aqueous
solvent system comprises an alcohol of about 1 to about 10 carbon
atoms and at least one branched chain hydrocarbon of about 6 to
about 22 carbon atoms.
48. The method according to claim 45, wherein the formulation
further comprises at least one ester oil in the composition.
49. The method according to claim 45, wherein the at least one
polycarboxylic acid, at least one organic diol and at least one
polyol are reacted so as to have a ratio of organic
diol:polycarboxylic acid:polyol of about 5:5:1 to about
25:25:1.
50. The method according to claim 50, wherein the ratio of organic
diol:polycarboxylic acid:polyol is about 10:10:1.
51. The method according to claim 45, wherein the esterification
occurs at about 100.degree. C. to about 260.degree. C. and at about
760 mm Hg to about 1 mm Hg.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S.
application Ser. No. 14,671,782, filed Mar. 27, 2015, which claims
the benefit under 35 U.S.C. .sctn. 119(e) of U.S. Provisional
Patent Application No. 61/971,370, filed Mar. 27, 2014, entitled,
"Sprayable Sunscreen Compositions and Methods," all of which are
herein incorporated by reference in their entirety for all
purposes.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention relates to the field of sunscreen active
personal care formulations, particularly those that are applied to
mammal skin, hair or nails that are damp, moist or otherwise wet
surfaces, and more particularly to sprayable sunscreen
formulations.
Description of Related Art
[0003] The electromagnetic radiation (light energy) within the
ultraviolet (UV) spectrum that reaches the earth's surface falls
within the wavelength range of approximately 290 to 400 nanometers
(nm). The portion of the spectrum that is responsible for erythema
(sunburn) of skin is within the range of about 290 to 320 nm, and
is referred to as UV-B. More recently, research has shown that not
only sunlight energy within the UV-B range can be harmful to skin,
but lower energy, longer wavelengths (known as UV-A) with a range
of 320 to 400 nm may also be problematic. UV-C radiation (from
about 200 to 290 nm) can also be problematic and is associated with
artificial tanning, such as through sun lamps or tanning beds.
[0004] UV-A has been shown to penetrate the skin more deeply than
UV-B. In studies which have occurred over the past two decades, it
has been shown that the effects of prolonged UV-A exposure can
result in premature skin aging, wrinkling, and has been implicated
as a potential initiator for the development of skin cancers. UV-A
damages skin cells in the basal layer of the epidermis
(keratinocytes) where most skin cancers occur. In addition to
harming skin, UV radiation can also cause damage to other areas,
such as hair, causing it to change color and impacting
color-treated hair as well, creating damage to the physical
character of the hair and loss of shine or manageability.
[0005] Topical photoprotective treatments, such as sunscreens, have
been developed to mitigate or prevent skin or hair damage.
Sunscreen formulations are applied topically to protect against UV
induced skin damage and are prepared in various forms, including
creams, lotions, and sprays. Conventional sunscreen formulators
will typically incorporate organic chemical compounds that
chemically absorb UV radiation (organic UV filters) and inorganic
compounds that in addition to absorbing, also physically scatter
and/or reflect the radiation (UV blockers) into the sunscreen
product.
[0006] For sunscreens to be used effectively, they need to be
applied evenly and as directed. Misuse of sunscreens by improper or
inconsistent application can result in grave problems. Ineffective
application due to defects in the formulation's ability to be
applied properly can be similarly problematic. Users may feel they
are protected from the sun's rays and may take lesser steps to
avoid exposure by physically covering the body by clothing or
shade. Misapplication or under application can also result because
the user may feel that the sunscreen product is aesthetically
unpleasing or too greasy to the skin (blocking pores, etc.).
[0007] Historically, sunscreens were formulated predominantly to
prevent sunburn and associated acute discomfort. Consequently, they
included primarily UV-B filters and UV blockers. The ability of a
given sunscreen to protect against sunburn is communicated to a
consumer by use of the sun protection factor ("SPF") system. SPF is
an in vivo laboratory measurement of the effectiveness of sunscreen
in preventing sunburn. It is a numerical value. The higher the SPF,
the more protection a sunscreen offers against UV-B. The SPF is
further defined, and the detailed testing procedures are provided
in United States Food and Drug Administration ("FDA") publication
"Sunscreen Drug Products for Over-the-Counter Human Use"; Final
Monograph; 21CFR Parts 310, 352, 700 and 740. Federal Register 64
(98) May 21, 1999. pp. 27666-27693, the contents of which are
incorporated herein by reference.
[0008] Attempts have been made to develop sunscreens that include
filters that also absorb UV-A radiation. In the U.S., the approved
organic UV-A filter is limited to butyl methoxydibenzoylmethane
(avobenzone or AVO) due to statutory requirements. AVO has been
shown to degrade in the presence of sunlight by photolytic
mechanisms, with the products of photodegradation being less
effective at absorbing UV-A radiation than the parent compound.
This means that protection against UV-A is reduced from time of
initial application and upon subsequent exposure to sunlight when
AVO is used as an UV-A filter. Photodegradation is particularly
pronounced when AVO is used in combination with 2-ethylhexyl
(2E)-3-(4-methoxyphenyl)prop-2-enoate (octylmethoxycinnamate,
octinoxate, OMC.)
[0009] Regulatory activity has centered on the labeling of
sunscreens and the development of better ways to convey to
consumers a sunscreen's ability to not only protect against
sunburn, but to also protect against UV-A damage. In 2007, the FDA
published proposed amendments to the monograph for sunscreen drug
products for over-the-counter human use. Within the amendments are
revisions to the test-procedures for evaluating the efficacy of
sunscreen products. In addition to SPF, the revisions include
provisions for evaluating UV-A protection, as well as
photostability. The FDA has also proposed a four-star UV-A
protection rating system based on in vivo and in vitro testing
methods. These values are further defined, and the detailed testing
procedures are provided in, "U. S. Food and Drug Administration.
Sunscreen Drug Products for Over-the-Counter Human Use"; Proposed
Amendment of Final Monograph; Proposed Rule; 21CFR Parts 347 and
352. Federal Register 72 (165) Aug. 27, 2007. 49070-4912, the
contents of which are incorporated herein by reference.
[0010] The European Cosmetics Association ("COLIPA") has also
published guidelines and testing procedures relating to UV-A
protection. In these documents, additional numerical parameters
have been defined such as the in vitro SPF, and the in vitro UV-A
protection factor. These parameters are further defined and the
detailed testing procedures are provided in "Colipa Project Team
IV, in-vitro Photoprotection Methods, Method for the in-vitro
Determination of UVA Protection Provided by Sunscreen Products,
Guideline, 2007", the contents of which are incorporated herein by
reference.
[0011] Additional parameters have been defined, such as the
UV-A/UV-B ratio, and the critical wavelength. The UV-A/UV-B ratio
describes the performance of a sunscreen in the UV-A in relation to
its performance in the UV-B range. It is calculated as the ratio
between the areas under the UV-A and UV-B parts of the extinction
curve, both areas being normalized to the range of wavelengths
involved. The UV-A/UV-B ratio is further defined and detailed
testing procedures are provided in "Measurement of UV-A/UV-B ratio
according to the Boots Star rating system," (2008 revision), Boots
UK Limited, Nottingham, NG2 3AA, UK (January 2008), the contents of
which are incorporated herein by reference.
[0012] The critical wavelength is given as the upper limit of the
spectral range from 290 nm on, within which 90% of the area under
the extinction curve of the whole UV-range between 290 nm and 400
nm is covered. If that wavelength is 370 nm or greater, the product
is considered "broad spectrum," which denotes balanced protection
throughout the UV-B and UV-A ranges. The critical wavelength is
further defined and detailed testing procedures are provided in
Diffey B L, et al, "In-vitro assessment of the broad-spectrum
ultraviolet protection of sunscreen products," J Amer Acad Dermatol
43:1024-35, 2000, the contents of which are incorporated herein by
reference.
[0013] It has been discovered that certain sunscreen chemicals are
absorbed across the skin and enter into systemic circulation.
Particular attention has been given to the filter
benzophenone-3.
[0014] With such guidelines in mind, most sunscreen formulators
aspire to develop a sun care product that, when tested, obtains
higher values for some or all of the numerical parameters described
above, and thereby achieves an improvement over current sunscreen
technology, and which includes polymeric filters to mitigate skin
penetration. There remains also a need in the art for new
ingredients, such as formulation ingredients and polymers, that can
be used to better formulate photoprotective products so that
properties such as photostability, pleasant aesthetics, higher SPF,
and increased UV-A protection may be realized as well as
optimized.
[0015] Sunscreens and other products having sunscreen protection,
applicable to the skin, scalp, lips and/or hair while best applied
before exposure, typically require re-application. They are applied
as creams, lotions, or other cosmetic formulations (lip balm or
liquid foundation for example). Most use is for exposure to the sun
outdoors, for example, walking, participating in sports, running,
swimming, beach activities, and the like. As noted above, while
users do not generally like the use of a greasy formulation,
creating a resistance to use, and there is a desire for a more
"dry"--feeling formulation on application, it is also a problem
when applied sunscreen products in whatever form are contacted with
moisture--either from perspiration due to physical activity, from
rain or from swimming, etc. The user also knows and desires (and
good protection dictates) that if the product washes off, it will
require re-application, which is difficult to do when wet, or can
become greasy to the surface of the skin when wet, causing users to
not re-apply either because they believe it will not be effective,
because it feels oily or greasy or because it simply drips off or
causes blotchy or spotty application on the skin.
[0016] Clearer formulations are preferred for use also by users, so
that it does not appear they are wearing sunscreen when in use. If
the sunscreen starts to smear, wipe off, drip or otherwise separate
off the skin, it can appear white and/or clumped in oily-looking
patches on the damp skin. This is not only an aesthetically
undesirable result, it can discourage use and/or re-application
when the skin becomes wet, leading to no protection and harm to the
skin or hair.
[0017] The clear products are generally "anhydrous," meaning they
have very little water in them and preferably less than about 5%
water. Such formulations come in "clear" products like gels, clear
lotions, or sprayable sunscreen products. In an anhydrous
formulation, the active and inactive ingredients are generally in a
solution form with a base solvent, such as an organic alcohol.
Sprayable sunscreens based on alcohol solutions are a growing
global product trend. The popularity of sprayable sunscreen
formulations derives from their ease of use and application. When
in an active setting, they take little time to apply, dry quickly
and typically do not exhibit the greasiness associated with
traditional sunscreen lotions and creams. In addition, they are
easier to put on another person or yourself, which is especially
useful for parents who need to apply sunscreen to themselves and to
their children. In a beach situation, they are also less likely to
have sand stuck in the lotion which is then rubbed into the
skin.
[0018] A recent development increasing this popularity, especially
for parents, is sprayable sport sunscreen products, which are
intended to be sprayed directly onto wet skin, offer an advantage
of more even coverage compared to traditional lotions and creams,
and provide a more aesthetically pleasing look and feel. Further,
when applied and working correctly, perform without a loss of
efficacy in terms of broad spectrum sun protection and water
resistance.
[0019] U.S. Pat. No. 8,778,313 B2 is directed to improving
sunscreens for enhanced SPF and UV-A and UV-B protective sunscreens
for spray use that incorporate at least one ester-terminated
poly(ester amide) polymer in combination with a combined sunscreen
protection system.
[0020] U.S. Patent Application Publication No. 2014/0017186 A1 is
directed to a sprayable sunscreen formulation having a co-polymer
formed from a vinyl monomer and an acid-functional monomer, with an
optional different third vinyl monomer.
[0021] U.S. Patent Application Publication No. 2014/0348757 A1
discloses a sprayable alcohol-based sunscreen formulation using a
film-forming polymer comprising shellac.
[0022] U.S. Patent Publication No. 2014/0170090 A1 teaches a
sunscreen composition having avobenzone in an amount for providing
UV-A protection, an alcohol, and an antioxidant such as a vitamin,
and further may include a water-penetrating polymer which is
hydrophobic such as an alkyl maleate/acrylate copolymer.
[0023] While it is important to continue to improve sunscreens in
sprayable form that stay on the user better and provide desirable
properties, those in the art are focusing on developing various
combinations of sunscreen actives, or other additives as well as
experimenting with different base polymers as noted in the patent
and patent publications described above. However, there is still a
need in the art for an improved formulation.
[0024] The applicant herein has provided film former technology
into the sun care market for many years, including various polymers
based upon variations in polyester technology, marketed under the
Lexorez.RTM. brand. However, a need in the art still exists for
vehicles and formulations to improve on the performance of clear
anhydrous formulations, such as sprayable sunscreen
formulations.
[0025] Alcohol-based spray sunscreens are typically simple
solutions in ethanol of organic UV filters, emollients, and film
formers. A major disadvantage of many existing sprayable sunscreens
products in this area of the art is that when sprayed on wet skin,
the oily components rapidly fall out of solution and coalesce. This
then creates an aesthetically displeasing whitening due to the
scattering of light at the phase interfaces. See FIG. 1.
[0026] Another negative result encountered is that a feeling of
oiliness or greasiness on the skin surface is experienced due to
coalesced filters and emollients. Consumers have historically
demanded that sunscreens be as dry feeling as possible as noted
above, and a sunscreen that feels greasy may be misused by
under-applied. This results in insufficient protection against
damaging UV rays.
[0027] Another negative aesthetic effect from such sprays is a
residual shininess on the skin primarily caused by non-uniformity
of the emollients and filters.
[0028] So as not to exhibit these deficiencies, an ideal sprayable
or other clear-type anhydrous sunscreen should spread out quickly
on the skin into a uniform film. Additionally, in sprayable
formulations, the emollients and filters should not drop out of
solution and coalesce.
[0029] There is a need in the art for solvent-based compositions,
such as sprayable or other solvent-based sunscreen formulations,
that eliminates the above-noted deficiencies in the art, and
achieves a dry feel, an aesthetically pleasing appearance and feel
on the skin and a uniform film application, particularly when the
skin is exposed to wetness or moisture.
BRIEF SUMMARY OF THE INVENTION
[0030] The invention includes a composition, comprising: a solvent
base comprising at least one non-aqueous solvent; at least one
sunscreen active ingredient that is a UV blocker and/or a UV
absorber; and a polymer reaction product of a random polymerization
of at least one organic diol, at least one polycarboxylic acid and
at least one polyol having at least three functional groups. In one
preferred embodiment, it is also advantageous to include emollients
such as esters in the compositions.
[0031] The at least one non-aqueous solvent may be an organic
alcohol of about 1 to about 10 carbon atoms; an alkylene glycol; a
polymeric alkylene glycol; a branched chain hydrocarbon of about 6
to about 22 carbon atoms; an alkyl ester or alkyl ether of an
organic alcohol, an alkylene glycol, a branched chain hydrocarbon
of about 6 to about 22 carbon atoms or a polymeric alkylene glycol;
an alkyl ether or an alkyl ester; or a combination thereof. In one
embodiment, the non-aqueous solvent is an organic alcohol selected
from the group consistent of ethanol, propanol, isopropanol,
butanol, isobutanol, pentanol, isopentanol and/or hexanol. In a
further embodiment, the non-aqueous solvent is an alkylene glycol
or a polymeric alkylene glycol selected from the group consisting
of polypropylene glycol, polyethylene glycol and copolymers
thereof; ethylene glycol; propylene glycol; butylene glycol;
pentylene glycol; hexylene glycol; a diglycol; dodecane;
isododecane or any of the branched chain hydrocarbons such as those
available from ExxonMobil under the trade name Isopar.TM.; and/or a
diglycol. The non-aqueous solvent may also be dimethyl ether or a
diethyl ether.
[0032] The solvent base may be present in an amount of at least
about 35% to about 95% by weight of the composition, preferably
wherein at least about 85% to about 100% of the solvent base is the
non-aqueous solvent. More preferably, the solvent base may be
present in the composition in an amount that is about 35% to about
65% of the composition, and wherein preferably at least about 95%
to about 100% of the solvent base is the non-aqueous solvent.
[0033] In one embodiment, the at least one sunscreen active
ingredient is present in an amount of about 0.5% to about 75% of
the composition, more preferably about 5% to about 70% of the at
least one sunscreen active ingredient is present in the
composition, and most preferably about 20% to about 50% of the at
least one sunscreen active ingredient is present in the
composition.
[0034] The at least one sunscreen active ingredient may be selected
from the group consisting of octocrylene, oxybenzone, octisalate,
homosalate, avobenzone, octinoxate, and combinations thereof.
[0035] The polymer reaction product may be derived from the
esterification of at least one organic diol, at least one
polycarboxylic acid, and at least one polyol. The at least one
organic diol may be 1,3-pentanediol,
2,2,4-trimethyl-1,3-pentanediol, 1,2-pentane diol,
2-methyl-1,3-propanediol and combinations thereof, and is most
preferably 2,2,4-trimethyl-1,3-pentane diol.
[0036] The at least one polycarboxylic acid may be selected from
the group consisting of propanedioic acid; decanedioic acid;
pentanedioic acid; hexanedioic acid; heptanedioic acid; octanedioic
acid; nonanedioic acid; and decanedioic acid, and combinations
thereof. In one embodiment, the at least one polycarboxylic acid is
a diacid, and is preferably hexanedioic acid
[0037] The at least one polyol may be selected from the group
consisting of dimerdiol, trimethylolpropane, ditrimethylolpropane,
glycerol, 1,2,3-propane triol, and combinations thereof. The
polymer is most preferably a random polymer of
2,2,4-trimethyl-1,3-pentane diol, heptanedioic acid and
glycerol.
[0038] The invention further includes a method of preparing a
sunscreen composition having a solvent base, comprising combining:
(a) a non-aqueous solvent system; (b) a polyester polymer formed as
an esterification reaction product of at least one polycarboxylic
acid, at least one organic diol and at least one polyol; and (c) at
least one sunscreen active ingredient that is a UV blocker and/or a
UV absorber. In one embodiment, the non-aqueous solvent system
comprises an alcohol of about 1 to about 10 carbon atoms and at
least one branched chain hydrocarbon of about 6 to about 22 carbon
atoms, wherein the at least one branched chain hydrocarbon may
comprise an isoparaffin and/or an isoalkane.
[0039] The sunscreen active ingredient is preferably a UV absorber
that is a UV filtering compound. The method may further comprises
combining (d) at least one ester oil in the composition. In the
method, the at least one branched chain hydrocarbon may comprise an
isoparaffin and/or an isoalkane. The at least one polycarboxylic
acid, at least one organic diol and at least one polyol are
preferably reacted so as to have a ratio of organic
diol:polycarboxylic acid:polyol of about 5:5:1 to about 25:25:1,
and more preferably about 10:10:1. The esterification preferably
occurs at about 100.degree. C. to about 260.degree. C. and at about
760 mm Hg to about 1 mm Hg.
[0040] The invention also includes in one embodiment thereof a
composition suitable for use in a personal care formulation,
comprising at least one sunscreen active ingredient that is a UV
blocker and/or a UV absorber; and a polymer reaction product of a
random polymerization of at least one polycarboxylic acid, at least
one organic diol and at least one polyol, wherein a ratio of
organic diol:polycarboxylic acid:polyol is about 5:5:1 to about
25:25:1.
[0041] Also within the scope of the invention hereof, is a method
of increasing a sunscreen protection factor of a personal care
formulation having at least one sunscreen active ingredient that is
a UV blocker and/or a UV absorber, the method comprises providing
to the personal care formulation a polyester polymer formed as an
esterification reaction product of at least one polycarboxylic
acid, at least one organic diol and at least one polyol. The
personal care formulation may be a sprayable sunscreen and the
formulation preferably comprises a non-aqueous solvent system. The
non-aqueous solvent system in one preferred embodiment comprises an
alcohol of about 1 to about 10 carbon atoms and at least one
branched chain hydrocarbon of about 6 to about 22 carbon atoms, and
may further comprises at least one ester oil in the composition.
The at least one polycarboxylic acid, at least one organic diol and
at least one polyol are preferably reacted so as to have a ratio of
organic diol:polycarboxylic acid:polyol of about 5:5:1 to about
25:25:1, and more preferably about 10:10:1. In the method, the
esterification occurs preferably at about 100.degree. C. to about
260.degree. C. and at about 760 mm Hg to about 1 mm Hg.
[0042] A further method is provided in the invention hereof, which
is a method of increasing water resistance of a personal care
formulation having at least one sunscreen active ingredient that is
a UV blocker and/or a UV absorber, the method comprising providing
to the personal care formulation a polyester polymer formed as an
esterification reaction product of at least one polycarboxylic
acid, at least one organic diol and at least one polyol. In the
method, the personal care formulation may be a sprayable sunscreen
and the formulation may comprise a non-aqueous solvent system,
including one that preferably comprises an alcohol of about 1 to
about 10 carbon atoms and at least one branched chain hydrocarbon
of about 6 to about 22 carbon atoms. The formulation may further
comprise at least one ester oil. The at least one polycarboxylic
acid, at least one organic diol and at least one polyol are
preferably reacted so as to have a ratio of organic
diol:polycarboxylic acid:polyol of about 5:5:1 to about 25:25:1,
and preferably about 10:10:1. The esterification preferably occurs
at about 100.degree. C. to about 260.degree. C. and at about 760 mm
Hg to about 1 mm Hg.
[0043] The invention also includes a method of reducing a whitening
effect of a personal care formulation having at least one sunscreen
active ingredient that is a UV blocker and/or a UV absorber when
applied to wet skin, the method comprising providing to the
personal care formulation a polyester polymer formed as an
esterification reaction product of at least one polycarboxylic
acid, at least one organic diol and at least one polyol. In the
method, the personal care formulation may be a sprayable sunscreen
and the formulation may comprise a non-aqueous solvent system,
including one that preferably comprises an alcohol of about 1 to
about 10 carbon atoms and at least one branched chain hydrocarbon
of about 6 to about 22 carbon atoms. The formulation may further
comprise at least one ester oil. The at least one polycarboxylic
acid, at least one organic diol and at least one polyol are
preferably reacted so as to have a ratio of organic
diol:polycarboxylic acid:polyol of about 5:5:1 to about 25:25:1,
and preferably about 10:10:1. The esterification preferably occurs
at about 100.degree. C. to about 260.degree. C. and at about 760 mm
Hg to about 1 mm Hg.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0044] The foregoing summary, as well as the following detailed
description of preferred embodiments of the invention, will be
better understood when read in conjunction with the appended
drawings. For the purpose of illustrating the invention, there is
shown in the drawings embodiments which are presently preferred. It
should be understood, however, that the invention is not limited to
the precise arrangements and instrumentalities shown. In the
drawings:
[0045] FIG. 1 is an enlarged photographic representation of the
appearance of whitening from a prior art sprayable sunscreen;
[0046] FIG. 2 is a photographic representation of a prior art
sunscreen having oily component coalescence on skin;
[0047] FIG. 3 is a photographic representation of a Control and
Inventive Example after the test described in Example 1;
[0048] FIG. 4 is a photographic representation of the Control
formulation of Example 1 on sandpaper;
[0049] FIG. 5 is a photographic representation of the inventive
Example formulation of Example 1 on sandpaper; and
[0050] FIG. 6 is a photographic representation of the Control
formulation of Example 1 on human skin;
[0051] FIG. 7 is a photographic representation of the inventive
Example formulation of Example 1 on human skin;
[0052] FIG. 8 is a schematic representation illustrating the
operation of a Skin Glossymeter used in Example 2; and
[0053] FIG. 9 is a graphical representation of a comparison of
properties described in Example 2 using an existing spray sunscreen
formulation for wet skin and the Inventive Example from Example 1
in side-by-side comparison tests on human subjects;
DETAILED DESCRIPTION OF THE INVENTION
[0054] The skin is a good barrier and is hydrophobic. As a result,
water is not evenly dispersed when skin is wet. On wet skin, high
local concentrations of water exist on the surface in the form of
droplets. When using a sprayable-type sunscreen, when the sunscreen
interacts with the water droplets, its composition is changed
significantly. If the oily components (emollients, UV filters and
polymers) of the sunscreen are very water intolerant, they are
pushed out of the solution by the water and coalesce. "Water
intolerant" herein refers to the rate and amount of coalescence
that occurs when the sunscreen formulation comes in contact with
the water. The coalescence results in a whitening effect due to the
difference in refractive index between the oil and water phases.
FIG. 1 shows a prior art wet-skin, alcohol-based spray sunscreen
sprayed on wet skin. FIG. 2 shows a prior art wet-skin,
alcohol-based spray sunscreen sprayed on 600 grit wet/dry
sandpaper. These Figures illustrate this typical prior art
sunscreen application effect.
[0055] Thus, applicants have determined that for an alcohol-based
sunscreen to remain clear when sprayed on wet skin, water tolerance
should be maximized. Applicants evaluated factors such as Hansen
solubility parameters, density, and other similar properties to
evaluate the effect of the inclusion of polyester film formers in
sunscreen formulations to increase water tolerance.
[0056] As a result of this research, applicants have developed a
formulation polymer that, among other things, significantly
improves the water tolerance of alcohol-based formulations,
including particularly spray sunscreen formulations, and also
provides the benefit of excellent water resistance.
[0057] The compositions of the present invention are useful as
sunscreen-containing products that have a dry feel and/or are
substantially "clear" (meaning they are formulated for virtually no
color when used on the skin) and/or are applied as a spray and/or
employed in cosmetics having sunscreens, that minimize an
aesthetically unappealing oily or greasy feel in use and which
resist loss or separation of formulation components when applied on
a wet keratinous surface such as skin or hair. They are especially
suitable for, but not limited to, spray sunscreen formulations for
use on wet human skin.
[0058] The compositions include at least one solvent, preferably a
non-aqueous solvent; at least one sunscreen active ingredient that
is a UV blocker and/or a UV absorber; and a polymer reaction
product of a random polymerization of at least one organic diol, at
least one dicarboxylic acid and at least one polyol having at least
three functional groups. Such compositions may also include various
optional cosmetic and/or sunscreen formulation components as are
known in the art or to be developed as described further below.
[0059] As noted elsewhere herein, the compositions preferably are
substantially anhydrous, but need not be fully non-aqueous solvent
based, and so may include some water. Preferably, the composition
has at least about 35% to about 95% of a solvent base, of which at
least about 85% up to about 100% of the solvent base is a
non-aqueous solvent. More preferably there is about 35% to about
65% of a solvent base, of which about 95% to about 100% is a
non-aqueous solvent. While water is acceptable (preferably more
than about 0 up to about 15%), in preferred embodiments, water is
omitted or is only a minor component of the solvent base.
[0060] Suitable non-aqueous solvents include, but are not limited
to organic alcohols, such as of about 1 to about 10 carbon atoms,
including, but not limited to methanol, ethanol, propanol,
isopropanol, butanol, isobutanol, pentanol, isopentanol, hexanol,
and the like; polymeric glycols, such as polypropylene glycols or
polyethylene glycols (PEGs) of varying length, and copolymers of
such polymeric glycols, glycol compounds such as ethylene glycol,
propylene glycol, butylene glycol, pentylene glycol, hexylene
glycol, diglycols and similar compounds, sorbitols or isosorbitols;
branched chain hydrocarbons of about 6 to about 22 carbon atoms,
such as isoalkanes and isoparaffins of varying lengths (e.g.,
C10-13, C13-14, C13-16 isoparaffins or C8-13 or C9-12 isoalkanes)
such as those available from ExxonMobil under the name Isopar.TM.,
isoolefins, isododecanes and the like; alkyl esters or alkyl ethers
of any of the above alcohol, glycol or hydrocarbon compounds;
volatile solvents such as ether solvents, for example, dimethyl
ethers or diethyl ethers. Use of alcohols preferably includes of
use denatured alcohol as commonly used in human skin care products
and spray formulations.
[0061] The solvent base, including the non-aqueous solvent acts as
a carrier compound for the sunscreen active agents and other
components in the compositions herein.
[0062] In the composition, the at least one sunscreen active
ingredient may be any acceptable a UV blocker and/or a UV absorber
in whatever form that is useful in the desired sunscreen product
preferably intended for initial use and/or re-application on skin
having or subject to moisture, perspiration, water and the like,
including but not limited to solvent-based or solvent/water-based
lotions, cream, spray or other form of sunscreen products,
cosmetics or hair care products having sunscreen in whatever form
and similar products without intending to be limiting, even though
the invention is especially useful in spray on sunscreen and hair
products having sunscreens wherein the user has a skin or hair
surface that is moist, damp, wet, etc. Such sunscreen actives can
be an organic or inorganic compound, a UV-absorbing polymer, or the
like. UV-absorbing polymers are disclosed, for example, in
applicant's co-pending U.S. Publication No. 2011/0104078 A1,
incorporated herein, in relevant part, by reference.
[0063] Other suitable UV blocking and/or absorbing materials
include but are not limited to non-polymeric chemical UV filters,
such as, octyl triazone, diethylhexyl butamido triazone,
diethylamino hydroxybenzoyl hexyl benzoate, iscotrizinol,
dimethico-diethylbenzalmalonate, polysilicone-15,
isopentenyl-4-methoxycinnamate, ethylhexyl methoxycinnamate,
ethylhexyl triazone, p-aminobenzoic acid (PABA),
octyldimethyl-PABA, PEG-25 PABA, ethylhexyl dimethyl PABA,
methylene bis-benztriazolyl tetramethylbutylphenol, bisodium phenyl
dibenzimidazole tetrasulfonate, bis-ethylhexyloxyphenol
methoxyphenol triazine, phenylbenzimidazole sulfonic acid,
2-ethoxyethyl p-methoxycinnamate, benzophenone-8, benzophenone-5,
benzophenone-4, benzophenone-3, homomethyl salicylate, meradimate,
octocrylene, octyl methoxycinnamate, isoamyl p-methoxycinnamate,
oxybenzone, octisalate, homosalate, avobenzone, octinoxate, octyl
salicylate, sulisobenzone, trolamine salicylate, avobenzone,
terephthalylidene dicamphor sulfonic acid, camphor benzalkonium
methosulfate, phenylbenzimidazole sulfonic acid,
4-methylbenzylidene camphor, terephthalidene dicamphor sulfonic
acid, benzylidene camphor sulfonic acid, polyacrylamidomethyl
benzylidene camphor, 4-methylbenzylidene camphor, 3-benzylidene
camphor, ethylhexyl salicylate, bisoctrizole,
bis-ethylhexyloxyphenol methoxyphenol triazine, bisdisulizole
disodium, drometrizole trisiloxane, polysilicone-15, sodium
dihydroxy dimethoxy disulfobenzophenone, ethylhexyl triazone,
diethylamino hydroxybenzoyl hexyl benzoate, diethylhexyl butamido
triazone, dimethico-diethylbenzalmalonate, drometrizole
trisiloxane, as well as UV blockers such as titanium dioxide,
silicone-treated titanium dioxides, zirconium oxides, zinc oxide,
talc, cerium oxides, chromium oxides, cobalt oxides, iron oxides,
red petrolatum, and combinations of these materials
(filters/absorbers or blockers) together or with others as are
known or to be developed in the art.
[0064] Typically, such materials are used in combinations useful
for effect or synergy to achieve desired blocking or absorbing
combinations. The invention is more directed to maintaining such
materials and other additives in the compositions, however, and so
it is not intended that the sunscreen active ingredient(s) used are
limited.
[0065] The sunscreen active agent(s) is/are preferably present in
an amount effective to provide sunscreen protection consistent with
the desired SPF of the composition and can be from about 0.5% to
about 75% of the composition, preferably about 5% to about 70% of
the composition, and most preferably about 20% to about 50% of the
composition, although the amount may be adjusted for desired end
effects and based on the selected active ingredients as is known in
the art.
[0066] The a novel polymers used in the compositions herein are
preferably one or more reaction products of random polymerization
of at least one organic diol, at least one dicarboxylic acid and at
least one polyol having at least three functional groups, and are
preferably reaction products derived from the esterification of at
least one organic diol, at least one polycarboxylic acid and at
least one polyol. Such polymers typically form polyesters or
polyether polyols which are cross-polymers, i.e., they are
cross-linked polymer chains having a cross-link density of about
0.1 to about 2.0. The cross-linking may be controlled by adjusting
the amount of polyol in the monomer charge to the reaction.
[0067] Suitable organic diols are one or more such diols which may
be branched and/or linear, saturated and/or unsaturated, aliphatic
and/or aromatic and are about two to about fifty four carbon atoms
in length with two hydroxyl groups, including, for example,
ethylene glycol, 2,2,4-trimethyl-1-3 pentane diol, 1,2-propanediol;
1,3-propanediol; 1,3-butylene glycol; 1,4-butanediol;
2-methyl-1,3-propanediol; diethylene glycol; tetraethylene glycol;
1,5-pentanediol; neopentyl glycol; 1,6-hexanediol; dipropylene
glycol; 1,2-octanediol; dimerdiol, and combinations of the above
components. Preferred compounds are pentane diols and alkyl pentane
diols.
[0068] The at least one polycarboxylic acid may be an acid or in
its anhydride form, but is preferably an acid for random
polymerization. Further, while polyacids having more than two
carboxylic acid groups (or their anhydride forms) may be used, a
diacid is preferred. Suitable polyacids may be branched and/or
linear, saturated and/or unsaturated, aliphatic and/or aromatic and
may have from about two to about fifty four carbon atoms, and two
to four, but more preferably two, carboxylic acid and/or anhydride
groups, specifically preferred are diacids. Such acids may also
have from zero to two sulfonic acid groups (and acid salts
thereof). Examples of preferred polyacids are without limitation,
carbonic acid; propanedioic acid; decanedioic acid; pentanedioic
acid; hexanedioic acid (adipic acid); heptanedioic acid;
octanedioic acid; nonanedioic acid; decanedioic acid; dimer acid;
trimer acid; tetramer acid; phthalic acid; isophthalic acid;
pyromellitic acid; naphthylene dicarboxylic acid; sodium
sulfophthalic acid and combinations thereof.
[0069] The above-noted polyacids and/or organic diols may omit any
UV-absorbing moiety or may contain an UV-absorbing entity as
described in U.S. Publication No. 2011/0104078 A1.
[0070] The polyols are preferably those which have three or more
hydroxyl groups to provide a site of cross-linking as well as
reactive functionality. Suitable polyols include but are not
limited to dimerdiol, trimethylolpropane, ditrimethylolpropane,
glycerol, 1,2,3-propane triol, and combinations thereof.
Preferably, the polyol is glycerol.
[0071] The random polymer is preferably combined in a manner that
the ratio of diol:polycarboxylic acid:polyol is about 5:5:1 to
about 25:25:1, and most preferably about 10:10:1. The polymer is
preferably formed by thermal esterification at from about
100.degree. C. to about 250.degree. C. and a pressure of about 760
mmHg to about 1 mm Hg.
[0072] Other components may be provided to the composition
including those known in the art of sunscreen formulations, or for
use in personal care compositions such as cosmetics the require a
sunscreen. Particularly preferred are emollients, such as esters.
The compositions may include, optionally, for example, surfactants,
buffers, perfumes, colorants, dyes, viscosity modifiers, water,
oils, emulsifiers, preservatives, antioxidants, emollients,
thickeners, gellants, vitamins, humectants, alcohols, botanical
extracts and powders. Other suitable additive or components include
may include one or more vegetable oils in the product, such as, for
example, almond oil, castor oil, coconut oil, corn (maize) oil,
cottonseed oil, canola oil, flax seed oil, hempseed oil, nut oil,
olive oil, palm oil, peanut oil, safflower oil, sesame oil, soybean
oil, sunflower oil, jojoba oil and combinations of these oils.
[0073] Surfactants may be included in the personal care
composition, such as, for example, an anionic surfactant, a
zwitterionic surfactant, a cationic surfactant, a non-ionic
surfactant and combinations of these. Other exemplary components or
additives may include, without limitation, lipids, additional
alcohols, waxes, pigments, vitamins, fragrances, bleaching agents,
antibacterial agents, anti-inflammatory agents, antimycotic agents,
thickeners, gums, starches, chitosan, polymeric materials,
cellulosic materials, glycerin, proteins, amino acids, keratin
fibers, fatty acids, siloxanes, botanical extracts, abrasives
and/or exfoliants (chemical or mechanical), anticaking agents,
antioxidant agents, binders, biological additives, buffering
agents, bulking agents, chelating agents, chemical additives,
denaturants, external analgesics, film formers, humectants,
opacifying agents, pH adjusters, preservatives, propellants,
reducing agents, sunscreen agents, skin darkening agents, essential
oils, skin sensates, and combinations of these.
[0074] The personal care composition of the invention may also
include one or more optical brighteners as described in U.S. Patent
Publication No. 2011/0104078 A1, incorporated in relevant part
herein by reference, and also including for example, a
triazine-stilbenes (di-, tetra- or hexa-sulfonated), a courmarin,
an imidazoline, a diazole, a triazole, a benzoxazoline, and a
biphenyl stilbene.
[0075] Also included within the scope of the invention is a method
of protecting skin, hair, and/or nails of a mammal from damage
caused by exposure to light in the UV wavelengths by applying to
the skin, hair or nails a composition as described above, and that
is particularly useful when the skin, hair or nails is damp, moist
or otherwise wet. "Skin" includes the external integument of living
mammals, reptiles, amphibians, birds and other animals as well as
processed skins, such as leathers or suedes. "Hair" includes hair,
fur, wool and other filamentous keratinized structures of mammals
and other animals. Similarly, "nails" includes claws, hooves and
analogous structures of mammals and other animals.
[0076] Also within the scope of the invention are methods to
improve the aesthetics of photoprotective formulations by using the
composition so as to avoid a feeling of oiliness and/or greasiness
without substantial loss or separation of ingredients when skin is
damp, moist or otherwise wet.
[0077] The invention will now be described with respect to the
following non-limiting examples:
EXAMPLE 1
[0078] In this example, Phase A ingredients, identified in Table 1
below, were heated to 40.degree. C. or until the solids were
dissolved, and mixed until uniform.
[0079] The Phase B ingredients from Table 1 were mixed until
uniform.
[0080] The uniform Phase B ingredients were added to the Phase A
ingredients after the Phase A Ingredient mixture had cooled to room
temperature and all ingredients were mixed well to form sunscreen
formulations
[0081] As a screening tool, the applicant herein developed a simple
water dispersibility test. In the test, 0.1 gram of a sunscreen
formulation was dropped into 100 grams of deionized water in a 200
milliliter beaker. This simulates the extreme dilution that occurs
when fine atomized droplets of sunscreen lay upon large water
droplets on the skin. FIG. 3 shows a comparison of the Control
formulation versus the Example formulation containing a polymer
according to the invention herein. The photos in FIG. 3 show
clearly how the addition of only the inventive polymer to the
Example formulation dramatically improved the water tolerance and
dispersibility of the oil phase components in dilute solution in
water, which is the key to non-whitening efficacy prior to rubbing
in of the product.
TABLE-US-00001 TABLE 1 SPF 30 SPF 30+ Ingredients Trade Name
Control Example Phase A Neopentylglycol Lex Solv .TM. A .sup.1 4.00
4.00 Diheptanoate (and) Propylene Glycol Dibenzoate
Trimethylpentanediol/Adipic Example Polymer -- 2.00 Acid/Glycerin
Crosspolymer Octocrylene NeoHeliopan 303 .sup.2 2.75 2.75
Oxybenzone NeoHeliopan BB .sup.2 6.00 6.00 Octisalate NeoHeliopan
303 5.00 5.00 Homosalate NeoHeliopan HMS 10.00 10.00 Avobenzone
NeoHeliopan 357 .sup.2 3.00 3.00 Octinoxate NeoHeliopan AV .sup.2
7.50 7.50 Phase B Alcohol SDA 40B SD Alcohol 40B 57.25 55.25 C9-12
Isoalkanes Isopar H Fluid .sup.3 1.00 1.00 C13-14 Isoparaffin
Isopar M Solvent .sup.3 3.50 3.50 Total 100.00 100.00 .sup.1
Available from Inolex, Inc., Philadelphia, PA; .sup.2 Available
from Symrise AG, Teterboro, NJ; and .sup.3 Available from
ExxonMobil, Houston, TX. indicates data missing or illegible when
filed
[0082] To further illustrate the improvement conferred by the
inventive example formulation over the control, the SPF 30 Control
and SPF-30+ inventive Example formulations were sprayed onto wet,
600-grit, black sandpaper in an identical manner. While sandpaper
is not a substitute for human skin, the results clearly showed
similar behavior to that which was experienced in vivo, but was
much easier to see in photographic form.
[0083] FIG. 4 shows the Control formulation. It is clear by the
larger droplet size and whitening within the droplets that
coalescence and plating out of the oily components has occurred.
FIG. 5 illustrates how the addition of the inventive Example
polymer has reduced coalescence, and virtually eliminated any
whitening effect.
[0084] FIGS. 6 and 7 show the comparison of the two formulations on
human skin.
EXAMPLE 2
[0085] Using the formulations of Example 1, further evaluations
were undertaken to measure various parameters of the
formulations.
[0086] In-Vivo Whitening and Gloss After Drying:
[0087] Whitening:
[0088] The Minolta Chroma Meter CR-300 is a useful tool for the
objective assessment of surface color, and is often used in studies
to quantify skin color change. Typical applications where it has
been used is in the determination of the efficacy of
anti-irritants, tanning accelerators, and antiperspirants. It is a
reflectance colorimeter, and surface color data is output in the
form of the L* a* b* color coordinate system. The L* value relates
to skin lightness, while the a* (red/green) and b* (blue/yellow)
values are measures of skin color. Since the base color of
individual subjects varies, it is important to use a combination of
the L*, a* and b* coordinates to determine changes before and after
application of any product that is expected to change the color of
the skin. The value that represents the complete picture, .DELTA.E*
is a linear combination of the changes in both skin lightness as
well as color. .DELTA.E* is calculated using the following
equation:
.DELTA.E*= {square root over
((.DELTA.L*).sup.2+(.DELTA.a*).sup.2+(.DELTA.b*).sup.2)}
wherein .DELTA.L*, .DELTA.a*, and .DELTA.b* are differences between
values obtained before and after product application. The lower
change in .DELTA.E* change, the less the color of the skin is
altered.
[0089] Shine:
[0090] The gloss of the surface of skin can be expressed by direct
reflection of light sent to the surface. The Skin-Glossymeter
GL-200, from Khazaka of Koln is a probe which measures both the
portion of directly reflected light (Reflection channel, R) which
is related to the gloss, and the scattered portion from the surface
(Diffuse channel, D) as illustrated in the schematic representation
of FIG. 8 provided by Khazaka. The value obtained, the Skin Gloss
Value (SGV) is unitless, and is a function of probe design.
Additionally, the Skin-Glossymeter GL-200 is specially designed to
assess the gloss of the skin surface with diffuse scattering
correction (DSC), thus allowing the comparison of gloss
measurements obtained from different skin types accurately without
interference of skin color or formulation color.
[0091] Procedure
[0092] Volunteers were allowed acclimate with the environment by
waiting in a controlled setting of 22-24.degree. C., at 15-20%
relative humidity for 20 minutes. Areas of the volar forearm were
cleaned with isopropanol and wiped dry with a paper towel prior to
being marked with four centimeter diameter circles sufficient for
control and treatment application of the product. Control color
index values L*, a* and b* were then obtained. Test areas were then
sprayed with 0.3 grams of water, then evenly sprayed with 0.3 grams
of the sunscreen. Subjects were then held in the waiting area for
twenty minutes over which time the sunscreens completely dried.
Control color index values L*, a* and b* were again obtained.
[0093] In addition to the above, visual observations were made
using a rating system from 0-10 with a higher value relating to
higher whitening.
[0094] Lastly, skin gloss values were obtained using the
Glossymeter GL-200. The above information was obtained for the SPF
30+ inventive Example formulation to compare it with a current
leading commercial alcohol spray formulation designed for wet skin
including in its formulation in active part: 3% avobenzone, 8%
homosalate, 4% octisalate, 8% octocrylene, 5% oxybenzone and
various inactive ingredients (denatured alcohol, dimethyl ether,
octyldodecyl citrate crosspolymer, acrylates/octylacrylamide
copolymer, ethyl methicone, cetyl dimethicone, dimethicone,
acrylates/dimethicone copolymer, fragrance, tocopheryl acetate,
vinyl dimethicone crosspolymer, nelumbo nucifera flower powder,
diethylhexyl-2,6-naphthalate, ascorbyl palmitate and retinyl
palmitate). The results are shown graphically in FIG. 10.
EXAMPLE 3
[0095] In the Example, static SPF value and water resistance SPF
were obtained through clinical testing on the skin of panelists.
ISO Standard 24444, incorporated herein by reference, was used to
evaluate in-vivo SPF and water resistance on dry skin. A
modification of ISO 24444 in which static SPF and water resistance
was measured on wet skin was also employed. The modification
consisted of pre-spraying the skin with 2 mg/cm.sup.2 of water
immediately before applying the sunscreen. The formulation is shown
in Table 2 below as Formulation A.
TABLE-US-00002 TABLE 2 Ingredients (% wt/wt) Trade Name Formulation
A Neopentylglycol Diheptanoate (and LexSolv .TM..sup.1 5.00
Propylene Glycol Dibenzoate Trimethylpentanediol/Adipic Example 2
Polymer 2.00 Acid/Glycerin Crosspolymer Octocrylene NeoHeliopan
303.sup.2 10.00 Bis-Ethylhexyloxyphenol Tinosorb S.sup.3 3.00
Octisalate NeoHeliopan OS.sup.2 5.00 Diethylamino Hydyroxybenzoyl
Unival A+.sup.3 2.00 Hexyl Benzoate Ethylhexyl Triazone Unival
T-150.sup.3 3.00 Homosalate NeoHeliopan HMS.sup.2 10.00 Avobenzone
NeoHeliopan 357.sup.2 3.00 Alcohol SDA 40B -- 52.50 Isododecane
Permethyl 99A.sup.4 4.50 Total 100.00 .sup.1Inolex, Inc.
.sup.2Symrise .sup.3BASF .sup.4Presperse
[0096] The results are shown below in Table 3, wherein static SPF
and Water Resistance values represent an average of the three
subject data:
TABLE-US-00003 TABLE 3 Water Water Resistance SPF Resistance SPF
Sunscreen Static SPF (80 min., Static SPF (40 min., Formulation
(Dry Skin) Dry Skin) (Wet Skin) Wet Skin) A 56 52 56 52
[0097] The data support that the formulation has equivalent SPF
when applied to both dry and wet skin, and is water resistant when
applied to both dry and wet skin.
[0098] It will be appreciated by those skilled in the art that
changes could be made to the embodiments described above without
departing from the broad inventive concept thereof. It is
understood, therefore, that this invention is not limited to the
particular embodiments disclosed, but it is intended to cover
modifications within the spirit and scope of the present invention
as defined by the appended claims.
* * * * *