Drug – bio-affecting and body treating compositions – Topical sun or radiation screening – or tanning preparations – Aromatic acid or derivative containing
Reexamination Certificate
2002-11-22
2004-10-05
Killos, Paul J. (Department: 1625)
Drug, bio-affecting and body treating compositions
Topical sun or radiation screening, or tanning preparations
Aromatic acid or derivative containing
C424S059000, C558S400000, C560S081000
Reexamination Certificate
active
06800274
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to compounds and methods to increase the photostability of a sunscreen composition. Moreover, the invention relates to photostable sunscreen compositions and a new class of photoactive compounds. More particularly, the invention relates to the use of derivatives of diphenylmethylenemalonic acid and derivatives of fluorene, including derivatives of cyano(9H-fluoren-9-ylidene) acetic acid and diesters and polyesters of 9H-fluoren-9-ylidenemalonic acid to photostabilize a sunscreen composition.
2. Brief Description of Related Technology
It is well known that ultraviolet radiation (light) having a wavelength from about 280 nm or 290 nm to about 320 nm (UV-B) is harmful to human skin, causing burns that are detrimental to the development of a good sun tan. UV-A radiation (about 320 nm to about 400 nm), while producing tanning of the skin, also can cause damage, particularly to very lightly-colored or sensitive skin, leading to reduction of skin elasticity and wrinkles. Therefore, a sunscreen composition for use on human skin preferably includes both a UV-A and a UV-B filter to prevent most of the sunlight within the full range of about 280 nm or 290 nm to about 400 nm from damaging human skin.
Ultraviolet radiation from the sun or artificial sources can also cause harm to coatings containing photoactive substances, such as photoactive pigments and dyes, by breaking down chemical bonds in the structure of a component such as a polymer, a pigment, or a dye. This photodegradation can lead to color fading, loss of gloss, and loss of physical and protective properties of a coating. Photodegradation can take place in several steps which include one or more components of a coating absorbing UV radiation. The absorbed radiation can excite the absorbing molecules and raise them to a higher energy level, which can be very reactive. If the molecule cannot be relaxed, bond cleavage and the formation of free radicals will occur. These free radicals can attack one or more color molecules and/or a polymer backbone and form more free radicals. UV-A and UV-B filters can also be used to absorb UV radiation to protect a pigmented coating.
The UV-B filters that are most widely used in the U.S. in commercial sunscreen compositions are paramethoxycinnamic acid esters, such as 2-ethylhexyl paramethoxycinnamate, commonly referred to as octyl methoxycinnamate or PARSOL MCX, octyl salicylate, and oxybenzone.
The organic UV-A filters most commonly used in commercial sunscreen compositions are the dibenzoylmethane derivatives, particularly 4-(1,1-dimethylethyl)-4′-methoxydibenzoylmethane (also called avobenzone, sold under the brand name PARSOL 1789). Other dibenzoylmethane derivatives described as UV-A filters are disclosed in U.S. Pat. Nos. 4,489,057, 4,387,089 and 4,562,067, the disclosures of which are hereby incorporated herein by reference. It is also well known that the above described UV-A filters, particularly the dibenzoylmethane derivatives, can suffer from rapid photochemical degradation, when used alone or when combined with the above-described most commercially used UV-B filters.
Typically, the above-described UV-B filters are combined with the above described UV-A filters in a solution with other lipophilic or oily ingredients. This solution of oily ingredients, known to formulators of cosmetic products including sunscreens as the “oil phase,” is typically, but not necessarily, dispersed with the help of emulsifiers and stabilizers into an aqueous solution composed primarily of water, to make an emulsion which becomes a final cream or lotion form of a sunscreen composition.
The performance of a photoactive compound or a combination of photoactive compounds in a sunscreen composition has been extremely difficult to predict based on the levels of photoactive compounds in the formulation, particularly when the formulation includes one or more photoactive compounds that suffer from relatively rapid photodegradation, such as avobenzone. Because of this, each formulation has required expensive laboratory testing to determine the UV absorbance, as a function of time (quantity) of exposure of the formulation to UV radiation. Moreover, a particularly difficult problem is presented when one photoactive compound in a sunscreen composition acts to increase the rate of photodegradation of another photoactive compound in the composition. This can be accomplished in a number or ways, including a bimolecular reaction between two photoactive compounds and a lowering of the threshold energy need to raise a photoactive compound to its excited state. For example, when avobenzone is combined with octyl methoxycinnamate a bimolecular pathway leads to the rapid photodegradation of both the dibenzoylmethane derivative and the octyl methoxycinnamate.
Methods and compositions for stabilizing photoactive compounds, such as dibenzoylmethane derivatives with the use of diesters and/or a polyesters of naphthalene dicarboxylic acid are described in U.S. Pat. Nos. 5,993,789, and 6,284,916, the disclosures of which are hereby incorporated herein by reference. Other methods of stabilizing a dibenzoylmethane derivative include the addition of an &agr;-cyano-&bgr;,&bgr;-diphenylacrylate compound to a sunscreen composition including a dibenzoylmethane derivative. See, Deflandre et al, U.S. Pat. No. 5,576,354 and Gonzenbach et al., U.S. Pat. No. 6,033,649.
REFERENCES:
patent: 3215724 (1965-11-01), Strobel et al.
patent: 3215725 (1965-11-01), Strobel et al.
patent: 3272855 (1966-09-01), Strobel et al.
patent: 3275520 (1966-09-01), Strobel et al.
patent: 3337357 (1967-08-01), Strobel et al.
patent: 3445545 (1969-05-01), Skoultchi
patent: 3992356 (1976-11-01), Jacquet et al.
patent: 4107290 (1978-08-01), Jacquet et al.
patent: 4128536 (1978-12-01), Brodsky et al.
patent: 4178303 (1979-12-01), Lorenz et al.
patent: 4202834 (1980-05-01), Gruber et al.
patent: 4202836 (1980-05-01), Gruber et al.
patent: 4207253 (1980-06-01), Lorenz et al.
patent: 4218392 (1980-08-01), Lorenz et al.
patent: 4260719 (1981-04-01), Ching
patent: 4263366 (1981-04-01), Lorenz et al.
patent: 4276136 (1981-06-01), Gruber et al.
patent: 4387089 (1983-06-01), De Polo
patent: 4489057 (1984-12-01), Welters et al.
patent: 4562067 (1985-12-01), Hopp et al.
patent: 5013777 (1991-05-01), MacLeay et al.
patent: 5210275 (1993-05-01), Sabatelli
patent: 5576354 (1996-11-01), Deflandre et al.
patent: 5882633 (1999-03-01), Pisson et al.
patent: 5972324 (1999-10-01), Zofchak et al.
patent: 5993789 (1999-11-01), Bonda et al.
patent: 6033649 (2000-03-01), Gonzenbach et al.
patent: 6284916 (2001-09-01), Bonda et al.
patent: 6485713 (2002-11-01), Bonda et al.
patent: 6491901 (2002-12-01), Gers-Barlag et al.
patent: 2001/0022966 (2001-09-01), Gers-Barlag et al.
patent: WO 00/44340 (2000-08-01), None
“Photostability of HallStar Photostable SPF 32 Sunscreen Compared to Neutrogena UVA/UVB Sunblock SPF 30,” Suncare Research Laboratories, Memphis, Tennessee (Oct. 5, 2000).
Beckwith, in “The chemistry of amides: Synthesis of amides,” Zabicky, J., Ed. Interscience: New York, pp. 73-185 (1970).
Bentley et al., “Medium Effects on the Rates and Mechanisms of Solvolytic Reactions,”Adv. Phys. Org. Chem., vol. 14, pp. 1-67 (1977).
Bentley et al., “Y&khgr;Scales of Solvent Ionizing Power,”Progr. Phys. Org. Chem., vol. 17, pp. 121-158 (1990).
Dimroth et al.,Justus Liebigs Ann. Chem., vol. 661 pp. 1-37 (1963).
Fainberg et al., “Correlation of Solvolysis Rates. III. t-Butyl Chloride in a Wide Range of Solvent Mixtures,”J. Am Chem. Soc., vol. 78 pp. 2770-2777 (1956).
Grunwald et al., “The Correlation of Solvolysis Rates,” J. Am. Chem. Soc., vol. 70, pp. 846-854 (1948).
Haslem, “Recent Developments in Methods For the Esterification and Protection of the Carboxyl Group,”Tetrahedron, vol. 36, pp. 2409-2433 (1980).
Kamlet et al., “An Examination of Linear Solvation Energy Relationships,”Progr. Phys. Org. Chem., vol. 13, pp. 485-630 (1981).
Kosower, “The Effect of Solvent on Spectra. I. A New Empirical Measure of Solvent
Bonda Craig A.
Pavlovic Anna B.
Shah Urvil B.
Killos Paul J.
Marshall & Gerstein & Borun LLP
The C.P. Hall Company
LandOfFree
Photostabilizers, UV absorbers, and methods of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Photostabilizers, UV absorbers, and methods of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photostabilizers, UV absorbers, and methods of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3263474