# Patent

## Title
Implementing organic materials in sunscreen applications

## Abstract

Techniques for implementing organic materials in sunscreen applications are provided herein. A method includes selecting a combination of multiple organic materials to incorporate into a sunscreen composition, wherein said selecting is based on (i) a desired absorption spectrum of the sunscreen composition, (ii) the absorption spectrum of each of the multiple organic materials, and (iii) a particle size limitation for each of the multiple organic materials, and incorporating the selected combination of organic materials into the sunscreen composition to generate the desired absorption spectrum. A composition includes a combination of multiple organic materials incorporated into a sunscreen composition, wherein the combination of organic materials is selected based on (i) a desired absorption spectrum of the sunscreen composition, (ii) the absorption spectrum of each of the multiple organic materials, and (iii) a particle size limitation for each of the multiple organic materials.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority to U.S. Provisional Application Ser. No. 62/213,715, filed Sep. 3, 2015, incorporated by reference herein.


FIELD
The present application generally relates to chemical technology, and, more particularly, to sunscreen technologies.
BACKGROUND
Sunscreen creams and other such compositions are commonly used to prevent ultraviolet (UV) radiation (also referred to herein as “light” in this context) from reaching the skin of a human user and causing damage. It is noted that UV light is an electromagnetic radiation with a wavelength range between approximately 280 nanometers (nm) and approximately 400 nanometers (specifically, that is the range of UV radiation that is not absorbed by the ozone).
A common active ingredient of existing sunscreen compositions is zinc oxide (ZnO). ZnO is a semiconductor that has a specific band gap, and particles of ZnO used in existing sunscreen compositions are typically approximately 50-200 nm in size. Additionally, in existing sunscreen compositions, typical ZnO materials are capable of absorbing UV light (that is, blocking the UV light from passing through the sunscreen composition to be absorbed by the skin of the user) within a wavelength range of approximately 290 nm through only approximately 350-380 nm.
Further, it is noted that some amount of high-energy light (for example, light within a wavelength range of approximately 270 nm to approximately 300 nm) is needed by the human body for producing vitamin D (which is useful, for example, in calcium absorption and bone growth). Accordingly, while existing sunscreen compositions are capable of blocking portions of UV light from passing through the composition to be absorbed by the skin of the user, such compositions simultaneously preclude the UV light responsible for aiding vitamin D production to be absorbed by the skin.
SUMMARY
In one embodiment of the present invention, techniques for implementing organic materials in sunscreen applications are provided. An exemplary method can include steps of selecting a combination of multiple organic materials to incorporate into a sunscreen composition, wherein said selecting is based on (i) a desired absorption spectrum of the sunscreen composition, (ii) the absorption spectrum of each of the multiple organic materials, and (iii) a particle size limitation for each of the multiple organic materials, and incorporating the selected combination of organic materials into the sunscreen composition to generate the desired absorption spectrum.
In another embodiment of the invention, a composition can include a combination of multiple organic materials incorporated into a sunscreen composition, wherein the combination of organic materials is selected based on (i) a desired absorption spectrum of the sunscreen composition, (ii) the absorption spectrum of each of the multiple organic materials, and (iii) a particle size limitation for each of the multiple organic materials.
These and other objects, features and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph illustrating absorption coefficients of four organic materials, according to an embodiment of the invention;
FIG. 2 is a graph illustrating absorption coefficients of three organic materials, according to an embodiment of the invention;
FIG. 3A and FIG. 3B are graphs illustrating absorption and emission coefficients of one or more organic materials, according to an embodiment of the invention; and
FIG. 4 is a flow diagram illustrating techniques, according to an embodiment of the invention.



DETAILED DESCRIPTION
As described herein, an embodiment of the present invention includes zinc oxide compositions, methods of fabrications thereof and methods of use thereof. Specifically, at least one embodiment of the invention includes techniques for implementing organic materials in sunscreen applications.
As further detailed herein, one or more embodiments of the invention include generating ZnO compositions and methods of use thereof for effectively blocking more and/or all of the complete spectrum of UV light (that is, as noted above, the UV radiation that is not absorbed by the ozone, and which ranges between approximately 280 nm and 400 nm). Additionally, one or more embodiments of the invention include generating ZnO compositions and methods of use thereof for permitting a specific range (or “windows”) of light (radiation) to pass through a ZnO composition such that the specific range of light can be absorbed by the skin of a human user. For example, at least one embodiment of the invention can include generating a ZnO composition that allows radiation at 276 nm (which is the wavelength that facilitates vitamin D absorption in the skin) to pass through the composition to be absorbed by the skin, while blocking harmful UV radiation at other wavelengths.
At least one embodiment of the invention can include combining multiple organic materials with to create a sunscreen composition with a specific absorption spectrum. The absorption coefficient is typically much higher in organic material than in inorganic materials. Accordingly, in one or more embodiments of the invention, less of the organic materials would be necessary (than, for example, relevant inorganic materials) to achieve the same objective(s). For example, a combination of multiple organic materials, each having a specific absorption spectrum, can cover (that is, absorb) the entire UV spectrum. In one or more embodiments of the invention, example organic materials can include, but are not limited to, (i) fin(II) phthalocyanine (SnPc), (ii) chloroaluminum phthalocyanine (ClAlPc), (iii) squaraine (SQ), (iv) N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2′-dimethylbenzidine (a-NPD), (v) N,N′-Bis(3-methylphenyl)-N,N′-bis(phenyl)-benzidine (TPD), (vi) 4,4′,4′′-Tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine (MTDATA), etc.
Additionally, one or more embodiments of the invention can include implementing organic materials by themselves (that is, without any inorganic particles) to create a sunscreen composition. Alternatively, at least one embodiment of the invention can include implementing one or more organic materials as a coating applied to inorganic particles, such as ZnO, to create a sunscreen composition. Accordingly, by way of example, a combination of organic materials can be used to replace ZnO particles in a sunscreen composition and/or to supplement ZnO particles in a sunscreen composition.
FIG. 1 is a graph 100 illustrating absorption coefficients of four organic materials, according to an embodiment of the invention. Based on the illustrated absorption coefficients of the four noted organic materials, the combination of these four materials can, for example, replace ZnO in a sunscreen composition, as this combination of organic materials covers and/or replicates the absorption spectrum of ZnO with respect to UV light.
FIG. 2 is a graph 200 illustrating absorption coefficients of three organic materials, according to an embodiment of the invention. Specifically, the combination of organic materials illustrated in FIG. 2 is similar to the combination illustrated in FIG. 1, except that the organic material that absorbs light within the approximate wavelength of 276 nm has been removed from the combination. Consequently, such a combination can cover and/or replicate the absorption spectrum of ZnO with respect to UV light, while also permitting light to pass through (that is, not be absorbed) at a wavelength that will facilitate vitamin D production in the skin.
FIG. 3A and FIG. 3B are graphs (301 and 302, respectively) illustrating absorption and emission coefficients of one or more organic materials, according to an embodiment of the invention. It is to be appreciated that light absorbed by an organic material (such as those depicted in FIG. 3A and FIG. 3B) is emitted by that organic material at a higher wavelength (than is absorbed).
In at least one embodiment of the invention, organic fluorescent material (that is, light that is emitted after being absorbed) can be used to enhance vitamin D wavelength (at 276 nm, for instance) light intensity. It is noted that the wavelength of a fluorescent organic material is typically approximately 20 nm longer than the corresponding absorption wavelength. Accordingly, compositions can be designed using materials that emit at desired wavelengths to accentuate and/or emphasize certain optical effects or characteristics. As depicted, for example, in FIG. 3B, emission from material 2, which includes light at 276 nm, can be utilized in conjunction with a lack of material which absorbs light at 276 nm to create a sunscreen composition that emphasizes the passing of light at 276 nm so as to facilitate vitamin D production in the skin of the user.
FIG. 4 is a flow diagram illustrating techniques according to an embodiment of the present invention. Step 402 includes selecting a combination of multiple organic materials to incorporate into a sunscreen composition, wherein said selecting is based on (i) a desired absorption spectrum of the sunscreen composition, (ii) the absorption spectrum of each of the multiple organic materials, and (iii) a particle size limitation for each of the multiple organic materials. In one or more embodiments of the invention, the desired absorption spectrum of the sunscreen composition can include the spectrum of ultraviolet light. In such an embodiment, each of the multiple organic materials can have an absorption spectrum that covers a portion of the spectrum of ultraviolet light. Additionally, in at least one embodiment of the invention, the desired absorption spectrum of the sunscreen composition can include the spectrum of ultraviolet light outside of the portion of the spectrum of ultraviolet light responsible for facilitating vitamin D production.
The selecting step can further be based on the color that each of the multiple organic materials affect upon the sunscreen composition. In one or more related embodiments of the invention, depending upon the color affected upon the sunscreen composition, such a composition can serve the function as a makeup. Also, in one or more embodiments of the invention, the selecting step can be further based on the emission spectrum of each of the multiple organic materials. In such an embodiment, the desired absorption spectrum of the sunscreen composition can include the spectrum of ultraviolet light outside of the portion of the spectrum of ultraviolet light responsible for facilitating vitamin D production, and at least one of the multiple organic materials can have an emission spectrum that covers the portion of the spectrum of ultraviolet light responsible for facilitating vitamin D production.
In one or more embodiments of the invention, the organic materials can include (i) fin(II) phthalocyanine, (ii) chloroaluminum phthalocyanine, (iii) squaraine, (iv) N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2′-dimethylbenzidine, (v) N,N′-Bis(3-methylphenyl)-N,N′-bis(phenyl)-benzidine, and/or (vi) 4,4′,4′′-Tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine.
Additionally, in one or more embodiments of the invention, the particle size limitation comprises a limitation of less than two hundred nanometers to reduce Rayleigh scattering and reduce whitening of the sunscreen composition. Also, such an embodiment can further include embedding the organic materials in a particle of a size that is greater than two hundred nanometers, such that optical spacing is maintained between the organic materials (to reduce scattering). Alternatively, such an embodiment can additionally include attaching the organic materials to a particle of a size that is greater than two hundred nanometers, such that optical spacing is maintained between the organic materials (to reduce scattering).
Step 404 includes incorporating the selected combination of organic materials into the sunscreen composition to generate the desired absorption spectrum. Additionally, the techniques depicted in FIG. 4 can also include applying the selected combination of organic materials as a coating to the surface of each of one or more zinc oxide particles within the sunscreen composition.
Also, an additional embodiment of the invention includes a composition that includes a combination of multiple organic materials incorporated into a sunscreen composition, wherein the combination of organic materials is selected based on (i) a desired absorption spectrum of the sunscreen composition, (ii) the absorption spectrum of each of the multiple organic materials, and (iii) a particle size limitation for each of the multiple organic materials. In such a composition, the combination of organic materials can optionally be applied as a coating to the surface of each of one or more zinc oxide particles within the sunscreen composition.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of another feature, step, operation, element, component, and/or group thereof.
At least one embodiment of the present invention may provide a beneficial effect such as, for example, implementing a combination of multiple organic materials to create a composition that can absorb the entire UV spectrum.
The descriptions of the various embodiments of the present invention have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

## Claims

1. A composition comprising:
a combination of organic materials incorporated into a sunscreen composition, wherein the sunscreen composition comprises one or more zinc oxide particles, wherein the combination of organic materials is selected based on:
(i) a desired absorption spectrum of the sunscreen composition, wherein the desired spectrum comprises the spectrum of ultraviolet light outside of the portion of the spectrum of ultraviolet light responsible for facilitating vitamin D production, and
(ii) the absorption spectrum of each of the organic materials; and
wherein the combination of organic materials comprises at least two of (a) chloroaluminum phthalocyanine, (b) squaraine, (c) N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2′-dimethylbenzidine, (d) N,N′-Bis(3-methylphenyl)-N,N′-bis(phenyl)-benzidine, and (e) 4,4′,4′′-Tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine.

2. The composition of claim 1, wherein the particle size of each of the organic materials is less than two hundred nanometers.

3. The composition of claim 2, wherein each of the organic materials are (i) embedded in the one or more zinc oxide particles such that optical spacing is maintained between the embedded organic materials, and/or (ii) attached to the one or more zinc oxide particles such that optical spacing is maintained between the attached organic materials, and wherein the particle size of the one or more zinc oxide particles is greater than two hundred nanometers.

4. The composition of claim 1, wherein the combination of organic materials further comprises tin(II) phthalocyanine.

5. The composition of claim 1, wherein the combination of organic materials comprises a coating to the surface of each of the one or more zinc oxide particles within the sunscreen composition.

6. The composition of claim 1, wherein the combination of organic materials is selected further based on the emission spectrum of each of the organic materials.

7. The composition of claim 6, wherein at least one of the organic materials has an emission spectrum that covers the portion of the spectrum of ultraviolet light responsible for facilitating vitamin D production.

8. A composition comprising:
a combination of organic materials incorporated into a sunscreen composition, wherein the sunscreen composition comprises one or more zinc oxide particles, wherein the combination of organic materials is selected based on:
(i) a desired absorption spectrum of the sunscreen composition, wherein the desired spectrum comprises the spectrum of ultraviolet light outside of the portion of the spectrum of ultraviolet light responsible for facilitating vitamin D production, and
(ii) the absorption spectrum of each of the organic materials; and
wherein the combination of organic materials comprises at least two of (a) chloroaluminum phthalocyanine, (b) squaraine, (c) N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2′-dimethylbenzidine, (d) N,N′-Bis(3-methylphenyl)-N,N′-bis(phenyl)-benzidine, (e) 4,4′,4′′-Tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine, and (f) tin(II) phthalocyanine.

9. The composition of claim 8, wherein the combination of organic materials comprises a coating to the surface of each of the one or more zinc oxide particles within the sunscreen composition.

10. The composition of claim 8, wherein the combination of organic materials is selected further based on the emission spectrum of each of the organic materials.

11. A composition comprising:
a combination of organic materials incorporated into a sunscreen composition, wherein the sunscreen composition comprises one or more zinc oxide particles, wherein the combination of organic materials is selected based on:
(i) a desired absorption spectrum of the sunscreen composition, wherein the desired spectrum comprises the spectrum of ultraviolet light outside of the portion of the spectrum of ultraviolet light responsible for facilitating vitamin D production, and
(ii) the absorption spectrum of each of the organic materials; and
wherein the combination of organic materials comprises (a) chloroaluminum phthalocyanine, (b) squaraine, (c) N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2′-dimethylbenzidine, (d) N,N′-Bis(3-methylphenyl)-N,N′-bis(phenyl)-benzidine, (e) 4,4′,4′′-Tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine, and (f) tin(II) phthalocyanine.

12. The composition of claim 11, wherein the combination of organic materials comprises a coating to the surface of each of the one or more zinc oxide particles within the sunscreen composition.

13. The composition of claim 11, wherein the combination of organic materials is selected further based on the emission spectrum of each of the organic materials.