United States Patent:  6,074,630

Appl. No.:  447802

A delivery system for sunscreen products that applies a dry, waterproof sunscreen composition to the skin. The delivery system for suncare products of the present invention is designed to apply only the required amount of sunscreen composition to the skin without excess. The sunscreen composition is applied to an article such as paper, nonwoven cloth or porous plastic which is subsequently rubbed onto the skin. Alternatively, the sunscreen may take the form of a wafer or a bar with or without a support article. A delivery system for suncare products which include dihydroxyacetone in order to produce a semi-permanent color that gives the appearance of a natural suntan is described which utilizes the same self-leveling principle as the delivery system for suncare products containing sunscreen compositions.

SUMMARY OF THE INVENTION

Accordingly, it is a principal object of the invention to provide a safe and effective dry sunscreen composition and a delivery system for the sunscreen composition. The sunscreen composition contains at least a waterproofing agent and a sunscreen agent. The sunscreen composition utilized in this invention is not messy and since it is applied in a dry state it covers the desired area of the skin evenly without any areas containing an excessive amount of the active ingredients in the sunscreen composition. The application substrate controls the amount of sunscreen per square centimeter that can be delivered onto the skin. Additional applications will not apply heavier levels of sunscreen to the skin because the amount of the product applied to the skin is controlled by the relative affinity of the product to the skin and to its applicator; this phenomenon is referred to hereinafter as self-leveling.

Self-leveling is also apparent in the application of

dihydroxyacetone. The dihydroxyacetone sunless tanning composition is in an aqueous solution and may contain a sufficient amount of emulsifier to produce an effective emulsion. The resultant dihydroxyacetone sunless tanning composition is self-leveling. The composition is disposed on a porous or fibrous substrate serving as an applicator which is applied to the skin by wiping the applicator on the skin. The amount of the product applied to the skin is controlled by the opposing capillary attractive forces of the dihydroxyacetone composition for the applicator and its affinity for the skin.

It is another object of the invention to provide a sunscreen composition, and a delivery system for the sunscreen composition, which has greater SPF values with the same application density. The sunscreen composition of the present invention has a means for application, the delivery system for suncare products, wherein the applicator is labeled to treat a certain amount of skin so that sufficient sunscreen will be available to adequately and completely coat the skin with a controlled concentration of sunscreen. The method of application controls the amount of active sunscreen agents that is applied per square centimeter.

It is a further object of the invention to have a sunscreen delivery system which applies a sunscreen composition that has superior waterproofing properties which is also effective upon application.

It is an object of the invention to provide a system that applies dihydroxyacetone evenly without blotchiness or streaking in the color that develops.

Still another object of the invention is to minimize adverse and allergic reactions due to the addition of unnecessary emulsifiers and other excessive ingredients found in many sunscreen compositions.

It is an object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.

Claim 1 of 25 Claims

1. A method of delivering a sunscreen product, comprising the steps of:

a) selecting a sunscreen agent;

b) adding at least a waterproofing agent to said sunscreen agent in order to formulate an anhydrous, nonemulsified sunscreen composition having a high concentration of sunscreen agent;

c) determining a maximum allowable concentration of said sunscreen agent as a weight to weight percentage;

d) determining the percentage of said sunscreen agent in said sunscreen composition by percentage weight of sunscreen agent to total weight of the composition;

e) determining an equivalent application rate by multiplying said maximum allowable concentration by 2 mg/cm² and dividing by the percentage of sunscreen agent in said sunscreen composition;

f) selecting a matrix for delivering said sunscreen composition to the skin of a user at said equivalent application rate; and

g) disposing said sunscreen composition in and on said matrix.

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