1. Field of the Invention
The present invention relates to a method for lengthening keratin fibers of the scalp, eyebrows or eyelashes.
2. Description of the Related Art
Mascara compositions are commonly employed by women to highlight and enhance the appearance of eyelashes. Such enhancements may include the impartation of color or tone, volume, i.e., thickness and length, and curl. Volume and length have been enhanced by the inclusion of fibers in the mascara compositions. For instance, U.S. Pat. No. 6,726,917 discloses a volumizing and lengthening mascara composition having fibers, pigments, and a water-soluble and an oil-soluble film formers. U.S. Pat. No. 6,656,487 discloses a composition having fibers and a copolymer having carboxylate groups and polydimethylsiloxane groups. However, since the size of fibers that can be incorporated into a mascara composition has practical limits, the benefit to be obtained by incorporating fibers is also limited.
One means employed in the art to lengthen eyelashes to a considerable degree is to apply false eyelashes, which are applied by attaching fibers to the base of the eyelashes with an adhesive. Use of false eyelashes can be cumbersome and/or require professional application.
Another means employed in the art to lengthen eyelashes is to build length through multiple applications of a single composition or multiple sequential applications of two or more different compositions.
In the first technique, a formulation of one composition (hereinafter referred to as “single composition”) is applied as a single layer and left to set or dry. Then a second layer of the single composition is applied over the single layer. The second layer adds incremental length beyond that of the first layer. Application of the single composition can be repeated as many times as needed to yield the desired eyelash length. Single compositions are commonly wax-based or polymer-based. PCT Application No. 95/15741 discloses a mixture of waxes to impart properties such as film hardness and adhesion to the eyelash. U.S. Provisional Patent Application No. 20020168335A1 discloses a cosmetic composition having a wax and a polymer.
In the second technique, two different compositions are applied sequentially. In such sequenced systems, the first composition, which is typically clear or white in color, is applied to the eyelash to impart a degree of lengthening and is allowed to set or dry. Once the first composition has set, the second composition, which is typically of a color such as black, brown, or blue, is applied over the primary composition imparting additional length. In European Patent Application 1516612A2, a washable mascara is applied to the eyelashes and followed with application of a waterproof mascara. U.S. Provisional Patent Application No. 20050061349A1 discloses a sequenced system employing a composition having fibers in either a washable or waterproof mascara. Using the aforementioned multiple-application techniques for lengthening eyelashes is time-consuming since the changes in length are incremental and gradual.
It would be desirable to have a method for lengthening keratin fibers, such as those of the scalp, eyebrows, and eyelashes, to a considerable degree. It would be further desirable for such lengthened keratin fibers to last for an extended period of time. A consumer need exists for a fast and effective way to lengthen eyelashes without using false eyelashes or products that rely on multiple-application techniques.