Compositions for efficient release of active ingredients

Details Compositions for efficient release of active ingredients Compositions for efficient release of active ingredients

1999-12-17

2004-04-06

Page, Thurman K. (Department: 1615)

Drug, bio-affecting and body treating compositions

Preparations characterized by special physical form

Wearing apparel, fabric, or cloth

C424S400000, C424S443000, C424S444000, C424S447000, C424S449000, C424S445000, C424S446000, C424S070110, C604S385080, C604S368000, C604S378000, C514S946000, C514S947000

Reexamination Certificate

active

06716441

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention relates to the effective delivery of a therapeutic skin care active to the skin via a novel release composition which is preferably incorporated into a dispensing means. Many types of disposable absorbent articles, such as diapers, training pants, adult incontinence devices, sanitary napkins, panty liners, and the like are available to absorb and contain urine and other bodily exudates. Disposal products of this type generally comprise some sort of liquid-pervious topsheet material, an absorbent core, and a liquid-impervious backsheet material. While these absorbent articles are efficient for the absorption of liquids, they also create a more hostile environment than that is usually encountered by the skin, increasing the risk of skin irritations and/or diaper dermatitis. Diaper dermatitis or diaper rash is a condition where the stratum corneum is attacked and the skin is irritated and inflamed. The commonly known factors linked to diaper dermatitis include ammonia, bacteria, the products of bacterial actions, enzymes, pH, candida albicans and moisture. The diaper dermatitis is principally initiated by prolonged and repeated exposure to urine and feces under occlusive condition such as the micro-environment created by wearing an absorbent article. Under such condition, the skin may get overhydrated, leading to diminished barrier function. The friction and rubbing with the absorbent article create further damages to the skin. Thus, the skin becomes more susceptible to the irritants such as those in the urine or feces. While this condition is certainly more common in infants, it is not limited to infants. Similar conditions occur in, for example, incontinent or bed-ridden adults. Furthermore, similar skin irritation may occur from use of sanitary napkins and from repeated wiping/chaffing of sensitive skin.
Since there are multiple factors linked to diaper dermatitis, the practical approach attempts to address the multiple causes and/or important cofactors. For example, reducing skin hydration by frequent changing of diapers, the use of moisture absorbing powders, the use of superabsorbent materials, and improving air flow in diapers are well known approaches. The use of artificial barriers (e.g., ointments, lotions) is also widely practiced.
Typically, a topical cream, ointment, lotion or paste is applied to the skin under the absorbent article by hand to provide some degree of physical barrier protection against bodily exudates or irritants. For the topical application method to be effective, the creams or ointments need to be substantive, i.e., they need to coat the target surface and remain at the site of application. Most current topical delivery systems are O/W or W/O (oil in water or water in oil) emulsions. These emulsions generally have inferior substantive properties, hence they are easily removed by moisture (from washing, perspiration or other bodily exudates), or rubbing against clothing, and often fail to provide long-lasting benefits to the site of application. These water-containing emulsions are particularly unsuitable for overhydrated skin such as is under an absorbent article. Water-free creams or ointments are also known. Typically, these creams or ointments use oleaginous base such as petrolatum to provide the substantively of the creams or ointments for a long-lasting coating of the target areas.
In another approach, multi-ingredients lotion compositions are used. Various active ingredients have been incorporated into topically applied compositions to treat or prevent diaper rash caused by the prolonged contact of skin with bodily exudates. For example, to combat the irritants and protect or enhance the skin's barrier properties, a host of cosmetic or therapeutic skin care actives can be incorporated into a carrier and applied to the skin, either by hand or via a dispensing means. These active ingredients include barrier substances (such as zinc oxide), skin conditioning agents (such as lanolin), pH buffer substances, protease and/or enzyme inhibitors, and other active ingredients. Because these active ingredients are typically simple, low molecular weight compounds or mixtures, they are generally not applied alone, but in combination with a carrier system. Most typical carrier systems are emulsions having a water phase and an oil phase, such as O/W or W/O emulsions. Less common delivery systems are substantially anhydrous, oleaginous compositions. The oleaginous compositions are generally more substantive than the O/W or W/O emulsions; thus, they may serve as reservoirs from which the active ingredients are continuously delivered. However, they may not be efficient in delivering the active ingredients. This is so because many of the skin care actives are water-soluble or hydrophilic; thus, they exist as solid particles or powders in the oleaginous composition. These solid particles or powders are entrapped in the substantially anhydrous oleaginous base and cannot be easily released from the composition to the target skin surface. Moreover, even when these active ingredients are in contact with the target skin surface, they may not function efficiently in their solid form.
Therefore, it is desirable to have a substantive, non-irritating oleaginous composition that efficiently delivers water-soluble or hydrophilic skin care actives to the skin surface in their active form, which readily provide benefits to the skin. It is further desirable to provide an oleaginous composition from which the water-soluble or hydrophilic active is released more efficiently in its active form.
Moreover, it is desirable that the composition provides continuous and controlled release of the water-soluble or hydrophilic skin care actives from the oleaginous carrier system.
It is further desirable that in a preferred embodiment, this novel composition can be administered to the target skin area via multiple dispensing means, such as pads, bandages, patches, sticks, aerosol dispensers, pump sprays, trigger sprays, canisters, and absorbent articles. In this embodiment, it is desirable that the novel composition can be administered to the target skin without leaving a messy aesthetically unpleasing residue on the skin and without direct contact with the users' or applicators' hands, thus avoiding leaving a messy residue on the user's hands or requiring an additional cleaning step after administering the composition.
SUMMARY OF THE INVENTION
The present invention relates to a novel composition for efficiently releasing hydrophilic or water-soluble skin care actives from anoleaginous composition. Specifically, a hydrophilic-oleophilic release agent is incorporated into the novel composition to attract/absorb moisture which dissolve or solubilize the actives, and preferentially release the actives from the substantially oleaginous composition in their active forms.
A barrier protectant is also incorporated into the novel composition of the present invention. The barrier protectant, which serves as a substantially anhydrous carrier for the skin care actives and the release agent, is substantive. That is, it has a good staying power on the skin surface. It thus provides a coating over the skin to protect the skin against direct contact with bodily exudates, and against penetration by moisture or irritants that may result in skin irritation, inflammation, erythema, and other undesirable side effects. The barrier protectant coating also protects the skin against overhydration. Because of the good staying power of the barrier protectant on the skin surface, it may serve as a reservoir for continuous release of the skin care actives, and provide long-lasting skin benefits.
In one embodiment, the oleaginous composition of the present invention comprises: (1) at least one water-soluble skin care active; (2) a release agent having an HLB of at least about 3, preferably a nonionic surfactant, or a polymeric surfactant; and (3) a hydrophobic barrier protectant.
The novel composition of the present invention is suitable for topica

Affiliated with

Also associated with

Rating

Compositions for efficient release of active ingredients does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Compositions for efficient release of active ingredients, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Compositions for efficient release of active ingredients will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3232404