Surgery: splint – brace – or bandage – Bandage structure – Skin laceration or wound cover
Reexamination Certificate
1999-03-19
2001-05-01
Lewis, Kim M. (Department: 3761)
Surgery: splint, brace, or bandage
Bandage structure
Skin laceration or wound cover
C602S041000, C602S043000, C602S055000, C602S057000
Reexamination Certificate
active
06225521
ABSTRACT:
The present invention relates to a patch for temporary application to the skin to exert a cosmetic and/or pharmaceutical treatment action thereon.
BACKGROUND OF THE INVENTION
Patches are known that comprise a backing sheet coated on one face in a layer forming a reservoir known as a “matrix”, containing one or more active substances that are to be diffused into the skin and/or that are to act thereon.
The matrix can be made of a material having adhesive properties, whether intrinsic or otherwise, in which case the patch has an adhesive coating on its surface.
In which case, it is necessary to ensure that the coating does not impede the action of the active substance(s) contained in the matrix.
The invention relates more particularly to a patch in which the matrix is made of a material presenting intrinsic adhesive properties.
Selecting this material raises difficulties, and in particular:
it must be capable of containing the active substance(s) for acting on the skin;
its adhesion to the skin must not be too strong, particularly if it is to be applied in repeated manner, since otherwise the region of the body on which the patch is applied will be come irritated, and removing the patch will become painful;
its adhesion must not be too weak either, since otherwise it will not be able to adhere to the skin if it is moist or if it becomes moist, e.g. because of sweating;
it must be sufficiently flexible to allow the patch to fit over the shape of the region of the body on which it is applied;
it must remain on the backing sheet when the patch is removed; and
finally, it must make it possible to extract the impurities that are to be found on the surface of the skin, in particular sebum or sweat.
In spite of these difficulties, several materials have been proposed for making the matrix, however they are not necessarily suitable for all of the active substances that it might be desirable to incorporate therein.
French patent 2 738 744 or European patent 0 309 309 teach in particular the use of hydrophobic or hyposoluble materials for constituting the matrix.
The hydrosoluble material described in European patent 0 309 309 is relatively impractical in use since it does not present the required adhesive properties prior to application to the skin and it requires the skin to be previously moistened.
European patent application EP-A-0 412 869 describes a composite film having a silicone polymer matrix adjacent to an occlusive matrix. On its side remote from the occlusive layer, the matrix has a reinforcement—constituting screen and a removable protective membrane. The screen reduces the adhesive area of the protective membrane on the matrix.
In such a composite film, the screen locally prevents the matrix from coming into contact with the skin. When the film is withdrawn, the screen runs the risk of leaving a mark on the skin with the mark being all the more pronounced with increasing adhesion of the material constituting the matrix. For a silicone polymer matrix, whose adhesive power (TAC) is relatively low (about 100 g/cm
2
), this drawback is nevertheless not too troublesome. Finally, the screen prevents a mechanical cleansing action being exerted on the entire area of the skin that is covered by the film.
OBJECTS AND SUMMARY OF THE INVENTION
The present invention seeks to facilitate selecting the material constituting the matrix, but without thereby complicating use of the patch.
This is achieved by the invention by a novel patch comprising a matrix made of a material having self-adhesive properties prior to application to the skin, the patch including a permeable structure completely embedded in said matrix close to its surface so as to modify its overall adhesive power.
Preferably, the permeable structure is hydrophobic.
Also preferably, said permeable structure is constituted by a perforated film, or a solid-fiber cloth that may be woven or non-woven.
When using a hollow fiber cloth, the porosity of the fibers is preferably selected so that they are filled substantially completely by the matrix.
Thus, the permeable structure is not suitable for absorbing moisture present on the skin or the active agent that may be present in the matrix. There is thus no risk of these agents accumulating in the permeable structure, which could delay diffusion thereof into the skin.
Preferably, the permeable structure used is selected so as to present little ability for elongation in the long direction of the patch, so as to make the patch easier to unstick.
Because of the invention, it is possible to control the adhesive properties of the patch on the skin by acting on the nature of the permeable structure used and on the thickness of the matrix situated between the permeable structure and the surface that is to be applied against the skin.
This way of acting on the adhesive properties of the patch make it possible to use a material for making the matrix where, in the absence of said permeable structure, the material would otherwise adhere too strongly to the skin to be suitable for making the looked-for patch.
Thus, by means of the invention, any novel material having intrinsic adhesive properties and that is of interest because of its physical and chemical compatibility with the active substance(s) to be incorporated therewith can be used without any fear of excessively strong adhesion to the skin.
In addition, the permeable structure used makes it possible for the active substance(s) contained in the matrix to diffuse and/or act towards and/or onto the surface of the skin.
Because the permeable structure used for modifying the adhesive power of the matrix is completely embedded in the material constituting the matrix, it is possible to exert mechanical cleansing action over the entire area of the skin covered by the patch, if so desired, since the entire area of the patch that is to come into contact with the skin is adhesive. The risk of leaving a mark on the skin having a pattern corresponding to that of the permeable structure used is also reduced. Finally, when active substances are contained in the matrix, they can exert their action over the entire area of the skin which is in contact with the patch, whereas in European patent application EP-A-0 412 869, the screen applied directly on the skin hinders diffusion of the active agents into the skin, to some extent.
REFERENCES:
patent: 0 309 309 A1 (1989-03-01), None
patent: 0 353 972 A1 (1990-02-01), None
patent: 0 412 869 A1 (1991-01-01), None
patent: 0 413 034 A1 (1991-02-01), None
patent: 0 651 984 A2 (1995-05-01), None
L'Oreal
Lewis Kim M.
Oliff & Berridg,e PLC
LandOfFree
Adhesive-matrix patch does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adhesive-matrix patch, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adhesive-matrix patch will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2517824