IL111160A - Stimulating electrode structure - Google Patents

STIMULATING ELECTRODE STRUCTURE 1 111,160/2 The present invention relates to a disposable, water-impregnable adhesive cloth pad for an electrode/ skin interface.

Surface stimulation electrodes generally interface with the skin through a layer of a conductive liquid or gel. Commercially available electrode gel, or water with some salt content, such as saline, or tapwater, are often used to provide this interface. The gel is generally spread over the electrode surface, which is then placed onto the skin. A porous structure is often used to contain the conductive liquid. Sponge pads, and various open-structure polymers have been used for this liquid-carrying layer. The liquid and its porous supporting structure require periodic changing due to contamination by perspiration and bacteria.

The South African Patent 90/334635/44 describes an electric stimulation electrode composed of a self-adhering electrode stuck onto the skin surface with adhesive. The electrode has a layer of flexible solid conductive adhesive between the electrical shunt and the skin.

It is one of the objects of the present invention to provide a porous pad to serve as an electrode/skin interface, which pad holds a substantial amount of conductive liquid and is easily peeled off the electrode for replacement.

According to the invention, this is achieved by providing a disposable, liquid-impregnable adhesive cloth pad for an electrode/ skin interface, comprising a cloth pad impregnable with, and substantially retaining, an electrically conductive liquid and adapted to be mounted on selected locations on the skin of a patient, an electrically conductive electrode connectable to a stimulator for supplying stimulating impulses to said electrode, and at least one layer of an adhesive applied at least to a portion of said cloth pad, said at least one layer serving to removably attach said pad to said electrode.

The invention will now be described in connection with certain preferred embodiments with reference to the following illustrative figures so that it may be more fully understood.

With specific reference now to the figure in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

In the drawing: Fig. 1 is a perspective, partial cross-sectional view of the arrangement according to the invention.

Referring now to the drawing, there is seen a water-soaked pad 2 made from non-woven cloth, and covered by an adhesive layer 4. The adhesive should allow the stimulation current to pass through it, being either conductive in itself, or by only partially covering the cloth, e.g., being arranged in a striped or a dotted pattern on the cloth surface, or as a border around the edge of the cloth pad. The adhesive itself retains its adhesive properties when the pad is saturated with water. Manual pressure applied to the adhesive 4 between the pad 2 and the surface of a conductive electrode 6 activates the adhesive properties of the layer 4, resulting in firm attachment of the pad 2 to the surface of electrode 6. When required, the pad 2 may be removed by manually peeling it off the electrode 6. The adhesive layer 4 is designed, by virtue of its greater adherence to the cloth pad 2 than to the electrode 6, to separate from the latter and to be disposed of with the pad 2. A fresh pad/ adhesive can then be placed on the electrode 6. By means of a conductor 8, the electrode 6, advantageously a metal foil, is connected to the stimulator.

A further possibility for the intermediate adhesive layer 4 is the use of a compound layer, such that the properties of the adhesives are optimal for the two components they are required to glue together. For example, a commercial self-adhesive material (e.g., D-C-Fix, Konrad Hornschuch AG D-74679, Weissbach) can be glued to the cloth pad by a further cement (3M 90 High Strength Adhesive, 3M Co., St. Paul, Mn. , U.S.A.). The resulting compound layer ensures permanent adhesion to the cloth layer 2, while constituting a light, reappliable adhesive for bonding to the electrode 6, or to any surface behind the electrode and supporting it.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrated embodiments and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

WHAT IS CLAIMED IS: