A low-impedance biological electrode device for establishing electrical connection between the human body and electrical recording or stimulating apparatus without the use of conducting fluids, such as, gels, pastes and electrolytes, comprising, a substantially planar relatively thin electrode body, having as the electrically conducting connecting unit contacting the human body, a plurality of individual longitudinally extending strands, fibers, or filaments of conducting material embedded in a pressure-sensitive or solvent-activated adhesive which serves to bond the strands together in a composite connecting unit and to bond the connecting unit on one side to said electrode body and on the other side or interface to the human body, a modification being the use of strands cross-oriented with respect to the longitudinal strands, as exemplified by woven conductive material, the connecting unit being provided with a transverse bus bar in the form of metal foil in electrical contact with an electrical connecting element for conducting current from the connecting unit in contact with the human body to the electrical recording or stimulating apparatus.
The invention relates to an electrode structure for measuring a biosignal from a living body, which electrode structure comprises a contact surface intended to be placed against the body. It is essential for the invention that the contact surface comprises several adjacent wave fronts, which wave fronts comprise protrusions and valleys, which are situated lower between the protrusions.
Electrode construction having a support structure. A conductive material is carried by the support structure. The conductive material has a length which is at least as great as its width.
An electrolyte gel matrix, which may be a conductive adhesive such as a urethane hydrogel, is located in a cavity formed in a non-conductive tray. The matrix is adapted to engage the skin of a patient and transmit signals between the skin and an electrode conductor supported by the base of the tray for exchanging signals with peripheral equipment. A stiffening platform adhered to the tray extends across the cavity portion aligned with the conductor to minimize motion artifacts associated with the use of the electrode. The electrode is removably attachable to the skin by an adhesive layer on the lower surface of the tray and by a preferably more aggressive adhesive layer on the lower surface of the platform.
Contact comprised of a mass of nonconductive material having a low durometer and conductive elements dispersed in the mass of material in sufficient quantity to establish contact between the elements to provide a resistivity in the range of 10 to 100 ohm-cm.
A skin adhesive hydrogel formed by mixing in aqueous medium: (A) major proportion of a high molecular weight water-soluble polyvinylpyrrolidone having ring opened pyrrolidone groups and (B) a minor proportion of a water-soluble multifunctional amine-containing polymer to form a water insoluble, water swellable cross-linked salt between carboxyl groups of the ring opened pyrrolidone groups and basic amine groups of the polyfunctional amine-containing polymer. The reaction is advantageously carried out in the presence of a plasticizer.
