US 4352359

Patent Overview: US 4,352,359 — "Biomedical Electrode"

Source: https://patents.google.com/patent/US4352359/en

Bibliographic data (per supplied text): US Patent 4,352,359; application US06/155,191; filed 1980-06-02; granted/publication date 1982-10-05; prior art date (priority) 1977-08-19; inventors Franklin C. Larimore and Steven M. Heilmann; original assignee Minnesota Mining and Manufacturing Co.; current assignee listed as 3M Co; status "Expired – Lifetime," anticipated expiration 1999-10-05.

Purpose: The invention relates to disposable "biomedical" electrodes that establish electrical connection between human skin and an electromedical apparatus (e.g., high-impedance electromyograph, electrocardiograph, electrostimulator for pain relief). More particularly, it concerns "dry" bioelectrodes that avoid messy creams or gels. The stated aim is an improved, essentially dry, disposable electrode that reduces skin irritation, avoids water-retention packaging, leaves no residue, and needs no costly electrode-plate surface treatment (e.g., silver/silver chloride) for defibrillation.

Plain-language scope: The electrode has an electrode plate with means for electrical connection to electromedical apparatus on one surface and, on the opposite body-contacting surface, an electrically conductive material. That material comprises a dermally non-irritating, conformable, cohesive, synthetic, hydrophilic polymer containing at least 5 mole-percent of monomer units containing a salt of a carboxylic acid. The electrode reportedly has an impedance of 500 Kohms or less at 10 Hertz. "Conformable," "hydrophilic carboxylate-containing polymer" (weight-average molecular weight at least about 10,000, preferably 100,000), "synthetic," and "cohesive" are expressly defined. Suitable polymers include water-soluble carboxylate-containing polymers (Class A), prepared by homo- or interpolymerization of carboxylate salts from Group I metal hydroxide acid-base reactions.

Note — the excerpt does not establish: the full text of the claims; details of the remaining polymer classes (only Class A is introduced before the excerpt ends); the complete listing of cited prior-art patents; or the specifics of any litigation, assignment, validity, or status beyond what the excerpt states. The excerpt also stops mid-sentence, so the enumerated polymer classes are incomplete.