Dermal sensing package and use

A sensor apparatus in the form a substantially flat package for receiving and transmitting electronic signals, to be monitored or recorded, comprising in combination:

• a) a first horizontal layer consisting of hydrogel and having opposite ends,
• b) a second layer co-planar with the first layer and having spaced apart sections projecting horizontally endwise oppositely relative to first layer opposite ends, and consisting of hydrocolloid, said sections being in endwise contact with said first layer opposite ends, and defining junctions therewith, said first and second layers having the same thickness, at said junctions whereby said opposite ends of the first layer are everywhere adjacently enclosed by ends of said second layer eliminating all open space therebetween, the two layers being in adjacent end-to-end contact throughout the thicknesses of both layers,
• c) a thin electrically conductive horizontally extending third layer directly overlying and having extensive surface to surface contact with the top of the first layer, and located above the level of the second layer said third layer being a single layer having everywhere the same total thickness which is substantially less than the thickness of each of the first and second layers, all of the first layer being directly below the third layer, said third layer having opposite ends that extend to said junctions of said first layer opposite ends with said second layer sections,
• d) an electrical lead in contact with the top of said thin conductive layer, and extending horizontally to the exterior of said layers, there being phthalate-free insulation on said lead, said third layer being the only layer between said lead and said first layer,
• e) adhesive adhering end wires of the lead to the top of said thin conductive layer,
• f) a protective cover layer which is insulative extending over said first, second and third layers, and over said lead,
• g) release liner extending at the bottom surfaces of the first layer and the second layer sections, and adhered thereto,
• h) said first layer and second layer sections having co-planar bottom surfaces defining a continuous tacky lower surface engaging said release liner,
• i) and said first layer and second layer sections having co-planar top surfaces defining a continuous upper surface, the top surface of the first layer engaged by said third layer between said first layer opposite ends, said first, second and third layers being radiolucent,
• j) said first, second and third layers located at the underside of the lead.