Abstract An ion-selective electrode having its ion-transfer membrane sealed about its periphery with an elastomeric material free of fissures, voids and bubbles, thereby providing an electrode which responds almost instantaneously to a change to potential at the test solution-membrane interface. The preferred sealant is a room temperature vulcanizing silicone rubber bonded to the crystal with the aid of a silicone primer. The invention also contemplates a membrane (substitute crystal) made from compacted microsize ion-transfer particles in which each of the tiny particles in the membrane face which contacts the test solution is coated with an elastomeric water impervious film e.g. a room temperature vulcanizing silicone rubber.
The ion-selective electrode membrane of claim 1 wherein said sealant is a room temperature vulcanizing silicone rubber.
Claim 2
Dependent Claim
23 words
The ion-selective electrode membrane of claim 2 where said binding means comprises intercrystal adhesion effected by high pressure during formation of said compact.
Claim 3
Dependent Claim
124 words
An ion-selective electrode characterized by rapid response to a change in potential over a wide temperature range comprising a tubular stem molded from insulating plastic having a recess in the lower end thereof an ion-transfer membrane mounted within said recess and bonded thereto by an annular sealant strip of silicone rubber free of fissures said membrane comprising compacted microsize ion sensitive particles bonded together by a rigid resin and having an elastomeric sealant filling the spaces between each of the particles in the liquid-contacting face of the membrane, said sealant strip being adhered to the periphery of said membrane in liquid-impermeable relationship, and an electrical conductor connected to the inner face of said membrane and extending through the upper end of said tubular stem.
Claim 4
Dependent Claim
94 words
An ion-selective electrode characterized by rapid response to a change in potential over a wide temperature range comprising an ion-transfer membrane mounted in the end of a hollow nonconducting electrode body and an insulating seal made from vulcanized silicone rubber binding the periphery of said membrane to said body, said seal completely filling the space between said membrane periphery and said body and being free of discontinuities or gaps at the interface with said membrane, the bond between the membrane and the seal being stronger than the bond between the seal and the body.
Claim 5
Dependent Claim
18 words
The ion-selective electrode of claim 5 in which said membrane periphery is coated with a silicone rubber primer.