NEW SOLVENT SYSTEM FOR THE IMPROVED ELECTROCHEMICAL PERFORMANCE OF SCREEN-PRINTED POLYURETHANE MEMBRANE-BASED SOLID-STATE SENSORS

In our previous work aimed at mass producing chemical sensors, we have used the fabrication techniques of semiconductor processing and scree n printing. In that work, we showed that high boiling-point solvents ( i.e., low evaporation rates) were needed to increase the membrane past e viscosity and thixotropy [1]. While this approach achieved a paste w ith good mechanical properties for screen printing, the resulting sens ors for some ions exhibited poor electrochemical performance in terms of detection limits and slopes. This paper reports a new technique usi ng a low boiling-point plasticizer, dimethyl phthalate (DMP), to contr ol viscosity in the membrane paste. Use of the plasticizer facilitates screen printing, while maintaining good electrochemical characteristi cs.