SURFACE ENERGY AND SURFACE CHARGE METER

摘要

A surface energy/surface charge meter (10) includes one probe (18) or two probes (18a-b). Each probe (18, 18a-b) has two spaced apart electrodes (38 and 40) with a centrally located fluid dispensing head (36) which dispenses a volume of electrically conductive fluid onto a surface of a material (22) having an unknown surface energy or surface charge. When a fluid of known surface tension is dispensed onto a material (22) having unknown surface energy, the surface energy is determined by the volume of a fluid drop (42) which bridges between the electrodes (38 and 40). When both a positively charged fluid and a negatively charged fluid are dispensed onto a material (22) using probes (18a-b), the surface charge of the material (22) can be determined from the electrical conductivity or resistance measurements made after the electrodes (38 and 40) have been bridged. After bridging the electrodes (38 and 40), the rate at which the positively and negatively charged fluids spread across the surface is a function of surface charge.