Pressure-sensitive conductive composite materials have good pressure sensitivity and conductivity. There are so many potential applications in intelligent packaging. In this article, we discussed the difference and relation between pressure-sensitive conductive materials and typical conductive materials; what is more, the definition and the principle of piezoresistive effect are also included. The piezoresistive effect has been divided into two parts by resistance and pressure: positive piezoresistive effect and negative piezoresistive effect, respectively. The application of the two effects is also discussed. In our laboratory, we have prepared pressure-sensitive conductive microcapsules, in which Ag particles are as the core, the size of as prepared mierocapsules is around 100 mu m, with the pressure effect, the microcapsules show excellent pressure sensitivity and conductivity.
