The first three states of matter are solid, liquid, and gas, and matter transitions from one state to the next by the addition of energy (often in the form of heat). For example, “solid” water is ice and melts into water with the addition of heat (energy). Water is evaporated into a gas with the addition of more heat. Plasma occurs after the gas state, with the addition of more energy. When molecules of the gas are given energy in excess of their ionization potential, electrons are able to escape the electron cloud. This results in a body of positively charged ions and negatively charged electrons. These charged species can be affected by electric and magnetic fields, resulting in the production of additional excited species.
Plasma exists in many everyday forms. The glow from neon signs is a plasma, as are lightening bolts. Flames, lasers, and most of “outer space” are also plasma. In general, plasma is classified by two factors, electron number density and temperature. Electron number density refers to the number of molecules that have ionized (lost one or more electrons) relative to the number of neutral gas species. “plasma temperature” is a bit confusing and does not refer to whether a plasma feels hot or cold, but rather to the energy (in the units eV) of the free electrons. If there are significantly more neutral gas molecules than ionized gas molecules, the plasma may be cold to the touch, but still have very energetic electrons and thus a very high plasma temperature.
Chemically active species can be produced by plasma if the proper conditions for generating plasma are chosen and the correct gases are selected. APJeT™ is an expert in selecting gases and designing systems to maximize the production of these chemically active species and engineering them for the finishing of fabric and other substrates.