ABSTRACT   Plasma technologies present an environmentally-friendly and versatile way of treating textile materials in order to enhance a variety of properties such as wettability, liquid repellency, coating adhesion enhancing dye uptake, colour fastness; reducing textile finishing, printing costs, improving the bonding and adhesion properties of coated and laminated fabrics; sterilisation and optimizing biocompatibility essential for medical implants. Since their introduction in the 1960s, the main industrial applications of the low-pressure and low-temperature properties of plasmas have been in micro-electronic etching. In the 1980s, these uses broadened to include many other surface treatments, especially in the field of metals and polymers. This technology offers a versatile approach with the potential to overcome the cost and environmental problems associated with current techniques for modifying fabric surfaces. By appropriate choice of plasma composition and process conditions, it enables material surface characteristics to be tailored to meet specific requirements. This can be carried out under dry conditions and with neither high consumption of energy and raw materials nor pollution. The textile industry has long recognized that, for a large number of processes and applications, the surface properties are a key aspect of the product and often need to be quite different from those of the fabric bulk. In addition, these processes, in effect, treat the fabric bulk, something which is unnecessary and may adversely effect overall product performance. In this paper we are dealing with the plasma treatment process in textile and its working.     WHAT IS PLASMA? Plasma is an electrically conductive medium containing a gas of positive ions and electrons with little or no charge. When we increase the temperature of matter, it passes successively through its solid, liquid and gaseous states. But if we continue to heat it, it undergoes a further transformation of an altogether different kind. Collisions between particles of matter increase and the initial gaseous state, comprising neutral molecules or atoms, develops into an ionized state with an equal density of positive ions and negative electrons. This mix of charged particles is called a plasma and constitutes the 'fourth state of matter' commonly found in nature. TECHNOLOGICAL INNOVATIONS IN PLASMA SYSTEMS FOR TEXTILES However, the plasma technologies being exploited today use low-pressure plasmas, requiring closed, vacuum-system equipment, making them quite unsuitable for the continuous, room temperature treatment of fabrics on an industrial scale. Plasmas display significant advantages over wet chemical methods for surface modification of textile materials. Many commercial plasma processes perform surface fictionalization, graft and plasma polymerization, cleaning, and etching of a large variety of substrates. Most of these processes are conducted in vacuum systems. Atmospheric pressure plasmas eliminate the need for harsh chemicals or inefficient vacuum chambers that are limited to batch processes. The process is suitable for a variety of applications- include bonding composite materials, treating or sterilizing medical-grade plastics and metals, stripping organic contamination, removing oxidation, etching glass and silicon, and depositing films. The atmospheric pressure plasma generates a stream of reactive gas at low temperatures. However, the available plasma processes need substantial modification to make them suitable for handling open-width fabrics and for treatments at atmospheric pressure. OPERATING PRINCIPLE Atmospheric plasma technology, gas at atmospheric pressure is excited by means of a high voltage in such a way that plasma ignites. Compressed air then forces the plasma out of the nozzle. There are two different plasma effects: Activation and precision cleaning is carried out by the reactive particles contained in the plasma beam In addition, loosely adhering particles are removed from the surface by the compressed air accelerated active gas beam. Varying the process parameters such as treatment time and distance from the substrate surface allows the results of the treatment to be influenced in different ways.  In low pressure plasma technology, gas in a vacuum is excited by a supply of energy. Energy-rich ions and electrons are created along with other reactive particles that form the plasma.    TYPES OF PLASMA TREATMENTS There are basically two different types of plasma treatments. Ø     Low pressure treatments Especially suitable for treatment of 2D and 3D components Bulk materials can be treated and Batch processes is performed   Ø     Atmospheric pressure treatments Especially suitable for treatment of 2D components Can be integrated in existing automated systems and continuous processes possible One of the main differences between low-pressure and atmospheric-pressure plasma treatments is that there is little moisture involved in the low-pressure plasma treatment, although moisture could exist at the wall of the vacuum chamber or react with the substrate after plasma treatment, while in the atmospheric-pressure plasma treatment moisture exists not only in the environment but also in any hygroscopic substrate. MULTIFUNCTIONALITY IN TEXTILE APPLICATIONS "Unlike liquid processes which penetrate deep into the fibres, plasma produces no more than a surface reaction, the properties it gives the material being limited to a surface layer of around 100 Ao," These properties are very varied and can be applied to both natural fibres and polymers, as well as to non-woven fabrics, without having any effect on their internal structures. Plasma processing makes it possible to impart hydrophilic or hydrophobic properties to the surface of a textile, or reduce its inflammability. And while it is difficult to dye synthetic fabrics, the use of reactive polar functions results in improved pigment fixation. Finally, with plasma containing fluorine, which is used mainly to treat textiles for medical use, it is possible to optimize biocompatibility and haemocompatibility . A method for treating surfaces of textile is disclosed. A coating solution, in which a polymer with reactive groups is utilized to give various functions, such as hydrophobicity, anti-bacteria or hydrophilic (hygroscopicity) is formed. The coating solution with different viscosities, specially low viscosity, 100 cps or less, can be continuously coated onto a surface of the textile by employing a surface treating technique of gravure coating and appropriately adjusting the gravure meshes. After drying, a highly durable, washable and firm textile with single or multi-functions, such as outer hydrophobic surface and inner anti-bacterial and (or) hydrophilic (hygroscopic) surface.   WATER REPELLENT POLYARAMIDE FABRIC The data in the table demonstrates that a fluorocarbon plasma treatment can reduce the soaking of fabrics in a similar way like a traditional impregnation. However, in contrast to the wet treatment, the fabric retains its flexibility after the plasma treatment. Treatment Water absorption,% non 52 wet 19 plasma 19   WATER REPELLENT COTTON, HEMP Cotton or hemp fabric usually absorb water immediately. Applying a low-pressure plasma process, the fiber's surface can be altered to make it repel water. After the treatment, drops run freely over the surface while mechanical properties, the visual appearance, and the permeability for water vapor remain unchanged. The surface modification is limited to a very thin layer. A treatment as short as 2 seconds can be sufficient to achieve this effect in a batch process. Continuous treatments with a speed of more than 20 m/min are conceivable.                                         Drops of an aqueous dye                     Stains of aqueous dye solutions on        hydrophobic cotton                                       solutions on ordinary cotton   The stability of the modification can be seen in intermitted washing cycles of fluorocarbon treated cotton fabric. After an initial drop, the finishing remains stable for at least two hours at 95°C. The quality of the repellent effect is evaluated by putting water drops to the fabric surface. A value of 1 means that the drops run freely over the surface and do not penetrate into the material while at a value of 3 the water drops does not penetrate but it needs vibrations to move the drop. Obviously this evaluation depends also on the nature of the fabric.   WETTABILITY IMPROVEMENT In oxygen plasma the number of functional groups at the surface can be increased. The increased polarity makes the material more wettable which can be used to improve dying and sizing.   The effect of the treatment was checked by a water rise test, i.e. a strip of the fabric was put into water end the time was measured until the water rise up 3 cm. Water rise time (s):   Material Untreated Treated Treated, after 80 days PA 1 96s 16s 18s PA 2 18s 7s 10s PA 3 558s 51s 78s   PROTOTYPES DEVELOPED 1.     products to evaluate the effect of the process on cotton and cotton-polyester woven fabrics, car upholstery polyester fabrics and wet-laid non-wovens. 2.     assess whether plasma treatment would eliminate problem of felting in woollen fabrics. 3.     adhesion characteristics of polypropylene fabrics could be improved. 4.     testing the effects of plasma treatment on various specialised fabrics, used as paper-machine clothing ATMOSPHERIC PRESSURE PLASMA JET PROCESS APPJ surface treatment can be done in either a downstream or an in-situ mode. Typically, the in−situ approach is preferred, because it requires less gas flow and consumes less power. The downstream process requires a greater gas flow to carry a flux of reactive species from the jet to the substrate surface. In the in-situ process, the reactive species are formed in proximity to the substrate surface, and gas flow is needed only to replace the active species that are consumed in the chemical reactions on the surface. Helium recycling can mitigate gas consumption for both the downstream and the in-situ modes of operation. For example, the APPJ technology has been used to defluorinate a PTFE surface, making the inherently hydrophobic surface wettable. This capability is critical for printed circuit board applications, as well as adhesive tapes. The surface properties alterations obtained by a plasma treatment are complex in nature. Particle induced reactions take usually place in the upper ten nanometers of a surface. Short wavelength UV-radiation as it is emitted by low pressure plasmas initiates reactions in a thicker layer (about 100 nm). The relation between the two and the extent of both can be controlled by the process gas and other process parameters. The outermost surface, only some atom layers, sometimes less than 1 nm, determines the interaction with other media. The chemical composition of this part of a fiber is responsible for good or bad adhesion in laminates or whether the fabric is suitable for impregnation or not. PROCESSING DIFFICULTIES Some of the scientific interests group are primarily                              concentrated on the following problems Ø     Interaction of non-equilibrium vacuum plasma with polymer films and fabrics. The use of plasma to modify the properties of polymer film and fabric. The creation of engineering methods for plasma chemical reactors calculations and for the optimization of modification processes; Ø     Kinetics of homogenous oxidation processes initiated by quasi-stationary plasma in electrolyte solutions involving organic, inorganic substances and dyes. The nature of plasma-generated oxydizing agents, the mechanisms and kinetics of the processes of the formation and transformation of these agents, the interactions                    between       primary and secondary particles; Ø      Processes of modifying and finishing textile polymeric materials in plasma activated solutions; Ø     Mechano-chemical treatment of fibrous materials in solutions in the conditions of impulse plasma application ADVANTAGES Clean and efficient technology. The traditional liquid chemical processes used by the textile industry involve high consumption - and pollution - of water resources. Waste-processing costs are also high and drying the processed fibres uses a lot of energy. This makes "dry" processing using plasma technology all the more attractive - especially for the environment. In addition, the speed of the process (just a few minutes, or even seconds) reduces energy consumption still further. In addition, no significant difference in single fiber tensile strength is observed after the plasma treatments at all moisture levels. Therefore, it is concluded that the environmental moisture did not significantly influence the effect of atmospheric-pressure plasma treatment in improving interfacial bonding between the fiber and epoxy resin in a composite. The improvement of the interfacial shear strength for the plasma-treated samples at all moisture levels could be mainly due to the increased surface roughness and increased surface oxygen and nitrogen contents due to the plasma etching and surface modification effect. Non-thermal atmospheric pressure plasmas offer the obvious advantages of eliminating the cost and complexity of operating under vacuum. Atmospheric Pressure Plasma System has no moving parts. There are no moving parts for maintenance-free operation and setup can be completed in 10 minutes.It delivers consistent and uniform treatment for improved reliability and quality. DISADVANTAGES  Beating the vacuum "Despite all these significant benefits demonstrated in the laboratory, plasma processing has failed to make an impact in the textile sector because of a particular constraint which is incompatible with industrial mass production,". "All the technologies developed to date are based on the properties of low-pressure plasmas. The process must take place in an expensive, closed-perimeter vacuum system and cannot be used for production lines operating at room temperature, with machines processing fabric 2 metres wide at high speed." DEVELOPMENTS Development of technology offering comparable performance at ambient pressure to that of "glow discharge" plasmas requiring a partial vacuum. studying the industrial feasibility of APPS technology and conducting full-scale tests to determine the relationships between the physical properties of different types of plasma and the results obtained, as well as the way the plasmas interact with various materials. Ø     specialising in the adhesion of polymer coatings and automobile textiles Ø     testing plasma technologies as a possible way of eliminating felting   Ø     to improve the binding properties of polypropylene-based coatings Ø     products for the printing and textile industries. CONCLUSION "There are only two or three systems utilizes plasma at atmospheric pressure currently at the development stage - in Japan and the United States - but no wide-ranging application for the textile sector is available yet. So the prospects are extremely promising." From the stars to industry Development of technology offering comparable performance at ambient pressure to that of "glow discharge" plasmas requiring a partial vacuum. studying the industrial feasibility of APPS technology and conducting full-scale tests to determine the relationships between the physical properties of different types of plasma and the results obtained, as well as the way the plasmas interact with various materials. Ø     specialising in the adhesion of polymer coatings and automobile textiles Ø     testing plasma technologies as a possible way of eliminating felting. Ø     to improve the binding properties of polypropylene-based coatings Ø     products for the printing and textile industries. The textile industry has long recognised that, for a large number of processes and applications, the surface properties are a key aspect of the product and often need to be quite different from those of the fabric bulk. In these aspects the plasma systems find their extensive applications, what it needs is the development with research. REFERENCES: I      THE “ TEXTILE RESEARCH JOURNAL” may 2007.