Prepreg is a pre-engineered laminating material manufactured by impregnating a fiber-reinforcement with a thermosetting or thermoplastic resin. Prepregs are widely used in the aerospace industry. The properties of prepregs are characterized in terms of their volatile content, resin content, the degree of pre-cure, void content, tack and flow ability. The two main methods used for producing thermosetting prepregs are hot-melt and solvent impregnations. In solvent-based prepreg processing, the most important processing parameters are temperature and pressure in impregnation bath, prepreg producing line speed and fabric tension. In hot-melt prepreg processing, prepreg properties depend on melt temperature, impregnation rollers pressure, temperature, and the speed of rotation. Usually, the goal is to obtain a prepreg with lowest void and the highest tack. Tack increase with increasing line speed and fabric tension, and decreasing impregnation temperature and pressure. In contrast, void content is decreased with decreasing the line speed and fabric tension, and increasing the impregnation temperature and pressure.