Treatment of Cotton Fabric with Dielectric Barrier Discharge (DBD) Plasma and Printing with Cochineal Natural Dye

Objectives: Plasma is used in this study to activate the surfaces of cotton fabric and its blend with polyester using dielectric barrier discharge (DBD). The aim of this work is inserting new characteristics to the activated fabrics’ surfaces to be printed with natural dyes extracted from the raw dried and pulverized bodies of cochineal insects. Methods: The dye extraction is carried out using two techniques; conventional or ultrasonic. The changes induced in wettability, tensile strength and printability of cotton and polyester/cotton are given. Scanning Electron Microscope (SEM) characterizes surface morphology of the treated fabrics. The chemical groups deposited on the activated fabrics’ surfaces by plasma treatment are characterized using Atomic Force Microscope (AFM). Finding: The dye extraction affected by three factors; 1. Temperature, 2. Extraction time, 3. The extraction technique. With increasing the temperature the extractability increases and the absorbency reached 1.98 mg g^-1 at 80°C on using (US) technique whereas, it was only 1.63 mg g^-1 on using (CH) at the same temperature. Maximum dye extraction was attained using US method at power 500 W and time 60 min. O_-1sup>- plasma treatment increases the color strength of cotton and PE/cotton fabrics, compared to the intensity of the same two fabrics treated with air- plasma. Increasing plasma exposure time from 3 to 10 min and discharge power from 3 to 15 W decreases the wetting time of the treated fabrics and this leads to higher wettability.SEM images showed smoother surface for untreated cotton and polyester/cotton samples compared to the air plasma and oxygen plasma treated samples. Improvement: The treatment improved wettability, the printability and fastness properties of the treated cotton and polyester/cotton fabrics using Cochineal natural dye.