I hereby declare that this project (Thesis) report was prepared by me under the guidance of Md. Therefore, it will be highly appreciated if you kindly accept this project report and consider it for final evaluation. At the outset, I express my heartfelt thanks and gratitude to the Almighty for the divine blessings that enable the successful completion of this project.
Kamrul Islam, Lecturer, Department of Textile Engineering, Faculty of Engineering, Daffodil International University for his in-depth knowledge and keen interest in the field of textile pre-treatment, dyeing and finishing, guided me to execute this project smoothly. His endless patience, careful guidance, constant encouragement, constant and energetic supervision, constructive criticism, valuable advice, reading many inferior drafts and correcting them at all stages have made it possible to finally complete this project. Mominur Rahman Sir, Assistant Professor, Head of Department of Textile Engineering, Daffodil International University, for his continuous guidance in preparing this project report.
I would like to thank my coursemates from Daffodil International University who participated in the discussions while completing the course. Conventional wet processing methods for textiles require a series of treatments that require a huge amount of water. The traditional method of pre-treating cotton (scouring and bleaching) and dyeing requires a lot of water and chemicals, resulting in a huge amount of toxic waste water, with very barbaric consequences for the environment.
To reduce the cost of textile pre-treatment and introduce a sustainable and environmentally friendly pre-treatment method.
Chapter- 2 Literature Review
The term 'pre-treatment' means treating something with some kind of chemical before use. The textile pre-treatment process can help eliminate sizing agents, oils, waxes, seed husks, soils, pectin and other impurities while improving the whiteness and feel of the fabric. It helps to remove natural and additional impurities from the textile material such as: oil, wax, soil, dust, dirt, broken seeds, dried leaves, grease, etc.
By removing impurities, the material is ready for further processes such as bleaching and dyeing. Bleaching is a process by which we remove the natural color of the textile material and provide it with permanent whiteness. Basically, it is the application of a dye to a textile substance such as fiber, yarn, fabric or garment in order to achieve the desired colored material with the appropriate properties.
The dyeing method can vary depending on the nature of the materials, but the most common and popular method is by immersing the material in a dye bath, maintaining the standard M:L (material : liquid) ratio. Textile materials are colored by creating a short bond between the dye particles and the molecules of the materials (apart from the pigment, a binder is required to create the bond). Dyes are usually used in solution and can be attached to the material and colored.
The dye should be chemically stable so that the color does not wash out with soap or detergent, should not fade when the dyed material is exposed to sunlight, etc. These types depend on the origin of the dyes, the source of the dyes and the solubility in water. of dyes, etc. In other words, it is the resistance of the color of a finished textile material to destructive factors such as washing, rubbing, perspiration, saliva etc.
For this reason, higher color fastness properties are essential for all textile materials to ensure their purpose. During production and end-use by consumers, textile products can be subjected to considerable stress, resulting in color changes such as color fading, color fading, color bleeding, etc. These factors are usually unwanted by producers or consumers, therefore it is very important to determine the color fastness of textile materials at a very early stage [4].
Chapter- 3 Materials & Method
To do the sanding and bleaching with soapnut, I had to use the two-bath method. In the first bath I did the scouring with different concentrations of soap nut, and in the second bath I did the bleaching. I took those samples and immersed them in the dye pot, where the dye solution is already poured.
I marked them with small cutouts on the edge of each pattern for identification. For dye chemicals I used Glauber's salt (electrolyte), Neocrystal BC-4500 (leveling agent), Seraquest W-CON-XC (sequestering agent) and reactive dye. Then I dye the sample at 60 ̊ C for 20 minutes, then add caustic soda and let it work for another 40 minutes.
Color fastness to washing is the most common test of color fastness, it refers to the resistance of a colored textile material to change its shade during washing with a soap (detergent). I took multi-fiber fabric of the same 10×4 cm size as the test sample and sewed the multi-fiber fabric and my test sample together at the end with a sewing machine. I put the test sample with the solution in the machine pot with 25 stainless steel balls and start the process.
After the washing process was completed, I did a cold wash on the test sample, and then it was dried in the laboratory incubator oven. Color fastness to rubbing stands for a color's resistance to wear or stains against another material. The test is carried out in two ways, one in dry condition and the other is in wet condition.
First I took my test sample and placed it in the sample mounting section of the machine. Then the machine finger is lowered onto the attached sample and the machine is turned on to continue the test. Then the test tissue is collected from the machine finger and the authenticity data is measured by gray scale.
Color variation is compared between the conventionally pretreated sample and the sample scoured using soap nut with the same dyeing conditions. The test is performed using CCMS- Computer Color Matching System with computer color machine.
Chapter- 4 Result & Discussion
The most common and popular way to know if a cleanse is good or not is the weight loss test. 𝑆𝑎𝑚𝑝𝑙𝑒 𝑤𝑒𝑖𝑔ℎ𝑡 𝑏𝑒𝑓𝑜𝑒 𝑠𝑐𝑜𝑢 cleaned with different concentrations of soap nut solution are,. The color fastness to friction or fastness to rubbing of a fabric determines the degree of color that can be transferred from a dye sample to the test fabric due to the force of friction.
From the table, it is clear that both samples show very good resistance to excellent friction in the drying process (4-5). Here the conventionally pretreated and dyed sample shows better performance than those sample cleaned samples. NOTE: In the table below, C refers to the conventional method and SN refers to different soap nut concentrations].
Color fastness to washing or fastness to washing is the resistance of a dyed material to a change in any of its color characteristics due to washing with any soapy agents or detergents. The dried samples are then evaluated against the main sample using gray scale. In this study, both types of samples are dyed with the same dyeing recipe, but introduced by two different pretreatment methods.
It can be clearly seen that the samples sanded with soap nut are lighter in color. Spectrophotometer is an instrument used to calculate the reflectance of visible light, UV light and infrared light. From this experiment, I found that if we use 6 g/l (5% stock solution) of soap nut for scouring 100% cotton single jersey fabric and then dyed, the desired shade can be obtained.
Chapter- 5 Conclusion
During my research I came to the conclusion that soap nut can actually be used as an alternative to synthetic detergents. But it is best suited for washing purposes and not as a means of pre-treating textiles, because it causes hydrolysis during the dyeing period, resulting in an uneven shade over dyeing. Finally, I would like to say that soapnut can be a sustainable and cheaper alternative to synthetic soap or detergent and it has the potential to act as an abrasive if the right method is used and with some adjustments in dyeing technique it can solve the hydrolysis problem during dyeing. are being solved. the dyeing can hopefully be removed.
