L^ONJiij/aJ EFFECT OF SOFTENERS ON COLOUR FASTNESS OF REACTIVE DYES D S FERNANDO A dissertation submitted to the Department of Textile & Clothing Technology of the University of Moratuwa in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN TEXTILE STUDIES oS DEPARTMENT OF TEXTILE & CLOTHING TECHNOLOGY UNIVERSITY OF MORATUWA SRI LANKA S E P T E M B E R 2005 T f c e g University of Moratuwa Q /Jj• fl "71 84170 DECLARATION The work presented in the dissertation in part or whole, has not been submitted for any other academic qualification at any institution. D S Fernando Mr. V A Nandasena (Candidate) (Supervisor) A B S T R A C T This research project is primarily aimed to study the influence of softeners on colour fastness and shade variation of cotton fabric dyed with bi-functional reactive dyes. The commercial dyes selected for the study contained, both the fluoro triazine and vinyl sulphone reactive groups, in the same molecule. Four different shades of the CIBACRON FN reactive series were applied on 100% cotton knitted fabric by exhaustion method. Each fabric piece dyed was subsequently subject to the treatment by a softener. This was followed by the assessment of colour fastness ratings for washing, light and Rubbing. Light fastness was assessed subjectively with the blue wool standard and is further confirmed objectively with the help of the spectrophotometer. The fastness ratings were compared with the softner-free samples of the same shade. This study has revealed that the treatment with softeners has resulted in a general improvement in wash and light fastness properties Polyethylene emulsion has adversely affected washfastness irrespective of the shade. A significant reduction in the light fastness was evident when treated with cationic softeners. The dye, CIBACRON BRILLIANT BLUE FN-G has shown peculiar reduction in light fastness following treatment with all types of softeners. In addition to the above, certain other trends and patterns have also been noticed when analyzing the data collected. TABLE OF CONTENTS Page 1. Introduction 1 2. Literature Review 3 2.1 Dyeing with Reactive Dyes 3 2.2 Reactive Systems 6 2.2.1 Mono functional Systems 7 2.2.2 Bifunctional Systems 10 2.3 Reactive Dye-fibre Bond 13 2.4 Fastness properties and reactive dyes 17 2.5 Light fastness of reactive azo dyes 18 2.6 Softening of Textiles 20 2.7 Instrumental Colour Assessment 27 3. Methodology 29 3.1 Materials 29 3.2 Method 29 4. Results Data & Observations 32 5. Analysis & Discussion of Results 37 6. Conclusions & Recommendations 41 7. References 54 • LIST OF FIGURES, TABLES AND ANNEXES Figures Page 2.1 Rate of reactivity of triazines 4 2.2 Nucleophilic addition to vinyl sulphone 7 2.3 Amino fluoro-s-triazine dye 9 2.4 CI Reactive Black 5 10 2.5 CI Reactive Red 194 12 2.6 Reaction of cellulose with dichlorotriazine 13 2.7 Reaction of cellulose with aminoclorotriazine 14 2.8 Dye fibre bond formation by nucleophilic addition mechanism 14 2.9 Silicone emulsions 26 2.10 Structural formulas of amino/amido silicones 27 Tables 4.1 Change in colour of the specimen 32 4.2 Staining of the adjacent fabric 33 4.3 Light fastness ratings & shade differences 34 4.4 AL, Aa, Ab, AC & AH values of samples 35 4.5 Rub fastness ratings (Dry & wet) 36 Annexes 1 Reactive systems 42 2 Fixation of bireactive dyes on cellulose 44 3 Properties and application of softeners used 47 4 Light Fastness Assessment 52 ACKNOWLEDGEMENT At the outset I am very grateful to Mr. V A Nandasena, Chairman/Managing Director, Vantex (Pvt) Ltd., Dehiwela and Visiting Lecturer of the Department of Textile and Clothing Technology, University of Moratuwa, who is also the Project Supervisor, for the invaluable guidance and the encouragement given to me with extreme patience and understanding. I also wish to express my gratitude to Mr. K. Amaratunga and Ms. S. Dassanayake of Textile Training and Services Centre (TTSC) for their valuable assistance given in the preparation and analysis of samples, subject for the test. I also offer my most grateful thanks to Mr. A. Tennakoon of A Baurs & Company Ltd. for providing me the chemicals required for the study. Last but not least to Ms. P. Pemaratna at Sri Lanka Standards Institution for type setting the manuscript very efficiently. Finally I wish to extend my appreciation to my colleagues and close associates who guided and assisted me in numerous ways.