Chemical Technology in the Pre-Treatment Processes of TextilesBy
- S.R. Karmakar, College of Textile Technology, Serampore, Hooghly, West Bengal, India
Textile chemical processing today, particularly the pre-treatment processes require a highly sophisticated technology and engineering to achieve the well known concepts of "Right first time, Right everytime and Right on time" processing and production. Chemical pre-treatment may be broadly defined as a procedure mainly concerned with the removal of natural as well as added impurities in fabric to a level necessary for good whiteness and absorbency by utilising minimum time, energy and chemicals as well as water.
This book discusses the fundamental aspects of chemistry, chemical technology and machineries involved in the various pre-treatment process of textiles before subsequent dyeing, printing and finishing. With the introduction of newer fibres, specialty chemicals, improved technology and sophisticated machineries developed during the last decade, this book fills a gap in this area of technology. However, its real strength is its clear perception of ample background description, which will enable readers to understand most current journals, thus staying abreast of the latest advances in the field.
For teachers and students in the chemical textile industry.
Textile Science and Technology
- Preface. Kinds of Fibres. Introduction. Classification of fibres. Chemical composition, morphology and structure of cotton. Natural protein fibres. Long vegetable fibres. Regenerated natural fibres. Synthetic fibres. Miscellaneous synthetic fibres. References. Preparation before Chemical Processes. Introduction. Inspection. Sewing. Mechanical cleaning of fabrics. Singeing. Process sequence. Desizing. Introduction. Methods of desizing. Desizing of synthetic fabrics and their blends. Desizing machineries. References. Scouring. Introduction. Mechanism of removal of impurities. Scouring of cotton in alkaline agents. Surfactants. Solvent scouring. Scouring of raw wool. Scouring wool yarn and fabric. Carbonising of wool. Degumming of silk. Degumming of remie. Scouring of linen. Scouring of jute. Scouring of synthetic-polymer fibres. Scouring of blended fibre fabrics. References. Scouring Machineries. Introduction. Batch type (rope) scouring machines. Batch type (open-width) scouring machines. Semi-continuous scouring machines. Continuous scouring machines. Wool scouring machines. Silk degumming machines. References. Bleaching of Textiles. Introduction. Bleaching with hypochlorites. Bleaching with peroxides. Bleaching of wool with hydrogen peroxide. Bleaching of silk with hydrogen peroxide. Bleaching of synthetic fibres with peroxide. Advantages and disadvantages of peroxide over hypochlorite bleaching. Bleaching with sodium chlorite. Bleaching with peracetic acid. Reductive bleaching of wool. Bleaching of silk with reducing agents. Reductive bleaching of nylon. Peroxygen bleaching compounds. Bleaching of jute. Bleaching of linen. Bleaching of blended fabrics. Bleaching of cotton weft knitted fabrics. References. Bleaching and Washing Equipment. Introduction. Batch bleaching process machineries. Semi-continuous bleaching process machineries. Continuous bleaching by J-Box systems. Continuous open-width bleaching equipment. Washing equipment. References. Heat-Setting. Introduction. Thermal behaviour of synthetic fibres. Stages of heat-setting. Methods of heat-setting. Heat-setting conditions for different kinds of fibres. Heat-setting of blended fibre fabrics. Effect of heat-setting on properties of synthetic fibres. References. Mercerization. Introduction. Conditions for mercerization. Changes in properties of cellulose on mercerization. Mercerization of remie and flax fibres. Mercerization of blended fibre fabrics. Mercerizing machineries. Hot mercerization. Liquid ammonia mercerization. References. Optical Brightening Agents. Introduction. Chemical constitution of optical brighteners. Mechanism of fluorescent whitening. Factors influencing the functions of optical whiteners. Application of optical brighteners. References. Combined Pre-Treatment Processes of Textiles. Introduction. Combined scouring and desizing. Combined scouring and bleaching. Combined desizing, scouring and bleaching. References. Degradation of Fibres Associated with Chemical Pre-Treatment Processes. Introduction. Degradation of cotton during desizing. Degradation of cotton during scouring. Degradation of cotton during bleaching. Damage of wool during pre-treatment processes. Damage of silk during pre-treatment processes. Damage of polyester during pre-treatment processes. References. Conservation of Energy and Water, Economy and Effluent Control in Pre-Treatment Processes. Water consumption in textile industry. Impurities in water. Water purification. Economy through energy conservation. Economy through water conservation. Economy through process modification. Pollution aspects in pre-treatment processes of textiles. Pollution load and pre-treatment processes. Waste water treatment from pre-treatment plants. Protective measures for ultra-violet radiation. References. Pre-Treatment of Textiles under Plasma Conditions. Introduction. The concept of plasma. Generation of plasma and its action. Surface modification of fabrics under plasma treatment. High energy radiation of textiles. References. Application of Bio-technology in the Pre-Treatment Processes of Textiles. Introduction. Enzymes for textile application. Treatment of cotton with enzymes. Treatment of protein fibres with enzyme. Bio-technology and effluent treatment. References. Analysis and Testing in Preparatory Processes. Introduction. Analysis of water. Analysis of non-cellulosic residues. Evaluation of wax content in cotton. Evaluation of lubricants. Determination of moisture content. Tests and analyses of sizes. Determination of the efficiency of scouring. Testing and evaluation of bleaching agents. Assessment of damage of cellulose. Assessment of damage of wool. Determination of degree of mercerization. Evaluation of whitening efficiency of optical brighteners. Determination of degree of heat-setting. Determination of biodegradability of surfactants. References. Subject index.