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Semester 1: B.Sc. Textile and Fashion Designing
Introduction of Textile Fibers - Classification, Physical and chemical properties, Cotton classification, Organic cotton, Flax properties, Wool grading, Silk varieties
Introduction of Textile Fibers
Classification of Textile Fibers
Textile fibers can be classified into three main categories: natural fibers, man-made fibers, and synthetic fibers. Natural fibers are derived from plants or animals, while man-made fibers are produced from chemical processes using natural or synthetic materials.
Physical Properties of Textile Fibers
Physical properties include fiber length, diameter, strength, elasticity, and moisture absorbency. These properties influence the functionality and comfort of fabrics made from these fibers.
Chemical Properties of Textile Fibers
Chemical properties refer to the fiber's resistance to degradation, reaction to acids and bases, and susceptibility to mildew and insects. These characteristics determine the fiber's durability and care requirements.
Cotton Classification
Cotton can be classified based on fiber length, color, and the cultivation method (conventional vs. organic). It is commonly categorized into upland cotton, Egyptian cotton, and Pima cotton, each with distinct characteristics and uses.
Organic Cotton
Organic cotton is grown without synthetic fertilizers or pesticides. It promotes environmentally friendly practices and is often sought for its sustainability and reduced environmental impact.
Flax Properties
Flax fibers, derived from the flax plant, are known for their strength, durability, and natural luster. They are highly absorbent and have a low elasticity, making them suitable for linen fabrics.
Wool Grading
Wool is graded based on fiber diameter, length, and crimp. Common grades include fine, medium, and coarse wool. Grading affects the quality, texture, and suitability for various textile applications.
Silk Varieties
Silk is classified into several types based on the source, such as Mulberry silk, Tussah silk, and Eri silk. Each variety has its unique texture, luster, and applications in textile production.
Filament Spinning System - Methods, Semi synthetic fibers, Viscose rayon process, Bamboo and Lyocell fibers
Filament Spinning System
Introduction to Filament Spinning
Filament spinning is a process to produce continuous filaments from polymer solutions. The process includes dissolving polymer, extruding it through a spinneret, and solidifying the filament. Various industrial methods exist.
Methods of Filament Spinning
Common methods include melt spinning, dry spinning, and wet spinning. Melt spinning involves extruding melted polymer which solidifies upon cooling. Dry spinning involves evaporating solvent from a polymer solution. Wet spinning requires the polymer to be precipitated from a solution.
Semi Synthetic Fibers
Semi-synthetic fibers are derived from natural sources but modified for improved properties. Examples include viscose rayon which is processed from cellulose sourced from wood pulp.
Viscose Rayon Process
Viscose rayon is produced by dissolving cellulose in sodium hydroxide to form alkali cellulose. This is then treated with carbon disulfide, resulting in viscose which is extruded through a spinneret into a coagulating bath to form viscose fibers.
Bamboo and Lyocell Fibers
Bamboo fibers are derived from the bamboo plant and can be processed mechanically or chemically. Lyocell, known as Tencel, is produced through an organic solvent process that dissolves cellulose fibers from wood pulp, offering a sustainable alternative.
Polymer Science - Types of polymers, Synthetic fibers, Properties, Drawing and texturization
Polymer Science
Types of Polymers
Polymers can be categorized into several types based on their origin and structure. Natural polymers include proteins and polysaccharides, while synthetic polymers like polyethylene and nylon are man-made. Additional classifications include thermoplastics, thermosets, elastomers, and co-polymers, each with unique properties and applications.
Synthetic Fibers
Synthetic fibers are created through chemical processes, primarily from petroleum-based products. Common types include polyester, nylon, and acrylic. These fibers have distinct advantages such as durability, resistance to moisture, and ease of dyeing, making them popular in textiles and fashion.
Properties of Polymers
The properties of polymers are influenced by their molecular structure, degree of polymerization, and additives. Key properties include tensile strength, elasticity, thermal stability, and resistance to chemicals. These characteristics determine their applications in various industries, including textiles, plastics, and pharmaceuticals.
Drawing and Texturization
Drawing involves the process of elongating fibers to enhance their strength and orientation. Texturization adds bulk and texture to fibers, improving their aesthetic appeal and functionality. Techniques such as air flow, mechanical crimping, and heat setting are employed to achieve desired effects in both synthetic and natural fibers.
Yarn Production Process - Classification, Staple spinning, Ginning, Carding, Drawing, Combing, Ring frame, Rotor spinning, Comparison of carded and combed yarn
Yarn Production Process
Yarn can be classified based on its fiber content, length, and method of production. Common classifications include staple yarn, filament yarn, and fancy yarn.
Staple Yarn: Made from short fibers and is spun together.
Filament Yarn: Made from long continuous fibers.
Fancy Yarn: Designed with unique textures and patterns.
A spinning process that involves twisting together short fiber lengths to form a continuous yarn.
Fiber preparation and cleaning.
Drafting to align fibers.
Twisting fibers to form yarn.
The process of separating cotton fibers from seeds.
Essential for producing quality cotton yarn.
A process that disentangles, cleans, and intermixes fibers to prepare them for spinning.
Creates a continuous web of fibers called carded sliver.
The stage in spinning where slivers are combined and elongated to improve yarn strength and uniformity.
Enhances fiber alignment.
Improves yarn quality.
An optional process that removes shorter fibers from the sliver, resulting in smoother and finer yarn.
Produces combed yarn, which is stronger and softer than carded yarn.
A traditional method of yarn spinning where fibers are drawn through a ring and twisted together.
Produces high-strength and high-quality yarn.
Widely used in the textile industry.
A modern yarn spinning technology that uses a rotor to twist fibers into yarn.
Increased production speed.
Lower cost.
Made from carded sliver, contains short fibers.
Rougher texture.
Less strength.
Made from combed sliver, contains longer and aligned fibers.
Smoother texture.
Higher strength.
Combed yarn is generally superior to carded yarn in terms of softness and strength.
Post Yarn Process - Cone winding, Doubling, Properties of yarns, Yarn numbering, Blended textiles and sewing threads
Post Yarn Process
Cone Winding
Cone winding is a process that converts yarn from a package form, such as a cheese or spool, into cone form for convenience in textile manufacturing. The machine used for this process unwinds the yarn from the initial package and rewinds it onto cones, ensuring even tension and minimizing yarn defects. Proper cone winding is critical to maintain the quality of the yarn and facilitate subsequent processes.
Doubling
Doubling is a technique used to increase the thickness and strength of yarn by twisting together multiple strands. This process enhances the properties of the resulting yarn, including its durability and texture. Doubling can be done in various ways, including simple doubling and ply yarn production, which affects the final appearance and performance of the fabric.
Properties of Yarns
Yarns possess various properties that are essential for their performance in textiles. Key properties include strength, elasticity, moisture absorption, and thermal insulation. The type of fiber, the spinning method, and post-spinning processes such as twisting and doubling can significantly influence these properties. Understanding yarn properties is crucial for selecting appropriate materials for specific applications.
Yarn Numbering
Yarn numbering systems, such as thetex system and denier system, are used to classify the thickness of yarns. A lower number indicates finer yarn, while a higher number represents thicker yarns. This numbering helps in determining the appropriate fabric construction and end-use applications in textiles, impacting factors like drape, texture, and weight.
Blended Textiles
Blended textiles are made from two or more different types of fibers, combined to take advantage of the individual properties of each fiber. Common blends include cotton-polyester and wool-acrylic combinations. Blending can improve the performance characteristics of the fabric, such as strength, moisture-wicking, and comfort, resulting in versatile end-products suitable for various applications.
Sewing Threads
Sewing threads are specialized yarns designed for stitching fabrics. They are manufactured to possess specific tensile strength, elasticity, and abrasion resistance, ensuring that seams remain intact under stress. The choice of sewing thread depends on the type of fabric, the sewing method, and the end-use of the finished product. Threads can be made from various fibers, including cotton, polyester, and nylon.
