Dr Ambedkar Government Arts College , Vyasarpadi, Chennai - 39

I B.Sc - Home Science - Nutrition , Food Service Management and Dietetics 2020-2021 (UG)

SEMESTER –V

Subject Code: Credits - Elective Course -I

ELECTIVE PAPER I-FUNDAMENTALS OF

Unit I : TEXTILES FIBRES

Classification, general properties, use and care of the following fibres

a. Cellulose fibres – and .

b. Protein fibres – and .

c. Thermoplastic fibres - and

Unit II: CONSTRUCTION

a. Yarn spinning – Mechanical and chemical, conventional and non- conventional, wet, dry and melt spinning.

b. - Classification based on numbering and twisting.

c. Types of yarns- Simple, Complex or novelty and textured yarns

Unit III: FABRIC CONSTRUCTION

a. -Parts of simple loon and weaving steps.

b. Types of weaves- Basic weaves and their variations – , Dobby and Jacquard Felting and braiding.

Unit IV: FABRIC

a. Basic finishes- Bleaching, tentering, singeing, sizing, mercerizing

b. Special finishes- Calendaring, napping, flocking, water repellency, sanforising, wrinkle resistance and fire retardant.

Unit V: SURFACE DESIGNING

a. Dyes- Classification and different methods of .

b. Methods of printing- Hand printing- Block, Stencil, , tie and dye

Machine printing- Roller printing, screen printing REFERENCES

Corbman B.P., 1987, Textiles- Fibre to Fabric. New York, Mc Graw Hill Book Co.

1. Dorothyseigeithyle., 1976, Modern Textiles. New York, London, John Wiley and sonslnc.

2. Hollen. N and Saddler. J., 1977. Textiles. New York, Mac Millan.

3. Mathews. M. 1974. Practical clothing construction- Part I and II. Thompson and Co Ltd.

4. Tortora P.C. 1976, Understanding Textiles, Mac Millan, London.

5. Vidyasagar. P.V. 1998. Hand Book of Textiles. New Delhi, Mittal Publications,

6. Wingate. I. 1976. Fibres and their selection. Prentice Hall.

Dr Ambedkar Government Arts College , Vyasarpadi, Chennai - 39

I B.Sc - Home Science - Nutrition , Food Service Management and Dietetics (UG)

2020-2021 Major paper

FOOD PRESERVATION AND PROCESSING

Unit —1

Napping

It is a mechanical finish in which fibres are raised from the woven or knitted fabrics by rotating, bristled and wire covered brushes. The fabric brings out raised fibres all through its surface. The examples of napped fabrics are cotton , rayon flannel, woollen and worsted napped fabric like kersey and melton. Napped fabrics have softer handle, better insulation properties due to more air entrapment. These fabrics are mainly used as blankets and for winter clothing.

Braiding

Braids are narrow fabrics in which yarns are interlaced lengthwise and diagonally. They have good elongation characteristics and very pliable curving around edges. They are used for shoe layers, coverings, components in technical products such as wiring and housed for gasoline and water. Braid is stretchy and easily shaped.

Felting

In olden days is made by wool. Spreading out the wet wool and beating until it takes shape into a fabric like form. in modern factory, layers of wool are build up until the thickness is attained and then heat, soap and vibration are used to mat the fabric together. It is used for padding, sound proofing, insulation, filtering, polishing, wicking, mat, slippers applied designs. • It has no seam finishes • It has no grain • It has poor pliability, stretch recovery • It is used in apparel accessories, craft and technical matting.

Flocking

It is an finishing process that produces pile appearance. This method of creating a raised surface is different from that of napping, digging, sueding. A flock surface is created by first applying adhesive the desired pattern after which flocking can be done either by mechanical or electrostatic methods. Flocked fabrics are used for products such as T-Shirts, wall papers, jewellery, boxes or upholstery. Flocked surfaces reduces water condensation, acts as a good thermal insulators. It is also used in automobile industry for glove compartment boxes, door mouldings and window trim. Dobby Weave

Dobby weave is a patterned weave used to construct designs that cannot be produced by the plain, or weaves.

Dobby fabrics have small figures, such as dots, Geometric designs and small floral patterns, woven into the fabric. These decorative weaves are made with small patterns that repeat frequently.

Yarn spinning process

Yarn spinning is a process of making or converting materials into yarns. [1] Since few centuries ago, spinning have been known as a process of converting raw materials(fiber) such as cotton and wool into yarns for making textile fabric or products. There are two classes of spinning process chemical Spinning and Machine Spinning.

Chemical spinning

Introduction:

A filament fiber is the fiber which comes in continuous lengths for use. All the man-made fibres and silk is filament in nature. The man-made can also be cut into staple length and spun on usual spinning system for the spun yarn production. The filaments are spun by chemical spinning which includes the process of extruding the polymer extrusion through the spinneret. These filaments are solidified in fiber form. These solidified filaments are brought together and are slightly twisted to produce filament yarns.The different types of chemical spinning are as follows: 1. Wet spinning

2. Dry spinning

3. Melt spinning

Chemical Spinning 1. Wet Spinning: This method of spinning is more suitable for rayon fibers. The procedure of spinning involves the extrusion of an appropriate liquid solution through the spinneret in a chemical bath that coagulates the solution into filament strands. These filament strands are then drawn out of the bath, washed and dried before being wound on the spools. The fibers are spun in the chemical bath and hence called as wet spinning.

2. Dry Spinning:

The process involves the extrusion of the suitable liquid solution through the spinneret into an air chamber. The air reacts with the extruded streams causing them to solidify twisted and/or processed further and then wound onto spools. This method of spinning is used in manufacturing of acetate yarns.

Fig: Principle of dry spinning 3. Melt Spinning:

Melt spinning uses the heat to melt the polymer to a viscosity suitable for the extrusion through the spinneret. As the name indicates the chips of fibers are melted and extruded through the spinneret to obtain the fibers. It is used for the polymers that are not decomposed or degraded by temperatures necessary for extrusion. Polymer chips obtained from previously reacted chemical combinations are melted and then pumped through a spinneret in an air chamber. The extruded stream cool and solidify into continuous filaments and are then drawn out of the chamber twisted and/or processed further and subsequently wound onto spools. This method of spinning is suitable in manufacturing the polyester yarns.