Showing posts with label Textile Fiber. Show all posts
Showing posts with label Textile Fiber. Show all posts

Saturday, September 23, 2017

Lyocell

September 23, 2017 Lyocell , Modal 0 Comments
Lyocell is a regenerated cellulosic fiber. It is a manmade fiber but it shows both the properties of natural fiber and synthetic fiber. It will be clear when you will read the following physical and chemical properties of Lyocell. It is also known as Rayon, Modal, ‘Art Silk’ or Artificial Silk according to their manufacturing process. Rayon is also commonly known as viscose rayon. Though, viscose is a process to produce rayon. Regenerated fiber manufacturing process upgraded time to time. Below you get a short review of the transition stage.
·         Rayon [Ray (Sun) + On (Cotton)] 1st gen. process. (or viscose process)
·         Modal [HWM Rayon] 2nd gen. process (High Wet Modulus Rayon)
·         Lyocell [its Lenzing AG’s brand name “Tencel”] 3rd gen. process.







Presently, lyocell has great demand on Textile Industry for its great properties. It is soft and firm like cotton. Lyocell more demanded to them who has sensitive skin. Now a day, lyocell produce from bamboo. If we know the properties of the viscose rayon then it will be helpful to follow the next process.
Physical Properties:
·         Tenacity: 2.4 – 3.2 gm/den
·         Density: 1.64 – 1.54 gm/cc
·         Elongation at break: 13%
·         Elasticity: Good
·         Moisture Regain (MR%): 11 – 13%
·         Melting point: This fiber becomes weak when it heated above 150oc.
·         Ability to protest friction: Less
·         Color: White
·         Light reflection ability: Good but ultra violet ray damages the fiber.
·         Lusture: light to bright

Chemical Properties:
Acids: Viscose rayon is damaged by strong acids but it is moderate with weak acids.
Base: Good resistance to weak alkalis but strong alkali is harmful for viscose rayon.
Effect of bleaching: Strong oxidizing agents damage the viscose rayon fiber.
Organic solvent: Viscose rayon fiber has enough ability to protest the action of organic solvents.
Protection ability against mildew: Not good and mildew damages the rayon fiber.
Protection ability against insects: Viscose rayon is affected by insects and they cause harm to the                                                               fiber.
Dyes: Viscose rayon could be dye with direct, vat and sulphur dyes.
By at No comments:
Labels: , , , ,

Sunday, September 17, 2017

FIBER

September 17, 2017 Textile Fiber , 1 Comments
FIBER
Fiber (from the Latin fibra) is natural or synthetic substance that is significantly longer than it’s width. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, for example carbon fiber and ultra-high-molecular-weight polyethylene. Synthetic fibers can often be produced very cheaply and in large amounts compared to natural fibers, but for clothing natural fibers can give some benefits, such as comfort, over their synthetic counterparts. Fibers are classified into two options as follows:

Sources of Fibers and their Classification
There are many different sources from which we can obtain Fibers and therefore, we classify them accordingly.

  • Fibers from Natural Sources: All the Fibers obtained from nature, i.e., plants or animals, are known as natural fibers e.g. cotton, wool, linen, silk, etc. Fibers obtained from plant source are called cellulosic fiber e.g., cotton and linen. The fibers that come from animal sources are also known as protein fibers, e.g., wool and silk.
  • Man-Made Fibers: The Fibers which are made in laboratories using chemicals are known as man-made Fibers and these are of following two types:
    1. Regenerated Fibers: These Fibers are made from extremely small cotton Fibers or any other Fiber source such as wood pulp, milk protein, etc. Chemicals are used to dissolve these and the solution is then converted into solid Fibers. Examples are rayon (cellulose out of viscose/acetate/triacetate) of different types, casein Fiber (from milk) and soya bean Fiber.
    2. Synthetic Fibers: These are made using various petrochemical products. Nylon, acrylic and polyester are all synthetic Fibers.

COMMON CHARACTERISTICS OF DIFFERENT FIBERS
  • Cotton: Cotton Fiber is the smallest of the entire textile Fibers. They are white, cream or light brown in color and fine and strong. These are absorbent, porous and cool and allow the body heat to go out. Hence, fabrics made out of it are used as summer wear as cotton wrinkles very easily. Fabrics made from cotton are strong, durable and easy to wash and are used to make towels, sheets, pillow covers, etc., that require frequent washing.
  • Flax: It is a ‘bast Fiber’ and fabric made from it is called linen. It is a staple fiber though its length (20-30 inches) is more than the other staple Fibers available. Linen fabric is shiny, smooth, durable and easy to wash. Like cotton, it wrinkles very easily, is cool, absorbent and is suitable for summer wear.
  • Jute: Like flax jute is also a bast Fiber. The Fibers are short and lusturous but weaker than flax. The Fibers are hairy and generally rough. It is used for making gunny bags and cords. As jute is a rough Fiber, so these days jute is mixed with other soft fibers for fabric construction. Also increasingly these days accessories like slippers and bags made out of Jute are in popular demand.
  • Wool: It is obtained from the fleece of domestic goats, sheep, rabbits, etc. The color of wool Fibers may vary from off-white to light cream. Fabrics made from wool are soft, smooth, absorbent and do not wrinkle easily. These do not allow the body heat to go out and act as insulators. This is why the fabric made out of these Fibers is used as winter wear. Wool is a weak Fiber and is easily affected by common washing soaps, powders and friction.
  • Silk: Silk is a natural, protein filament produced by silk worm. Fabrics made from silk are soft, fine, smooth, lustrous, warm and stronger than wool. It is called ‘Queen of the Fibers’ and is used for formal wear.
  • Rayon: It is a man-made filament Fiber which is lusturous, smooth, cool and absorbent but is weak in nature. It wrinkles very easily. Because of its close resemblance to silk, rayon is also called ‘artificial silk’ or ‘art silk.’ It is used as a summer wear. These Fibers are thermoplastic in nature i.e., they are heat sensitive and soften and melt on application of heat.
  • Synthetic Fibers: Synthetic Fibers are made from petroleum products. Nylon, polyester, acrylic, etc., are the examples of synthetic Fibers. Like rayon these are also thermoplastic Fibers. Since these Fibers catch fire easily and can stick to the body, they should not be worn while working in kitchen and near a flame. Synthetics do not wrinkle and can be made dull or shiny. They have good strength and are easy to wash and dry quickly. In other words, these fabrics are easy to care and maintain.


Identify yarns made from different Fibers by breaking test – Collect samples of fabrics made from different Fibers. Take out yarns from each of these and keep each one separately. One by one, hold each yarn in both the hands and break it. You will observe the following:
1. Cotton - breaks easily, has brush like tips and slightly curled Fibers.
2. Flax - stronger then cotton, needs more strength to break.
3. Jute - yarn breaks easily.
4. Wool - yarn stretches and breaks with a brush like tip.
6. Silk - yarn breaks with a jerk.
7. Rayon - yarn breaks easily and does not have brush like tip.
8. Synthetics - yarn stretches and does not break easily.
By at 1 comment:
Labels: