fibres. two kinds natural fibres that come from nature- plants and animals (although they are...

Fibres

Two Kinds

Naturalfibres that come from nature- plants and animals (although they are usually cultivated)

Man-made (synthetic)fibres made from the result of a chemical process

2 categories of natural fibres : Plants & Animals

Planty Fibres:• cotton, • flax, • hemp • Ramieand,…

Animaly Fibres:• wool• silk

• cashmere• camel • angora • alpaca

and…

What do they include?Plant fibres• includes seed hairs, stem fibres, leaf fibres and husk fibres. Animal fibres• includes wool, hair & secretions (silk).

What if you set them on fire?• Planty fibres would smell like….• Animaly fibres would smell like…

• Why do we care?????

Planty fibresCotton - from the cotton plant’s seed pod (boll)

The most commonly used natural fibre.

Cotton has been used since prehistoric times. It clothed the people of ancient India, Egypt, &China- hundreds of years before the Christian era.

Cotton cont.• Cultivated in around 80 countries, • one of the world's most widely produced crops • fundamental to the economies of many developing countries,

particularly in West and Central Africa (10 million small farmers depend on the sector for their income).

Cotton under a microscope• Draw this in your notes.

• This fibre is flat and ribbon like.• How will this shape affect the fibre in a yarn or fabric?

Answer…

First cotton is harvested.

• Then most of the seeds are separated from the fibres by ginning (a mechanical process) and are sewn together in bales.

Text reference- p. 121-122• Use your text to define combing

• (Why would include the information that cotton was combed on a hang tag?)

• Then they are spun into threads and yarn and woven.

Planty FibresFlax (also known as linen)- the oldest cultivated fibre - the actual material is taken from the stalkof the plant

Planty FibresHemp

originally used for ropes

Ramiea strong linen like fibre

Animaly Fibres

Wool comes from fibers from animal coats: goats, rabbits, alpacas, llama...

But we most commonly think of:

Animaly FibresSheep • first domesticated 10 000 years ago. Sheep are shorn of their wool usually oncea year.

• Merino sheep produce up to 18 kg of greasy wool a year.

• After scouring to remove grease and dirt, wool is carded and combed, then spun into yarn for fabrics or knitted garments.

• The world's leading animal fibre, wool is produced in about 100 countries on half a million farms.

• Australia, • Argentina, • China, • the Islamic Republic of Iran, • New Zealand, Russia, • the United Kingdom and Uruguay.

Wool under a microscope• Draw in your notes• Why does wool felt easily? Answer…• Is wool fabric shiny? Answer…

Wool under a microscope• Why is wool fuzzy? Answer…• Why is wool warm? Answer…

Animaly Fibres• The only source of true cashmere is the kashmir goat -native to the

Himalayas.

• Cashmere is the fine undercoat hair is collected by either combing or shearing during the spring moulting season.

• Annual yield of underdown averages around 150 g per animal (compared to 18 kg of wool from merino sheep).

Other “wooly” fibres: Camel Angora Alpaca

Mohair

Animaly Fibres• Silk fibers from the cocoon of the silkworm

Silk produced by the silkworm,Fed on mulberry leaves, it produces liquid silk that hardens into filaments to form its cocoon.

Silk is murder:

The larva is then killed, and heat is used tosoften the hardened filaments so they canbe unwound. Single filaments are combinedwith a slight twist into one strand, a processknown as filature or "silk reeling".

Silk under a microscope• Do you think silk would be strong or weak?• Why is silk shiny?

Other natural fibres• There are a few others we have not discussed:• Asbestos• Glass (fibreglass)

THERE ARE 2 LENGTHS OF FIBRES:

• Staples

• Filament

• Use the textbook to define the terms

• Decide which natural fibre is the only naturally occurring filament fibre?

All man made Fibres start out as filaments

Which brings us to the topic of man-made fibres…..