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Technology

Grade 7

Processing: textiles

Module 17

The textile industry

  1. The history of the textile industry

The textile industry came into existence when people discovered that the cover of hair from some animals (e.g. the sheep) could be used without slaughtering the animal. A method for using these fibres was then developed, through spinning them together to make yarn. The fibrous nature of some plants, like the flax plant, also made it possible to spin threads which could be woven into fabric.

Today, most fabrics are knitted or woven. Fibres that are used may be natural and may be obtained from plants or animals.

Fibres may also be synthetic (produced artificially). Such textiles are produced from minerals like coal and petroleum. Examples of artificial fibres are nylon, acrylic and polyester fibres. Sometimes artificial fibres are combined with natural fibres. In this way we, for example, obtain polyester cotton.

See how many garment labels that indicate that polyester-cotton was used for the manufacture of the fabric you can find.

  1. Qualities of fibres

The length, density, strength, fineness and elasticity, as well as resistance to chemicals and moisture, determine the quality of the textile that is manufactured from a fibre. In this way, the qualities of the different types of fibres will determine the qualities of the fabrics that are made from them. The way in which fibres are knitted or woven also plays a role.

That is why a garment should have a label to describe the textile from which it is made, as well as give guidelines about how the garment should be taken care of or washed.

Study the following examples of such labels and talk about them in your groups:

  1. Doing research on the different clothing fabrics

Assignment 1:

[lo 1.1]

  • Study the labels from 3 garments and complete the table that follows:
Garment Description of textile Washing instructions Texture of fabric Fabric mass Elasticity of fabric
E.g.: T-shirt 100% cotton Cold wash hand wash Soft Light Not much

Because different types of fabric have different qualities, people choose different types of textiles for specific purposes. Soft fabrics are usually selected for garments that will be worn against the body, while other fabrics are needed for warm jerseys and jackets.

  • The following table presents a summary of the qualities of different types of fibres and also indicates how articles made from these fibres should be taken care of.
Fibre Qualities Care
Cotton CoolCan absorb moistureLittle elasticityCreases easilyVery flammableSoft/coarse, depending on weave Machine or hand wash / LukewarmRinse thoroughlyHang up to dry or spin dry. Coloured cotton is faded by the sunIron with warm ironWhites may be bleached
Wool Keeps in warmthElasticWeak when wetCan shrink Does not crease easily Dry clean / Hand washDry in shade / Lay down flatAvoid ironing, or cool iron
Artificial fibres StrongDo not absorb moistureDry easilyCrease resistantDo nor shrink or stretch (Lycra is an exception)Melts at high temperatures Warm wash- machine or handHang up or spin dryDoes not need ironing
  • Make use of the information you have gathered to select a suitable fabric for:
  • a school shirt
  • a winter jacket
  • long trousers for a boy
  • Fabric qualities:

Follow the instructions and draw up a table to record your observations.

  1. Durability :

Choose three different types of fabric. You need to be reasonably sure that you know what fibres were used during the manufacturing process.

  • Stretch the fabric over the open end of a tin and secure it in position with an elastic band.
  • Rub a stone against the fabric, using even movements until a hole is formed.
  • Compare the strength of the different fibres.
  • Flammability :

Take the same pieces of fabric and hold them close to a flame. What do you observe?

  1. Absorption of moisture :

Place the fabrics in water to see which one absorbs water most easily.

Place the wet fabric outside to see which one dries the fastest.

Fabric 1. 2. 3.
Fibres
Durability
Flammability
Absorption of moisture

Assessment

LO 2
TECHNOLOGICAL KNOWLEDGE AND UNDERSTANDINGThe learner will be able to understand and apply relevant technological knowledge ethically and responsibly.
Assessment Standards(ASs)
We know this when the learner:
Structures :2.1 demonstrates knowledge and understanding of structures.

Questions & Answers

what is phylogeny
Odigie Reply
evolutionary history and relationship of an organism or group of organisms
AI-Robot
ok
Deng
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Hajah Reply
the study of living organisms and their interactions with one another and their environments
AI-Robot
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HOW CAN MAN ORGAN FUNCTION
Alfred Reply
the diagram of the digestive system
Assiatu Reply
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Ogenrwot
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William Reply
They formed in two ways first when one sperm and one egg are splited by mitosis or two sperm and two eggs join together
Oluwatobi
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Josephine Reply
Genetics is the study of heredity
Misack
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Misack
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Hassan Reply
discuss biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles
Joseph Reply
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Yousuf Reply
the study of living organisms and their interactions with one another and their environment.
Wine
discuss the biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles in an essay form
Joseph Reply
what is the blood cells
Shaker Reply
list any five characteristics of the blood cells
Shaker
lack electricity and its more savely than electronic microscope because its naturally by using of light
Abdullahi Reply
advantage of electronic microscope is easily and clearly while disadvantage is dangerous because its electronic. advantage of light microscope is savely and naturally by sun while disadvantage is not easily,means its not sharp and not clear
Abdullahi
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Abdullahi
is like gone fail us
DENG
cells is the basic structure and functions of all living things
Ramadan
What is classification
ISCONT Reply
is organisms that are similar into groups called tara
Yamosa
in what situation (s) would be the use of a scanning electron microscope be ideal and why?
Kenna Reply
A scanning electron microscope (SEM) is ideal for situations requiring high-resolution imaging of surfaces. It is commonly used in materials science, biology, and geology to examine the topography and composition of samples at a nanoscale level. SEM is particularly useful for studying fine details,
Hilary
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Source:  OpenStax, Technology grade 7. OpenStax CNX. Sep 10, 2009 Download for free at http://cnx.org/content/col11032/1.1
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