Lesson: 9
Subject: Clothing and Textile
Unit:
Grade: 9
Topic: Fibers
Time: Two 90 minutes sessions
Objectives: At the end of the lesson student should be able to:
1.Tell what are fibres
2. Name Fibres of fibres
3. Classify fibres using burning test
4> Write some of the characteristics of named fibres
Concepts:
It is important to know about fibres so as to make the right choice when constructing an item and also to ensure proper laundering
Skills: Classifying fibers experiment and recording findings
Focus Question:
You plan to make a table runner for your mother , What is the best fabrics you would use?
Explain why , supporting your choice with your knowledge of the characteristics of the fibre
That makes up the fabric
Teaching Method: Experimenting, research, discussion Questioning,
Instructional Aid: Bunsen burner , fibers of various types , report sheet
Reference: Text ,Home Economic in Action , other supporting texts
Content Outline:
!. -Fibres are classified according to the source from which they come
-Natural fibres come from natural sources which maybe animals or plants
Manmade fibres come from are are manufactured fibres
2.Plant fibres are fibres that come from plants they are reffered to vegetable or cellulose
Because the are composed from woody vegetable substances called cellulose.
fibres from plants include cotton from the cotton plant, flax from the flax plant, hemp from hemp stem., sisal from the leaves of the agrave plant, coir from coconut husk, jute, from the jute plant, pina, from pineapple leaves.
Fibres From Animals sources are also called protein fibres, these include silk from the cocoon of the silk worm, wool from sheep, hair fibres such as mohair. The best quality hair fibre comes from the Merino sheep.
Mineral Fibres these include asbestos which comes from rock. It is however no longer recommended for clothing, metallic fibres which are made from metals. glass fibres.
Man made fibres are also called synthetics are manufactured with the use of chemical. They may be made from only chemicals substances or mixed with natural substances. To produced what is called regenerated fibres. E.g. glass is manufactured from sand but the fibre is restricted only to household articles and furnishing.
Some others are Nylon viscose, acetate triacetate, polyester, acrylic ,and modacrylic.
Identifying of Fibres: this is done in several ways
1. Visual inspection this is the first step and is not a very accurate method as many manmade fibres are made to look like natural fibres.
2. Length of Fibres are made from staple fibres but some can be twisted into filament fibres
If a yarn is untwisted you will see the length of, cotton, wool ,length of the staple fibres
3. Sheen lusture or lack of lusture can be easily determined by sight and touch.
4. Texture the weight and texture of fibres can be identified by sight and toucg you can feel if the fabric is soft m coarse, soft, smooth, stiff or flexible.
5. Burning test this is used to identify the chemical composition of a fibre. The way the fibre behaves when a flamed and the results after burning will give an ideaof its origin whether it is natural or man made
Fibers and the burning test | |||
| Fibres Cotton Linen Silk (pure wool nylon polyester acrylic Viscose rayon | Flame reaction burn quickly, with yellow flamme burns slower than cotton yellow ,flame burns melts slowly,sputters small slow flickersm sizzles and curl melts and burns quickly burns slowly, melts flame rappidly splutters and melts burns quickly, | Odor burning paper burning paper burning hair or feather smells like hair,or feather small like celery like burning meat slightly sweetish like burning meat | Residue Light feathering grey ash black if cottonis mercised ash feathery grey ask round crisp shinny black beads crushes easily crisp dark ash irregular shape shape crushes easily round hard , tough grey beads round hard brittle;black beads light grey feathery ash |
-Teacher brings scrap book of sample of fabric to class allow student to observe and touch them.
-Revision of natural fibres done in grade seven .Class discussion on how to obtain these fibres
-Teacher allows students to carry out burning test and record findings.
-Students will be give names of fabric to research their characteristics apart from what they found from the burning test.
Student will be asked to complete table below explain the fabrics they would choose to make a particular article
Example
article natural manmade Reason of choice Name of fabric
Kitchen towel √ Absorbs water, cheap cotton
Table cloth √ Crisp heavy linen
curtain √ Crease resistant
Dries easily polyester
-Making the 48 game fibre cards
Play game matching fibres to properties
Complete the table | ||||
article Kitchen towel table cloth curtains | natural √ √ - | man made - - √ | reason absorbs water,cheap crisp, heavy crease resistant | fabric cotton linen polyester |
Evaluation:
Answering question on lesson by filling in the missing letters in related words, and completing sentences.
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