2. Yarns

Question 1

Yarn

Answer 1

A fine, continuous length of fibres with or without twist

Question 2

More twists =

Answer 2

Stronger but less light reflecting

Question 3

Thickness of yarn and yarn twists…

Answer 3

Weight, flexibility, handle, and end-use of the fabric

Question 4

Examples of staple yarns

Answer 4

Cotton, linen, hair, wool, spun silk, or cut manufactured fibres

Question 5

Examples of filament yarns

Answer 5

Continuous filaments of silk and manufactured fibres

Question 6

Z twists

Answer 6

Clockwise

Question 7

S twists

Answer 7

Anti clockwise

Question 8

Carding

Answer 8

Brushing to remove dirt and lanolin, causes fibres to lie parallel

Question 9

Reasons for ply yarns

Answer 9

Increases strength, regularity, texture, and weight, and creates a special effect

Question 10

Combing

Answer 10

Improves strength of the yarn, regulates the thickness, and increases the lustre

Question 11

Wet spinning method

Answer 11

Polymer
Spinneret
Into chemical fluid
Solidified

Question 12

Dry spinning method

Answer 12

Polymer
Spinneret
Into stream of warm air
Evaporates the solvent
Solidifies

Question 13

Melt spinning method

Answer 13

Polymer
Spinneret
Into stream of cold air
Cools and solidifies

Question 14

What affects the smoothness of a yarn?

Answer 14

Spun yarns are hairy due to the staple yarns used

Filament yarns are smooth

Question 15

What affects the handle of a yarn?

Answer 15

A smooth filament yarn helps make the fabric feel compact, a hairy yarn gives a fuller handle

Question 16

What affects a yarns lustre?

Answer 16

Filament yarns are smooth so more light reflects off them

Question 17

What affects regularity of a yarn?

Answer 17

Impossible to achieve the regularity in the thickness when spinning a yarn, staple fibres make irregular yarns because are different lengths

Question 18

Thermoplastic

Answer 18

Can be softened by heat, hardened by cooling, and then softened by heat over and over again

Question 19

If a yarn is coiled how does it affect the properties?

Answer 19

Gives it elasticity as the coils stretch out

Question 20

If a yearn is scrunched up how does it affect the properties?

Answer 20

Soft because fibres sticking out

Question 21

How can yarns be bulked

Answer 21

Putting air into it by finishing e.g. False twist, BCF, air-jet texturing

Question 22

Why bulk yarns?

Answer 22

Makes it softer

Question 23

Examples of fancy yarns

Answer 23

Boucle, ratings, stub yarn, chenille yarn, loop yarn (towelling)

Question 24

Chenille

Answer 24

Cut pile/nap bound to a core

Question 25

Example of core spun yarn

Answer 25

Elastic because Lycra can’t be by themselves

Boucle