Wool and Mohair Flashcards
Define wool
hair from a sheep
Define mohair
fleece of an Angora goat
Which countries lead in wool production?
China and Australia
Which countries lead in mohair production?
South Africa and Texas (U.S.)
What is a primary hair follicle?
Primary hair follicles are larger in size, are the first follicles to develop, are arranged in groups of three, and are fully emerged at birth.
All accessory structures are present (arrector muscle, sebaceous glands, sweat glands).
They appear in bundles with secondary fibers.
What are secondary follicles?
Secondary follicles are smaller in size. They are associated with the primary follicles. They normally emerge between 1 and 3 weeks of age.
Secondary follicles have an incomplete set of accessory structures (they lack arrector muscles and sweat glands).
What factors affect follicle development?
- Adverse prenatal environment
- early postnatal environment
both can limit fiber growth
What fibers do consumers prefer and why?
They prefer the fibers from secondary follicles because they are more fine.
What is the cuticle?
The scaly outer layer that is present in all wool fibers.
What is the cortex?
The cortex are the needle like cells present in the wool fiber. It determines the crimp (waves in wool fiber).
What does ortho mean and what does it relate to?
Ortho- soft, elastic
relates to the cortex
What does para mean and what does it relate to?
para- hard, less elastic
relates to the cortex
What is the medulla?
Medulla are the hollow air spaces in the wool fiber. They are absent from finer wools.
What are kemp?
Kemp are larger fibers without a solid core, they have lots of medulla.
What do arrector muscles do?
Make hairs stand up on end
Define fleece
wool from a single sheep
define clip
amount of wool from a flock of sheep
What is the primary constituent of wool?
Keratin is wool’s primary constituent. It is a protein that serves as the building block of the wool fiber.
Describe the chemical composition and arrangement of keratin.
Keratin is composed of long, flexible polypeptides with sulfur containing amino acids like methionine and cysteine.
Sulfide bonds hold the polypeptide bonds together in a helical arrangement.
What factors affect the amount of wool produced?
Nutrition: sheep need adequate protein and energy for wool production
Breeding program: yield has a genetic component
What are the selection criteria for wool?
- Fleece weight
- Fitness of hair
- Length of fibers
What are the impurity types in wool?
- Natural
- Acquired
- Applied
What are natural impurities in wool?
Natural impurities are produced by sheep themselves. Some types are listed below.
- grease - produced by the sebaceous glands
- suint - produced by the sweat glands
Grease + suint = yolk
What is grease wool?
Grease wool is wool before natural impurities are removed.
What is lanolin?
Lanolin is refined wool grease. It is used in moisturizers, makeup, etc.
What are acquired wool impurities?
Acquired impurities are picked up by the sheep. They include things like dust, dirt, sand, manure, urine, etc.
What are applied wool impurities?
These are impurities applied by people such as sprays, dips, dyes, etc.
What is scouring?
Scouring is the use of a soapy solution to remove natural and applied impurities.
What is carbonizing?
Carbonizing is the use of acid to remove organic matter from wool.
What are Merino sheep?
Sheep known for their fine wool
What is shrinkage in regard to wool?
wool weight lost due to impurities
What is wool yield?
wool weight remaining after cleaning (scouring)
yield - shrinkage = ?
loss of weight due to impurities
How is wool graded?
The main criteria is fiber diameter.
What is the American (blood) grade for wool?
This grade is based upon how much Merino blood is in the sheep.
ex. 1/2 blood, 1/4 blood
What is the spinning count?
hanks (560 yds.) of yarn per pound of clean wool
What is micron diameter?
The actual fiber measurements, and the most accurate way to grade sheep wool.
Describe wool length.
The staple length of fibers are a factor used in grading. Longer fibers are better for manufacturing.
What is noilage?
Short, unusable fibers
Describe wool color
White wool is preferred because it is easiest to dye
What are the preparations for wool spinning and weaving?
- Growing
- Shearing (mechanical or chemical)
- Grading
- Sorting
- Blending
- Scouring
- Carding (aligning the fibers to make them parallel)
What is woolen yarn/fabric?
Woolen is the type of fabric typical of sweaters. They trap air and stay warm due to their crossed patter (think a bunch of x’s).
What is worsted yarn/fabric?
Worsted fabric is typically found in pants, suits, and jackets. It has a parallel fiber design that removes the noilage.
What is felt and how is it made?
Felt is created by heating the wool fiber cuticle and matting them together.
What are some positive qualities of wool cloth?
warm, nonflammable, can absorb moisture, excellent insulator
What are some negative qualities of wool cloth?
It can shrink, and it itches some people.
What is woolmark?
Pure wool
What is woolmark blend and woolmark?
They are labels that assure quality.
