YARNS AND SEWING YARNS AND SEWING THREADSTHREADS

- Chapter 4 -

Spider Silk tapestry: http://www.npr.org/templates/story/story.php?storyId=113223398&ft=1&f=1001

Tonight’s topics• Fibers spun into yarns

• Wide variety of yarns

• Yarn types affect fabric properties

• Unique size systems exist for yarns

• Different equipment is required to weave or knit with different yarns

• Fabric finish choices affected by yarn type

• Garment designs influenced by yarn types

• Sewing threads similar to yarns

Spun Yarn Filament Yarn

SPUN YARNS

• Staple fibers twisted together

• Twisting creates stronger yarns

• Identify by untwisting yarn fibers; spun yarn pulls apart into individual short fibers

FILAMENT YARNS• Continuous filaments as they come from

spinnerette/cocoon– Little or low twist

• Smooth lustrous surface

– Tightly twisted filament yarns• Crepe-filament yarns

• Strength of yarn depends on individual fiber strength and number of filaments

Monofilament• Composed of one filament

Multifilament• Composed of many filaments

• Most filament yarns are multifilament– More flexible than single filament yarns of

same diameter

TAPE & NETWORK YARNS• Tape Yarns

– Inexpensive– Produced in sheet form; then slit into .1” strips

– Common for olefins and metallics

• Network Yarns– Air included in solution to make foam; air pockets pop

when fiber is drawn, creating a network of interlocked fibers– Industrial uses where bulk and low density are more

important than high strength

Carded And Combed Yarns(1 smoothing step) (2 or more smoothing steps)

• Fabrics of combed yarn look better, feel smoother, are stronger, and are more expensive than fabrics of carded yarn

• Fabrics of combed yarn retain shape better and pill less

• Fabrics of carded yarn are bulkier, softer, and fuzzier.

Linen Yarns

• Tow = short fibers = coarse texture = rough finish; homespuns

• Line = long fibers = smooth texture = fine finish; handkerchief linen

Wool Yarns

• Woolen– Made of carded yarns– Noils (snarls)– Fuzzy– Uneven diameter– Bulky– Wide range of fiber

lengths– Sizing called run and

written like this: 2/50

• Worsted– Made from combed yarns– Smooth with little fuzz– Even diameter– Tightly twisted– May shine– Firm– Size called worsted and

written like this: 2/50

Woolen

Yarn

Worsted Y

arn

http://www.youtube.com/watch?v=qUEDWjd9cLk

Spinning Methods Ring (Conventional) Method

• Opening– Loosens the bale, blends and cleans fibers, forms lap

• Carding– Cleans and aligns fibers, forms carded sliver

• Drawing– Makes parallel and blends fibers, forms drawn sliver– May create fiber blends now

• Combing– Makes parallel and removes short fibers (noils), forms combed

(top) sliver (used only for long-staple cotton or worsted)

• Roving– Reduces size, inserts slight twist, forms roving

• Spinning– Reduces size, twists, winds the finished yarn on bobbins

• Winding– Rewinds yarns from bobbins to spools or cones

www.frontierspinning.com/locations/photo_tour/tour01.shtml

Other Spinning MethodsOpen-end Rotor Spun Method (O-E)

– eliminates some aligning steps

– 4x faster production than ring method

– coarser yarns with poorer uniformity and poorer strength

– commonly used for denim fabric

Air-jet Spun Method– coarser, weaker, and less elastic

– better cover (bulk)

Vortex Spun Method2x faster than OE

20-30 x faster than ring spinning

Not as uniform as ring spun

BLEND = two or more fibers mixed in one yarn – intimate blends– combines good and bad properties of fibers– spun blends most popular; filament blends available

COMBINATION = ply yarns; each ply is 1 generic type of yarn– Metallics; fasciated yarns

MIXTURE = yarns of different generic types used within a fabric (warp is 1 type, weft is another)

YARN TWIST• Turns per inch = tpi

– Soft twist • Soft, fluffy yarns; napping twist; 2 - 12 tpi

– Average twist • most durable staple yarns; not used with filaments

– Hard twist • high or voile twist; smooth, firm and kinky yarns; 20 - 30 tpi

– Crepe twist• highest twist; lively yarns; require special treatment; 40-80 tpi

• Filament yarns - very low twist (1/2 - 1 tpi)

Effects of Twist on Yarn and Fabric

• Fineness• Contraction• Bending behavior• Absorbency• Covering power• Permeability• Softness or hardness

• Tensile strength• Extension and

recovery• Resistance to creases

and abrasion• Pilling behavior• Luster

Up to the

left

S twist

Left – Right Twist

Up to the

right

Z twist

ZS

Why is Yarn Plied?

• Introduce different fiber yarns

• Combine spun and filament yarns

• Improve strength of a singles

• Make thicker, smoother strand

• Make more stable yarn and fabric

• Add texture or novelty yarn but maintain strength

• Add color interest

Ply Yarns ….

• Are more expensive

• Require better quality fiber, more labor, special machinery

• Most fabrics are made of singles

Yarn Size Systems• Relationship between weight of yarns and certain

length of yarn

• Yarn sizes– Yarn-count systems (spun yarns)

• cotton, lea, run, worsted

– Denier system (filament yarns)• d = denier• dpf = denier per filament

– Tex system (mostly for thread)• Tex and d-tex

• Yarn Count System– Larger the size number,

finer the yarn • Sheer lawn = 70s to 100s• Calico = 30s to 40s

– Written as 50/2 (yarn count + number of plies)

• Denier System– Higher the denier, larger

the yarn• 1 d yarn: 9000 meters of

yarn weighs 1 gram• 2 d yarn: 9000 meters of

yarn weighs 2 grams– Sheer hosiery = 20 d– Luggage = 100 d

• Tex System

• Spun yarns = yarn count system

• Spun yarns may be plied • Size is expressed as 50/2 count

(or if woolen or worsted as 2/50)

(2 yarns are twisted together & each yarn size

is 50/1 count)

• An equivalent sized singles yarn would be size 25 count (50 divided by 2)

• Filament yarns = denier system

• Filament yarns are seldom plied but when they are, the size is expressed as two-ply 80 denier– a singles yarn of comparable size would be

160 d. (80 x 2)

• 300-10-1/2 Z means a 300 denier multifilament yarn with 10 filaments (each 30 d.) with a half turn per inch and a Z-twist. This is NOT a plied yarn.

SPECIAL YARN TYPES

• MicrodenierMicrodenier

• StretchStretch

• Novelty Novelty

• ChenilleChenille

• MetallicMetallic

MICRODENIER YARNSMICRODENIER YARNS

• Developed in late 1980s

• Finer filaments than silk (less than 1 denier)

• Extremely soft and drapable

• Expensive

STRETCH YARNSSTRETCH YARNSPOWER STRETCH

• Holding power is required

• Highly elastic yarns

• High recovery force

COMFORT STRETCH

• Designed to yield with body movement

• Low recovery force• Fabrics look the

same as nonstretch

Types of Stretch Yarns

1. Bare Elastic

2. Covered Elastic

3. Core-spun

4. Textured yarns

Grin-through

Unrecovered stretch

• Covered elastic

• Core spun

Texturized yarns are widely used as comfort stretch yarns.

False-twist method Stuffer box method

Knife-edge method Air-jet method

Gear crimping Knit-deknit method

• Thermoplastic fibers made texturizing possible.

Slack mercerized yarns

Yarns with texture vs. texturized yarns

NOVELTY YARNSNOVELTY YARNS

• Fancies

• Yarns not uniform in thickness - seed - spiral or corkscrew

- nub - slub

- thick and thin - boucle

CHENILLE YARNSCHENILLE YARNS

• Pile twisted between 2 core yarns

• Low abrasion resistance

• Prone to pilling and balding

METALLIC YARNSMETALLIC YARNS

• Flat, ribbon-like– Tape yarns– Metallics and olefins

• Supported by wrapping with filament yarns– combination yarns– Fasciated yarns

• Usually for decorative purposes

SEWING THREADS• Main fibers: cotton, nylon, polyester, rayon• Main yarn types:

– Spun– Filament– Core spun

• Always plied• Highly twisted• Often treated with special finishes or

lubricants

THREAD FINISHES• Mercerization

• Soft

• Glace

• Bonded

• Flame resistant and heat resistant for high speed sewing

• Lubricated

THREAD SELECTION FACTORS

• Type of materials to be stitched together

• Type of seaming used

• Product performance expected

• Method of cleaning