Knit fragments dating back to 250 BC
◦
Compared to 9,000 years for wovens
y
Introduced to Europe by the Arabs
◦
Did not gain popularity until around 1,000 AD
Chapter 9 Knitted Fabrics and
Their Properties
Knit fragments dating back to 250 BC
◦ Compared to 9,000 years for wovens
Introduced to Europe by the Arabs
◦ Did not gain popularity until around 1,000 AD
Knitting
The act of interlooping yarn to create fabric as opposed
to weaving, which is interlacing yarns to create fabric.
Loop Components
Loop Appearance
Knitting Industry
Two main segments
◦ Knitted yard goods
◦ Knitted apparel
Advances in computer technology
◦ Ability to respond quickly to the rapidly
changing fashion industry
Knitting Machines
Two basic types of knitting machines
◦ Flat knitting machines – Fig. 9-2 p. 140
Produce flat fabric
Produce both warp and
weft knits
Knitting Machines
◦ Circular knitting machines – Fig. 9-3
Predominately weft knits
Produce tubular fabric
Faster than flat knitting machines
Knit v.Woven
KNITS (slide 1)
◦ Cheaper to produce
◦ Require higher quality yarns
◦ Yarns must be uniform so that thin spots don’t form
on the fabric
◦ Looped structure =
Knit fabric is less opaque
provides less cover
Allows for stretch + recovery as body moves
Requires thicker and/or heavier yarn to provide
equal cover to that of a woven
Tendency to snag /run in weft knits
Knit v.Woven
KNITS (slide 2)
◦ Easier / quicker to change design patterns
◦ Known for comfort and ease of fit
◦ Bulky = good insulation and warmer
◦ Wrinkle recovery superior
◦ Problem with stretching out
Should be folded not hung
Sagging at stress points (knees, elbows)
◦ Shrink more than wovens
Knit v.Woven
WOVEN
◦ More expensive to produce
◦ Can use lower-quality yarns
◦ More difficult to change pattern on loom
◦ Looms use more energy/louder than knitting machines
◦ More rigid/less able to conform to body
◦ Superior resistance to wind
◦ Can be set with sharper pleats and creases
◦ Do not stretch out/can be hung
◦ Less tendency to hang
◦ Less tendency to shrink than knits
Knitting Terminology
Stitch
◦ The loop of yarn formed by the knitting process
Knit
◦ Basic knitting stitch
Purl
◦ Horizontal rows
Wales
◦ Loops formVertical ribs/columns – parallel to selvage
Gage or Gauge
◦ the density of knitting machine needles, and the
number of knitting needles per inch (approx. 2.54cm).
The smaller the figure, the coarser the stitch, and vice
versa
Knitting Terminology
Courses
◦ A series of successive loops laying crosswise in the
fabric
Face/Back
◦ Just like a woven fabric, there is a face and a back to
the knitted fabric
Cut
◦ The fineness of weft knits made on a circular knitting
machine
The higher the gauge or cut number, the finer the fabric
Variables in Knitted Construction
A great deal of variety may be created by
manipulating the following:
◦ Fiber content
◦ Yarn type and twist
◦ Fabric count
◦ Coloration
◦ Finishes
Weft Knits
◦ Can be made by hand knitting, or a circular or
flat bed machine
◦ Made with one continuous yarn that travels
around the fabric on a circular knitting
machine and across the fabric on a flatbed
machine.
◦ Common weft knits:
jersey knits
rib knits,
purl knits
Wales on front – vertical
Courses on back - horizontal
Weft Knit StitchVariations
Miss or Float Stitch
◦ Used to create patterns or change colors
◦ Reduce the stretch of the fabric
◦ Prone to snagging
Tuck Stitch
◦ Used to create pattern and textured effects
◦ Identified by open lacy areas, bubbles, puckers
◦ Reduce the stretch of the fabric
Open,Transfer or Spread Stitch
◦ Fashion marks
Shaped to fit during the knitting process
Weft Knit StitchVariations
Open,Transfer or Spread Stitch
◦ Create texture
◦ Fashion marks
Occur when transfer stitches change the number
and position of the yarns
Shaped to fit during the knitting process
◦ Mock-fashion marks
Do not shape the garment
CommonWeft Knits
Jersey knits
◦ Also called single knits
◦ Economical to produce
◦ Knit stitches on front/ Purl stitches on back
Rib knits
◦ Knit and purl wales alternate across width
Purl knits
◦ Alternate courses of knit and purl stitches on
both sides of the fabric
Characteristics of Jersey Knits
Stretch crosswise and lengthwise
◦ Stretches more in the crosswise
Tend to run or ladder if stitch breaks
Produced under tension
◦ Fabric less stable and curls when cut
Special finishes
◦ Counteract curling and improve stability
End Uses of Jersey Knits
Sheets
Sweaters
T-shirts
Men’s underwear
Dresses
Hosiery
Characteristics of Rib Knits
Swatch #100
Reversible
More elastic than jersey knits
More stretch crosswise than lengthwise
Edges do not curl
Running and laddering still a problem
More expensive to produce
Rib KnitVariations
Double knits #104 & #105
◦ Sometimes called double jerseys
◦ Thicker than jersey knits
◦ Two-way stretch
◦ Very stable – will not ladder
◦ Apparel and Upholstery used
Interlock knits #103
◦ Specialized 1x1 rib knit
◦ More stable and smoother than regular rib knits
◦ Will ladder
◦ Underwear, blouses and dresses
Purl Knits
Produced on links and links machines
◦ Slowest of the knitting machines
◦ More expensive
Good stretch in all direction
◦ Stretches out of shape easily
Crosswise stretch less than a jersey knit
Thicker than jersey knits
Does not curl
End Uses for Purl Knits
Infant and children’s wear
Sweaters
Scarves
Warp Knits – see Fig. 9-8
Second major category of knit fabrics
Characterized by vertical loops
More resistant to laddering than weft
knits
Usually done on flat knitting machine
◦ Two main types of warp knitting machine
(name = machine and fabric name)
Tricot #106
Raschel #107
Minor warp knit – Simplex
Characteristics of Tricot Knits
Good elasticity
Best of warp knits
Inexpensive and quick to produce
Curls along crosswise edge
Good air and water permeability
Soft
Crease resistant
Good drapeability
End Uses for Tricot Knits
Lingerie
Nightwear
Blouses
Dresses
Used as a backing fabric in multi-
component structures
Limited interior uses because of high
elongation
Raschel Knits
Swatch #107
Similar to Tricot Knits
Greater diversity in design
Differences between Raschel and Tricot
Knits
◦ Raschel has:
More texture
Open spaces
Made from heavier yarns
Variations and End Uses of Raschel Knits
Warp knitted
Fine laces and nets
Heavy carpets
Thermal underwear with a waffle effect
Power-net fabrics for swimsuits and foundations
Heavy blankets
May resemble hand crocheted fabrics
Weft Insertion Knits
Insertion warp knits:
◦ Extra yarns may be inserted in the warp or in the
filling direction of warp yarns
InlayYarns:
◦ If yarns are inserted in warp direction
Power-net fabric:
◦ Raschel knit with inlaid spandex yarns.
Weft Insertion Characteristics
Fabric Appearance
◦ Extra set of yarns laid in
◦ Typically novelty yarns
◦ Other yarns may be laid in to add strength or stretch
Help add warmth or strength
Can be single or double knit
May also be warp knit
Care and Performance
Dimensional Stability = poor
◦ Stretch contributes to comfort but also to
poor dimensional stability
◦ Prone to shrinkage, stretching, and distortion
◦ Finishes
Shrinkage control
Heat setting of synthetics
Resin finishes
Air drying and dry cleaning and help minimize
shrinkage
Pilling
Care and Performance
Pilling
◦ Made from fibers and yarns that are likely to
pill – wool and synthetic fibers
Snagging
◦ Looped structure of knit fabric increases the
possibility that snags occur
If yarn has not been broken it is possible to work
back into the fabric
Handling in garment construction
Pattern
◦ Seam allowances vary on patterns, the 1/4" (6 mm)
seam allowance is the easiest to use.
Layout
◦ Knits have shading and pattern pieces should be cut in
one direction and be placed with the greatest degree
of stretch around the body.
Marking and Cutting
◦ Use weights to hold pattern pieces in place.A rotary
cutter works very well with knits, just be sure to use
a matt to protect your cutting table.
Handling in garment construction
Lining
◦ Interfacing is used to reinforce closures, add shaping to collars,
cuffs and plackets and stabilize areas such as shoulder seams and
some necklines.The best interfacing is a 100% polyester fusible
lightweight knit interfacing.
Stitching
◦ Sew the seam using an overlock stitch.This stitch sews and
overcast in one step. It is not necessary to stretch the fabric
while sewing as stretch is built in.
Fasteners