Lyocell & spundex
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Transcript of Lyocell & spundex
LYOCELL AND
Roksana Akther
B.Sc. In Textile Eng.
9th Batch
ID No: BTE00905469
Port city International university
INTRODUCTION Lyocell (lyo from Greek: lyein = dissolve, cell from
cellulose)
Man made cellulosic fibres
Produced by regenerating cellulose into fibre form out of a
solution (solvent spinning) of cellulose in an organic
solvent
‘Organic solvent’ - mixture of organic chemicals and water
‘Solvent spinning’ means dissolving and spinning without
the formation of a derivative
Tencel is the brand name of Lyocell
RAW MATERIALS Cellulose • Most abundant natural resource on earth.
• It is obtained from wood pulp.
• Trees like Eucalyptus , bamboo and pine tree are used.
• Eucalyptus is primarily used to produce the Tencel fibre.
MANUFACTURING AND PROCESSING
Preparing Wood Pulp
• Hardwood trees are harvested and logs are
taken to mill.
• Wood is cut into small chip and fed into a
chemical digesters which removes lignin and
softens them into wet wood pulp.
• It is then washed with water, bleached and
dried into huge sheets of cellulose and rolled
onto spools.
Dissolving Cellulose
• Spools of cellulose are unrolled
and broken into one square
inches.
• It is then loaded into heated
pressurized vessel containing N-
methyl morpholine N-oxide.
• Cellulose dissolves into a clear
solution.
Filtering
• In Amine Oxide solvent, cellulose is dissolved into a clear solution.
• It is then pumped out and filtered.
Spinning
• Cellulose is forced through the spinnerets and long strands of fiber comes out.
• These fibres are then dissolved in dilute Amine Oxide solution and is later
washed with water.
Drying And Finishing
• Fibre is passed through drying area.
• In the drying area, water is evaporated and lubricant is applied which may be
soap, silicone or other agent.
PROPERTIES Soft, strong, absorbent
Fibrillated during wet processing to produce special textures
It has high wet and dry strength, it is stronger than Cotton and Wool.
Wrinkle resistant
Very versatile fabric, dyeable to vibrant colours, with a variety of effects and
textures.
Can be hand washable
Simulates silk, suede, or leather touch
Good drapability
Biodegradable
Fine yarn counts can be spun
Comfort
• Soft, smooth fibre.
• Ideal for apparel that contacts skin.
• Thermal retention is poor.
Appearance Retention
• Resiliency is moderate- Wrinkles but not as severely as rayon.
• Shrinks, but not progressively.
• May have problems with fuzziness or piling.
Aesthetics
• Lustre, length and diameter can be changed depending upon end use.
• Processed to produce a range of surface effects.
• Offers unusual combinations of strength, opacity, absorbency.
Durability
• Performs more like cotton than rayon.
• Strongest of cellulosic fibres.
• Unique combination of soft hand and good durability, produces comfortable,
long-lasting textiles for apparel and interiors.
Care
• Either gently machine- Washable or dry cleaned.
• Sensitive to acids.
• Resistant to mild alkalis.
• Sensitive to mildew and some insects.
• High dye affinity.
• High inherent whiteness- Bleaching is not necessary.
PHYSICAL STRUCTURE
The physical structure is a more rounded
cross section & smoother longitudinal
appearance than rayon.
Since in the case of Lyocell we are just
dissolving cellulose in NMMO and not
making any cellulose derivatives, it has
a different molecular structure than
other regenerated cellulosic fibres.
The structure is ‘Homogeneous’ and
‘Dense’.
Cross Section
Longitudinal Section
APPLICATIONS Professional business wear.
Leotards
Hosiery
Casual wear
Upholstery
Window-treatment fabrics
Filters
Printers’ blankets
Specialty papers
Medical dressings
Conveyer belts for strength & softness
Botanic Tencel bed
Botanic Bed
There are three types of spinning are available for
spandex, these are-
Melt-spinning process.
Dry-spinning process.
Wet-spinning process.
Melt-spinning process :
athletic, aerobic
exercise apparel
swimsuits
ski pants
disco jean
hosiery
socks
underwear
surgical hose
support hose
motion capture suits
Home furnishings
Garments made with LYCRA® fiber are comfortable, durable
and keep their fit.
THANK YOU!