Broad sense
Any operation for improving the appearance or usefulness of a fabric after it leaves the loom or knitting machine. includes pretreatments such as washing, bleaching and coloration.
More difficult is often the second hurdle, the compatibility of the primary and secondary effef finishes that are being combined:
Questions
Could you give any examples about them?
Finishing
Chemical finishing
mechanical finishing
1.2 The challenge and charm of chemical finishing
Requirements of chemical finishes
coloration (dyeing or printing)
finishing
Finish definition
Narrow sense
Finishing completes the fabric’s performance and gives it special functional properties including the final ‘touch’. the final step in the fabric manufacturing process the last chance to provide the properties that customers will value.
the type of textile being treated (fibre and construction); The performance requirements of the finish (extent of effect and durability); the cost to benefit ratio; restrictions imposed on the process by availability of machinery,procedure requirements, environmental considerations; and compatibility of different formula components as well as the interaction of the finishing effects.
Chemical Finishing of Textiles
Qiang Wang
School of Textiles and Clothing Southern Yangtze University
content
1 Introduction to chemical finishing 2 Chemical finishing processes 3 Softening finishes 4 Hand building finishes 5 Easy-care and durable press finishes of cellulosics 6 Repellent finishes 7 Soil-release finishes 8 Flame-retardant finishes 9 Non-slip finishes 10 Antistatic finishes 11 Anti-pilling finishes 12 Elastomeric finishes 13 Finishes to improve colour fastness 14 Ultraviolet protection finishes 15 Antimicrobial finishes 16 Insect resist and mite protection finishes 17 Finishing with enzymes: bio-finishes for cellulose 18 Novel finishes 19 Actual and future trends in chemical finishing
1.3 Importance of chemical finishing
‘high tech’/high performance textiles
Chemical/functional finishes
one-tenth of the world’s fibre production
Any questions?
Other types of finishes typically reduce the main effect of a finish type, for example the flame retardant effect is decreased by nearly all other types of chemical finishes as they add flammable components to the fabric. Fortunately true antagonistic effects are rare, but true synergistic effects are also rare, where the resulting effect of a combination is greater than the sum of the single effects of the combined products. Examples of both cases are different types of flame retardants.
Any questions?
Objectives
woven
Sewing yarn with silicones
yarn
Denim washing
garment Finished objectives
knits
nonwoven
Finishing
Chemical finishing or ‘wet finishing’ Mechanical finishing or ‘dry finishing’
1
Typical Textile Processing Flow Chart
Typical Textile Wet Processing Flow Chart
outline
1.1 Wet and dry or chemical and mechanical finishing 1.2 The challenge and charm of chemical finishing 1.3 Importance of chemical finishing
Some effects are similar or assist each other, for example silicone elastomers cause water repellency, softeners bring about antistatic effects and antistatic finishes can be softening. Some effects are obviously contradictory, for example hydrophobic finishes and hydrophilic antistatic finishes, or stiffening and elastomeric finishes, or stiffening and softening finishes.
the hardest challenge of chemical finishing
several types of finishes are combined in one bath
First, all components of the finish bath must be compatible. Precipitations of anionic with cationic products have to be avoided. The emulsion stability of different products may be reduced byproduct interactions.
1.1 Wet and dry or chemical and mechanical finishing
1.1 Wet and dry or chemical and mechanical finishing
pretreatment (or preparation)
Textile wet processing