Textile wet processing can be thought of having three stages, pretreatment, coloration and finishing. Finishing in the narrow sense is the final step in the fabric manufacturing process, the last chance to provide the properties that consumers will value.
Chemical finishing in textile involves the addition of chemicals to textile to achieve desired result. Typically, the appearance of fabric remains unchanged after chemical finishing. But Mechanical or Dry finish uses mainly physical means to change fabric properties and usually alters the fabric appearance as well. Mechanical finishing includes calendering, emersing, compressive shrinkage, raising, brushing, shearing etc. Often mechanical and chemical finishing overlap. Some mechanical finishes need chemical application. So, chemical finish plays an important role in textile finishing field.
In this article, we will briefly discuss about chemical finishing.
General requirements of chemical finishing in textile
Primary effects of finishes
High effect level at low cost for products and application
Possible effect design, adaptation to consumer wishes, article demands and favoured use
Desired secondary effect
Usable for all kind of fibers and textile forms, as yarn, woven or knit garment, non-woven
High performance for washing and dry cleaning of garments and most household chores
No loss of important textile qualities such as tear strength and abrasion resistance, comfort, appearance, hand
No yellowing of undyed fabrics, no shade change of colored ones, no reduced color fastness
Easy and safe handling, non-flammable
Simple application, preferably with several standard methods and equipment at low cost
High stability under storage and application conditions (temperature, pH, mechanical stress)
Even distribution, either on the fiber or fabric surface or inside the fabric
Compatibility with other finishes
Synergistic effects, no reduction of effect of other finishes
Easy correction of finishing faults such as removal of finish or stains
No environmental problems, non-toxic, bio-degradable, no volatile organic compounds
Importance of chemical finishing in textile
Chemical finishing in textile has always been an important fact but the recent trend to “High Tech” product adds a great popularity to it.
As the use of high performance textiles has grown, the need for chemical finishes to provide the fabric properties required in these special application has grown accordingly
It is estimated that globally in one year, the amount of textile chemical auxiliaries sold and used is one-tenth of the world’s fiber production
About 6 million tons of chemicals are consumed for 60 million tons of fiber
About 40% of textile auxiliaries are used in finishing, the largest percentage usage of all textile chemicals, followed by dyeing and printing auxiliaries and pretreatment chemicals.
Within the textile finishing group, the product breakdown, based on TEGEWA, is given as a survey in the following table.
In terms of value, the repellent group is the leader with the highest ratio of cost per amount.
This reflects the relatively high cost of the fluorochemical subgroup of repellents.
Importance of the finishing product groups in order
Finishing product group
Soft handle products based on: silicones, including elastomeric, cationics, non-ionics, without silicones anionics
Repellents based on: Fluorocarbons, paraffins, silicones
Products for coating, laminating, fiber and thread bonding
Products for easy care and permanent press finishes
Antimicrobial products, including protection from germs
Antistatic agents including carpet finishing
Products for soil-release, remainder, including brighteners, products for sewing thread preparation, anti-felting of wool, carpet back-coating, hydrophilation, delustering and brightening, foaming of finishes
Different types of chemical finishing in textile
Flame Retardency finish
Water Repellency finish https://www.britannica.com/topic/water-repellent-fabric
Silicon treatment for hydrophobic effect
Fluoro chemicals for soil release & soil resistance
Certain phosphorous & nitrogen compounds for flame retardant
Finish with non-slip agents
Wrinkle free or crease resistant finish
Chemical finishing, an important field for textile finishing covers a broad market share. In our subsequent articles, we will know more about it.
Salma Hasin Shila, the author of this site completed her BSc. in Textile Engineering (Wet Processing Engineering) from Bangladesh University of Textiles www.butex.edu.bd (BUTEX). She has a passion for textile technology and love to write about it. She wants to share her knowledge to help the students in their studies and businessman & entrepreneurs in their business in making wise decisions fast.