Mercerised cotton

Mercerized cotton yarn reels
Spool of a two-ply mercerized cotton thread with a polyester core.

Mercerisation is a textile finishing treatment for cellulose fabric and yarn, mainly cotton and flax, which improves dye uptake and tear strength, reduces fabric shrinkage, and imparts a silk-like luster.

Development

The process was devised about 1844 by John Mercer, who treated cotton with solutions of 55–65 ° Twaddell scale (20–30%) sodium hydroxide followed by washing. Mercer observed that the treatment shrank the fabric and increased its tensile strength and affinity for dyes. In the original process of Mercer, no tension was applied. The product was termed fulled cotton, a nod to the process of fulling in woven wool fabric. Mercer regarded the increased affinity for dyes as the most important technical aspect. Mercer also experimented with sulfuric acid and zinc chloride solutions and discovered the parchmentising effect of sulfuric acid.[1]

The silk-like lustre now commonly associated with mercerising is produced by tension and was discovered by Horace Lowe in 1890.

Process

Treatment with sodium hydroxide destroys the spiral form of the cellulose with formation of alkali cellulose, which is changed to cellulose hydrate on washing out the alkali. Caustic soda concentrations of 20–26% are used. Effective mercerization requires the use of wetting agents.[2]

The improved lustre of mercerised cotton is due to the production of nearly circular cotton fibres under tension. Another characteristic feature is the untwisting (deconvolution) of the cotton hair.

In dry mercerization, the process is carried out while drying the fabric on a stenter.

References

  1. ^ J. T. Marsh (1948), "Dispersion Processes", An Introduction To Textile Finishing, pp. 111–133
  2. ^ "Textile Auxiliaries", Ullmann's Encyclopedia of Industrial Chemistry (7th ed.), 2007, doi:10.1002/14356007.a26_227

External links

Media files used on this page

Jute nahtlos.png
Author/Creator: SoylentGreen, Licence: CC-BY-SA-3.0
Hessian Fabric made seamless. It will serve to create a normal map in Blender.
Batik Indonesia.jpg
Author/Creator: MartijnL, Licence: CC BY-SA 3.0 nl
Batik cloth purchased in Yogyakarta, Indonesia
MacLachlan hunting tartan (D. W. Stewart).svg
Author/Creator: , Licence: CC BY-SA 2.5
A representation of the Maclachlan hunting tartan. This tartan is the oldest tartan to bear the name MacLachlan. This tartan is referred to as the Old MacLachlan, MacLachlan, and Hunting MacLachlan. This sett was first published in Old & Rare Scottish Tartans by D. W. Stewart in 1893.
Thread count: Y6, W4, Bk32, G32, Y6, W4, R48.
Sources: MacLachlan Clan Tartan WR1710 MacLachlan Hunting Tartan
Spool of white thread.jpg
Author/Creator: No machine-readable author provided. Dmeranda assumed (based on copyright claims)., Licence: CC-BY-SA-3.0

A spool of white all purpose thread for sewing. The spool is approximately 3cm in diameter and 3cm high, and contains 123m (135 yards) of thread which is about 0.2mm thick. The thread is a 2-ply construction with right-handed Z-twist, with each ply composed of 37% mercerized cotton wrapped around a 63% polyester monofilament core. Viewing in closeup shows the right-handed Z-twist as well as the tiny individual staples making up the cotton wrapping.

Taken with a Sony A100 camera using a Sony 2.8/100 Macro lens. Multiple lighting sources were used to show texture and sheen. Image has not been edited.
Bobinas de hilo de algodón mercerizado - Cotton thread reels.jpg
Author/Creator: johannrela, Licence: CC BY 2.0
Mercerized cotton thread reels