What is Mercerised cotton?
{{complex|date=December 2023}} [[File:Bobinas_de_hilo_de_algodón_mercerizado_-_Cotton_thread_reels.jpg|right|thumb|Mercerized cotton yarn reels]] [[File:Spool_of_white_thread.jpg|right|thumb|Spool of a two-ply mercerized cotton thread with a polyester core.]] '''Mercerisation''' is a textile [[finishing treatment]] for [[cellulose]] [[Textile|fabric]] and [[yarn]]. It is mainly used for [[cotton]] and [[flax]]. The process changes the properties of the materials: They can be colored more easily, they [[Tensile strength|withstand tearing better]], and the fabric will shrink less, when washed. Fabrics treated that way also have a [[Luster (mineralogy)|luster]] which make them resemble [[silk]] in some ways. Sometimes, cotton treated that way is called ''Fil d'écosse''. Sometimes wool treated in the [[Mercosett process]] is also called mercerised. The process of mercerisation is long, and relatively costly. For this reason, only higher quality [[Textile|textiles]] are treated that way. == Development == About 1844, [[John Mercer]] developed the process. He noticed that when he treated cotton with [[Solution|solutions]] of [[sodium hydroxide]], this changed the properties of the cotton: The fabric shrank, and had a higher resistance to tearing. It was also easier to color the material using [[Dye|dyes]]. In the original process of Mercer, no [[Tension (mechanics)|tension]] was applied. The product was termed ''fulled cotton'', a nod to the process of fulling in woven wool fabric. For Mercer, making the material easier to color was the most important technical aspect. Mercer also tried with [[sulfuric acid]] and [[zinc chloride]] solutions and discovered the parchmentising effect of [[sulfuric acid]].<ref>{{Citation|last=J. T. Marsh|chapter=Dispersion Processes|title=An Introduction To Textile Finishing|year=1948|pages=111–133|url=https://archive.org/details/in.ernet.dli.2015.6810}}</ref> The [[silk]]-like lustre now commonly associated with mercerising is produced by tension and was discovered by [[Horace