What is Mercerized Cotton?

What is Mercerized Cotton?

Posted by Vero Luxury Linens on Feb 21, 2019

Here is a little background. Raw cotton is not pure white; it is off-white. 

Raw Cotton boll - is off white.

Well, as we know, we like colored textiles. So textiles and specifically cotton fabrics are bleached and dyed. The problem with dying cotton is that as quickly as it accepts dye, it also quickly leaches the dye, out of the fiber especially when exposed to detergents and other chemicals.

Color fade is not a new issue and has plagued textile manufacturers for hundreds of years.

1844 John Mercer endeavors to solve this dilemma and develops a solution, that he rightly names Mercerizing.

Jorn Mercer invented Mercerizing for Cotton fabrics

Mercer found that color retention was markedly improved when the woven cotton fabric was treated with Sodium Hydroxide (SH).Hence Mercerizing was a solution to an age-old problem.

The Mercerizing process aided in color retention, but it had a significant drawback. Sodium Hydroxide changed the molecular structure of the cotton cells causing the fiber diameters to swell. This swelling shortened the individual fiber lengths resulting in shrinkage of the entire woven fabric by as much as 25%. As a result, Mercerizing was not used extensively as the loss of the fabric yield was not considered worth subjecting it.

In 1890 Horace Lowe developed a secondary process that changed everything. Lowe experimented with putting the fabric under tension while it was immersed in the Sodium Hydroxide bath. Not only did this virtually eliminate the shrinkage caused by the Sodium Hydroxide, but it also tightened the weave, making the fibers stronger. It also created a slight sheen to the textile which is considered a desirable attribute with bed sheets.

Mercerizing machine

Not all bed sheets are Mercerized. The reason is, Mercerizing is an extra step in the textile finishing process. Extra steps mean additional costs, some textile weavers elect not to spend the additional cost of this process with colored sheets.

We think that this extra step is well worth it.

Today, better textile weavers do Mercerize their textiles as the benefits far exceed the cost associated with this process.

To shop for our Luxury (Mercerized) Italian Bed Linens & Sheets, click the below Shop Here button.

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