Fabric Info & Care

Mercerisation

I get asked this question a lot. What is Mercerisation?

Mercerisation is a process in cotton production. It is a treatment done in one or 2 stages that makes a cotton thread more wonderful, smooth and nicer to work with, which is why I am a fan of mercerised cotton fabrics and threads.

Invented back in the mid 1800s by a guy by the name of John Mercer. At the time, it wasn't so popular a method, but it was improved upon in the late 1800s with the help of industrialisation by another textile manufacturer H. A Lowe.

It is a method where the cotton is placed in a bath of dilute acid and it changes the composition of the fibre making it stronger and giving it a sheen. This makes it easier to dye and print onto, and when woven, a stronger fabric that can be woven finer and at a higher thread count. Mercerised cotton generally won't shrink or the shrinkage rate is far less as as its been pre shrunk under tension during its time in the acid bath.

The second optional stage of mercerisation is running the treated thread through a 'gasser', a gas burner flame, to singe off any little left over threads. This makes your thread super smooth. This second process is not always done, but if a cotton is 'gassed' this is the process it has been run through. 'Pearl' threads are usually gassed which is another reason they are super smooth and have a beautiful sheen.

Mercerisation is usually only done on long staple cotton, which is the more expensive cotton as the threads are long and more easily spun into thread. Types of long staple cotton are Egyptian, Sea Island and Pima. So if a fabric or thread you are working with is made with any of these, it will be a better quality.

The benefits of long staple cotton and mercerisation is you will have a fabric or thread that is easier to work with, stronger, wears and lasts longer, takes dye better so more saturated colours, drapes better, cuts and sews more easily and has less lint and a smoother surface with a nicer sheen. Also, it finger presses a treat and is easier to work with if you are doing small projects or paper piecing.

Mercerisation was the norm in the past for cotton fabrics and threads, but unfortunately its not as common these days, but you can get it and it is worth it. The little bit extra you pay, will come back 10 fold with how lovely it is to work with and how much nicer the finished product will look and it will last longer. A fantastic example of a mercerised cotton fabric is Liberty Tana Lawn, and we all know how lovely that is!

Vintage Rayon and Acetate

I was asked the other day about Rayons and Acetates. I'm a lover of Acetate fabric, I love its crunchy swishy sound and its ability to take bright colors. However in the discussion it ended up becoming a bit of a technical hiccup on weather or not these fabrics are natural, man made or synthetic. 

To answer this in a bit more detail and to get a tad round about, they are in a way both…

Although they are manufactured fibers, they are not considered synthetic. They are referred to generically as “regenerated cellulosic fibers” or "second generation cellulosics" due to the way they are manufactured. They are derived from wood pulp then chemically treated to create a fibre. But on the flip side they are not strictly natural fibers either as they are not produced directly or entirely from plants or animals. But when you break it down their properties are more closely aligned to natural cellulosic fibers, such as cotton and linen than petroleum-based synthetic fibers such as nylon or polyester.  

The technology behind these fabrics was developed in the mid to late 1800’s for other applications such as photography and early resins but was not applied as commercially viable fibers until the early 1900’s.

Rayon

Courtaulds Fibers produced the first commercial viscose rayon or artificial silk in 1905 and in the USA it was produced in 1910. However globally the fabric did not adopt the name ‘rayon’ until 1924.  Rayon gets its name from the hybrid of ‘sun rays’ due to its ability to handle bright color and have sheen and cotton due to its similar chemical structure. Sun ‘ray’ + cott ‘on’ made ‘Rayon’.

Now days more commonly referred to as ‘viscose’ as this is the main way of producing the fabric. But there are many methods for producing a rayon fiber and there are many sub classes such as Lyocell and companies producing fibers today. Modal and Tencel are modern brand names. But it’s all Rayon.
Vintage Rayon brands are Avicolor, Avril, Bemberg, Coloray, Cupioni, Englo, Enkrome and Zantrel.
Vintage rayon is highly collectable from day dresses and evening wear to Hawaiian shirts manufactured from the 40s and 50s.

1940's Rayon
Acetate 
The first commercially produced Acetate yarn was in the UK in 1912. Originally produced for crochet, sewing threads and trims due to its bright luster and dyeing properties. Acetate as a Fabric was produced after WW1 in Europe and was first made in the USA in 1924.



Some of you may have fabrics in your collection that are ‘Celanese’, this is one of the first branded ‘Acetate’ fabrics from the Celanese Company. Celanese was very popular in the 20’s and 30’s for making underwear and slips and often was printed with small florals or was quite pale in color.
Vintage acetate is also found very commonly as scarves and in garment linings and as taffetas, satins and brocades.
Other brand names are Acele, Avicolor, Aviso, Celaperm, Celara, Chromspun and Estron.

It gets even more confusing with some fabrics and processes being called ‘acetate rayons’ and with both the fibers being blended into cottons and silks…you can go about in circles, but the two fabrics are very closely related.

40s Acetate
Caring for your Vintage Rayon and Acetate 
Rayon and Acetate are both wonderful fabrics do have some pros and cons

They are both prone to creasing and will weaken and fade if exposed to light and both are not the strongest fabrics and this will worsen when wet so take care when laundering. Try to avoid soaking.

Always pre-wash rayon as it’s prone to shrinking

Gentle hand wash as you would a woolie – gently squish the suds through in a bath of luke warm water. Rinse well and do not wring or twist. If you have a front loader the gentle spin cycle for woolens might be an option to remove excess water.

Line dry away from direct sunlight.

Iron Rayon carefully while slightly damp. 
With Acetate do not use a hot iron as it will melt and can also ‘bruise’ so be careful if you are ironing a garment, be mindful of your seams.

Be careful with Rayon as it can develop heat shine, so a pressing cloth is helpful.

Also, watch for dye run off, many old acetates that are printed such as scarves have a tendency to bleed. If you are at all concerned, a trip to the dry cleaner could be the best option.

Make sure you store your garments clean. If storing fabric for a long period, it’s a good idea to refold every few months to avoid getting permanent creases.