Fantastic swatches, secondlooks!
I've just found an early 1960s book called 'Man-Made Fibres' on my shelf, that's probably aimed at schoolkids so its more or less understandable for me at least.
It explains that rayon, acetate and triacetate are all classified as 'cellulosic' fibres, being derived from cellulose 'in the form of wood pulp or cotton linters.' So as everyone's been saying, they're all one big happy family!
Let's summarise, there's a lot here!
VISCOSE RAYON - made of wood pulp, goes through various soaking and ageing processes until its a viscous liquid resembling honey. If left untreated at this point it makes fibres with "a high degree of lustre," but if a dull sheen is required "a special pigment - usually titanium dioxide - is added."
*da dee dee* *reading on*
Quote: "Courtauld's first venture into the field of 'artificial silk,' as rayon was then called, took place in the 1890s, and in 1904 Samuel Courtauld & Co. bought the British patent rights of Cross, Bevan and Stearn to the viscose process . . . Courtaulds also founded the viscose rayon industry in America, and in 1909 formed the American Viscose Co. which later became the Viscose Corporation of America."
CELLULOSE ACETATE: made from either cotton linters or wood pulp, different process to viscose (gets technical, involves acetic acid).
Quote: "The acetate process produces a filament quite different in its chemical nature from that given by the viscose process. For one thing the acetate filament is thermoplastic, and so can be softened by the application of heat. Acetate materials can therefore be embossed with patterns and similar effects. Moreover the handle of such material is particularly soft and it does not absorb moisture to the same extent as viscose rayon. Acetate yarns are marketed under many different trade names, of which 'Celanese,' manufactured by British Celanese Ltd., is possibly the best known in this country."
TRIACETATE: "is a development from regular acetate and is made from the same basic raw materials. In addition to possessing the advantages of acetate it has a number of other properties similar to those of fully synthetic fibres. Though similar in strength and appearance to acetate, it is more resistant to continuous wear. Triacetate, both in filament and spun staple form, is marketed by British Celanese Ltd. under the trade name of 'Tricel.' 'Arnel' is the American equivalent."
I think I'm getting a handle on this now! :embaressed: