Cellulose triacetate, also known simply as triacetate, CTA and TAC, is manufactured from cellulose

Cellulose

Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....

 and a source of acetate

Acetate

An acetate is a derivative of acetic acid. This term includes salts and esters, as well as the anion found in solution. Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In...

 esters, typically acetic anhydride

Acetic anhydride

Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula 2O. Commonly abbreviated Ac2O, it is the simplest isolatable acid anhydride and is a widely used reagent in organic synthesis...

. Triacetate is typically used for the creation of fibres and film base

Film base

A film base is a transparent substrate which acts as a support medium for the photosensitive emulsion that lies atop it. Despite the numerous layers and coatings associated with the emulsion layer, the base generally accounts for the vast majority of the thickness of any given film stock...

.
It is similar chemically to cellulose acetate

Cellulose acetate

Cellulose acetate , first prepared in 1865, is the acetate ester of cellulose. Cellulose acetate is used as a film base in photography, as a component in some adhesives, and as a frame material for eyeglasses; it is also used as a synthetic fiber and in the manufacture of cigarette filters and...

, with the distinguishing characteristics being that in triacetate, according to the Federal Trade Commission

Federal Trade Commission

The Federal Trade Commission is an independent agency of the United States government, established in 1914 by the Federal Trade Commission Act...

 definition, at least "92 percent of the hydroxyl

Hydroxyl

A hydroxyl is a chemical group containing an oxygen atom covalently bonded with a hydrogen atom. In inorganic chemistry, the hydroxyl group is known as the hydroxide ion, and scientists and reference works generally use these different terms though they refer to the same chemical structure in...

 groups are acetylated." During the manufacture of triacetate the cellulose is completely acetylated whereas in regular cellulose acetate or cellulose diacetate, it is only partially acetylated.