Are rayon and acetate the same thing?

No, though both are made from cellulose and both were sold as artificial silk. Rayon is regenerated cellulose, chemically close to cotton, while acetate is cellulose acetate, a different compound. Acetate is glossier and crisper but weaker and more solvent-sensitive.

Why does acetate melt or dissolve so easily?

Because cellulose acetate is sensitive to heat and is actually dissolved by acetone and related solvents, which is why nail-polish remover can ruin an acetate garment and why acetate is almost always dry-clean only.

Which is more comfortable to wear?

Rayon, generally. It breathes and absorbs moisture like a natural fiber, while acetate is less breathable and less absorbent and is chosen mainly for its sheen and drape rather than comfort.

Side by side

Rayon vs Acetate

Rayon and acetate are the two early manufactured fibers, both made from natural cellulose rather than petrochemicals, and both first sold as artificial silk. But they are made differently and behave differently. Rayon regenerates the cellulose into nearly pure cellulose thread, so it breathes and absorbs like a natural fiber. Acetate chemically converts the cellulose into a new compound, giving a more lustrous, crisper, silk-like cloth that is weaker and far fussier to care for.

Rayon

No. 119

woven from regenerated cellulose · first documented 1890s

Acetate

No. 120

woven from cellulose acetate, often satin · first documented 1920s

The differences

Aspect	Rayon	Acetate
Chemistry	Cellulose dissolved and reformed as nearly pure cellulose fiber (regenerated).	Cellulose converted to cellulose acetate, a new compound, before spinning.
Hand and look	Soft, fluid, matte to softly lustrous; drapes like silk.	Crisper, with a higher, glossier satin sheen.
Comfort	Breathable and absorbent, comfortable against the skin.	Less absorbent and less breathable; prized for look over comfort.
Care	Weak when wet, can shrink; many rayons need gentle or dry cleaning.	More delicate still: heat-sensitive, dissolved by acetone and some solvents, usually dry-clean only.
Typical use	Dresses, blouses, linings, blends where drape matters.	Linings, eveningwear, satin, taffeta, anywhere sheen leads.

Which to choose

Choose rayon when you want a breathable, fluid, silk-like cloth that is comfortable to wear. Choose acetate when you want maximum sheen and crisp body for a lining or evening fabric and are willing to treat it gently. Both reward careful washing, but acetate is the more fragile of the two.

Common questions

Are rayon and acetate the same thing?: No, though both are made from cellulose and both were sold as artificial silk. Rayon is regenerated cellulose, chemically close to cotton, while acetate is cellulose acetate, a different compound. Acetate is glossier and crisper but weaker and more solvent-sensitive.
Why does acetate melt or dissolve so easily?: Because cellulose acetate is sensitive to heat and is actually dissolved by acetone and related solvents, which is why nail-polish remover can ruin an acetate garment and why acetate is almost always dry-clean only.
Which is more comfortable to wear?: Rayon, generally. It breathes and absorbs moisture like a natural fiber, while acetate is less breathable and less absorbent and is chosen mainly for its sheen and drape rather than comfort.

Full entry: Rayon Full entry: Acetate

Sources & References

1.Rayon, Wikipedia
2.Viscose, Wikipedia
3.Cellulose acetate, Wikipedia
4.Acetate, Wikipedia