Polyester fleece is the most common material for throws and blankets, and it is durable, warm and cheap. It also degrades in a specific way that is entirely caused by how it is washed.
What Fleece Is
Polyester knitted and then brushed to raise the fibres. The raised pile traps air, and trapped air is what insulates.
It is not wool despite the name, and it behaves like a synthetic in every respect: it dries fast, does not absorb moisture, resists shrinking and holds colour well.
Why It Goes Flat and Bobbly
Two separate things happen. Heat melts and fuses the raised fibres, which flattens the pile permanently. Friction works short fibres loose, which then tangle into bobbles.
Both are caused by washing and drying rather than by use, which is why a blanket can look worse after six months of laundering than after two years on a sofa.
The Rules
- Cool wash, gentle cycle
- No fabric softener, ever
- Low heat or air dry, never a hot tumble dryer
- Wash alone or with similar items, not with towels or denim
- Never iron, since polyester melts
Care guidance published per item, of the kind at silverbuffalo.net, is worth reading once, since fleece throws are generally machine washable while much of the drinkware alongside them is not.
Why Fabric Softener Is Wrong
Softener works by coating fibres. On fleece that coating fills the spaces between the raised pile, which is exactly where the insulating air was.
The result is a blanket that feels slick rather than soft and insulates less. It also traps odour over time. White vinegar in the rinse achieves the softening effect without the coating.
Washing Alone
Fleece both sheds lint and attracts it from everything else. Washed with towels, it comes out covered.
Washing it separately, or with other synthetics, avoids both problems and reduces the friction that causes bobbling.
Removing Bobbles
A fabric shaver removes them quickly and safely. A sweater comb does the same more slowly.
Removing them does not stop new ones forming, though the rate usually falls once the initial loose fibres have gone.
Static
Fleece generates static in dry conditions, which is an irritation rather than a fault.
Air drying, wool dryer balls and a slightly humid room all reduce it. Fabric softener also reduces it and brings the coating problem with it.
Fire Safety
Worth knowing. Polyester melts rather than burning cleanly, and molten synthetic causes worse burns than a fabric that chars.
Fleece throws should be kept away from open flames, heaters and anything hot, and should not be draped over a lamp or a radiator to warm.
Storage
Clean and completely dry, in a breathable bag rather than sealed plastic. Fleece stored damp develops a smell that is difficult to remove.
