Polyester dresses are sometimes labelled as "dry clean only" due to their delicate nature and potential for damage during regular washing. Polyester is a synthetic fabric that can be prone to issues like shrinking, colour fading, or fabric pilling when exposed to the harsh conditions of a washing machine. Polyester dresses dry cleaning, done by professionals with specialised equipment and gentle solvents, is a safer option for maintaining the integrity of these garments.

However, not all dresses necessarily require polyester dresses dry cleaning. Many can be hand-washed or machine-washed on a gentle cycle with a mild detergent. Always check the care label for specific instructions, as some polyester blends or intricate designs may still warrant professional dry cleaning to ensure they stay in good condition. It's essential to follow care guidelines to extend the lifespan of your polyester dresses and prevent any potential damage.

Original Source: https://www.quora.com/Why-are-some-polyester-dresses-dry-clean-only/answer/Hello-Laundry