Waviness: Waviness (起拱)
An undulating or puckered appearance along a sewn zipper, caused by a mismatch in shrinkage between tape and shell fabric, excessive sewing tension or unstable setting. Waviness spoils the look of plackets and openings and may worsen after washing. Prevention includes pre-shrinking the tape, matching shrinkage, controlling feed tension and using appropriate seam allowance. Finished garments are checked after pressing and after a wash test.