Wrinkle - What is a wrinkle?

Definition of WRINKLE:

In materials, a wrinkle is a defect in the surface of a pliable material that can appear as creasing, puckering, or any kind of distortion that interrupts the continuous smoothness of the material’s surface. Wrinkles can be caused by the manufacturing process or by environmental conditions, and commonly occur if the material is distorted by some kind of physical contact or when one layer or one area of an individual layer reacts differently to another, for example by drying faster than the surrounding area.

In labelling, the face material of a label may be wrinkled during manufacturing, printing, or during the process of applying the label to its intended substrate.