Abstract: Method of making at least two distinct, separate polymeric films. Embodiments of polymeric multilayer film described herein are useful, for example, for filtration or acoustic absorption.

Abstract: Polymeric multilayer film having first and second generally opposed major surfaces, an array of openings extending between the first and second major surfaces, and a thickness greater than 125 micrometers, wherein there are at least 30 openings/mm2, and wherein the openings each have a series of areas through the openings from the first and second major surfaces ranging from minimum to maximum areas, and wherein the minimum area is not at at least one of the major surfaces. Embodiments of polymeric multilayer film described herein are useful, for example, for filtration and acoustic absorption.

Abstract: Polymeric multilayer film having first and second generally opposed major surfaces, adjacent first and second layers that are separable from each other, and an array of indentations extending into the first and second layers. Polymeric multilayer film having first and second generally opposed major surfaces, an array of openings extending between the first and second major surfaces, and at least first and second adjacent layers that are separable from each other, wherein the openings each have a series of areas through the openings from the first and second major surfaces ranging from minimum to maximum areas, and wherein the minimum area is not at at least one of the major surface. Embodiments of polymeric multilayer film described herein are useful, for example, for filtration and acoustic absorption.