striped films of the invention can have two or more preferably polymeric layers , of which at least one continuous or discontinuous layer includes a pigmented resin . the striped film is produced by modifying conventional coextrusion dies to restrict the flow of a pigmented melt stream . the result is a striped film useful for identifying the contents of a package made from the film , tamper evidence , counterfeit protection and verification of properties . the stripes can be of one or more colors , and vary in width and spacing . the pigment can be a material visible in ordinary light , or a material invisible in ordinary light but visible in e . g . ultraviolet light .