an improved cooling process for thermoplastic film webs , profiles , or shapes and interlocking closure profiles extruded onto film webs for use on reclosable bags or containers is provided . a mixture of a surfactant and water is used to cool film webs or closure profiles which have been extruded and secured onto a film web . the surfactant lowers the surface tension of the water , improving its wetting properties and providing faster cooling of the film . the resulting film structures are more stable and consistent in structure .