초록 ▼

A process and apparatus for providing microperforations in a zippered film useful for manufacturing reclosable zippered produce bags including (a) providing a web of thermoplastic film with zipper profile members on at least one side of the web, the zipper profile members spaced apart on the web for

A process and apparatus for providing microperforations in a zippered film useful for manufacturing reclosable zippered produce bags including (a) providing a web of thermoplastic film with zipper profile members on at least one side of the web, the zipper profile members spaced apart on the web forming a central web area between the profiles; (b) feeding the web between the nip of a cylinder having a plurality of heated pins and a pressure roller such that a plurality of microholes are formed in the central web area between the zipper profile members; and (c) maintaining the web in feeding alignment between the pin cylinder and the pressure roller such that uniform sized microholes are perforated in the web area between the profile members.

대표청구항 ▼

An apparatus for preparing a microperforated zippered thermoplastic film web stock useful for producing a zippered produce bag comprising: (a) means for providing a web of thermoplastic film with zipper profile members on at least one side of the web, the zipper profile members spaced apart on the w

An apparatus for preparing a microperforated zippered thermoplastic film web stock useful for producing a zippered produce bag comprising: (a) means for providing a web of thermoplastic film with zipper profile members on at least one side of the web, the zipper profile members spaced apart on the web forming a central web area between the profiles; (b) means for feeding the web between the nip of a cylinder having a plurality of heated pins and a pressure roller such that a plurality of microholes are formed in the central web area between the zipper profile members; (c) means for maintaining the web in feeding alignment between the pin cylinder and the pressure roller such that the web area between the profile members is microperforated in a uniform microhole size; and (d) a means for detecting the film web wrapping around the pin cylinder.