Multilayered film roll with reduced defects
AssigneeEastman Chemical Company
InventorsShiwei Liu, Mohtashim Saif, Hsifu Fan, Hua Ching Mark Lin, Stefaan Florquin, Ke Qin Thomas Yang
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Abstract
Devices, systems, and methods for preventing or reducing raised edges in wound films are disclosed herein. This improvement can be accomplished by employing a roll spacer that is narrower than the film and/or by entrapping a gas between the layers in the wound film. One or more embodiments of the present invention concern a multilayered wound film roll.
Claims25
A multilayered wound film roll comprising a central support assembly and a film wound around said central support assembly,
- wherein said central support assembly presents an outer support surface contacting an initial wound layer of said film,
- wherein each wound layer of said film comprises a main film body and a pair of outer edges extending along opposite sides of said main film body,
- wherein the average thickness of said outer edges is greater than the average thickness of said main film body,
- wherein the width of said outer support surface is less than the width of said initial wound layer of said film so that said outer edges of said initial wound layer of said film are not in contact with said outer support surface.
A process for producing a multilayered wound film roll, said process comprising:
- winding a film around a central support assembly to thereby form said multilayered wound film roll comprising a wound film,
- wherein said central support assembly presents an outer support surface that contacts an initial wound layer of said film during said winding,
- wherein each layer of said wound film comprises a main film body and a pair of outer edges extending along opposite sides of said main film body,
- wherein the average thickness of said outer edges is greater than the average thickness of said main film body,
- wherein the width of said outer support surface is less than the width of said initial wound layer of said film so that said outer edges of said initial wound layer of said film are not in contact with said outer support surface.
A vacuum roll-to-roll device, said device comprising:
- a roller configured to wind an initial film around a core thereby forming a wound film comprising a plurality of film layers;
- a rewind-controlling member configured to maintain a constant distance from the outermost layer of said wound film during winding on said roller;
- and
- a gas injection system configured to introduce a gas to be entrapped between said film layers during said winding on said roller, wherein the entrapped gas reduces the edge pressure of said wound film and minimizes the thickness variation in said wound film.
A process for producing a multilayered wound film roll, said process comprising:
- winding a film around a central support assembly to thereby form said multilayered wound film roll having a plurality of film layers;
- wherein said winding occurs in a vacuum,
- wherein a gas is injected between said film layers during said winding immediately before said film is wound around said central support assembly.
Dependencies are inferred from the claim text.