Method for making permeable retroreflective sheeting
AssigneeMinnesota Mining and Manufacturing Company
InventorsVera L. Lightle, Johann F. Petersen, Wallace K. Bingham
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Abstract
Flexible, self-supporting, air-permeable retroreflective sheeting comprising a two-sided, self-supporting, air-permeable web of thermoplastic filaments with retroreflective elements partially embedded in the filaments on one side of the web. On the other side of the web, the surfaces of the filaments are substantially free of retroreflective elements. In some embodiments, the web may be used as a bonding agent to secure the sheeting to a desired substrate.
Claims11
A process for making a flexible, self-supporting, air-permeable retroreflective sheeting comprising the following steps:
- a) providing a monolayer of retroreflective elements releasably secured to a temporary carrier sheet;
- b) heat-laminating an air-permeable web of thermoplastic filaments to said retroreflective elements, said filaments softening and flowing sufficiently to bond to said retroreflective elements but not flowing to such an extent that the air-permeability of said web is reduced to below about 5 liters/minute;
- and
- c) stripping away said carrier sheet.
Dependencies are inferred from the claim text.