Retroreflective articles comprising olefinic seal films
Assignee3M Innovative Properties Company
InventorsBimal V. Thakkar, Jeffrey O. Emslander, Steven M. Nielsen, Douglas J. Hall, David G. Schueler
Life of this patent
Estimating the term…
Abstract
Microstructured articles, such as a retroreflective articles, having a plurality of (e.g. cube-corner) microstructured elements and a seal film layer adhered to portions of the cube-corner elements and/or portions of a (e.g., flexible) body layer. The seal film is a thermoplastic polymeric material comprising reaction products of alkylene in an amount of at least about 50% and reaction products of at least one non-acidic polar monomer.
Claims26
A flexible retroreflective article comprising:
- a polymeric light transmissive body layer having an elastic modulus of less than 7×108 pascals;
- a plurality of cube-corner elements projecting from a major surface of the body layer;
- and
- a single layer or multilayered seal film adhered to at least portions of the body layer such that the seal film maintains an air interface with the cube-corner elements;
- wherein the seal film layer is a thermoplastic polymeric material comprising reaction products of alkylene in an amount of at least about 50% by weight and vinyl acetate in an amount of less than 25 wt %;
- wherein the seal film has a melt index of less than 25 g/10 min as measured according to ASTM D 1238.
A retroreflective article that comprises:
- a plurality of cube-corner elements;
- and
- a seal film layer adhered to portions of the cube-corner elements such that the seal film layer maintains an air interface with the cube-corner elements;
- wherein the seal film layer is a thermoplastic polymeric material comprising reaction products of alkylene in an amount of at least about 50% by weight and vinyl acetate in an amount of less than 25 wt %;
- wherein the seal film has a melt index of less than 25 g/10 min as measured according to ASTM D 1238.
A microstructured article that comprising
- a plurality of microstructured elements;
- and
- a seal film adhered to portions of the cube-corner elements such that the seal film maintains an air interface with the microstructured elements;
- wherein the seal film layer is a thermoplastic polymeric material comprising reaction products of alkylene in an amount of at least about 50% by weight and reaction products of vinyl acetate in an amount of less than 10 wt %;
- wherein the seal film has a melt index of less than 25 g/10 min as measured according to ASTM D 1238.
Dependencies are inferred from the claim text.