Prevention of groove tip deformation in brightness enhancement film
AssigneeMinnesota Mining and Manufacturing Company
InventorsTodd R. Williams, Daniel J. Kingston
Life of this patent
Estimating the term…
Abstract
A method of producing a microstructure bearing article that includes the steps of molding the microstructure on the base, curing the resin that forms the microstructure, and heat treating the microstructure. The heat treating is performed at a temperature that is at least equal to a normal glass transition temperature of the resin. The heat treating raises the glass transition temperature of the resulting polymer above approximately 333.degree. K. such that groove tip impression is reduced. Such articles are useful in backlit displays which are useful in computers and the like.
Claims29
A method of improving groove tip impression resistance in a microstructure bearing article, the method comprising:
- forming a desired microstructure in a first layer on a base from an oligomeric resin;
- curing the resin of the first layer;
- and
- heat treating the first layer at a temperature that is at least equal to a normal glass transition temperature of the resin, the heat treating raising the glass transition temperature of the resulting polymer above about 333.degree. K. such that groove tip impression is reduced.
A method of forming a microstructure bearing article that exhibits reduced groove tip impression, the method comprising:
- preparing an oligomeric composition;
- depositing the oligomeric resin composition onto a master negative microstructured surface or onto a substrate in an amount barely sufficient to fill cavities of the master;
- filling the cavities by moving a bead of the oligomeric resin composition between the substrate and the master, at least one of which is flexible, the oligomeric resin composition forming the desired microstructure;
- curing the oligomeric resin that forms the desired microstructure;
- and
- heat treating the desired microstructure at a temperature that is at least equal to a normal glass transition temperature of the resin, the heat treating raising the glass transition temperature of the resulting polymer above about 333.degree. K. such that groove tip impression is reduced.
Dependencies are inferred from the claim text.