| 摘要 |
A monolayer printable polymeric film (11) and method for making the film. The film (11) is formed by mixing a structural material, such as prolypropylene or polyethylene, with a printable material, such as vinyl-acetate or methacrylate, to form a unitary mixture (21) prior to processing. The unitary mixture (21) is extruded and heated so as to cause the printable material to bloom to the surface of the unitary mixture (21). Stretching of the mixture at temperatures greater than permissible for multi-layered films formed of separate structural and printable materials heat sets and relaxes or stress relieves the film that is formed. The result is a monolayer film (11) that is stiffer and that lays much flatter than the prior multi-layered films that were prone to curling. The mixture is preferably heated to 130 deg. C or greater during the stretching process. The rollers (28) used to heat set the film during this heat-setting stage are preferably very smooth so as to enhance the transverse-direction strength of the film.
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