Durable fluorescent organic pigments and methods of making
Assignee3M Innovative Properties Company
InventorsR. Ellen Harelstad, David M. Burns, Lee A. Pavelka
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Abstract
Daylight fluorescent articles are disclosed that utilize durable fluorescent pigment particles resulting from a fluorescent dye incorporated within a matrix polymer selected from polycarbonate, polyester and mixtures thereof and where the particles are of various desired shapes and sizes. Embodiments of such fluorescent pigment particles may also be retroreflective and are especially useful for pavement marking surfaces and retroreflective products for highway transportation safety.
Claims22
A fluorescent pigment comprising in particle form:
- a fractured retroreflective sheeting comprising
- a fluorescent dye selected from the group of thioxanthone, perylene, perylene imide, xanthene compounds and mixtures thereof;
- incorporated into
- a polymeric matrix selected from the group of polycarbonate, and mixtures thereof.
A fluorescent article, comprising:
- a binder having a first major viewing surface;
- and
- fluorescent pigment comprising, in particle form, fractured retroreflective sheeting comprising a fluorescent dye selected from the group of thioxanthone, perylene, perylene imide, xanthene compounds and mixtures thereof;
- and
- a polymeric matrix selected from the group of polycarbonate, polyester and mixtures thereof;
- wherein the fluorescent dye is incorporated in the polymeric matrix;
- and wherein at least some of the fluorescent pigment particles are disposed on or in the binder so as to be visible on the first major viewing surface of the binder.
A method of making a fluorescent article, comprising the steps of:
- providing at least one fluorescent dye selected from the group of thioxanthone, perylene, perylene imide, xanthene compounds, and mixtures thereof;
- providing a polymer matrix selected from the group of polycarbonate, polyester, and mixtures thereof;
- extruding a mixture of said fluorescent dye and the polymer matrix;
- fracturing the extrudate to form a fluorescent pigment in a particle form;
- and
- disposing the fluorescent pigment on or in a binder to form the fluorescent article.
Dependencies are inferred from the claim text.