Method of manufacturing plastic particles for a particle display

Claim 1

A process for making a generally spherical plastic particle composed of first and second substantially hemispherical portions of two distinct colors, the first portion including a material which imparts a predetermined electrical property thereto which is different from electrical properties of the second portion, the process comprising adding to a heated liquid bath non-spherical particles consisting of a first layer of plastic having a first color, said first layer including a material which imparts a predetermined electrical property thereto, a second layer of plastic having a second color, said second layer including a material which imparts electrical properties thereto different from said first layer, said non-spherical particles having been formed by extruding said first and second layers of plastic in the shape of an elongate rod having said first and second layers adjoining one another centrally of and along said rod, said rod having been cut into predetermined lengths where the resultant aspect ratio of fiber length to diameter is in the range of 0.5 up to 5.0, establishing in said bath a temperature which is sufficient to cause melting of said first and second layers of plastic, an anti-agglomerating agent, being present in said bath to preclude melting particles of plastic adhering to one another, allowing such melting particles to form spheres in said bath, solidifying said spheres in said bath and removing said spheres from said bath.