Rowland William P: Retroreflective material. Rowland Development Corporation, August 15, 1972: US3684348 (253 worldwide citation)

Retroreflective material is provided by a composite synthetic plastic structure having a body portion with one smooth surface and another surface from which project a multiplicity of separately formed, minute cube corner formations having a side edge dimension of less than 0.025 inch. The cube corne ...

Rowland William P: Retroreflecting signs and the like with novel day-night coloration. Rowland Development Corporation, August 20, 1974: US3830682 (106 worldwide citation)

A retroreflective indicator providing differing day and night coloration is provided by a retroreflective material having a transparent fluorescent dye composition forwardly of the reflective surface which fluoresces light of a first wavelength band and transmits light of a second wavelength band. T ...

William P Rowland: Retroreflective sheeting and method and apparatus for producing same. Rowland Development Corporation, January 27, 1976: US03935359 (75 worldwide citation)

Retroreflective sheeting is produced by bonding a multiplicity of cube corner formations to sheet material, and the cube corner formations are formed principally of a first resin formulation providing the body thereof and a second resin formulation providing the base thereof and the bonding to the s ...

Nauta Jan P: Embossing rolls with areas of differential hardness. Rowland Development Corporation, July 8, 1975: US3893795 (43 worldwide citation)

An embossing roll for producing visual pattern effects on plastic sheet material is formed with a composite coating of synthetic plastic in which the surface layer has areas of greater resilience than other areas and has a multiplicity of closely spaced embossing formations thereon. The surface laye ...

Rowland William P: Emergency warning sign with readily collapsible frame. Rowland Development Corporation, February 19, 1974: US3792678 (11 worldwide citation)

A readily collapsible display device comprises a collapsible base structure on which a plurality of poles are detachably mounted. The poles are adapted to support a display member such as a sign or the like therebetween. The base structure consists of a pair of side base members to which a pair of e ...

Rowland William P: Highway retroreflecting marker. Rowland Development Corporation, December 9, 1975: US3924958 (10 worldwide citation)

A highway retroreflecting marker comprises a housing including a base having a relatively rigid side wall, and a resiliently depressible cap projecting upwardly from the base. The cap is substantially sealingly engaged with the side wall of the base. At least the cap of the housing is formed from a ...