Abstract:
A photoluminescent retroreflective sheeting (10) for use in structures when a power outage occurs. Guidance systems are made from this sheeting to mark exits and escape routes as well as possible hazards and safety devices. The novel sheeting includes photoluminescent (14) properties that glow in the dark as well as retroreflective (12) properties that retroreflect light incident upon the same sheet such that only one sheet has to be used rather than individual sheets with separate properties.
Abstract:
The present invention provides retroreflective articles having microcubes and tools and methods for forming microcubes. One of the retroreflective articles comprises an array of microcubes; at least one microcube in the array is rectangular (110).
Abstract:
A method for producing a pelletized pavement marking mixture includes selecting an appropriate thermoplastic binder that is a solid at ambient temperatures and mixing the appropriate thermoplastic binder in a mixing vessel with a plasticizer and a filler to form a substantially evenly blended homogeneous pavement marking mixture by blending the pavement marking mixture for a period sufficient to substantially evenly distribute the plasticizer and the filler with the thermoplastic resin; transferring the substantially evenly blended pavement marking mixture from the mixing vessel to a compression pelletizer; and pelletizing the substantially evenly blended pavement marking mixture by compression. A pavement marking mixture consists of pellets, each of which consists of a substantially evenly blend of a thermoplastic binder, a plasticizer, and a filler. The method for making a pelletized pavement marking mixture can be extended by adding a pigment and retroreflective particles to the pavement marking mixture.
Abstract:
A potted shell style pavement marker (20) reinforced with fiberglass in the form of a mat of fiberglass strands (28) located near the bottom (30) of the marker or in the form of chopped fiberglass strands (32) distributed throughout the fill material (26). The mat (28) provides support against torsional or bending stresses near the bottom of the marker (30). The chopped strands (32) in the fill material (26) provide three-dimensional support throughout the height and depth of the fill in the interior of the housing (22). Both means of support are expected to reduce the number of cracks that develop in the fill (26), to prevent the expansion of any cracks which do develop, to prevent premature disintegration of the marker, and to increase average marker life. The supporting mat (28) and the chopped fiberglass strands (32) can be used together in a single marker.
Abstract:
A retroreflective unitary laminate material (322) having an acrylic layer (202) on which a sign legend (208) is printed and which is covered by an ultraviolet absorbent overlay (210) that has poor affinity for paint and low surface tension thus protecting the printed sign from deterioration due to weathering and enabling the sign to be readily cleansed without damaging the printed signs, and minimizing water beading on the sign front face.
Abstract:
A roadway marker (30, 50) comprises a solid body member having a lower generally planar surface (34) configured to be adhered directly to a roadway surface. The marker (30, 50) is injection molded as a one-piece structure from a closed-cell foam thermoplastic material using a chemical blowing agent. The bottom surface (34) of the body may be formed with slight recesses (36) or protrusions (52) such that the entire bottom of the marker fills with adhesive (40, 54) when the marker is installed. Thus, maximum adhesive surface area is provided between the marker and the roadway surface. Further, the closed-cell foam construction creates a marker body which is strong, economical to mold and which does not shrink after molding.
Abstract:
Cellular retroreflective sheeting (40) comprises a first film (10) of thermoplastic material which has been formed to define arrays of minute cube-corner reflective elements (12) on one face thereof. The reflective elements are covered with a second thin thermoplastic film (36) and the two films together pass over a patterned roller where a series of sonic welding heads (50) rapidly bond the films together forming small cells (52) of retroreflective cube-corner elements (12) in the pattern of the roller. Because the heat generated in the welding process is localized to the pattern of the roller, cell walls may be formed having narrow thickness yet good bonding of the films is achieved. Further, residual heat does not appreciably transfer to adjacent retroreflective elements (12), therefore, distortion of adjacent elements is minimized and a sheeting (40) construction is achieved having superior brilliance and durability as well as maximum retroreflective capability over a wide angular range of incident light. Also disclosed is a method for forming such sheeting (40).
Abstract:
A roadway marker comprises a shell (30) molded of suitable plastic and having an internal honeycomb configuration. A base plate (42) extends over the lower surface of the shell covering the honeycomb arrangement and defining a plurality of chambers (38) internal to the shell. The plate is provided with a plurality of apertures (50), each opening to a chamber (38). When the marker is installed, adhesive material flows through the apertures (50) and into the chambers (38). Before the adhesive sets, it forms mushroom-shaped configurations (58) over the top inside surface of the plate (42). The mushroom-shaped configurations (58) create a strong mechanical bond between the plate and the associated roadway surface. The large lower surface area of the plate (42) also enhances bonding of the marker to the roadway (54).
Abstract:
A photoluminescent retroreflective sheeting (24) for use in structures when a power outage occurs. Guidance systems are made from this sheeting to mark exits and escape routes as well as possible hazards and safety devices. The novel sheeting (24) includes photoluminescent properties that glow in the dark as well as retroreflective properties that retroreflect light incident upon the same sheet (24) such that only one sheet has to be used rather than individual sheets with separate properties.