Temporary reusable retroreflective raised pavement marker

Abstract

The present invention incorporates to a new temporary, reusable, retroreflective, raised pavement marker design. The pavement marker utilizes a water soluble, adhesive embedded in a fibrous base material for application to the pavement. This temporary adhesion method allows the pavement marker to be reused after removal from the pavement. The semispherical shape of the marker provides increased lateral stability. The recesses on the top surface of the marker protect the retroreflective microspheres from loss of retrorefectivity from vehicular abrasion. The round shape also allows the marker to be used to form arrows and other pavement markings.

Claims

1. A raised pavement marker comprising: a base layer capable of adhering said raised pavement marker to a pavement surface; and a top component, comprising: a semispherical shaped plastic body with retroreflective glass microspheres embedded in said semispherical shaped plastic body, wherein, said raised pavement marker may be applied to said pavement surface, removed, and reapplied to said pavement surface, said base layer is capable of accepting an adhesive material for temporary adhesion to said pavement surface, said base layer is permanently attached to said top component, and said base layer is split microfiber material consisting of polyester and nylon fibers.

2. A raised pavement marker as recited in claim 1, wherein said base layer material has a density of 360-400 grams per square meter and is at least 0.125 inches thick.

3. A raised pavement marker as recited in claim 1, wherein said adhesive material is a polyvinyl acetate or other water miscible and remoistenable adhesive.

4. A raised pavement marker as recited in claim 1, wherein said top component is an abrasion resistant thermoset molded or injection molded resin with a hardness of D 70 to D 80.

5. A raised pavement marker as recited in claim 1, wherein said top component is about 4 inches in diameter and 0.1-0.4 inches in height.

6. A raised pavement marker as recited in claim 1, wherein said top component has a plurality of curved, longitudinal cavities radiating from its center.

7. A raised pavement marker as recited in claim 1, wherein said retroreflective glass microspheres are type 3 and exhibit a retroreflectance luminescence value of at least 200 mcd/m.sup.2/lux under standard condition of wetness and comply to federal specification TTB-1325.

Description

BRIEF DESCRIPTIONOF THE DRAWING

(1) FIG. 1 is a cross section view of the present invention.

(2) FIG. 2 shows the top view of present invention.

DETAILED DESCRIPTION OF THE INVENTION

(3) Referring now to the invention in more detail, FIG. 1 shows a cross section of the 4 components of the pavement marker device. The dome shaped plastic body 1 of the device has a plurality of recesses to protect the retroreflective glass microspheres from vehicle damage. The plastic body 1 is molded with a thermoset or injection molded resin. The body 1 is coated with a durable material 4. Retroreflective microspheres 3 are spread onto the wet coating 4 in a controlled manner that causes about 40% to 60% of the diameter of each microsphere to be embedded in the coating material 4. The plastic body 1 is about 4 inches in diameter and approximately 0.3 inches in height.

(4) The adhesive base layer material 2 is a woven split microfiber material that facilitates the adhesion of the device to the roadway surface. If thermoset resin is used the microfiber material 2 is welded to the resin 1 during the molding process when the plastic is in a molten state. If injection molding is used, the microfiber material 2 is welded to the body with a permanent waterproof adhesive. The polyester/nylon split microfiber material 2 shall have fiber diameters less than 0.2 denier. The thickness of the microfiber layer 2 shall be at least 0.125 inch and have a density of 360 to 400 grams per square meter. The microfiber material 2 shall not be made with recycled plastics. The washable adhesive is applied to the microfiber layer with a glue stick applicator before placement on the pavement. The marker remains stable if the microfiber layer 2 is soaked with water. The lateral stability created by the large coefficient of friction of the microfiber, the cohesive force of the water and the shape of the device is sufficient to eliminate any movement during use. If the water evaporates the adhesive dissolved in the water will bond the marker to the pavement.

(5) The top view in FIG. 2 shows the random distribution of the glass microspheres 3 and the spacing of the cavities in the body 1. The plastic body of the marker assembly is constructed to protect the glass microspheres from abrasion damage and not allow water and fine particles to accumulate on the reflective surface. The plastic body of the device must has retroreflective night ability, daylight visibility, uv resistance, and abrasion resistance that are not diminished by vehicle impacts or weather conditions. The surface of the raised marker is coated with a material that resists abrasion and hot tire marks. The retroreflectivity level of the marker shall not be less than 200 measured at standard 30-m geometry in units of mcd/m.sup.2/lux.