text: fig1 illustrates a top plan view of a pavement marking system of the instant invention for use in conveying the message “ thank you ”, such as might be used on the pavement surface at the automobile exit point of a fast - food restaurant drive - through lane . in this embodiment of the invention , the legend layer 10 comprises each individual letter of the message “ thank you ”, although for clarity in the drawing the reference numeral has a reference line to only one such letter . each letter of the legend layer is a precut piece of preformed thermoplastic material in one or more colors that contrasts with the color of background layer 12 . background layer 12 is a separate piece of pre - cut preformed thermoplastic material having outer edges 12 a , 12 b , 12 c , and 12 d , and being of a color that contrasts with legend layer 10 . background layer 12 can be applied to the associated pavement surface by known means such as appropriate adhesives or fusing in place with a heat gun or flame torch . fig2 and 3 are cross - sectional views of alternative embodiments of the pavement marking system of fig1 . in the embodiment of fig2 background layer 12 is provided with a plurality of orifices 14 , only one of which is indicated in the drawing for sake of clarity , each orifice 14 being pre - cut to correspond in size and shape with one of the letters of legend layer 10 . for installation , background layer 12 is placed on the pavement surface where installation is desired , and is affixed thereto such as with an adhesive or by fusing with a heat gun or flame torch . the pre - cut letters of legend layer 10 are then placed in an in - laid manner within the precut orifices 14 of background layer 12 , and affixed to the pavement surface by any of the same techniques , i . e ., adhesives or by fusing with a heat gun or flame torch . alternatively , background layer 12 can be placed on the pavement surface and the letters of legend layer 10 placed in their corresponding orifices 14 in background layer 12 ; then the legend layer and background layer can be affixed to the pavement surface simultaneously , such as by fusing with a flame torch . the embodiment of fig2 may be preferred in those applications in which it is desirable that the top surface of the legend layer 10 of the pavement marking system be substantially flush with the top surface of the background layer 12 . such applications can include those applications in which the pavement surface may be subjected to snowplowing . in such applications , it also may be desirable for the regions of background layer 12 adjacent to outer edges 12 a , 12 b , 12 c , and 12 d to be provided with a chamfer 15 , to reduce the likelihood of a snowplow blade prying into background layer 12 and tearing or dislodging it . in the embodiment of fig3 there are no orifices in background layer 12 corresponding to each of the letters of legend layer 10 . instead , the letters of legend layer 10 are simply applied directly onto the top surface of background layer 12 . for installation , background layer 12 is placed on the pavement surface where installation is desired , and is affixed thereto such as with an adhesive or by fusing with a heat gun or a flame torch . the pre - cut letters of legend layer 10 are then placed directly onto the top surface of background layer 12 , and affixed thereto by any of the same techniques , i . e ., adhesives or by fusing with a heat gun or flame torch . further , although no chamfered edge 15 is illustrated in fig3 it will be appreciated that this optional feature could be included in the embodiment of fig3 if desired . use of the pavement marking system of the instant invention greatly facilitates the surface treatment of the associated pavement such as with a black coating . if the area of the background layer 12 between the edge of the legend layer 10 and the nearest edge 12 a , 12 b , 12 c , or 12 d of the background layer 12 is wide enough such as at 18 , then the black coating can be applied right up to and slightly over those edges of background layer 12 , without coming into contact with legend layer 10 . alternatively , the black coating can be applied to the pavement surface adjacent to the edges 12 a , 12 b , 12 c , and 12 d of background layer 12 , and spread up to the edges and outwardly therefrom such as with a squeegee tool . the edges of background layer 12 preferably define a simple geometric shape to facilitate this step . in the embodiment of fig1 - 3 , the shape of background layer 10 is generally rectangular , although the invention is not limited to such shapes . black coating is then applied to the pavement surface up to and overlapping the previously applied black coating around the pavement marking system of the invention , so that the black coating does not have to come into contact with either the legend layer 10 or the background layer 12 . background layer 12 is preferably black . this provides enhanced visual contrast with legend layer 10 , particularly as the surrounding pavement surface fades over time to a light gray . such enhanced visual contrast provides greater conspicuity of the message conveyed by the legend layer 10 . a black background 12 also will not show any stains or discoloration should any black coating come in contact with the background layer . in accordance with the invention , materials that can be used for background layer 12 and legend layer 10 include those materials used in certain preformed pavement marking products of the prior art and sold by the assignee herein under the trademark “ hotape .” such materials are durable , semi - flexible pre - cut pieces of pre - formed thermoplastic . the shapes of either the background layer 12 or the legend layer 10 can be alphanumeric or geometric . the thickness of either the background layer 12 or the legend layer 10 may range from about 60 mils to about 125 mils . the thickness of the two layers can be either the same or different , depending upon the needs of a particular installation . the surface area sizes of either the background layer 12 or the legend layer 10 may vary at the option of the user . the composition of either the background layer 12 or the legend layer 10 may comprise calcium carbonate filler in the amount of about 60 - 85 wt % and preferably about 70 - 80 wt %; a first thermoplastic resin such as an alkyd resin in the amount of about 7 - 15 wt % and preferably about 8 - 10 wt %; a second thermoplastic resin such as polyamide resin in the amount of about 5 - 10 wt % and preferably about 6 - 8 wt %; plasticizer in the amount of about 3 - 8 wt % and preferably about 4 - 6 wt %; cullets dropped on the top surface in the amount of about 1 . 5 - 5 wt % and preferably about 2 - 4 wt %; paraffin wax in the amount of about 1 - 4 wt % and preferably about 1 . 5 - 2 . 5 wt %; anti - oxidant in the amount of less than about 2 wt % and preferably less than about 1 wt % and pigment in the amount of less than about 5 wt % and preferably less than about 2 wt %. the composition of either the background layer 12 or the legend layer 10 may comprise other materials that can serve as equivalents for those listed above . suitable equivalents for the calcium carbonate filler material include talc , mica , barytes , fiberglass , glass beads , and cullets , all either alone or in any combination with or without calcium carbonate , and with one or more additives , suspending agents , thickeners , or extenders . suitable equivalents for the alkyd resin include hydro resins , polyester resins , maleic resins , phenolic resins , epoxy resins , or acrylic resins and combinations thereof . suitable equivalents for the polyamide resin include ethylene vinyl acetate resin , propylene vinyl acetate resin , and polystyrene . suitable equivalents for paraffin wax include polyethylene wax and polypropylene wax , and combinations thereof . other ingredients such as leveling agents , anti - corrosion agents and uv stabilizers can also be used . the installation of both background layer 12 and legend layer 10 are described by the assignee in the brochure entitled “ application of hottape precut symbols and legends ”. as described therein , the area where the marking system is to be applied is measured and marked . the thermoplastic material is laid out on the pavement surface in the desired final position and outlined with chalk . the thermoplastic material is removed , and the pavement area within the chalk outline is heated . the thermoplastic material is placed on the heated pavement surface , and fused into place . the installation of both background layer 12 and legend layer 10 may also be accomplished with the use of a suitable adhesive or the like . various modifications of the foregoing preferred embodiments will be apparent to those skilled in the art of thermoplastic pavement marking materials . such modifications will be within the specified scope of the invention , as defined in the claims appended hereto .