Hot melt road marking paint utilizes the thermoplastic properties of synthetic resin, allowing the hot melt paint to dry quickly. The thermoplasticity of synthetic resin ensures a strong bond between the markings and the road surface. Hot melt reflective road marking paint generally consists of thermoplastic resin, pigments, reflective materials, and other additives. Hot melt paint has advantages such as good adhesion, long wear life, strong nighttime reflectivity, quick drying during construction, and good weather/water resistance, as well as being low-cost, affordable, and environmentally friendly.

     Hot melt paint is in powder form at room temperature. There are no solvent volatile components in the formulation. Heating during construction melts it, and then it is applied to the surface using specialized equipment, relying on physical cooling to solidify into a film. The thickness of the marking line coated with hot melt paint is (1.0~2.5)mm, with reflective glass beads mixed in the paint, and reflective glass beads are sprinkled on the surface during the marking process. This type of marking has good nighttime reflectivity and a long service life. Based on the traffic flow, the demand for various road marking paints in highway construction can generally reach 2-3 years.

Hot melt marking paint is a solid powder at room temperature. During construction, the paint is placed into a melting kettle, with the temperature controlled between 180℃ and 210℃, stirring while melting. Once it reaches a molten flowing state, it is placed into the insulated melting hopper of the marking machine. The molten paint is then introduced into the marking hopper and kept warm to maintain its molten state. Before marking, a pre-marking machine marks the position, and a primer machine applies the primer to the designated coating position according to the design drawing. After the primer is completely dry, the marking paint can be applied. When starting to mark, the marking hopper should be placed on the road surface. Due to a certain gap between the marking hopper and the ground, as the marking machine moves forward, a neat marking line is scraped out by automatic flow. The glass bead dispenser can automatically and evenly sprinkle a layer of reflective glass beads on the marking.

Key points for hot melt paint road surface construction:

　　1. When dissolving the paint, the temperature should be limited between 180-220. After dissolving, stir slowly and keep warm for 3-5 minutes before discharging, which can fully utilize the function of hot melt road marking paint.

　　2. It is recommended to carry out construction at temperatures above 0, ensuring the working surface is clean and dry (for high-temperature construction, please appropriately increase the material temperature).

　　3. Leave some margin for the primer treatment, and only apply the marking paint after the primer is completely dry.

　　4. For newly completed cement surfaces, please try to postpone construction for three months or stop after two primer treatments; otherwise, the markings may easily fall off.

　　5. When constructing on roads with heavy traffic, after applying the primer, please place warning cones to prevent wheels from crushing and removing the primer, leaving dust.

　　If the material temperature is below 180, the petroleum resin cannot stretch sufficiently, affecting the fluidity of the paint. During construction, the marking may become fuzzy, with numbness appearing directly on the outside of the marking, or more residue remaining, affecting the appearance of the marking. At the same time, too low a temperature will affect the extension of petroleum resin molecules, weakening the adhesion of the marking to the road surface.

　　The reasons for the slow drying of hot melt paint markings are as follows:

　　1. The standard specified environmental temperature is 23; the drying time for hot melt marking paint at 23 degrees is less than 3 minutes. If the environmental temperature exceeds this, the drying time will correspondingly increase.

　　2. If the road surface temperature is high, after the marking is completed, due to the high road surface temperature, the temperature of the asphalt road surface in summer exceeds 60 degrees. After the temperature of the hot line marking drops to the same temperature as the sidewalk, it will no longer cool down, and the marking will no longer dry. This phenomenon usually occurs during the day (around 11 am to 4 pm), especially severe for the double yellow lines in the middle of the road, as the middle of the road has a long exposure time to sunlight, resulting in slow heat dissipation.

　　3. The density of the marking paint itself is a problem; excessive use of leveling agents and other additives will improve leveling but reduce the cost of the paint. The softening point of the marking paint is also lowered, causing the hot melt marking paint to gradually dry and become soft.