High-intensity led UV curing and surface marking system for indoor and off-highway application

Abstract

A surface marking system (1) for applying and UV curing a coating layer on a road or surface, the system comprising a paint applicator (6) an LED UV light source (4) and a power supply (3) where the s

Description

The present invention relates to a mobile high-intensity LED UV curing and surface marking system specifically designed for the application and curing of high-performance coatings in off-highway or non-public road markings, primarily for indoor and private environments. Indoor line markings are applied in indoor environments, such as warehouses, logistic centers and private company areas. Typical surfaces where the line markings are applied include concrete, pavement tiling and industrial flooring. UV curing technology has traditionally been confined to highly controlled environments, such as industrial settings, where application conditions can be tightly managed. The benefits of UV curing, including rapid curing times, enhanced durability and low environmental impact due to reduced volatile organic compounds (VOCs), make it an attractive option for various industries, especially for indoor applications where minimizing downtime is of great importance. However, extending UV curing technology to the field of line marking, presents significant challenges related to mobile application in uncontrolled environments. Taking UV application outside of a confined environment has limited the broader use of this technology, particularly in the field of line marking. Nevertheless, the line marking industry for warehouses and logistic centers, could greatly benefit from UV coatings. Currently, the few attempts to deploy UV coatings for line marking in the field face significant limitations. For instance, some indoor UV line marking applications still rely on manual rolling techniques, leading to inconsistent coverage and resulting in a high rate of application failures due to inadequate curing. These methods do not leverage the full potential of UV curing technology and often result in subpar performance, affecting durability, adhesion, and overall effectiveness under demanding conditions. Contrary to road markings, line markings in indoor environments such as warehouses, need to have markings that are both strong and applied in thin layers. Due to the impact and abrasion from e.g. forklift wheels and heavy machinery, excessively thick line markings (those thicker than approximately 300 micrometers) are not preferable. Thick coatings can become more susceptible to damage. The challenge, therefore, lies in achieving a strong, thin, yet wear-resistant layer that can withstand the demanding conditions of indoor industrial settings. Current UV indoor line marking systems present several problems. They typically require manual application methods such as rolling or brushing. This manual application is not only labor-intensive but also results in inconsistent layer thicknesses. Operators find it difficult to control the coating thickness accurately when applying by hand, especially when aiming for thin layers with minimal margin for error. This inconsistency often leads to curing failures due to uneven application and insufficient UV penetration, compromising the durability and adhesion of the markings. Moreover, known UV curing systems for indoor markings are limited in the thickness of the resin paint layer that can be effectively cured, generally up to about 100 micrometers per layer or coat. Achieving uniform thin layers within this limited thickness range is challenging with manual application methods. The inability to consistently control layer thickness increases the risk of under-cured areas, leading to subpar performance and reduced wear resistance. Current systems often rely on curing units with either conventional UV light sources or LED UV light sources, each with notable limitations. Conventional UV light sources, such as medium-pressure mercury vapor light sources and gallium-doped light sources, emit light over a broader spectrum which may support thicker layer curing; however, these light sources require frequent cooling intervals, slowing down the overall curing process. They are also more sensitive to shocks and vibrations, leading to increased maintenance and susceptibility to damage during transport. Additionally, conventional UV light sources have higher energy demands and require regular bulb replacements, making them less suitable for efficient, fully mobile indoor applications. Alternatively, LED UV systems used in some indoor applications allow for more consistent curing but require significantly slower movement speeds due their lower intensity or small surface dwelling over the paint. Having lower intensity LED UV light sources or a smaller surface dwelling over the paint to ensure adequate curing of the coatings, limits the efficiency of this application. Furthermore, both conventional UV and LED UV curing systems currently used typically rely on being plugged into an electric outlet, restricting operators' mobility and range due to the electric cord, which hinders practical use in larger indoor spaces. These limitations highlight the need for an advanced solution to address the challenges of durability, mobility, and efficiency in indoor UV line marking. Currently, there are systems capable of curing coating layers exceeding 100-200 microns in thickness; however, they achieve this by incorporating glass beads, which are either partially or fully embedded within the coating layer. These glass beads facilitate curing by creating an excimer-like effect that helps extend UV penetration depth, allowing for full curing of thicker layers that would otherwise be challenging to achieve. This reliance on glass beads to reach sufficient curing depth limits the flexibility of these systems, particularly in contexts where beads are impractical or undesired. While glass beads are essential in outdoor road marking applications—primarily for retroreflectivity on highways to improve night-time visibility—these beads are typically unnecessary and rarely used in off-highway or indoor settings. Indoor environments, such as warehouses, logistic centers, and private parking facilities, do not require the reflective properties provided by glass beads, which are primarily needed to ensure safety for nighttime vehicle navigation. Consequently, for these indoor applications, systems that rely on glass beads for effective curing may present added costs, logistical complexity, and reduced functionality without delivering relevant benefits. A challenge in known systems arises from the difficulty of curing coatings that contain higher levels of pigmentation, as these pigments, such as titanium dioxide (TiO2), are essential to achieve the necessary opacity and visual contrast in indoor settings. In applications where thin layers are preferred, such as warehouses or private parking areas, coatings must have sufficient pigmentation to provide clear, high-contrast line markings that are easily visible to operators and pedestrians. However, the presence of these pigments creates a technical obstacle, as they absorb and scatter UV light, which complicates the curing process, particularly in pigmented coatings where a full cure is essential for durability. Higher concentrations of pigments, such as TiO2 at 5-20 weight percent, contribute to optimal opacity and brightness in the marking system but pose challenges for UV penetration. Titanium dioxide, often used as a white pigment, strongly absorbs UV light below approximately 380 nm, which restricts the depth to which UV light can penetrate, potentially leaving the coating incompletely cured. This effect is compounded by other pigments, like yellow, which also fully absorb UV light within the standard LED UV curing wavelengths, further preventing light from reaching lower layers. Consequently, systems designed for these applications require stronger UV light sources to ensure sufficient light penetration, allowing for a complete cure despite the higher pigment load. This balance is critical to achieve the visual contrast and durability necessary for effective indoor line marking applications. US10822755B1 (Strouds) discloses a ground surface marker comprising a paint applicator, a dispenser associated with reflectors, and a UV light source. The marker is characterised in that it can move or be moved across a ground surface so that as it moves the applicator applies paint to the surface, the dispenser causes the reflectors to contact the paint so that at least some are partially embedded in the paint and some are fully embedded in the paint, at least some of the partially embedded reflectors contacting some of the fully embedded reflectors; and the LED light source applies UV light to the paint and reflectors so that the UV light refracts through the reflectors and into the paint to dry the paint so that the reflectors are fixed in the paint and are able to reflect visible light. US10822755B1 further discloses that the UV light has a wavelength in the range of about 365 to 430 nanometres, optionally in the range of about 345 to 410 nanometres, optionally of about 405 nanometres. US10822755B1 further discloses that the marker is suitable for applying paint to a ground surface to have film thickness of about 175 to about 350 pm when dry, optionally about 175 to about 300 pm, optionally about 175 to about 250 pm. WO2021020975A1 (Damar) discloses a road marking paint composition for painting a coating of a thickness up to 400 pm when cured, on a road substrate adapted for accelerated cure by exposure to UV light, the composition comprising optically transmissive materials. The UV light has a wavelength in the range of about 365 to 405 nanometres. The LED light source generates about 1.2 to 1.8 W / cm2 The paint composition comprises about 5 to 13% by weight titanium dioxide. EP0915136A1 (Showa Denko) discloses a road marking composition for application of a coating up to 400 pm thickness and capable of being photocured within a short time. WO2008141743A1 (Hexion) discloses a paint composition for road marking curable with light energy in a short time with a good flexibility, adhesion on the road surface and with a well-preserved reflectance after traffic exposure. The purpose of the present invention is to provide a solution to one or more of the aforementioned and other disadvantages. To this end the invention concerns, in a first aspect, a surface marking system for the application and UV curing of a coating layer on a road or surface, the system comprising a paint applicator, an LED UV light source and a power supply, whereby the system is movable over a road or surface, and the system is configured such that as it moves, the paint applicator applies a coating layer of UV paint on the road or surface, and the LED UV light source cures the coating layer, whereby the LED UV light source is configured to emit UV light with a wavelength in the range of 365 nM - 495 nm, preferably in the range of 365 nM - 405 nM, characterised in that the LED UV light source has an irradiance of at least 1900 mW / cm2, and is configured to deliver an energy dose of at least 2500 mJ / cm2, wherein a fully electric battery power supply provides a power of at least 2000 W, whereby the LED UV light source is configured to cure a coating layer having a thickness of up to 400 pm in a single pass. The surface marking system is a fully electric, battery-driven mobile marking system for the application and UV curing of a UV coating layer on indoor or off-highway surfaces. The system comprises an electric battery-driven mobile unit as a power source, which includes a paint applicator, an LED UV light source, and a power supply, all integrated to ensure effective mobility across a surface. The system is configured such that, as it moves, the paint applicator applies a coating layer of UV-curable paint onto the surface, immediately followed by the LED UV light source curing the applied coating layer. Optionally the LED UV light source is on a separate electric battery-driven mobile unit. The LED UV light source is designed to emit light within a wavelength range of 365 nm to 495 nm, with a preferred range of 365 nm to 405 nm. This configuration ensures optimal penetration and curing efficiency, particularly on pigmented coatings. The LED UV light source is characterized by an irradiance of at least 1900 mW / cm2, achieving an energy dose of at least 2500 mJ / cm2. This high irradiance level allows the LED UV light source to cure indoor coating layers up to 400 pm in a single pass without requiring the addition of embedded glass beads, thus enabling a robust yet thin layer application ideal for indoor settings. The system’s power supplies integrated with the mobile unit, provides a minimum power output of at least 2000 W per battery. In one embodiment the LED UV light source has an irradiance of at least 2000 mW / cm2 and up to 16000 mW / cm2 This battery-driven configuration enables fully mobile operation within indoor and off-highway environments without reliance on external power sources, providing operators with a cord-free, maneuverable solution adaptable to a variety of surface types and applications. In one embodiment of a surface marking system of the invention the LED UV light source is configured to cure or gel a UV adhesion primer having a thickness of 0-200 pm in a single pass, the coating layer comprising a concentration of pigment of 0-10% by weight, preferably 0-4% by weight. In another embodiment of a surface marking system of the invention the LED UV light source is configured to cure or gel a UV base coat having a thickness of 0-400 pm in a single pass, the coating layer comprising a concentration of pigment of 0-10% by weight, preferably 5-8% by weight. In another embodiment of a surface marking system of the invention the LED UV light source is configured to cure or gel a UV top coat having a thickness of 50-250 pm in a single pass, the coating layer comprising a concentration of pigment of 0-10% by weight, preferably 0-5% by weight. In yet another embodiment of a surface marking system of the invention the coating layer comprises a clear coat which is clear of pigment (0%). The above surface marking system is specifically related to indoor surfaces such as warehouse floors, logistic centers, and thinner layers for private parkings or airports. The present invention provides a UV curing and mobile surface marking system that meets the rigorous demands of both indoor and outdoor applications. The system is engineered to deliver higher-intensity UV curing in a more controlled and safe manner, enabling the application and curing of some UV coatings up to 400 pm thick in a single-layer application, i.e., in a one pass. The line marking industry, encompassing indoor settings requires a robust solution capable of high-intensity UV curing under varied and often harsh conditions while ensuring operator safety and compliance with high safety standards. This invention addresses these needs. UV coatings require a high-intensity UV light to cure rapidly and fully, particularly for coatings applied in thin layers. The invention addresses these challenges by incorporating high-intensity UV light sources into a cordless mobile unit capable of curing UV coatings up to 400 pm thick. The invention introduces a differentiation between coatings with varying purposes, such as UV adhesion primers for different surfaces, base coats and top coats, and varying pigment levels. Current UV line marking coatings containing more than 5% by weight titanium dioxide (TiO2) provide the necessary opacity required for safety and visibility. Although these coatings are more challenging to cure due to their high pigment concentration obstructing UV penetration, the system's high-intensity light sources efficiently overcome this obstacle, enabling effective curing regardless of the coating thickness. This allows for compliance with safety standards while optimizing curing efficiency. The system is capable of UV curing or gelling these coatings at thicknesses up to 400 pm and application speeds of up to 3 km / h, representing a significant advancement in UV curing technology, allowing for more efficiency, consistency and lower rate of failure. An advantage of the present invention is that curing is performed without the requirement for glass beads in the paint / coating layer to be cured effectively. This system provides a robust, efficient, and environmentally friendly solution for modem line marking, capable of meeting stringent durability and visibility requirements even under challenging and uncontrolled conditions. The system represents a comprehensive and highly technical solution for modern line markings, that integrates higher-intensity UV curing technology with advanced power management, temperature, speed control and robust safety features in a mobile platform. The present invention further distinguishes from known systems by overcoming the above challenges through the integration of high-intensity UV light sources (more than 2000 mW / cm2, typically between 2000 mW / cm2 and 6000 mW / cm2) scalable power systems (to ensure stronger light sources can be used, resulting in longer dwell time and higher intensity to get deeper into the coating), and advanced temperature control mechanisms (heated hoses, and heated tanks) within an electric battery driven mobile application. These features enable the effective curing of thicker coatings, at better application speeds in a more consistent way. More specifically, the system of the present invention overcomes the challenges associated with known systems by integrating higher-intensity LED UV light sources exceeding 2000 mW / cm2, typically ranging from 2500 mW / cm2 to 6000 mW / cm2. It incorporates scalable power systems that support the use of longer and stronger light sources, resulting in longer dwell times and higher UV intensities, which enable deeper penetration into the coating for effective curing. Additionally, advanced temperature control mechanisms, such as heated hoses and optional heated tanks, are provided within a mobile optionally speed-controlled cordless application system. These features facilitate the effective application and curing of thicker UV indoor line marking coatings, including optionally highly pigmented coatings, at improved application speeds with greater consistency. Due to the limitations of weaker or smaller UV light sources, existing UV surface curing systems are constrained to applying coatings with an estimated maximum thickness of approximately 150 pm with 5-20% by weight pigments at application speeds of 0.5-1.5 km / h. In contrast, the system of the present invention employs larger, higher-intensity UV light sources and scalable power systems, enabling the application and effective curing of coatings up to 400 pm thick at speeds ranging from 1.5 to 5 km / h. Specifically, for coatings comprising 2-8% by weight titanium dioxide, the invention can cure coatings up to 400 pm thickness at speeds of 2-3 km / h on mobile units. This represents a significant advancement over known systems, particularly in the ability to cure thicker, highly pigmented coatings at more efficient application speeds. UV curing is a process in which ultraviolet (UV) light initiates a photochemical reaction that cures or hardens a material, such as coatings, inks, or adhesives. The effectiveness of this process depends on several factors related to the UV light, including UV irradiance (intensity), energy dose (the total energy delivered per unit area), and spectral distribution (wavelengths). While infrared radiation does not initiate curing, it can affect the process by causing heating, which may influence the material properties during curing For the purposes of this invention, the terms UV light, UV light source and UV light source are used interchangeably in the application and refer to ultraviolet light-emitting devices used for curing. The total power output of a light source is measured in watts (W); however, the UV radiant power is the portion of this total power that is emitted as ultraviolet radiation relevant to the curing process. The terms UV paint (composition) or layer of UV paint refer to a coating or marking that is cured by exposure to UV energy. This material typically comprises a combination of photo initiators, oligomers, monomers, and pigments for color. The material is applied to a substrate prior to curing. The term substrate or (ground) surface means the physical media that the coating is applied to and adheres to once cured. In this application, this is typically a road, flooring, concrete or the like. UV irradiance (intensity) is defined as the radiant power incident on a surface per unit area, measured in watts per square centimeter (W / cm2). Higher irradiance ensures that sufficient energy penetrates deeper into thicker coatings. Consequently, the greater the irradiance at the surface, the more energy is available to effectively cure the deeper layers of the material. Peak irradiance represents the maximum irradiance level at the surface. An increased peak irradiance enhances curing efficiency, particularly for thicker or more opaque materials, by delivering a higher intensity of UV light where it is most needed. The UV energy dose is the total accumulated UV energy incident on a surface, typically measured in joules per square centimeter (J / cm2). This dose corresponds to the total energy delivered per unit area during a defined exposure period, known as the dwell time. Mathematically, the dose is calculated by multiplying the irradiance by the dwell time (Dose = irradiance x dwell time). Dwell time (in seconds) refers to the duration for which the substrate is exposed to UV energy. Dwell time is influenced by the substrate's speed relative to the UV source and the size of the emitting window (the length of the UV exposure area in the direction of movement). For instance, a material moving at 50m / min and exposed to a 20 mm wide UV light source will have the same dwell time as a material moving at 100m / min exposed to a 40 mm wide UV light source. In both scenarios, the dwell time is calculated as the exposure width divided by the substrate speed: For thicker coatings, high UV irradiance ensures that sufficient energy penetrates through the entire thickness of the material, enabling effective curing of both the surface and deeper layers. Spectral distribution refers to the range of UV wavelengths emitted by the LED UV light source, measured in nanometers (nm). Different materials have specific absorption spectra, absorbing UV light differently across various wavelengths. Optimizing the spectral output of the UV light to match the material's absorption characteristics enhances the curing process by maximizing energy absorption where it is most effective The intensity of the UV light significantly impacts penetration depth in thicker coatings. Thicker coatings require increased UV energy to reach and cure the deeper layers. High irradiance ensures that sufficient energy passes through the top layers of the coating, reaching the bottom layers without being excessively absorbed or scattered. Curing efficiency in UV curing processes is a significant challenge, particularly for thicker or more opaque materials. It is highly dependent on the peak irradiance, the maximum UV light intensity at the material's surface. High peak irradiance enhances curing efficiency by providing sufficient energy to penetrate deeper into the coating, ensuring a full cure throughout the entire thickness (through-cure), which results in improved adhesion and durability. While dwell time (the duration of exposure) plays a role, curing efficiency is not solely dependent on it. Factors such as irradiance intensity, spectral distribution and the material's absorption characteristics also critically influence the curing process. By utilizing high peak irradiance, the system can achieve effective curing more efficiently, potentially reducing the required dwell time and optimizing the total energy used for curing. Avoiding incomplete curing is a significant challenge. In thicker coatings, deeper layers may remain uncured if the UV light does not provide sufficient irradiance. This can lead to poor adhesion, surface tackiness, and compromised durability of the cured material (e.g. failed application). Mobile surface marking units typically face limitations concerning energy supply. The challenge is to find a balance between light source intensity (irradiance in mW / cm2), exposure time (dwell time), and coating thickness, all while managing a limited energy draw. This is illustrated in the following example. To achieve a total energy dose of 1000 millijoules per square centimeter (mJ / cm2) on a coating moving at a speed of 20 millimeters per second (mm / s) under an LED UV light source two scenarios are exemplified. In a first scenario, the LED UV light source has an illumination area - the length of the LED UV exposure section - of 20 millimeters. This means each portion of the coating spends 1 second under the LED UV light. This exposure time is calculated by dividing the illumination area by the speed (20 mm divided by 20 mm / s equals 1 second). Using an LED UV light source with an irradiance (intensity) of 1000 milliwatts per square centimeter (mW / cm2), the energy dose received by the coating is determined by multiplying the irradiance by the exposure time. Therefore, the coating receives a total energy dose of 1000 mW / cm2 multiplied by 1 second, resulting in 1000 mJ / cm2. In a second scenario, a more powerful LED UV light source with a higher irradiance of 4000 mW / cm2 but a smaller illumination area of 5 millimeters is used. Each portion of the coating spends only 0.25 seconds under the LED UV light (5 mm divided by 20 mm / s equals 0.25 seconds). Despite the shorter exposure time, the energy dose received is still 1000 mJ / cm2, calculated by multiplying the irradiance (4000 mW / cm2) by the exposure time (0.25 seconds). In both scenarios, the total energy dose delivered to the coating is the same, 1000 mJ / cm2. However, the higher peak irradiance in the second scenario leads to better curing performance, especially for thicker coatings. The increased intensity of the UV light enhances penetration into deeper layers of the material, improving the likelihood of achieving a complete cure. Another example highlights the impact of irradiance and exposure time on the energy dose. A powerful UV light source operating at an irradiance of 1000mW / cm2 for 1 second delivers a dose of 1000mJ / cm2. In contrast, a weaker UV light source with an irradiance of 100mW / cm2 would need to operate for 10 seconds to deliver the same total energy dose. Despite both scenarios providing the same total energy dose, the higher irradiance from the powerful light source results in more effective curing, particularly for thicker or more opaque materials. This is because higher irradiance over shorter exposure times enhances energy penetration and reduces the likelihood of incomplete curing in deeper layers, leading to better adhesion, durability, and overall performance of the cured material. The present invention supports multiple light source configurations tailored to the specific requirements of both indoor and outdoor applications. The flexibility of these configurations allows the system to adapt to a wide range of line marking projects. For example, indoor applications may utilize smaller light sources optimized for higher intensity suitable for smaller or slower mobile units, while outdoor applications may employ larger light sources capable of covering broader areas at higher speeds with increased energy capacity. The integrated LED UV light sources are designed to achieve optimal curing of thick and pigmented coatings for visible line marking applications requiring high opacity. This system incorporates both high energy (measured in J / cm2) and high-intensity (measured in W / cm2) in the curing process, particularly when applying thicker coatings. Energy and intensity are two interrelated factors that work together to achieve thorough curing, ensuring that the entire coating, especially thicker layers, receives sufficient exposure to initiate and complete the curing process. Energy, or UV dosage, represents the total accumulated photon quantity that reaches the surface and is directly related to the dwell time under the LED UV light source. For indoor / off-highway UV coating applications, where pigmented coatings in the line marking industry can easily exceed 100 pm in thickness, intensity becomes a paramount factor. High-intensity, defined as the radiant power arriving at a surface per unit area, ensures that sufficient energy penetrates through the top layers of the coating to reach the deeper layers. This is particularly important because, as UV light penetrates a coating, its power diminishes due to absorption and scattering. According to the Beer-Lambert law, higher surface intensity leads to greater energy availability at deeper layers, making it possible to cure thick films effectively. Moreover, higher intensity not only accelerates the polymerization process but also improves the durability of the system by completing a full cure. High-intensity curing with the right wavelengths helps to overcome issues such as surface tackiness, deep cure failures and oxygen inhibition, which are common challenges in UV curing. By rapidly initiating the curing process, high-intensity mitigates these issues and ensures a more uniform and durable cure throughout the coating. Higher-intensity UV flood light sources on a mobile platform, particularly those operating at levels above 2000 mW / cm2, require substantial energy to function effectively. Despite advancements in LED UV technology, these high-intensity light sources still demand significant power supplies. Traditional mobile systems are typically constrained by their energy sources, such as standard engines on mobile units or battery-driven units, which are insufficient to support the operation of powerful LED UV light sources. The invention addresses these limitations by incorporating an innovative energy battery supply system, enabling even smaller mobile units to reliably power LED UV flood curing light sources at intensities exceeding 2000mW / cm2. This capability allows for the integration of higher-intensity UV light sources into various configurations, optimizing the curing process for different applications. The LED UV curing light sources integrated into this invention are designed in various configurations, each tailored to meet the specific demands of different applications. Depending on the intended use — whether for indoor environments like warehouses or off-highway road marking like airports or private parkings — these light sources are designed to address the unique requirements associated with each scenario. For instance, indoor applications may prioritize precise, controlled curing over smaller areas, often requiring thinner coatings and lower curing speeds. In contrast, off-highway applications typically require faster application, with thicker coatings and higher-speed processes, demanding more robust and powerful light source configurations. The invention offers a range of LED UV light source configurations with varying intensities and widths, enabling optimal curing performance across all types of applications. The system can be adjusted to match the specific curing requirements of the application. By incorporating these versatile light source options, the invention ensures that the curing process is consistently effective, regardless of the application’s thickness speed, or changing environmental conditions we experience for this type of UV application. This adaptability allows for the most efficient use of energy and resources while delivering more consistent application and curing results in both indoor and outdoor UV curing applications. To effectively cure material layers exceeding 400 pm in thickness, the invention provides various UV light source configurations designed to deliver both extended dwell time and high irradiance. The extended dwell time—the duration during which the LED UV light source remains over the coating—ensures sufficient exposure for thorough curing. Simultaneously, the high irradiance facilitates deeper penetration of UV energy into the coating, overcoming absorption losses and enabling complete curing of thick layers. In one embodiment of a surface marking system of the invention the LED UV light source is a high-intensity flood LED UV light source with a uniform irradiance. The configuration features an LED UV curing light source with an optimized surface area designed to maximize dwell time and ensure thorough curing, particularly when treating larger surfaces. Unlike smaller high-intensity LED UV light sources, these flood light sources are engineered to deliver consistent irradiance across the entire coverage area, ensuring uniform curing without compromising on application speed or quality. The size and width of these flood light sources are customizable to match the specific requirements of different mobile units. This flexibility allows for the optimization of curing performance based on the energy capacity available on the unit in relationship to the output of the paint on the unit. Typically, for indoor applications, these light sources are designed to be around 150mm wide and up to 250mm long, providing sufficient energy for indoor environments and applications needs. For outdoor use, where larger surface areas, faster application speeds and thicker coating thicknesses are required for greater durability, the LED UV light sources can be designed with widths ranging from 150 mm to 550mm. Outdoor light sources may typically have lengths from 300 mm up to 1000 mm, depending on the size of mobile unit to accommodate the broader, more demanding applications typical in road marking The flood LED UV light source operates with a uniform irradiance typically ranging from 2000mW / cm2 to 6000mW / cm2 making the light source highly effective for consistent curing across large surfaces. The consistent output ensures that the curing process is not only reliable but also optimized for speed, allowing for faster processing times without sacrificing the quality of the cure. In a specific embodiment the LED UV light source is configured to emit a uniform irradiance ranging from 2000mW / cm2 to 4000 mW / cm2 in air-cooled configurations and from 3000 mW / cm2 to 6000 mW / cm2 in water-cooled configurations. In terms of wavelength, the LED UV light source operates within a range of 365nM to 495nm, with 405nm typically the most commonly used wavelength. This range is carefully selected to ensure effective penetration and curing depth, particularly important for applications requiring deeper curing layers. The flood light source is typically air-cooled, which helps maintain optimal operating temperatures and prevents overheating, which could otherwise compromise the performance and longevity of the light sources. Alternatively the LED UV light source uses water cooling, typically on bigger mobile units outdoors to minimize dust intake on the road. The energy consumption of the higher-intensity LED UV light sources of the invention typically ranges from 2000W to 10,000W, depending on the size and intensity required for specific applications. For units requiring more than 4000 watts, the system distributes the energy across multiple power supplies, each capable of providing up to 4000 watts. This distribution ensures that the light sources receive a stable and adequate power supply while enhancing the flexibility and scalability of the system, allowing it to adapt to different mobile units and curing requirements. This configuration, with its robust design and adaptable features, makes traditional flood LED UV light sources the most commonly used option in this invention, providing a reliable and efficient solution for a wide range of UV curing applications. In one embodiment the flood LED UV light source is provided with a uniform irradiance of 2000 mW / cm2 and higher. By way of example a small walk behind mobile unit system may comprise an air-cooled uniform LED UV flood light, 250mm long and 150mm wide, having a wavelength of 405nM and an intensity of 3000 mW / cm2 at 30mm distance. The energy needed for this system is 2400W (at 80% strength), supplied by the engine and supported by a supplementary 2400W battery. In another embodiment of a surface marking system of the invention the LED UV light source comprises multiple UV sections having a different irradiance and / or wavelength. The UV sections are typically configured widthwise, whereby a specific section covers the full width of the light source, but only part of the length. The sum of the length of the sections corresponds to the length of the LED UV light source unit. In one embodiment the sections comprise a different irradiance and an identical wavelength. In another embodiment the sections comprise a different wavelength and an identical irradiance. Yet in another embodiment the sections comprise a different wavelength and a different irradiance. In a specific embodiment of a surface marking system of the invention an LED UV light source is provided comprising multiple sections, with a higher intensity section typically configured near the front of the light source, and a lower intensity section near the back of the light source. As such the higher intensity UV section cures the coating first, followed by the lower intensity UV section. Hereby the mobile unit uses an LED UV configuration that builds upon the traditional flood lights described previously, introducing an additional feature to address specific curing challenges associated with thicker or more heavily pigmented coatings. The enhanced flood lights maintain the same foundational design, providing uniform coverage across the application area. However, they incorporate a specialized higher-intensity section, typically located at the beginning of the lighted area, that is the section of the light source that hits the line marking first. The flood LED UV light source comprises one irradiance surface (flood light), but in a combination that provides different strengths. The combination e.g. can be a flood light source with a higher-intensity light source at the front of the light source, or a flood light source divided in at least two significantly different sections of strength. These two sections provide a long dwell time and a higher peak. The UV sections are preferably provided in a single housing. In one embodiment the LED UV light source comprises one or more LED components. The highest intensity and / or highest wavelength section is provided typically near the front of the LED UV light source, compared to the driving / application direction of the mobile unit. In other words, the higher intensity section of the LED UV light source reaches the coating first. As such a coating is first cured at a higher intensity and / or wavelength, and thereafter at a lower intensity or wavelength. The lower-intensity section is typically configured at the back of the light source. The higher intensity section provides an additional irradiance boost, with intensities ranging from 5000mW / cm2 up to 16000mW / cm2. This increased intensity is supporting improved photochemical reactions within the coating are completed efficiently and thoroughly, particularly in areas where standard irradiance levels may not penetrate sufficiently to achieve a full cure. The lower intenstiy section provides intensities ranging from 2000 mW / cm2 up to 3000 mW / cm2 The UV sections have a higher wavelength in the range of 405 nm and a lower wavelength in the range of 365 nm. In one embodiment of a surface marking system of the invention, the LED UV light source comprises a UV floodlight with an intensity of 2000-6000mW / cm2, preferably 2500-4000mW / cm2, and a more focused UV light source with a high-intensity of 5000-16000mW / cm2, preferably 5000-8000mW / cm2. Both the main flood section and the high-intensity section can be configured independently, with adjustable intensity settings ranging from 0 to 100% of their maximum output. This flexibility allows the system to optimize energy usage by tailoring the light intensity to match the specific requirements of the coating thickness and material properties. For example, thinner layers or transparent coating (such as transparent primers and top coatings) require only moderate intensities, while thicker or more complex coatings would benefit from the maximum available power. The size of these light sources can be customized to match the mobile unit’s capabilities, with typical dimensions ranging from 150mm wide and up to 250mm long for indoor use, and from 175mm to 1000mm long for outdoor applications. Energy consumption varies depending on the application, with the high-intensity sections requiring more power. For systems exceeding 3600 watts, energy distribution is managed across multiple power supplies, ensuring stable and efficient operation. This enhanced configuration is particularly advantageous in applications where achieving a deep, thorough cure is critical, such as in high-traffic road markings or other demanding applications, such as higly pigmented coatings and faster application speeds. By providing an extra boost of intensity exactly where it is needed, these light sources ensure that even the more challenging UV coating applications are fully cured, enhancing the durability and effectiveness of the applied markings. By way of example a system may comprise an air-cooled uniform LED UV flood light with one extra high-intensity section. The system comprises a traditional LED UV flood light section with a uniform intensity of 2500 mW / cm2 at 30mm from the substrate (typically between 2000 mW / cm2 and 4000 mW / cm2), 220mm long and 150 mm wide, and further an extra high-intensity section with an intensity of 5000 mW / cm2 at 30mm distance from the substrate (typically between 5000 mW / cm2 and 16000 mW / cm2), 30mm long and 200 mm wide, a wavelength of mainly 405nM and partially 365nM, two separate intensity controllers (0-100%). The highest intensity and / or wavelength section is provided typically at the front of the LED UV light source, compared to the driving / application direction of the mobile unit. In other words, higher intensity section of the LED UV light source reaches the coating first. As such a coating is first cured at a higher intensity or wavelength, and thereafter at a lower intensity or wavelength. The system requires an energy supply of 3600 watts, provided by an external battery. This battery is designed with flexibility in mind and can be recharged through multiple methods: it can be recharged via the mobile unit's engine, connected to an external electrical power source, or exchanged for a fully charged battery. This ensures continuous operation and adaptability to various working environments and logistical considerations. In a specific embodiment of the invention a double LED UV light source comprises a UV floodlight with an intensity of 2000-6000mW / cm2, preferably 2500-4000mW / cm2, and a more focused UV light source with a high-intensity of 5000-16000mW / cm2, preferably 5000-8000mW / cm2. In one embodiment the flood LED UV light source is set up as a LED board comprising multiple sections of different width and / or different length. The sections can be switched on / off as required according to the application. In a specific embodiment the flood LED UV light source is set up as a LED board comprising multiple sections of different width over the full length, wherein each section can be switched on / off for saving energy and matching a line for marking. In this way, a specific section having a specific width can be matched to a specific line width. The sections of the LED UV light source are configured lengthwise and the sum of the width of the sections equals the width of the LED UV light source, whereby “length” corresponds to the direction of application / driving and “width” corresponds to the line width. In one embodiment of a surface marking system of the invention the LED UV light source sections have a uniform irradiance and wavelength. In that case the only purpose of the zoning is energy-saving. In one embodiment the LED UV light sources are configured into sections of varying widths, optimizing energy usage based on the specific requirements of the road marking application. Road markings, whether for indoor or outdoor use, have standard line widths that vary depending on the application, local regulations, and specific project requirements. For instance, indoor applications often require line widths of 50mm or 100mm. In scenarios where the LED UV curing light source on the mobile unit has a total irradiance width of 150mm or 200mm, using the full width of the light source for a narrower 50mm line would result in significant energy loss. To address this, our UV light source controller could be equipped with a switch that enables or disables customizable sections of a certain width within the light source. For example, if the application calls for a 50mm UV paint line, and the LED UV curing light source has a 150mm irradiance width, the controller can deactivate certain sections to reduce the effective light source width to 100mm. This adjustment ensures that the entire 50mm line is cured effectively while minimizing unnecessary energy consumption. Should the same application later require a 100mm UV line, the previously disabled section can be reactivated, expanding the curing width back to 150mm and ensuring full coverage and curing of the wider line. For instance, if an application requires a 150mm line but the LED UV light source has a 300mm irradiance width, activating only 200mm of the light source’s width can reduce energy usage by approximately 33%. This allows the light source to deliver the necessary intensity across the entire 150mm line without wasting energy on areas that do not require curing. By enabling this sectioned configuration, the system significantly improves energy efficiency while maintaining the high performance and thorough curing needed for both indoor and outdoor road marking applications. In a further specific embodiment of a surface marking system of the invention the LED UV light source comprises multiple sections of different lengths over the full width whereby the sections have a different intensity and wavelength. In an example embodiment of a surface marking system of the invention the LED UV light source comprises an LED UV section with a uniform intensity and a wavelength of mainly 405nM (at the front of the LED UV light source) and partially 365nM (typically at the back of the LED UV light source), and at the front of the LED UV light source further a higher-intensity section and a wavelength of 405nM, and two separate intensity controllers (0-100%). By way of example the system may comprise an air-cooled uniform LED UV flood light with two energy saving sections. The system comprises a traditional LED UV flood light section with a uniform intensity of 3500 mW / cm2, 470mm long and 300 mm wide a wavelength of mainly 405nM (at the front of the LED UV light source) and partially 365nM (typically at the back of the LED UV light source) , and at the front of the LED UV light source further a higher-intensity section with an intensity of 6000 mW / cm2, 30mm long and 300 mm wide, a wavelength of 405nM, two separate intensity controllers (0-100%). The longer mixed wavelength LED UV flood light section is typically provided at the front of the light source (i.e. with the lowest wavelength at the back), whereas higher-intensity sections are typically located before the lower-intensity sections. The energy needed by the system is 7200W, provided by two 3600W external exchangeable batteries with optional recharging via the engine of the mobile unit. Safety is of paramount importance when working with high-intensity ultraviolet (UV) light, particularly due to the potential harm that prolonged or intense exposure can cause to human skin and eyes. UV light at the intensities used in UV curing applications can pose significant health risks if not properly managed. In most industrial settings, UV light sources—whether LED or conventional—are typically enclosed or shielded to prevent direct exposure, thereby protecting operators and nearby personnel from harmful UV radiation. By applying UV curing technology to line marking in both indoor and off-highway environments, the present invention extends UV curing applications into public and less controlled spaces, such as indoor facilities where other individuals may be present. While operators are required to use personal protective equipment (PPE), such as UV-resistant goggles and protective clothing, the risk of unintended exposure increases when UV curing is conducted in public more uncontrolled areas. Bystanders, including pedestrians, motorists, or workers adjacent to the application, may be unaware of the hazards and could inadvertently be exposed to intense UV light, especially if they are drawn to look toward the bright light source. To mitigate these risks, the invention incorporates a UV protective shroud mounted or surrounding the LED UV light source for blocking and / or filtering UV radiation. This shroud is designed to minimize the escape of harmful UV radiation to an absolute minimum, effectively filtering out UV light from escaping into the surrounding environment. The protective shroud allows the necessary UV light to reach the coating being cured while shielding operators and bystanders from both direct and reflected UV exposure as much as possible. By containing the UV radiation within the immediate curing area, this design ensures that the curing process can be carried out more safely in public or shared spaces without compromising the effectiveness of the UV curing or posing health risks to individuals in the vicinity. In one embodiment of a surface marking system of the invention the LED UV protective shroud comprises a top panel covering the LED UV light source, extending into front, back and side panels surrounding the light source and floating above the surface at 2-100 mm, preferably 5-40mm. The shroud protects operators and bystanders from potentially harmful high-intensity UV exposure. The shroud not only improves safety (no unfiltered UV light escapes into the surrounding environment) but also still allows for effectively visually monitoring of the curing process. The shroud is made of UV-filtering materials, such as polycarbonate, PET-G, or (specially treated) plexiglass, with polycarbonate being the preferred material. Polycarbonate is especially suitable for this application due to its inherent ability to filter out a significant portion of harmful UV radiation, particularly in the UV-B and UV-C ranges. It offers excellent fire-resistant properties, chemical resistance, and high optical clarity. Notably, polycarbonate is much stronger than glass of the same thickness, making it an ideal choice for situations where safety, visibility and durability are crucial. The material's optical properties ensure that visible light is effectively transmitted, allowing operators to monitor the curing process while maintaining a safe environment. By effectively filtering harmful UV radiation, the polycarbonate shroud minimizes the risk of UV exposure to operators and bystanders without impeding the performance of the UV curing process. The protective shroud can make use of clear polycarbonate UV or alternatively colored polycarbonate UV to block the light even more. The shroud is preferably made of 1 mm to 3 mm thick polycarbonate UV, providing high clarity and durability while effectively blocking UV radiation. The shroud is constructed around the LED UV light source and may include optional UV protective brushes. This design allows the light source's distance from the substrate to be adjusted as needed, with the shroud moving in unison to maintain effective UV shielding. Traditionally, mainly brushes have been used around UV lights to block stray light, but this approach presents two significant issues. Firstly, the operator still needs to visually confirm that the UV curing light is functioning, especially since they must monitor both the paint application and, optionally, the distribution of glass beads. For outdoor applications, and optionally for indoor uses, the LED UV curing unit is integrated onto the same unit as the UV paint gun and the glass bead applicator, allowing the operator to see the light and ensure that the system is working properly. Secondly, brushes cannot be brought completely to the ground at the front of the UV light where the curing process begins. If the brushes were to touch the uncured paint, they would disrupt the application, resulting in a damaged line. To address this, the invention applies a system of brushes on the sides of the UV light, with optional placement at the back and minimal length at the front. This configuration maintains a safe distance between the brushes and the uncured paint, ensuring that the application remains intact while still providing UV protection. Moreover, the shroud is designed to allow the operator to adjust the height of the UV curing light source. The adjustability allows to optimize the intensity and focus of the UV light based on the specific requirements of the application, ensuring that the curing process is both effective and safe. Temperature control is a main aspect of UV coating applications, for ensuring constant optimal performance of the coating in terms of viscosity, curing efficiency, and durability, even under variable environmental conditions. UV coatings are sensitive to temperature fluctuations, which significantly impact their viscosity and, consequently, the application process and the final properties of the cured coating. Certain components within UV paint formulations—such as photoinitiators, monomers, and oligomers—can degrade or react undesirably when exposed to temperatures above approximately 50 °C for extended periods. This thermal degradation can lead to compromised quality and durability of the coating, resulting in issues such as reduced reactivity, incomplete curing, or altered mechanical properties. Maintaining the coating material below these temperatures is therefore favourable to preserve its integrity and ensure optimal performance. The viscosity of UV coatings is directly influenced by temperature. At lower temperatures, the viscosity increases, making the coating thicker and more challenging to apply uniformly. This elevated viscosity leads to poor flow characteristics, resulting in uneven or non-uniform application. The increased resistance to flow can cause the coating to be applied inconsistently across the substrate, increasing the likelihood of applying it too thick in certain areas. Excessively thick coatings unevenly divided increase the risk of curing failures, as UV light may not penetrate sufficiently to cure the deeper layers. Incomplete curing can lead to poor adhesion, surface tackiness, and reduced durability of the coating. Maintaining the coating material within an optimal and consistent temperature range impedes the application process. Typically, this optimal temperature range is between 25 °C and 40 °C. Keeping the coating within this temperature range ensures that the viscosity remains at a level conducive to uniform application, appropriate film thickness control, and effective curing. The system is particularly well-suited for indoor applications and even colder / non heated storage facilities, where environmental conditions can vary widely. In controlled industrial environments, maintaining the appropriate temperature for UV coatings is more straightforward due to the stable ambient conditions and the availability of sophisticated temperature regulation systems. However, line marking applications, particularly those conducted outdoors, present unique challenges. The variability in environmental conditions, such as extreme heat in summer or cold in winter, can significantly impact the temperature of the coating during application. In the field of line marking, temperature control options are limited, especially for smaller mobile units. While larger trucks and more complex setups, such as two-component epoxy trucks used in some parts of the USA for example, may offer temperature control systems, smaller units often lack the necessary energy resources to implement these features. It is favourable not to heat the UV coating too intensely because certain components within UV paint formulations—such as photoinitiators, monomers, and oligomers—can degrade or react undesirably when exposed to temperatures above approximately 50 °C for extended periods. Excessive heating can lead to premature polymerization, reduced reactivity, or degradation of the coating material, compromising its quality and performance. For this reason, the system avoids using airless flow heaters, which typically operate at high temperatures and rapidly heat the coating material. Such rapid and intense heating can potentially affect the UV coating due to thermal stress. Instead, the system employs heated hoses that gradually and uniformly warm the paint throughout the delivery system. This approach maintains the coating material within the optimal temperature range, ensuring consistent viscosity when the paint reaches the spray nozzle and optionally during recirculation if applicable. The present invention addresses these challenges by incorporating a closed heated loop system consisting of a heated hose system—available for both high-pressure airless and low-pressure conventional spraying options—and, optionally, an insulated heated tank. The hose is heated for instance by means of electric heating elements that gradually heat the hose over its full length. In one embodiment of a surface marking system of the invention the system further comprises a closed loop heated hose system and optionally a heated paint tank for maintaining the paint at a constant paint temperature of 20-50 °C, typically 30-40 °C, and a consistent viscosity. The closed loop heated hose system comprises a heated paint hose running from the paint tank to the nozzle of the applicator, and optionally a heated return hose from the nozzle back to the tank. The heated paint tank is double-sided, optionally insulated, and comprises internal heating pads. The system employs heated hose assemblies where both the supply hose (typically 6 mm or 10 mm in diameter, equivalent to 1 / 4 inch or 3 / 8 inch) delivering the coating material to the application gun and, optionally, the return hose from the gun back to the tank are heated. By heating both hoses, the system ensures that the coating material maintains a consistent temperature throughout its circulation. The hoses may be wrapped with insulating material to minimize heat loss, thereby enhancing temperature stability during the application process. The length of the hoses can range from 1m to 45m, depending on the application and energy options. The heated tank may comprise a closed lid to protect the UV paint against light and air contamination. The tank wall is optionally insulated in between the inner and outer walls of the double-sided tank. A heated hose is connected to the tank for recirculation of the paint. The tank is typically made of plastic or stainless steel. The inside wall of the tank optionally has an epoxy coating to protect the wall against the chemical impact of the paint. The tank and / or hopper is heated typically by heating pads provided in the double-sided wall. Typically 1,2 or 3 pads of 200-300W each are provided for smaller units. For bigger tanks custom made solutions are provided. The tank is optionally interchangeable for fast paint (color) changes, or disposable liners are used. To manage the flow of the UV coating material when not spraying, the system incorporates back-pressure valves or manual valves. These valves allow for slow, continuous recirculation of the UV paint even when spraying is paused. Maintaining a continuous flow of the UV material is favorable because it prevents the paint from sitting stationary in the hoses, which can lead to increases in viscosity or potential overheating within the lines due to prolonged exposure to heat. Continuous flow also helps maintain a consistent temperature throughout the system, ensuring optimal viscosity for uniform application when spraying resumes. Depending on the operator's preference and specific application requirements, these valves can be operated automatically or manually. The tank design varies depending on the type of application. Additionally, the tanks can be insulated with materials such as polyurethane (PUR) to further enhance temperature retention in colder conditions. By integrating advanced temperature control mechanisms, including heated hoses and tanks, this invention ensures that UV coatings are applied at their optimal, consistent viscosity ensuring optimal curing, and overall performance. These features result in high-quality, durable road markings, particularly in the challenging and variable conditions typical of line marking applications. The ability to maintain consistent material temperature not only improves the efficiency and reliability of the coating process but also ensures that the final product meets the highest standards of durability and safety. An example of a heated hose customized insulated airless is as follows: voltage 230 V - 50 Hz, heating power 300 Watt per hose, 5m 1 / 4” airless hose, max. working pressure 250 bar, temperature control 20-100°C (stepless). An example of a heated hose standard airless is as follows: voltage 230 V - 50 Hz, heating power 1100 W, hose DN10 I 30m PU sheath, max. working pressure 250 bar, temperature control 20-60°C (stepless), weight 23kg, hose length 30m. The system integrates advanced controls to ensure precise application of UV coatings. Recognizing the importance of precision and control in UV paint applications, the system incorporates advanced control mechanisms to replicate the controlled environment typically found in industrial settings. By integrating industry-standard spraying techniques with sophisticated control systems, this mobile unit is able to deliver a consistent and high-quality finish, even in varying field conditions. This approach allows for the recreation of a controlled environment on a mobile platform, ensuring that the application process remains as close to industrial standards as possible, regardless of the application setting. The mobile unit is designed to achieve a highly consistent and controlled UV coating in the uncontrolled nature of this application. By using industry-standard spraying technologies such as airless systems (including double diaphragm airless pumps and bellow pump airless systems) or conventional pressure tank spraying with and an optional software-controlled flow meter, the system ensures that the applied layer thickness is consistently accurate. This combination not only minimizes the risk of uncured applications but also reduces the likelihood of errors, resulting in a low failure rate and a professional, industry-like finish. The system optionally comprises an electric transaxle drive (e-drive) to ensure a consistent speed during application and curing. The UV coating application process on this mobile unit utilizes industry-standard UV compatible paint spraying systems, including airless double diaphragm pumps, bellow pumps, and conventional pressure tank spraying methods. These systems are integral to the consistent application of UV coatings, as they are specifically engineered to meet the unique demands of UV coatings, providing the necessary precision and consistency for high-quality results. In this system, the use of low-shear pumps—such as airless bellow pumps with low shear packings, airless double diaphragm pumps, and conventional pressure tank spraying techniques—is advantageous for maintaining the integrity of UV paints and extending the lifespan of the pumps. Airless bellow pumps, which can be configured to be air-driven, electrically driven, or hydraulically driven, offer flexibility in power sources to suit different application requirements. Unlike conventional piston airless pumps that can generate higher shear forces—potentially causing increased temperatures and mechanical stress on the UV paint—these low-shear systems minimize the risk of degrading sensitive components within the paint formulation. Excessive shear forces can lead to undesirable effects such as changes in viscosity, aeration or even thermal degradation of the paint constituents. These changes can adversely affect the application process and the performance of the final cured coating. In extreme cases, increased temperatures from shear can accelerate premature polymerization or curing reactions within the pump, leading to blockage or equipment damage. By employing low-shear pumping systems like airless double diaphragm pumps and bellows pumps (with electric or hydraulic conversion), the paint is handled gently, preserving its optimal rheological properties. This gentle handling ensures a smooth and even application, maintaining consistent flow rates and spray patterns. Consequently, the quality and durability of the coating are preserved, resulting in a high-performance finish that meets the required specifications. In one embodiment of a surface marking system of the invention the system comprises a flow meter connected to a software controller for allowing precise control over the actual amount of paint being applied, whereby the flow meter continuously monitors and adjusts the paint flow rate in real time. This setup allows the operator for precise control over the actual amount of paint being applied which supports maintaining a consistent layer thickness. The flow meter continuously monitors and adjusts the paint flow rate in real time, and the software controller displays the application in real time based on the speed of the mobile unit and other variables such as line width, ensuring that the correct amount of paint is consistently applied across the surface. This level of control not only ensures that the coating is applied at the correct thickness but also significantly reduces the risk of errors and variations that are common in less controlled systems, such as manual roller applications. By providing such precise control, the system delivers a professional, industry-standard application, ensuring that the final product is durable, fully cured, and meets the highest quality standards. In one embodiment the mobile units are equipped with speed control systems to enhance application consistency and curing efficiency. Implementing speed control allows these mobile units to replicate the continuous, set-speed conveyor belts commonly used in industrial UV curing environments. This replication ensures consistent application rates and uniform curing, eliminating variability caused by operator speed inconsistencies during manual operation. The invention optionally incorporates electric transaxle drives. These drives, derived from technologies used in industrial trolleys and mobility scooters, offer precise speed control in a compact and efficient package. Operators can easily manage the application speed using these electric transaxle systems, ensuring consistent coating thickness and minimize curing failures across different working environments. In one embodiment of a surface marking system of the invention the system comprises an e-drive for maintaining a constant speed and a consistent application speed. In one embodiment of a surface marking system of the invention the system comprises an electric height adjustment system for optimizing the distance between the spray nozzle and the surface and for controlling the line width. Via the feature of electric gun height adjustment the operator can maintain and configure the optimal distance between the spray nozzle and the application surface, without interrupting the application ensuring correct line width. In another embodiment of a surface marking system of the invention the system comprises a dual or triple laser line projection system providing visual cues for maintaining an accurate line width during the marking process, further enhancing the precision and reliability of the application process. Line width in spray applications is influenced by several factors, including the height of the spray gun above the surface, the type and size of the nozzle or spray tip, the viscosity of the paint, the spray pressure, and the speed of the application unit. Environmental conditions, particularly ambient temperature, can significantly affect these factors—most notably the paint's viscosity - during the application. As temperatures fluctuate throughout the day, the viscosity of the paint changes correspondingly. To maintain a consistent line width under these varying environmental conditions, it is efficient and practical to have the ability to adjust the height of the spray gun relative to the surface. By modifying the gun height, the operator can compensate for changes in paint viscosity and other environmental factors without needing to change the nozzle or adjust the spray pressure frequently. Raising the spray gun increases the distance between the nozzle and the surface, resulting in a wider spray pattern and broader line. Conversely, lowering the spray gun decreases this distance, producing a narrower spray pattern and line. The electric gun height adjustment feature optimizes the distance between the spray nozzle and the application surface. This system ensures consistent line width by maintaining the correct spray height without having to interrupt the operation, regardless of surface variations or operator handling. By automating this aspect of the process, the operator or support personnel can remain at a safe distance from the application section, reducing exposure to potentially hazardous environments while ensuring precise line application. This system is advantageous on smaller mobile road marking systems. An (electric) height adjustment system can also be applied to the LED UV light source unit for adjusting the height of the light source compared to the surface to be marked. To further facilitate precision and control of the application process, the system integrates a dual or triple laser line projection system mounted at the rear of the spray gun, providing visual cues for maintaining an accurate line width during the marking process. This laser system visually displays the intended width of the line on the surface behind the spray application. The operator can visually monitor these laser guides, ensuring that the application remains within the desired parameters, resulting in consistent and accurate line marking. This combination of automated height adjustment and visual laser guidance significantly improves the reliability and precision of the line-marking process. In one embodiment of a surface marking system of the invention and as an enhanced safety feature, the system comprises an overspray suction system configured as a spray booth surrounding the spray gun and nozzle, and equipped with suction mechanisms to capture overspray particles during paint application. The overspray suction system is designed to minimize the dispersion of paint particles during application. The system is particularly beneficial in indoor settings, where controlling overspray is critical for maintaining a clean work environment and reducing environmental contamination and health risks related to UV spray applications. Integrated into the marking system, the suction system can be activated as needed based on specific application requirements. Positioned near the spray gun / nozzle, it creates a controlled section that captures and extracts overspray particles before they can disperse into the surrounding environment. By effectively reducing the amount of airborne paint particles, the system helps prevent unintentional deposition on unintended surfaces and minimizes exposure risks to operators and bystanders. In one embodiment of a surface marking system of the invention, the power supply is a full battery system comprising one or more rechargeable power stations. The power stations comprise multiple scalable and exchangeable batteries. To meet the high energy demands of the LED UV light sources and all other features, the system comprises a full battery system. This approach ensures continuous, reliable power delivery for high-intensity UV curing, even in remote or urban settings where traditional power sources may be limited. The interchangeable power sources can function either as the primary power supply or as a supplementary power source in addition to existing engine-driven systems. This approach allows for the seamless integration of high-intensity UV curing technology into small, compact mobile units, providing all the advantages of an industrial-grade system in a highly portable format without the need of being connected to an electrical plug. Given the substantial energy requirements of UV light sources - recreating the controlled conditions of a controlled industrial conveyor belt on a mobile platform in non-controlled outdoor environments - traditional power solutions like alternators alone are often insufficient and not desireable in indoor settings. To address this, the invention incorporates high-capacity portable power stations. These portable power stations are rechargeable battery units that can be charged via solar energy or standard power outlets, delivering both AC and DC power for extended periods. One of the key advantages of some of these portable power stations is their ability to handle high peak current draws, thanks to their high-quality pure sine inverters. They can deliver high continuous current, ensuring that the LED UV light sources receive consistent power during extended marking operations. While these portable power stations are limited in capacity, their flexibility allows them to be used in conjunction with a traditional alternator connected to the engine. The alternator can recharge the portable power station while it is in use, effectively extending its operational time. Additionally, the modular design of these power stations means they can be quickly and easily exchanged for fully charged units, ensuring continuous operation without downtime. This system not only enhances the mobility and efficiency of the marking unit but also ensures that the power supply remains consistent, even in remote or urban settings where access to traditional power sources may be limited. By integrating these interchangeable power sources, the mobile unit can maintain the high energy output necessary for optimal UV curing, while also offering the flexibility to adapt to various environmental and operational conditions. This makes it a robust and versatile solution for modem road marking applications, capable of delivering industrial-quality results in a compact, portable form. In one embodiment of the invention the power supply for the high energy demands of UV is provided by one or more (portable) power stations. (Portable) power stations are a line of rechargeable portable batteries that charge via solar energy or power outlets and produce AC and DC power which lasts for several hours. An advantage of some battery power stations is that they typically have a high peak current draw due to high-quality pure sine inverters, some even even able to reach 18000W / 80 A peak. Another advantage is that it can deliver similar amounts of continuous current to a standard electric plug, 3600W / 16 A. These battery power stations can be used alone or in combination with a traditional alternator of an engine for recharging the portable power station. The portable power stations are equipped with high-quality pure sine inverters capable of handling high peak current draws. The stations can be recharged via solar energy or standard outlets, providing flexibility and sustainability. The stations can handle high peak current draws and provide both AC and DC power. Modularity of power stations is a major advantage whereby power stations are designed to be easily exchanged for fully charged units, ensuring continuous operation without downtime. Alternatively, to keep production going, low battery power stations can be exchanged for fully charged ones, while being recharged in the meantime. Battery power stations can optionally be recharged via alternators. This allows the use high-intensity UV light sources of any size: small focus lights, bigger flood lights or combinations thereof. The materials used in the construction of the system are chosen for their resistance to corrosion, UV radiation, and other environmental factors, ensuring long-term durability and reliability. The system's components are made of high-quality materials, such as corrosion-resistant metals and UV-resistant polymers, ensuring long-term durability and reliability and ensuring to withstand harsh conditions. The system is capable of operating effectively in extreme temperatures and varying humidity levels, making it suitable for use in diverse environments. In a specific embodiment of the invention the system is a fully electric battery-driven mobile unit comprising a frame for housing one or more system components comprising a paint applicator and a closed loop heated hose system, an LED UV light source comprising a UV protective shroud surrounding the LED UV light source, and at least an exchangeable and / or reloadable battery power station. The mobile unit is operated by a human operator or remotely controlled. The system components are modular and scalable depending on the size of the mobile unit. The mobile unit is operated by a human operator or remotely controlled. Some examples of mobile units are illustrated next. In a first example an electric walk behind UV mobile unit comprises the following components: a screw compressor, KTC compact 2, delivery 3101 / min at 6 bar, energy draw: 2,7 KW; an airless double diaphragm pump, processable materials: water-borne, solvent-borne, abrasive, shear sensitive, sensitive to moisture, maximum material pressure: 250 bar (at 6 bar air inlet), volumetric flow per double stroke: 10 cm3 (2L / min flow per minute), transmission ratio: 40 :1, material temperature: 10-80 °C; a high-intensity LED UV curing light, 250mm long, 150mm wide, 405nM wavelength (150mm) and 365nM (100mm), 405nM LED diodes with 60 degrees glass lenses, 365nM LED diodes with 30 degrees glass lenses, intensity 3000mW (405nm), 2000mW (365nM) at 30mm, air cooled, energy needed: 3000W at 100% power; a heated hose / gun, 1 x 5m 1 / 4” airless hose with 300 Watt heating power per hose (230 V - 50 Hz), max. working pressure: 250 bar, temperature control: 20 - 100 ° C (stepless), manual airless guns with recirculation (+ recirculation valve); an electric height adjustment, manually operated electric linear module with DC motor; engine: electric capacity: 2,1 Kwh per battery each, rated power: 3600 W, peak power: 18000W; two IG1 batteries in frame, one for compressor, one for UV light source, heating and height system. In a second example an engine driven walk behind UV mobile unit comprises the following components: a converted electric bellow pump airless; processable materials: water-borne, solvent-borne, abrasive, shear sensitive, sensitive to moisture; electric drive: Graco Mark VII pump engine with customized adaptor fur pump section; pump section: Graco 35:1 Bellow pump with UV packings into protective shroud; max. material pressure: 220 bar; volumetric flow per double stroke: approx.. 110 cm3 (approx. 6 l / min); UV light source: higher-intensity LED UV curing light, 250mm long, 150mm wide, 405nM wavelength (150mm) and 365nM (100mm), 405nM LED diodes with 60 degrees glass lenses, 365nM LED diodes with 30 degrees glass lenses, intensity 3000mW (405nm), 2000mW (365nM) at 30mm, air cooled, energy needed: 3000W at 100% power, heated hose / gun, 1 x 7,5m 3 / 8” airless hose Heated hose with 450 Watt heating power per hose (230 V - 50 Hz), max. working pressure: 250 bar, temperature control: 20 - 100 ° C (stepless), manual airless guns with recirculation (+ recirculation valve); electric height adjustment: manual operated electric linear module (hard-anodized, ball bearings carriage length 150 mm) with DC motor; engine: electric (battery), 2 x Instagrid IG1, 1 for compressor 1 for UV light source, heating and height system, capacity: 2,1 Kwh per battery each, rated power: 3600 W, peak power: 18000W, battery in frame: 2 IG1 batteries in frame. In a second aspect the invention relates to a method of marking a surface, such as a ground surface or any other surface. The present invention discloses a method of marking a surface comprising the steps of: a) moving a surface marker along the surface, the surface marker comprising a paint applicator for applying a coating layer of UV paint, an optional dispenser for dispensing optically transmissive components; and an LED UV light source configured to emit UV light with a wavelength of 365 nM -495 nm and an irradiance of at least 1900 mW / cm2, the LED UV light source further configured to deliver an energy dose of at least 2500 mJ / cm2; b) applying a primer comprising 0% by weight pigment, optionally 2-4% by weight; c) applying UV light to the primer and curing the primer, wherein the primer is not fully cured but gelled; d) optionally repeating steps b and c several times for applying multiple layers of primer; e) applying a base coat comprising 3-8% by weight pigment; f) applying UV light to the base coat and curing the base coat, wherein the base coat as top coat is fully cured, or wherein the base coat is not fully cured but gelled if a further top coat is applied onto the base coat; g) applying an optional top coat, wherein the top coat is a clear coat or comprising 3-8% by weight pigment; and h) applying UV light to the optional top coat and curing the top coat fully. In one embodiment the top coat is cured using an LED UV light source with a dual wavelength of 405nM (front zone deep cure) and 365nm (back zone top cure). An example of a method for applying an indoor UV linemarking material in multiple layers comprising a UV primer, a base coat and an optional top coat is set out as follows. Applying the UV linemarking primer (clear primer with 0% by weight pigment or optionally containing 2-4% by weight pigments such as TiO2). The primer can be applied by roll but preferably by airless spraying (airless double diaphragm pump pressure at 80-140 bar) a layer onto the surface with a thickness from 50-100 micron. The primer is applied on concrete or difficult surfaces to ensure a good adhesion for the paint. A closed loop system with heated hose ensures a temperature of 25-40 degrees, maintaining a stable viscosity for the UV paint. The primer is not fully cured but lightly gelled to ensure optimal intercoat adhesion for the next layer the linemarking Primer using a separate LED UV light source mobile unit (wavelength, 405nM only for deep curing) that passes over the applied material at a distance of 30mm. The gelation process is initiated as soon as possible after the application of the UV primer. The base coat is applied on a gelled (sticky) primer. This is the higher pigmented layer (containing 4-8% by weight pigments such as TiO2) for good opacity. The base coat can be applied by roll but preferably by airless spraying (airless double diaphragm pump pressure at 80-140 bar) a layer onto the surface with a thickness from 80-200 micron. A closed loop system with heated hose ensures a temperature of 25-40 degrees, maintaining a stable viscosity for the UV paint. The UV linemarking base coat is now fully cured (if this is the last layer, or gelled to ensure optimal intercoat adhesion for the UV top coat layer clear or pigmented) by using a separate LED UV light source mobile unit (wavelength, only 405nM if aiming for gelation or 405nM and 365nm aiming for full cure) that passes over the applied material at a distance of 30mm. The gelation or curing process is initiated as soon as possible after the application of the UV primer. Optionally, when the basecoat is gelled and not fully cured, a UV top coat is applied over base coat. This is an extra layer that makes the system stronger and more durable. The UV top coat is applied on a gelled (sticky) base coat. This is a clear coat (optionally containing 3-8% by weight pigments such as TiO2). The top coat contains waxes to make the line more durable and avoid dirt pick up. Standard they are without pigments, but optionally can contain pigments for good opacity. The UV top coat can be applied by roll but preferably by airless spraying (airless double diaphragm pump pressure at 80-140 bar) a layer onto the surface with a thickness from 80-150 micron. A closed loop system with heated hose ensures a temperature of 25-40 degrees, maintaining a stable viscosity for the UV paint. The UV linemarking top coat is fully cured by using a separate LED UV light source mobile unit (wavelength, 405nM and 365nm for deep and top cure) that passes over the applied material at a distance of 30mm. The curing process is initiated as soon as possible after the application of the UV primer. In an example the mobile curing unit comprises an LED UV flood light source whereby the strength and curing speed are optimized based on the thickness of the UV linemarking material. The LED UV light source has a uniform strength of approx. 3000 mW / cm2 at approx.40mm (at approx..80% of power) providing a dose of 2500-3000 mJ / cm2, allowing curing speeds up to approx. 0,5-1,5km / h. The LED UV light source uses 3000W (at. Approx. 80% of power). The mobile curing unit has an optional electric transaxle drive (gear Ratio: 33.7:1, Motor: 600W-DC 24V-2600 RPM), to ensure that the operator maintains a continuous speed during the curing process, to ensure a consistent curing speed. This creates a continuous process similar to UV curing applications in controlled industrial UV applications. The optional electric transaxle drive comes with a controller on the steering bar, so the operator can control everything during the application. The unit comes with two pre-set speed (for gelling and full curing speeds), a free speed functions (operator via a thumb throttle), reverse / front function, a horn, an emergency stop, battery indicator and the possibity to disconnect should the battery be empty to be able to still move the unit. The LED UV light source unit is 25cm (front to back) long and 15cm wide, and has two sections with different wavelengths. The LED UV light source comprises an aluminium housing with a 3 mm quartz glass protective panel, IP67 metal connection panel with LED 405nm (front) mixed with 365 nm (back) with narrow beam glass dome LEDs divided into sections every 5 cm each with 95 LEDs per section, sections can be controlled individually or together via controller, 12 VDC 60 mm x 60 mm cooling fan. The front section of the LED UV light source emits a wavelength of 405nM for deep curing, length 15cm, (optionally 20cm), strength approx. 3000 mW / cm2 at 40mm distance (LEDS with narrow beam lenses), LEDs divided into 5 subsections, 5 cm each with 95 LEDs per subsection, subsections can be controlled individually or together. Used to deep cure the UV material applied on the substrate The back section emits a wavelength of 365nM for top curing, length 10cm, (optionally 5, strength approx. 2400 mW / cm2 at 40mm distance (LEDS with narrow beam lenses), LEDs divided into 5 subsections, 5 cm each with 95 LEDs per subsection, subsections can be controlled individually or together. Used to deep cure the UV material applied on the substrate. The LED UV light source unit has a protective hood with brushes and UV filtering PET-G body to filter and block the UV light as much as possible for the safety of operators and bystanders of the application. Both the LED UV curing light source and the paint gun are adjustable in height via an electric linear glider height system. The height can be changed by the operator without having to interrupt the operation and without the help of any other operator. The power of the mobile unit is 100% supplied via two expandable power stations reworked in the frame. Each power station has an output voltage of 230 V (AC) / 50 Hz, a rated capacity of 2.1 kWh, a power output of 3.6 kW (16 A) and a peak power output of 18.0 kW (80 A). The power supply is configured as follows: on the UV paint application unit: one power station is used to supply the compressor of electric power in order to feed the air motor of the double diaphragm pimp, and one power station is used to supply tank / hose heating, electric height set up of necessary power. On the UV curing unit: one power station is used to supply the LED UV light source of the necessary power, and one power station is used to supply the optional electric transaxle drive. The power stations can optionally be exchanged by a sliding mechanism to avoid downtime during charging In another embodiment of a method of marking an indoor surface steps b and c are repeated several times to apply and gel-cure one to three layers of primer. The base coat is top coat and is cured using an LED UV light source (4) with a dual wavelength of 405nM (front zone deep cure) and 365nm (back zone top cure). As such, the present invention discloses an alternative method of marking an indoor surface, comprising 1 to 3 layers of primer sealed with a top coat, the method comprising the steps of: a) applying a primer with a clear primer comprising 0% by weight pigment, optionally 2-4% by weight; b) curing the primer using an LED UV light source, wherein the primer is not fully cured but gelled; c) repeating steps a and b several times for applying multiple layers of primer; d) further applying a top coat, wherein the top coat is a clear coat comprising 3-8% by weight pigment, and the top coat comprises waxes; and e) curing the top coat fully using an LED UV light source with a dual wavelength of 405nM (front zone deep cure) and 365nm (back zone top cure). An example of a method for applying an indoor UV linemarking material comprising multiple layers of pigmented primer and a top coat is set out as follows. Applying a first coat of UV linemarking primer (containing 2-4% by weight pigments such as TiO2). The primer can be applied by roll but preferably by airless spraying (airless bellow pump with UV resistant packings, pressure at 80-140 bar) 1 layer onto the surface with a thickness from 50-100 micron (first layer preferably as thin as possible for optimal adhesion). The primer is applied ensure a good adhesion and is pigmented to provide more opacity for pigmented UV systems. The closed loop system with heated hose ensures a temperature of 25-40 degrees, maintaining a stable viscosity for the UV paint. The UV linemarking primer is lightly gelled to ensure optimal intercoat adhesion for the next layer using an on board LED UV light source on the airless application unit (wavelength, 405nM ) that passes over the applied material at a distance of 30mm. The gelation process is initiated as soon as possible after the application of the UV primer. The previous steps are repeated at least one more time until the required opacity has been reached. The UV top coat (Clear or pigmented containing 3-8% by weight pigments such as TiO2) can be applied by roll but preferably by airless spraying (airless bellow pump pressure at 80-140 bar) a layer onto the surface with a thickness from 80-150 micron. A closed loop system with heated hose ensures a temperature of 25-40 degrees, maintaining a stable viscosity for the UV paint. The UV top coat is fully cured using an on board LED UV light source on the airless application unit (wavelength, 405nM and 365nm) that passes over the applied material at a distance of 30mm. The gelation process is initiated as soon as possible after the application of the UV primer. The LED UV light source is 25cm (front to back) long and 15cm wide, and uses two wavelengths. LED UV unit consist of an Aluminium housing with a 3 mm quartz glass protective panel, IP67 metal connection panel with LED 405nm (Front) mixed with 365 nm (back) with narrow beam glass dome LEDs divided into zones every 5 cm each with 95 LEDs per zone, zones can be controlled individually or together via controller, 12 VDC 60 mm x 60 mm cooling fan PCB specifications Aluminium PCB, 70 pm copper, white solder resist, black. The front zone of the LED UV light source emits a wavelength of 405nM, length 15cm, (optionally 20cm), strength approx. 3000 mW / cm2 at 40mm distance (LEDS with narrow beam lenses), LEDs divided into 5 subzones, 5 cm each with 95 LEDs per subzone, subzones can be controlled individually or together. Used to deep cure the UV material applied on the substrate. The back zone of the LED UV light source emits a wavelength of 365nM, length 10cm, (optionally 5, strength approx. 2400 mW / cm2 at 40mm distance (LEDS with narrow beam lenses), LEDs divided into 5 subzones, 5 cm each with 95 LEDs per subzone, subzones can be controlled individually or together. Used to deep cure the UV material applied on the substrate In an example the mobile UV application unit has the following specs: • Airless manual paint gun with recirculation valve • Laser indication for line width of the linear height adjustment system for the paint gun to allow the operator to see and adjust the height of the gun on while doing the operation • integrated UV light source on mobile unit with linear height adjustment system UV airless bellow pump on Mobile UV unit: • Standard airmotor for bellow pump, (in this case standard Graco bellow pump 35:1, with liquid section of 110cc per stroke) • Optionally the standard air motor is replaced by an electronic motor (or alternatively a hydraulic motor) that provides a similar pump stroke for the bellow underpump (for example graco Mark VII). The electric motor (or alternative such as hydraulic engine) is connected via a customised connection and protective hood. This eliminates the need of a compressor to feed an air motor and work more energy efficient (resulting in less downtime recharging or replacing batteries on the mobile unit) AND having less components on the unit) • The unit has a suction hose that can go directly into a closed container or hopper. Optionally the hopper can be heated • On board piston compressor (only needed with air motor option) • The power is 100% supplied via 2 expandable power stations reworked in the frame. Each power station has an output voltage of 230 V (AC) I 50 Hz, a rated capacity of 2.1 kWh, a power output of 3.6 kW (16 A) and a peak power output of 18.0 kW (80 A). Power stations can be replaced by a sliding system worked into the frame Mobile spray application drive for controlled speed: • The mobile curing unit has an optional electric transaxle drive (gear Ratio: 33.7:1, Motor: 600W-DC 24V-2600 RPM), to make sure the operator maintains a continuous speed during the combined application and curing process, to ensure a consistent speed. This creates a more controlled process similar to UV applications in controlled industrial UV settings • The optional electric transaxle drive comes with a controller on the steering bar, so the operator can control everything during the application. The unit comes with 2 pre-set speed (for gelling and full curing speeds), a free speed functions (operator via a thumb throttle), reverse / front function, a horn, an emergency stop, battery indicator and the possibility to disconnect should the battery be empty to be able to still move the unit • The UV application unit with UV light sources comes with an optional software via a Canbus system that • In a standard version: displays UV material pressure, speed indication, meters travelled and sprayed. The encoder is connected to a precision measuring wheel that measures approx. 8 points per millimeter to guarantee a precise display of the speed travelled. The unit can be calibrated by the user to make sure the displayed speed and distances are correct • In an advance version: displays UV material pressure, speed indication, meters travelled and sprayed, floor temperature, air temperature and humidity and with the optional flow meter displays the exact thickness of the applied line. This all connected via an GPS system with localization and an online system to download the information from the application unit. The encoder is connected to a precision measuring wheel that measures approx. 8 points per millimeter to guarantee a precise display of the speed travelled. The unit can be calibrated by the user to make sure the displayed speed and distances are correct In yet another embodiment of a method for marking a surface, only a UV top coat is applied and cured as a protective UV coat over an existing base coat. As such, the present invention further discloses a hybrid method of indoor line marking, whereby an UV top coat (clear top coat or with 3%-8% by weight pigments such as TiO2) is applied as a protective UV coat over other linemarking products. This system is developed to allow more cost effective base coat applications with the benefits of an UV top coating. An example of a hybrid method is set out as follows. Applying a base coat of standard material for indoor usage, where the compatibility (for adhesion) is certified and tested by the manufacturer of the UV coating. This can be water based, solvent based, 2-component PU, MMA or epoxy systems applied. This can be applied in any thickness, color according to the manufactures guideline. Alternatively this can be an odourless 2-component UV based material cured by a peroxide initiator. Wait until is cured (mainly important that all VOCs are out of the system). The UV top coat (clear or pigmented containing 3-8% by weight pigments such as TiO2) can be applied by roll, but preferably by airless spraying (airless bellow pump pressure at 80-140 bar) a layer onto the surface with a thickness from 80-150 micron. A closed loop system with heated hose ensures a temperature of 25-40 degrees, maintaining a stable viscosity for the UV paint. The UV linemarking top coat (clear or pigmented containing 3-8% by weight pigments such as TiO2) is fully cured using an on board LED UV light source on the airless application unit (wavelength, 405nM and 365nm) or via a separate UV curing unit that passes over the applied material at a distance of 30mm. The gelation process is initiated as soon as possible after the application of the UV primer. The LED UV light source is 25cm (front to back) long and 15cm wide, and uses two wavelengths. LED UV unit consist of an aluminium housing with a 3 mm quartz glass protective panel, IP67 metal connection panel with LED 405nm (Front) mixed with 365 nm (back) with narrow beam glass dome LEDs divided into zones every 5 cm each with 95 LEDs per zone, zones can be controlled individually or together via controller, 12 VDC 60 mm x 60 mm cooling fan PCB specifications Aluminium PCB, 70 pm copper, white solder resist, black. The front zone of the LED UV light source emits a wavelength of 405nM, length 15cm, (optionally 20cm), strength approx. 3000 mW / cm2 at 40mm distance (LEDS with narrow beam lenses), LEDs divided into 5 subzones, 5 cm each with 95 LEDs per subzone, subzones can be controlled individually or together. Used to deep cure the UV material applied on the substrate. The back zone of the LED UV light source emits a wavelength of 365nM, length 10cm, (optionally 5, strength approx. 2400 mW / cm2 at 40mm distance (LEDS with narrow beam lenses), LEDs divided into 5 subzones, 5 cm each with 95 LEDs per subzone, subzones can be controlled individually or together. Used to deep cure the UV material applied on the substrate In a third aspect the invention relates to a surface marking for indoor or off-highway surfaces applied by a surface marking system or by a method as disclosed above, characterised in that the marking comprises a UV curable coating layer comprising a paint composition adapted for curing by exposure to UV light, the paint composition comprising: a) one or more multifunctional acrylate oligomers in a concentration of 25 to 45% by weight; b) one or more high molecular acrylic binders for enhanced adhesion and flexibility with a molecular weight Mn 10.000-20.000 Daltons: 1 to 5% by weight; c) one or more multi and / or mono-functional monomers in a concentration of 20 to 45% by weight; d) a main photo initiator in a concentration of 1 to 5% by weight; and e) one or more alternative or supplementary photo initiators for different UV light ranges in a concentration of 1 to 5% by weight. The paint composition further comprises: a) a polymerization inhibitor or stabilizer for radically curable resins in a concentration of 0,1 to 0,5% by weight; b) one or more polymeric, silicone-free and silicone containing flow and levelling agents for better substrate wetting in a concentration of 0,1 to 1,0% by weight; c) one or more defoamers based on organic polymers, silicone free and silicone based to prevent air entrapment in a concentration of 0,1 to 3,0% by weight; d) a hindered amine light stabilizer (HALS) to reduce degradation by sunlight in a concentration of 0,1 to 1,5% by weight; e) one or more pigments for color and opacity in a concentration of 0,5 to 5% by weight; f) one or more fillers / extenders for opacity and mechanical properties in a concentration of 15 to 25% by weight; g) one or more adhesion promoters for better adherence to substrates in a concentration of 0,5 to 1,5% by weight; and h) one or more rheology modifiers based on hydrophobic pyrogenic silica for optimal flow, leveling and sedimentation in a concentration of 0,1 to 1,5% by weight. Optionally the pigment of a coating layer is white and is titanium dioxide. In one embodiment the surface marking comprises a primer, a base coat and an optional top coat. The primer has a thickness of 0-200 pm and a concentration of pigment of 0-10% by weight, preferably 0-4% by weight. The base coat has a thickness of 0-400 pm and a concentration of pigment of 0-10% by weight, preferably 5-8% by weight. The top coat has a thickness of 50-250 pm and a concentration of pigment of 0-10% by weight, preferably 0-5% by weight. In a specific embodiment the surface marking is a UV cured coating layer comprising one or more layers of primer, a base coat comprising 4-8% by weight pigment and an optional top coat comprising 3-8% by weight pigment. In one embodiment the primer is a clear primer comprising 0% by weight pigment or comprising 2-4% by weight pigment. In a specific embodiment the surface marking for off-highway or indoor surfaces comprises an existing base coat and a top coat applied on said existing base coat, the base coat comprising any material (dried or cured in any manner), wherein the top coat is UV cured and has a thickness of 80-150 micron, wherein the top coat is a clear coating or a pigmented coating comprising 3-8% by weight pigment. With the intention of better showing the characteristics of the invention, some embodiments according to the invention are described, by way of an example without any limiting nature, with reference to the accompanying drawings, wherein: figure 1 represents an embodiment of a frame for an electric driven mobile unit according to the invention; figure 2 represents an embodiment of a frame of a mobile unit according to the invention comprising a frame integrated power pack and an LED UV light source with height adjustment; figure 3 represents an embodiment of a mobile unit according to the invention further comprising a unit having an electric bellow pump, a heated tank and a flow meter, and a laser indicator; figure 4 represents an embodiment of a mobile unit according to the invention comprising a unit having an air-powered pump, a heated tank and a flow meter; figure 5 represents an embodiment of a mobile unit according to the invention comprising a unit having a compressor (more than 2001 / m); figure 6 represents an embodiment of a UV blocking shroud according to the invention; figure 7 represents an embodiment of an overspray suction system according to the invention; figure 8 represents an embodiment of a height adjustment system according to the invention; figure 9 represents an embodiment of a heated tank for storing UV paint according to the invention; figure 10 represents a first embodiment of an LED UV light source according to the invention; figure 11 represents a second embodiment of an LED UV light source according to the invention; figure 12 represents a third embodiment of an LED UV light source according to the invention; and figure 13 represents an embodiment of the UV curing process. Figure 1 represents an embodiment of a frame 5 for an electric driven 2 mobile unit 1 according to the invention. The frame has two wheels powered by the power supply 3 (not shown) of the marking system. The frame has a handle bar for guidance by an operator. The frame could also have remote controlled guidance and steering. The adjustment system for height, line width, flow meter, etc. could also be controlled remotely and automatically. In this way the mobile unit operator does not need to be close to the mobile unit and high-intensity UV light sources. Figure 2 further represents the mobile unit of figure 1 with a power pack 3 integrated in / on the bottom of the frame and an LED UV light source 4 held at the side of the frame mounted by holding means 16. The frame also houses an electric height adjustment system 14 for adjusting the height of the LED UV light source 4. The LED UV light source 4 has a front working section 4A and a back working section 4B. The front / back working sections are related to the driving direction of the mobile unit indicated by the arrow. Figure 3 further represents the mobile unit of figures 1 and 2 wherein the frame further houses an electric bellow pump 11, a heated tank 7, a manual (airless) pistol spray gun 6 with a heated hose, a flow meter 12 and a laser indicator 15. The frame further houses a second electric height adjustment system 14 for adjusting the height of the spray gun 6 and the laser indicator 15. Placement of the components on the frame can differ in alternative mobile units depending on the specific use, power and size of the unit. Figure 4 further represents the mobile unit of figure 3 with a compressor 10. The LED UV light source 4 and a height adjustment system is not shown in figure 4. Figure 5 represents another embodiment of a mobile unit 1 according to the invention further comprising a bead dispenser (pistol) 9 for applying optional glass beads based on gravity or by pressure. The compressor 10 has a rate of more than 200 l / min. The pump 11 is an airless double membrane or bellow pump powered by an air engine. The LED UV light source 4 is not shown in figure 5. This type of mobile unit is a larger unit and typically applies to outdoor applications. Figure 6 represents a preferred embodiment of a UV protective shroud 19. The shroud has a top panel 20 in transparent UV filtering / blocking material, two side panels 21 and a front and back panel 22. The panels surround the LED UV light source 4. Other similar configurations for a UV protective shroud surrounding the LED UV light source are possible, as long as the UV light spread out in any direction of the LED UV light source is optimally blocked or filtered from an operator or bystander. Figure 7 represents a mobile unit 1 further comprising an overspray suction system 24 mounted as a hood over the spray gun and spray nozzle 6 (not shown). The overspray suction system 24 is fixed to the frame. The suction system comprises an exhaust and a replaceable filter system to capture the overspray particles. Figure 8 represents a detail of an adjustable height adjustment system 14. The main guiding arm 17 / 18 towards the laser indicator 15 and the spray gun 6 (not shown) is adjustable in height. Figure 9 represents an embodiment of a heated tank 7 for storing UV paint according to the invention. The tank 7 mainly has the shape of a round reservoir 7a with a hopper shape 7b at the bottom, where the tank connects to a pump via outlet 7c. The connection may comprise an optional valve to open or close the tank for allowing the hopper to be dismounted easily. The tank 7a / 7b is double-sided. Figures 10 and 11 represent an LED UV light source comprising multiple sections. The sections are comprised in one light source housing 4 and are divided either according to the front / back (fig 10) or the left / right (fig 11) sections of the light source. Figure 10 represents a first embodiment of an LED UV light source according to the invention. The LED UV light source (housing) is a uniform flood light, and is divided into two different irradiance sections. Alternatively the LED UV light source (housing) can be divided in more than two irradiance sections. This setup avoids separate housings, but mainly it avoids potential gaps in between the flood light and the focus light. This set up further allows bigger light sources, providing a longer dwell time, at higher speeds, but allows energy savings on mobile units that have limited energy supply. The first irradiance section 23a is a flood LED UV light source with a uniform intensity typically between 2000 mW / cm2 up to 5000 mW / cm2 The strength is up to 9000mW for a water-cooled UV light source. This irradiance section 23a is typically configured at the back of the light source 1. The second irradiance section 23b at the front of the light source 1 is a higher-intensity LED UV light source with an intensity typically between 4000 mW / cm2 up to 16000 mW / cm2. The strength is up to 16000mW for a water-cooled UV light source in bigger units creating extra punch in peak irradiance. The sections can be organized by different PLC’s, switches, energy supply, etc. Alternatively, the stronger irradiance section can also be in front of the LED UV light source housing. Figure 11 represents a second embodiment of an LED UV light source according to the invention. Figure 11 represents a flood LED UV light with three uniform LED UV sections. The two energy saving sections 23a at the lengthwise side parts of the LED UV light source can be separately switched on or off to save energy. The three sections have an identical irradiance and wavelength in this example. As an example the total width of the LED UV light source is 30cm. Section 23b has a width of 20 cm, section 23a is 5 cm wide per section. Via the controller section 23a can be switched off (individually or both) to save energy. If both sections 23a are switched off, the width of the light source that is working is now 20cm (section 23b). This allows the operator to easily cure 15cm lines, while doing significant energy savings. Should the operator encounter a 20cm line, he can switch on one or both sections 23a and cure the line. Figure 12 represents a third embodiment of an LED UV light source according to the invention. Figure 12 represents an LED UV light source comprising different irradiance and wavelength sections. The light source (housing) 1 comprises an LED UV flood light with different sections. As per example the total length of the light source is 500mm long and 300 mm wide. The first irradiance section 23a near the front of the light source is an LED UV light source 405nM wavelength with a higher intensity typically between 4000 mW / cm2 and up to 16000 mW / cm2 for a water-cooled UV light source in bigger units creating extra punch in peak irradiance. The second irradiance section 23b is an LED UV light source 405nm wavelength with a lower intensity typically between 2000 mW / cm2 up to 5000 mW / cm2. The strength could go up to 9000mW for a water-cooled UV light source. The third irradiance section 23c near the back of the LED UV light source is an LED UV light source 365nm wavelength with an intensity typically between 2000 mW / cm2 up to 3000 mW / cm2 The strength could go up to 6000mW for a water-cooled UV light source. Figure 13 represents an embodiment of a UV application and curing process of 5 spraying a layer of UV paint with a spray gun 6, using a laser-guided line width indicator 15 for enhancing the precision and reliability of the application process, optionally dispensing glass beads with a bead dispenser 9 on the freshly applied wet UV paint and curing the coating layer with the drop-on beads with an LED UV light source 4. 10

Claims

1. A surface marking system (1) for the application and UV curing of a coating layer on a road or surface, the system comprising a paint applicator (6), an LED UV light source (4) and a power supply (3), whereby the system is movable over a road or surface, and the system is configured such that as it moves, the paint applicator (6) applies a coating layer of UV paint on the road or surface, and the LED UV light source (4) cures the coating layer, whereby the LED UV light source (4) is configured to emit UV light with a wavelength in the range of 365 nM -495 nm, preferably in the range of 365 nM - 405 nM, characterised in that the LED UV light source (4) has an irradiance of at least 1900 mW / cm2, and is configured to deliver an energy dose of at least 2500 mJ / cm2, wherein the power supply (3) provides a power of at least 2000 W, whereby the LED UV light source (4) is configured to cure a coating layer having a thickness of up to 400 pm in a single pass.

2. The surface marking system according to claim 1, characterised in that the LED UV light source (4) has an irradiance of at least 2000 mW / cm2 and up to 16000 mW / cm23. The surface marking system according to claim 1 or 2, characterised in that the LED UV light source (4) comprises multiple UV sections (23a,23b,23c) having a different irradiance and / or wavelength.

4. The surface marking system according to claim 3, characterised in that the UV sections have a higher irradiance between 4000 mW / cm2 and up to 16000 mW / cm2 and / or a lower irradiance between 2000 mW / cm2 up to 3000 mW / cm2.

5. The surface marking system according to claim 3, characterised in that the UV sections have a higher wavelength in the range of 405 nm and / or a lower wavelength in the range of 365 nm.

6. The surface marking system according to any of claims 3 to 5, characterised in that a higher intensity or wavelength section is configured near the front of the light source, and a lower intensity or wavelength section is configured near the back of the light source.

7. The surface marking system according to any of the previous claims, characterised in that the LED UV light source (4) comprises a UV floodlight with an intensity of 2000-6000mW / cm2, preferably 2500-4000mW / cm2, and a more focused UV light source with a high-intensity of 5000-16000mW / cm2, preferably 5000-8000mW / cm2.

8. The surface marking system according to any of the previous claims, characterised in that the LED UV light source (4) comprises multiple energy saving sections (23a,23b,23c) of different width and / or different length, whereby each section can be switched on or off.

9. The surface marking system according to claim 8, characterised in that the LED UV light source (4) comprises multiple energy saving sections (23a,23b,23c) of different width over the full length, whereby each section has a uniform irradiance and wavelength.

10. The surface marking system according to claim 8, characterised in that the LED UV light source (4) comprises multiple energy saving sections (23a,23b,23c) of different length over the full width, whereby the sections have a different intensity and / or wavelength.

11. The surface marking system according to any of claims 8 to 10, characterised in that the multiple sections (23a, 23b, 23c) are independently configurable with an adjustable intensity settings ranging from 0 to 100%.

12. The surface marking system according to any of the previous claims, characterised in that the LED UV light source comprises one or more LED components.

13. The surface marking system according to any of claims 1 to 12,characterised in that the LED UV light source (4) is configured to cure acoating layer having a thickness of up to 400 pm in a single pass.

14. The surface marking system according to any of claims 1 to 13,characterised in that the LED UV light source (4) is configured to cure orgel a UV adhesion primer having a thickness of 0-200 pm in a single pass, the coating layer comprising a concentration of pigment of 0-10% by weight, preferably 0-4% by weight.

15. The surface marking system according to any of claims 1 to 14, characterised in that the LED UV light source (4) is configured to cure or gel a UV base coat having a thickness of 0-400 pm in a single pass, the coating layer comprising a concentration of pigment of 0-10% by weight, preferably 5-8% by weight.

16. The surface marking system according to any of claims 1 to 15, characterised in that the LED UV light source (4) is configured to cure or gel a UV top coat having a thickness of 50-250 pm in a single pass, the coating layer comprising a concentration of pigment of 0-10% by weight, preferably 0-5% by weight.

17. The surface marking system according to any of the previous claims, characterised in that the coating layer comprises a clear coat which is clear of pigment (0%).

18. The surface marking system according to any of the previous claims, characterised in that the surface is an off-highway road such as a private parking or an airport, or an indoor surface such as a warehouse floor, a logistic center.

19. The surface marking system according to any of the previous claims, characterised in that the power supply (3) is a full battery system comprising one or more rechargeable power stations.

20. The surface marking system according to any of the previous claims, characterised in that the power supply (3) provides up to 10000 W.

21. The surface marking system according to claim 19 or 20, characterised in that the power stations (3) comprise multiple scalable and exchangeable batteries.

22. The surface marking system according to any of the previous claims, characterised in that the system further comprises a UV protective shroud (19) mounted on or surrounding the LED UV light source (4) for blocking and / or filtering UV radiation.

23. The surface marking system according to claim 22, characterised in that the UV protective shroud (19) comprises a top panel covering the LED UV light source (4), extending into front, back and side panels surrounding the light source and floating above the surface at 2-100 mm, preferably 5-40mm.

24. The surface marking system according to claim 22 or 23, characterised in that the UV protective shroud (19) is made of UV-filtering materials, such as polycarbonate, PET-G, or plexiglass, with polycarbonate being the preferred material.

25. The surface marking system according to any of to previous claims, characterised in that the system further comprises a closed loop heated hose system and optionally a heated paint tank (7) for maintaining the paint at a constant paint temperature of 20-50 °C, typically 30-40 °C, and a consistent viscosity.

26. The surface marking system according to claim 25, characterised in that the a closed loop heated hose system comprises a heated paint hose running from the paint tank (7) to the nozzle of the applicator (6), and optionally a heated return hose from the nozzle back to the tank (7).

27. The surface marking system according to claim 25 or 26, characterised in that the heated paint tank (7) is double-sided, optionally insulated, and comprises internal heating pads.

28. The surface marking system according to any of the previous claims, characterised in that the system comprises an e-drive for maintaining a constant speed and a consistent application speed.

29. The surface marking system according to any of the previous claims, characterised in that the system comprises a flow meter (12) connected to a software controller for allowing precise control over the actual amount of paint being applied, whereby the flow meter (12) continuously monitors and adjusts the paint flow rate in real time.

30. The surface marking system according to any of the previous claims, characterised in that the system comprises an electric height adjustment system (14) for optimizing the distance between the spray nozzle and the surface and for controlling the line width.

31. The surface marking system according to any of the previous claims, characterised in that the system comprises a dual or triple laser line projection system (15) providing visual cues for maintaining an accurate line width during the marking process.

32. The surface marking system according to any of the previous claims, whereby the system comprises an overspray suction system (24) configured as a spray booth surrounding the spray gun and nozzle, and equipped with suction (24) mechanisms to capture overspray particles during paint application.

33. The surface marking system according to any of the previous claims, characterised in that the system is a fully electric battery-driven mobile unit comprising a frame (5) for housing one or more system components comprising a paint applicator (6) and a closed loop heated hose system, an LED UV light source (4) comprising a UV protective shroud (19) surrounding the LED UV light source, and at least an exchangeable and / or reloadable battery power station (3).

34. The surface marking system according to claim 33, characterised in that the mobile unit is operated by a human operator or remotely controlled.

35. The surface marking system according to claim 33 or 34, characterised in that the system components are modular and scalable depending on the size of the mobile unit.

36. A method of marking a surface comprising the steps of:a. moving a surface marker along the surface, the surface marker comprising a paint applicator for applying a coating layer of UV paint, an optional dispenser for dispensing optically transmissive components; and an LED UV light source configured to emit UV light with a wavelength of 365 nM - 495 nm and an irradiance of at least 1900 mW / cm2, the LED UV light source further configured to deliver an energy dose of at least 2500 m J / cm2;b. applying a primer comprising 0% by weight pigment, optionally 2-4% by weight;c. applying UV light to the primer and curing the primer, wherein the primer is not fully cured but gelled;d. optionally repeating steps b and c several times for applying multiple layers of primer;e. applying a base coat comprising 3-8% by weight pigment;f. applying UV light to the base coat and curing the base coat, wherein the base coat as top coat is fully cured, or wherein the base coat is not fully cured but gelled if a further top coat is applied onto the base coat;g. applying an optional top coat, wherein the top coat is a clear coat or comprising 3-8% by weight pigment; andh. applying UV light to the optional top coat and curing the top coat fully.

37. The method according to claim 36, characterised in that the top coat is cured using an LED UV light source with a dual wavelength of 405nM (front zone deep cure) and 365nm (back zone top cure).

38. The method according to claim 36 or 37, characterised in that LED UV light source comprises multiple sections of higher / lower intensity and / or higher / lower wavelength to cure the coating layer, wherein the coatinglayer is cured first by UV light emitted by the higher intensity and / or wavelength section.

39. The method according to claim 38, characterised in that the UV light has a higher intensity between 4000 mW / cm2 and up to 16000 mW / cm240. The method according to claim 38, characterised in that the UV light has a lower intensity between 2000 mW / cm2 up to 3000 mW / cm2.

41. The method according to claim 38, characterised in that the UV light has a higher wavelength in the range of 405 nm.

42. The method according to claim 38, characterised in that the UV light has a lower wavelength in the range of 365 nm.

43. The method according to any of claims 36 to 42, characterised in that the surface marker comprises a power supply (3) of at least 2000 W.

44. The method according to any of claims 36 to 43, wherein steps b and c are repeated several times to apply and gel-cure one to three layers of primer45. The method according to any of claims 36 to 44, wherein the base coat as top coat is cured using an LED UV light source (4) with a dual wavelength of 405nM (front zone deep cure) and 365nm (back zone top cure).

46. The method according to any of claims 36 to 45, characterised in that the primer is a clear coat without pigments.

47. The method according to any of claims 36 to 46, characterised in that a UV top coat is applied and cured as a protective UV coat over an existing base coat.

48. A surface marking for outdoor surfaces applied by a surface marking system according to any of claims 1 to 44, or by a method according to any of claims 45 to 62, characterised in that the surface marking comprises a paint composition adapted for curing by exposure to UV light, the paint composition comprising:a. one or more multifunctional acrylate oligomers in a concentration of 25 to 45% by weight;b. one or more high molecular acrylic binders for enhanced adhesion and flexibility with a molecular weight Mn 10.000-20.000 Daltons: 1 to 5% by weight;c. one or more multi and / or mono-functional monomers in a concentration of 20 to 45% by weight;d. a main photo initiator in a concentration of 1 to 5% by weight;e. one or more alternative or supplementary photo initiators for different UV light ranges in a concentration of 1 to 5% by weight.

49. The surface marking according to claim 48, characterised in that the paint composition further comprises:a. a polymerisation inhibitor or stabilizer for radically curable resins in a concentration of 0,1 to 0,5% by weight;b. one or more polymeric, silicone-free and silicone containing flow and levelling agents for better substrate wetting in a concentration of 0,1 to 1,0% by weight;c. one or more defoamers based on organic polymers, silicone free and silicone based to prevent air entrapment in a concentration of 0,1 to 3,0% by weight;d. a hindered amine light stabilizer (HALS) to reduce degradation by sunlight in a concentration of 0,1 to 1,5% by weight;e. one or more pigments for color and opacity in a concentration of 0,5 to 5% by weight;f. one or more fillers / extenders for opacity and mechanical properties in a concentration of 15 to 25% by weight;g. one or more adhesion promoters for better adherence to substrates in a concentration of 0,5 to 1,5% by weight; andh. one or more rheology modifiers based on hydrophobic pyrogenic silica for optimal flow, leveling and sedimentation in a concentration of 0,1 to 1,5% by weight.

50. The surface marking according to any of claims 48 or 49, characterised in that the surface marking comprises a primer, a base coat and an optional top coat.

51. The surface marking according to claim 50, characterised in that the primer has a thickness of 0-200 pm and a concentration of pigment of 0-10% by weight, preferably 0-4% by weight.

52. The surface marking system according to claim 50, characterised in that the base coat has a thickness of 0-400 pm and a concentration of pigment of 0-10% by weight, preferably 5-8% by weight.

53. The surface marking system according to claim 50, characterised in that the top coat has a thickness of 50-250 pm and a concentration of pigment of 0-10% by weight, preferably 0-5% by weight.

54. The surface marking according to any of claims 48 to 52, characterised in that the pigment is titanium dioxide.

55. The surface marking according to any of claims 48 to 53, characterised in 5 that the surface marking comprises a top coat applied on an existingbase coat.

56. The surface marking according to any of claims 48 to 54, characterised in that the surface marking is a line marking for an off-highway or indoor 10 surface.

Images