High-intensity LED UV curing and surface marking system

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

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), a 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 700 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 a coating layer having a thickness of 300-400 pm in a single pass.

14. 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 a coating layer having a thickness of 400-700 pm in a single pass.

15. The surface marking system according to any of the previous claims, characterised in that the coating layer comprises a concentration of pigment of 2-10% by weight, preferably 2-8% by weight.

16. The surface marking system according to any of the previous claims, characterised in that the coating layer comprises a concentration of pigment of 0.1-4% by weight, preferably 0.1-2% 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 or a highway road or any other outdoor surface.

19. The surface marking system according to any of the previous claims, characterised in that the power supply (3) is either a full battery system comprising one or more rechargeable power stations or a hybrid system comprising one or more rechargeable power stations in combination with an engine-driven alternator (13), with an optional recharging of the power stations by the alternator during use of the system.

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 to 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, suchas 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 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 adjustmentsystem (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 further comprises a dispenser (9) for dispensing optically transmissive components, the dispenser configured in between the paint applicator (6) and the LED UV light source (4).

34. The surface marking system according to claim 33, characterised in that the dispenser (9) is configured to drop retroreflective optically transmissive components on the surface of a coating layer before UV curing.

35. The surface marking system according to claims 33 or 34, characterised in that the optically transmissive components comprise coated optically transmissive components.

36. The surface marking system according to any of claims 33 to 35, characterised in that the optically transmissive components comprise partially coated optically transmissive components.

37. The surface marking system according to any of claims 33 to 36, characterised in that the optically transmissive components comprise a mix of non-coated and coated optically transmissive components.

38. The surface marking system according to any of claims 33 to 37, characterised in that the optically transmissive components comprise micro beads, such as glass or quartz beads, and / or angled glass particles.

39. The surface marking system according to any of claims 35 to 38, characterised in that the optically transmissive components are coated with a concentration of titanium dioxide of at least 30% by weight, preferably at least 45% by weight, more preferably at least 60% by weight.

40. The surface marking system according to any of claims 35 to 39, characterised in that the coating of the optically transmissive components comprises 1-10 g of titanium dioxide for every 100 grams of optically transmissive components, preferably 2-6 g, ensuring full coverage and maximum retroreflectivity.

41. The surface marking system according to any of claims 35 to 40, characterised in that the coating of the coated optically transmissive components is abradable.

42. The surface marking system according to any of the previous claims, characterised in that the system is a 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, a LED UV light source (4) comprising a UV protective shroud (19) surrounding the LEDUV light source, and at least an exchangeable and / or reloadable battery power station (3).

43. The surface marking system according to claim 42, characterised in that the mobile unit is operated by a human operator or remotely controlled.

44. The surface marking system according to claim 42 or 43, characterised in that the system components are modular and scalable depending on the size of the mobile unit.

45. 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 UV paint, an optional dispenser for dispensing optically transmissive components; and a 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 UV paint to the surface in a coating layer having a thickness of up to 700 pm;c. optionally dispensing optically transmissive components in and / or onto the coating layer;d. applying UV light to the coating layer and curing the coating layer in a single pass.

46. The method according to claim 45, characterised in that the LED UV light source comprises multiple sections of higher / lower intensity and / or higher / lower wavelength to cure the coating layer, wherein the coating layer is cured first by UV light emitted by the higher intensity and / or wavelength section.

47. The method according to claim 45 or 46, characterised in that the UV light has a higher intensity between 4000 mW / cm2 and up to 16000 mW / cm248. The method according to claim 45 or 46, characterised in that the UV light has a lower intensity between 2000 mW / cm2 up to 3000 mW / cm249. The method according to any of claims 45 to 48, characterised in that the UV light has a higher wavelength in the range of 405 nm.

50. The method according to any of claims 45 to 48, characterised in that the UV light has a lower wavelength in the range of 365 nm.

51. The method according to any of claims 45 to 50, characterised in that the surface marker comprises a power supply (3) of at least 2000 W.

52. The method according to any of claims 45 to 51, characterised in that the optically transmissive components comprise coated optically transmissive components.

53. The method according to any of claims 45 to 51, characterised in that the optically transmissive components comprise partially coated optically transmissive components.

54. The method according to claims 52 or 53, characterised in that the coated optically transmissive components are applied or dropped onto the surface of the coating layer.

55. The method according to any of claims 45 to 54, characterised in that the optically transmissive components comprise micro beads, such as glass or quartz beads, and / or angled glass particles.

56. The method according to any of claims 45 to 55, characterised in that in step b a mix of coated optically transmissive components, preferably 60% by weight, and standard optically transmissive components, preferably 40% by weight, are dispensed.

57. The method according to any of claims 45 to 56, characterised in that the optically transmissive components have a size of 200-850 micron.

58. The method according to any of claims 45 to 57, the method comprising the steps of:a. applying a coating layer having a thickness between 400 and 700 micron with a paint comprising 0.1-4% by weight pigments;b. dispensing drop-on coated optically transmissive components onto the surface of the coating layer;c. curing the coating layer using a LED UV light source (4).

59. The method according to any of claims 45 to 57, the method comprising the steps of:a. applying a coating layer having a thickness between 300 and 400 micron with a paint comprising 2-10% by weight pigment;b. optionally dispensing drop-on coated optically transmissive components onto the surface of the coating layer;c. curing the coating layer using a LED UV light source (4).

60. The method according to any of claims 45 to 57, characterised in that the coating layer is a clear coat without pigments.

61. The method according to claim 58 or 59, characterised in that the drop-on coated optically transmissive components are embedded in thecoating layer to a depth of approximately 40-60% of their volume and have a size between 150-650 micron.

62. The method according to any of the previous claims, characterised in that the coating layer is a top coat applied on an existing base coat.

63. 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 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 photoinitiator in a concentration of 1 to 5% by weight;e. one or more alternative or supplementary photoinitiators for different UV light ranges in a concentration of 1 to 5% by weight.

64. The surface marking according to claim 63, 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.

65. The surface marking according to claim 63 or 64, characterised in that the paint composition further comprises optically transmissive components.

66. The surface marking according to any of claims 63 to 65, characterised in that surface marking is retroreflective and comprises coated optically transmissive components exposed on the surface of the coating layer.

67. The surface marking according to any of claims 63 to 66, characterised in that the optically transmissive components are partially coated.

68. The surface marking according to any of claims 63 to 67, characterised in that the optically transmissive components comprise coated and noncoated components.

69. The surface marking according to any of claims 63 to 68, characterised in that the optically transmissive components are micro beads, such as glass or quartz beads, and / or angled glass particles.

70. The surface marking according to any of claims 63 to 69, characterised in that the coating layer has a thickness between 400 and 700 micron and a concentration of pigment of 0.1-4% by weight, and comprises drop-on coated optically transmissive components on the surface of the marking.

71. The surface marking according to any of claims 63 to 69, characterised in that the coating layer has a thickness between 300 and 400 micron and a concentration of pigment of 4-8% by weight, and optionally comprises drop-on coated optically transmissive components on the surface of the marking.

72. The surface marking according to any of claims 63 to 71, characterised in that the surface of the surface marking exposes coated optically transmissive components.

73. The surface marking according to any of claims 63 to 72, characterised in that the pigment of the coating layer is titanium dioxide.

74. The surface marking according to any of claims 63 to 73, characterised in that the pigment of the coating of the optically transmissive components is titanium dioxide.

75. The surface marking according to any of claims 63 to 74, characterised in that the UV curable coating layer is a top coat applied on an existing base coat.