It’S invisible but can show visible color under the 200-400nm UV light.It can be divided into long wave(365nm),short wave(254nm)and double wave according to its wavelength. Color: Long wave:Invisible-yellow,orange,red,yellow green,emerald green,grass green,blue, reddish blue,black,white,blue green Red to orange,red to red,green to grass green,blue to grass green, orange to red,yellow to red,Black to red,black to green… Short wave:Invisible-yellow,orange,red,green Double wave:Long wave red—Short wave green, Long wave blue—short wave red,yellow,orange,green Long wave grass green-Short wave yellow,orange,red Printing way:Offset,UV offset,Letterpress,UV letterpress,UV flexo,Silkscreen, UV silk screen,Water-based silk screen,Water-based flexo,Gravure…