What is the difference between 油漆, 涂料 and 油彩 please?
油画: oil paint (the artwork or 'painted canvas')

油画颜料/油性颜料: oil paint (the painting material)

油彩: grease paint (the painting material, for artwork or cosmetics)

水彩: water color

颜料: paint (materials in general, usually refers to that for artworks) 

涂料: paint/coating (materials in general, usually refers to that for industrial purposes such as painting a house)

油漆: oil-based paint (usually refers to that for industrial purposes)