Ukiyo-e prints of the early 17th century developed from illustrated books. Later in the century the illustrations gained such widespread popularity that they were issued separately. Early ukiyo-e prints were printed in black and white, sometimes with red, yellow and green colour washes added by hand. With the advent of full-colour printing in the 1740s, up to ten colours could be applied, each by its own carved woodblock. Improved printing techniques made the vibrant and colourful ukiyo-e prints one of the great achievements in Japanese art. The ukiyo-e format inspired Japan's greatest artists. The radical perspectives, flat planes of colour, and bold lines of Utamaro, Hokusai, Hiroshige, and other ukiyo-e masters were much admired in the West and considerably influenced the works of Impressionist and post-Impressionist painters such as Manet, Whistler and Van Gogh.