Search for "colored notebooks" and you'll find covers: red, green, yellow, all with the same white pages inside. Color in the page itself is a different thing, and it has more history than you'd expect.
Six hundred years of blue paper
Blue paper has been made in Europe since the Middle Ages, from pulped blue rags. A Bolognese statute of 1389 already regulates it, and in 16th-century Venice Carpaccio, Titian and Tintoretto all used it. Albrecht Dürer used it during his stay in the city: in 1506 he drew a saint's hands on it, in grey ink with white heightening. The reason was technical. A blue sheet gives you the middle tone from the start, so the artist only adds the shadows and the lights. In 2024 the Getty Museum in Los Angeles gave it a whole exhibition.
Blueprints and a purple accident
Blue paper had a second life in 1842, when John Herschel invented the cyanotype. From the 1870s to the mid-20th century it was the way plans were copied, white lines on a blue ground, which is where the word blueprint comes from. Purple has its own story. For centuries it was the most expensive dye there was, made from sea snails, until in 1856 an 18-year-old student, William Perkin, made a purple dye by accident in his home laboratory while trying to synthesize quinine. It was the first synthetic dye ever sold, and it made mauve fashionable.
What exists today
There are three families. Toned papers for artists, in grey, beige or black, sold as pads and spiral sketchbooks and used for studying light and shadow. Pastel-paper notebooks, common in Japanese stationery, where the color is so soft you write with any pen. And saturated ones, which are few: notebooks where the page really is black, blue or red and you write in light ink.
How to tell if the color is real
Look at the edge. If the paper is dyed, the edge of the notebook is the color of the pages. If it's only printed on the surface, the edge looks white, and tearing a corner shows a pale core.
What changes when you write
On a pastel page, nothing. On a saturated one the ink changes: ballpoint ink is transparent and gets lost, so you use light, opaque inks, with white as the base. In exchange, something curious happens to the other colors. On a dark page a pale yellow, a turquoise or a light pink stay very visible, while a dark blue or a brown go quiet. Choosing the color of the page is also choosing your palette. Here's the pen guide.
Ours
Bocetta belongs to the third family. Each notebook is one color all the way through: cover, pages, edges and ribbon. Nero (black pages) and Blu (cobalt blue pages) are available now; Rosso (red pages) and Viola (purple pages) are coming soon. All of them measure 17.6 × 24.5 cm, have 160 blank pages of 120 g/m² paper and come with a white gel pen.
If you can't decide, the color quiz takes a minute. And if you'd like to see them together, here are all the colored paper notebooks.
Sources: the University of St Andrews exhibition Venice in Blue, the Getty Museum on Drawing on Blue, the Getty Conservation Institute's cyanotype atlas and the Science History Institute on William Perkin.