Large quantities are used in the manufacture of paper, and especially for producing a kind of pale blue writing paper which was popular in Britain. During World War I, the RAF painted the outer roundels with a color made from ultramarine blue. This became BS 108(381C) aircraft blue. It was replaced in the 1960s by a new color made on phthalocyanine blue, called BS110(381C) roundel blue.
Large quantities! are used in the manufacture of paper, and especially for producing a kind of pale blue. writing paper which was popular in Britain. During World War I, the RAF painted the outer roundels with a color made from ultrama?rine blue. This became BS 108(381C) aircraft blue. It was replaced in the 1960s by a new color made on: phthalocyanine blue, called BS110(381C)? roundel blue.