Bleaching agent, preparation and use of the same with polymerizable compositions for optical materials

A polymerizable composition for an optical material comprising:

• (A) a polymerizable component comprising an aromatic ester compound including two or more allyloxycarbonyl groups,
• (B) a colouring component comprising particles of a blue pigment (b1);
• (C) a polymeric dispersing agent to disperse the particles of the colouring component (B) in the polymerizable component (A);
• (D) an ultraviolet absorbing agent;
• and
• (E) a radical polymerization initiator,
• wherein the particles of the colouring component (B) have a z-average size equal to or lower than 400 nm, as measured by Dynamic Light Scattering technique according to the method ISO 22412:2017, and
• the polymeric dispersing agent (C) comprises a polymeric part and one or more pigment affinitive-groups selected from:
• carboxylic group, sulphate group, sulphonate group, amine salts, phosphate group, phosphonate group, carbamate group, urea group, amide group or amine group.