BLUING OF WHITE PLASTICS.

Apart from a fine-particle titanium dioxide pigment of rutile crystal modification, an addition of bluing agent and/or fluorescent whitening agent is required if a bluish white tone is to be obtained in plastics. Investigations are made into the influence of progressively increasing proportions of such additives on the brightness, undertone and opacity of white polyethylene and PVC film. The practical application of the resulting findings are shown by means of a color matching example. For figures and literature see German text.