Pigment Red 57:1 for water based inks P.R.57:1 is known under a variety of names, the most common among which is 4B toner. P.R.57:1, the calcium salt, ranks high among organic pigments in production volume and use. The pigment is used primarily in printing inks. Its shade matches the standard magenta of a number of color scales for three and four color printing. P.R.57:1 is found in all types of printing inks. Like with other pigment lakes, however, there is a certain possibility that storage problems may arise, a fault which is independent of the resination of a pigment. The viscosity of an alkaline printing ink often increases more or less upon storage, The different grades of P.R.57:1 vary considerably, not only in their coloristics but also in their rheological behavior. Individual grades are frequently optimized for special printing inks, for instance for publication gravure inks.