subject: Synthesis Ultramarine Blue Pigments For Plastic, Master Batch And Other Industries [print this page] Synthesis Ultramarine blue pigment is a very safe, non-hazardous blue pigment with a variety of applications worldwide. Its synthetic manufacturing process and possibility for close control over its physical, chemical, and color characteristics enable the production of several types of this blue pigment, which are readily accepted by plastic, printing ink, food contact package, paint, cosmetic and many other industries due to advantages over other organic pigments and dyes. Besides, Ultramarine blue is an environment friendly pigment available to the industries.
The main contaminant which may be present in a plastic master batch based on Ultramarine pigment is sulfide. There are two possible reasons for its presence.
Firstly, Ultramarine pigments contain sulfur chromophores, plus small quantities of un-reacted sulfur. These un-reacted species are volatile at plastics processing temperatures and are released as sulfides. Normally the amount of free sulfur present even in the general purpose grades manufactured by Holliday Pigments is not enough to cause any objectionable taint or odour as it is removed along with the other volatiles such as moisture during the production process.
However, food contact plastics are especially sensitive to taint and for these applications even well processed standard grades may not be pure enough. For that reason Holliday Pigments Premier BC ranges for severely demanding food contact applications are free from un-reacted sulfur and superior performance is ensured by improving the specification for volatiles to 0.05% maximum at 150c (standard grades are tested at 105c) and the un-reacted sulfur to 20ppm maximum (standard grades 200ppm). After thorough independent testing of bottle caps cloured with this grade and immersed in pure mineral water, no evidence of taint in the water could be detected.
Secondly, Ultramarine is sensitive to attack by acids which release sulfides. Such acids may be present as breakdown products of the polymer (such as PVC) or in some foods (sparkling mineral water and fruit juices). While the polymer may protect standard grades of Ultramarine against such weak acids for a period, it is much better to use an Ultramarine which has its own protective coating to resist such attack.
Abelly chemical is the leading manufacturer of synthesis ultramarine blue pigments in china which is widely used in master batches, plastic, pvc, pp, pe, paint and coating, food contact packaging and other industries.
