Automatic Processes

The automatic sorting of letters and parcel post is an appropriate example of automatic processes. The signal for the necessary alignment of the mail is emitted by luminescent pigments added to the stamp ink or the printing inks used in franking machines. The aligned letters and parcels can be printed with the post al-code or their destination in the form of a luminescent line code. This code gives a signal to a sensing device on the sorting machine.

Fluorescent as well as phosphorescent pigments are used for stamps and code tapes. Phosphorescent materials have the advantage that excitation and sensing can be carried out at separate points.

Lumilux® pigments are based on a variety of "host lattice" chemistries. Zinc sulfide-based pigments, rare earth-doped strontium aluminates, rare earth oxide sulfides, alkaline earth sulfides, silicates, tungstates, hexa- aluminates, phosphates and a pool of organic heterocyclic compounds form the basic chemistry of the Lumilux® product line.

Zinc sulfide-based pigments have been around for decades and bring many advantages to the processes that utilize them. They demonstrate good fading resistance under indoor conditions and their grain size distribution parameters are adjusted to the most important processing methods. They show very good fluorescent brightness performance, good initial afterglow brightness performance and very uniform batch-to-batch consistency. For these reasons, they hold an important place in the Lumilux® product family.

By using Lumilux® luminescent pigments with selected fluorescent and phosphorescent properties, special excitation characteristic, optimized grain size distribution and high signal strength, the wide range of Lumilux® fluorescent and phosphorescent materials makes it possible to offer custom tailored marking properties for most application problems.

Honeywell Specialty Materials can produce customized luminescent pigments to customer's specification.

For further information, please contact us.