- Iriodin effect pigments play an important role in the finishing process.
- The pearlescent effect which is created through them has a big benefit.
- Pearlescent effects are used for prints of jewellery, cosmetics, cars or metal.
- Pearlescent varnishes have the advantage that they can be applied through the ink unit.
- The use of the more complex coating unit is therefore not necessary.
Handling advice for pearlescent varnishes
- The pH value of the fountain solution should not be higher than 5 as this can lead to problems in the colour transmission or to an enrichment of the pigments in the fountain solution.
- The damping has to be reduced close to the point where the varnish starts marking.
- An increase in the thickness of the ink film leads generally to the intensification of the pearlescent effect.
- As the ink film in offset printing is thin, there will be a proportionally small amount of effect pigment applied on the printing substrate. In the ideal case the varnish should be applied via two printing units.
- The Iriodin should be mixed up before being used as pigments can depose to the bottom of the tin.
- When using pearlescent varnishes the transfer through the blanket onto the printing substrate plays a critical role. Therefore a rubber blanket that avoids fast build up of pigments on the blanket is recommended. Besides a special Iriodin blanket, e.g.:
of the company Reeves you can also use conventional blankets (with possible limitations). Good results for example were obtained with the following blankets:
„Phoenix − Topas ®“
„Contitech − Ebony®“
„Sumiomo − ST 800®“
„Kinyosha − S7400®“
„Day International − Graphica 3000®“
„Sava − Advantage New ®“
This technical instruction sheet is designed for your information and reference. It is based on and conforms to our current knowledge. However as actual application is affected by many factors over which we have no control, we are not liable for printing failures.