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View Full Version : Jo Sonya Polyurethanes -- How Non-Yellowing; Fine Art Use?


Nilesh
07-02-2010, 07:38 PM
Hi Jennifer,

Jo Sonja's Polyurethane Water Based Varnishes are described as non-yellowing and lasting. What I am trying to find out is what kind of testing has been done to determine this, or what other reasoning or evidence is behind this? How do these varnishes compare with the acrylic varnishes (the varnishes used for Interactives, say) in archivalness, or rate of yellowing, aging characteristics, or longevity? Do these polyurethane films hold up as well as the acrylic films, in terms of aging?

These are important issues for me, and I am trying to find some sort of scientific evidence, accelerated aging, weathering or UV-exposure test data, etc.

Thank you.

jennifervs
08-05-2010, 09:09 AM
Hi Nilesh,

The Jo Sonja Varnishes are indeed non-yellowing and applied correctly, will hold up as well as well as the Atelier Water-Based Finishing Varnishes, but there are differences: Jo Sonja's Polyurethane Water-Based Varnishes will be tougher and more rigid from the polyurethane, as would be practical for a paint and varnish system primarily designed for the decorative arts market, which historically paints on hard surfaces. Atelier Medium & Varnishes provide a protective acrylic coating that is more flexible, which would be practical for fine artists that paint on paper or canvas that needs to be rolled. As a manufacturer, we purchase the components for our products from top suppliers who independently test the ingredients for lightfastness, non-yellowing, strength, flash point, etc. Chroma's own testing is real-time, done by artists who sample materials for us in a variety of circumstances. To date (over 20 years) we have not had single complaint that any properly applied Jo Sonja Polyurethane Water-Based Varnish or Atelier Medium & Varnish has yellowed.