polymers for use in marking ink

[larsbentley]

I am doing some experiments in ink chemistry, trying to formulate a basic marking ink. I'm not chemist. I tested out some polymers dissolved 5% by weight in ethanol for use as the resin (PVB and CAB) and applied them to plastic and glass surfaces to see how they act. I was expecting both to form a glossy transparent film (desirable) but neither did so, instead forming a dull milky white film. Does anyone have any advice on why this is happening or additives needed to form a clear film?

Thanks much