UV varnish issue

[janezl]

I wanted to put UV varnish on the cast coated board. Using Sun Chemical Hy brite UV and 80 lpi screen roller on Roland 700, I got grainy surface instead of smooth and glossy one.
Too high surface tension of varnish?

Any hint for another UV varnish?

Janez

 

[Rhino]

The "graininess" could be caused by multiple variables such as contamination of the coating and/or board, application, etc.

If you're looking for an outstanding high gloss UV coating with NO ODOR then I would recommend RhinoFlexx-1632 from Rhino.

Go to their website for contact info: Welcome To Rhino Performance Products

 

[Colornumber9]

Could be a stock issue

Could be a stock issue

I recently ran into a similar problem on a cast coated sheet, and it turned out to be the stock. For whatever reason the coating (I tried both of our UV coatings) wouldn't lay down smooth and the gloss level was significantly less than normal. We ended up putting a layer of UV sizing varnish (you can also try transparent white or other UV varnishes) down to seal the sheet before coating and it resolved the issue.

This might not be your problem but it would probably be easier and cheaper to try than changing your consumables.

 

[Sun MF]

Janez,

I have a suggestion from Sun Chemical if you're interested. Let me know and I'll send an email.

 

[janezl]

Sun MF, send me PM

Janez

 

[mfallona]

Cast coated papers are much more absorbant than ordinary clay coated paper. Lower viscosity inks or varnish will often sink into the paper giving a washed out or grainy appearance. Increase your viscosity or cell size.