Vignettes and gradients in Package Printing

[Johnsonaaro]

Thanks for reading.
I work for a gravure food packaging printer and recently we have had a few designs come through which have been frustrating.

One design has a background that is - Blue Line color on top, black on the bottom, transitions from blue to black in a 2" area in the middle.

Both colors are on their own layer.

substrate is white.


How would you build this background?


colors vignetting into each other? coverage has to be full so that the white substrate doesnt show through or wash out colors.


solid blue background with black overprinting? blue cant show through the black because there are other flavors built the same way and the blacks from each need to match.

also


how would you build the vignette in illustrator? any slider points added to control the opacity will result in banding when it prints


I appreciate any help I can get!

Thanks,
Aaron

 

[WI-Flexo]

Couple ways to accomplish this. One way like you said is to have the black overprint the blue. This way you get a nice rich black and get no hollow area where the colors overlap. Also like you said, the other items need to match. So if the blue is the "flavor" color just use whatever the flavor color is to under color the black. The other option that we use all the time is to adjust the gradients so they do not drop off in the same area but overlap by a bit. So the center area has a substantial dot from each color. I am attaching a PDF that somewhat shows what I am talking about. Bad "hollow" overprint on top and better overprint on the bottom. Could always take a look at the actual file if you would like.

 

[Karl Jennex]

I use Photo Shop, I start with a 1/c solid bar, blur and add noise. Use that as a selection, invert and fill. Then size either side so they dont break at the same place just like WI-Flexo does.

Also the more channels used in the vignette the smother it is, so a 4 color vignette is smother than a 2 color.