Water streaking in bold type and solids.

[Ajax]

We're running a job with a light gray the consists
primarely of transparent white. How ever it seems
like there is way too much pigment. If you so much
as wave an ink knife over your rollers its way too dark.

Getting the color right during make ready is a pain. It
washes out with water streaking for 50 sheets and after
that it will tone in almost like clock work. There is barely
a film of ink on the rollers. The keys are basically closed
and the strip at 15 percent.

This is a toyo ink and a one step fountain solution. Rollers
are adjusted to specs and there aren't issues with other
inks in that unit.

What are your thoughts?

 

[M.P.Walinga]

Dear Ajax,

Could you be more specific about the color, What I would like to know is what kind of gray you are printing. Depending on the tone of gray it sometimes helpes to mix op a silver inkt in to the gray. This wil reduce the streaking and water in the ink.

 

[nhprinter]

Have you tried just adding more trans white so you can run more ink?

 

[Kaoticor]

Out of normal colors (especially metallics) dont really react well with normal press chemistry. If you are confident in the quality of your print unit and you see it in other units too, then you are probably right, it is just how that ink reacts...
You can "standardize" and "optimize" your machinery as much as you can, but some jobs will still never give in!

Something that we did when running really troublesome, cheap, metallic inks was to start out our water feed at almost nothing when beginning the job. (I'm just sharing my experience, not necessarily recommending this!). You can keep a close eye out for catch-up and slowly bring your water up untill you find that minimum balance, which will be a lot different than normal process color inks. This helped us with the excess wash-out at startup. We just had to start out with too little water or the ink never seemed to be right. Guess thats what we get for purchasing metallics to the lowest bidder...

 

[Ajax]

This is pms 432. We have 40lbs for the job and
4 cans that we opened act the same. We have been
adding transparent white at a 30-40 percent ratio.

Its more manageable but it seems like the ink should
have arrived that way in the first place. Now we have
to bite the cost of transparent white.