Three Important Functions of CtP

[printPlant]

Hi. Please teach me.
What is the purpose and function of "Light Time, Developing Time, Developing Temperature" in CtP and its Developing Processor. Please describe in detail....

 

[VladCanada]

Are you banned at google or Wikipedia?

 

[printPlant]

Are you banned at google or Wikipedia?

I had tried many keyword on google and wikipedia but no such results i found.
Please give me some keywords for this purpose that i can search on google or wikipedia.
or provide me some material that clear my concept about this processes.
many thanks

 

[VladCanada]

"offset plate developing process" at google, for instance...
or printpedia.inf
The ability of asking correct question contents 50% of correct answer(C)

 

[printPlant]

Many thanks for these keywords i found some material.
one question i ask you that i expose the grey wedge on the CtP. Please tell me how i can measure the plate dip time for this wedge.

 

[VladCanada]

Contone control wedges like STOUFFER or UGFA/FOGRA are not related to developer time of plates, just for correct CTP exposure value as a coarse approach, and dont work for Thermal and Lithostar plates but for Photopolymer ones.
You have to follow recommended plate processing parameters like Temperature, DEV Time and Dwelling (brush scrabing) time.
Analog (conventional) plates at UV setters like BasysPrint is another well known story, similar to exposure control procedure for UV contact frames. (and not for dip time as well).

 

[printPlant]

That's it!
Everything is clear with this Golden Line

"You have to follow recommended plate processing parameters like Temperature, DEV Time and Dwelling (brush scrabing) time".

Thanks

 

[printPlant]

One more question in my mind please clear it.

I use Basysprint UV-Setter 1500dpi and positive plate use IPAGSA.

How the wedge final? from Light Time or Dwell Time.
1. If Dwell Time keeps constant as per the Plate manufacturer standards and changes in the Light Time
for gain the desire result.
or
2. If Light Time keeps constant and changes in the Dwell Time for gain the desire results.

Which one i select in both of them #1 or #2 or best quality standard in your mind.

 

[VladCanada]

After control wedge on the plate is exposed and developed, you have to look at the result for your judgement:
some steps should be solid, some wipped off and some "partly damaged" or "foggy".
If dwell time is too much (or brush-rollers pressure is too high, or brush speed is too high), you will remove all "foggy" wedge steps.
So, how you will make your judgement?
So, extra dwell time will not only decrease the printing elements size (dimension), but a thikness of emulsion layer.
You will get a shorter plate run on the press and blinding, small % dot loss.

My advice: keep the processor parameters stable and within recommended min/max threshold.
Vary only variable parameters (ligh time or exposure) to get the result as predictable.

I hope Gordon Pritchard gonna drop his "5 cents" when he will find a few minutes during or after Canada long weekend

 

[printPlant]

thank you very much...