ADDITIONAL INFO:

How to make printing plates with exposure unit

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Laser Engravable Plates

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How to Make a 1 Mil Alcohol Wash
Printing Plate: Step by Step Instructions

Procedure for making printing plates

1. Roll up vacuum blanket on UV exposure unit
2. Remove the protective cover sheet from photopolymer plates
   
3. Inspect the surface of printing plates for spotting or other visual defects
4. Center the plate on the platen metal side down
   
5. Place the film positive (emulsion side down) on the plate and center it on the plate
6. Turn on the vacuum and drape the vacuum blanket over the film/plate combination. Wipe the vacuum blanket smooth to ensure there are no air pockets trapped or creases in the blanket.
7. Once achieving a steady vacuum of 22 inches Hg., close the UV exposure unit and set the exposure timer according to the Table below (Please note that exposure times will vary with different exposure units):
   
   

   Film Exposure	Screen Exposure	Screen Size	Depth of Etch
   60 Seconds	60 Seconds	200/90	1 Mil
   90 Seconds	90 Seconds	300/90	1 Mil

   
   
8. Verify that the vacuum gauge has a steady reading and start the timer sequence
9. After the completion if the timed sequence and vacuum has shut off, slide out the drawer (or open the lid) and roll back vacuum blanket
   
10. Remove the film positive from the printing plate
    
    Second Exposure:
    
    
11. Place the halftone screen film on the plate emulsion side down
    
12. Turn on the vacuum and drape the vacuum blanket over the film/plate combination. Smooth out vacuum blanket to ensure there are no air pockets trapped under the vacuum blanket and creases in the blanket
    
13. Once achieving a steady vacuum of 22 inches Hg., close the UV exposure unit and set the exposure timer according to the Table 1
    
14. Verify that the vacuum gauge has a steady reading and start the timer sequence
15. After the completion of the timed sequence, slide out the door (or open the lid)
    
    Developing Printing Plates:
    
    
16. Remove the plate from the UV exposure unit
17. Using a printing pad soaked in alcohol wash developer solution rub gently to washout the uncured material from the plate for about a minute
18. Neutralize the developer solution by spraying the plate with a light mist of fresh, warm water
    
19. Gently blow dry both sides of the plate with clean, filtered air
    
    Post Exposure:
    
    
20. Open the UV exposure unit and place the printing plate on top of the platen. Do not cover the plate with the vacuum blanket
    
21. Post-cure the printing plate by setting the UV exposure time for 10 minutes. The post-cure ensures plate longevity by fully curing the etched area and surrounding material.
    
22. Place the plate into a convection oven preheated to 140 degrees F for 8-10 minutes
23. Remove the printing plate from the oven. Allow to cool down to room temperature.
    

Important notes about making printing plates

• The first exposure time on the film positive determines the overall depth of the ink well. The SHORTER the exposure time the deeper the printing plate.
• The second exposure on the film positive determines the amount of ink, the size of the dot and the spacing between the dots.
  
• Reducing the 2nd exposure time on the screen will reduce the height of the dot and will let more ink transfer
  
• You can control the printing effects by varying halftone screens:
  
  • A 300 line screen will print finer graphics with shallower printing plates.
    
  • A 200 line screen will print medium graphics and medium depth printing plates.
    
  • A 150 line screen will print course graphics and with deeper printing plates.
    

Make a beautiful print!