Computer to plate teen work and their working offset printing

1. COMPUTER TO PLATE
(CTP)
Thrd mdl

2. CTP
 The word CTP defines master of image
transferring techniques.
 It is the imaging technology used in modern
printing process.
 It use laser beams to directly write images on
to the printing plate rather than , first exposing
a film then transferring the image to the plate.
 The digital direct plate imaging method
eliminate trouble some film process.

3. ELEMENTS OF CTP;
CTP – DESIGNS
• There are three basic design for CTP ;
1. External drum
2. Internal drum
3. Flatbed
Imaging system

4. TYPES

5. EXTERNAL DRUM DESIGN- CTP

6. EXTERNAL DRUM DESIGN ;
 In an external drum plate setter , the plate is
mounted on the outside of the drum .
 As the drum rotate on its axis , a multiple laser
beam head moves parallel to the drum and
burns the image on to the plate .
 Mostly , using for the imaging of the
flexographic plate .
ADVANTAGES ;
 Shorter imaging time
 Easy plate handling

7. INTERNAL DRUM DESIGN - CTP

8. INTERNAL DRUM DESIGN ;
 In an internal drum plate setter , the plate is put in
to a cylinder .
 As the imaging head moves along the axis of the
cylinder to expose the plate .
 A single laser beam writes the digital image on to
the fixed plate .
 The laser beam is projected on to a spinning
mirror that rotates at a very high speed .
 It has longer imaging time than external drum CTP

9. ADVANTAGES ;
 Uniform beam intensity
 Stationary printing plate
 Greater accuracy

10. FLATBED DESIGN - CTP

11. FLATBED DESIGN CTP
 In the flatbed plate setter , the image is reproduced
line by line on a fixed flat printing plate by a laser
beam the is deflected by a rotating polygon mirror
and then on to the printing plate .
 Mostly , using for the offset printing plate
(newspaper printing).
ADVANTAGES;
 Easy handling of plate
 Used by quality devices
 Shorter imaging time