Stamp

PROCESS

Typesetting

Typesetting for photopolymer stamp

Typesetting on computer
Required software : Illustrator, Xpress, Corel Draw, Freehand…
Required equipment : PC or Macintosh
Positive film printing
Required product : tracing paper
Required equipment : 600 to 1200 dpi laser printer

Photopolymer processing

Negative exposure for polymer stamp

1 - A negative film is produced
Product : day light film, developer, fixer

Preparation of resin stamp

2 - All components are arranged :
Products : substrate sheet , damming tape, coverfilm, polymer resin

Front and back exposure of photopolymer stamp

3 - The back part is exposed to form a solid base 
Then, the front part is exposed : the areas where UV light can pass through the negative harden and create the relief image

Photopolymer washing

4. The photopolymer material is washed
Product : wash-out solution

Post exposure of photopolymer stamp

5. Then, the photopolymer plate is exposed again to UV light, to complete the curing process 
Product : post exposure salt

Drying of liquid resin stamp

6. Finally, the plate is dried

Stamp mounting

Photopolymer stamp

Stamps are cut and placed on mounts
Products : adhesive foam, wooden or automatic mounts

RUBBER STAMP / PHOTOPOLYMER STAMP COMPARISON - ADVANTAGES AND DRAWBACKS OF EACH TECHNIQUE

advantages of photopolymer resin

  • Faster processing time (25 minutes)
  • A single machine is necessary , with low floor space requirements.
  • Low equipment write-off, thus lower cost price for stamps.

advantages of rubber

Conventional

  • Resistant, specially to alcohol based inks.
  • Increased durability
  • Better ink release (porous structure)
  • Choice of colors, « noble » material

Laser

  • Resistant, specially to alcohol based inks.
  • Increased durability
  • Better ink release (porous structure)
  • Choice of colors, « noble » material.
  • Fast processing time for a single stamp (3 min 30 sec)

drawbacks of photopolymer resin

  • Ink release is not as good as rubber
  • Lower durability.
  • Less resistant to alcohol based inks.

drawbacks of rubber

Conventional

  • Longer processing time
  • 2 machines are necessary (photopolyme plate maker + press) to mould matrix board and rubber).

Laser

  • Very long processing time for several stamps (2 hours 40 min for A 4 slab).
  • Important cost price, due to the laser write -off

ESTIMATIONS DES TEMPS DE FABRICATION ET PRIX DE REVIENT DES DEUX TECHNIQUES

    Photopolymer stamps   Conventional Rubber Stamps   Laser engraved Rubber stamps
Processing time for 1 A 4 size
(about 40 stamps)
  30 minutes
( + typesetting)
  1 heure 10 minutes
( + typesetting)
  2 heure 40 minutes
( + typesetting)
(with a 25 W laser)
Processing time for a single stamp   30 minutes
( + typesetting)
(Processing time is not proportional to surface)
  1 hour 10 min
(+ typesetting)
Processing time is not proportional to surface
  3 or 4 minutes
Processing time depends on the stamp surface
Processing time for further copies of a same stamp   30 min
All processing steps should be made
  3 minutes
(it is just necessary to cure rubber)
  3 to 4 minutes
(all processing steps should be made)
Cost for 1 stamp
(not including manpower, mount, equipment cost)
  0,26 Euros   0,45 Euros   0,27 Euros
Cost for several copies to the same stamp (not including manpower, mount, equipment cost)
  • first one
  • further copies
 



 

  • 0,26 Euros
  • 0,26 Euros
 



 

  • 0,45 Euros
  • 0,05 Euros
 



 

  • 0,27 Euros
  • 0,27 Euros