PREPRESS PRESS POSTPRESS
Saphira Violet Plate Technical Bulletin – Plate Blinding
Plate blinding is defined as condition when blinded image. If the highlight area is
the image is ready to take ink but will not. over exposed or over developed, the
The precursor can be very slow roll up image will measure less than
requiring extra make ready to achieve proper required to print properly. A quick
ink density. exposure test and review of
processing parameters will resolve
Processor Related Contributing Factors to any suspicions.
Roll Up Blinding:
Press Related Contributing Factors to
If blinding occurs, the application of Finisher Blinding:
Concentrate directly to a clean plate can
'renew' the image area. If this application The Saphira Violet Plate is a very durable
works reviewing the processor maintenance plate. Wear and chemical characteristics
schedule is required. exceed most customers’ requirements.
• Maintenance of any processor is key Basic items to start reviewing press related
to its optimum performance. Length blinding are press set up and chemicals. The
of time between cleaning or square short list of leading factors is:
meter of plates used determines the
maintenance cycle. If the processor • Harsh chemicals can affect the plate
is outside of the recommended coating. Most notable - a scratch
range, cleaning is the first step in remover that is allowed to dry on the
moving forward. image area can stop the image from
taking ink.
• Check the wash water filters (the
intake screen and inline filter). If • Improper roller or impression
these filters are not cleaned, gelatin (plate/blanket/impression cylinder)
can remain on the plate surface. This settings lead poor printing conditions.
gelatin haze will not allow the finisher
to work properly. In extreme cases,
the rinse (the first finisher section) will For further troubleshooting of blinding, please
become over loaded with plate contact your Heidelberg Regional Plate
coating. Specialist.
• Finisher prepares the image area to
accept ink. Over extending the
finisher will cause blinding. Cleaning Heidelberg Contact Information:
will resolve any blinding directly
related to this section. Heidelberg Consumables
888 472 9655
• The Saphira Violet Plate is positive
working. The non-image area is Heidelberg Service
exposed to create a press ready 800 437 7388
plate. Improper exposure or
development can lead to a perceived
Consumables
SVPTechBulletin_Blinding_D3_6.29.04.doc