The process of quality control in flexo is a very important to ensure that the expected results are maintained and to obtain a high quality printing plate. The process of quality control can be divided into a set of specific points that can be reviewed and measured in the various stages of printing plate production.

FLEXO QUALITY CONTROL ELEMENTS

  1. Technical Artwork
  2. Ripped Digital File
  3. Imaging
  4. Processing / Exposing / Finishing

1. TECHNICAL ARTWORK FILE

The artwork file must conform to the technical specifications in terms of surface or reverse printing. It must also be identical in terms of processing operations that conform to the printing standards.

𝔰𝔯𝔠 AGFA
An artwork file

2. RIPPED DIGITAL FILE

After reproducing the technical file, you cannot modify it, but you can review it and return it to the technical department for reproduction and modification to obtain the desired result.

Important points to note:

  • Right reading / wrong reading “surface or reverse printing“
  • Linescreen, angle, resolution, curve and dot shape “circular dot or hybrid screen“
  • File Dimensions
  • Distortion Value
  • Registration mark
𝔰𝔯𝔠 Wapcaplet
Screens and Halftones
𝔰𝔯𝔠 Anyflexo
Registration Mark
𝔰𝔯𝔠 Onyx
Resolution, Dimension, Colours and Surface and Reverse Printing

3. IMAGING

The printing film industry depends on the quality of the polymer and on the mask ablation of the digital plate , which depends on many important elements that must be taken into account.

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Mask Ablation

Measurements will be obtained during this process using a transmission densitometer.

𝔰𝔯𝔠 Techkon
Techkon Densitometer

– the operator should Measure the Density of the mask from 3.5 to 4.3 before ablation

– the operator should make a Focus test

Basic setting and calibration of the laser Before testing the plate making times, the laser must be set for the respective plate. The basic laser parameter settings, i.e. the focus, the energy or power of the laser, and/or the rotation speed of the laser drum must be set. Focus While taking into account the plate thickness, the laser beam must be focused on the surface of the plate in such a way that a sharp ablation of the finest elements can be achieved. The procedure to be adopted is defined in the specified test routines provided by the laser manufacturer.  Calculating the laser energy  Once the focus has been adjusted correctly, the next step is to determine the amount of laser energy that is  required to remove the black layer without creating a grey film and linear to the digital data.

4. Processing / Exposing / Finishing

𝔰𝔯𝔠 Anyflexo

After the plate is processed, it is necessary to carry out measurements to ensure specification compliance. These results are dependent on the condition of the platemaking equipment and adequate monitoring of the processing conditions found during optimisation. You should consider the following control points:

  • Caliber
  • Relief
  • Dot formation
  • Cleaning
𝔰𝔯𝔠 Sibress
FC3D+ Flexoplate Camera Mesure System

With FC3D+ you can measure the Caliber, Relief and check Dot formation and Dot shape easily.

Quality control in the prepress equipment room is one of the most important stages for obtaining a high quality flexo plate that conforms to the specifications.

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