Troubleshooting I Structures in Matt Coatings
The challenges of structures in matt coating
The requirements placed on waterbased matt coatings are obvious. On the one hand, they must produce the requested matt level. On the other hand, they have to enable a structure-free surface. However, especially matt coatings may face running problems. This means: The matter the coating, the higher the danger of texture in the matt coating. The reason: Matt coatings contain matt pigments. Depending on the matt level, these pigments distinguish themselves in their constitution. Generally, dull matt coatings contain pigments which are coarser than those contained in silky matt coatings. Transferring the matt coating, the pigments are distributed by chance. If they come to a position where they are placed on top of each other, the result can be a visual uneasy surface with an inhomogeneous matt effect. In order to prevent texture in the matt coating, it is important to adjust anilox roller, coating plate and coating to each other.
Solving structures in matt coating
Step by Step
1. Stir your coating
Usually, matt pigments settle at the bottom of the coating container. In order to ensure a consistent distribution of the pigments, stir the coating well. We recommend that you repeat this procedure several times during varnishing.
2. Check coating application and anilox roller
The higher the coating application amount, the more matt pigments are transferred. Thus, the risk is increasing that pigments are placed on each other. Reduce your coating application. Choose an anilox roller with a cell volume of 9 - 11 cm³/m². Both hexagonal and tri-helical engravings can be recommended.
3. Choose the right coating plate
For the full area coating without gaps use a rubber blanket or a coating plate with a rubber blanket surface. By means of a soft surface, matt pigments can be transferred in a better way compared to a surface which is even or too hard. For the spot coating we recommend the use of a photopolymer plate.
Your checklist
Influence factor: Coating
Measure: Stir well
Influence factor: Coating application
Measure: Reduce coating amount
Influence factor: Coating plate
Measure: Choose an alternative
Still have open questions? Contact us and we will support you with the application.
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