Silkscreen Legends
While elsewhere in the world, silkscreen legends are still applied using traditional screenprinting, for the last seven years we have been using an Industrial Ink Jet printer for white silkscreen legends that adhere to minimums on line width and text height. For those legends that are smaller than what the Ink Jet printer can resolve or for other legend colours, we use the same photo-imageable process as that used for soldermask, but at a cost of both time and money. PI legends cost more because we need to plot artworks, mix and apply a special batch of ink and hand image & develop. They cost time because the whole process for a single panel is 4 hours.
So when working on a legend, make sure of the following for legible Ink Jet printing:
- Legend text height: minimum 1.5mm
- Legend text width: minimum 0.2mm
Legends with text height of 1.0mm and width of 0.15mm are printable but may be thin, a bit washed out or hard to read. Quite often a ratio of height to width is preset in your design package – it is worth checking and manually overriding if necessary.
If a coloured or a tight legend is required, then PI legend is the way to go. Minimum surcharge for this is $60.00 + GST which covers up to 5 panels and adds a day to the quoted leadtime. PI legends are NOT available on sprint leadtimes, only on 5+WD services and actually make a 5WD service a 6WD service. Minimums for PI Legends:
- Legend text height: minimum 0.8mm
- Legend text width: minimum 0.15mm
