I thought it was K for "key", not "kohl"
Though I'm not sure on this, tbh.
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Tab Hunter Make this useless process end and so, begin again, Wed 12 Dec 2012, 10:59,
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K for key line...?
Used for aligning the CMY colour plates, I thought. Doesn't have to be black...
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FridgeBadger, Wed 12 Dec 2012, 11:40,
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