Offset ink

Offset ink is a specific type of ink used in conjunction with offset printing presses such as those used to produce letterpress or lithography prints. Such ink must be specially formulated to resist other chemicals it will come in contact with on the printing press. It is crucial that offset ink resist water-in-ink emulsification (e.g. repel rather than absorb water). It should also withstand degradation by the fountain solution which covers the non-printing areas of the engraved plate.

Offset ink need also be very rich in pigment so that it's full color vibrancy is perceptible even in minute quantity.

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