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Unused base inks that are not going to be used for printing production are considered to be hazardous materials. Their disposal is expensive, and strict environmental regulations should be followed for their disposal. As an alternative, this article describes how spectral data of unused base inks can be gathered and mixed to generate new colors to incorporate them back to print production for small‐volume jobs. In this study, 30 different Pantone colors were selected as target colors. The CIE L*a*b* spectral data of Pantone colors and unused base inks were gathered via a spectrophotometer. A commercial formulation software, based on multiflux theory and CIE L*a*b* color space, was used to formulate ink recipes that contained the base inks. To quantify the performance of ink recipes, they were mixed and printed using an offset printability tester. The CIELAB ΔE*ab metric, developed by CIE, was used to detect the visual differences between the target Pantone Color and printed colors.

Prerecycling of water-based flexographic ink and water-based thermal inkjet inks was explored. Model laboratory formulated water-based flexographic and commercial water-based thermal inkjet inks were used in experiments using solely wet or dry inks. The goal was to optimize ink detachment during repulping and at the same time assure its minimal ink redeposition. Ink’s behavior was examined under a wide pH range. An alkaline environment is desirable for complete ink detachment from the printed substrate, whereas the benefit of an acid environment is the agglomeration of the pigment in water-based ink. Deinking would be most efficient if executed in two steps: first, alkaline to detach most of the alkaline water-based ink and second, acidic to maintain detached ink coagulated. Acidic pH has the ability to agglomerate the pigment, once it is detached and present in deinking waters. However, such a recycling protocol is likely not achievable in current recycling plants.

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