Conqueror for Indigo is production treated with an active chemical to maximize the ink adhesion.ArjoWiggins has found that another chemical, the candidate compound, would improve the propertiesof the paper. ArjoWiggins therefore wish to replace the current compound. To strengthenthe patent requirements for ink adhesion needs to be determined. A theory is developed to whychemicals with certain properties maximize the ink adhesion. Experiments are performed but theresults are inaccurate. The reason for ink adhesion is still unknown.Paper treated with the candidate compound is produced in a production trial and the paper evaluated.The paper shows decreased ink adhesion compared to paper treated with current compoundbut gives higher whiteness, longer shelf life and the formulation is preferred by the milldue to health and safety reasons.

The objective of this study was to evaluate and compare the print performance of some of the new most promising, cost effective absorbent pigments specialised for inkjet coatings on the market in a continuous drive to find an alternative to silica. The target was a lower production cost for ArjoWiggins inkjet products, OMD 01 and OMD 02. Five absorbent pigments are being evaluated through measuring the qualities of the coating mix itself, visual evaluations of print performance and physical testing of the coated paper. Pigments 1,2 and 3, which all are said to be tailored for inkjet coatings, did not reach the print performance needed for an OMD 01 and OMD 02 equal, due to severe bleed and feathering identified especially on the Epson 950 printer. They are therefore currently not seen as viable formulations. A blend of 50% pigment 5 and 50% silica had excellent print performance as OMD 01 and OMD 02 equivalents and is therefore recommended as a potential alternative to 100% silica. It is of the company’s interest to find a more cost effective solution to their inkjet coatings, and a 50/50 blend of Pigment 5 will save the company more than 35 000 euro per year.