The basic deinking process for old newspapers, the role of the deinking agent, the science and the condition for good deinking are reviewed based on the results in our laboratory first. Then, by using this typical deinking process, the deinkability of the pigment―based inkjet printings was examined. In commercial printings, the transition to on―demand printings is in progress, because the on―de...

BACKGROUND The development in the deinking process has made recycled fiber a major part of the raw material for pulp and paper industry. Enzymes have revolutionized the deinking process obtaining brightness levels surpassing conventional deinking processes. This study explores the deinking efficiencies of bacterial alkalophilic laccase (L) and xylanase (X) enzymes along with physical deinking m...

Hewlett-Packard (HP) is actively engaged in external and internal research to ensure that deinkability of the current recycled paper streams is maintained as the percentage of digital prints in deinking mill furnish increases. As part of this effort, HP is working to understand how ink and paper interactions affect the flotation deinking process. Results continue to show that paper type and des...

Hewlett-Packard (HP) is actively engaged in external and internal research to ensure that deinkability of the current recycled paper streams is maintained as the percentage of digital prints in deinking mill furnish increases. As part of this effort HP is working to understand how ink and paper interactions for both inkjet and liquid electrophotography affect the flotation deinking process. Res...

Deinked pulp fibers produced by three kinds of deinking processes, alkaline deinking, neutral deinking, and enzymatic deinking, were studied by Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectrometer (FTIR), X-ray Diffraction (XRD), and CrossPolarization Magic Angle Spinning Carbon-13 Nuclear Magnetic Resonance (CP/MAS 13 C-NMR). There were remarkable differences in both mac...

One of the most difficult recycling tasks is deinking of digitally printed paper with water based inkjet inks. The deinking of such paper is very important for the improvement of the digital printing industry. Generally, the manufacturers’ preferred method is INGEDE Method 11p, which defines the universal deinking process. Based on this method, two different deinking procedures were assessed. T...

Flotation deinking of old newsprint (ONP) using polydiallyldimethylammonium chloride (polyDADMAC) as the only deinking agent was studied. The results demonstrate that polyDADMAC can neutralize dissolved anionics to form small particles. These small particles, together with ink, filler, and fines, strongly adsorbed onto air bubble surfaces and functioned as particle foaming agents. Therefore, no...

Twenty thermophilic/thermotolerant fungal strains were isolated from compositing soils and screened for production of different enzymes (Endoglucanases, β-glucosidase, Fpase and xylanases) to assess their deinking efficiency. Three isolates, Aspergillus sp. AMA, Aspergillus terreus AN1, and Myceliophthora fergusii T4I, identified on the basis of morphological and sequencing of amplified ITS1-5....

The efficiency of ink separation in the process of waste paper recycling depends among other things on the ink properties, kind of the substrate, the printing techniques and the printing conditions. Chemical deinking flotation does not efficiently remove water based flexographic inks, UV ink and varnish, ElectroInk and some toners from digital printed paper. The use of enzymes could be an alter...

Enzymatic versus chemical deinking is examined for MOW and photocopy prints. Several enzymatic preparations and two fibre/ink particle separation methods are tested. Deinking was monitored by image analysis and standard pulp and paper characterisation procedures. The effectiveness of the fibre/ink particle separation method depends on the ink particle's size: for smaller particles a washing ste...