Inkjet coating

Hladnik A. (2004) Use of specialty pigments in high-end inkjet coatings. 7 Dispers Sci Technol 25(4) 481. 

Divalent metal cations such as Ca2+ are used in some inkjet media, such as coated paper and glossy photorealistic media, to fix the water-soluble dye and make it waterfast by forming an insoluble salt. However, cationic organic compounds are currently the preferred choice for this function. 

Nanoparticles can be deposited onto a substrate by spin coating or inkjet printing a colloidal solution and can be sintered into a continuous conductive film during the subsequent annealing step. Coalescence of individual... 

PLEDs contain polymeric emissive materials that are almost exclusively processed by solution coating (spin coating or inkjetting). This has been discussed in Chapter 2. While most polymer work uses fluorescent emissive materials, there are a few examples of phosphorescent materials being incorporated into a polymer chain and being used as phosphorescent emitters. This part of the materials discussion will be covered in Chapter 4. 

Modern photographic-quality inkjet papers have a surface coating comprising either a thin polymer film or a fine porous layer. In either case the material is formed using a high-speed coating process. This process requires careful control to obtain the necessary uniformity together with... 

Porous inkjet papers are in general created from colloidal dispersions. The eventual random packing of the colloid particles in the coated and dried film creates an open porous structure. It is this open structure that gives photographic-quality inkjet paper its apparently dr/ quality as it comes off the printer. Both the pore structure and pore wettability control the liquid invasion of the coated layer and therefore the final destination of dyes. Dispersion and stability of the colloidal system may require dispersant chemistries specific to the particle and solution composition. In many colloidal systems particle-particle interactions lead to flocculation which in turn leads to an increase in viscosity of the system. The viscosity directly influences the coating process, through the inverse relation between viscosity and maximum coating speed. 

Applications used in waterborne coatings and adhesives, film modifications, high-performance coatings, and inkjet technology... 

Although spin coated OTFTs with PQT-12 semiconductors have high mobility and on/off ratio characteristics, the performance of those fabricated by inkjet patterning is more variable. This may be attributable to the tendency of PQT-12 solution to gel at room temperature, leading to nonuniformity in the jetted semiconductor channel layers. This deficiency of the PQT solution as an inkjet ink is expected to be a practical challenge in manufacture, and must therefore be addressed. By study of the solution behavior of PQTs, we have subsequently developed a nanoparticle dispersion of PQT-12, which effectively resolves this challenging problem (vide infra). 

Inks Coatings Manufacturer Pigments, Colorants Varnishes Conductive lnks Printed Electronic Technologies Inkjet Digital Printing Hardware Software Consulting Services... 

Surface treatments are often necessary for aesthetic and performance reasons. This can involve printing or lacquering, using both solvent and non-solvent based inks, which are applied to the surface using rollers, pads, silk screen, inkjet or lasers. Waterborne coatings are environmentally more desirable and silicone surfactants are claimed to give the best performance to improve substrate wetting (456). 

Using inkjet special substrate coatings is, most probably, the most widely used method to enhance inkjet printing quality for the SOHO (Small Office Home) markets. However, when dealing with commercial printing, e.g., wide format printers or non-porous substrates, top coats will neither guarantee the performance required by commercial customers, nor meet the cost goal required for most applications. 

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