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In the first of three articles reviewing Commercial Printing Ink Pigmentation the classification and various printing systems are considered.

The properties and constituents of PTF inks are outlined. Surface resistivity in relation to PTF inks is defined. Applications of PTF inks are discussed with emphasis on potential design and cost benefits for SMT applications, including crossovers, polymer multilayer, printing through holes, printed resistors, carbon key pads, moulded and three‐dimensional circuits.

The main developments in the metallic inks market are currently focused on the need to reduce volatile organic compounds (VOCs) in the ink formulation, responding to existing and future legislation. Two of the most recent successes in the move away from solvents are water‐based metallic inks and UV (ultra violet) curing metallic inks. Both products, because of their metallic content, have inherent problems associated with their successful manufacture, which must be overcome if the products are to be accepted as viable replacements for traditional solvent‐based formulations.

The ink maker and printer are vitally concerned with the behaviour to be expected from a pigment in terms of its contribution to printing properties (such as rheology, bleeding, damping water incompatibility), print appearance (colour, lustre), and useful service life (fading, resistance to chemical attack). Although practical printing tests can properly demonstrate the ultimate utility of a pigment for an intended use, sufficient preliminary data can normally be assembled to suggest candidate pigments suitable for evaluation.

Recent years have seen a rapid development of ink‐jet printing technology. This paper reviews the state‐of‐the‐art in ink‐jet printing technology and gives an overview of ink‐jet printing into the immediate future. The focus is placed on various applications of jet printing technology. The potential of applying jetting technology in the conventionally surface coating dominated applications will also be explored.

The initial objective of NAPIM's misting project at Lehigh University is to develop a viable standard test method for evaluating the misting tendencies of printing inks. An ensuing objective will be to identify the ink characteristics responsible for misting. Development of such information is expected to uncover approaches for minimizing misting problems.

The purpose of this paper is to prepare and characterise various ink formulations for inkjet printing on nylon 66 carpet.

Various ink formulations were prepared using CI Acid Red 57, synthetic thickeners (BYK425 and BYK420), ethylene glycol, diethylene glycol, isopropanol with auxiliaries. The inks were characterised for their rheological, wetting and storage stability properties. The inks were jetted using a Printos P16 drop‐on‐demand jet print‐head onto nylon 66 carpet materials. The printed images were characterised using an ImageXpert system.

It is found that the inks containing the synthetic thickeners at the optimum ratio give good printing and image properties, such as optical density, drop size, and depth of penetration into the substrate at pH 4‐5. The optimised ink formulation is found to have good storage stability.

The study focuses on ink formulations based on CI Acid Red 57. Ink formulations based on other colorants could also be studied in order to assess the applicability of the ink formulation system found for other colorants.

The ink formulations developed could find use in industrial scale printing.

Low cost ink formulations for printing of nylon carpets are novel.

Ink mist consists of airborne droplets of ink ejected from the nip of press distribution systems and other rotating rolls as a result of the ink film splitting process. To help the printing ink industry deal with the problem, the National Association of Printing Ink Manufacturers, through the NAPIM Technical Institute, inaugurated a project on misting at Lehigh University. The objective of this project was to develop a reliable laboratory test to rate the misting tendencies of printing inks.

Related even more closely to the coatings industry's technology are printing inks. Like coatings, inks comprise a combination of vehicles, pigments, and small percentage additives Inks do not serve a protective function in the same way that coatings do but they must, on the other hand, adhere to the substrate and they must certainly frequently be decorative. Conversely, practically all inks are applied in a “factory”, analogous to factory‐applied or industrial coatings. The analogy goes even further in that the application is done by highly automated equipment at rapid speeds, although it must be pointed out that inks are applied much more rapidly than most coatings.

Ballpoint pen ink analysis is important for forensic scientist which can collect valuable information on questioned document. Inks widely used now constitute many substances to improve needed ink characteristics, including the coloring material (dyes or pigments), inks, solvents and resins. The complex components of the inks confront forensic ink chemists with a big challenge to carry out this analysis. However, because of the great importance of determining whether two pieces of written text originated from the same ink, therefore, comparison of different writing inks on a document to forensic scientist, many techniques have been tentatively employed in the ink analysis. In this study, Raman microscope was employed successfully in the analysis of inks. The paper aims to discuss these issues.

Damped or wet samples cannot be analyzed by IR if dehydration is not carried out FTIR observation, because of the extremely strong absorbance of water. Raman spectroscopy can cover the shortage of FTIR spectroscopy because water has weak absorbance in Raman spectroscopy. Raman shifts can give extra peak information because it usually has different positions with FTIR spectroscopy. A Renishaw inVia confocal Raman microscope system with two lasers emitting at 532/633 nm, charge-coupled device detector was employed collecting the Raman spectrum. Laser was chosen for emission in 1-100 percent power depending on the proper energy to get signal strong enough and protect the samples from burning. At least triple-tests were performed for each sample.

The result indicated that Raman spectroscopy could easily remove the interference caused by the paper which could hardly be removed with infrared spectroscopy. No sample preparation was required and only 30 s was needed for each sample in the optimized method. The method proved to be fast, accurate, non-destructive and could be easily applied to the real cases. The primary survey on inks from different market indicated five kinds of inks could be identified. The indicative peaks of each kind of ink (693, 1,150-1,210, 1,280-1,300, 1,360-1,400 and 1,531 cm−1) were summarized. The distributions of the inks in markets were also illustrated. Ink using alkyd resin as connecting materials or copper phthalocyanine as pigment decreased significantly. The data in this study would be helpful for the forensic scientists to identify these inks and examine the questioned document.

No previous studies on the analysis of inks in China market were found to the authors’ best, so the forensic scientists have no idea about the method using Raman for discrimination which proved to be effective, accurate and fast, the indicative peaks of each inks, the distributions in the markets, and therefore, the possibility to encounter specific ink in cases The data in this study would be helpful for the forensic scientists to identify these inks and examine the questioned document.