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The present work aims to deal with ultrasound-assisted organic pigment (phthalocyanine blue and green) dispersion and its comparison with the conventional approach.

Ultrasound is expected to give beneficial results based on the strong shear forces generated by cavitational effects. The dispersion quality for preparation using an ultrasound-based method has been compared with dispersion obtained using high-speed dispersion mill. Effects of different operating parameters such as probe diameter and use of surfactants on the physical properties of dispersion and the colour strength have been investigated. Calculations for the energy requirement for two approaches have also been presented.

The use of sodium dodecyl sulphate and Tween 80 surfactants shows better performance in terms of the colour properties of dispersion prepared in water and organic solvent, respectively. Ultrasound gives better dispersion quality as compared to the conventional approach.

The present work presents a new approach of ultrasound-assisted dispersion of phthalocyanine blue and green pigments. Understanding into the effect of surfactants and type of solvent also presents new important design-related information.

This research deals with a new kind of nanopigment, obtained from the combination of organic dyes and layered nanoclays, that the authors call nanoclay‐colorant pigment (NCP). Whilst they have already been employed in inks and coatings, to date these nanopigments have not been used as pigments for polymers. The existing lack of knowledge surrounding them must be redressed in order to bridge the gap between current academic studies and commercial exploitation. Therefore, the main purpose of this paper is to examine the hitherto unknown aspects of the NCP, which relate specifically to their applicability as a new type of colorant for polymers.

A blue NCP has been prepared at the laboratory according to the patented method of synthesis (patent WO0104216), using methylene blue and montmorillonite nanoclay. It has then been applied to a thermoplastic polymer (linear low‐density polyethylene – LLDPE) to obtain a coloured sample. Furthermore, samples with the same polymer but using conventional blue colorants have been prepared under the same processing conditions. The mechanical, thermal and colorimetric properties of these materials have been compared.

The thermal stability of the sample coloured with NCP is reduced to some extent, while the mechanical strength is slightly increased. Moreover, this sample has better colour performance than the conventionally pigmented samples.

In this paper, a blue NCP has been synthesised and successfully employed with polyethylene and the obtained sample shows better colour performance than polyethylene with conventional pigments.

This article is an attempt to discuss pigments used in the paint, printing ink, plastics and rubber industries in a general way, prior to their more detailed description by specialists in the subsequent articles in this issue of the journal.

The paper introduces a new method for single step synthesis of copper phthalocyanine green pigment using microwave irradiation to activate C−H bonds on the aromatic rings that are possible by creation of chlorine radicals. The aims of this study are to investigate the possibility of high-efficiency product reaction, removing acidic wastewater, time optimization, and maximizing number of chlorine on aromatic rings.

The paper presents a new synthesis technique, which does not have the problems of the conventional methods. Microwave irradiation is used as a chemical reaction initiator by creation of chlorine radicals in saturated aqueous solution of sodium chloride and C−H bond activation on aromatic rings. The approach yields to a high quality of product, uniform particle size distribution, high efficiency and an environmental friendly procedure.

The paper introduces the use of suitable materials and water solvents in chemical reactions under microwave radiation at low temperatures. This shows that the microwave irradiation activates C−H bonds on aromatic rings and creates chlorine radicals at the same time, which results in relatively fast reaction of synthesis copper phthalocyanine green.

The ammonium molybdate catalyst, which is used in this method, should be weighed carefully. The effects of transition metals on chemical reactions in the presence of microwave irradiation can also be chlorinated other unsaturated bonds.

The method develops a simple and practical solution to improve the synthesis of phthalocyanine green pigment.

The synthesis method of copper phthalocyanine green pigment is novel. CuPhcCl₁₆ has numerous applications in industrial.

The purpose of this paper is to identify different automotive coatings using Confocal Raman microscope which could hardly be differentiated with Fourier transform infrared microscope (FTIR).

Raman spectroscopy was used to provide extra vibration information to infrared spectroscopy. Paints preparation was not necessary, and only 30 s was needed for each sample in an optimised method. Paints were first analysed by FTIR and then compared with Raman microscope.

Raman microscope was used to address the lack of ability of FTIR in discriminating four groups of paints in same colours. This study indicated that Raman microscopy is especially effective in sensing pigments and could successfully identify all pigments in the paints.

The two instruments in combination produce accurate results than when used individually, especially in complex and multi-layered paints analysis.

The method proved to be fast, accurate and non-destructive, and it could be easily applied to real cases.

With this method, scientists could discriminate some coating types which were hard to be discriminated by other techniques.

A selection of organic and inorganic pigments has been evaluated in an epoxy powder coating system and the results are tabulated and discussed.

Today's narrowing environment requires new ways of looking at the organic pigments industry. In particular a reconstruction of organic pigments is needed in relation to “TOSCA” the Toxic Substances Control Act (USA), which has swiftly become the issue of the hour.

The purpose of this paper is to provide a novel method for encapsulation of phthalocyanine blue pigment for inkjet printing inks.

Phthalocyanine blue pigment was encapsulated by emulsion polymerisation of styrene and a polymerisable dispersant, allyloxy nonyl‐phenoxy propanol polyoxyethylene ether ammonium sulphonate (ANPS). The encapsulated phthalocyanine blue pigment was further formulated into dispersion. The encapsulated phthalocyanine blue pigment was characterised with transmission electron microscopy (TEM), thermogravimetric analyses (TGA), X‐ray diffraction (XRD), Zeta potential and contact angle measurements. The encapsulated phthalocyanine blue pigment dispersion was evaluated in terms of rheological behaviour, particle size distribution and stability.

TEM and TGA proved that polymer encapsulation layer was formed onto phthalocyanine blue pigment surface. XRD indicated that the crystal structure of phthalocyanine blue pigment was not changed during the encapsulation process. The wettability of phthalocyanine blue pigment was improved after polymer encapsulation. The dispersion formulated with encapsulated phthalocyanine blue pigment had a narrow particle size distribution, excellent stability to temperature and centrifugal forces. Its rheological behaviour was close to Newtonian fluid.

The methods provided a novel and practical solution for preparing the encapsulated phthalocyanine blue pigment dispersion for formulation of inkjet printing ink.

The paper demonstrates how emulsion polymerisation technique is employed to encapsulate phthalocyanine blue pigment using a polymerisable dispersant, ANPS, which imparts to dispersion a small particle size, narrow particle size distribution and high stability.

Printing inks fall into two more or less distinct rheological classes—highly viscous inks formulated for letterpress, offset, and typographical printing versus relatively fluid inks formulated for flexographic and rotogravure printing.

In the printing ink industry, the trend increasingly points towards the application of special varnish systems and pigments for packaging and decorative inks. As a consequence, there is an increasing demand for equipment capable of coping with this difficult dispersion process. Buhler has accepted this challenge, launching a bead mill provided with a conical gap agitator and a dynamic separation gap relief system.