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Phthalocyanine compounds have their importance due to the massive utilization in various fields. Phthalocyanine blues and greens are used as pigments because of their outstanding stability to light, heat, acids and alkalis, and of course, their insolubility in water and organic solvents. They are used in printing inks, paints and plastics. Phthalocyanines are also used as catalyst in suffer oxidations in the petroleum industry and find use in lasers, medicines, photography, as photo‐ and semiconductors, in xerography and as indicators.

Some organo‐metallic pigments namely copper phthalocyanine, metal and metal free biphthalocyanines, halogenated copper phthalocyanine and two inorganic pigments (red and yellow iron oxides) were incorporated into styrene butadiene rubber mixes (SBR). The rheometric characteristics and mechanical properties of the compounded rubber were investigated. The antioxidant efficiency of the above mentioned pigments were evaluated. Beside their good colouring effect the synthesized copper and nickel biphthalocyanines and the commercial red iron oxide have a significant effect on the properties of rubber vulcanizates after ageing. In addition, nickel biphthalocyanine and red iron oxide can be successfully used as ultraviolet stabilizers for rubber vulcanizates.

This paper aims to propose a simple, effective and environmentally benign method for the synthesis of commercially important pigment copper phthalocyanine (PC) blue has been developed using deep eutectic solvent (DES).

DES prepared from choline chloride and urea is used as a reaction medium, as well as a source of ammonia. The design of the experiment and factorial design study has proved that the milder reaction conditions with high yields and reusability of DES are the key features of the present study.

The synthesized pigment is obtained at milder reaction conditions with excellent yield, which can be seen from the design of experiments done for the optimization of results.

The synthesized pigment was used as a colorant in epoxy-based paint and in screen ink, which gave satisfactory results with respect to color values and stability.

The screen ink prepared was formulated considering environmental aspects to avoid the use of solvents. Biodegradable components were added to the colorant to make the ink environment friendly.

Reactions occur at moderate temperatures without affecting the time factor, thus, it saves energy. A simple, effective and environmentally benign method for the synthesis of commercially important copper PC has been developed using DES. After the first batch, DES synthesized can be reused as a reaction medium where only a stoichiometric amount of urea is to be added. Simple work up, high yield and purity are achieved.

The purpose of this paper is to enhance the limited fluorescence of mica titania (MT) effect pigments by coating them with peripherally substituted zinc phthalocyanines (ZnPc).

The effects of deposition medium, temperature, time, initial organic pigment/MT ratio on deposition behaviour and efficiencies were investigated separately for ZnPc, nitro (TNZnPc) and amino (TAZnPc) substituted ZnPc’s.

TNZnPc could be deposited in the form of well-defined crystals on MT with per cent 64 ± 5 efficiency in chloroform at 50°C within 5 h and the amount deposited was linearly dependent on the initial TNZnPc concentration. TNZnPc fluorescence emissions, which appear mainly at 460 and 685 nm in pure pigments, could be observed in combination with MT (MT-TNZnPc) as well. A spectral analysis on the non-overlapping region of the spectrum with two different excitations (385 and 630 nm) revealed that, respectively, up to threefold to sixfold increase is possible to attain, depending on the excitation wavelengths.

Efficiency of deposition could not be taken above per cent 11 ± 4 with TAZnPc. Although ZnPc could be deposited with per cent 57 ± 3 efficiency, the pigment was not effective in imposing its fluorescence characteristics over MT.

Combining inorganic effect pigments with organic dye molecules is an idea that has been elaborated mainly for producing different colour effects and stabilization of dye molecules against agglomeration. Here, for the first time, it is used to enhance the fluorescence of the effect pigments.

The purpose of this paper is to investigate the effect of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) on improvement of physical and electrical properties of vanadyl phthalocyanine derivative. The correlation between the physical characteristics of the active layers, comprising vanadyl 2,9,16, 23-tetraphenoxy-29H,31H-phthalocyanine (VOPcPhO) and PCBM, and the electrical properties of metal/organic/metal devices have been studied. The use of soluble vanadyl phthalocyanine derivative makes it very attractive for a variety of applications due to its tunable properties and high solubility.

The sandwich type structures Al/VOPcPhO/Al and Al/VOPcPhO:PCBM/Al were fabricated by spin casting the active organic layers between the top and bottom (aluminum) electrodes. The stand-alone (VOPcPhO) and composite (VOPcPhO:PCBM) thin films were characterized by X-ray diffraction, atomic force microscopy, UV/Vis and Raman spectroscopy. The electronic properties of the metal/organic/metal devices were studied using current-voltage (I-V) characteristics in dark at room temperature.

The values of barrier height for Al/VOPcPhO/Al and Al/VOPcPhO:PCBM/Al devices were obtained from the forward bias I-V curves and were found to be 0.7 eV and 0.62 eV, respectively. The present study indicates that the device employing VOPcPhO:PCBM composite film as the active layer, with better structural and morphological characteristics, results in reduced barrier height at the metal-organic film interface as compared to the one fabricated with the stand-alone film.

It is shown that doping VOPcPhO with PCBM improves the crystallinity, morphology and junction properties.

The spin coating technique provides a simple, less expensive and effective approach for preparing thin films. The soluble VOPcPhO is conveniently dissolved in a number of organic solvents.

The physical properties of the VOPcPhO:PCBM composite thin film and the electrical properties of the composite thin-film-based metal/organic/metal devices have not been reported in the literature, as far as our knowledge is concerned.

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.

Screenprinting has formed an integral part of the manufacturing process for PCBs since the first boards were produced. This paper describes the types of product used, the areas of application, and suggests methods for obtaining the best results by exploring printing parameters and indicating methods of optimising them to minimise faults.

Highly coloured, thermally stable metal free, copper, cobalt and nickel of the hexadecachloro‐ and hexadecabromo‐phthalocyanine were synthesized by the urea fusion technique in the dry method. The structure of these compounds was confirmed via spectrophotometric measurements such as ultraviolet‐visible, nuclear magnetic resonance and infrared spectra. Evaluates the pigmentary properties of these compounds according to standard international methods. From the results reveals that these compounds have outstanding properties which allow them to be excellent pigments for various applications.

Examines whether there are any environmental or health implications associated with the increased use of colour in newspapers, if the newspapers are reused or recycled. New heavy metal analyses of UK daily newspapers from 1992, 1996 and 1998 are reported. Lead, mercury and cadmium were found to be below their measurement detection limits (4ppm, 5ppm and 1ppm respectively) in nearly all samples. Barium and total chromium levels were highest in supplements printed on “glossy” paper. Copper was present at levels around 20‐30ppm in the standard newsprint sections and at levels of 80ppm or more in the supplements. Copper concentrations increased by 33‐40 per cent between 1992 and 1998 which correlated well with the increased colour content. A scientific appraisal and review showed that the heavy metal contents of newspapers are highly unlikely to pose any environmental risk or to have any health implications.

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.