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Serendipity has been a major player in most dye discoveries, and phthalocyanines are no exception. The true account of their discovery in 1928 is given using information provided by one of the individuals involved (Ron Greig). One of the inventors, Drescher, after making a key observation as to the nature of the insoluble blue impurity formed in the routine manufacture of phthalimide from phthalic anhydride, was killed weeks later when, on his beloved Sunbeam motorcycle, he had a head-on collision with a steamroller on his way to work. The unique properties of phthalocyanine dyes and pigments make them the colorant of choice for most blue and green colours. Thus most blue and green cars, including sports cars, are coloured by phthalocyanine pigments. In addition to these traditional uses, phthalocyanines are also finding extensive use in modern hi-tech areas. They are used for their colour as, for example, cyan dyes in ink jet printing, and in colourless applications such as infrared absorbers in security. The discovery, traditional and hitech applications of phthalocyanines are described in detail in this paper.

Structural composition of 11 trace elements with Z greater than 13 (Al, P, Si, K, Ca, Mn, Fe, Cu, Zn, Mo, I) was analyzed for the two main groups of human gallstones according to their cholesterol and pigment types by PIXE (Proton Induced X - ray Emission). In both types of stones, the shell and the center were analyzed separately. The gallstones were obtained from 12 patients in wide age group from 22 to 78 years of age during surgical operation. The results show relatively higher values of heavy elements for ages greater than 40. The values of phosphorous in cholesterol type stones are significantly higher than in those of pigment stones. The concentration of calcium in the center of stones is large in comparison with that in the shells. In this paper, a correlation between stone structure and trace elemental concentration has been presented. Comparison of the two essential types of stones (cholesterol and pigment) shows that the center of the pigment stones is very similar to that of the cholesterol type.

Pigments used in lacquerware pieces excavated from the Edo-period stratum at the southern part of Kawauchi campus of Tohoku University are analyzed using an in-air submilli-PIXE camera. That area is located at the former secondary citadel area of Sendai's Aoba Castle. The lacquerware pieces were analyzed as elemental images without sample degradation and without sample preparation. Pigments used in the red lacquer resin were cinnabar and Bengala. This analytical method, which uses images, was effective for discrimination of contaminant elements through comparison with the decoration. Results show that PIXE analysis using the in-air submilli-PIXE camera is an effective tool for use in archeological studies.

Natural melanin is a sustainable and environmentally friendly pigment. The structural properties of melanin are of great significance for its functional applications. In this study, the preliminary composition and structure of melanin extracted from the induced cultures of Lasiodiplodia theobromae were qualitatively characterized by ultraviolet-visible (UV) spectrophotometer, elemental analysis (EA), Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR) and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). The results showed that the secreted melanin contained many functional groups such as hydroxy groups, alkanes and aromatic rings, which belonged to benzoquinone structure and aliphatic structure. The melanin secreted by Lasiodiplodia theobromae can be identified as a type of allomelanin. This research work is expected to provide a reference for the application of melanin in various fields in the future.

The antibacterial properties of the components in building latex paint, such as latex, auxiliary materials, pigments and so on, were studied by testing the inhibitory ring and the minimal inhibitory concentration (MIC). The effect from each component on the antibacterial properties of paint film was further investigated. In this study, the antibacterial activity of 5 kinds of latex, 17 kinds of auxiliary materials and 8 kinds of pigments against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were tested. Experimental results showed that the antibacterial ring was observed in only one kind of silicone acrylic latex. Most of auxiliary materials in this study showed antibacterial effect on the two bacterial cells. None of pigment and fillers showed antibacterial effect. However, the paint films made up of the above components had no bacterial effect against E. coli and S. aureus after being dried for 7 days. The latex and auxiliary materials contained some toxic monomer and polar groups, leading to the antibacterial effect. But the antibacterial effect disappeared after crosslinking reaction during the process the formation of paint films. As a result, all these components showed little contribution to the antibacterial effect of paint films. The most effective way to improve the antibacterial effect of paint films was to add Ag-series of inorganic antibacterial materials or some organic antibacterial materials.