Phthalocyanine solid solution nanoparticles consisting of brominated chlorinated zinc phthalocyanine (Zn-Pc) and copper phthalocyanine (Cu-Pc) were fabricated using the forced thin film reactor (FTFR). In this method, the phthalocyanine nanoparticles were crystallized by mixing water with phthalocyanine solution, which was made from dissolving Cu-Pc and Zn-Pc (Cu : Zn = 3.8 : 6.2, 5.8 : 4.2, and 7.6 : 2.4 molar ratio) in fuming sulfuric acid. The analysis results of the fabricated phthalocyanine nanoparticles by X-ray diffraction (XRD), infrared spectroscopy (IR), inductively coupled plasma spectroscopy (ICP) and scanning transmission electron microscopy-energy dispersive spectroscopy (STEM-EDS) showed phthalocyanine solid solution nanoparticles with a uniform distribution of Cu and Zn. Moreover the diameters of the phthalocyanine particles were 10 ~ 30 nm. From the result of the dispersion analysis of the phthalocyanine nanoparticles using utra-violet and visible spectrophotometry (UV-Vis) in a visible region, it was confirmed that the transmission regions of the phthalocyanine nanoparticles were controllable by the molar ratio of Cu and Zn. From the result of the thermal characteristic by thermogravimetry-differential thermal analysis (TG-DTA), it was confirmed that the decomposition temperatures of the phthalocyanine nanoparticles were higher than those of the raw materials. It was found possible to fabricate phthalocyanine solid solution nanoparticles with novel characteristics using the FTFR.
Wetting mode and shape changes of ultrasmall water droplets (80−100 nL) were observed during evaporation on superhydrophobic surfaces with different random roughness sizes. Observation of droplets from a top view revealed that the nanometer-coating transition was from Cassie's mode to air-containing Wenzel's mode. For a sunny-side-up like state, flat liquid film formation around the droplet edge was observed on the superhydrophobic surface after the wetting mode transition. This state seems to depend on the relation of surface energy values between the solid surface and liquid.
Polymer-immobilized colloidal crystal films have been fabricated by conventional spray coating of silica-acrylic monomer suspensions followed by UV curing. Controlling both the viscosity of the suspensions and the wettability of substrates enabled the synthesis of colloidal crystal films with smooth surfaces and brilliant structural colors due to Bragg diffraction. The structural colors could be controlled by particle concentrations as well as particle diameter. The wettability influenced the thickness of the coated film and it consequently affected the Bragg reflection intensity of the film. By the use of this effect, shapes were textured on a substrate having regions with different wettabilities by using a single spray coating.
This review introduces the basic properties and manufacturing methods of silicones. Silicones are widely used in materials for cosmetics such as oils, emulsifiers, film formers, gels, powders and powder treatments. Concrete examples of the behavior and characteristics of silicones in cosmetics are shown.
Security products such as banknote have a high risk of being counterfeited. In order for people to deter counterfeiting, security features must progress itself as counterfeit technologies change with the times. Especially, recent digital technologies allow anyone to counterfeit easily without any special skill. It becomes a new era that everyone is able to make a certain level of counterfeits and forgeries in house. This report briefly explains the outline of the latest security features which have been introduced mainly in the field of banknotes and passports.