Effect of calcination temperature and Ti substitution on optical properties of (Fe,Cr)2O3 cool black pigment prepared by spray pyrolysis

Ti-Dispersed (Fe,Cr)2O3 cool black pigment particles synthesized by a spray pyrolysis process showed improvement in NIR reflectance by about 10.0% and heat-shielding performance.

Highly Effective Protocol for Differentiation of Induced Pluripotent Stem Cells (iPS) into Melanin-Producing Cells

Melanin is a black/brown pigment present in abundance in human skin. Its main function is photo-protection of underlying tissues from harmful UV light. Natural sources of isolated human melanin are limited; thus, in vitro cultures of human cells may be a promising source of human melanin. Here, we present an innovative in vitro differentiation protocol of induced pluripotent stem cells (iPS) into melanin-producing cells, delivering highly pigmented cells in quantity and quality incomparably higher than any other methods previously described. Pigmented cells constitute over 90% of a terminally differentiated population and exhibit features characteristic for melanocytes, i.e., expression of specific markers such as MITF-M (microphthalmia-associated transcription factor isoform M), TRP-1 (tyrosinase-related protein 1), and TYR (tyrosinase) and accumulation of black pigment in organelles closely resembling melanosomes. Black pigment is unambiguously identified as melanin with features corresponding to those of melanin produced by typical melanocytes. The advantage of our method is that it does not require any sophisticated procedures and can be conducted in standard laboratory conditions. Moreover, our protocol is highly reproducible and optimized to generate high-purity melanin-producing cells from iPS cells; thus, it can serve as an unlimited source of human melanin for modeling human skin diseases. We speculate that FGF-8 might play an important role during differentiation processes toward pigmented cells.

PERFORMANCE TEST AND HEAT RESISTANCE OF PHYSICAL AND CHEMICAL COATED IRON OXIDE BLACK PIGMENT

The current development strategy of inorganic pigments is to develop technologies, such as high coloring ability, low oil absorption, easy dispersion, heat resistance, and nontoxicity. As the largest colored inorganic pigments, iron oxide pigments are widely used in building materials, coatings, rubber, plastics, paint, etc. In this paper, black iron oxide pigment was used as the carrier, and alumina substance was used as the support. Precipitation method was used to synthesize the aluminum oxide-coated iron oxide black composite pigment under different experimental conditions, and the coated iron was studied by XRD, SEM and TEM characterization methods. The structure of the black pigment, discuss the influence of the coating temperature, reaction pH, coating method, neutralizing acid and other factors on the microstructure of the composite material and the performance of the pigment. The experimental results show that, through co-current coating, the temperature of the reaction system of 80∘C and the reaction pH of 10–11 are the best parameters for coating. The oil absorption, tinting power, hiding power and dispersion power of the coated iron black were tested, and the performance of the iron black pigment was greatly improved after the coating. The heat resistance and light fastness of iron black were tested through the color difference change experiment. The experimental results showed that the heat resistance and light fastness of iron black pigment showed good performance after coating.

Characterization of brown-black pigment isolated from soil bacteria, Beijerinckia fluminensis

Melanin is a ubiquitous pigment found in most organisms it is a dark-brown or black pigment formed by the oxidation of phenolic compounds. They are negatively charged amorphous compounds having quinone groups. In this study; melanin-producing microorganism was isolated from soil obtained from iron ore mine. The soil was enriched in modified Ashbys glucose broth for 15 days at 30°C further to which it was isolated on modified Ashbys agar at 30°C for seven days; the colonies showing pigmentation were selected for further study. Conditions were optimized for maximal production of melanin pigment. The effect of carbon nitrogen tyrosine and metal salts on pigment production was studied. Alkaline conditions were used to extract the pigment from cells, further characterized by UV-VIS spectroscopy for λ-max. FTIR was done to identify the native functional groups and XRD was performed to determine the melanins structure. TGA analysis was done to check its thermal stability. SEM was carried out to check the size and shape of the melanin pigment. The melanin pigment was also analyzed for UV protectant property which was studied by exposure of both melanized and non-melanized cells to UV light at 254nm. Key words: Beijerinckia fluminensis iron ore soil melanin and UV-protection.

Intensity Values of Terrestrial Laser Scans Reveal Hidden Black Rock Art Pigment

The intensity values of terrestrial laser scanning (TLS) can be used to reveal painted black rock art behind graffiti and moss. The effect was observed in Gumahon cave in Peñablanca, Philippines where previously unnoticed black pigment was exposed underneath moss, red and white painted graffiti, and etched name graffiti. The application of TLS intensity values for this purpose has not, to our knowledge, been previously reported. The significance of this finding is that archaeologists are provided a new method of detecting obfuscated rock art that can aid interpretation. The method can be applied in similar contexts as black painted rock art is common in limestone caves across Southeast Asia and Micronesia, but also ubiquitous globally.

THE EFFECT OF MILLING TIME AND PERCENTAGE OF DISPERSING AGENT ON THE CHARACTERISTIC OF SOLVENT-BASED BLACK PAINT FROM CARBON BLACK PIGMENT

THE EFFECT OF MILLING TIME AND PERCENTAGE OF DISPERSING AGENT ON THE CHARACTERISTIC OF SOLVENT-BASED BLACK PAINT FROM CARBON BLACK PIGMEN. The need for black paint made from carbon black pigment increasing year by year especially in the automotive world. The production of black paint is performed by milling the resin, pigment, additive/dispersing agent, and solvent. In the manufacturing process, it takes a relatively long time with precise dispersing agent composition toward pigment to get the product with blackness/solid black according to the expected quality. This work aims to study the role of the milling time of carbon black fw 200 beads on a 3 liter ball mill and the percentage of dispersing agents on paint color quality, especially blackness. The variations in milling time were 36, 48, and 60 hours and the weight percentage of dispersing agent toward pigment were 80%, 100%, and 120%. The optimum results obtained are at the milling time of 48 hours and on the percentage of dispersing agent of 120% with the product characteristics fulfills the requirement namely: 10 μm of particle fineness, 111.5 krebs unit of viscosity, 36.97% of solid content, 0.9839 gr/cc of specific gravity with desirable solid black color.