Natural fish silver

Table 52 contains a comparative overview of Ti02-mica, basic lead carbonate, bismuth oxychloride, and natural fish silver pigments. Some further physical data are summarized in Table 53. 

Natural pearl essence is isolated as a silky lustrous suspension from fish scales. The organic pigment particles in the suspension are platelet-shaped with a very high aspect ratio (0.05 pm x 1-10 pm x 20-50 pm), and consist of 75-97% guanine and 3-25% hypoxanthine (natural fish silver) [5.122, 5.123, 5.128, 5.130]. 

Ti02-mica pigments are used in all color formulations of conventional pigments where brilliance and luster are required in addition to color, i.e., in plastics, coatings, printing, and cosmetics. Table 5.15 contains a comparative overview of Ti02-mica, basic lead carbonate, bismuth oxychloride, and natural fish silver pigments. Some further physical data are summarized in Table 5.16. 

Natural fish silver very low density high price nail lacquers... 

Natural fish silver needles, longish platelets 10-40 40-50 1.6... 

Natural fish silver Very low density High luster N ontoxic Light stable High price Low hiding power Limited availability Nail lacquers... 

Natural pearl essence (Essence d Oriente, Fish Silver) is a pigment suspension derived from fish scales, skin, or bladder. It is the oldest commercial pearl luster pigment, consisting mainly of a mixture of the purines guanine [73-40-5] (75-97%) and hypoxanthine [68-94-0] (25-3%). 

Natural polymers such as albumin, gelatin, fish glue, shellac, and gum arabic received attention up to the early 1900 s, after which time other materials such as bichromate, diazo compounds, iron salts, and silver halides were added to resins in order to hasten or accomplish their crosslinking. These systems were neither photopolymerization nor photocrosslinkable polymers. Instead, the added second component, when excited by light, produced a species which itself caused the formation of radical sites on a prepolymer or polymer chain which then led to cross-linking. 

The syntheses of AgNPs using fish liver oil were carried out by Khanna and Nair (2009). The reaction between silver salt and cod liver oil resulted in the formation of AgNPs. The prepared AgNPs gives a surface plasmon resonance at 433—436 nm in the UV-visible spectroscopy. The XRD confirms the particles formed are crystalline in nature and the TEM image confirms the average particle size as around 3—5 nm. This method was one of the eco-friendly methods for synthesis of nanoparticles without any drawbacks to the environment which could play a major role in future. 

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