Colorants Ultramarine Blue

Zeolites are structurally related to colorless sodalite, Na4Cl[Al3Si3012], and to deeply colored ultramarines. These have aluminosilicate frameworks that enclose cations but no water molecules (Fig. 16.25). Their special feature is the additional presence of anions in the hollows, e.g. Cl-, S()4, S2, or S. The two last-mentioned species are colored radical ions (green and blue, respectively) that are responsible for the brilliant colors. The best-known representative is the blue mineral lapis lazuli, Na4S (.[Al3Si3012], which is also produced industrially and serves as color pigment. 

In exterior exposure, PS yellows somewhat, due to UV radiation. In order to shield the plastic from degradation in UV light, it is also supplied in combination with UV absorbents. This prolongs the lifetime of the products by a factor of three to five. Grades which contain UV absorbents are slightly yellowish, a fault which may be corrected by adding transparent blue colorants such as soluble dyes or Ultramarine Blue [36]. 

Parabens are approved for use in oral solution and suspensions at a concentration of 0.015% to 0.2% w/v. Due to their low solubility, the sodium salts of parabens are often used in aqueous formulations. The parabens are most effective in the pH range of 2 to 6, and their antimicrobial activity decreases with increasing pH. Additionally, they are very unstable at pH 8 or above in solution. Methyl paraben has also demonstrated incompatibility with sorbitol and may show some discoloration in the presence of iron. The absorption of methylparaben by plastics has been reported with the amount absorbed being dependent upon the type of plastic and vehicle. However, no absorption has been reported for low density polyethylene (LDPE) or high density polyethylene (HDPE) containers. Certain coloring agents such as yellow iron oxide, ultramarine blue, and aluminum silicate can extensively absorb ethyl paraben in simple aqueous systems, thus reducing its preservative efficacy. 

Anotherdaxs of framework aluminosilicates is the ultramarines They arc characterized by an open framework and intense colors. They differ from the previous examples by having "free" oruons and no water in the cavities. Ultramarine blue, which is the synthetic equivalent of the mineral lapis lazuli, contains radical unions. 

Exempt colors do not have to undergo formal FDA certification requirements, hut are monitored for purity. The colorants exempt from FD C certification are annatto extract, /i-carolene, beet powder, 0-apo—8 -carntenol. canlhaxanthin. caramel, carmine, carrot oil. cochineal extract, cottonseed Hour, ferrous gluconate, fruit juices, grape skin extract, paprika, paprika oleoresin. riboflavin, saffron, titanium dioxide, turmeric, turmeric oleoresin. ultramarine blue, and vegetable juices. See also Colorants (Foods). 

Smoke shells and rockets are used to produce smoke clouds for military signaling and, in daylight fireworks, for ornamental effects. The shell case or rocket head is filled with a fine powder of the desired color, which powdered material need not necessarily be one which will tolerate heat, and this is dispersed in the form of a colored cloud by the explosion of a small bag of gunpowder placed as near to its center as may be. Artificial vermilion (red), ultramarine (blue), Paris green, chrome yellow, chalk, and ivory black are among the materials which have been used, but almost any material which has a bright color when powdered and which does not cake together may be employed. 

Ultramarine blue has poor opacity but high tinting strength, high heat resistance, and good alkali resistance. It is primarily used as a tinting color, and when added to whites makes them look whiter by giving them a bluish cast. 

Ultramarine Blues, Violets, and Pinks. Ultramarine pigments are noted for their rich colors, moderate heat stability, chemical resistance, bleed resistance, opacity, weatherability, and attractive economics. They are known to be sensitive to an acidic environment, which may have some effect on their utility. Ultramarine pigments are some of the very old and venerated colorants since they were originally naturally occurring materials, mainly in Middle Eastern countries. Sodium is a constituent of ultramarine pigments, which makes it unique as sodium does not usually appear as a component of color pigments. 

An increasing number of colored inorganic pigments are FDA-compliant. Historically, yellow iron oxide, red iron oxide, black iron oxide, zinc ferrite, burnt umber, raw and burnt sienna, channel carbon black, chromium oxide green, ultramarine blue, cobalt blue and copper chrome black have enjoyed FDA—compliant status, under 21 CFR 178.3297, Colorants for Polymers . More recently, the FDA has been successfully petitioned with regard to nickel titanium yellow, chrome titanium yellow, and cobalt green under 21 CFR 170.39, Threshold of Regulation for Substances Used in Food-Contact Articles . 

MS 965. One can readily assign bands to ultramarine blue and white lead. In addition, an occasional, isolated blue chip was found in the sample. The spectra of these blue chips matched reference spectra of ultramarine blue obtained from the Forbes Collection. Therefore, a red pigment must be present with the blue to obtain a purple color. 

In many applications ultramarine blue is stable to around 400 °C, violet to 280 °C and pink to 220 °C. All have excellent light fastness with a 7-8 rating (full and reduced shades) on the International Blue Wool Scale. Color fade attributed to light exposure or moderate heat is almost always caused by acid attack. Ultramarines react with all acids, and if there is sufficient acid, the pigment is completely decomposed, losing all color, to form silica, sodium and aluminum salts, sulfur, and hydrogen sulfide. Evolution of hydrogen sulfide with acids is a useful test for ultramarine. 

Another class of framework aluminosilicates is the ultramarines. They are characterized by an open framework and intense colors. They diller from the previous examples by having free anions and no water in the cavities. Ultramarine blue, which is the synthetic equivalent of the mineral lapis lazuli, contains radical anions. SjT and ST. The dominant Sj gives rise to its blue color. Ultramarine green also contains the.se two anions but in comparable amounts. Although these two anions are also found in ultramarine violet and pink, the characteristic color is due to a third species, perhaps or S - - Structurally related, but colorless, minerals such as sodalite (containing chloride unions) and noselite (containing sulfate anions) are sometimes included in the broad category of ultramarines. 

Prior to the discovery of Prussian blue, there were three blue pigments available to painters azurite [ 03(011)2(003)2], smalt (a complex cobalt and arsenic compound), and ultramarine blue, which has the complex formula of CaNa7Al6Si6024S04. Prussian blue quickly came to be valued by painters for the intensity and transparency of its color, and it is commonly found in works painted after the early 1700s. 

In principle, deprotonation of any of the sulfanes gives polysulfide anions In practice, this route is not employed and rather fewer anions are known compared with the sulfanes. It was established last century that sulfur dissolves in basic media to give intensely colored (often blue) solutions. The well-known polysulfide solution [NH4]2Sjt, which contains mostly X = 4 and 5, is obtained by bubbling H2S through a suspension of sulfur in ammonium hydroxide. It is accepted nowadays that the blue coloration of many of these solutions is a consequence of the 83 radical. This species has characteristic EPR, visible, and Raman spectra that have enabled its detection in a variety of solutions including liquid ammonia,DMF, and HMPA. 82 can be introduced as an impurity into alkali metal halides. In lapis lazuli (lazurite that is made synthetically as ultramarine blue Na8[Al68i6024]8 , n = 2-4), the blue color is due to the presence of 83 radicals, which has also been identified by Resonance Raman Spectroscopy ... 

The ultramarines range in color from a medium shade blue through violet to pink. A household example of an ultramarine blue in full shade is the Milk of Magnesia bottle. Standard grades of ultramarine pigments (uncoated) react with polyacetal resins, and I have observed color drift of these pigments in PC and PA 6/6. Some properties of ultramarine pigments are listed in Table 1. 

The next step in the validation of the production method is the reproducibility of the lots produced. This had to be compared to the reproducibility of the batch process. The best way to control this is to check the color parameters, and more precisely on the Avalues of these color parameters. The references taken were the medium sample values. The samples are supposed to cover 2 years of production from specific Ultramarine Blue pigments. 

This statement was taken into account in the continuous production process and Figure 1 illustrates this approach. As you can notice, by building up this product range, it becomes possible to cover most of the color spectrum of Ultramarine Blue pigments. 

A continuous production process of Ultramarine Blue pigment answers the demand on color as well as existing batch production process, improves on consistency and helps in final formulation. 

Properties Ultramarine blue color Colormatch EDC-30268 [Plasticolors]... 

Chem. Descrip. Ultramarine blue CAS 57455-37-5 EINECS/ELINCS 309-928-3 Uses Pigment for coloring thermoplastic resins, rubber compds., paints, printing inks, artists colors, rooting granules, food-contact polymers Reguiatory FDA 21CFR 178.3297... 

Phenylazo)-2-naphthylamine Ponceau 3R Red sandalwood (Pterocarpus santalinus) Rhodoxanthin Riboflavin Riboflavin-5 -phosphate sodium Rubixanthin Saffron (Crocus sativus) Sandalwood (Santalum album) Tannic acid Tartrazine Titanium dioxide Turmeric (Curcuma longa) Turmeric (Curcuma longa) extract . Ultramarine blue Vegetable carbon Violoxanthin Xanthophyll colorant, food processing Carbon black... 

The colors of a number of inorganic species arise from charge transfer. For example, the d-levels of Cr(VI) and Mn(VII) are empty and their compounds ought to be colorless. However, charge transfer leads Cr04 and MnOT to be strongly colored. These transitions also cause the intense colors in blue sapphire and ultramarine. 

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