Colorants types

The chemistry of the three most important chemical classes of organic colorants, the azo, carbonyl and phthalocyanine classes, has been dealt with individually in Chapters 3-5 respectively. In this chapter, the chemistry of a further five chemical classes which are of some importance for specific applications is discussed. These classes are the polymethines, arylcarbonium ion colorants, dioxazines, sulfur dyes and nitro dyes. A section of this chapter is devoted to each of these, each individual section contains a description of the principal structural features which characterise the particular colorant type, together with an outline of the chemistry of the main synthetic routes. There are many other chemical types of dyes and pigments that do not fall into the categories previously mentioned, but which are neglected in this text either because they are commercially of little importance or because they have been less extensively investigated. 

The use of color by prehistoric peoples was also addressed in Willoughby s discussion of textiles found at the Mississippian temple mound sites of Etowah, Georgia and Spiro, Oklahoma (colored textiles. Kuttruff proposed that the complexity of these textiles including the colored patterning and design motifs is indicative of sophisticated artisanship and status differences that were expressed through clothing (73), but her study did not involve the identification of colorant types. Saltzman (14) identified madder as the dye plant that had been used to color some of the Spiro textiles. 

The introduction of auxochromes into the almost colorless anthraquinone permits the tailoring of compounds to cover nearly all shades of dye colors types and positions of the substituents in the molecule determine the hue. As a rule the bathochromic shift in simple anthraquinones increases with increasing basicity of the substituents. This generalization is clearly shown by the wavelengths of the longest wavelength absorption maximum of anthraquinones mono substituted in the 1-position [1] (Table 3.5) ... 

Figure 4.11. Graphic representations of protein 3D structure. Three-dimensional graphics of hen s egg-white lysozyme as visualized with RasMol (first and second rows, ILYZ.pdb) and Cn3D (third row, ILYZ.val) are shown from left to right (color type) in wireframe (atom), spacefill (atom), dots (residue), backbone (residue), ribbons (secondary structure), strands (secondary structure), secondary structure (secondary structure), ball-and-stick (residue), and tubular (domain) representations.

Lewis bases are species with available electrons that can be donated to form new bonds. Lewis acids are species that can accept these electron pairs to form new bonds. Since a Lewis acid accepts a pair of electrons, it is called an electrophile, from the Greek words meaning lover of electrons. A Lewis base is called a nucleophile, or lover of nuclei, because it donates electrons to a nucleus with an empty (or easily vacated) orbital. In this book, we sometimes use colored type for emphasis blue for nucleophiles, green for electrophiles, and occasionally red for acidic protons. 

A quantitative composition, including the name and amount of each active and inactive ingredient contained in the drug product, should be provided. In addition, an overall description of the dosage form should be included. This should be in sufficient detail to characterize it fully with regard to its type, release properties (i.e., immediate versus sustained or controlled release), and physical characteristics such as shape, color, type of coating, hardness, scoring, and identification marks. 

This combination of colorant types also helps explain the peculiar staining of the underarm portions of the silk historic garment. Pink-colored regions may be viewed as areas from which the yellow dye migrated in the presence of alkaline substances in the perspiration, and the yellow regions as areas to which this bleeding acid dye was transferred. 

Further studies into the possible effects historic cleaning methods had on garments could be valuable in explaining some fabric colorant behaviors presently exhibited by collected textile items of historical significance. It is recommended that the usefulness of x-ray analysis techniques to determine colorant type or residual effects of treatment be studied further. Tests similar to those conducted in this study could be done to test colorant responses to situations using a more refined color comparison method, such as the Hunter Color Difference Meter. 

Both soluble dyes and dispersible pigments are employed as colorants in inkjet inks. The choice of colorant type depends somewhat on the application and media to be used. For example, on plain copier paper, light that is reflected off the surface of the ink film... 

The ocular hypotensive effect of latanoprost appears to be independent of race, gender, age, iris color, type of glaucoma, or previous glaucoma therapy. 

If a technique is to exploit differences in pigmentation, it needs prior measurements of the light-absorbing characteristics of the algae. Hence, the action spectrum for fluorescence of chlorophyll a is a tool for identifying the color types of algae (i). 

Internal loop flow COLOR type compact loop reactor (diameter height = 1 1.1)... 

Colored type indicates the sublevel to which the last electron is added. 

Table 8.3 shows the partial orbital diagrams and ground-state electron configurations for the 18 elements in Period 4 (again with filled inner levels in brackets and the sublevel to which the last electron has been added in colored type). The first two elements of the period, potassium and calcium, are the next alkali and alkaline earth metals, respectively, and their electrons fill the 45 sublevel. The third element, scandium (Z = 21), is the first of the transition elements, those in which d orbitals are being filled. The last electron in scandium occupies any one of the five 3d orbitals because they are equal in energy. Scandium has the electron configuration [Ar] 4s 3d. ... 

Fabric Color Type of Electronic Natural to wearable integration wear... 

Colorant type Color index Concentration, % Shrinkage, mm/mm Shrinkage vs. natural, %... 

Color Type Chemical Base Common Pigment Designations Application Notes... 

Natural gas. See Methane gas Natural gasoline. See Gasoline Natural green 3. See Cl 75810 Natural iron oxides. See Ferric oxide Natural lead sulfide. See Lead sulfide Natural Liquid AP Carmine Colorant, Natural Liquid Carmine Colorant (Type 100, 50, and Simple). See Carmine (Coccus cacti)... 

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