Pigment literature

General paint and pigment literature. There are traditional pigments for particular uses and binders. 

At this point, some comment on definition is overdue. Entry of the phrase high performance into the pigment literature appears to date from the mid 1960s, when... 

Various aluminium sulfates are described in the chemical and pigment literature aluminium sulfate (Al2[S04]3) alunite (KAl3[804]2[0H]g) alunogen (Al2[S04]2.18H20) alum (AI2. [804)3) ettringite (Ca6Al2[S04]3[0H],2.26H20). 

The pigment literature uses the terms burnt gypsum and plaster of Paris to a large extent synonymously Roller (2000), for example, has used the term burnt gypsum to describe the composition of pastiglia (plaster reliefs on paintings). 

Considerable confusion exists in the pigment literature over saffron and safflower (. v.) the latter was derived from Carthamus tinctorius L. and produced a red to yellow dye used to prepare lake colours. Antimonial saffron was a term for antimony(V) sulfide (q.v.). 

First, and perhaps foremost, are the members of the library staff at E. I. Du Pont de Nemours Co., Chemicals and Pigments Department, Jackson Laboratory, Deepwater, New Jersey, for their remarkable and enthusaistic assistance in culling literature. We particularly appreciate the efforts of Louise Del Signore, Dianne Cowperthwait, Evern Ford, Eleanor Price, Joanne Randolph, and Dot Toulson. 

The typical isocyclic ring E present in chlorophylls is susceptible to a number of different modifications such as epimerization, which produces stereoisomers by inversion of the configuration at C-13 of their parent pigments. These 13 -epichlorophylls, known as chlorophylls a and b, are minor pigments. They are considered artifacts produced in the course of handling plant extracts and sometimes are also found in small amounts in heated and deep-frozen vegetables, hi the old Fischer systan of nomenclature that can still be found in some literature, these epimers were named 10-epichlorophylls. 

As frequently mentioned in the literature, anthocyanins co-exist in equilibrium in four different forms. The pH conditions shift this equilibrium toward a variety of structural forms, with the direct consequences of color changes of these pigments. As a rule, at pH above 4, yellow compounds (chalcone form), blue compounds (quinoid base), or colorless compounds (methanol form) are produced. Anthocyanins have the highest stabilities at a pH between 1 and 2 since the flavylium cation is the most stable predominant form. 

Co-pigmentation of anthocyanins generally produces more intensely colored and more stable pigments than anthocyanin only. Two types of co-pigmentation reactions are mentioned in the literature. The first one involves intramolecular... 

Betacyanins and anthocyanins are the major hydrophilic pigments in onr diet, and most of the literature focusing on health essentially concerns anthocyanins — the largest group of water-soluble pigments in the plant kingdom. They belong to the... 

The wide distribution of chlorophylls throughout the plant kingdom facilitates the scrutiny of chlorophyll-rich vegetables for human nutrition with a view to their direct consumption. However, until now, little standardized information was available in the literature regarding the absolute total chlorophyll contents and the ratios of chlorophylls a and b in raw materials. The different analytical methods of extraction and quantification and the lack of data about moisture contents (that may vary considerably among varieties and preparations) can also influence the final contents of pigments. These factors have largely contributed to the discrepancies found in similar food samples. 

In spite of the fact that all of these values are quoted freely in the literature, it is only the median that seems to be of any physical significance, considering the typically unsymmetric particle size distributions of organic pigments. 

This section will discuss some important concepts from coloristic practice and the optical properties of pigmented systems. Space considerations permit a treatment of only the most vital concepts. The reader must consult the literature for further details and accounts of special problems [1], A review on the effect of crystal structure on color application properties was published [2],... 

The determination of flow properties taken during the pigmentation and processing of thermoplastics are described in the literature on polymers [132,133],... 

It has often been observed that the coloristic properties of an organic pigment are a function not only of the size of particles but also of their shape. This is due to the anisotropy of the optical properties in different crystallographic directions within the crystal forms of a pigment. In 1974 [5, 6], it was demonstrated that of the equally sized but differently shaped particles of beta copper phthalocyanine blue, the almost completely cubic, i.e., more or less isometric form produces greenish blue shades, while acicular forms are responsible for reddish blue hues. The optical behavior of ordered pigment particles in systems has been reported in the literature [7, 8]. 

The dominant role of the batch operation over the continuous process throughout the pigment industry is somewhat in contrast to the patent literature, which includes numerous proposals for complete azo pigment manufacture by the continuous process as well as descriptions of the partial steps, such as the diazotization or the coupling reaction. 

Only very few of these yellow and orange pigments have stimulated interest in terms of technical application. The patent literature, for instance, describes a pigment with the following structure (38) [2] ... 

Table 26 lists examples of tetrachloroisoindolinone and isoindoline pigments (for general literature, see also [24]). 

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