Theory of dyeing

On the Theory of Dyes.—In carbon compounds absorption in the visible part of the spectrum, i.e. subjective colour, is conditioned by the presence of a so-called chromophoric group in the molecule. The nitroso-group is strongly chromophoric, the nitro-group much less so, whilst the azo-group is quite considerably chromophoric, but only in aromatic systems. Azomethane is colourless. 

The chemieal theory of dyeing supposes that a chemical combination of dyestuff and fibre takes place, and this view is, to a certain extent, supported by experimental proof, the researches of Knecht in this direction being especially worthy of attention. 

The behaviour of some acid dyestuffs also supports the chemical theory of dyeing. 

The mechanical theory of dyeing is based on the assumption that the molecules of colouring-matter leave the dye-bath and are mechanically deposited between the molecules of the fibre. 

Introduction to chemical constitution and colour, theory of dyeing, and classification of dyes... 

S OYKINC AND CHEMICAL TECHNOLOGY OF TEXTILE FIBRES Introduction to the theory of dyeing... 

As has already been explained, when dealing with the theory of dyeing, increase of temperature decreases the amount of dye adsorbed by the fibre at equilibrium. By increasing the kinetic energy of the molecules it does. 

The author is grateful to those who reviewed the Third Edition for their helpful suggestions and these have been taken into account in the preparation of the present book. Most chapters contain additional matter of current interest. The chapter dealing with the relationship between colour and chemical constitution has been expanded and an addition has been made in the form of an introduction to the theory of dyeing. The final paragraphs at the end of the book include an introduction to instrumental match prediction. 

Oprea, T.I., Kurunczi, L. and Timofei, S. (1997) QSAR studies of disperse azo dyes. Towards the negation of the pharmacophore theory of dye-fiber interaction Dyes S, Pigments, 33, 41-64. 

A discussion of the uptake of salt in the presence of dye must logically start from the present theory of dyeing of cellulose which can account for much of what is currently known about dye absorption equilibria to a first approximation. this theory, dye and salt are considered to exist in an aqueous solution in pores within the fiber. In addition, dye is assumed to be absorbed on absorption sites on the surface of the pores. According to this picture a form of (1) can be written for salt and for unbound dye, and in addition the equilibrium between the bound and unbound dye anions can be expressed by the equation... 

Berthollet s theory of dyeing was a chemical one. After criticising Macquer... 

Hellot s publications on dyeing and the theory of dyes are important. He... 

We have analyzed the nature of the dye-fiber interaction for 27 disperse azo dyes by means of several QSAR methodsbased on the pharmacophore theory of dye-fiber interaction. Hydrophobic effects were excluded because CLOGP gave a limited correlation, = 0.32. MTD (r = 0.924) and CoMFA (j-2 = 0.925 and = 0.776, LOO) results emphasized the importance of steric contributions for enhancing the affinity to cellulose fiber. CoMFA results apparently confirm the validity erf the pharmacophore theory of dye-fiber interaction. This was not surprising because similar results between CoMFA and MTD were reported in 1993. ... 

Disperse Azo Dyes. Towards the Negation of the Pharmacophore Theory of Dye-Fiber Interaction ... 

The theory of dyeing covers a wide range of subjects, mainly in the area of physical chemistiy. Some of the subjects included in dyeing theoiy are ... 

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