Analysis of the properties of active dyes

Abstract

The range of active dyes used for dyeing materials made of natural plant fibers includes about a thousand brands belonging to more than 50 groups all over the world. Among them, bifunctional active dyes are of research and practical interest. They allow to obtain intense and durable bright color scheme due to their chemical specificity. Also they save not only the dye itself, but a number of additional textile auxiliary substances, which in turn is favorably affects the environmental performance of the dyeing process. The authors present in the article the analysis of experimental data, which make it possible to obtain or verify chemical, physicochemical and coloristic indicators of the properties of mono-, bi- and polyfunctional active dyes. Conclusions are made on the dependence of these indicators in the process of dyeing textile materials according to several technologies most often used in finishing production.

Karakterisasi Elektrokimia Ekstrak Klorofil dari Daun Salam (Syzgium polyanthum) pada pH Basa sebagai Sensitizer pada Dye Sensitized Solar Cell (DSSC)

“…Pewarna berfungsi menyerap cahaya untuk menghasilkan elektron dan mengirimkan elektron ke pita konduksi semikonduktor [6]. Setiap pewarna harus memiliki karakteristik khusus seperti: (a) mengandung gugus kromofor yang dapat memberikan karakteristik zat warna,(b) absorpsi pada spektra kisaran daerah cahaya tampak (400-700 nm), (c) mengandung gugus karboksil atau hidroksil yang dapat mengikat permukaan semikonduktor dengan baik untuk mempermudah proses transfer elektron ke celah pita konduksi semikonduktor, (d) memiliki stabilitas yang baik dalam menyerap foton, (e) energi HOMO (Highest Occupied Molecular Orbital) harus lebih rendah dari potensial redoks elektrolitnya, dan (f) energi LUMO (Lowest Unoccupied Molecular Orbital) harus cukup tinggi dari pita konduksi semikonduktor [7][8][9].…”

Investigation on dyeing mechanism of modified cotton fiber

“…They are some of the most widely used dyes in cotton fabric dyeing. [4][5][6][7][8][9] Recently, a large amount of inorganic salts were added to the dyeing process to eliminate electrostatic repulsion and made the dye molecules come into close contact with the fabrics' surface. 10,11 However, aer dyeing, inorganic salts still existed in dyeing wastewater, which increased the difficulty of treatment and dyeing cost.…”