Photochemistry and photophysics of azo dyes

by Lisinka Martina Gina Jansen

Written in English
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Edition Notes

Thesis (Ph.D.) - Loughborough University, 1997.

Statementby Lisinka Martina Gina Jansen.
ID Numbers
Open LibraryOL17213484M

The term azo dyes is applied to those synthetic organic colorants that are characterized by the presence of the chromophoric azo group ().This divalent group is attached to sp 2 hybridized carbon atoms: on one side, to an aromatic or heterocyclic nucleus; on the other, it may be linked to an unsaturated molecule of the carbocyclic, heterocyclic, or aliphatic type. Spectrochimica Acta Part A 61 () – Photophysics of xanthene dyes in surfactant solution Benoy B. Bhowmika,∗, Papia Gangulyb a Department of Chemistry, Centre for Surface Science, Jadavpur University, Kolkata , India b Department of Chemistry, Maulana Azad College, Kolkata , India Received 3 June ; accepted 28 July Some azo dyes with this property (and which can revert slowly to the trans isomer in the dark) are used in sunglasses and car sunroofs. Many azo dyes, like Sudan red and scarlet red, can be used as biological dyes because they are fat- soluble and can be absorbed into fat cell tissues on microscope slides. Azo dyes form % of all. Azo dye Formation 20 Isomerisation of diazo compounds 20 Photochemistry of diazo compounds 21 Alkylation reactions of azo-phenols 21 Metal complexes of Azo dyes 25 Metal-Halogen Exchange Chemistry

  The use of light in medical treatment is nothing new. In the ancient world, roots of the plant Dorstenia were applied topically on to irritated skin which would clear following a few hours of sunshine. The active ingredient, psoralen, is now the basis of PUVA (psoralen + UVA) therapy used to treat the effects of psoriasis and other skin ailments.. Psoralen acts by . The simplest azo dyes are yellow, but changing the number of chromophores or the backbone structure can produce red, violet, blue and even black dyes. Azo dyes are used as textile colorants, and well as in industrial paints, printing inks, varnishes, plastics, crayons and other products. In recent years, many high performance azo pigments have. Contents Title Page Introduction Basis of colour Natural dyes Mauveine Colour fastness Dye classification Azo Dyes Protein Textile Dyes Cellulose Textile Dyes Synthetic Textile Dyes Fibre-Reactive Dyes References. Photophysics and photochemistry of side-chain substituted liquid crystalline polyaryl cinnamates. Azo-dye polymer-based modulation in total internal reflective Fabry-Perot geometry. Dynamical study of photoinduced anisotropy and orientational relaxation of azo dyes in polymeric films: poling at room temperature.

Three Step Synthesis of Azo Dye Alexa Harnagel, Meghan Reilly, Ashly Solis St. Catherine University St. Paul, MN Abstract Organol brown azo dye was synthesized and altered with functional group conversions to see the effect it would have on its color. This allowed for the testing of what reactions can be used to create new variations of azo dyes. Photochemistry of the Complexes and Organometallic Compounds of d-block Elements The Photochemistry of Metal Complexes An Aside: Redox Potentials Involved in Photoredox Reactions Organometallic Photochemistry 8 The Photochemistry of Alkenes Aims and Objectives Excited States of Alkenes Photochemistry • Photochemistry is the underlying mechanism for all of photobiology. When a molecule absorbs a photon of light, its electronic structure changes, and it reacts differently with other molecules. The energy that is absorbed from light can result in photochemical changes in the absorbing molecule, or in an adjacentFile Size: KB. These AZO Dyes consist a group i.e. called AZO group having two nitrogen atoms and this group (covalent bond) connects atomic ring compounds. The two Nitrogen atoms are bonded with each other and form -N=N- as part of their molecular structure. Azoic Dyes are found mainly in three colors and these are red, brown and yellow.1/5(1).

Photochemistry and photophysics of azo dyes by Lisinka Martina Gina Jansen Download PDF EPUB FB2

Discover the best Photochemistry Chemistry in Best Sellers. Find the top most popular items in Amazon Books Best Sellers. This is the best of the best in photochemistry and photophysics textbooks. I borrowed and renewed this book for the whole period in my graduate school.

In 04' I finally became an owner. It never fails me. The author Prof. Turro is of little doubt the authority in 5/5(4). Azo dyes are characterised by presence in the molecule of one or more azo groups —N = N—, which form bridges between organic residues, of which at least one is usually an aromatic nucleus.

Many Cited by: Azo dyes consisting of a diazotized amine coupled to an amine or a phenol and contain one or more azo (–N = N–) linkage comprise about half of all textile dyes used in the present textile industry. Catalytic Degradation of Organic Dyes in Aqueous Medium, Photochemistry and Photophysics - Fundamentals to Applications, Satyen Saha and Author: Muhammad Saeed, Muhammad Usman, Atta ul Haq.

This is a very timely book that provides an up to date presentation of photochemistry and photophysics in which the two subject areas are clearly interrelated. The central theme is that of the photoexcited molecule: a new species having the same atoms but different bonds, with different scope to react (or not) depending on which electronic.

Organic Photochemistry and Photophysics by V. Ramamurthy,available at Book Depository with free delivery worldwide. Featuring contributions from leading experts, Organic Photochemistry and Photophysics is a unique resource that addresses the organic photochemistry and photophysical behavior in aromatic molecules, thiocarbonyls, selected porphyrins, and metalloporphyrins.

The book presents theories pertaining to radiative and radiationless transitions. It describes excited-state. We have begun to investigate the photophysics and photochemistry of these dyes, with the eventual objective to develop methods for their photo- chemical degradation.

This paper focuses on the photochemical behavior of a representative azo dye, Acid Orange 7, also known as Orange 7. This dye is a widely used anionic monoazo dye [1].Cited by: Overview of the Photophysics and Photochemistry of Azomethine Dyes Singlet State Properties Absorption Characteristics.

In room temperature polar solvents the azomethine dyes have broad structureless, usually asymmetric, absorption bands in the visible spectral region with extinction coefficients in the region of 2 - 5× mol-1dm3cmFile Size: 59KB. Azo dyes make up 60–70% of all dyes used and are the most important chemical class of dyes.

Many of the dyes used on cotton are azo dyes (e.g., fiber reactive, direct, azoic). Some azo dyes, if absorbed by the human body, can undergo reduction decomposition to form carcinogenic amines due to enzymes in the body that have reduction properties.

Photophysics of Organometallics by Alistair J. Lees (Editor) Paperback () $ Ship Photophysics and Photochemistry of Organometallic Rhenium Diimine Complexes.- Exploitation of Luminescent Organometallic Rhenium(I) and Iridium(III) Complexes in Biological Studies.- Azo dyes play an important role as coloring agents in the Pages: This new edition of the classical text is thoroughly updated and rewritten, with special attention given to those topic areas that have experienced the most research activity and industrial development since publication of the second edition.

An extensive new section devoted to synthetic polyenes developed during the last decade, including poly(p-phenylenevinylenes), 5/5(3).

Photophysics and photochemistry of dyes bound to human serum albumin are determined by the dye localization Article (PDF Available) in Photochemical and. Azo dyes are organic compounds bearing the functional group R−N=N−R′, in which R and R′ are usually are a commercially important family of azo compounds, i.e.

compounds containing the linkage C-N=N-C. Azo dyes are widely used to treat textiles, leather articles, and some ally related to azo dyes are azo pigments, which are insoluble in water and.

Dye-substrate affinity. Dyes containing one or more azo groups (i.e. azo dyes) comprise by far the largest family of organic dyes. Prominent types are 1) acid dyes for polyamide and protein substrates such as nylon, wool, and silk; 2) disperse dyes for hydrophobic substrates such as polyester and acetate, and 3) direct and reactive dyes for cellulosic substrates such as cotton.

Organic Photochemistry and Photophysics edited by Vaidhyanathan Ramamurthy. Organic Photochemistry and Photophysics is a unique resource that addresses the organic photochemistry and photophysical behavior in aromatic molecules, thiocarbonyls, selected porphyrins, and metalloporphyrins.

Features: Presents a timely treatment of organic. Xenobiotics in the environment include a wide variety of compounds, e.g.

pesticides, drugs, textile dyes, personal care products, stabilisers, and many others. These compounds enter natural waters by rain washing of treated areas, via leaching through soil from places of application and via waste waters of manufacturing facilities or municipal waste waters (excretion of Author: Sarka Klementova.

Azo dyes are dyes with -N=N- azo structure as a chromophore. This category has only the following subcategory. Diarylide pigments ‎ (6 P) Pages in category "Azo dyes" The following 74 pages are in this category, out of 74 total.

This list may not reflect recent changes (learn more). Metal-complex dyes. Alizarine Yellow R. Amido black 10B. The U.S. Department of Energy's Office of Scientific and Technical Information. a) azo dyes b) anthraquinone dyes c) phthalocyanines (a) Azo dyes.

The azo dyes constitute the largest chemical class, containing at least 66% of all colorants. The characteristic feature is the presence in the structures of one or more azo groups, together with hydroxyl groups, amine and substituted amine groups as auxochromes.

Photophysics of some styryl thiazolo quinoxaline dyes in organic media Article in Journal of Photochemistry and Photobiology A Chemistry () October with 36 Reads.

Photochemistry-chemical reactions initiated by light-energy is absorbed or emitted by matter in discrete quanta called photons-absorption of light leads to an electronic excitation (ground state→excited state)-promote an e-like n→π∗ or π→π∗-most chemistry takes place from S1 and T1 excited states E = hν = hc/ λ.

The acid azo dyes possess affinity for wool and silk and are applied by essentially the same procedure used for the direct class. Tartrazine is a yellow acid azo dye discovered in and still in common use.

Get exclusive access to content from our First Edition with your subscription. Subscribe today. intermediates requires exclusion of air and moisture, photochemistry is very sensitive to colored or light absorbing impurities – either in the starting materials or formed during reaction.

Both may interfere with the photo processes and may kill the Size: KB. Dyes are used in almost every commercial product such as food, clothing, pigments and paints, etc. There are many different classes of dyes in which azo dyes are certainly one of the most important classes.

About half of the dyes used in industry are azo dyes. Azo dyes have the basic structure, Ar−N=N−Ar’, where Ar and Ar’ are two aromaticFile Size: KB. Photochemistry is the branch of chemistry concerned with the chemical effects of light.

Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from to nm), visible light (– nm) or infrared radiation (– nm).

In nature, photochemistry is of immense importance as it is the basis of photosynthesis, vision, and the. Aryl azo compounds. Aryl azo compounds are usually stable, crystalline species. Azobenzene is the prototypical aromatic azo compound. It exists mainly as the trans isomer, but upon illumination, converts to the cis isomer.

Aromatic azo compounds can be synthesized by azo coupling, which entails an electrophilic substitution reaction where an aryl diazonium cation is. Azo dyes organic chem 1.

Preparation of Methyl Orange By Dr. Robert Craig, ound Reading:Small Scale Syntheses, pp (azo dyes).McMurry, J., Organic Chemistry, 7th Ed., pp (UV-Vis spectroscopy)and (diazonium ions and their coupling reactions) [6th Ed.: pp] 2.

Direct Dyes and Acid dyes. PHOTOCHEM T he role of light in effecting chemical change has been recognized for many years. Indeed, the connection between solar energy and the biosynthesis of plant carbohydrates from carbon dioxide and water was known by the early 's.

Yet organic photochemistry was slow to develop as a well-understood and manageable Size: 2MB. $\begingroup$ @Klaus Warzecha I understand that the azo-dye absorbs a specific frequency of light and we see the complementary colour.

However, I am confused about WHAT absorbs the light. For e.g. in transition metals, there is a d-d transition of an electron. I asked my teacher, she told me that it has something to do with the electron cloud of the ring that absorbs a frequency.

The term azo dyes is applied to those synthetic organic colorants that are characterized by the presence of the chromophoric azo group ().This divalent group is attached to sp 2 hybridized carbon atoms: on one side, to an aromatic or heterocyclic nucleus; on the other, it may be linked to an unsaturated molecule of the carbocyclic, heterocyclic, or aliphatic type.Dye - Dye - Development of synthetic dyes: Perkin’s accidental discovery of mauve as a product of dichromate oxidation of impure aniline motivated chemists to examine oxidations of aniline with an array of reagents.

Sometime between andFrench chemist François-Emmanuel Verguin found that reaction of aniline with stannic chloride gave a fuchsia, or rose-coloured.

Keywords: Azo dye, Para red derivatives, Diazonium salts reaction, Synthesis Introduction Azo dyes contain at least one nitrogen-nitrogen double bond (N=N); however many different structures are possible 1. Monoazo dyes have only one N=N double bond, while diazo and triazo dyes contain two and three N=N double bonds, respectively.