To examine the strengths and limitations of the time-dependent density functional theory in calculating the absorption wavelengths of dye, 130, non-radical, radical and biradical coloured organic compounds, including perylenimide, porphyrin, azobenzene, quinone, croconaine, squaraine and push–pull-type colorants, were randomly selected. The first intense electronic transitions were satisfactori...

The title compound, C(12)H(10)O(4)S, is a phenolic color developer used for leuco colorants. The two benzene rings with substituent hydr-oxy groups are nearly perpendicular to each other [dihedral angle = 91.5 (1)°]. There are inter-molecular O-H⋯O hydrogen bonds between an OH group of one mol-ecule and a sulfonyl O atom of a neighboring mol-ecule. One mol-ecule is hydrogen bonded to four symme...

Photoluminescence has been exploited to characterize materials non-destructively since the early development of scientific studies on archaeological and cultural heritage materials [1]. First used as tool for qualitative visual examination of objects, luminescence spectroscopy, carried out at macroand micro-scale, allowed characterizing luminescence properties of cultural heritage and artists’ ...

Abstract Overexposure to food colorants above the allowed daily intake (ADI) level can provoke hyperactivity and other disturbed behaviors especially in children. Two new methods were developed separate five synthetic colorants, which Tartrazine (E102), Sunset Yellow (E110), Allura Red (E129), Carmoisine (E122), Brilliant Blue (E133). They are labeled on a large variety of commercial products E...

Background/Objectives: The utilization of natural colorant can improve food appeal. This study determined the potential Clitoria ternatea flower extract as a substitute for synthetic colorants. Methods: researchers prepared gummy candies using 100mL aqueous extracts from various weight samples C. flowers. Fifty candy eaters with different age brackets were randomly chosen respondents this study...

This paper reports the studies available on the characterization and chemical/biochemical analysis of natural dyes; extraction of colorants from different natural sources; effects of different mordants and mordanting methods; conventional and non-conventional methods of natural dyeing; physico-chemical studies on dyeing process variables and dyeing kinetics; development of newer shades and anal...

New 1,2,4-triazole colorants were obtained, in high yields, by coupling 3-ethylthio-5-cyanomethyl-4-phenyl-1,2,4-triazole (1) with diazotized aniline derivatives 2, 4 and 6. The azo dyes prepared in this work may exist in three tautomeric forms. We found that the tautomerism is influenced mainly by the nature of substituent at the para position of the aniline coupling component. This tautomeris...

An efficient, sensitive and fast method was developed based on an ultrasound-assisted extraction followed by an ion-pair dispersive liquid-liquid microextraction (USAE-IP-DLLME) for the simultaneous determination of five commonly used synthetic sulfonate dyes (tartarazine, quinoline yellow, sunset yellow, azorubine, and brilliant blue) in ice cream samples using high performance liquid chromato...