your question shows that you are not familiar with the analysis of dyes . Why?

you cannot use the FTIR  method for an unknow dye  (s) before you check the purity and  purify it  (TLC, UV-Vis, NMR, GC/MS. The interpretation of a FTIR spectrum is only possible with a waterfree, pure dye (one spot in TLC and an exacr elemental analysis).

BUT , BE CAREFUL, Rubine Red on other dyes are protected  (patents ) .If you publish the composition without the permission of the company, the attorney on law will intent you a process.

Please launch google scholar and NOT google  and read the link (patent) about rubine red.

https://www.google.com/patents/US4522429

Do it the same for the above cited dyes in your question.

JRG

From my own experience I can say that the UV-vis  spectra are the most precise spectral specifications for dyes.

Quantitative determination can be made, knowing the molar extinction coefficient of the compound.

All your samples contain water (band at ≈3400 cm–1 can be assigned to the OH stretching vibrations of water molecules).

Best regards,

Olga Dolotova

Dear Chhavi,

What you need is the Colour Index

www.colour-index.com

This relates a very wide range of colour names and commercial product IDs to chemical structures

I insert your question again and give some comments:

I have 3 unknown dye samples from an industry. What a kind of a Company / Please name  and location.

The commercial names are

NAVY S2GR, YELLOW BROWN S2RI, RUBINE RD . I need the chemical composition of these dyes.

The name are not right! Why:

Rubine RD is Rubine RED,

Navy S2GR must be Permasil or  Blue NavyS2GR (see link)

http://www.worlddyevariety.com/disperse-dyes/disperse-blue-79.html

Please help to analyse the FTIR results of 3 unknown dye sample.?

give please the name of your FTIR spectrometer  and in what  (KBr  ....)you  obtain a spectrum of  your dyes. KBr must be always waterfree. Describe your FTIR protocol.

If you have a " lazy supervisor" please contact the chemistry department (analytical chemistry).

I agree fully with the answer of  Olga  and David.

BUT the C.I doesn't  contain all the trivial or commercial names.

According to my answer and the paper of  Olga  (see attachment  )  the molar ext. coeff. needs  exact elemental analysis  values for the concentration . (Waterfree or with x moles water)

On other pat you must test the solubility in different solvents for UV-Vis  and NMR.

TLC  (Thin Layer Chromatography) must be done at first because you can  see the impurities (1 to .... spots).. You must find an adequat mixture of solvents  for TLC.

The analysis of dyes (chem. composition ...) began 1880 to today.

JRG

here the copy of the Olga's paper as example for your future answer.