C.I. Acid Orange 6

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  • Identifiers

    CAS number
    547-57-9

    Molecular formula
    C12H9N2NaO5S

    SMILES
    C1=CC(=CC=C1N=NC2=C(C=C(C=C2)O)O)S(=O)(=O)[O-].[Na+]

    Safety labels

  • Odor profile

    Fragrance
    Odorless 83.19%
    Savory 24.51%
    Cooked 24.0%
    Bitter 20.97%
    Burnt 20.87%
    Roasted 20.32%
    Meaty 19.64%
    Milky 13.94%
    Pungent 12.86%
    Phenolic 11.96%

     

    Flavor
    Bitter 87.78%
    Odorless 34.74%
    Nitrile 21.19%
    Bland 21.06%
    Mild 19.64%
    Bread crust 19.44%
    Taco 19.32%
    Very strong 19.26%
    Roasted peanuts 18.94%
    Indole 18.87%

     

    Odor impact est.
    Low

  • Properties

    pKa est.
    7.12 (neutral)

    Molecular weight
    316.27 g/mol

    Flash point

    • 243.57 ˚C est.

  • Synonyms

    • 547-57-9
    • C.I. Acid Orange 6
    • DTXSID70873925
    • RefChem:1080549
    • DTXCID601506491
    • Tropaeolin O
    • ACID ORANGE 6
    • Resorcinol yellow
    • Chrysoine
    • Chrysoine S
    • Tropaeoline
    • Resorcin yellow
    • Chrysoine Extra
    • Tropaeoline O
    • Chrysonine S
    • Tropaeolin R
    • Chrysoine N
    • Chrysonis S
    • Gold Yellow
    • Resorcine Yellow
    • Tropaelin-O
    • Tropeolin O
    • Chrysoin G
    • Sodium azoresorcinolsulfanilate
    • Yellow T
    • Curol Orange G
    • Dermina Yellow G
    • Orange Acid G
    • Neklacid Yellow G
    • Tropaeolin O sodium salt
    • Eniacid Yellow RS
    • Hispacid Yellow CG
    • Resorcinol Yellow A
    • Eurocert Chrysoine S
    • Tertracid Yellow TRO
    • Naphthazine Yellow RP
    • Acid Phosphine G New
    • NSC 10441
    • Chrysoine resorcinol
    • Chrysoine Extra Pure A
    • Chrysoine S Extra Pure
    • 2,4-Dihydroxyazobenzene-4'-sulfonate sodium salt
    • C.I. Food Yellow 8
    • Acid Leather Yellow PGW
    • Resorcine Yellow O Extra
    • Cetil Chromine Yellow GR
    • CI 13015
    • CI 14270
    • Chrysoin S
    • Chrysoin S Specially Pure
    • Benzenesulfonic acid, 4-((2,4-dihydroxyphenyl)azo)-, monosodium salt
    • ACME Yellow Acid Yellow RS
    • MFCD00007499
    • Tropaeolene (Biological Stain)
    • Sodium 4-(2,4-dihydroxyphenylazo)benzenesulphonate
    • NF91VMI73L
    • C.I. 14270
    • E 103
    • Na 4-(2,4-diOHphenylazo)benzenesulphonate
    • 4-((2,4-Dihydroxyphenyl)azo)benzenesulfonic acid, monosodium salt
    • C.I. Acid Orange 6, monosodium salt
    • 2,4-Dihydroxyazobenzene-4'-sulfonic Acid Sodium Salt
    • sodium;4-[(2,4-dihydroxyphenyl)diazenyl]benzenesulfonate
    • C Yellow 12
    • Chrysoin
    • TropaeolinO
    • Benzenesulfonic acid, 4-(2-(2,4-dihydroxyphenyl)diazenyl)-, sodium salt (1:1)
    • E 103 (dye)
    • NSC-10441
    • EINECS 208-924-8
    • UNII-NF91VMI73L
    • Sodium (E)-4-(2, 4-Dihydroxyphenyl)diazenyl)benzenesulfonate
    • 2,4-Dihydroxyazobenzene-4'-sulfonate Sodium Salt; Acid Leather Yellow PGW;
    • 2,4-Dihydroxyazobenzene-4-sulfonic acid sodium salt
    • AO6 dye
    • Monosodium 4-((2,4-dihydroxyphenyl)azo)benzenesulfonate
    • p-((2,4-Dihydroxyphenyl)azo)benzenesulfonic acid, sodium salt
    • FOOD YELLOW 8
    • Benzenesulfonic acid, p-((2,4-dihydroxyphenyl)azo)-, sodium salt
    • TROPAEOLIN O [MI]
    • SCHEMBL94484
    • SCHEMBL144371
    • orb1987417
    • orb3025954
    • SCHEMBL29555012
    • MSK5808
    • p-(2,4-Dihydroxyphenylazo)benzenesulfonic acid, sodium salt
    • HY-D0305
    • CCG-55589
    • AKOS004901443
    • AKOS030228520
    • FT01468
    • AS-82936
    • SY010454
    • CS-0010217
    • NS00043852
    • R0010
    • Sodium 2,4-Dihydroxyazobenzene-4'-sulfonate
    • ST51039878
    • E70391
    • Q60479
    • SR-01000644607-1
    • F9995-1411
    • 4-([2,4-Dihydroxyphenyl]azo)benzenesulfonic acid sodium salt
    • Sodium 4-[(2,4-dihydroxyphenyl)diazenyl]benzene-1-sulfonate
    • 4-[(2,4-dihydroxyphenyl)diazenyl]benzenesulfonic acid, sodium salt
    • 547-57-9

  • Applications

    Acid Orange 6 (CAS 547-57-9) is an azo acid dye primarily used for coloring protein fibers such as wool and silk, and is also suitable for certain polyamide (nylon) fibers under acidic dyeing conditions; it is employed for leather coloration as well. In industrial manufacturing, it serves as a dye and can function as an intermediate in the synthesis of other azo dyes and pigments. It is used as a colorant in inks and coatings for paper, plastics, and related polymer substrates. Additionally, it may be used in research and development or analytical contexts as a reference dye or colorant standard.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 23.49
    methanol 28.42
    isopropanol 18.66
    water 0.02
    ethyl acetate 17.35
    n-propanol 25.97
    acetone 69.97
    n-butanol 20.75
    acetonitrile 15.32
    DMF 131.77
    toluene 1.28
    isobutanol 7.44
    1,4-dioxane 36.31
    methyl acetate 27.86
    THF 157.64
    2-butanone 102.62
    n-pentanol 12.33
    sec-butanol 40.79
    n-hexane 0.03
    ethylene glycol 7.82
    NMP 57.72
    cyclohexane 0.07
    DMSO 133.25
    n-butyl acetate 9.41
    n-octanol 8.04
    chloroform 0.47
    n-propyl acetate 12.1
    acetic acid 19.92
    dichloromethane 0.68
    cyclohexanone 58.57
    propylene glycol 31.89
    isopropyl acetate 14.26
    DMAc 206.9
    2-ethoxyethanol 82.5
    isopentanol 10.56
    n-heptane 0.13
    ethyl formate 14.33
    1,2-dichloroethane 1.23
    n-hexanol 8.93
    2-methoxyethanol 198.22
    isobutyl acetate 2.63
    tetrachloromethane 0.04
    n-pentyl acetate 11.11
    transcutol 216.1
    n-heptanol 7.83
    ethylbenzene 0.55
    MIBK 16.27
    2-propoxyethanol 69.43
    tert-butanol 15.48
    MTBE 8.14
    2-butoxyethanol 35.45
    propionic acid 17.68
    o-xylene 0.99
    formic acid 16.24
    diethyl ether 8.53
    m-xylene 0.76
    p-xylene 0.71
    chlorobenzene 0.56
    dimethyl carbonate 11.63
    n-octane 0.08
    formamide 81.59
    cyclopentanone 83.0
    2-pentanone 51.82
    anisole 7.68
    cyclopentyl methyl ether 10.76
    gamma-butyrolactone 54.99
    1-methoxy-2-propanol 163.19
    pyridine 23.4
    3-pentanone 21.47
    furfural 39.35
    n-dodecane 0.14
    diethylene glycol 49.51
    diisopropyl ether 1.24
    tert-amyl alcohol 26.55
    acetylacetone 61.21
    n-hexadecane 0.17
    acetophenone 12.55
    methyl propionate 24.84
    isopentyl acetate 7.55
    trichloroethylene 3.57
    n-nonanol 8.75
    cyclohexanol 13.41
    benzyl alcohol 10.32
    2-ethylhexanol 3.72
    isooctanol 4.52
    dipropyl ether 5.82
    1,2-dichlorobenzene 0.57
    ethyl lactate 18.3
    propylene carbonate 13.47
    n-methylformamide 64.3
    2-pentanol 15.28
    n-pentane 0.04
    1-propoxy-2-propanol 52.91
    1-methoxy-2-propyl acetate 26.8
    2-(2-methoxypropoxy) propanol 42.61
    mesitylene 0.5
    ε-caprolactone 34.87
    p-cymene 0.89
    epichlorohydrin 44.71
    1,1,1-trichloroethane 0.37
    2-aminoethanol 26.15
    morpholine-4-carbaldehyde 92.76
    sulfolane 73.43
    2,2,4-trimethylpentane 0.06
    2-methyltetrahydrofuran 31.45
    n-hexyl acetate 13.57
    isooctane 0.03
    2-(2-butoxyethoxy)ethanol 68.95
    sec-butyl acetate 7.31
    tert-butyl acetate 17.13
    decalin 0.05
    glycerin 52.69
    diglyme 95.11
    acrylic acid 15.09
    isopropyl myristate 6.54
    n-butyric acid 20.38
    acetyl acetate 8.43
    di(2-ethylhexyl) phthalate 5.38
    ethyl propionate 10.24
    nitromethane 76.59
    1,2-diethoxyethane 31.61
    benzonitrile 5.89
    trioctyl phosphate 4.31
    1-bromopropane 0.61
    gamma-valerolactone 133.33
    n-decanol 6.58
    triethyl phosphate 3.91
    4-methyl-2-pentanol 4.29
    propionitrile 10.53
    vinylene carbonate 9.86
    1,1,2-trichlorotrifluoroethane 39.34
    DMS 9.18
    cumene 0.36
    2-octanol 6.05
    2-hexanone 23.21
    octyl acetate 9.33
    limonene 1.64
    1,2-dimethoxyethane 94.15
    ethyl orthosilicate 3.63
    tributyl phosphate 5.33
    diacetone alcohol 56.97
    N,N-dimethylaniline 4.89
    acrylonitrile 18.28
    aniline 6.87
    1,3-propanediol 46.69
    bromobenzene 0.32
    dibromomethane 0.32
    1,1,2,2-tetrachloroethane 3.11
    2-methyl-cyclohexyl acetate 7.16
    tetrabutyl urea 12.98
    diisobutyl methanol 2.58
    2-phenylethanol 11.32
    styrene 0.75
    dioctyl adipate 10.45
    dimethyl sulfate 19.08
    ethyl butyrate 9.25
    methyl lactate 43.89
    butyl lactate 18.52
    diethyl carbonate 4.49
    propanediol butyl ether 47.74
    triethyl orthoformate 7.64
    p-tert-butyltoluene 0.95
    methyl 4-tert-butylbenzoate 16.65
    morpholine 85.09
    tert-butylamine 3.02
    n-dodecanol 4.39
    dimethoxymethane 83.79
    ethylene carbonate 7.68
    cyrene 33.46
    2-ethoxyethyl acetate 23.66
    2-ethylhexyl acetate 4.44
    1,2,4-trichlorobenzene 1.17
    4-methylpyridine 14.24
    dibutyl ether 7.15
    2,6-dimethyl-4-heptanol 2.58
    DEF 49.37
    dimethyl isosorbide 48.42
    tetrachloroethylene 1.25
    eugenol 21.6
    triacetin 19.81
    span 80 27.38
    1,4-butanediol 12.07
    1,1-dichloroethane 0.61
    2-methyl-1-pentanol 6.95
    methyl formate 32.49
    2-methyl-1-butanol 12.32
    n-decane 0.24
    butyronitrile 10.4
    3,7-dimethyl-1-octanol 5.55
    1-chlorooctane 1.37
    1-chlorotetradecane 0.59
    n-nonane 0.16
    undecane 0.19
    tert-butylcyclohexane 0.04
    cyclooctane 0.04
    cyclopentanol 18.08
    tetrahydropyran 22.55
    tert-amyl methyl ether 10.22
    2,5,8-trioxanonane 72.4
    1-hexene 0.27
    2-isopropoxyethanol 37.21
    2,2,2-trifluoroethanol 5.73
    methyl butyrate 18.04

    Scent© AI

1 4

IFRA standard 51

Recommendation
No restriction
Maximum acceptable concentrations in the finished product (%)
Category 1
Products applied to the lips
 No restriction Category 7A
Rinse-off products applied to the hair with some hand contact
 No restriction
Category 2
Products applied to the axillae
 No restriction Category 7B
Leave-on products applied to the hair with some hand contact
 No restriction
Category 3
Products applied to the face/body using fingertips
 No restriction Category 8
Products with significant anogenital exposure
 No restriction
Category 4
Products related to fine fragrance
 No restriction Category 9
Products with body and hand exposure, primarily rinse off
 No restriction
Category 5A
Body lotion products applied to the body using the hands (palms), primarily leave on
 No restriction Category 10A
Household care products with mostly hand contact
 No restriction
Category 5B
Face moisturizer products applied to the face using the hands (palms), primarily leave on
 No restriction Category 10B
Household care products with mostly hand contact, including aerosol/spray products (with potential leave-on skin contact)
 No restriction
Category 5C
Hand cream products applied to the hands using the hands (palms), primarily leave on
 No restriction Category 11A
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate without UV exposure
 No restriction
Category 5D
Baby Creams, baby Oils and baby talc
 No restriction Category 11B
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate with potential UV exposure
 No restriction
Category 6
Products with oral and lip exposure
 No restriction Category 12
Products not intended for direct skin contact, minimal or insignificant transfer to skin
 No restriction