C.I. Acid Red 1

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  • Identifiers

    CAS number
    3734-67-6

    Molecular formula
    C18H13N3Na2O8S2

    SMILES
    CC(=O)NC1=C2C(=CC(=C1)S(=O)(=O)[O-])C=C(C(=C2O)N=NC3=CC=CC=C3)S(=O)(=O)[O-].[Na+].[Na+]

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  • Odor profile

    Fragrance
    Odorless 77.93%
    Cooked 24.91%
    Savory 23.57%
    Bitter 19.57%
    Grape 18.74%
    Fruity 17.64%
    Roasted 17.4%
    Meaty 17.37%
    Burnt 16.86%
    Milky 15.02%

     

    Flavor
    Bitter 86.24%
    Odorless 38.26%
    Bland 22.51%
    Nitrile 20.64%
    Mild 19.26%
    Bread crust 18.91%
    Taco 18.88%
    Roasted peanuts 18.71%
    Very strong 18.41%
    Sweet-like 18.19%

     

    Odor impact est.
    Odorless

  • Properties

    pKa est.
    3.58 (weak acid)

    Molecular weight
    509.4 g/mol

    Flash point

    • 318.42 ˚C est.

  • Synonyms

    • 3734-67-6
    • Red 2G
    • C.I. Acid Red 1
    • Lissamine Red 2G
    • C. I. Food Red 10
    • 1379 Red
    • CI 18050
    • DTXSID9044663
    • 3365R6427R
    • DTXCID7024663
    • azofloxin
    • RefChem:572118
    • Acid red 1
    • Azophloxine
    • Acid Red 2G
    • Amido Naphthol Red G
    • Amidonaphthol Red
    • Azophloxin
    • C.I. Acid Red 1, disodium salt
    • Azo Phloxine
    • Phloxine G
    • Acid Bright Red
    • Acidine Red G
    • Azo Phloxine GA
    • Fast Crimson GR
    • Fast Drimson GR
    • Leather Red G
    • Acetyl Red G
    • Acetyl Red J
    • Egacid Red G
    • Fenazo Red B
    • Geranine 2GS
    • Phloxine 2G
    • Acid Phloxine GA
    • Azo Geranine 2G
    • Erio Floxine 2G
    • Amacid Phloxine G
    • Azonaphthol Red J
    • Kiton Red G
    • Acetyl Rose 2GL
    • Azo Rhodine 2G
    • Hexacol Red 2G
    • Hexalan Red 2G
    • Acid Brilliant Red
    • Acid Red GA
    • Azo Geranine 2GA
    • Belacid Phloxine G
    • Erio Floxine 2GN
    • Kiton Fast Red G
    • Amido Red 2G
    • Kiton Red 2G
    • Naphtocard Red 2G
    • Acid Naftol Red G
    • Acid Rose 2GL
    • Ink Red JSN
    • Ahcocid Carmine 2G
    • Acid Fast Red 3G
    • Bucacid Fast Crimson
    • Hidacid Fast Crimson
    • Java Naphtol Red G
    • Acid Fast Red EGG
    • Cetil Light Red GG
    • Hastings Carmine 2G
    • Naphthazine Rose 2G
    • Pontacyl Carmine 2G
    • Solar Fast Red 3G
    • Unitertracid Red 2G
    • Azo Phloxine GA-CF
    • Calcocid Phloxine 2G
    • Acid Leather Red KG
    • Acilan Naphtol Red G
    • Atul Acid Geranine G
    • Brilliant Acid Red G
    • Acilan Naphthol Red G
    • Amido Naphthol Red GA
    • Eniacid Light Red 3G
    • Vondacid Light Red NG
    • Amido Naphthol Red 2G
    • Brilliant Colacid Red G
    • Acidal Brilliant Red 2G
    • C.I. Food Red 10
    • Edicol Supra Geranine 2G
    • Edicol Supra Geranine 2GS
    • Hispacid Fast Carmoisine G
    • Brilliant Acid Rosamine 2G
    • C.I. 18050
    • Edicol Supra Geranine 2 GS
    • Ext D and C Red No. 11
    • Disodium 5-acetylamino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate
    • Sodium 5-acetamido-4-hydroxy-3-(phenyldiazenyl)naphthalene-2,7-disulfonate
    • 2,7-Naphthalenedisulfonic acid, 5-(acetylamino)-4-hydroxy-3-(phenylazo)-, disodium salt
    • 2,7-Naphthalenedisulfonic acid,5-(acetylamino)-4-hydroxy-3-(phenylazo)-, disodium salt
    • Amacid Phloxine
    • disodium;5-acetamido-4-hydroxy-3-phenyldiazenylnaphthalene-2,7-disulfonate
    • Ariavit Red 2G
    • Acid Red 1 (Technical Grade)
    • Cerven 2G [Czech]
    • Cerven kysela 1 [Czech]
    • disodium 5-acetamido-4-hydroxy-3-(phenyldiazenyl)naphthalene-2,7-disulfonate
    • Cerven kysela 1
    • Cerven 2G
    • 2,7-Naphthalenedisulfonic acid, 5-(acetylamino)-4-hydroxy-3-(2-phenyldiazenyl)-, sodium salt (1:2)
    • NSC-8666
    • MFCD00003954
    • NSC-47709
    • Cerven potravinarska 10 [Czech]
    • Cerven potravinarska 10
    • NSC 8666
    • EINECS 223-098-9
    • NSC 47709
    • AMIDONAPHTHOL RED G
    • Acid Red 2G (E128)
    • Pontacyl Carmine
    • (EZ)-azophloxine
    • UNII-3365R6427R
    • AZOGERANINE
    • Food Red 10
    • CI ACID RED 1
    • FABRACID RED S 2G
    • CI FOOD RED 10
    • Dye content 90-100%
    • Acid Red 2G (E128) 100 microg/mL in Water
    • Red 2G, analytical standard
    • SCHEMBL340610
    • Acid Red 2G (E 128)
    • INS NO.128
    • SCHEMBL2121238
    • 3734-67-6

  • Applications

    C.I. Acid Red 1 is an azo dye primarily used as an acid dye for protein fibers (wool and silk) and for certain polyamide fibers (nylon) under acidic conditions to impart a red shade. It is also employed for leather dyeing and can serve as a colorant in printing inks and coating formulations related to the textile sector. As an azo dye intermediate, it is commonly used as a precursor for the synthesis of other azo dyes. In industrial manufacturing, it may be used as a colorant in inks, coatings, or plastics, subject to local regulations and formulation limits.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 5.56
    methanol 5.99
    isopropanol 1.96
    water 0.02
    ethyl acetate 6.47
    n-propanol 3.17
    acetone 25.8
    n-butanol 1.69
    acetonitrile 8.86
    DMF 71.35
    toluene 0.75
    isobutanol 1.27
    1,4-dioxane 18.73
    methyl acetate 11.64
    THF 52.52
    2-butanone 19.93
    n-pentanol 1.03
    sec-butanol 1.93
    n-hexane 0.01
    ethylene glycol 1.93
    NMP 67.47
    cyclohexane 0.05
    DMSO 74.02
    n-butyl acetate 3.93
    n-octanol 0.98
    chloroform 2.87
    n-propyl acetate 4.77
    acetic acid 12.15
    dichloromethane 4.59
    cyclohexanone 21.11
    propylene glycol 2.03
    isopropyl acetate 2.83
    DMAc 82.15
    2-ethoxyethanol 11.51
    isopentanol 0.91
    n-heptane 0.02
    ethyl formate 8.22
    1,2-dichloroethane 3.64
    n-hexanol 0.67
    2-methoxyethanol 34.01
    isobutyl acetate 1.31
    tetrachloromethane 0.13
    n-pentyl acetate 2.72
    transcutol 16.75
    n-heptanol 0.81
    ethylbenzene 0.23
    MIBK 2.05
    2-propoxyethanol 10.82
    tert-butanol 1.21
    MTBE 0.86
    2-butoxyethanol 6.4
    propionic acid 5.26
    o-xylene 0.38
    formic acid 9.86
    diethyl ether 1.97
    m-xylene 0.23
    p-xylene 0.38
    chlorobenzene 1.01
    dimethyl carbonate 6.78
    n-octane 0.01
    formamide 22.52
    cyclopentanone 41.81
    2-pentanone 7.18
    anisole 2.32
    cyclopentyl methyl ether 3.0
    gamma-butyrolactone 41.7
    1-methoxy-2-propanol 13.77
    pyridine 18.81
    3-pentanone 5.29
    furfural 29.64
    n-dodecane 0.02
    diethylene glycol 8.83
    diisopropyl ether 0.16
    tert-amyl alcohol 1.26
    acetylacetone 15.24
    n-hexadecane 0.03
    acetophenone 4.72
    methyl propionate 8.42
    isopentyl acetate 2.25
    trichloroethylene 7.75
    n-nonanol 1.08
    cyclohexanol 1.26
    benzyl alcohol 2.52
    2-ethylhexanol 0.41
    isooctanol 0.49
    dipropyl ether 1.1
    1,2-dichlorobenzene 0.83
    ethyl lactate 3.35
    propylene carbonate 10.01
    n-methylformamide 24.57
    2-pentanol 0.63
    n-pentane 0.02
    1-propoxy-2-propanol 5.77
    1-methoxy-2-propyl acetate 6.25
    2-(2-methoxypropoxy) propanol 7.88
    mesitylene 0.1
    ε-caprolactone 16.31
    p-cymene 0.24
    epichlorohydrin 31.17
    1,1,1-trichloroethane 1.05
    2-aminoethanol 3.38
    morpholine-4-carbaldehyde 51.96
    sulfolane 50.04
    2,2,4-trimethylpentane 0.01
    2-methyltetrahydrofuran 10.24
    n-hexyl acetate 3.02
    isooctane 0.0
    2-(2-butoxyethoxy)ethanol 9.84
    sec-butyl acetate 1.69
    tert-butyl acetate 2.32
    decalin 0.01
    glycerin 5.64
    diglyme 20.04
    acrylic acid 6.66
    isopropyl myristate 1.33
    n-butyric acid 4.77
    acetyl acetate 4.36
    di(2-ethylhexyl) phthalate 2.14
    ethyl propionate 3.82
    nitromethane 41.88
    1,2-diethoxyethane 4.79
    benzonitrile 3.74
    trioctyl phosphate 1.32
    1-bromopropane 0.88
    gamma-valerolactone 70.97
    n-decanol 0.81
    triethyl phosphate 1.63
    4-methyl-2-pentanol 0.25
    propionitrile 4.81
    vinylene carbonate 9.37
    1,1,2-trichlorotrifluoroethane 15.87
    DMS 4.15
    cumene 0.12
    2-octanol 0.51
    2-hexanone 5.36
    octyl acetate 2.25
    limonene 0.3
    1,2-dimethoxyethane 24.58
    ethyl orthosilicate 1.25
    tributyl phosphate 1.6
    diacetone alcohol 5.59
    N,N-dimethylaniline 1.16
    acrylonitrile 9.75
    aniline 2.17
    1,3-propanediol 5.84
    bromobenzene 0.63
    dibromomethane 1.84
    1,1,2,2-tetrachloroethane 5.08
    2-methyl-cyclohexyl acetate 2.41
    tetrabutyl urea 4.1
    diisobutyl methanol 0.21
    2-phenylethanol 2.39
    styrene 0.37
    dioctyl adipate 3.19
    dimethyl sulfate 10.77
    ethyl butyrate 3.52
    methyl lactate 7.79
    butyl lactate 3.16
    diethyl carbonate 2.51
    propanediol butyl ether 4.53
    triethyl orthoformate 2.45
    p-tert-butyltoluene 0.2
    methyl 4-tert-butylbenzoate 4.02
    morpholine 23.41
    tert-butylamine 0.32
    n-dodecanol 0.56
    dimethoxymethane 24.38
    ethylene carbonate 7.1
    cyrene 9.84
    2-ethoxyethyl acetate 6.54
    2-ethylhexyl acetate 1.66
    1,2,4-trichlorobenzene 1.75
    4-methylpyridine 9.0
    dibutyl ether 1.07
    2,6-dimethyl-4-heptanol 0.21
    DEF 11.35
    dimethyl isosorbide 13.57
    tetrachloroethylene 2.16
    eugenol 5.16
    triacetin 4.64
    span 80 4.52
    1,4-butanediol 1.43
    1,1-dichloroethane 1.67
    2-methyl-1-pentanol 0.64
    methyl formate 21.37
    2-methyl-1-butanol 1.07
    n-decane 0.04
    butyronitrile 3.31
    3,7-dimethyl-1-octanol 0.56
    1-chlorooctane 0.29
    1-chlorotetradecane 0.14
    n-nonane 0.03
    undecane 0.03
    tert-butylcyclohexane 0.01
    cyclooctane 0.01
    cyclopentanol 3.14
    tetrahydropyran 7.38
    tert-amyl methyl ether 0.9
    2,5,8-trioxanonane 16.12
    1-hexene 0.11
    2-isopropoxyethanol 4.61
    2,2,2-trifluoroethanol 4.07
    methyl butyrate 6.24

    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