Compound record

Disodium 3,3'-[[1,1'-biphenyl]-4,4'-diylbis(azo)]bis(4-aminonaphthalene-1-sulphonate) (C.I. Direct Red 28)

Also known as Red K

573-58-0 · candidate list substance

SVHC Candidate ListEU monitoring

Dossier

Identity-first dossier for exact-name, CAS, and use-context lookups.

Lookup labels

Red K Congo redDIRECT RED 28C.I. Direct Red 28

Dossier Status Obligations Why Alternatives Changes Similar Sources

CAS 573-58-0

Formula C32H22N6Na2O6S2

Molecular weight 696.7 g/mol

InChIKey IQFVPQOLBLOTPF-UHFFFAOYSA-L

Current EU status

Regulatory snapshot for Disodium 3,3'-[[1,1'-biphenyl]-4,4'-diylbis(azo)]bis(4-aminonaphthalene-1-sulphonate) (C.I. Direct Red 28)

Disodium 3,3'-[[1,1'-biphenyl]-4,4'-diylbis(azo)]bis(4-aminonaphthalene-1-sulphonate) (C.I. Direct Red 28) is currently surfaced as candidate list substance in the EU.

The current imported view anchors this substance in CandidateList. The live rationale focuses on Carcinogenic (Article 57a), and this page is designed for fast status checks before deeper source review.

Searchers usually land here for the chemical name, CAS number, abbreviation Red K, and the question of whether the substance is tied to SVHC, REACH, POPs, or SCIP-style compliance work.

Candidate List substancecurrent statuslatest imported framework state

16 Dec 2013latest anchor datelisted, effective, or checked date

Identity

CAS, formula, aliases, and use context

Fast lookup

CAS 573-58-0 · Formula C32H22N6Na2O6S2 · Molecular weight 696.7 g/mol · Current status Candidate List substance

If you landed here for formula, molecular weight, or exact substance identity, this block gives the shortest route before you branch into status, obligations, or sources.

CAS: 573-58-0
EC: 209-358-4
Formula: C32H22N6Na2O6S2
Molecular weight: 696.7 g/mol
Primary class: candidate list substance
Synonym count: 135

Search-friendly summary

Disodium 3,3'-[[1,1'-biphenyl]-4,4'-diylbis(azo)]bis(4-aminonaphthalene-1-sulphonate) (C.I. Direct Red 28) (Red K) , CAS 573-58-0, is tracked here as a monitored substance in the candidate list substance class.

Common names and aliases

Congo redDIRECT RED 28C.I. Direct Red 28Benzo Congo RedCongazone sodiumHaemomedical

What to do next

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Status

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Obligations

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Why monitored

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Alternatives

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Sources

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Action prompts

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Article duties

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Source check

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