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

Red K SVHC Candidate ListEU monitoring 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

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

Use the right route for status, SCIP, and source questions

Status

Current legal state, Candidate List signals, and source-backed rationale

Go here for the framework answer block, listed dates, reasons, and the imported basis for the current EU status.

Obligations

Who needs to act, what to check, and whether SCIP matters

Use this when the question is operational: SCIP, article communication, threshold review, portfolio screening, or substitute work.

Why monitored

Why this substance is monitored in the EU

Use this when you want the hazard or legal basis behind the current status, not just the status label itself.

Alternatives

Potential substitutes and nearby molecules

Use this to branch into lower-pressure neighbors, same-class analogs, and candidate-list peers.

Changes

What changed over time

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Sources

Verify where the data came from

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Action prompts

Fast compliance and screening routes

Article duties

Check Candidate List threshold and SCIP relevance

Use this when the substance may sit in articles, components, or imported goods and you need to confirm communication and SCIP workflows.

Source check

Verify the legal source before repeating the claim

Every summary should point back to the underlying authority surface. Use the source route when the exact notice, registry entry, or legal text matters.