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CAS 2 records

CAS 3520-42-1

CAS 3520-42-1 matches 2 EU annex records across Annex II–VI of Regulation 1223/2009.

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Records for CAS 3520-42-1

2 total
Annex
III
Entry
193

ACID RED 52

Hydrogen 3,6-bis(diethylamino)-9-(2,4-disulphonatophenyl)xanthylium, sodium salt; CI 45100 (see note 17)

a) To be printed on the label: The mixing ratio. “ Hair colourants can cause severe allergic reactions. Read and follow instructions. This product is not intended for use on persons under the age of 16. Temporary ‘black…

EC
222-529-8
Max concentration

How CAS 3520-42-1 is used on this site

CAS 3520-42-1 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 2 EU annex records share this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 3520-42-1 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.

Frequently asked questions

A substance identified by CAS 3520-42-1 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts. For example, a substance might be restricted under Annex III with specific conditions, and the same CAS might also appear in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

Cross-reference the CAS number against your raw material specification sheets and CoA documents. When a CAS appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met in your formulation. All annex entries sharing this CAS number are listed above.

A CAS number is assigned by the Chemical Abstracts Service (USA) and is globally recognised. An EC number is a European Commission identifier from inventories such as EINECS, ELINCS or the NLP list. Both identifiers may appear in EU cosmetic annex entries. Some substances have both, some have only one, and some older entries may have neither.

Use the INCI Checker to scan your full ingredient list against all EU annex entries. The checker matches by INCI name. For CAS-based matching, verify against raw material specification sheets and compare CAS numbers with the entries listed on this page.
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