According to point 3 of Article 3 of the REACH Regulation, an “article” means “an object which during production is given a special shape, surface or design which determines its function to a greater degree than does its chemical composition”.
To determine whether the product meets the definition of an article according to REACH, the product’s function and its shape, surface or structure must be examined.
The product’s shape, surface and structure must not be confused with physical characteristics that are the result of the chemical properties of the material(s) used in the manufacture of the product. Examples of these properties or characteristics of the material include propensity to split, density, flexibility, electrical conductivity, hardness, magnetism and melting point.
If the product is a combination of a substance/mixture and an article (the substance or mixture is delivered in a vessel or carrier), a chemical notification must be made regarding the substance/mixture included in the product as necessary (such as detergent contained in a cleaning wipe, a candle, or ink contained in a printer cartridge).
However, if the product is considered an article to which the substance/mixture belongs integrally (the substance/mixture is a fixed part of the article), a chemical notification is not required (e.g., battery acid contained in a car battery).
See also ECHA’s guidance on REACH (Guidance on requirements for substances in articles).