ISO 22553-8-2020 Paints and varnishes – electrodeposition coatings – Part 8: Charge density

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ISO 22553-8-2020 Paints and varnishes – electrodeposition coatings – Part 8: Charge density

The charge density provides information about the efficiency of the deposition process during the electrodeposition coating process.

If you need to measure wet film resistance according to ISO 22553-7, you can specify it in the test kit provided.

1 Scope of application
This document specifies a method for determining the charge density of electrodeposited coatings (e-coat) for the automotive industry and other general industrial applications (e.g. water chillers, consumer goods, radiators, aerospace, agriculture).

2 Normative reference files
When the following documents are referenced in the context, part or all of them constitute the requirements of this document. For dated references, citation-only versions apply. For undated citations, the most recent version of the referenced document (including any amendments) applies.

ISO 1514, Paints and varnishes — Standard plates for testing

ISO 2808, paints and varnishes – determination of film thickness

ISO 4618, Paints and varnishes – Terms and definitions

ISO 22553-1, Paints and varnishes – electrodeposited coatings – Part 1: Vocabulary

ISO 23321, Paints and varnishes solvents – softening water for industrial applications – Specification and test methods

3 Terms and Definitions
For the purposes of this document, the terms and definitions given in ISO 4618, ISO 22553-1 and below apply.

3.1 Charge density

Volume charge ρ _

Quotient of charge Q and volume V:


Note 1: Charge density is expressed as coulomb per cubic meter (C… m −3).

Entry note 2:1 C⋅m −3 = 1 A⋅s⋅m −3.

3.2 Practical dry film density

Actually determine the density of drying and curing coatings

[Source: ISO 3233-3:2015, 3.4, Modified: A hyphen has been added to the term between “dry” and “film”.]

3.3 Theoretical dry film density

The coating density is calculated by the solvent, the coating material density and the non-volatile substance content of the coating material

[Source: ISO 3233-3:2015, 3.6, Modified: A hyphen has been added to the term between “dry” and “film”.]

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