ISO 2409-2020 pdf free.Paints and varnishes-Cross-cut test.
This document specifies a test method for assessing the resistance of paint coatings and varnishes (including wood stains) to separation from substrates when a right-angle lattice pattern is cut into the coating, penetrating through to the substrate. The property determined by this empirical test procedure depends, among other factors, on the adhesion of the coating to either the preceding coat or the substrate. This procedure is not, however, a means of measuring adhesion.
NOTE 1 Where a measurement of adhesion is required, see the method described in ISO 4624.
NOTE 2 Although the test Is primarily Intended for use in the laboratory, the test Is also suitable for field testing.
The method described can be used either as a pass/fail test or, where circumstances are appropriate, as a six-step classification test. When applied to a multi-coat system, assessment of the resistance to separation of individual layers of the coating from each other can be made.
The test can be carried out on finished objects and/or on specially prepared test specimens.
Although the method is applicable to paint on hard (e.g. metal) and soft (e.g. wood and plaster) substrates, these different substrates need a different test procedure (see Clause 8).
The method is not suitable for coatings of total thickness greater than 250 im or for textured coatings.
NOTE 3 The method, when applied to coatings designed to give a rough patterned surface, will give results
which will show too much variation (see also ISO 16276-2).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1513, Paints and varnishes — Examination and preparation of test samples
ISO 2808, Paints and varnishes — Determination offilm thickness
ISO 4618, Paints and varnishes — Terms and definitions
ISO 13076, Paints and varnishes — Lighting and procedure for visual assessments of coatings
ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
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4 Principle
Six parallel cuts are introduced in the coating and another six cuts are introduced perpendicular to the first cuts. Any loose paint particles are removed. The cut area is examined visually and compared to a six-step classification.
5 Apparatus
5.1 General
Use ordinary laboratory apparatus, together with the apparatus specified in £2 to £4.
5.2 Cutting tool
5.2.1 General requirements
It Is particularly important to ensure that the cutting tool is capable of creating the specified V-shape throughout the total coating thickness, and that the cutting edges are in good condition. Suitable tools are described in £2.2 and 5.2.3 and shown in Figures 1 and 2.
A single-blade cutting tool (51.2) as well as the multi-blade cutting tool (5.2.3) are suitable for all coatings and substrates; it shall be ensured that all cuts mark or scratch the substrate. The depth of indentation into the substrate shall be as low as possible, however.
The tools described in 52 and 5.2.3 are suitable for manual use, which is the more usual method of use, hut the tools may also be mounted on a motor-driven apparatus, which gives more uniform cutting. The application of the latter procedure shall be subject to agreement between the interested parties.
The apparatus (manual or motor-driven) and the type of cutting tool used have an influence on the test result. Results obtained with different types of cutting tool cannot be directly compared. For each test series, the same cutting tool shall be used.ISO 2409 pdf free download.