ISO 20492-4:2010 pdf free download – Glass in buildings一Insulating glass一 Part 4: Methods of test for the physical attributes of edge seals.
D.1 General
Insulating glass units with a coating in the cavity shall not be sealed on the coating, unless the coated glass is accompanied by information from the coated-glass supplier that sealing on the concerned coating is allowed. That information for coated glasses as defined in D.2 shall be collected as described D.3 to D.6.
When no sealing is allowed on the coating, the coated glass shall be accompanied by information from the coated-glass supplier on how the coating can be stripped. These types of coatings are not considered further in this annex.
D.2 Concerned coatings
The concerned coatings, which have been declared as “not necessary to be stripped”, shall be in accordance with EN 1096 (all parts).
D.3 Composition of coatings
The coating manufacturer shall establish a list of combinations of coatings with a given sealant (public part of the list) and their composition in layers (confidential part of the list).
The layers may be listed by the full-name composition or by a manufacturer’s code. Additional coatings may be added to this list when evaluated according to this part of ISO 20492.
D.4 Evaluation
D.4.1 General
For each of those coatings, it shall be demonstrated that the adhesion between glass and coating, between sealant and coating, and between the different layers of the coating is sufficiently strong. Demonstration shall be performed by testing, or by available previous test reports, or by a combination of testing and available previous test reports.
D.4.2 Evaluation by testing
The flow chart in Figure D.1 shall be followed; however step 3 may be omitted. The test report shall include a section made in accordance with this annex.
The test specimens in step 3 shall be made with a reference sealant. That reference sealant shall be a neutral one and strong enough to test cohesion and adhesion strength. It can be a neutral silicone sealant.
In step 5, it shall be taken into account that the internal strength of the coating is already satisfactorily investigated so that testing can be limited to only the top layer/sealant adhesion.
The test report shall include a section in accordance with Clause 6.
— test specimens with any same adjacent layer combination in the coating as for the coating being evaluated.
D.4.4 Evaluation by a combination of testing and previous test reports
Where the previous test reports do not cover specified layer combinations or the specified top layer of the coating to be evaluated,
— the test specimens shall be sealed on coated glass containing the specified layer combination, or specified top layer/sealant combination; or
— the test specimens shall be sealed with the concerned coating/sealant combination, for submitting to the test procedures of Clause 5 and for reporting in accordance with this annex.
D.5 Example
D.5.1 Requested for coated glasses from one manufacturer:
— coating I submitted for evaluation of suitability: [glass] – [layer 1-layer 2] – [sealant A];
— coating II submitted for evaluation of suitability: [glass] – [layer 2-layer 1] – [sealant A].
D.5.2 Available test reports in accordance with ISO 20492-1 or in accordance with this annex on coated glasses from the same coated glass supplier:
— adhesion report 1: [glass] – [layer 1-layer 2-layer 3] – [sealant B]; accepted;
— adhesion report 2: [glass] – [layer 2] – [sealant A]; accepted.
D.5.3 It may be concluded that
— coating lis accepted because
1) glass – layer 1 is accepted (report 1),
2) layer 1 – layer 2 is accepted (report 1),
3) layer 2 – sealant A is accepted (report 2),
— coating II is acceptable after testing of a coating in which appears the combination “layer 1 – sealant A”, because
1) glass – layer 2 is accepted (report 2),
2) layer 2 – layer 1 is accepted (report 1),
3) layer 1 – sealant A was not tested.