ISO 18948:2025

International
Standard
ISO 18948
Second edition
Imaging materials — Photo books
2025-02
— Test methods for permanence
and durability
Matériaux pour l’image — Albums photos — Méthodes d’essai de
permanence et de durabilité
Reference number
© ISO 2025
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Published in Switzerland
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Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Image permanence tests for covers and pages . 4
4.1 General .4
4.2 Sample preparation .4
4.3 Thermal stability during long-term dark storage .5
4.3.1 General .5
4.3.2 Procedures .5
4.3.3 Reporting .5
4.4 Light stability .5
4.4.1 General .5
4.4.2 Covers .6
4.4.3 Pages .6
4.4.4 Reporting .6
4.5 Ozone stability .6
4.5.1 General .6
4.5.2 Covers .6
4.5.3 Pages .7
4.5.4 Reporting .7
4.6 Humidity stability . .7
4.6.1 General .7
4.6.2 Covers and pages .7
4.6.3 Reporting .7
5 Book integrity tests . 7
5.1 General .7
5.2 Ageing conditions .8
5.3 Page pull test .8
5.3.1 General .8
5.3.2 Test procedure.9
5.3.3 Alternate test procedure .9
5.3.4 Calculation of the binding strength .9
5.4 Peeling and lamination durability . .10
5.4.1 General .10
5.4.2 Resistance to delamination .10
5.4.3 Assessment of age related lamination and binding strength .10
5.4.4 Peeling resistance and lamination bond strength for protective laminate .11
5.4.5 Internal bond strength for glued single side sheets .11
5.4.6 Test sample preparation, results assessment and reporting.11
5.5 Book block attachment to the cover (heat durability) . 12
5.5.1 General . 12
5.5.2 Book binding strength (heat durability) . 12
5.5.3 Opening and closing durability . 12
6 Book blocking .13
6.1 General . 13
6.2 Test conditions . 13
6.3 Test target design .14
6.4 Conditioning of test specimen . 15
6.5 Test methods . 15
6.5.1 General . 15
6.5.2 Equipment and calibration .16

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6.5.3 Test environment control .16
6.5.4 Long term storage (hot/dry) test .17
6.5.5 Long term storage (warm/humid) test .17
6.5.6 Short term transport test .17
6.6 Evaluation .17
6.6.1 General considerations .17
6.6.2 Reporting .17
6.6.3 Additional evaluations .18
7 Deformation caused by humidity . .18
7.1 Page deformation of a photo book (waviness) .18
7.1.1 General .18
7.1.2 Procedure .18
7.1.3 Reporting .19
7.2 Cover deformation of a photo book (warp) . 20
7.2.1 General . 20
7.2.2 Procedure .
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