DIN EN ISO 12625-16:2015-05

This document has been prepared by CEN/TC 172 "Pulp, paper and board", the secretariat of which is held by the Standards Committee Paper, board and pulps (NPa) at DIN. The decision-making committee within CEN/TC 172 is WG 8 "Specification for test methods for soft tissue paper", which is chaired by Germany. Representatives of the Standards Committee "Paper, board and pulps" participated in the preparation of this European Standard. The national mirror committee here is NA 074-02-05 AA "Prüfverfahren für Tissue-Papier und Tissue-Produkte" ("Test methods for tissue paper and tissue products"). This part of ISO 12625 specifies testing procedures for the instrumental determination of opacity paper backing of tissue paper and tissue products by diffuse reflectance. This part of ISO 12625 also gives specific instructions for the preparation of test pieces (single-ply, multi-ply products), where special precautions may be necessary. It can be used to determine the opacity of tissue paper and tissue products which contain fluorescent whitening agents, provided the UV content of the radiation incident on the test piece has been adjusted to conform to that in the CIE illuminant C using a fluorescent reference standard provided by an ISO/TC 6 authorized laboratory as described in ISO 2470-1. This part of ISO 12625 is not applicable to coloured tissue paper and tissue products which incorporate fluorescent dyes or pigments.