本文件规定了在室外日光条件下用仪器测定纸巾和纸巾制品亮度和颜色的试验程序。它还提供了试样制备（单层、多层产品）和产品光学测量的具体说明，其中可能需要采取特殊预防措施。 注？使用比本文件规定的紫外线含量低得多的仪器测量称为ISO亮度和颜色（C/2°（室内日光）的特性。ISO 12625-15中描述了用C/2°测量ISO亮度和颜色（室内日光）。

This document specifies testing procedures for the instrumental determination of brightness and colour of tissue paper and tissue products viewed under outdoor daylight conditions. It also gives specific instructions for the preparation of test pieces (single-ply, multi-ply products) and for the optical measurements of products, where special precautions can be necessary. NOTE？The properties called ISO brightness and colour with C/2° (indoor daylight) are measured with an instrument adjusted to a much lower UV content than that specified in this document. The measurements of ISO brightness and colour with C/2° (indoor daylight) are described in ISO 12625-15.