GB/T 31479-2015Determination of colour fastness of dyed paper and board intended to come into contact with foodstuffs (English PDF)

Foreword

This Standard was drafted as per the rules specified in GB/T 1.1-2009.

1 Scope

This Standard specifies the two methods for determination of colour fastness of dyed paper and board intended to come into contact with foodstuffs.

Method A in this Standard is applicable to the determination of colour fastness of dyed paper and board (such as food packaging paper) intended to come into long-term contact (contact time>=24h) with foodstuffs; while Method B is applicable to the determination of colour fastness of dyed paper and board (such as napkins, and kitchen paper) intended to come into short-term contact (contact time < 24h) with foodstuffs.

2 Normative References

The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) are applicable to this document.

GB/T 251 Textiles - Tests for Colour Fastness - Grey Scale for Assessing Staining

GB/T 450 Paper and Board - Sampling for Testing and Identification of Machine and Cross Direction Wire Side and Felt Side

GB/T 461.1 Paper and Board - Determinatoin of Capillary Rise (Klemm Method)

3 Principle

Contact the specimen and tested solution with the glass fiber paper completely immersed for 10 min; place them for a certain period under certain pressure; compare the stained glass fiber paper (test sample) with the blank sample, and use the gray scale to assess the grade. Select the test solution as per the paper usage; the test solution contains distilled water or deionizer water, dilute acetic acid, saliva simulant, isooctane or olive oi.

NOTE: in this Standard, the specimen indicates the tested dyed paper or board. Blank sample […]