BS 5377-2:1990

National foreword
Committees responsible
Method
Introduction
1. Scope
2. Normative references
3. Selection of specimens and samples from test pieces
4. Determination of intrinsic greying (greying
    measured in the absence of ultraviolet radiation)
5. Determination of intrinsic yellowing (yellowing
    measured in the absence of ultraviolet radiation)
6. Determination of increase in organic deposit content
7. Determination of increase in incineration residue
    (ash)
8. Determination of overall decrease in breaking
    strength (total wear)
9. Determination of decrease in breaking strength
    resulting from chemical degradation of cellulose
    due to laundering (chemical wear)
10. Determination of decrease in breaking strength
    resulting from mechanical factors in laundering
    (mechanical wear)
11. Test report
Annexes
A. Determination of increase (or decrease) in degree
    of whiteness
B. Determination of chemical wear based on variation
    in average degree of viscometric polymerization in
    an ammonium copper (II) hydroxide solution
C. Determination of chemical wear based on variation
    in average degree of viscometric polymerization in
    a copper (II) di(ethylene-diamine)(Cuen) solution
D. Grey scale and measurement of reflection
Tables
C.1 Limiting viscosity number as a function of the
    viscosity ratio increment
D.1 Untitled
Figures
1. Viscometer
2. Supporting tube for viscometer
B.1 Mean degre of viscometric polymerization as a
    function of fluidity value
C.1 Examples of vessels for dissolution of cellulose
C.2 Curve showing the variation in the viscosity ratio
    increment of cellulose solutions in Cuen solution
    as a function of the product of the limiting
    viscosity number and the cellulose concentration
    in the solutions

Methods for determining intrinsic greying and yellowing, increase in organic deposit content and incineration residue, loss of breaking strength, increase or decrease in degree of whiteness, and chemical wear.

This International Standard specifies the methods to be used to determine, under strictly controlled conditions, certain characteristics of unsoiled cotton control cloth, namely intrinsic greying and yellowing, increase in organic deposit content and incineration residue, the overall decrease in breaking strength, the decrease in breaking strength resulting from chemical degradation of the cellulose and the decrease in breaking strength resulting from mechanical factors in laundering both before and after processing, so that certain effects of laundering can be evaluated.

For the purpose of the routine assessment of the affects of processing of cotton textile articles in commercial laundries, the application of some of the methods only may be appropriate. Furthermore, while the methods given in this International Standard evaluate the wear caused by vigorous mechanical action, they do not distinguish between the effects of smaller differences in mechanical action during laundering.