1 Scope and field of application
This standard specifies the method for the quantitative colorimetric evaluation of small colour differences between paint films.
Note: There are numerous formulae for calculating a colour difference from the colour co-ordinates of two specimens. For various reasons the results given by such formulae, including the one defined here, do not in all cases agree satisfactorily with visual perception nor are they likely to agree with each other. The CIE recommended in 1976 two formulae for general use. One of these, the CIE 1976 (L*a*b*) colour difference formula has proved to be of practical value for the colorimetric evaluation of paint films.
2 Normative references
GB 9761 Paints and varnishes - Visual comparison of the colour of paints
GB 11186.1 Methods for measuring the colour of paint films - Part 1: Principles
GB 11186.2 Methods for measuring the colour of paint films - Part 2: Colour measurement
3 Calculation
Foreword II
1 Scope and field of application
2 Normative references
3 Calculation
4 Test report
