This standard specifies the test method for measuring the blackness of pigment carbon black with a reflectometer based on the standard reference carbon black 3# (SRB3#). This standard applies to all kinds of pigment carbon black.
GB/T 7048-2003 history
2012GB/T 7048-2012 Colour carbon black.Determination of blackness
2003GB/T 7048-2003 Colour carbon black-Determination of blackness
1993GB/T 7048-1993 Colour black—Determination of blackness