To Next Page

To Previous Page

CHAPTER 2 – Measurement functions

OBA amount no OBA faint low moderate high

∆B 0 to 1 1 to 4 4 to 8 8 to 14 14 to 25*

∆CIEb* 0 -0,3 to -2,0 -2,0 to -3,7 -3,7 to -6,2 -6,2 to -10,4*

OBA-Check

Optical Brightening Agents (= OBAs) which are used more and more in the paper pro-

duction, have a signicant eect not only on how we perceive the paper under dif-

ferent illuminants, but also on the results of the printing process. The measurement

function OBA-Check provides precise information about the intensity of the optical

brightening agents used and the shade of the paper.

Choose the function OBA-Check from the

menu measurement functions.

First you have to switch to the „soft-key“ CAL

to carry out a calibration on the absolute

white standard.

SpectroDens performs the OBA-Check ap-

plying the measurement conditions M1 and

M2, i. e. with and without stimulation through

UV light (see p. 50). The dierence between

the two CIEb*-values leads to the nal mea-

surement result.

The amount of optical brightening agents

according to ∆B (ISO 15397) and its categori-

zation according to ISO 12647-2:





(0 ≤ ∆B < 1) no OBA





(0 ≤ ∆B < 4) OBA faint





(4 ≤ ∆B < 8) OBA low





(8 ≤ ∆B < 14) OBA moderate





(14 ≤ ∆B < 25*) OBA high

The table shows the relation between ∆B-

and CIEb*-values for the practical application.

* and beyond

Techkon SpectroDens User Manual

Questions and Answers: