Dear pak Yo n IBN Thai team,
The reason why we ask you to prepare samples of 2% colorant +/- 0.1% is because we'd like to bring the usage back to original percentage.
I remember there was a discussion about this percentage differences last year and I asked to adjust the colorant concentation at supplier side so we can keep using 2% as per original BOM, but we can't make it. I think this is a good time to make it happen and save the 10% cost of colorant. Agree?
Regarding the tolerance, we found that in this case +/- 0,2% seems too wide. We afraid we can't accept 1.8% as lower tolerance when we decided 2% as the middle range. That's why we propose to make a narrower range of +/- 0.1%... 1,9% 2.0% 2.1%
Hopefully with this narrower range, the color still acceptable, not too light.
Beside the color effect, this narrower range also help in cost reduction.
But of course we need extra control and coordination since we push it to the limit.
Please prepare the sample as requested using the commercial colorant, not the samples, so we can get better uniformity.
While waiting for the trial, you may use 2.2% +/-0.2% of the new colorant from polyone and also clariant as per below approval.