Regarding Kitamura-San's questions, we would comment as belows:
When gringing work rolls, stone is used (not abrasive belt). Therefore, we find possibility that Al2O3 comes from work roll grinding process is little. After grinding, the rolls are cleaned by grinding coolant.
Regarding mesh of rolling oil filter, we believe it is not the source of Al2O3 as it was easily removed by in-house washing process. If it comes from rolling oil, it won't be easily cleaned as it tends to be embedded dirung rolling and annealing process as its' atmosphere is over 1000 Celsius.
Lastly, there is no any polishing process to make the material.
I hope it answers to him. Let us try to elaborate it during the meeting on Monday. Before the meeting, can we check what kind of physical method and solutions are used for the in-house washing process?