Stationery Tips

Lead of mechanical pencils

How to make a Spare Leads

The Spare Leads is made through the process of mixing → kneading → extrusion molding → firing → immersion oil → cutting → packaging. It is kneaded by a roll to increase the affinity of the graphite and the resin of the raw material. We perform a preliminary heat treatment and perform firing at about 1200 °c. The oil is permeated for the purpose of imparting thickness and smoothness, and it is completed by cutting it into a constant dimension and putting it in the case.

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