The oil leakage of ballpoint pen is caused by the abrasion of ball and the enlargement of ink outlet, which leads to oil leakage. Saburo Fujinaka, a Japanese, analyzed the structure and failure reasons of ballpoint pens, and also studied the failure of many people to improve the oil leakage problem. Finally, he used the reverse thinking method to successfully prevent the ballpoint pen from leaking oil. Nakata's approach is to make a fuss about the refill. Through repeated experiments, he counted how many words were missed after writing with a ballpoint pen. On the basis of mastering this figure, he began to reduce the oil content of the refill, so that when the bead ring of the ballpoint pen was worn and began to leak oil, the ink in the refill was almost used up, and there was no oil leakage. In this way, nakata skillfully solved the oil spill problem.

If you want to wipe off the leaked oil, you can use detergent.

A good way to avoid oil leakage is to buy a good pen, such as snow/morning light, at a moderate price.