Lubricant sheet for making holes and method of making holes with drill

摘要

A lubricant sheet suitable for use in a process of making a hole in a printed circuit board, which sheet comprises a water-soluble polymer layer, which has a thickness of 0.02 to 3.0 mm, and a metal foil having a thickness of 0.05 to 0.5 mm,
said water-soluble polymer layer being formed on one surface of said metal foil, wherein said metal foil is an aluminum foil having an aluminum purity of at least 99.5%.