# Kazumasa Yokoyama — Patents explained on PatentBrief

Kazumasa Yokoyama has 1 landmark patent explained in plain English on PatentBrief.

- [How to Make Hard-to-Absorb Medicines Easier for the Body to Use](https://patentbrief.org/patent/us/5002952/duragesic-fentanyl-patch) — granted 1991
  A method for mixing specific chemical compounds with surfactants to help the body absorb them more effectively.

**Full profile:** https://patentbrief.org/inventor/kazumasa-yokoyama

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_Source: PatentBrief — https://patentbrief.org. Plain-English explanations of US patents._