# David K. Donald — Patents explained on PatentBrief

David K. Donald has 1 landmark patent explained in plain English on PatentBrief.

- [How Thermal Inkjet Printers Use Two-Step Heating to Shoot Ink](https://patentbrief.org/patent/us/4490728/thermal-inkjet-printing) — granted 1984
  Hewlett-Packard's 1982 patent on a two-stage electrical pulse method that preheats ink before vaporizing it, allowing thermal inkjet printers to reliably eject precise droplets without clogging.

**Full profile:** https://patentbrief.org/inventor/david-k-donald

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