Patents are considered the gold standard for protecting your intellectual property.  Once obtained, they can be used to prohibit others from producing products based on the technology.  They are highly effective and a great tool for building your companies value.  However, they have limitations in that they are expensive, uncertain to be approved, and have limitations on the claims.  A journal entry is an effective defensive tool.  They can prove to another patent holder that their claim is not novel and that your company is not infringing on their intellectual property.  Additionally, they can be used to supplement your patent.  If you have broad claims in your patent, a journal article can be used to effectively document small changes you make over time.