METHOD OF MARKING COMPOSITION FOR ORAL ADMINISTRATION

摘要

It is intended to provide a marking method by which a highly distinguishable composition for oral administration (for example, a drug or a food) can be obtained without worsening the qualities of the composition for oral administration and which has a high productivity. Namely, a method of marking a composition for oral administration which comprises the step of dispersing a color change-inducing oxide in the composition for oral administration and the step of scanning the surface of the composition for oral administration with a laser beam of from 200 nm to 1100 nm in wavelength and from 0.1 W to 50 W in average output to thereby aggregate particles of the color change-inducing oxide and induce the color change. The color change-inducing oxide to be used herein is at least one member selected from the group consisting of titanium oxide, yellow iron sesquioxide and iron sesquioxide.