Pigment Synthesis and Analysis of Color in Art: An Example of Applied Science for High School and College Chemistry Students

摘要

We present herein a module of pigment synthesis experiments that could be adapted and implemented in a variety of curricular settings. At the conclusion of each of the past two spring terms at our high school, we offered a 4 day short course on the chemical synthesis of pigments used in art. As part of the course, our students synthesized four pigments in the chemistry laboratory: Egyptian blue, madder lake (red), cobalt green, and cobalt yellow. These particular pigments were selected for several reasons: (1) they are historically significant in art and archeology (their usage spans from antiquity into the 20th century), (2) they provide for a variety in the chemical reaction types explored and the chemical synthesis methods utilized, (3) they are relatively safe for students to handle, and (4) they afford a diverse color palette upon mixing. Our students then combined their pigments with gum arabic as a binder to make gouache watercolor paints and create a painting. In the second iteration of the short course, students also collected gravimetric data during their pigment synthesis reactions and were introduced to photoluminescence imaging of paints made from Egyptian blue and madder lake pigments synthesized the prior year. We also explored the quantitative colorimetry of the paints via fiber-optic reflectance spectroscopy. On the basis of positive student feedback from our short course and on our research into similar curricular offerings at the college and university level, we are actively working to expand and broaden the material into a new, year-long, interdisciplinary elective course for our upper-level high school students that describes the application of chemistry and materials science principles to enhance our understanding and appreciation of art and archeology.