Fabrication of Robust Spatially Resolved Photochromic Patterns on Cellulose Papers by Covalent Printing for Anticounterfeiting Applications was written by Bretel, Guillaume;Le Grognec, Erwan;Jacquemin, Denis;Hirose, Takashi;Matsuda, Kenji;Felpin, Francois-Xavier. And the article was included in ACS Applied Polymer Materials in 2019.Safety of 3-Bromo-2-methylbenzo[b]thiophene This article mentions the following:
Despite its millennial age, cellulose paper remains the preferred material for domestic and professional printings, covering applications from simple office paperwork to fiducial solutions such as bills, passports, and head letters. The creation of robust photochromic patterns on cellulose papers for anticounterfeiting applications is an important and still partially unaddressed challenge. In this contribution, we report the covalent printing of dibenzothienylethenes as photochromic compounds through a spatially controlled light-mediated thiol-X ligations. Photophys. and theor. studies provide evidence for a reversible photochromism behavior, not affected significantly by the polar environment of the cellulose matrix, and demonstrates a high fatigue resistance over 18 successive write-erase cycles. The strong coloration-discoloration switch can be easily followed by a direct naked-eye readout. In the experiment, the researchers used many compounds, for example, 3-Bromo-2-methylbenzo[b]thiophene (cas: 10243-15-9Safety of 3-Bromo-2-methylbenzo[b]thiophene).
3-Bromo-2-methylbenzo[b]thiophene (cas: 10243-15-9) belongs to benzothiophene derivatives. Functionalized benzothiophenes are important constructs found in molecules with wide ranging biological activity and in organic materials. It has been used as a raw material for the synthesis of biologically active structures and is found in pharmaceuticals such as leukotriene synthesis inhibitors and antifungals, as well as in many natural products.Safety of 3-Bromo-2-methylbenzo[b]thiophene
Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem