;CONSTITUTION: An invisible ink contains, for example, pigment and a microcyanine color-fading coloring agent. The color-fading coloring agent is bluish but is discharged by emission of infrared beam. This chemical reaction is irreversible. Consequently, first, a bar code is printed using an ...
If the ink uses a particular chemical compound, you may need to use acid. It will turn the ink into a different color visible to naked eyes because of a chemical reaction. Furthermore, you can also use UV light because some inks will reflect a specific wavelength. 3. Secret Communication ...
This chemical reaction is irreversible. Consequently, first, a bar code is printed using an invisible ink containing a color-fading coloring agent (step S03), then a blue bar code is verified (steps S04, S05) and the color is deprived by emission of infrared beam (step S06) to obtain ...
Make and Use the Ink Mix equal parts water and baking soda. Use a cotton swab, toothpick, or paintbrush to write a message onto white paper, using the baking soda solution as "ink." Allow the ink to dry. One way to read the message is to hold the paper up to a heat source, such...
For application as a secu- rity ink, the components of that ink must be invisible under visible light as well as UV light. The printed mate- rial should not be photocopied and the code is readable under certain special conditions26. Highly luminescent Department of Chemical Sciences, Indian ...
If you don’t have lemon juice, you can create invisible ink with equal amounts of baking soda and water. The same reaction happens when it comes into contact with heat. You can also hold it up to a light and see the invisible ink. ...
(1) Ink writing involves 3D printing with a colloidal suspension [9], or photonic precursors [10], as well as 2D patterning with a colloidal suspension [11], or solvents/salts/reactive monomers [12–15]. (2) Photomasking controls the degree of the reaction or crosslinking in ultraviolet ...