Many people who like calligraphy will add vinegar to the ink when they write. This is because ink contains alkaline components. Adding vinegar to ink will produce a chemical reaction, which will make the written words darker and more shiny, and the handwriting can be preserved for a longer time.
Matters needing attention in writing with ink and vinegar
Although it is good to write with ink and vinegar, it must be noted that it is best not to pour the vinegar-added ink back into the bottle after use. The composition of vinegar-added ink has changed and it is very easy to deteriorate. If you pour it back into the bottle, it will lead to all the ink deterioration and waste.