The role of ink today can not be separated from everyday human life from art, journalism, to the printing industry, all in need of ink, although at first seem trivial (Williams, 1988). Inks began to be used by people from the 3rd to 4th centuries AD by the Romans during the use of pen aids for writing. By the middle of 1700, most ink-making was done by the wearer himself, for example Alois Senefelder, the inventor of lithography, producing ink for his own purposes of printing. This seems to spur chemists to compete in the early 19th century ink development. The rheological study, a branch of the fluid science of materials, has contributed greatly to the development of the ink industry.
The manufacture of commercial inks did not appear until the early 1900s, when ink manufacturing was not a science but an art that was produced by the best formula by the manufacturer, so that certain formulas became something very secret for others. It is a fact that ink on the one hand is an integral part of graphic arts, so the development of ink technology is also in line with the development of paper technology, printing systems and materials makers. One of the basic ingredients used as a dye or is a tannin, tannin is a chemical compound that exists in wood and leaves from plants, one of the plants that contain lots of tannins in the leaf on a tea plant.
Tea is a beverage made from tea plant leaves in the Latin language Camellis sinensis. Tea plants generally grow in the tropics with an altitude between 200-2000 m above sea level with temperatures between 14-25 C. Tea is a plant that has many uses, one of them as an antioxidant. Tea is usually processed and packaged in the form of tea bottles, tea bags, tea tubruk and other tea preparations. Drink tea can we look back to the 10th century BC in China before spreading to Korea and Japan. Basically, tea drinks are made by brewing the tea leaves to make the extract. Because of the chlorophyll and other pigments in the leaves, the extracts generally appear in brown. Currently the most widely produced tea packaging is tea bags, this type of tea is favored because of its practicality because it makes it necessary to filter, directly brewed and enjoyed, but the same kind of other species that produce tea and residual waste is usually disposed to the place rubbish without using it again first
A total of 5 tea teabags are included in 200 ml of water and boil the purpose of this process is to extract the tannin compounds present in the tea, tannin is a compound commonly used in the paint and ink industry, after boiling the remaining tea separated and filtered for take the remaining extracts.
After boiling the solution is added 3 grams of spikes which are the source of iron or Fe3+ which functions to make the colored ink black, then added 20 ml of 25% vinegar solution which aims to strengthen the color of the ink, vinegar especially dilute acetic acid solution which is an important reagent and industrial chemistry, primarily used in the production of cellulose acetate, cellulose acetate is a compound used as a basis in the manufacture of photographic film and the base film is a transparent substance that acts as a support medium for photosensitive emulsion. then given filler substance ie cornstarch.
After that added emulsifiers in the form of 2 grams of CMC which aims that between tannin dyestuff can be more united again with water used as a solvent. The addition of cornstarch in making the ink is intended as a filler so that the ink is thicker. Furthermore, to know the ink results with different variations of different materials was done experiments again with various composition of the material.
To make a good ink result, this experiment conducted several experiments with a variety of material composition, the first composition (label B) is a mixture consisting of 200 ml of residual water added 2 grams of cornstarch, 2 grams of CMC and the addition of 40 ml of vinegar it aims to know how the ink results with the addition of more vinegar than without the addition of vinegar.
In the subsequent ink-making (label C) uses the same composition as on label B, it’s just that without the addition of vinegar solution, from the experiments it is found that the ink made is obtained overgrown by the fungus, this shows that the vinegar in the manufacture of this ink other than as a color stabilizer , vinegar can prevent the occurrence of mushrooms present in the ink made, vinegar is an acid which is a giver of hydrogen atoms. Warming vinegar makes this reaction quicker. When poured onto the metal, the acid releases hydrogen as a gas, but some of this gas remains in the liquid.
Tea is the source of tannic acid, the Fe3+ of the spikes will stick to the tannic acid to form tannat iron, the reaction can be written as follows
Iron III + tannat acid = iron tannate
Iron tannat is a black giver on this made ink. In order to stabilize this complex, vinegar is used, so the complex is formed more stable, in addition to this experiment showed that the addition of two vinegar volme showed a slightly darker color in appeal by using 20 ml vinegar volume.
To know the result of ink that have been made then do some test to ink, first test is viscosity which aims to know to know level of viscosity of ink of tea left have been made, The second test is surface tension test to know the ink capability attached, then tested paper chromatography to determine the color composition of tea ink residue and organoleptic test to determine the level of community acceptance of tea ink residue
From the experimental results for the ink A obtained viscosity of 1.112, the surface tension of 12.43 dyne / cm and and on the chromatography there is one color, while in ink B obtained viscosity value of 1.142, surface tension of 11.56 dyne / cm and paper chromatography there one color, being tested on ink sold on the market generally obtained the following data, viscosity of 1,100, surface tension of 8.15 dyne / cm and showed one color on the test chromatography that is black
From organoleptic results with small brushes and markers, the color is a little more pale than the ink sold in the market and the drying time is longer than the commercial ink in general. This ink is safer and relatively harmless when compared to commercial ink on the market this is because ink residual tea is made from materials that can be fed and drunk by humans, other than that the materials are easily naturally degredation