Ink And Ink Manufacturing A consideration when selecting an ink is the eventual use of the printed item. For example, food packages should be printed with an odorless ink, ink on feather flags used outdoors must be able to withstand the weather, products that will be handled by young children must be printed with non-toxic inks, ink printed on table cloths should hold up under repeated washings.
Printing inks Ink Ink is transferred from a plate or stencil to paper or some other material during the printing process. The ink forms the image on the printed product. Over two thousand years ago, the Chinese made and used inks to print from wood blocks. Most printing inks consist of pigments, vehicles, and modifiers. Pigment is the ingredient that provides the color of the ink. Many pigment colors are produced from rocks and clays. Others can be traced to plants, sea life, or even insects. Several pigments may be blended together to obtain a desired color ink. The vehicle is the fluid that carries the pigment. Oil, lacquer, alcohol, and water are all used as ink vehicles.
Modifiers may be added to ink for certain desired characteristics. For example, driers are added to speed up the drying process. Waxes are used to minimize setoff. Setoff refers to the transfer of ink from a freshly printed sheet to the back of the sheet above. Ink manufacture Ink manufacturing is complex and requires extensive chemical and printing process knowledge as well as specialized ink manufacturing equipment use. While there are a number of manufacturing methods, most share these basic phases of production: formulating, premixing, milling, filtration, and testing. Selecting the right ink for the job Each printing process requires the use of an ink developed specifically for that process.
Letterpress, gravure, lithographic, and screen-process inks are specially formulated to match the requirements of the printing process. For example, letterpress inks are designed to distribute evenly over and adhere well to raised plate surfaces. Gravure inks are quite fluid and dry rapidly. Lithographic inks are formulated so as not to absorb or combine with the fountain solution in the press. And inks used for screen-process printing will have the consistency of thick paint, which is usually required in this process.
