Additives used in the printing process

Acetic acid, talc, clove oil... What are the uses of these substances in printing companies? Below, this article will introduce some commonly used and very-used inks and various fountain solution additives that make the printing process faster and smoother.

When printing, we all hope to reduce the number of shutdowns during the printing process to increase production efficiency. One way is to prepare some necessary ingredients to avoid common problems in the printing process. There are many additives that can be added to the ink and fountain solution to make the entire printing process go smoothly.

Of course, the quality of presses, inks, and paper substrates used in specialized print jobs is a key factor in the final print quality. However, we should not neglect or underestimate some of the “little things” that can and often are used in the printing process. Correct use of various auxiliaries during the printing process will result in a more satisfactory print quality. How to use these additives is very important.

Ink additives

The operator of each press knows the importance of high-quality inks in the printing process, and to obtain the best operating results, several additives are always ready even for the most effective inks. These additives include water-repellent varnish, chalk desiccants, manganese desiccants, detackifiers, and gloss oils.

Water-repellent varnish can be used to increase the viscosity and consistency of the ink, and also to solve the problem of over-emulsification of the ink. A varnish of about 15% by weight is added to the ink to achieve the desired effect. For example, add 2.4 ounces of varnish to each pound of ink.

Chalk desiccants should be used for jobs requiring the highest wear resistance. This is a water-activated desiccant that only needs 3/4 ounces of chalk desiccant per pound of ink.

Use a stable and full-effect manganese desiccant to speed up drying. This will shorten the working hours and allow reverse printing at a faster speed. As with the chalk desiccant, only 3/4 of the manganese desiccant is required per pound of ink.

As the name implies, the dispersant can reduce the viscosity and adhesion of the ink, and by softening the ink to increase its fluidity between the rollers, a 1/4 ounce release agent is added to each pound of ink.

Adding bright oil to the ink can increase the gloss of the ink on the surface of the coated paper, and can also improve the transfer performance of the ink to the transfer roller. Like the water-repellent varnish, the operation should add about 15% of the weight of the ink. Shine on the oil.

Fountain solution additives

The use of fountain solution additives can increase the efficiency and quality of printed output. Like ink additives, these addenda are not necessary to complete the printing operation, but if used properly, the printing process can be made smoother and more efficient. The most effective fountain solution additives in the pressroom are cobalt dried catalyst, gum arabic and alcohol.

The addition of a cobalt-dried catalyst to dampening reduces the drying time on the surface of the ink film and is used when printing on nonporous substrates such as metal foils and plastics. The recommended dosage is 1/2 ounce of dry catalyst per gallon of fountain solution.

Gum arabic has the function of improving the hydrophilicity of the non-image area of ​​the metal plate. About 1/4 ounce of gum arabic should be added to each quart fountain solution. However, note that gum arabic will fail when the pH of the solution reaches 5.0 or above.

To reduce the surface tension of the water film and increase the water film viscosity, just add isopropyl alcohol to the fountain solution. The alcohol causes the ink to solidify and dry faster because it makes the water film very thin and takes away with rapid evaporation. Most of the water. Depending on the printing plate and the wetting system, adding 10% to 15% alcohol to the fountain solution can be very effective.

Home formula

It is said that in some very creative companies, printers have created their own "home formula" to improve the printing process.

Although many printing companies have chosen the common additives described above, some companies have also turned to the daily use of common ingredients. These daily ingredients include corn starch, talc, clove oil, tartar butter, linseed oil, and ammonia without detergents. acetic acid.

Corn starch is often used to thicken thick soups and other sauces, and some printers add it to very soft inks to achieve the same effect. It hardens the ink, has better water resistance and paper compatibility. However, it should be used in small amounts: It is recommended to add about 1/4 teaspoon of starch per pound of ink.

Although talc can be found in almost every ordinary family, its presence in the printing shop is not necessary. Talc is the best additive to reduce ink splash defects. It shortens the length of the ink, and it should also be used in small quantities: about 1/2 teaspoon of talc per pound of ink.

Clove oil is used daily as a drug to relieve toothache when people do not want to see a dentist. However, this effective local anesthetic is also beneficial to printing companies and can be used as an antioxidant or anti-skin agent to add ink. The recommended dosage is 0.5% clove oil per pound of ink.

Tartar butter is not only a good binding powder in making meringues such as lemon protein pie, but also a good fountain solution additive when printing gold ink. Adding tartar cream to the alkaline solution can increase the metallic luster of the ink. One ounce of this powder is added to each gallon of fountain solution.

Another type of household material commonly used inside and outside the printing company is linseed oil. For centuries, carpenters have used this oil to renovate various wooden surfaces. Also, the addition of this oil to the ink prevents the ink from drying too quickly on the roller. The recommended dosage is 1/2 to 3/4 ounces of linseed oil per pound of ink. If the ink appears emulsified, then add another 1/2 ounce of water repellent varnish.

There are two other types of households that are most commonly used, but also used in printing shops are ammonia and vinegar. The use of ammonia can quickly increase the pH of the acidic fountain solution. About 1/8 ounce of ammonia should be added to each quart fountain solution, and the pH should be checked before and after adding ammonia. If the pH does not change significantly, Add 1/8 ounces of ammonia water. Note that ammonia should be used without detergent. Otherwise, excessive foaming will occur in the fountain solution.

Vinegar is often mixed with warm water (4 ounces of vinegar per 16 ounces). When printing alkaline paper, calcium deposits on blankets and rollers can be avoided, and blankets and rollers can be neutralized with this mixture. Extraction of calcium carbonate, calcium carbonate will destroy the ink balance and promote the substrate paste.

If using traditional additives is problematic, using these household products will often help us get out of trouble. However, although these methods are effective, they should only be used moderately if necessary because of different printing. There are different effects to be used by the operators, and these agents cannot be guaranteed to be equally effective for anyone. The safest method is to stick to ordinary materials.

Ink is clearly one of the most decisive factors in the entire printing process. However, it is also important to use the right additive for the highest print quality. At work, remember to use a good-looking ink type, and don't forget that you can also use additives to supplement. Ink suppliers can also help us choose the best ink and fountain solution additives to meet the requirements of special printing processes.

Source: Bison