An important tool for ink coloring - ink sticks

In the gravure printing production, because of the volatilization of the solvent in the ink tank, the uniformity of the ink is reduced, and the surface is easily formed into ink skins and ink sticks. After the printing roller is brought on, the scraping knife is not easy to scrape clean, so that the printing product produces paste plates, knife lines, etc. defect. To solve this problem, as long as the ink “flows” and mixes continuously, this situation can naturally be avoided. There are two means to move the ink: one is to use an ink circulating pump to let the ink circulate; the other is to place an ink stick in the ink tank to allow the ink to flow in the ink tank. The former is the external circulation of the ink, the cost is high, and the factors that cause failures are increased. Generally, the addition of the solvent and the automatic viscosity control system are not included in this article. From the point of view of uniform ink, the latter is the most economical and effective measure. Agitating rods are generally rods made of aluminum alloys, with spiral-shaped continuous protrusions on the surface, so-called "ripples" or unwinding lines, with magnetic material at both ends, which can be adsorbed on a plate roller. During the printing, the agitating rod floats on the surface of the ink, and when the printing roller rotates, it rotates in the reverse direction by the adsorption effect. When rotating, the corrugation drives the surface layer of the ink to allow the ink on the surface to move, thereby evening the ink and avoiding the corresponding quality problems of the printed product. The following are the two main factors that determine the quality of agitating sticks:

1. Effect The stirring of the ink stick is mainly based on the unfolding line, which is called ripple, and the size, angle, structure and rotation speed of the ink stick determine the effect of ink mixing. In general, the faster the agitating rod rotates, the better the agitating effect. The bigger the development line is, the larger the angle is and the better the ink mixing effect is. However, if the developing line is too large, the magnet part is far from the platen roller, the magnetic force is weakened, and the magnetic force is not easy to be absorbed. The rotation speed of the ink stirring rod is reduced (discarded), but the effect is poor.

2. Life Stirrer Because it needs to float on the ink surface, it is generally hollow. If the seal leaks, the solvent will enter the inside of the ink stirrer and it will sink and lose its stirring effect. Therefore, the seals at both ends should be resistant to corrosion. In addition, the surface wear resistance is better.

At present, the commercial agitating stick generally has the following kinds:

1, plastic stir rods are common in imported products, the surface is made of wear-resistant plastic sheet, the internal use of paper core, the quality is quite good, the price is relatively high, usually about a thousand dollars per meter. It is said that at present some people in China have already imitated it, but because there is no better friction-resistant plastic material, the life expectancy is relatively poor. In addition, the effect of ink mixing is also not very good.

2、Rope agitating rods are generally made of general aluminum tubes. The surface is wrapped around a wire rope to make a deployment line. This type of product has two defects: 1 Because the wire is wound around the wire, the angle of the deployment line is relatively small, and the 2 wire rope will be immersed. Ink bleed, difficult to clean when changing ink color.

3, single-strand aluminum alloy corrugated wrought iron rod structure with the same rope around the ink rod, but the wire rope to aluminum alloy spiral protrusion, because there is only a line of development, the angle is small, the ink mixing effect is relatively poor.

4, eight-wire aluminum alloy corrugated stirring rod Aluminum alloy rotary extrusion profiles, the surface has 8 lines of development, angle, is the best product of the current ink mixing. In addition, this type of product is not only more resistant to corrosion at both ends of the seal, and wear resistance is also relatively good, if the timely removal of iron powder and other impurities absorbed by the ink stick, the life is generally 2-3 years, it really saves the manufacturers of uniform Ink costs. This is also the product that most color printing plants currently choose. At present, Zhengzhou Weinna Electronics Co., Ltd.'s integrated magnetic eight-wire ink stirring rod, Henan's eight-wire ink stick is such a product. There is a problem of the ink reflow direction of the eight-line corrugated ink stick, which is actually whether the corrugation has an interface problem. If the left and right spirals are in the middle, the ink will flow from the middle to the end of the ink tank or the ends of the ink will flow in the middle (need to reverse the direction of placement); if the ink stick is a pattern (that is, there is no interface, regardless of the left-right rotation) When working, the ink will flow from one end of the ink tank to the other. However, these two ink-return methods basically have no effect on the uniformity of the ink.