In the packaging and printing industry, the ink absorption of paper refers to the ability of paper to absorb ink. It is related to the absorption of low viscosity components of ink by paper pores and the penetration of some components of ink into paper. It is one of the important factors affecting printing quality.The Absorption Process Of Paper To Ink Is Introduced In Detail.
The second stage is from the paper leaving the embossing area until the ink is completely dry. This stage mainly depends on the capillary action of the paper to absorb the ink, which is called the free penetration stage. At this stage, the connecting material is separated from the whole ink and enters the interior of the paper at a fairly slow speed through small pores and the rough surface of the paper fiber.
Therefore, this process is actually a process in which the connecting material is transferred from the ink to the paper hole, and the connecting material is separated from the ink as a whole. Therefore, the properties of the conjunctiva retained on the paper ink film will change, and the fixation and drying of the ink must also be completed in this process.
At this stage, the absorption rate of paper to ink determines the gloss of printed matter, whether printing and pulverization will occur. When the ink is transferred to the paper, with the passage of time, the low molecular connecting material (solvent) begins to penetrate into the paper layer, the solvent content in the ink layer decreases, the viscosity of the ink increases, and the ink layer condenses.The Absorption Process Of Paper To Ink Is Introduced In Detail.
The ink absorption of paper depends on the number of paper capillaries and the diameter of capillaries. Paper is a porous material. There are many gaps between fibers, filling materials and pigment particles in the paper, which are equivalent to many capillaries. Under the action of these capillaries, the binder in the ink can be absorbed, and the thicker the diameter of the capillaries, the faster the absorption of the ink. Therefore, the pore structure of the paper determines its absorption of the ink.The Absorption Process Of Paper To Ink Is Introduced In Detail
The looser the paper, the larger the pore, and the stronger the ink absorption. For example, because newsprint is loose and has strong ink absorption, the ink transferred to newsprint is firm, which is conducive to improving the printing speed.The Absorption Process Of Paper To Ink Is Introduced In Detail.
Coated paper is looser than offset paper and has larger pores than offset paper, but the fixation of ink is not necessarily slower than offset paper. There are two main reasons. First, the ink supply during coated paper printing is small. The Absorption Process Of Paper To Ink Is Introduced In Detail.
Second, there are countless small capillaries between the pigment particles attached to the surface of coated paper. The absorption capacity of many fine capillaries is much greater than that of a few coarse capillaries. In addition, the coated paper has strong absorption selectivity to the connecting material, so that the low molecular components with strong fluidity in the connecting material penetrate into the paper, and the high molecular components in the connecting material are still retained in the ink layer, so the firmness and gloss of the ink layer can be improvedt.The Absorption Process Of Paper To Ink Is Introduced In Detail.