The Effect of the Structure of Paper on the Luster of Prints

1. The effect of the surface smoothness of the paper on the gloss of the print.

In order for the printed product to be specularly reflective, colorful, and glossy, it must be printed on smooth paper. The rough surface of the paper is difficult to make the print glossy, even if the flatness is good, but the formation of capillary pores between the paint particles of the paper, the permeability of the link material is large, and still can not get high-gloss products. The surface smoothness of various papers is different, and the degree of smoothness has a great influence on the gloss of the finished product. The paper with high smoothness has good contact speed with the ink, and can ensure the complete reproduction of the dots, so that the finished product has better gloss. Because the gloss of the ink on the paper is determined by the specular reflection on the incident light, only the paper with high smoothness can produce specular reflection after the ink film is leveled. On the other hand, poorly smooth, rough-surfaced paper, with imprinted ink film unevenness, can only form a diffuse reflection of light, and the finished product is not shiny. Therefore, in order to obtain a good finished gloss, exquisite and high-grade products must first be printed on paper with high smoothness.

2. The effect of paper absorbency on gloss.

The ink absorbency of paper is actually the absorption property of the paper to the ink binder, and the absorption of the paper is one of the main conditions for determining the amount of permeation. If the ink has certain properties, the paper absorbs large, and the ink layer pigment overlaps and thickens. Gloss is reduced or even dull. The coarser the paper, the larger the fiber gap and the stronger the absorption of the binder. When the binder has not yet dried, most of the binder is absorbed by the fiber. The remaining binder and ink particles adhere to the surface of the paper, losing the leveling properties they should have, and failing to form a smooth ink film layer. The product is dull. For coating paper (coating paper), there are two main reasons that affect the ink absorption: First, the types of mystery tablets used in the coating and the use of materials. The lower the ratio of the adhesive to the pigment, the higher the paper's absorbability of the ink. With a low concentration of paint, the adhesive and water in the paint can easily penetrate into the thick paper, reducing the amount of adhesive in the coating, thereby increasing the ink absorption. The second is that pigments in the paint and particle fineness are also related to ink absorption. The finer the particles of the pigment, the less likely the glue in the coating is transferred to the paper base. The pigment particles are coarse, the gap between the particles is large, and the absorption of the ink is also large. Therefore, it is difficult to obtain an ideal gloss effect for the finished product.

3. The effect of paper gloss on the gloss of prints.

The gloss of the paper itself has a considerable effect on the gloss of the finished product. How the gloss of the coated paper surface depends on the light-enhancing materials used in papermaking and the precision of the paper. Light-enhancing materials include aluminum stearate, paraffin wax, insect wax, etc. The finishing method is super calendering. The paper processed by the above method has a smooth surface and forms a mirror reflection (unidirectional reflection) of light. The ink with higher transparency is printed, and the finished gloss effect will be better.

4. The effect of paper strength on the gloss of prints.

The paper has low strength, falling powder, and serious hair loss. When printing, the binding force between ink and paper is not high, and the gloss of the printed product is low or even dull.

5. The effect of paper pH on the gloss of prints.

The pH of the paper affects the drying speed of the ink film, and the drying speed of the ink film affects the gloss of the print. Alkaline paper can accelerate the drying of the ink film, thereby relatively reducing the penetration time and the amount of permeation of the linking material, so the gloss of the print is better; the acid paper is secondarily.