Copperplate paper is developed with the screen printing, because the uncoated paper fiber composition of the surface unevenness and degree than the diameter of the dot is much larger, some dots happen to be in the gap between the fibers and can not transfer the ink to the paper, so that the image pixel in this part can not be reproduced. Paper coated with pulp and then calendered, the surface of the paper particles smaller than the diameter of the dot, the pulp is also better than cellulose fibers, so the dot can be correctly reproduced. Obviously, coated coated coated paper printing performance is better than uncoated offset paper.
The original paper of coated paper is made of high-quality rolled newsprint or offset printing paper, and the high-grade coated paper is made of special original paper. The surface coating is firmly adhered to the original paper. The paper surface is then super calendered, with a firm coating, no bubbles, no streaks, strong gloss and high smoothness. The smoothness of coated paper is generally above 600s, which is more than 10 times higher than that of offset paper. This makes the coated paper can be in close contact with the printing plate and print out the dot clearly. The pH value of coated paper is around 7, which has no adverse effect on the lithographic wetting solution and no adverse effect on the ink drying process. In the copper plate paper ink adheres quickly, dry quickly, and after drying can also set out the gloss, good reproducibility of the network point, the ink layer is thin and clear image, the network is clean. The dimensional stability of coated paper is also better than offset paper, and printing on coated paper can meet the requirements of accurate overprinting. The tensile strength and surface strength of coated paper is also high enough to resist the greater tensile force generated by the more viscous ink film used. Because of the above, coated paper is often used to print high-grade printed materials
Post time: Jan-03-2023