Paper is an important part of printing supplies. It is good or bad determines the stability of the printing process and the quality of print quality.
Paper is a larger part of the cost of printing. As global pulp prices rise, paper prices are soaring. Making the printing business, printing costs are high. Choosing the right paper to reduce the consumption of paper during printing is an efficient way to increase the profits of the printing industry.
In the purchase of paper is to take into account some of the parameters of the paper:
1. whiteness: refers to the extent of the white surface of the paper. Usually called magnesium oxide is 100% white, the whiteness of the paper is relative to this 100% white. In the printing of high brightness of the paper is generally used for relatively beautiful prints, high whiteness of the relative difference in print on the large, rich layers of print, color reproduction is good. At the time of purchase, the printing plant should determine the required whiteness range and the high whiteness paper according to the printing effect required by its own printing business because the internal impurities are relatively small and the price will be relatively high.
2. Quantitative: refers to the weight per unit area of paper, also known as weight. Different prints require different amounts of paper. In general, the newspaper printing generally use low-quality paper, packaging and printing generally use high-quality paper. The higher the amount of paper, the greater the paper will be tight, printed out of the print reproduction capacity.
3. Smoothness: the time required for a certain volume of air to pass through the gap between the specimen surface and the glass surface under a certain pressure at a certain degree of vacuum. Smoothness is an indicator of the degree of convex and concave characteristics of paper or paperboard, which is very important for printing paper, which affects the uniform transfer of printing ink. The smoothness of paper or paperboard is affected by factors such as fiber form, pulp beating degree, papermaking and blanket weaving methods, wet pressure and embossing, filling and coating.
4. Surface tension: also known as pull hair strength. Is the strength of the separation between the paper coating layer and the paper. Some paper because of too much additive, in the printing will produce nap, drop off the phenomenon, which is caused by the paper surface tension is too low. In the optional paper is to pay attention to the paper surface tension requirements.