Awareness of the impact of paper on printing
paper is paper and cardboard collectively, it is made of plant fibre, fillers, pigments, plastic material and so on. In the process of packaging and printing, to ensure the quality of printed products, you should have the five factors: human, machine, material, method, ring. Then the paper as one of the five factors---the main ingredient, paper quality for printing what is affected?
, the impact of poor smoothness of the paper for printing
smoothness refers to the paper surface that is flat, level, it depends on the paper surface topography, embodies the characteristics of surface structure of the paper. If you want to get a good printing quality, smoothness of the paper is a necessary condition for it during the printing process, the paper surface with degree of inking rubber blanket surface contact, influence the transfer of ink full, graphics and text are clear. First, because of the poor smoothness of the paper, affect the amount of ink required of paper to make blanket ink film thickness will increase the printing ink is not uniform, resulting in printing graphics and text of dot, increased mechanization of the dot. Second, because of the smoothness of the paper, affect paper describes uniform, causing flooding and printing graphics and text, issued, and there are serious points loss.
Second, the effect of characteristics of compressive deformation of paper on printing
for printing paper, not only has better compression, but also suitable for multiple color printing, under pressure after removal of the moment, quickly restored properties. This is because during the process of printing, printing paper deformation under pressure, can produce a kind of buffer, paper and rubber roller, good contact, allowing ink to transfer evenly. If you are printing on paper has a higher compression ratio and does not have a high elastic recovery, multiple-color printing, through a series of compression, fast recovery, make the paper size or shrink, it will seriously affect the printing quality printing products.
three, poor surface strength of the paper
impact on the printing surface strength refers to the surface of the paper fibers, rubber, fillers or surface coating of paper between particles and the bonding strength between coating and paper-based. In printing process in the, if printing paper of surface degree poor, paper of surface and inking of rubber cloth separation, ink of separation force is greater than paper surface particles between of combined force, print of graphic edge, will will see white side or printing not real, and issued, phenomenon, this is printing in the of picking phenomenon, on printing of effect main has two a aspects:
1. caused graphic part of pollution. Mainly reflected in:
① after the spalling of the paper, as there are no white spots caused by stained with ink.
II is due to paper dust or the result of a paint brushed micro-pollution.
2. offset blanket and ink roller wash times increased. Due to the surface of the paper less, easy material, powder, blanket washing increased, significantly affect the print production.
four, paper pH
impact on printing in the printing process, the fountain solution PH values the normal range is 4.8~5.2, because of the printing paper used by the acidity of different, there will be different, different impact on printing. Acidic paper will cause corrosion and viscosity version of the printing plate, directly affect the oxidation of imprinting conjunctival dryness. From normal printing paper of the different results, more acidic, and faster the ink drying, this is because the acidic paper will absorb the ink in the desiccant, inhibit imprinted oxidation result of the conjunctiva. The contrary, paper is alkaline, alkaline substances in the paper will be delivered to the tank, neutralized with fountain solution in the water tank, a direct impact on control of PH value, so that the ink emulsification, resulting in printed products on the part of dirty, affect the quality of the product.
paper has a big influence on printing, printing paper used in libraries, strict search paper smoothness, compressive deformation properties and surface strength, acid and alkali, and avoid the printing paper is good or bad, affects the quality of printing products.