subject: Offset Plate Making Its Process Control Precautions - Offset Printing, Platemaking - Printing [print this page] Increasingly competitive printing industry, offset printing technology more and more mature. To improve product quality, often have to start from printing details, meticulous and thoughtful consideration of their production materials and production technology. Pressure with small offset printing, printing and deformation smaller, original representation effective, soft colors, dot clear, rich layers printing, print quickly and less wear and tear and so on, it is widely used in the printing of various products, particularly suitable for printing chromatic transition network version, lines, small text, etc.. Is combined with my years of experience, technology for offset control of peers of the industry with you.
I. Design Control plate technology 1, printing layout field version of the same color should be avoided with small text, lines, and the transition network, so as to avoid the pressure, volume and so can not take into account ink resulting paste version of dot gain or ink layer thick enough such phenomena, affect product quality .
2, print overlay between the various version of the site, one version of the overlay shall make the appropriate edge of the expansion and contraction are not allowed to overcome the resulting overlay the edge of "scab in crude" phenomenon.
3, four-color printing, plate making film output to be careful in screen angle. Typically, the screen angle Y90 , M45 , C75 , K15 , the general perspective of the main color version of cable options for 45 .
Second printing process technology control 1, the printing environment of temperature and humidity control.
Good control of temperature and humidity workshop is to improve the accuracy of product overprint an important part of the workshop offset relative balance of temperature and humidity should be maintained and the temperature should be maintained at between 20 ~ 25 , humidity should be maintained at 50% to 60% between.
2, offset PS version Reasonable choice. Offset Printing PS version to play an important role, it is primarily light-sensitive layer and the version of the base of two parts, the thickness of 0.15 ~ 0.3mm, the photosensitive layer after exposure required to have a good pro-oil, version of the base have a good hydrophilic. PS version should satisfy the layout formation, thickness uniformity, dimensional stability, distortion, surface cleanliness, dot reduction, good, high resistance to printing, printing ink, good balance, easy on the basic properties of dirty.
3, Blanket Reasonable choice. Blanket as a media transfer imprinting on offset quality of a great, correct selection of blankets on the improvement of product quality plays an important role. Blanket from the synthetic rubber and Textile Fabric composition, the textile fabric layer is usually 3 to 4 layers of fabric to fit on the synthetic rubber is made. The selection of blanket should be in line with good appearance, smooth and high, good elasticity and good ink transfer, a small amount of compression deformation, high tensile strength, elongation is small, the surface characteristics of a good principle of rubber. It should also be printed according to different printing materials, inks and graphics, choose different types of blankets.
4, offset printing ink balance control. Effects offset ink balance of factors, including the imprinted ink film thickness, the nature of printing paper, ink performance, workshop temperature and humidity, Fountain Solution And so on. Fountain solution which features a greater impact, especially fountain solution of pH value and conductivity of a direct impact on the quality of printing plates, ink drying speed, surface tension and so on. Under normal circumstances, the conductivity of fountain solution should be between 800 ~ 1200 /cm, preferably between 800 ~ 900 /cm, if higher than 1200 /cm will ink emulsion is increased, resulting in fuzzy networks; If less than 800 /cm will cause dry version, so that printing a blank part of the dirty goods. Fountain solution of the pH value should be maintained at between 4.5 and 5.5, when the clearest network. If you easily fall below the 4.0 version, more than 5.5 tend to plug. Therefore, good control of ink-water balance, it is necessary to as small as possible fountain solution supply, so that adequate printed materials attached to a thick ink, should be avoided, "ink big flood," the balance of law printing.
5, offset printing color sequence arrangement of the control.
