Flower paste version 0 in the most popular offset

In offset lithography, the dot of the printing plate image is abnormally reduced Spread out Fuzzy, called flower paste version In fact, they are a pair of faults in the opposite form -- embossed version and pasted version This kind of fault is also the most common phenomenon in lithography

I The stencil

dot shrinks on the printing plate when dot printing emptiness. Vanishing static experimental machine mainly includes, which is called flower plate Small lines on the printing plate The disappearance of words is also called flower edition When the pattern occurs, the high-profile details will soon be lost In the field printing products, due to the destruction of the lipophilic base of the plate base, there is a white phenomenon, also known as the flower plate

the main causes of stencils are fountain solution and friction

1. First, it refers to the amount of fountain solution and the acidity of fountain solution Large amount of fountain solution will aggravate emulsification, shrink dots, lose fine dots, and produce stencils The strong acidity of fountain solution will produce similar results

2. The friction of the printing plate comes from the water roller ink roller. Contact between rubber sheets The amount of friction depends on the parallelism between them Pressure magnitude and surface condition The friction that causes the printing plate to bloom mainly depends on the water roller and the maximum friction between the blanket and the printing plate If the paper degrades seriously during the printing process, this friction will be aggravated

II Paste

the characteristics of paste are: the layout points expand and deform, adhere to each other and merge, so that the level of printed matter is blurred It is mainly reflected from the low-key part of the image

there are many reasons for paste, and the main reason is water delivery Inking and pressure

1. There is a close relationship between water conveyance system control and paste plate Small amount of water, ink is easy to expand, so that the dot spread, can cause paste A small amount of output increases the emulsification of ink, which is also said by kjeld Kirk Kristiansen, the owner of cola high, so as to cause a paste version Because the emulsifying ink is not oily, it floats to the fountain solution at will. It first expands outward at the medium and low key points to form a paste

2. Too much ink is caused by the paste version for easy connection and communication; One of the basic reasons Because of the large amount of ink, it will be made, but at present, it becomes a little expanded, and over time, it forms a paste version Too thin ink is also the reason for the weight of the paste version Thin ink flow too much, after extrusion, there is a paste phenomenon