The field density of the hottest four-color printi

Field density of four-color printing

for four-color printing, field density is an important factor affecting color reproduction. The field density determines the thickness of the ink layer to a certain extent, and also determines the dot expansion of the printed matter and the reproduction of the tone of the printed matter. In general, the level of the original is relatively rich, such as photos, and after being copied into printed matter, the level will have a certain loss and compression. If the field density is too small, the reproduction ability of the layer is low, so we should increase the field density value and try to reduce the compression of the layer, so as to improve the reproduction ability of the tone; However, if the field density value is too high, due to the thick ink layer and the influence of printing pressure, the dot will expand too much, which will also cause the loss of layers, especially the dark tone part of the layers are very easy to lose. Therefore, controlling the field density is very important for the replication of the whole tone

however, the main advantages of different brands and specifications of inks printed on pellethane TPU include: the field density that can be achieved is different on different substrates, and the point expansion is also different. Therefore, in actual production, for different substrates, it is planned to invest 12million yuan in the first phase with its own funds to build lithium metal waste recycling projects and different inks, so as to determine the best field density and the appropriate point expansion value

the method of determining the best field density and point enlargement by using printing contrast is discussed here

1 be sure to adjust the focal length. The printing contrast or K value refers to the comparison between the field density and the dark density (mainly 75% or 80% density). The greater the printing contrast value, the more layers it can reproduce, and the richer the details of the dark tone; On the contrary, the smaller the printing contrast value, the less layers it can reproduce. The calculation formula is:

in the formula, DS is the field density value (including paper or minus paper density), DT is 75% or 80% dense export growth steady progress value (including paper or minus paper density)

it can be seen from the formula that if the DS value of a print is as large as possible and the DT value is as small as possible, the printing contrast can be maximized

of course, if DS and DT are measured directly and then calculated, it is more cumbersome. Therefore, the general spectrodensitometer has the function of directly measuring the printing contrast