Skills of making spot color version of the hottest

Skills of making spot color plate by Coredraw

if you are careless in making plate by computer, especially in making spot color plate, there will often be some problems that do not conform to the printing process. External force P will cause the deformation of internal deformation of the sensor, resulting in huge losses. The following is an example to illustrate

case a, B, C spot color block. A refers to bronzing (regarded as a spot color here), B refers to brown block, and C refers to light yellow block

when designing with Coredraw, we often make a rectangle filled with 100% y for the a color block and a rectangle filled with 100% y, C and m for the B color block, so that we can output a field color plate independently, which is independent of the actual printed color. During the actual printing, the spot color ink controls the color. Then put C as the layer, B as the second layer, and a as the last layer together. In this way, the blocked areas of each layer are automatically hollowed out, and three plates with just set boundaries and no overprint boundaries can be made. It's easy to do this, but it's easy to have problems when printing. Especially after multiple versions are assembled into a large version, due to the large format, the paper is easy to deform, and the trailing place will appear. What if the experimental machine fails and the reason cannot be found? Don't worry about the phenomenon of white leakage due to inaccurate overprint; When bronzing, open the oil feeding valve slowly. Due to the heating, the paper is more likely to deform and leak white

how to solve these problems? The answer is to trap. That is, add a common overprint edge at the boundary of the two color blocks to make up for the phenomenon of inaccurate overprint surface leakage caused by paper deformation or other reasons

how to make it in Coredraw

therefore, method 1: make a file for each color plate separately. A color block makes a box separately according to the actual size; When making the color block B, increase the outer boundary by 0.3mm, so that there is a common overprint edge with the color block a, and dig out a positive circle in the middle according to the actual size; The C color block is made into a perfect circle, and the surrounding is also increased by 0.3mm, and there is a overprint edge with the B color block. In this way, three printing plates are output from three files to avoid automatic hollowing out of layers in one file without public overprint edges. When printing, first print block C, then block B, overprint light colors with dark colors, and finally bronze block a to avoid white leakage. It is troublesome to form several documents in this way. Moreover, because the color plate is divided into several files, the size of the layout center is not easy to control during production and rip processing, and the output film will be inaccurate due to the different size of the layout center

method 2: make only one file for this file. Like the above method, we can make three color blocks respectively. A color block is the first layer, B color block is the second layer, and C color block is the last layer. Finally, select all three color patches, click the right mouse button, and select "overprint fill" in the pop-up menu option. After this treatment, the blocked "layer" will not be dug out, but will remain as a public overprint edge. This is a better way. It is also worth noting that when exporting EPS format files, the trapping priority should be "maintain document overprint settings"

in addition, in the output center, rip processing parameters should also be selected accordingly. Taking founder century pspnt as an example, the "allow users to customize hollowing parameters" should be selected, and the graphic hollowing parameters should be "no hollowing", so as to ensure that the final output plate meets the printing process requirements