Spot color deployment of the hottest ink I

Spot color allocation of ink (I)

I carefully analyze the color draft or sample draft before allocating ink

when analyzing the color manuscript, it is mainly to analyze the color on the color manuscript and the ink used. Its basic principle is: the three primary colors of pigments are the basic colors for the deployment of all ink colors, and they cannot change without their roots. At the same time, it is necessary to make clear whether the color manuscript is mainly printed by line or on-site. If it is mainly line printing, it is necessary to focus on the consistency of the bottom color when allocating ink. If it is mainly field printing, it can focus on the color of the face when allocating ink. If there is both, both the bottom color and the color of the face should be taken into account when allocating ink

when the color manuscript is analyzed, the color of the ink used should be analyzed. Generally speaking, the ink deployment operator or captain is particularly sensitive to the observation of the ink color, and can see the components, such as yellow ink. They should be good at distinguishing whether it has low noise, stable and solid output, and whether it has yellow phase or blue phase (or green phase). For magenta ink, they should be good at distinguishing whether it has red phase or blue phase (or purple phase), For green ink, we should be good at identifying whether it is red or green (or yellow). If green ink is mixed with green ink with red phase and yellow ink with red phase, the mixed green will be dimmed, because this is actually equivalent to adding magenta ink to green ink and yellow ink (Yellow + Green + product and its subsequent cost red = black). Therefore, the observation of ink color is a necessary basic skill for offset printing operators

II. Basic principles for the deployment of spot color inks

whether dark or light spot color inks, the deployment should follow the basic principles, which are based on Printing chromatics and printing technology. The main contents include the following ten points:

(1) try to use the same type of ink and auxiliary materials. In addition, the color that can be mixed with two primary color inks should not use three primary color inks. Similarly, if you need some kind of intermediate tone matching, you must also use intermediate primary ink to avoid reducing the brightness of the ink and affecting the color and brightness. When mixing dark ink, put the main color ink into the mixing tray according to the weight of the ink, and then gradually add auxiliary colors and necessary auxiliary materials

(2) where diluents are used as the main ingredient, and primary or dark inks are used as the auxiliary, the blended inks are collectively referred to as light inks. The blending method of light ink is slightly different from that of dark ink. It is to gradually add dark ink to light ink. Do not take the dark ink first and then add the light ink, because the tinting power of the light ink is poor, and the oil overflows back to the mailbox. If you add the light ink to the dark ink, it is difficult to adjust the hue, which often makes the ink more toned

(3) prepare small samples before preparing spot color ink. This means to preliminarily judge the ink color to be used according to the hue of the original, then weigh a small amount of ink from each color of ink in proportion with a balance, accurately weigh it, put it on the ink mixing table, adjust and match it evenly, scrape a small color sample with a scraper, check it with the original sample, make relevant records, and keep it properly

(4) when blending multicolor spot color inks, use the complementary color theory to correct the color deviation. For example, when the purple flavor in a multicolor ink is too heavy, yellow ink can be added to correct it; If the red flavor is too heavy, you can add green ink (such as malachite blue or sky blue ink) to correct it; Another example is that when the black ink is yellow and the blackness is not enough, a small amount of light emitting blue can be added as the color enhancer, because light emitting blue is a blue ink with red light, which is conducive to improving the blackness of black ink

(5) master the hue characteristics of common inks. In the actual operation process, we must master the hue characteristics of commonly used inks. For example, in the deployment of light lake green ink, sky blue or Malachite blue should be used, and dark blue should not be used, because the dark blue ink has a red flavor, and the color will inevitably be gray and not bright after adding. Similarly, the dark yellow ink that is red should not be used, but the light yellow ink that is blue has a better effect. For example, when deploying orange ink, try to use golden red ink, because the color phase of golden red ink is red and yellowish, It can increase the brightness of the ink. In addition, the selection of some inks depends on the picture effect. For example, the inks selected for printing portraits and landscape paintings should be different

(6) pay attention not to make better and more exquisite experimental machine equipment, and the proportion of ink. Generally speaking, the proportion of inks is different. Inks with similar proportion are easy to mix, while inks with too large proportion difference will cause printing problems. For example, green ink mixed with lead chrome yellow ink and Malachite blue ink with a large proportion will float up and sink if it is put away for a long time, resulting in floating color problems. If we use yellow ink made of organic pigments to mix, our disease will disappear. In addition, due to the large proportion of white ink, in addition to covering requirements and adding a small amount of color matching when necessary, try not to dilute it with white ink (if the live parts of the lamination are another matter), so as to prevent the occurrence of quality problems such as poor color stacking and fading

(7) choose diluents reasonably and master the degree of dilution. When the hue and ink amount are determined, the diluent must be reasonably selected, for example, the diluent used in offset paper and coated paper is different. In addition, the degree of dilution is an important technical link. If the dilution ratio is small, the printing surface is easy to be scratched, the ink layer is dry and not solid, and the color is not bright; If the ink is diluted too much, only by increasing the thickness of the ink layer can the hue required for printing be achieved. In this way, it is easy to make the low-key area of the page paste, so that the depth and depth can not be distinguished. At the same time, there will be through printing. In addition, the original ink that is not resistant to light, oxidation and easy to change color should not be used to allocate light color ink as far as possible, so as not to cause color instability

(8) the paper used for preparing spot color ink scraping should be consistent with the printing paper to avoid color differences caused by different papers

(9) when mixing spot color ink, pay attention to the consistency with the printing sample density. Generally, when the newly adjusted new ink is close to the color of the printing sample provided by the customer, the color will change after the new ink dries, so the newly adjusted new ink cannot be lighter than the printing sample in color

(10) take into account the characteristics of post press processing. When choosing ink, we should consider the post press processing. If the print needs glazing, we can choose general ink. If we choose the ink with good friction resistance, it will not only cost high, but also affect the glazing effect