Using the inks of the above density, printing in the order of black, cyan, magenta, and yellow, the overprinting effect is good; if the printing sequence is changed to black, cyan, yellow, magenta, the ink film thickness turns to 0.73m, 0.82 in order. m, 1.43m and 0.96m. Obviously, the superimposition effect of magenta ink is not good. Even if the amount of magenta ink is increased in order to increase the overprinting effect of the magenta ink, the disadvantages such as color shift, gray balance on the printed matter, damage, and exaggerated dot enlargement will be brought about.
Brightness is an important indicator of ink performance. Among yellow, magenta, cyan and black four-color inks, the yellow ink has the highest lightness, and the black ink has the lowest lightness. The high brightness of the ink on the last color printing, make the print screen more beautiful, and the least light, dark color, such as black ink, should be the first printing.
From the above analysis, it can be seen that the factors constraining the normal operation of wet printing ink overprinting are far more than dry printing, and the overprinting sequence of multi-color offset printing presses is therefore relatively fixed. At present, it is recommended to use black, cyan, magenta, and yellow, which is determined by taking into account factors such as the prepress processing, printing process conditions, ink coloring properties, and other factors of general color prints (excluding prints for the under color removal process). . Production practice has proved that the use of this color sequence is beneficial for improving the ink-jet effect of a single-paper multi-color offset printing press. Some ink manufacturers produce four-color offset printing inks, the adhesiveness of which is greater than the smaller order is black, cyan, magenta, and yellow, which is also to adapt to wet printing wet ink superimposition printing color sequence.
Second, the printing color order of the color newspaper In China, for the printing press color printing machine organic offset, full-satellite, there are semi-satellite unit plus a BB machine modification machine, there is in the Y type With a Y-type unit on the crew, some big city printing houses have also added multi-color commercial web presses capable of printing copperplate paper. No matter which kind of color newspaper printing machine, it has realized the integration of printing, depreciation, accumulation, subcontracting and mailing. In order to pursue higher and higher timeliness, the entire process of printing newspapers is often completed in a matter of hours. The printing speed is high, and the time for stacking inks is shorter than that of multi-color offset printing machines. From the perspective of the structure of the printing press and the time interval of ink overprinting, the ink of the newspaper is superimposed on the wet printing method of wet printing, and the order of printing is more reasonable according to K, C, M, and Y of the multi-color offset printing machine for sheet-fed offset printing. .
With the exception of a few excellent newspapers for coated paper printing, the vast majority of color newspapers, like black-and-white newspapers, use newsprint with good surface, porosity, ink absorption, and flexibility, and reel-assisted reeling mainly with osmotic drying and oxidative polymerization and drying. Paper web offset ink printing. Under the influence of the imprinting force, the ink penetrates quickly into the micropores of the newsprint. The fixing and drying of the ink are carried out almost at the same time. The ink after printing is adhered on the ink layer that is printed first and is already drying. From the ink drying point of view, the ink printing of color newspapers is a wet-press drying mode of dry printing, and the color sequence is the same as a single-color offset printing machine, and the flexibility is large.
Caibao uses porous, easily deformable, and low-white newsprint paper. It is difficult to register on high-speed web offset presses, and the color reproducibility is worse than that of GJ and coated paper. Therefore, Caibao is a general printing product. The national standard newspaper print quality requirements and test methods code number GB-14705-93 stipulates: The quality of color pictures should be basically in line with the natural tone, four-color overprint accuracy. Therefore, in addition to considering the overprinting effect of ink, the printing color sequence of a color newspaper must not meet the requirements for color reproduction of newspaper color pictures in the national standard. The following is a detailed analysis of color printing press color sequence.
A newspaper printing house uses Canadian newsprint and Tiens high-speed web offset printing ink to print color newspapers. The adhesive Tack values ​​for the four color inks of K, C, M, and Y are: 197, 148, 155, 219, respectively. The printing sequence according to the wet printing should be Y, K, M, and C. However, the Goss rotary offset press used in this plant is a parallel unit type. The paper feeding route is long and the overlay accuracy is relatively difficult to control. From the point of view of printing overprinting, yellow should not be placed on the first color printing, while yellow ink is highly adhesive and should not be placed on third and fourth color printing. The black ink is placed in the first color yellow ink master printing in the second color, is conducive to the printing of the magnetic standard. On the surface, black ink is less visible than yellow ink, and the overprint effect is poor. However, when the penetrating dry black ink and the ink-absorbing newsprint paper are in contact, the ink is immediately fixed and dried, and the adhesiveness rises sharply. When the yellow ink is overprinted, no ink stripping failure occurs. Therefore, the color sequences actually used in production are K, Y, M, and C.
The adhesive Tack of the four-color inks K, C, M, and Y of the rotary lithographic offset printing system of Shanxi Gao's Rollei are: 192, 186, 195, 198. All kinds of inks have little difference in adhesion, and the color sequence is not affected by adhesion. Printing using this ink mainly depends on the structure and color reproduction of the printing press to select the printing sequence. If a Gaussian-style web offset press is used, the paper-drawing line is short and the registration is easy. The color sequence of C, M, Y, and K is used, which is earlier than the print registration and does not make the ink use larger. The dark ink of the black ink has a failure of ink stringing, and the color reproducibility is good.
Coated paper has a layer of paint on the surface. It penetrates smaller than newsprint paper. In order to dry and dry web-fed offset inks, it dries more slowly on copper than newsprint. Therefore, when printing on color paper with coated paper, the printing sequence should be Follow the pattern of wet printing ink overprinting. Once there was a newspaper printing house using Gaussian full-satellite web offset printing presses and 85g/m square copper printing China Computer News. The printing color sequences used were C, M, K, and Y. In the printing process, black ink sticks on the yellow plate, but the yellow ink does not transfer to the paper. Finding the cause of the problem, they measured the adhesiveness of the four-color ink and used a domestic YQM-IB viscosity meter. The Tack values ​​of Y, M, C, and K inks are 6.05, 6.75, 7.85, and 4.37, respectively. After adjusting the printing sequence to C, M, Y, and K, the ink transfer is normal and the overprinting effect is good.
Brightness is an important indicator of ink performance. Among yellow, magenta, cyan and black four-color inks, the yellow ink has the highest lightness, and the black ink has the lowest lightness. The high brightness of the ink on the last color printing, make the print screen more beautiful, and the least light, dark color, such as black ink, should be the first printing.
From the above analysis, it can be seen that the factors constraining the normal operation of wet printing ink overprinting are far more than dry printing, and the overprinting sequence of multi-color offset printing presses is therefore relatively fixed. At present, it is recommended to use black, cyan, magenta, and yellow, which is determined by taking into account factors such as the prepress processing, printing process conditions, ink coloring properties, and other factors of general color prints (excluding prints for the under color removal process). . Production practice has proved that the use of this color sequence is beneficial for improving the ink-jet effect of a single-paper multi-color offset printing press. Some ink manufacturers produce four-color offset printing inks, the adhesiveness of which is greater than the smaller order is black, cyan, magenta, and yellow, which is also to adapt to wet printing wet ink superimposition printing color sequence.
Second, the printing color order of the color newspaper In China, for the printing press color printing machine organic offset, full-satellite, there are semi-satellite unit plus a BB machine modification machine, there is in the Y type With a Y-type unit on the crew, some big city printing houses have also added multi-color commercial web presses capable of printing copperplate paper. No matter which kind of color newspaper printing machine, it has realized the integration of printing, depreciation, accumulation, subcontracting and mailing. In order to pursue higher and higher timeliness, the entire process of printing newspapers is often completed in a matter of hours. The printing speed is high, and the time for stacking inks is shorter than that of multi-color offset printing machines. From the perspective of the structure of the printing press and the time interval of ink overprinting, the ink of the newspaper is superimposed on the wet printing method of wet printing, and the order of printing is more reasonable according to K, C, M, and Y of the multi-color offset printing machine for sheet-fed offset printing. .
With the exception of a few excellent newspapers for coated paper printing, the vast majority of color newspapers, like black-and-white newspapers, use newsprint with good surface, porosity, ink absorption, and flexibility, and reel-assisted reeling mainly with osmotic drying and oxidative polymerization and drying. Paper web offset ink printing. Under the influence of the imprinting force, the ink penetrates quickly into the micropores of the newsprint. The fixing and drying of the ink are carried out almost at the same time. The ink after printing is adhered on the ink layer that is printed first and is already drying. From the ink drying point of view, the ink printing of color newspapers is a wet-press drying mode of dry printing, and the color sequence is the same as a single-color offset printing machine, and the flexibility is large.
Caibao uses porous, easily deformable, and low-white newsprint paper. It is difficult to register on high-speed web offset presses, and the color reproducibility is worse than that of GJ and coated paper. Therefore, Caibao is a general printing product. The national standard newspaper print quality requirements and test methods code number GB-14705-93 stipulates: The quality of color pictures should be basically in line with the natural tone, four-color overprint accuracy. Therefore, in addition to considering the overprinting effect of ink, the printing color sequence of a color newspaper must not meet the requirements for color reproduction of newspaper color pictures in the national standard. The following is a detailed analysis of color printing press color sequence.
A newspaper printing house uses Canadian newsprint and Tiens high-speed web offset printing ink to print color newspapers. The adhesive Tack values ​​for the four color inks of K, C, M, and Y are: 197, 148, 155, 219, respectively. The printing sequence according to the wet printing should be Y, K, M, and C. However, the Goss rotary offset press used in this plant is a parallel unit type. The paper feeding route is long and the overlay accuracy is relatively difficult to control. From the point of view of printing overprinting, yellow should not be placed on the first color printing, while yellow ink is highly adhesive and should not be placed on third and fourth color printing. The black ink is placed in the first color yellow ink master printing in the second color, is conducive to the printing of the magnetic standard. On the surface, black ink is less visible than yellow ink, and the overprint effect is poor. However, when the penetrating dry black ink and the ink-absorbing newsprint paper are in contact, the ink is immediately fixed and dried, and the adhesiveness rises sharply. When the yellow ink is overprinted, no ink stripping failure occurs. Therefore, the color sequences actually used in production are K, Y, M, and C.
The adhesive Tack of the four-color inks K, C, M, and Y of the rotary lithographic offset printing system of Shanxi Gao's Rollei are: 192, 186, 195, 198. All kinds of inks have little difference in adhesion, and the color sequence is not affected by adhesion. Printing using this ink mainly depends on the structure and color reproduction of the printing press to select the printing sequence. If a Gaussian-style web offset press is used, the paper-drawing line is short and the registration is easy. The color sequence of C, M, Y, and K is used, which is earlier than the print registration and does not make the ink use larger. The dark ink of the black ink has a failure of ink stringing, and the color reproducibility is good.
Coated paper has a layer of paint on the surface. It penetrates smaller than newsprint paper. In order to dry and dry web-fed offset inks, it dries more slowly on copper than newsprint. Therefore, when printing on color paper with coated paper, the printing sequence should be Follow the pattern of wet printing ink overprinting. Once there was a newspaper printing house using Gaussian full-satellite web offset printing presses and 85g/m square copper printing China Computer News. The printing color sequences used were C, M, K, and Y. In the printing process, black ink sticks on the yellow plate, but the yellow ink does not transfer to the paper. Finding the cause of the problem, they measured the adhesiveness of the four-color ink and used a domestic YQM-IB viscosity meter. The Tack values ​​of Y, M, C, and K inks are 6.05, 6.75, 7.85, and 4.37, respectively. After adjusting the printing sequence to C, M, Y, and K, the ink transfer is normal and the overprinting effect is good.
Mugs And Cups ,Custom Pottery Mugs,Handmade Pottery Coffee Mugs,Ceramic Coffee Cup
GlazeKing Ceramics TechnologyCo.,Ltd. , https://www.maglazekingceramics.com