CN117325561A

CN117325561A - Offset printing color visualization and data control method

Info

Publication number: CN117325561A
Application number: CN202310879603.2A
Authority: CN
Inventors: 唐俊辉
Original assignee: Shenzhen Fuweizhi Printing Co ltd
Current assignee: Shenzhen Fuweizhi Printing Co ltd
Priority date: 2023-07-18
Filing date: 2023-07-18
Publication date: 2024-01-02

Abstract

The invention discloses a lithographic offset printing color visualization and data control method, which comprises the following steps: (1) The hue deviation is visually judged according to a brand-new color band, wherein the brand-new color band comprises four-color single-color solid, two-color overprinting color solid, three-color overprinting gray solid, 25%, 50%, 75% of dots of four-color single colors, 2%, 5%, 95%, 98% of dots, 25%, 50%, 75% of dots of Huang Pinqing three-color overprinting and 2%, 5%, 95% and 98% of dots. The method has the advantages that 2%, 5%, 95% and 98% of dots are further measured, so that the loss of the bright dot and the union of the dark dot are conveniently checked, meanwhile, the black dot gray with the same dot size and the three-color dot gray are arranged together, the deviation of the gray balance color hue is conveniently and rapidly compared, the data obtained by scanning the color band through the track scanner are matched, the hue deviation is rapidly and accurately adjusted, the color reduction quality of offset lithographic printing is effectively improved, and convenience is brought to the printing production operation.

Description

Offset printing color visualization and data control method

Technical Field

The invention relates to the printing field technology, in particular to a lithographic offset printing color visualization and data control method.

Background

Offset printing is a type of lithographic printing, and is simply called offset printing, which is a printing mode in which images and texts on a printing plate are transferred to a printing stock by means of a rubber blanket, and is called a printing mode in which the existence of the rubber blanket is the same. The blanket plays an irreplaceable role in printing, such as: the printing ink can well make up the unevenness of the surface of a printing material, fully transfer the printing ink, reduce the transfer of water on a printing plate (after the water plays a role in printing) to the printing material, and the like. The above is also merely a general concept, and we now refer to offset printing in general to a narrower range, namely a lithographic printing method with three cylinders (plate, blanket, impression), which is called koku printing in the south of our country.

Currently, the conventional color bands used for color control of offset lithographic printing press mainly comprise four-color single-color solid, two-color overprint color solid, three-color overprint gray solid, and 25%, 50%, 75% of dots of four-color single-color and 25%, 50%, 75% of dots of three-color Huang Pinqing overprint color, and specifically, the conventional color bands are composed of the following color blocks arranged in sequence: C. m, Y, M25, Y75, K, C, M, Y, M50, Y50, K, C, M, Y, M75, Y25, K, C, M, Y, K75, C25, K, C, M, Y, C50, K50, K, C, M, Y, K25, C75, K, C, M, Y, CMY, P, K, C, M, Y, CMY25, MY, K, C, M, Y, CMY50, CY, K, C, M, Y, CMY, CM, K; wherein Y represents yellow, M represents magenta, C represents cyan, K represents black, and the number represents a percentage of the color component; and, the three-color gray means: a grey color consisting of three colors C, M, Y; the field refers to: the color component is 100%, and no net point exists; dots refer to: the color component is less than 100% and more than 0%, and the existence of dots and white paper refer to: the dot component is 0%, and no dot exists.

However, the setting of the conventional color ribbon has no control points for the loss and the color shift of the brightness adjustment details below 25% and the union and the color shift of the dark adjustment above 75%, so that the machine operators cannot quickly and intuitively find the color changes of the two areas, the deviation cannot be adjusted in time, the color quality of offset lithographic printing is seriously affected, and the inconvenience is brought to production operation.

Disclosure of Invention

In view of the above, the present invention aims at overcoming the drawbacks of the prior art, and its primary objective is to provide a method for visual and data control of offset printing colors, which can effectively solve the problem that the operator of the machine cannot quickly and intuitively find the color changes of the above two areas due to unreasonable setting of the conventional color bands, so that the deviation cannot be adjusted in time.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

a lithographic offset color visualization and data control method comprises the following steps:

(1) The hue deviation is visually judged according to a brand-new color band, wherein the brand-new color band comprises four-color single-color fields, two-color overprinting color fields, three-color overprinting gray fields, 25%, 50%, 75% of dots of four-color single colors, 2%, 5%, 95%, 98% of dots, 25%, 50%, 75% of dots of Huang Pinqing three-color overprinting and 2%, 5%, 95%, 98% of dots, and black dot gray with the same dot size and three-color dot gray are arranged together;

(2) If the deviation is visually found, the density data obtained by scanning the color bar by the track scanner is visually observed to visually see the amount of addition and subtraction required for each ink, and the ink addition is performed according to the data, thereby adjusting the hue deviation.

As a preferable scheme, the brand new color ribbon is composed of the following color blocks which are sequentially arranged: y100, Y75, Y50, Y25, M100, M75, M50, M25, C100, C75, C50, C25, C100M100, C75M75, C50M50, C25M25, C100Y100, C75Y75, C50Y50, C25Y25, M100Y100, M75Y75, M50Y50, M25Y25, C100M100Y100, K100, C95M93Y93, K95, C75M66Y66, K75, C50M40Y40, K50, C25M19Y19, K25, C5M4Y4, K5, C2M1Y1, K2, 0, wherein Y represents yellow, M represents magenta, C represents cyan, K represents black, and the numbers represent percentages of color components; and, the three-color gray means: a grey color consisting of three colors C, M, Y; the field refers to: the color component is 100%, and no net point exists; dots refer to: color components less than 100% and greater than 0%, dots are present; paper white refers to: the dot component is 0%, and no dot exists.

Compared with the prior art, the invention has obvious advantages and beneficial effects, and in particular, the technical scheme can be as follows:

the method has the advantages that 2%, 5%, 95% and 98% of dots are further measured, so that the loss of the bright dot and the union of the dark dot are conveniently checked, meanwhile, the black dot gray with the same dot size and the three-color dot gray are arranged together, the deviation of the gray balance color hue is conveniently and rapidly compared, the data obtained by scanning the color band through the track scanner are matched, the hue deviation is rapidly and accurately adjusted, the color reduction quality of offset lithographic printing is effectively improved, and convenience is brought to the printing production operation.

Drawings

FIG. 1 is a schematic diagram of a conventional ribbon;

FIG. 2 is an image schematic of a conventional offset lithographic color;

FIG. 3 is a schematic diagram of a brand new color ribbon according to a preferred embodiment of the present invention;

FIG. 4 is a schematic image of a lithographic offset color according to a preferred embodiment of the present invention.

Detailed Description

The invention discloses a lithographic offset printing color visualization and data control method, which comprises the following steps:

(1) The hue deviation is visually judged according to the brand-new color band, as shown in fig. 3, the brand-new color band comprises four-color single-color solid, two-color overprinting color solid, three-color overprinting gray solid, 25%, 50%, 75% of dots of four-color single colors, 2%, 5%, 95%, 98% of dots, 25%, 50%, 75% of dots of Huang Pinqing three-color overprinting, and 2%, 5%, 95%, 98% of dots, and black dot gray with the same dot size is arranged together with three-color dot gray. Specifically, the brand new color ribbon is composed of the following color blocks which are sequentially arranged: y100, Y75, Y50, Y25, M100, M75, M50, M25, C100, C75, C50, C25, C100M100, C75M75, C50M50, C25M25, C100Y100, C75Y75, C50Y50, C25Y25, M100Y100, M75Y75, M50Y50, M25Y25, C100M100Y100, K100, C95M93Y93, K95, C75M66Y66, K75, C50M40Y40, K50, C25M19Y19, K25, C5M4Y4, K5, C2M1Y1, K2, 0, wherein Y represents yellow, M represents magenta, C represents cyan, K represents black, and the numbers represent percentages of color components; and, the three-color gray means: a grey color consisting of three colors C, M, Y; the field refers to: the color component is 100%, and no net point exists; dots refer to: color components less than 100% and greater than 0%, dots are present; paper white refers to: the dot component is 0%, and no dot exists.

(2) If the deviation is found visually, the density data obtained by scanning the color ribbon through the track scanner can visually see the amount of each ink to be added and subtracted, and ink addition is carried out according to the data, so that the hue deviation can be quickly and accurately adjusted. Specifically, during production of the printing machine, a sample is extracted, a track scanning instrument and corresponding software are used for measuring, the software automatically calculates a difference value according to target data to compare the sample, a machine operator is prompted to adjust printing colors, the machine operator executes corresponding operation according to prompts, the target data refer to the density of the printing ink, the corresponding value is the density of the printing tensor, the difference value is the difference calculated by the software, the system is proportional according to the difference calculation, and the operator is prompted to add or subtract, for example: when the black density is 1.72 and the actual measured density is 1.6, the system calculates that its difference is 0.12, i.e., the ratio to be increased is 7%.

The design focus of the invention is that: the method has the advantages that 2%, 5%, 95% and 98% of dots are further measured, so that the loss of the bright dot and the union of the dark dot are conveniently checked, meanwhile, the black dot gray with the same dot size and the three-color dot gray are arranged together, the deviation of the gray balance color hue is conveniently and rapidly compared, the data obtained by scanning the color band through the track scanner are matched, the hue deviation is rapidly and accurately adjusted, the color reduction quality of offset lithographic printing is effectively improved, and convenience is brought to the printing production operation.

The foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the technical scope of the present invention, so any minor modifications, equivalent changes and modifications made to the above embodiments according to the technical principles of the present invention are still within the scope of the technical solutions of the present invention.

Claims

1. A lithographic offset printing color visualization and data control method is characterized in that: the method comprises the following steps:

2. The offset lithographic color visualization and data control method of claim 1, wherein: the brand new color band is composed of the following color blocks which are sequentially arranged: y100, Y75, Y50, Y25, M100, M75, M50, M25, C100, C75, C50, C25, C100M100, C75M75, C50M50, C25M25, C100Y100, C75Y75, C50Y50, C25Y25, M100Y100, M75Y75, M50Y50, M25Y25, C100M100Y100, K100, C95M93Y93, K95, C75M66Y66, K75, C50M40Y40, K50, C25M19Y19, K25, C5M4Y4, K5, C2M1Y1, K2, 0, wherein Y represents yellow, M represents magenta, C represents cyan, K represents black, and the numbers represent percentages of color components; and, the three-color gray means: a grey color consisting of three colors C, M, Y; the field refers to: the color component is 100%, and no net point exists; dots refer to: color components less than 100% and greater than 0%, dots are present; paper white refers to: the dot component is 0%, and no dot exists.