CN117301697A

CN117301697A - Method for improving printing quality of intaglio printing press

Info

Publication number: CN117301697A
Application number: CN202210715979.5A
Authority: CN
Inventors: 梁诗文
Original assignee: CHIH SHAN INDUSTRY CORP
Current assignee: CHIH SHAN INDUSTRY CORP
Priority date: 2022-06-22
Filing date: 2022-06-22
Publication date: 2023-12-29

Abstract

The invention relates to a method for improving the printing quality of a gravure printing machine, when a gravure cylinder runs, a first filling part fills ink in a base into gravure dots by a second scraper to form first ink filling, then a third scraper is used for filling the ink in the base into the gravure dots to form second ink filling, and air bubbles generated during the first ink filling are extruded; and finally, the first scraper scrapes off redundant ink attached to the surface of the gravure cylinder along the rotation direction of the gravure cylinder, and as the ink in the gravure dots is full, the color of a printed matter is attractive, and meanwhile, the temperature of the ink is maintained by the constant temperature device, so that the ink is kept in a stable state, and the printing quality is improved.

Description

Method for improving printing quality of intaglio printing press

Technical Field

The invention relates to the technical field of intaglio printing, in particular to a method for improving the printing quality of an intaglio printing machine.

Background

Gravure printing is a printing method in which ink is filled into a depressed intaglio. The gravure printing can present fine layering and rich ink, and is very suitable for printing products to be printed. Meanwhile, the ink is dried rapidly after printing, so that the ink is also suitable for printing a huge number of printed matters such as color magazines, photos, wallpaper, propaganda, paper towels, watermarks, banknotes, decorative building materials and the like.

As shown in fig. 1, which shows the structure of a conventional intaglio printing press, an ink tank 40 is provided at the lowest part, a gravure cylinder 10 (plate roller) is provided in the middle, a blanket cylinder 20 (pressure roller) is provided above, and a printing object 30 is provided between the gravure cylinder 10 and the blanket cylinder 20; the ink tank 40 has printing ink therein; a doctor device 50 for scraping off excessive ink is arranged on one side of the gravure cylinder 10; in use, the above-mentioned intaglio cylinder 10 is filled with printing ink in the ink tank 40, excess printing ink on the surface of the intaglio cylinder 10 is scraped off by the doctor device 50, and the object 30 to be printed is pressurized by the intaglio cylinder 10 and the rubber cylinder 20, so that the printing ink is transferred from the portions of the intaglio dots 11 on the intaglio cylinder 10 to the object 30 to be printed.

However, the intaglio printing press as in fig. 1 has the disadvantage that:

1. the ink tank 40 is open, so that the solvent in the printing ink volatilizes, so that not only is the smell bad for human body, but also the printing ink is wasted further, and the cost is increased.

2. The conventional ink tank 40 is open, and when the gravure cylinder 10 is stained with ink, the printing ink is splashed along the centrifugal direction of the gravure cylinder 10, resulting in mess of the machine and the surrounding environment of the machine.

3. As shown in fig. 2, the region of the ink tank 40 is schematically indicated by immersing the intaglio cylinder 10 in the ink tank 40, then rolling the intaglio cylinder 10 counterclockwise to leave the ink tank 40, at this time, the intaglio dots 11 are filled with air bubbles C, then removing the ink on the intaglio cylinder 10 by the doctor device 50 at the upper end while pressing the ink into the intaglio dots 11, then transferring the ink onto the object to be printed 30, and then continuing to rotate back to the ink tank 40 and repeating the cycle; however, uneven filling of ink tends to occur, and bubbles C are formed in the dots 11 of the gravure cylinder 10, which results in poor quality and color of printed matter.

As shown in fig. 3, in order to solve the problems that the printing ink of the structure of fig. 1 and 2 is easily wasted and splashed everywhere, manufacturers develop a sealed doctor ink tank 60, the ink tank 40 used in fig. 1 is disposed at one side of the gravure cylinder 10, the upper and lower ends of the ink tank 40 are respectively provided with a first doctor 71 and a second doctor 72 which are symmetrical to each other and are adhered to the gravure cylinder 10, and the second doctor 72 below can prevent the printing ink from leaking; the design of fig. 3 does prevent the problem of printing ink evaporation and splash; however, it has the disadvantage that: the first doctor 71 and the second doctor 72 are fixed and cannot be adjusted, so that they must be closely adhered to each other for most gravure cylinder 10 applications, but as shown in fig. 4, the use of the closed doctor ink tank 60 can improve printing quality, however, air bubbles C remain in the gravure dot 11, so that there is a problem of air bubble holes or films in the center of the printed matter, that is, the ink filled in the gravure dot 11 is not sufficiently tight.

In fig. 3 and 4, the first doctor blade 71 is disposed in the reverse direction, so that the ink in the intaglio dots 11 is scraped off, and the printing quality is affected.

In addition, the inks for printing are susceptible to temperature changes, and for example, in high latitude areas or in cold hours, gravure printing is used, and it has been found that the fluidity (transfer effect) of the inks is less likely to affect the printing quality.

How to solve the problem that the printing quality of the prior gravure printing machine is not easy to control is a problem which is positively solved by related operators.

Disclosure of Invention

The invention mainly aims to provide equipment for improving the printing quality of an intaglio printing press, wherein a plurality of groups of scrapers are arranged in a closed ink tank, so that ink can be filled into intaglio dots in an intaglio cylinder, the printing ink quantity is full, and the printing quality is improved.

The invention aims to provide equipment for improving the printing quality of the intaglio printing press, wherein a constant temperature device is arranged in a closed type ink tank and is used for controlling the constant temperature of the ink in the closed type ink tank in a heat conduction mode, so that the ink can be kept at a good allocation rate for printing operation, the ink consumption cost can be reduced, and the health of staff in a factory can be protected.

Accordingly, the present invention provides a method of improving the print quality of an intaglio printing press, wherein:

the intaglio printing machine is provided with an intaglio cylinder and a rubber cylinder, and a printed matter is arranged between the intaglio cylinder and the rubber cylinder; the surface of the gravure cylinder is provided with a plurality of gravure dots, and the gravure cylinder is provided with a homodromous closed scraper device relative to one side of the rubber cylinder:

the same-direction closed scraper device is attached to the gravure cylinder and provides printing ink for the gravure cylinder, and comprises a base, a first scraper, a second scraper and an adjusting module;

the base is provided with the first scraper, the second scraper and the adjusting module, a hollow structure is arranged in the base for storing printing ink, and a plurality of pipelines are arranged in the base for supplying printing ink;

the first scraper is arranged at the upper end of the base, is contacted with the surface of the gravure cylinder and scrapes excessive ink on the gravure cylinder, wherein the arrangement direction of the first scraper is the same as the rotation direction of the gravure cylinder, and the first scraper is prevented from being reversely inserted into the gravure screen point of the gravure cylinder;

the second scraper is arranged at the lower end of the base, the second scraper is contacted with the surface of the lower end of the gravure cylinder, the second scraper scrapes dirt on the gravure cylinder, the second scraper is used for sealing the lower end of the base, so that printing ink is stored in the base and does not leak, and the arrangement positions of the first scraper and the second scraper are asymmetric;

the adjusting module is used for providing the first scraper group and finely adjusting the position of the adjusting module so as to adjust the relative position of the first scraper and the gravure cylinder; the first scraper scrapes redundant printing ink and fills the gravure dots with the ink, the second scraper seals the printed ink in the homodromous sealed scraper device by matching with the first scraper, and the adjusting module comprises a plurality of adjusting screws and an adjusting seat; the adjusting seat is arranged on the inner side of the base and is driven to move forwards and backwards by the adjusting screw; furthermore, the first scraper is arranged on the adjusting seat, and the relative position and angle of the first scraper and the gravure cylinder are adjusted by the position of the adjusting seat; the method is characterized in that:

the second scraper is arranged at the lower end of the base, the contact position of the second scraper and the gravure cylinder is a first filling part, a third scraper is arranged at the rear of the second scraper, and the contact position of the third scraper and the gravure cylinder is a second filling part;

the base is provided with a constant temperature device at the lower end of the adjusting module, the constant temperature device is used for keeping constant temperature of the stored ink from the outer side towards the direction of the base, the inner side of the base is provided with a temperature sensor, the constant temperature device and the temperature sensor are electrically connected with a temperature controller, and the constant temperature controller is used for controlling the constant temperature device to keep constant temperature;

when the gravure cylinder runs, the first filling part fills the ink in the base into the gravure dots to form first ink filling, then the second filling part fills the ink in the base into the gravure dots to form second ink filling, and air bubbles generated during the first ink filling are extruded; and finally, scraping off redundant ink attached to the surface of the intaglio cylinder by the first scraper along the rotation direction of the intaglio cylinder, extruding the ink into the plurality of intaglio dots, and extruding air of the intaglio dots.

In the method for improving the printing quality of the intaglio printing press, the first scraper is arranged at the upper end of the base in a manner that the inner angle is 50-60 degrees, and the second scraper is arranged at the lower end of the base in a manner that the inner angle is 30-40 degrees; and the third scraper is arranged at the upper end of the second scraper in an angle of 30-40 degrees.

Through the above-described structure and method, the present invention can provide the following advantages:

1. and the cleanliness of the working environment is maintained.

2. And the loss of printing ink is slowed down.

3. The printing effect is full and beautiful.

4. The solvent volatilization in the printing ink is reduced, the viscosity of the printing ink is stabilized, the ink proportion is stabilized, and further, the printed finished product can maintain good quality.

Drawings

Fig. 1 is a schematic diagram (one) of a conventional structure.

Fig. 2 is a schematic illustration of the intaglio mesh of fig. 1 filled with ink.

Fig. 3 is a schematic diagram (two) of a conventional structure.

Fig. 4 is a schematic illustration of the intaglio mesh of fig. 3 filled with ink.

Fig. 5 is a schematic structural view of the present invention.

Fig. 6 is a schematic view of the same direction closed scraper device.

Fig. 7 is a side structural view of fig. 5.

Fig. 8 is a timing diagram of the actual operation of the doctor apparatus and the gravure cylinder.

Fig. 9 is a flow chart of the use of the thermostat device of the present invention.

Reference numerals illustrate: 10-gravure cylinder; 11-intaglio dots; 20-rubber roller; 30-printed matter; 100-a closed scraper device in the same direction; 101-a base; 102-a first scraper; 103-a second scraper; 104-an adjustment module; 1041-adjusting screws; 1042-adjusting seat; 105-a third scraper; 106-oil seal; 200-a constant temperature device; 201—a temperature sensor; 202-a temperature controller; a-a first filling part; b-a second filling part; c-bubbles; 10-gravure cylinder; 11-intaglio dots; 20-rubber roller; 30-printed matter; 40-ink tank; 50-scraper means; 60-closed doctor ink tank; 71-a first scraper; 72-a second scraper; c-bubbles.

Detailed Description

For a further understanding and appreciation of the features and characteristics of the present invention, reference will now be made to the following preferred embodiments, taken in conjunction with the accompanying drawings, which are described below:

referring to fig. 5 and 7, the method for improving printing quality of a gravure printing machine of the present invention is installed on a gravure printing machine, wherein the gravure printing machine has a gravure cylinder 10 and a rubber cylinder 20, and a printed object 30 is disposed between the gravure cylinder 10 and the rubber cylinder 20; the surface of the gravure cylinder 10 is provided with a plurality of gravure dots 11, and the gravure cylinder 10 is provided with the same-direction closed doctor device 100 at one side opposite to the rubber cylinder 20.

As shown in fig. 5 and 7, the sealed doctor device 100 is attached to the gravure cylinder 10 to provide the gravure cylinder 10 with printing ink, the sealed doctor device 100 comprises a base 101, a first doctor 102, a second doctor 103, an adjusting module 104, a third doctor 105 and a constant temperature device 200, and an oil seal 106 is disposed on the sealed doctor device 100, and as shown in fig. 5 to 7, the oil seal 106 is disposed at the upper and lower ends of the sealed doctor device 100, the oil seal 106 on the upper side is disposed below the adjusting module 104, and the oil seal 106 on the lower side is disposed beside the third doctor 105, so that the printing ink can be prevented from leaking outside by the oil seal 106, and the clean and clean area can be maintained.

Referring to fig. 5 and 7, the base 101 is provided with the first scraper 102, the second scraper 103 and the adjusting module 104, and the inner side of the base 101 is a hollow structure for storing printing ink, and the base 101 is further provided with a plurality of pipelines for supplying printing ink; in addition, the two sides of the base 101 are provided with baffles, so that the ink can be prevented from leaking; the gravure cylinder 10 may additionally be cleaned.

As shown in fig. 5 and 7, the first scraper 102 is installed at the upper end of the base 101, and the first scraper 102 contacts with the surface of the gravure cylinder 10 and scrapes off the excessive ink on the gravure cylinder 10, wherein the first scraper 102 is arranged in the same direction as the rotation direction of the gravure cylinder 10, so as to prevent the first scraper 102 from being inserted into the gravure screen point 11 of the gravure cylinder 10, and the angle of the first scraper 102 is set to be 50 ° -60 ° forward and is set at the upper end of the base 101.

Referring to fig. 5 and 7, the second scraper 103 is disposed at the lower end of the base 101, the second scraper 103 contacts with the lower end surface of the gravure cylinder 10, the second scraper 103 scrapes dirt on the gravure cylinder 10, the second scraper 103 is used for sealing the lower end of the base 101, so that printing ink is stored in the base 101 and does not leak, the first scraper 102 and the second scraper 103 are disposed asymmetrically, which is different from the conventional structure of fig. 3, and the second scraper 103 is disposed at an angle of 30 ° -40 ° forward and is disposed at the lower end of the base 101.

As shown in fig. 5, 6 and 7, the adjusting module 104 includes a plurality of adjusting screws 1041 and an adjusting seat 1042; the adjusting seat 1042 is mounted on the inner side of the base 101, and the adjusting seat 1042 is driven by the adjusting screw 1041 to move forward and backward; as shown in fig. 6, the first doctor blade 102 is mounted on the adjusting seat 1042, and the relative position between the first doctor blade 102 and the gravure cylinder 101 and the relative angle between the first doctor blade 102 and the gravure cylinder 10 are adjusted by the position of the adjusting seat 1042.

As shown in fig. 5 and 7, the second scraper 103 is disposed at the lower end of the base 101, the contact position between the second scraper 103 and the gravure cylinder 10 is a first filling portion a, a third scraper 105 is disposed at the rear of the second scraper 103, the contact position between the third scraper 105 and the gravure cylinder 10 is a second filling portion B, in addition, the direction of the third scraper 105 is the same as the rotation direction of the gravure cylinder, and the angle of the third scraper 105 is 30 ° -40 ° and is set at the upper end of the second scraper 103.

As shown in fig. 5, 7 and 9, the thermostat 200 is disposed at the lower end of the adjustment module 104 of the base 101, the thermostat 200 heats or maintains temperature of the stored ink from the outside toward the base 101, a temperature sensor 201 is disposed at the inside of the base 101, the thermostat 200 and the temperature sensor 201 are electrically connected to a temperature controller 202, and the temperature controller 202 controls the thermostat 200 to perform a constant temperature control.

From the above description, the methods of use and the efficacy obtainable by the present invention are as follows:

1. referring to fig. 8, which shows a timing chart of operation of the gravure cylinder 10, the first doctor 102, the second doctor 103 and the third doctor 105, when the gravure cylinder 10 is operated, as shown in the drawing, the first filling portion a (i.e. the position contacting the gravure cylinder 10 and the second doctor 103) fills the ink in the base 101 into the gravure dot 11 to form a first ink filling, and then the second filling portion B (i.e. the position contacting the gravure cylinder 10 and the third doctor 105) fills the ink in the base 101 into the gravure dot 11 to form a second ink filling, and extrudes air bubbles generated during the first ink filling; finally, the first doctor 102 scrapes the excessive ink attached to the surface of the gravure cylinder 10 along the rotation direction of the gravure cylinder 10, the ink squeezes into the plurality of gravure dots 11, and the air of the gravure dots 11 is squeezed out, so that the color of the printed matter can be attractive due to the full ink in the plurality of gravure dots 11. In addition, the first doctor 102 can be adjusted in angle according to different intaglio cylinders 10, so that the ink can fill the intaglio dots 11.

2. As shown in fig. 9, a user can set the ink temperature by the temperature controller 202, then detect the ink temperature by the temperature sensor 201 disposed on the inner side of the base 101, and when the ink temperature is lower than the set temperature, the constant temperature device 200 heats the ink in the base 101 by heat conduction (indirect heating); if the ink temperature is too high, the ink temperature is lowered by the thermostat 200, so that the ink is not deteriorated by direct heating, and the ink can maintain the original fluidity and stability, thereby improving the printing quality.

3. As shown in fig. 5 and 8, in order to prevent the second doctor blade 103 and the third doctor blade 105 from being inserted into the intaglio dots 11, the second doctor blade 103 and the third doctor blade 105 form an angle of 133 ° with the bottom surface of the base 101, so that the ink can be filled into the first filling portion a and the second filling portion B.

The above description is illustrative of the invention and is not to be construed as limiting, and it will be understood by those skilled in the art that many modifications, variations or equivalents may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method of improving the print quality of an intaglio printing press, wherein:

2. The method of improving printing quality of a gravure printing machine according to claim 1, wherein the first doctor blade is disposed at an angle of 50 ° -60 ° at the upper end of the base, and the second doctor blade is disposed at an angle of 30 ° -40 ° at the lower end of the base; and the third scraper is arranged at the upper end of the second scraper in an angle of 30-40 degrees.