CN110978745A

CN110978745A - Gravure printing roller and set engraving process thereof

Info

Publication number: CN110978745A
Application number: CN202010019947.2A
Authority: CN
Inventors: 朱建鹏; 黄新建
Original assignee: Qingdao Yuncheng Plate Making Co ltd; Qingdao Leigh Mardon Packing Co ltd
Current assignee: Qingdao Yuncheng Plate Making Co ltd; Qingdao Leigh Mardon Packing Co ltd
Priority date: 2020-01-09
Filing date: 2020-01-09
Publication date: 2020-04-10
Anticipated expiration: 2040-01-09
Also published as: CN110978745B

Abstract

The invention discloses a gravure printing roller and a sleeving and engraving process thereof, which comprise a cylindrical printing roller base body, wherein a copper layer is plated on the cylindrical surface of the printing roller base body, and a mesh opening is engraved on the copper layer and is formed by combining a plurality of rows of engraving grooves which are sequentially and axially arranged from the cylindrical surface of the printing roller base body. The invention has the beneficial effects that: after the first notch and the second notch are added, the image-text edge mesh points are dense and full compared with the front part, the conventional mesh point group of the third notch is intersected and superposed with the mesh points of the second notch to cause the enlargement of the mesh points, and when a scraper passes through the screen, the mesh points are filled with ink, so that the ink is normally scraped downwards. Firstly, filling the first notch and the second notch which are added with ink, then filling the conventional mesh group with ink, enabling the scraper to be in contact with the plate roller from the front of the first notch, enabling the initial contact position of the scraper and the plate roller to be advanced, filling and scraping the first notch, the second notch and the conventional mesh group with the ink, ensuring that the ink in the mesh at the boundary of the plate roller is sufficient, and ensuring the quality of a printed product.

Description

Gravure printing roller and set engraving process thereof

Technical Field

The invention belongs to the field of processing of printing plate rollers of printing machines, and particularly relates to a gravure plate roller and a sleeve carving process thereof.

Background

In the field of gravure printing, printing is generally performed using a gravure roll. On the gravure roll, a mesh needs to be engraved for storing ink. And a net hole wall is formed between the adjacent net holes. The scraper scrapes off redundant ink on the surface of the screen hole wall after passing through the screen hole, so that the ink in the screen hole is full, the ink is not enough at the initial contact part of the scraper and the printing roller, namely the boundary of the printing roller, and the ink is directly scraped off by the scraper, and in the downward running process of the scraper, part of the ink in the screen hole is easily taken away, so that the ink in the screen hole is not enough, and the printing quality is influenced.

Patent document CN202608281U discloses an ultra-fine gravure printing roller, which comprises a printing roller body, wherein the printing roller body comprises a cylindrical printing roller base body, a copper layer is plated on the cylindrical surface of the printing roller base body, and a mesh hole is engraved on the copper layer and is formed by combining a plurality of engraving grooves; and a plurality of engraving grooves of the same net hole are sequentially arranged along the axial direction of the plate roller body, and the side surfaces of two adjacent engraving grooves are communicated. The net hole is formed by combining three, five or nine carving grooves. In the intaglio roller, the number of engraved grooves in the cells is increased, so that the cells have larger volume, and the printed patterns have high ink content, thereby being beneficial to forming high-precision pictures and texts in printing. However, at the initial contact part of the scraper and the plate roller, the scraper still takes away the ink in the mesh after the ink scraping operation, and the phenomenon of insufficient ink exists.

Patent document CN109030494A discloses a method for detecting the quality of cells of a cylinder for laser engraving gravure printing plate based on machine vision, which improves the detection efficiency and detection precision by image acquisition, image digital processing, cell deformation detection and cell quality discrimination, finds problems in the plate making process in time, effectively improves the yield of gravure plates, and helps to improve the process flow. The detection method only detects the quality of the mesh after conventional laser engraving, does not detect the ink bearing effect of the mesh, and does not detect the volume of the ink in the mesh after the ink scraping operation of the scraper.

Patent document CN208304160U discloses an efficient gravure roller engraving device, open fiber laser 26 adjust knob, process the sculpture to gravure roller 18, after the sculpture is accomplished at last, open condenser switch 31 and cool off gravure roller 18 in time, through being provided with two at least fiber laser 26, can carve different layout areas simultaneously, compared with the prior art, the time that engraves the version roller required significantly reduces, thereby plate-making efficiency has been improved greatly, through being provided with conveyer 36, driving motor and pivot 14 isotructures, make gravure roller 18 can roll the sculpture, and fiber laser 26 is portable to be carved, make whole sculpture area more comprehensive. Similarly, the ink in the mesh can be still taken away after the ink scraping operation is carried out on the initial contact part of the scraper and the printing roller by the mesh carved by the device, and the phenomenon of insufficient ink exists.

Disclosure of Invention

The invention aims to overcome the technical defects and provides a gravure roller and a sleeve engraving process thereof.

The technical scheme adopted by the invention for solving the technical problem is as follows: the gravure printing roller comprises a cylindrical printing roller base body, wherein a copper layer is plated on the cylindrical surface of the printing roller base body, and a mesh opening is carved on the copper layer and is formed by combining a plurality of rows of carving grooves, and the carving grooves are sequentially and axially arranged on the cylindrical surface of the printing roller base body.

Preferably, the engraved groove includes a first notch, a second notch, and a third notch whose notch areas are sequentially increased.

Preferably, the density of the first notch, the second notch and the third notch is reduced in sequence, and the depth is unchanged.

Preferably, the third slot openings are communicated longitudinally, arranged in a transversely staggered mode and spaced out of the mesh wall; gaps are formed in front of the mesh wall close to one end of the plate roller substrate, second notches are uniformly arranged in the gaps, and first notches are arranged between every two adjacent second notches.

Preferably, the first notch comprises two rows of notches arranged on the front side and the rear side of the second notch, and the two rows of notches are communicated with each other.

Preferably, the first notch is communicated with the second notch, and the first notch and the second notch are both communicated with the third notch.

Preferably, the first notch, the second notch and the third notch are all conical structures with the ground facing upwards and the vertexes facing downwards.

The process for engraving the gravure roller comprises the following steps:

(1) producing a base roller with standard size, and putting the base roller into cleaning equipment for cleaning;

(2) according to the drawing of a printing roller used by a printing machine, carrying out cutting, flange welding, chamfering and grinding surface processing treatment on the base roller;

(3) washing the plate surface of the plate roller by using 3% dilute sulfuric acid to remove an oxide layer of the plate roller;

(4) washing the printing roller by using a metal detergent to remove oil stains on the surface of the printing roller;

(5) adopting a sulfate copper plating method, and then carrying out cutting by a turning and grinding combination machine or polishing by a grinding and polishing machine;

(6) scanning the drawing of the printing roller in the step (2), and using professional processing software to perform manufacturing processing on images, characters and gradient colors by combining the characteristics of gravure printing;

(7) engraving mesh holes: the engraving knife is moved to the cylindrical surface of the printing roller matrix,

a. in unit width, the carving tool is fed, paused and withdrawn, and 20 first notches are carved into a first row; the 15 first notches are in a third row;

b. the engraving knife moves leftwards, and 10 second notches are engraved to form a second row;

c. the engraving knife moves to the right, and 20 third notches are engraved to form a fourth row;

……

moving the engraving knife to the left end face of the printing roller matrix and stopping;

(8) plating chromium on the surface of the plate roller by an electroplating method, and performing the procedures of cleaning, degreasing, plating chromium and polishing.

The invention has the beneficial effects that: after the first notch and the second notch are added, the image-text edge mesh points are dense and full compared with the front part, the conventional mesh point group of the third notch is intersected and superposed with the mesh points of the second notch to cause the enlargement of the mesh points, and when a scraper passes through the screen, the mesh points are filled with ink, so that the ink is normally scraped downwards. Firstly, filling the first and second added notches with ink, then filling the conventional screen hole group with ink, and making the scraper contact with the screen hole from the front of the first notch, so that the initial contact position of the scraper and the screen hole is advanced, and the scraper carries the ink to fill and strickle off the first notch, the second notch and the conventional screen hole group, thereby ensuring that the ink in the screen hole at the border of the printing roller is sufficient and ensuring the quality of the printed product.

Drawings

FIG. 1 is a schematic diagram of the principle of ink-jet printing on a plate roll;

FIG. 2 is a schematic view of the cylindrical structure of the plate roller;

FIG. 3 is a schematic view of the roll deployment;

FIG. 4 is a schematic view of a doctor blade placed in front of a cell;

FIG. 5 is a snapshot of the engraver before cell modification;

FIG. 6 is a schematic view of the structure of FIG. 5;

FIG. 7 is a snapshot of the engraver after cell modification;

FIG. 8 is a schematic view of the structure of FIG. 7;

fig. 9 is a partially enlarged view of fig. 7.

Labeled as: 01. an ink tank; 02. printing roller unloading; 03. impressing the rubber roller; 04. a scraper;

05. a substrate; 1. a printing roller substrate; 2. carving grooves; 21. a first notch; 22. a second notch;

23. a third notch; 3. a net cave wall.

Detailed Description

The invention is further explained below with reference to the embodiments of the drawings.

As shown in fig. 1: on an intaglio printing press, a lower printing roller 02 is immersed into an ink tank 01 filled with ink, when the lower printing roller 02 rotates, the ink is driven to rotate clockwise and adhere to the lower printing roller 02, and a scraper 04 is positioned on one side of the lower printing roller 02 and above the ink tank 01 to scrape off the redundant ink on the lower printing roller 02, namely the ink is filled into a grid hole of the lower printing roller 02; the lower plate roller 02 and the impression rubber roller 03 work in a matching manner to complete printing on the printing stock 05.

As shown in fig. 2, 3, and 4: at the initial contact part of the scraper and the screen points, namely the boundary of the image-text screen points, the ink is directly scraped off by the scraper because the screen points have uneven edges and are not dense, and in the downward running process of the scraper, partial ink in the screen points is easily taken away, so that the ink in the screen points is insufficient, and the printing quality is influenced.

In this case, due to the existence of the cells as shown in fig. 5 and 6, it can be seen from the cell layout that a plurality of blanks appear at the left side boundary of the cell group, and these blanks cannot bear ink, and the scraper scrapes off the ink at the rear part in the rotation process of the plate roller, and when the scraper contacts with the cells, the amount of ink carried by the blank plate roller is very small, and the filling effect on the cells is not good.

The gravure printing roller comprises a cylindrical printing roller base body 1, wherein a copper layer is plated on the cylindrical surface of the printing roller base body 1, and a mesh opening is carved on the copper layer and is formed by combining a plurality of rows of carving grooves 2, and the carving grooves 2 are sequentially and axially arranged from the cylindrical surface of the printing roller base body; the carving groove 2 comprises a first notch 21, a second notch 22 and a third notch 23, wherein the notch areas of the first notch 21, the second notch 22 and the third notch 23 are sequentially increased; the density of the first notch 21, the second notch 22 and the third notch 23 is reduced in sequence, and the depth is unchanged; as shown in fig. 7, 8 and 9, the third slots 23 are longitudinally communicated, transversely staggered and spaced out of the cell walls 3; gaps are formed in front of the mesh wall 3 close to one end of the plate roller matrix 1, second notches 22 are uniformly arranged in the gaps, and first notches 21 are arranged between every two adjacent second notches 22. Therefore, after the first notch 21 and the second notch 22 are added in front of the third notch 23 which is a conventional screen hole group, the notches can bear ink, the initial contact position of the scraper and the plate roller is advanced to the front side of the first notch 21, which is equivalent to advancing the initial contact position of the scraper and the screen hole on the plate roller, and the screen holes on the edge of the image and text are dense and full; the ink is filled in the mesh holes in advance by the scraper, and in the process of continuing to rotate the printing roller, the third notch conventional mesh hole group and the second notch mesh hole are overlapped in an intersecting manner, so that the mesh holes are enlarged, and the carrying capacity of the ink is increased; the scraper fills the conventional cell group downwards, and when the scraper carries part of the ink in the first notch 21 and the second notch 22 to run downwards, the adhesion capability to the ink in the conventional cell group is reduced, even the ink in the conventional cell group is not adhered, so that the content of the ink in the conventional cell group, namely the third notch 23, is not influenced.

The first notch 21 includes two rows of notches arranged on both front and rear sides of the second notch 22, the two rows of notches communicating with each other. The first notch 21 is communicated with the second notch 22, and the first notch 21 and the second notch 22 are communicated with the third notch 23. The three notches are communicated with each other, so that the area of the ink attached to the screen holes is increased, and the filling of the ink in the conventional screen hole group is facilitated.

The first notch 21, the second notch 22 and the third notch 23 are all conical structures with the ground surface facing upwards and the vertex facing downwards. The structure is the shape carved by the needle head of the carving needle, and accords with the mesh shape of the carving needle after the conventional operation.

In order to realize the engraving of the intaglio roller, the engraving process adopted by the invention comprises the following steps:

……

Feeding the engraving knife in the step (7), namely cutting the engraving knife into the copper layer along the radial direction of the plate roller body; and the graver retracts, namely, the graver retracts along the radial direction of the plate roller body.

The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.

Claims

1. Gravure printing roller, including cylindric version roller base member one deck copper layer has been plated on the face of cylinder of version roller base member, and it has the cave to engrave on the copper layer, its characterized in that: the mesh point is formed by combining a plurality of rows of engraving grooves, and the engraving grooves are sequentially and axially arranged from the cylindrical surface of the printing roller base body.

2. The gravure roll according to claim 1, characterized in that: the carving groove comprises a first notch, a second notch and a third notch, wherein the notch areas of the first notch, the second notch and the third notch are sequentially increased.

3. The gravure roll according to claim 2, wherein: the net hole density of the first notch, the second notch and the third notch is reduced in sequence, and the depth is unchanged.

4. The gravure roll according to claim 3, wherein: the third groove openings are communicated longitudinally, are arranged in a transversely staggered mode and are separated out of the mesh wall; gaps are formed in front of the mesh wall close to one end of the plate roller substrate, second notches are uniformly arranged in the gaps, and first notches are arranged between every two adjacent second notches.

5. The gravure roll according to claim 4, wherein: the first notch comprises two rows of notches which are arranged at the front side and the rear side of the second notch, and the two rows of notches are mutually communicated.

6. The gravure roll according to claim 5, wherein: the first notch is communicated with the second notch, and the first notch and the second notch are communicated with the third notch.

7. The gravure roll according to claim 6, wherein: the first notch, the second notch and the third notch are all conical structures with the ground facing upwards and the top points facing downwards.

8. A process for engraving a gravure roll according to any one of claims 1 to 7, comprising the following steps:

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