Gravure printing and letterpress printing (2)

Laser engraved gravure and electron beam engraved gravure bring about increased cost of plate making due to the high cost of equipment. Although these two methods are carved out, the quality of the printing plate is very high. However, at present, it is still used in small quantities. The vast majority of gravure is still dominated by electronic engraving.
In order to ensure the quality of the electronic engraving gravure, the size and depth of the engraving net hole are specified in the industry standard. However, the size of the cell site and the depth and random type (products of different companies), the number of network lines, the age of the cutter, the angle of the cutter, the thickness of the copper layer (hardness of the copper layer is 180 to 210) and the product quality requirements Impact, more variable factors, industry standards, only 70 lines / cm, 130 ° knife angle and the new knife as an example.
Second, the gravure printing process gravure printing uses the park press garden rotation type direct printing method. Its characteristics are: the structure of the printing press is simple, the printing plate is resistant to the printing force, the printing speed is fast, the ink of the printed matter is thick, the layers are rich, and the cost is low when printing in large quantities. Gravure printing is classified in many ways and can be divided into three categories according to its purpose: book and gravure printing machines, flexible packaging gravure printing machines and hard-pack gravure printing machines. Books and gravure machines are used to print magazines, books and magazines, pictorials, etc., and are equipped with folding devices at the back; flexible packaging gravure machines are used to print packaging materials such as cellophane, plastic film, aluminum foil and paper, and can be equipped with composite, glazing, and molding. Cut the device. Plastics can be divided into two categories: sheet-fed gravure machines and web-fed gravure machines, most of which use web gravure machines. According to the printing color number classification, it can be divided into monochrome gravure printing machine and multi-color gravure printing machine. According to the arrangement of printing color group, it can be divided into a satellite gravure printing machine and a combined gravure printing machine. The satellite-type gravure printer shares several impression cylinders in several color groups. The combined gravure printing machine is horizontally arranged in each color group to form an assembly line. (See left picture)

Gravure printing, in accordance with the requirements of the work task list and proofs to receive ink, substrates; then install the printing cylinder; adjust the impression cylinder on the liner, so that the pressure on the various parts of the plate is consistent; and adjust the squeegee to India Edition angle and distance, power on the test. After the test proofs are qualified, they can be formally printed by signing the workshop supervisor and the customer. Here is a brief introduction to the printing process using a combination gravure printer as an example:
1. Unwinding Device and Adjustment 1) The Web Holder The Web Holder mounts the web or roll of plastic film on the press with a tapered tip. When the roll is nearly used up, the automatic take-up device places a new roll or plastic. The film roll automatically adheres to the running tape while cutting off the old tail and completing the roll change without stopping the machine.
2) tension automatic control system paper or film in the pre-press unwinding process, multi-color printing process or postpress printing process need to maintain a certain tension, tension is too easy to produce longitudinal wrinkles, tension is too small and easy to produce horizontal wrinkles In short, the fluctuation of tension will affect the accuracy of overprinting.
3) Paper tape lateral adjustment device In order to ensure that the lateral taper of the printing material tape when entering the printing part or rewinding is consistent, lateral adjustment is required. Lateral adjustment is either adjusted by a pneumatic (hydraulic) cylinder or adjusted by a lateral adjustment roller.
2. Squeegee and impression cylinder adjustment 1) The scraper adjusts the sum of the pressure required by the scraper to scrape off the ink on the surface of the printing plate and the pressure required to resist the impact force of the ink. The pressure is proportional to the printing speed, and the general speed is fast and the pressure is correspondingly large. In addition, the angle between the doctor blade and the printing plate is generally 30° to 70°. In this way, the knife edge can be maintained without damaging the plate surface, and the quality of the printed product can also be ideal.
2) Adjust the impression cylinder after adjusting the impression cylinder plate cylinder. For different substrates, the printing pressure of the impression cylinder is different. Example: Glass paper, plastic film, printing pressure of 1 ~ 5Pa. Copper plate paper, thin cardboard, printing pressure of 8 ~ 15Pa. The printing pressure of white paper and the like is 20 to 30 Pa.
3. Ink drying temperature adjustment Gravure inks are basically solvent-based inks. When printing, the operator should adjust the drying temperature of each unit according to the type of printing materials, printing speed, graphics area, ink layer thickness. Drying temperature is not too high, generally should be controlled below 80 °C, the highest should not exceed 100 °C. Otherwise it will cause the printing material to shrink, affect the registration, if the ink is too low, it will be dry. (To be continued)

Snacks Stand Up Pouches supplier Richest Pack, wholesale Popcorn Plastic Bag, Banana Chips Packaging, Potato Chips Bag , etc., packaging for various kinds of snacks. Like as popcorn, banana chips, potato chips, corn chips, dried squids, nuts, etc. According to the demand to choose the different material, size, color, thickness to protecting products.

Snacks Stand Up Pouches have good moisture proof, retain freshness, shading effect. With good quality, competitive price and best services.

Detailed Production Description:

Material usually divided into three types:

1) two layer materials composite;

2) Three layer materials composite;

3) Four layer materials composite; 

Thickness: 50 ~ 250 microns by customized

MOQ: 10,000 PCS

Samples: Free Samples

Logo: Accept Custom Logo

Feature:Moisture proof

Sealing &Handle:Zipper top

Place of Origin: Shenzhen, China

Surface Handling: Gravure Printing

Color: up to 9 colors or customer requirement

Usage: healthy food, salted food, instant soup, etc.

Payment Term: EXW, FOB, CIF

Delivery Time: 12 ~ 15 work days

Packaging: Bundles/Cartons

Port of Loading: Shenzhen or Hong Kong

Popcorn Plastic Bag

banana chips packaging

potato chips bag

Snacks Stand Up Pouches

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