Ten Differences in Gravure Printing Machines and Gravure Printing Machines for Composite Flexible Packaging

【Chinese Packaging Network News】Compared with other gravure printing machines such as gravure printing, the composite flexible packaging gravure printing machine has the following features.

1, due to the small thickness of the material, generally put / winding diameter is not large, so the structure can be more compact. Sometimes the take-up and take-up diameters can be very small (eg no more than 600 mm), the take-up reel can be on the same unit as the input section, and the output section can be on the same unit as the take-up reel.

Due to the small material thickness, only the lap joint method is adopted for the material tape transfer, and the butt joint method is not required.

2. The pretreatment device is different from the pretreatment device on the gravure printing machine. Because the adhesion of the film material is not as good as that of the paper material, the surface treatment of the material is one of the important factors for successful printing. Therefore, the following pretreatment system is often installed at the outlet of the unwinding section: corona treater and preheated roll. The pretreatment on paper gravure presses is usually dusting, flattening and temperature and humidity treatment (drum, single-sided and double-sided pretreatment boxes).

3, because most of them are extensible materials, so the overall machine tension is small, and the tension control system's accuracy, sensitivity, stability than the general paper gravure printing machine requirements are higher, especially the need to unwind parts and input parts are high The accuracy of the tension control system is such that the material band before entering the first printing unit is in a very stable state. At the same time, paper testing must use a larger floating roller.

4. Since most materials are extensible materials, the layout of the material transfer path should be more stringent (including the distance between the two embossing points, the tape wrap angle, etc.). Over-roller diameters are small. For gravure printers that may use aluminum foil, special consideration must be given to the construction of the transitional roller. Light rollers are usually required and the path is as short as possible.

5. Because the tension is small, the tape guide generally does not require the use of a hydraulic drive mechanism.

6. Since some flexible packaging materials are heat-sensitive materials, the design of the dry cooling system must pay special attention.

7. Because the surface is smooth and fine level reproduction is better, the electrostatic assisted ink transfer (ESA) system is generally not used. Although some gravure-pack gravure presses also install such devices, they are mainly aimed at special products and may be printed on paper.

8, because most of the material is a transparent film, so the tape guide generally do not use photoelectric sensors, but using pneumatic or ultrasonic sensors. For the same reason, registration plates, image viewer systems, etc. need to be equipped with reflectors.

9. Due to the smaller embossing force and tension, the width of the machine is generally larger than that of paper and cardboard gravure printing machines. The use of a sleeve type plate cylinder is more than that of a paper gravure printer.

10. As reverse printing and coating are more common, two-way unwinding/cross-docking carton printing units are common.