Carton pre-print cutting problem solving

The structure of the pre-print cutting system is composed of a high-speed color tracking system and a high-precision computer cutting system. The cutting accuracy of the computerized cross cutting system must be within 1 mm of the soil, so as to ensure the high precision of the preprinted cutting paper. High-speed color tracking systems require fast response times and precise detection ranges. At present, the diameter of the detection point is 0.3mm-1mm, and the detection distance is 30mm-100mm. Moreover, the color mark detector can adapt to the environment of cardboard production workshop, and it can be waterproof, dustproof, collision-proof and high-temperature resistant.

Preprinted color printing requirements

The printing of the color standard requires that the color of the color mark has a significant hue difference from the background color. The smaller the detection range of the color scale is, the more accurate the detection accuracy will be. However, if the color scale is too small, the sensing range of the color scale detector will become smaller. Therefore, the printing of the color standard requires that the color scale be fine, and at the same time, the minimum detection range of the detector should be ensured. If the length and width of the color mark is 20mm X 5mm, the cutting range is within 5mm. If the color mark can be printed smaller, such as 10mm X 2mm, the cutting accuracy can be increased to ± 1mm. In order to prevent the color mark from being printed too shortly, the left and right lateral movements in the cardboard production are beyond the detection range of the detector, resulting in a phenomenon that the color mark tracking system cannot sense, and it is necessary to add left and right automatic correcting devices on the color mark tracking system.

Pre-print cutting preparation and process requirements

Because of the pre-printed pattern, it must be dried after the hot plate is hot and high pressure. In this process, in order to avoid damage to the printed pattern by the hot plate, special requirements must be made on the ink, that is, the ink used must be able to withstand high temperatures and have good wear resistance. In the printing process, the paper roll is in the form of front-end and back-end, and it is difficult for the paper roll to maintain the original roll paper strength before the paper is delivered, but the paper roll must also be neat and compact.

Frequently Asked Questions in Production

The pre-printed face paper is not rewound due to uneven rolling, causing the cardboard paper to wrinkle. The base paper is loose during the unwinding process, and the original paper holder tension is uniform tension, which results in no tension on the tissue paper and heat entry. After the board, the tissue will wrinkle. This problem can be solved if a tension equalizing device is added to the paper feed position.

Pre-printed images appear to shrink after passing through the hot plate

The moisture content of the paper roll is heavy before printing. After printing, the water content will increase. After entering the hot plate, the water will evaporate, and the paper will shrink, so the printed image will also become smaller. . In order to reduce the moisture content of the base paper, the pre-printed base paper must be preheated.

Preprinted cardboard often shows slippage in hot plates

The surface of the pre-printed paper is usually smoother than the effect, and the ink will also generate oil volatilization during the preheating process, so that the cardboard easily adheres to the surface of the hot plate when passing through the preheating plate, resulting in great resistance. Therefore, the ink must be of a high-temperature, high-speed type. In order to increase the coefficient of friction of the surface of the tissue, the coating oil must not be too thick. When the board first enters the hot plate, the pressure of the hot plate should not be adjusted too tightly, and the temperature of the hot plate should be lowered slowly when the board is completely in. If necessary, add a water spray device to the top of the cotton belt.

Pre-printed cardboard cuts appear slanted

The preprinted paperboard is not adjusted to a large pressure on the hot plate, so the phenomenon of swinging to the left or right appears after the paper is ejected, so that a deviation occurs when the paper is cut at the cutter. To eliminate this swing, you can add a pressure wheel or increase the longitudinal correction device at the paper exit.

(Author: Deng Junbo Dongguan Qatar Computer Co., Ltd.)