Everyone must have a little understanding of the releva […]
Everyone must have a little understanding of the relevant knowledge of packaging and printing. Now the experts introduce you to the problems and solutions of the packaging process. details as follows:
The delamination phenomenon occurs in the packaged products, mainly because the strength of the adhesive is not enough. It is recommended to use some regular manufacturers' products, which can ensure the strength, reduce the humidity, increase the stiffness, and improve the quality and grade of the packaged products.
Nowadays, the types of glue used in domestic use (corrugated and confronted) are more chaotic. There are two types of combinations:
1. Oxidized starch and water glass glue. These kinds of glue are cheap and have certain viscosity. Therefore, they are still used in some low-end packaging and low-cost manufacturers. However, because such glue has strong alkalinity, sometimes the packaging will be Yellowing, softening, moisture absorption, and brittleness appear, which affects the printing quality of the ink. It occurs in various types of failures on the printing surface, so it belongs to the low-grade viscose that should be eliminated.
2. Polyvinyl acetate emulsion modified glue, this kind of glue is environmentally friendly adhesive, with high bonding strength and fast drying. It is widely used at present, but the price is relatively high, among which it is also high, medium and low. In general, the higher the price, the greater the strength, the smaller the water content, and the high-grade packaging products generally use such high-quality glue.
In the actual processing and production process, there are generally the following quality problems common to the process:
1. The product has a warp angle phenomenon. The main reason for this is that there are too many sheets attached, and the glue on the edge of the cardboard is dry and cannot be stuck. Therefore, it is usually appropriate to press 20 sheets.
2. The humidity of the product is too large, especially for the flat card of the gold card. Mainly due to the poor penetration and dissipative ability of gold cardboard, and the common flat glue has a higher water content. Therefore, it is usually solved by using quick-drying glue or drying the product in the sun.
3. If the product is tiled or flat, if it is placed in a place with a high air humidity, it will turn yellow for a long time. Mainly because some manufacturers use a large amount of water glass glue or starch glue. Therefore, in order to ensure the quality of the products, we should use better quality flat and corrugated glue.
4. The delamination phenomenon occurs in the packaged product, mainly because the strength of the adhesive is not enough. It is recommended to use some regular manufacturers' products, which can ensure the strength, reduce the humidity, increase the stiffness, and improve the quality and grade of the package. .