Recently, the company uses a certain brand of offset printing machine for printing when a group of aviation with a snack, due to insufficient amount of powder, leading to the back of offset printed materials produced. Below, the author will talk about the control method of the amount of powder spray on the offset press for such problems.
The control of the amount of powder spray should be based on the non-sticky surface of the printed product, and the set values ​​of the amount of powder sprayed by different prints are different. In addition, under the premise of not causing the sticky phenomenon on the back side of the printed product, the amount of powder spray should be adjusted as small as possible, which is beneficial to the smooth operation of the post-press processing such as laminating, polishing, and oiling, thereby reducing the processing difficulty. And the rate of scrap.
There are three kinds of drying methods for ordinary inks, namely, oxidized conjunctiva drying, osmotic drying and volatile drying, all of which take a certain period of time (generally 4 to 8 hours) to be completely dried. Therefore, special attention should be paid to avoid sticking during ordinary ink printing. The phenomenon occurs. Once the sticky phenomenon occurs, it should be adjusted in time to increase the amount of powder sprayed, and the paper can be smoothly lowered to achieve the delivery by adjusting the wind speed of the fan.
In addition, the author introduces a small trick to check the amount of powder sprayed, that is, the water roller of the color group of the dark (such as black) ink is lifted, the remaining color groups are kept under pressure, and the dark color group is separately pressed. Full version printing. Since the dusting particles are white, the amount of powder sprayed can be clearly seen, and it is also possible to check whether there is clogging at the powder discharging port. When printing four-color newspapers and magazines, you can also use this method to check whether the blanket of the text printing color group is crushed, so as to avoid text defects.
The above content is selected from Keyin Media. Printing technology packaging and decoration" 2012/09 , more journal content please pay attention to the journal channel, the latest journal content click to enter the Ke Yin network electronic journal channel.
Food Packaging is the enclosing of food to protect it from damage, contamination, spoilage, pest attacks, and tampering, during transport, storage, and retail sale. The package is often labeled with information such as amount of the contents, ingredients, nutritional content, cooking instructions (if relevant), and shelf life. The package needs to be designed and selected in such a manner that there are no adverse interactions between it and the food. Packaging types include bags, bottles, cans, cartons, and trays.
Protection/preservation
Food packaging can retard product deterioration, retain the beneficial effects of processing, extend shelf-life, and maintain or increase the quality and safety of food. In doing so, packaging provides protection from 3 major classes of external influences: chemical, biological, and physical.
Chemical protection minimizes compositional changes triggered by environmental influences such as exposure to gases (typically oxygen), moisture (gain or loss), or light (visible, infrared, or ultraviolet). Many different packaging materials can provide a chemical barrier. Glass and metals provide a nearly absolute barrier to chemical and other environmental agents, but few packages are purely glass or metal since closure devices are added to facilitate both filling and emptying. Closure devices may contain materials that allow minimal levels of permeability. For example, plastic caps have some permeability to gases and vapors, as do the gasket materials used in caps to facilitate closure and in metal can lids to allow sealing after filling. Plastic packaging offers a large range of barrier properties but is generally more permeable than glass or metal.
Environmental issues: To protect the environment, we must be willing to reuse or recycle the packaging or reduce the size of the packaging.
Package safety: Before using a particular type of package for food, researchers must ensure that it is safe to use that packaging for the food being considered, and that there are no adverse interactions between the package and the food. This includes any metal contamination issues from a can to the food product or any plastic contamination from a bottle to the food product.
Product access: The packaging must be such that the product is readily accessible when the consumer is ready to use it. For example, pour spouts on milk cartons can make it easy to dispense the milk.
Food Packaging
Chocolate Box,Cake Box,Wine Box,Wine Box,Candy Box
ANSHAN JIASHUN ARTS AND CRAFTS CO.,LTD , https://www.jhwls.com