Gravure and Flexographic Printing
(1)Gravure Printing
Definition: a method of direct printing in which the ink contained in the pits of a gravure plate is embossed directly onto the substrate.
(2)Flexography
Definition: a method of printing in which an elastic letterpress plate is used to transfer ink to a substrate.
Gravure Printing Pictures
Flexo Printing Pictures (1) Fine text and lines should be designed as a single package to avoid inadmissible multi-color overprinting. The width of fine lines should not be less than 0.1mm, otherwise it is easy to lose or unclear strokes in printing. The net height of Chinese fonts is not less than 1.8mm, and the net height of English fonts is not less than 1.5mm.
(2) The anti-white text should be designed with special attention, if the text is small, especially when the strokes are thin, to use a single color. The choice of fonts should also pay attention to, round head body, black body, such as line body is a better choice, and Song body, the old Song body (horizontal thin vertical thick) and other strokes are too far apart from the font should be used with caution, such as the use of such fonts in the design, pay attention to the net height of the Chinese font is not less than 2.5mm, the net height of the English font is not less than 2mm. temperature printing composite flexible packaging materials to be made into a variety of bags can be used eventually. There are two ways to make bags, one is packaging using manufacturers to use roll film in automatic packaging machine filling, and molding and packaging to become a variety of bags; the other is due to the bag making machine made of a variety of bags and then fill the contents. As a result of the professional bag-making control precision, beautiful bag, bag-making changes, bag type, therefore, in quite a number of cases, are first made into bags. The main varieties of bags are: three-sided sealing bag (closed palm sealing bag), back sealing bag, folding gang (organ bag), upright bags, etc., as shown in the figure below.
Figure 1
Three-side-seal bag
Figure 2
Back-seal bag
Figure 3
Organic bag
Figure 4
Upright bag
Vacuum packaging is mainly used for the packaging of food products such as meats, cereals, processed foods and foods susceptible to oxidative degradation, but also can be used for mechanical parts, instruments and down products, wool products and other fluffy products packaging.
With the gradual improvement of people's living standards, as well as the continuous improvement of the quality of life requirements, vacuum packaging in contemporary people's lives has occupied an indispensable pivotal position, it is a typical field of vertical extension of packaging technology, plays an irreplaceable role. Vacuum packaging, simple and clear that its most important role is to remove oxygen, in order to help prevent food spoilage.
The principle of vacuum packaging is very simple. The main reason for the deterioration of food mold is caused by the activities of microorganisms, and microorganisms (such as molds and yeast) needs oxygen to survive, vacuum packaging is the use of this principle, the bag and the food cells within the oxygen pumped off, so that microorganisms lose the "survival of the environment". At the same time, this also prevents the food due to oxidation and make the food tasteless, spoilage, so as to achieve the effect of food storage and freshness for a longer period of time. The performance of food vacuum packaging materials, directly affecting the storage life of food and flavor changes. In the vacuum packaging, the choice of good packaging materials is the key to the success of the packaging.
Since we are talking about vacuum packaging materials, it is essential that the classification of materials, the following are suitable for vacuum packaging of the characteristics of each material:
One, which PE is suitable for low-temperature use, RCPP is suitable for high-temperature cooking to make;
Second, PA is to increase the physical strength, puncture-resistant performance;
Third, AL foil is to increase the barrier performance, light shading;
Third, AL aluminum foil is to increase the barrier performance, shading;
four, PET, to increase mechanical strength, quite excellent.
Then according to the demand, the combination, a variety of performance, there are also transparent, in order to increase the barrier performance using water-resistant PVA high barrier coating. Generally:
PA/PE or PA/RCPP
PET/PE or PET/RCPP
There are also three-layer, four-layer, in order to increase the material texture performance:
PET/PA/PE
PET/AL/RCPP
PA/AL/RCPP
PET/PA/ AL/RCPP High-temperature cooking bag, vacuum bag is used for packing all kinds of meat cooked food, easy to use and hygienic.
Material: NY/PE, NY/AL/RCPP, NY/PE
Features: moisture-proof, temperature-resistant, light-shielding, aroma-preserving, strong
Applications: high-temperature sterilized food, ham, curry, grilled eel, grilled fish and meat brine products.
Vacuum packaging is currently the most used mainly film materials, of course, there is also the use of bottles and cans. The film material used in the vacuum packaging of food, to ensure that its packaging effect on a variety of foods, aesthetic, economic and other aspects to achieve the best state. At the same time, food vacuum packaging on the material of light-blocking and stability also has high requirements. When a single material can not meet these requirements, packaging pieces will often be a combination of a variety of different materials. 1, high barrier: the use of different plastic materials with high barrier properties **** extrusion film, to achieve the effect of oxygen, water, carbon dioxide, odor and other high barrier.
2, stable performance: oil resistance, moisture resistance, low temperature freezing resistance, quality, freshness, odor, can be used for vacuum packaging, aseptic packaging, inflatable packaging.
3, low cost: relative to glass packaging, aluminum foil packaging and other plastic packaging, to achieve the same barrier effect, **** extrusion film has a greater advantage in cost. Due to the simple process, the production of film product costs and dry composite film and other composite films can be reduced by 10-20% compared to 4, flexible specifications: you can reach your different needs for different products.
5, high strength: **** extrusion film in the process has the characteristics of stretching, plastic stretching can be correspondingly increased strength, but also in the middle of the nylon, polyethylene and other plastic materials, so that it has more than the general plastic packaging composite strength, there is no delamination of the phenomenon of peeling, softness, good heat sealing performance is excellent.
6, capacity than small: **** extrusion film can be vacuum shrink packaging, capacity volume ratio of nearly 100%, which is glass, tin cans, paper packaging can not be compared.
7, non-polluting: no added binder, no residual solvent pollution problems, green.
Vacuum packaging bags moisture + anti-static + explosion + corrosion + insulation + energy saving + single perspective + UV + low cost + capacity than small + no pollution + high barrier effect. Vacuum packaging technology originated in the 40's, since the 50's plastic film successfully applied to commodity packaging, vacuum packaging technology has been rapid development. Packaging level to a certain extent reflects a country's level of science and technology and affluence. China's vacuum packaging technology research and application is still in its infancy.
One, in 1962, Ordal proposed impermeable film can inhibit the growth of pathogenic microorganisms, packaging fresh meat can extend its shelf life.
Second, Baltzer believes that vacuum-packed fresh meat than aerobically packaged fresh meat shelf life is longer for the following reasons:
(1) the total number of microorganisms in the anaerobic condition increases slowly;
(2) putrefaction and mucus is reduced;
(3) after storage, the final microbial population within the vacuum packaging than aerobic packaging is less. This indicates that the oxygen-impermeable film vacuum packaging of fresh meat, when the oxygen in it is converted to carbon dioxide, the oxygen-impermeable film can block the outside oxygen re-entry into the package, so the vacuum packaging can extend the shelf life of fresh meat.
Three, in 1970, Pierson and other vacuum packaging to create a microbial species and level of selection of the "ecosystem". 1974 SCOPA's first application of MAP (ModifiedAtmospherePackage, is a kind of). In 1974, SCOPA first applied MAP (ModifiedAtmospherePackage, is a kind of packaging first vacuum, and then filled with a certain proportion of mixed gas packaging) packaging meat products.
Four, Pesis et al. (1986) proposed vacuum packaging is the best way to maintain the quality and hardness of persimmon fruit preservation method. This shows that the development and popularization of storage and preservation technology is increasingly valued by producers, operators and consumers.
The other part of the equipment required for vacuum packaging is packaging containers, packaging containers of more types, plastic, plastic and paper, aluminum foil and other composite materials such as composite materials, glass bottles, metal containers and hard plastics, etc., the selection of packaging containers should be based on the nature of the vacuum-packed food to determine, such as canned food should be applied to glass bottles or metal cans, such as traditional Chinese medicine with aluminum foil or plastic, etc.. Although there are more kinds of container materials for vacuum packaging, the most common is plastic film. If you ask us which variety of bag should you choose when selecting a packaging bag? Well, we would proudly recommend to you: . And what kind of reasons are there? Below, we will introduce you to the two main reasons.
First, there is a very good "air barrier". We know that items, especially food, especially afraid of oxygen, because oxygen is an important basis for the survival of many organisms, but bacteria are also living things, some bacteria can be in the presence of oxygen to reproduce in large numbers, never jeopardize the quality of food and other items. However, the vacuum bag, as the name suggests, the bag must be in a vacuum or near-vacuum state, therefore, can play a very good "gas barrier", in fact, the vacuum bag can not only play a role in isolating the role of oxygen, but also isolate carbon dioxide and other gases.
Second, the use of vacuum packaging bags safety. Vacuum packaging bags using "green" production concept, the production process does not add adhesives and other chemicals, are green products. Vacuum packaging bags, is the product into the bag after the bag of air out of the bag after sealing a product packaging method. Certain long-distance transportation of fatty foods, such as marinated products, ham, grilled fish, Beijing duck, Texas steak chicken, etc. in the air and oxygen contact for a long time will be easy to deteriorate after the fat-rich food must be the choice of vacuum packaging bags, preferably high-temperature cooking vacuum packaging bags. After high-temperature sterilization of the bag not only in the food to provide a safer preservation environment, but also in the aluminum foil pouches itself on the safety of a better guarantee. In addition to the technology of high-temperature cooking and sterilization, it also provides reflective aluminum foil material that can perfectly avoid sunlight for foods that cannot be exposed to sunlight. In order to prevent the bag from being punctured, PA is also deliberately added. with the vacuum packaging bag, the fresh taste and color of fat products can be preserved until opening.