Writer：Peter | Time：2020-07-29 16:07 | Browse：℃
Our tin box company, Dongguan Xihong Industrial Co., Ltd., are located in Shilong Town, Dongguan, Guangdong Province, which are professional on making tin box for around 18years.
Tin box which are consist of tinplate, its abbreviation is SPTE, which is primarily steel with a very thin tin coating. Tin material are mainly plays a role in preventing corrosion and destruction. Tin plate not only has the strength and formability of steel, but also has the corrosion resistance, solderability and good appearance of tin. Its combination makes tinplate to be a material which are anticorrosive, non-toxic and with high strength.
Tinplate has been called “Marco Iron” for a long time in China. Because there has a group of people thought that the tinplate which produced for making can are bought from Marco, therefore they called it “Marco Iron”. But the name “Marco Iron” cannot exactly match what the material really is. Hence, this material are been officially called tinplate since 1973 China’s tinplate meeting. And also in official document, it cannot use the name “Marco Iron” anymore.
Due to its good sealing, preservation, light resistance and sturdiness, tinplate is widely coverage in the packing container, and has become one of the international general packaging. Tinplate is full of innovation as the continuous enrichment of CC materials, DR materials, and the chrome-plated iron, which also promote the development of packaging product and technology.
Tinplate are in hot sell those years because its strong anti-oxidation, diverse styles and exquisite printing. It is widely used in food packaging, pharmaceutical packaging, daily necessities packaging, instrumentation packaging and so on.
Tinplate packaging has already established a fabulous reputation in the international market, therefore, many countries have pay great attention to this tinplate packaging, tinplate has also become the largest amount of metal packaging sheet in the world.
According to the different requirements of the packaging, there will have different needs for the thickness of tinplate, the amount of the tin plating and also the mechanical properties. Since its appearance, tinplate has been developing in the direction of being thinning. There are two methods: one is to use as less tin as possible, and even no tin, and the other is to reduce the thickness of the tinplate substrate. All of these methods are aim to reduce the cost for can-making.
The application of tinplate packaging is becoming more and more extensive with the improvement of the printing technology and processing technology. The needs for tinplate imports will gradually decrease with the continuous increase production capacity national. Our tinplate are basically achieved self-sufficiency except for some high-end products. In 2010, the domestic metal packaging container sales revenue exceeded 50 billion Yuan, which also brought the metal packaging into a new high period.
Tinplate originated in Bohemia( now in Czech and Slovakia). This place has been rich in metal since ancient times, and people are capable of using water power for machine manufacturing. Tinplate has been produced since the 14th century. The army from various countries made a great large number of iron containers( canned food) for the First World War, and that’s how it continue to use it to today.
In addition to causing food degradation reactions, light also will lead to changes in proteins and amino acids. Vitamin C is more easy to interact with other food ingredients when it exposed to light. According to research and analysis, the loss of Vitamin C in milk in transparent glass bottles is 14 times higher than that in dark bottles. Light can also cause the oxidation of milk, and let it has odor, as well as the split of nuclides and methionine, and then it will lose a lot of nutritional value. The opacity of tinplate keep the Vitamin C in the highest preservation rate.
The barrier of packaging container to air and other volatile gases is very important for the preservation of nutrients. In the comparison of various juice packaging containers, it proves that the oxygen permeability of container directly affects the browning of the juice and the preservation of Vitamin C. The metal can with low oxygen permeability, glass bottles and the aluminum foil laminates, and paper box, those packaging containers can preserve the Vitamin C in well condition, among which, the tin can is the best.
The tin on the inner wall of the tinplate box will interact with the oxygen which remaining in the container. Because the reduction of tin, it can reduce the chance of food ingredients being oxidized. The reduction of tin, also has a good preservation on the flavor and color of the light-colored fruits and juices. Therefore, the use of unpainted iron cans in juice cans is better in nutrient preservation than those in other packaging materials, and the brown changes are also slight.
Tinplate is widely used in many aspects, which from the packaging materials for food and beverages to oil can, chemical tin can and other miscellaneous store tin box. The advantages and characteristics of tinplate provide good protection for the contents inside not only in physical but also in chemical.
Tinplate can ensure the sanitation of food, and can minimize the possibility of corruption. At the same time, it also meets the need for convenience and speed of modern people’s diet. Tin plate is the first choice for tea packaging, coffee packaging, candy packaging, cigarette packaging, gift packaging...
Tinplate cans can be used to fill juice, coffee, tea and sports drinks, as well as cola, soda, beer and other beverages. The tin cans can be placed in a variety of configurations with high workability. Whether in tall, short, large, small, square or round, it can all meets the needs of consumer various preferences.
Light will accelerate the oxidation reaction of oils and fats, reduce the nutritional value, and produce harmful substances. And it will also destruct the oily vitamins, especially Vitamin D and Vitamin A.
Oxygen in the air promotes the oxidation of oils and fats in food, reduces the biomass of proteins and destroys vitamins. The opacity and the good tightness of tinplate makes it to be the best choice to store the oil food.
Tinplate cans can withstand high temperatures and pressures are particularly suitable for high-pressure filling spray cans.
Biscuit buckets, stationery boxes and milk powder tins, are all in tinplate, which can be various shape.
With the printing pressure, tinplate printing utilizes the physical properties of repellence between water and ink, transferring the printing plate image into the tinplate through blanket, which is similar to lithographic offset printing. But due to tinplate’s special physical and chemical characteristic and the reprocessing performance, its printing process is quite different from the ordinary offset printing.
Since tinplate prints are ultimately made into food cans, toys, spray cans and also cans for chemical products, they need to be cut, bent and stretched. Therefore, printing inks are required to have good adhesion and corresponding machinery performance.
In order to improve the ink adhesion, the tinplate needs to be primed in white color before printing. As we all know, white is the basic color for all pictures, and has a high brightness. After adding other high-energy hues, the brightness of each hue can be improved to form a gradation.
The surface of tinplate is silver-white(or yellow) with metallic luster. Before printing colorful image, the surface needs to be painted white or printed white . Due to the limitation of ink coverage, the monochrome machine often needs to print white color twice, after that its whiteness can up to 75%. Whiteness as an important factor to measure the print quality of tin plate, it requires the white ink has great binding force with the primer. It should be not yellow after repeated high -temperature baking and steaming.
Priming tinplate can increase the adhesion between colorful image with tinplate, and also the whiteness with tinplate. The most common primer we used is the epoxy amine type, which has light color, and after repeated baking and steaming, it will no yellow, aging, and has good flexibility.
In additional to having water resistance, the color ink for tinplate printing should also have other special requirements. The tinplate needs to be baked and dried when printing since the surface of tinplate is impermeable to moisture and solvents, therefore the ink also should be in thermal curing type. It has high requirements for the tinting power and durability.
Therefore, in additional to have the basic characteristic of the general offset printing, the ink for tinplate printing should also have the performance of heat resistance, strong adhesion, good rigidity, baking and steaming resistance and also light resistance.
During the production of tinplate printing, the ink drying is a complicated physical and chemical reaction process. In order to carry out rapid printing operations and ensure printing quality, it is necessary to control the drying speed in a reasonable rate, and to grasp the physical and chemical mechanism.
If the speed of drying ink too quickly, it will reduce the transfer performance of ink and affect the production. It will makes the printing color in pale, and the blank part becomes dirty. However, if the ink dries too slowly, it will difficult to overprint, and it will lower the adhesion, combination, and firmness.
Therefore, the drying speed of the ink should control in a reasonable rate, it cannot be too slowly or too quickly.
The printing production line is generally composed of tinplate input device, offset printing device, coating device, drying room. Tinplate printing process usually needs to be completed on the production line according to the following procedures:
According to the characteristics of the inner contents, tinplate usually need to be coated with a certain coating on the inner surface of the container, to prevent the contents from eroding the can or the contents from being contaminated. And such coating will also benefit for long-term storage.
Such as for candy box, in order to prevent post-processing curling, rusty, it is also necessary to apply a layer of decorative coating to beautify the appearance.
The inner coating are various, but tinplate are generally coated with phenolic resin coating, epoxy-phenolic resin coating, acrylic resin coating and aluminum powder coating, etc. The inner coating type and the coating thickness will be adjusted according to the different characteristic of the inner content.
In generally, the tinplate can will be printed first before making it into can. In the can-making process, tinplate need to be bent, stretched, welded, overturned, rolled. Therefore, the dry coating and the ink layer not only need to have the sufficient strength, but also to have enough adhesion, otherwise it will lead to deformation or cracking of coating and ink layer, or even falling off the tinplate during the forming process. Hence, to improve the adhesion, it is necessary to apply a layer of paint or primer between ink and tinplate. It also have been mentioned in the special requirement for ink above.
The plate making of the tinplate printing is slightly different from other plate-making methods, there also have special requirements for the tinplate printing:
Tinplate needs to be processed and formed after printing, therefore the welded edge should be reserved for it to ensure the text or image does not deviate from the center after processing and forming.
To ensure the need for subsequent welding, all welded products such as spray can must not have graphics and color point on the seam.
Tinplate can be printed on the machine after the above procedures. Tinplate printing generally uses offset printing, because the surface of the tinplate is smooth, and it cannot absorb ink. Printing ink have special requirements as the description above.
A layer of gloss oil need to be put above the tinplate after it finishing all the printing. Which will increase the gloss and improve the scratch resistance of the surface.
The gloss oil people normally use are epoxy resin, alkyd resin, acrylic resin, acrylic amino, etc. They have different ingredients, performance and uses.
In order to improve the production efficiency and save energy, the last printing process is generally combined with the oil-brushing process.
Gloss oil not only has shiny gloss oil, but also mat gloss oil, cracker gloss oil, and pearl gloss oil and so on. The shiny gloss oil makes the tinplate surface has a sense of luster, which is in line with people’s traditional aesthetics. The mat gloss oil, in the opposite way, makes the surface of the tinplate matte without a sense of luster, but with elegant decorative effect.
Rest and wait for the surface ink to dry.
The packaging containers which include tinplate cans, aluminum cans, paper and plastic containers, are all have different recycling characteristics. Tinplate are better than other packaging materials in recycling.
Based on the implementation of the international environmental management standard ISO-14000, the tinplate, which is in low pollution, recyclability and resource-saving, will have broader development in the future packaging applications.
Tinplate, the main raw material for the tin cans, actually is environmentally harmless and can be decomposed naturally. Tinplate can be naturally oxidized to the original iron oxide in the natural environment. Therefore, tinplate can be decomposed by time. At the same time,it doesn’t need to cut down tress to make tin can, so as not to destroy the ecological balance.
The tinplate can be adsorbed by the magnet, that’s a special characteristic that other packaging materials do not have. Therefore, the tin can can be separated from the garbage by a magnetic machine. This method can recycled around 80% tinplate in the recycling waste.
In order to provide good quality iron scraps, shredder equipment has been developed which can effectively remove more than 98% pollutants in tinplate surface. In addition, in terms of energy saving, the report pointed out that in comparison to the steel iron production, for tin plate production, each ton of iron scrap can save about 230 cubic meter of natural gas. Therefore, the recycling process of tinplate can reduce the influence of the global environment.
Any questions or advise, please feel free to contact us！Make your product to be more popular, view more tin box in Xihong packaging!
Email: [email protected]
Add: Shenshan industrial park, Hengli Town, Dongguan City, Guangdong, China