Analysis of the advantages and disadvantages of hot stamping technology
We are a big printing company in Shenzhen China . We offer all book publications, hardcover book printing, papercover book printing, hardcover notebook, sprial book printing, saddle stiching book printing, booklet printing,packaging box, calendars, all kinds of PVC, product brochures, notes, Children's book, stickers, all kinds of special paper color printing products, game cardand so on.
For more information please visit
http://www.joyful-printing.com. ENG only
http://www.joyful-printing.net
http://www.joyful-printing.org
email: info@joyful-printing.net
At present, hot stamping has become an important metal surface finishing method, which is an effective way to enhance the visual effects of labels, cartons, trademarks, etc., and is widely used. The hot stamping method mainly includes hot stamping and cold stamping, both of which have their own advantages and disadvantages. Therefore, in practical applications, the appropriate hot stamping method should be selected according to the specific situation, especially in weighing the cost and quality. More attention should be paid.
Hot stamping technology
Hot stamping technology refers to the transfer of hot stamping foil to the surface of the printing material by means of a special metal hot stamping plate by heating and pressing.
1. Advantages and disadvantages of hot stamping technology
The advantages of hot stamping technology mainly include the following points.
(1) The quality is good, the precision is high, and the edge of the hot stamping image is clear and sharp.
(2) The surface gloss is high, and the hot stamping pattern is bright and smooth.
(3) Hot stamping foil has a wide selection range, such as hot stamping foil of different colors, hot stamping foil with different gloss effects, and hot stamping foil suitable for different substrates.
(4) The hot stamping process also has a prominent advantage, that is, it can perform three-dimensional hot stamping. The three-dimensional hot stamping plate is made by computer numerical control engraving and engraving (CNC), which makes the image printed by hot stamping have obvious three-dimensional layer, and forms a relief effect on the surface of the printed matter, and produces a strong visual impact effect. Three-dimensional hot stamping gives the package a unique touch.
It is precisely because of the many advantages mentioned above that the hot stamping process has been favored by users and consumers, and the application is very extensive. However, the hot stamping process requires special equipment, requires a heating device, and needs to make a hot stamping plate. Therefore, obtaining a high-quality hot stamping effect also means a higher cost.
Mr. Chris Corbett, International Sales Manager of ITWFoilmark, pointed out that the high price of rotary hot stamping cylinders is a large part of the hot stamping process cost, which is the main cost factor of the hot stamping process. At the same time, he also pointed out that in the past five or six years, the price of hot stamping cylinders has been greatly reduced, and the drop rate is as high as 50%. In addition to reducing the cost of hot stamping cylinders, hot stamping system suppliers have also challenged the hot stamping speed limit. In the past, due to the limitation of hot stamping speed, most of the hot stamping work was done offline, and the situation is very different now. A few years ago, the hot stamping speed of hot stamping machines was less than 5,000 sheets per hour. At present, whether it is a platform type hot stamping machine or a drum type hot stamping machine, the speed can reach 7500 to 12000 sheets per hour. Of course, the speed of hot stamping has a certain relationship with the type of machine used. The continuous increase in production speed has greatly reduced the cost of hot stamping.
2. Development trend of hot stamping technology
One of the future development trends of hot stamping technology is online hot stamping.
The improvement of the chemical properties of the hot stamping foil provides a reliable guarantee for the rapid increase of the hot stamping speed. Therefore, the hot stamping process has been completed online, and the application of the inline hot stamping process will become more and more popular in the future. In addition, sheetfed folding carton printing is moving in the direction of web printing, which also creates conditions for the inline hot stamping process.
Another development trend of the hot stamping process is to apply hot stamping, that is, hot stamping and then overprinting on the hot stamping foil. The hot stamping process also benefits from the improvement and improvement of the chemical properties of the hot stamping foil, so that UV ink can be used for printing on hot stamping foil. The hot stamping process provides a more decorative effect and enhances the visual appeal of the image.
Overprinting and then printing opaque or transparent color inks can achieve fascinating effects, providing packaging designers with endless design solutions and providing designers with ample space to fully express their creative talents.
[NextPage]
Cold stamping technology
Cold stamping technology refers to the method of transferring hot stamping foil to a printing material by using UV adhesive. The cold stamping process can be divided into dry film type cold stamping and wet film type cold stamping.
The dry film type cold stamping process is to cure the coated UV adhesive before hot stamping. Ten years ago, when the cold stamping technology was just released, the dry film-type cold stamping process was adopted. The main process steps are as follows.
(1) Printing a cationic UV adhesive on a roll substrate.
(2) Curing the UV adhesive.
(3) The cold stamping foil is combined with the printing material by means of a pressure roller.
(4) Peel off the excess hot stamping foil from the printing material and leave only the required hot stamping on the adhesive coated area.
It is worth noting that when using the dry film-type cold stamping process, the curing of the UV adhesive should be carried out quickly, but it cannot be completely cured. It must be ensured that it has a certain viscosity after curing, so that it can be very hot with hot stamping foil. Goodly bonded together.
The wet film type cold stamping process is to apply hot stamping and then to the UV adhesive after the UV adhesive is applied. The main process steps are as follows.
(1) Printing a radical type UV adhesive on a roll substrate.
(2) Composite cold stamping foil on the substrate.
(3) Curing the radical type UV adhesive. Since the adhesive is sandwiched between the cold stamping foil and the printing material, the UV light must pass through the hot stamping foil to reach the adhesive layer.
(4) The hot stamping foil is peeled off from the printing material, and a hot stamping graphic is formed on the printing material.
It should be noted that: First, the wet film type cold stamping process replaces the traditional cationic UV adhesive with a free radical UV adhesive; second, the UV adhesive has a strong initial adhesion and cannot be cured after curing. It is viscous; thirdly, the aluminized layer of the hot stamping foil should have a certain translucency to ensure that the UV light can pass through and cause the curing reaction of the UV adhesive.
The wet film-type cold stamping process enables hot stamping of metal foil or holographic foil on the press, and its application range is wider and wider. Currently, many narrow carton and label flexo presses have this type of cold stamping capability.
1. Advantages and disadvantages of cold stamping technology
The outstanding advantages of cold stamping technology mainly include the following aspects.
(1) There is no need for special hot stamping equipment, and the price of these equipment is usually relatively expensive.
(2) It is not necessary to make a metal hot stamping plate, and an ordinary flexographic plate can be used, which not only has a fast plate making speed, but also has a short cycle, and can also reduce the manufacturing cost of the hot stamping plate.
(3) Hot stamping speed is up to 450fpm.
(4) No heating device is required and energy can be saved.
(5) Using a photosensitive resin plate to complete the hot stamping of the mesh image and the solid color block at the same time, that is, the mesh image and the solid color block to be hot stamped can be made on the same hot stamping plate. Of course, the same as the net color and the color block system printed on the same plate, the hot stamping effect and quality of both may have a certain loss.
(6) The hot stamping substrate has a wide range of application, and can also be stamped on heat sensitive materials, plastic films, and in-mold labels.
[NextPage]
However, cold stamping technology also has certain deficiencies, including the following two points.
(1) The cold-hot stamping usually requires film or glazing for secondary processing protection, which increases the cost of hot stamping and process complexity.
(2) The coated high-viscosity adhesive has poor leveling property and is not smooth, which causes diffuse reflection on the surface of the cold-hot stamping foil, affecting the color and gloss of the hot stamping graphic, thereby reducing the aesthetics of the product.
Mr. J. Michael Rivera, Deputy General Manager of Sales at AMAGICHologrphics, said that although the hot stamping process cannot achieve the high definition and high definition of the hot stamping process, cold stamping technology can bring many advantages to flexographic printers, including: The equipment has less initial investment, lower plate making cost, faster hot stamping, and can be done online on the press. It can be used on materials that are not suitable for hot stamping (such as film without substrate, PET and plastic bags, etc.). Hot stamping, etc.
On the film and non-absorbent paper materials, the cold stamping technology can achieve the best hot stamping effect. On the contrary, when the cold stamping is performed on the porous material with high permeability, the effect is not ideal. However, Mr. Rivera pointed out that some AMAGIC customers have stamped on Raflatac Raflasilk matt PSA materials, and the feedback results are quite good. Other customers can also get a better cold stamping effect by applying primer and glue on matt paper materials.
At present, cold stamping technology has become a strong competitor of hot stamping technology, and cold stamping technology is expanding from narrow flexographic printing to other printing processes, such as wide flexographic printing, embossing, web offset printing and printing. Sheet of paper offset printing, etc. For example, at Drupa2004, the Roland 700 sheetfed offset press equipped with Manroland's new PrindorInLine cold stamping unit was exhibited.
Cold stamping technology provides new opportunities for printing companies. Its biggest advantage is that it has little or no investment. Another outstanding advantage is the high cost performance, which is also the biggest selling point of cold stamping technology. As one industry insider said: “For customers, cold stamping technology is more cost-effective and can help customers increase the added value of their products, and it is very economical.” In addition, because cold stamping technology does not need to make expensive hot stamping plates, Therefore, it is very suitable for short-lived, low-quality labels and proofing production. However, compared with the hot stamping technology, the cold stamping technology still has certain defects in quality, which needs to be further improved. Therefore, the cold stamping technology is not suitable for the processing of high quality packaging and label products.
Here, I would like to mention that although gold and silver ink printing can also play a metallic glossy decorative effect similar to hot stamping, and in recent years, gold and silver ink printing technology has also made great progress, but still can not reach The strong visual impact of hot stamping or cold stamping.
2. Conditions required for cold stamping process
In general, cold stamping can generally be used for jobs printed on UV flexographic presses.
The equipment and materials required for the cold stamping process are as follows.
(1) Standard flexographic printing or embossing unit.
(2) Photosensitive resin plates and anilox rolls, and there must be enough spare anilox rolls to choose from.
(3) The embossing roller with a hardness of HS90 must be easily installed in the printing unit, and it must be ensured that sufficient pressure is provided to ensure the smooth printing.
(4) Hot stamping foil unwinding device and winding device. Pay attention to adjusting the winding tension when cleaning the waste to avoid wrinkles or delamination of the hot stamping material.
(5) Hot stamping foil.
(6) UV adhesive.
(7) UV curing system. The UV curing system must be as close as possible to the imprinting device in order to cure the UV adhesive in time after printing and hot stamping. Moreover, the power of the UV curing system is required to be at least 300W. The UV lamp and the reflector must be kept clean and free of UV varnish and dust impurities, so as not to affect the curing effect of the UV adhesive.
(8) Stripping device. The stripping device is installed at the rear end of the UV curing system. In addition to stripping the waste foil, the device can avoid delamination of the hot stamping foil before UV curing, and can also reduce the wrinkles and skew of the printing material.
In addition, in order to obtain high-quality hot stamping products and high profit margins, skilled operators are also required to be able to handle and solve various problems in the production process, especially those related to UV systems.
Conclusion
In actual production, in the end choose hot stamping technology or cold stamping technology? The answer is: it should be based on the specific circumstances. Hot stamping technology can achieve the best hot stamping quality and hot stamping effect, but the cost is higher. The quality of cold stamping is good, but it is inferior to hot stamping, but the cost is lower. Regardless of which hot stamping technology you use, you should pay attention to these two hot stamping techniques, because the price of hot stamping is constantly being adjusted, and the quality of cold stamping is constantly improving. Progress and development.
When printing companies decide whether to invest in cold stamping technology, they must understand the situation of the company's printing press in combination with the actual situation of the company, because the cold stamping process means that a printing unit is replaced by a cold stamping unit, and it needs to be installed. Stripping device, if the number of color groups of the printing press is not enough, it may affect the normal printing of the job.
In addition, it is necessary to judge whether the job is suitable for the cold stamping process. Careful study of the text and text to determine whether it will achieve the desired results after cold stamping. Printing companies can work with UV adhesive suppliers to test cold stamping, provide customers with more choices and improve their ability to serve customers. On the basis of existing customers, it can also enhance the competitiveness of the company itself and the potential to create consumer demand for the customer's products.