The technical features of three-dimensional hot stamping and ordinary hot stamping

The three-dimensional bronzing technology is quite different from ordinary bronzing. In addition to the three-dimensional pattern that can form an embossed pattern, there are differences in plate making, temperature control, and pressure control.

First, plate making

1, ordinary hot stamping version

The high-quality hot stamping version guarantees the quality of the hot stamping. The ordinary hot stamping version is relatively simple to produce, mainly adopting a photo etching process and an electronic engraving plate making process. Commonly used plates are copper plates or zinc plates. Due to its fine texture, smooth surface, good heat transfer performance, wear resistance, and pressure resistance, the copper plate is currently the mainstream hot stamping plate. The use of high-quality copper plates enhances the gloss and clarity of hot stamping graphics. For some hot stamping products with less hot stamping quantity and low quality requirements, zinc plate can also be used.

Photo etching plate making is a traditional manufacturing method with simple process, low cost, and low precision, and is mainly applicable to images whose characters, bold lines, and quality are not high. The hot stamping plate made by electronic engraving can enrich the delicate image representation level, and can reproduce the fine lines and graphics with uneven thickness, but the relative cost is high.

2, three-dimensional hot stamping version

The production principle of the three-dimensional hot stamping printing plate is the same as that of the ordinary hot stamping plate, but it is more complicated than the normal printing plate because it needs to form a three-dimensional relief pattern. The hot stamping plate is generally concave, and has a depth and depth change, and the depth is also higher than the ordinary hot stamping. Plates are deeper and more accurate. At present, the copper plate photographic etching method is mainly used in China. This method has the advantages of low cost and simple process, but it is only suitable for flat hot stamping. Due to poor three-dimensional sense, short service life, and resistance to printing force, it is only about 100,000 impressions, so it is commonly used in some packages that do not require high relief effect. On the product.

At present, the brass plate has been widely used in foreign countries. Scanners are used to first scan the pattern to be stamped, store the data in a computer, and then carry out three-dimensional engraving through computer and software control to form a gravure intaglio with a rich three-dimensional pattern. Because it is controlled by a computer, it can form a very fine pattern, and it is more ideal for subtle parts. It can withstand up to 1 million impressions or more, so it is very suitable for making three-dimensional hot stamping with high quality and large quantity. Die intaglio. Of course, due to the need to provide high-end electronic engraving machines, scanners, computers and software, engineering and technical personnel, etc., the production cost is higher than the photographic corrosion method. Because of its complicated production and technical difficulty, it can prevent some counterfeit companies from counterfeiting and have certain anti-counterfeiting functions. Therefore, for some long-lived products with high quality and requiring anti-counterfeiting features, such as cigarette packs, wine bags, health products packaging and greeting cards, etc., it is appropriate to use three-dimensional hot stamping. In the past, such hot stamping plates had to be processed abroad. The cost was high and the delivery was not timely. The design effect was also unsatisfactory. At present, a small number of manufacturers in China have been able to process this hot stamping version, which has effectively reduced the cost. In particular, direct communication between the processing manufacturer and the design personnel can correctly understand the design intent and achieve satisfactory results.

Second, the bottom mold letterpress

Stereoscopic bronzing is different from ordinary gilding. The ordinary gilding plate is flat and does not require special production. The bottom plate of the three-dimensional bronzing must be a positive mold platelet corresponding to the hot plate, that is, the concave area of ​​the hot plate should be on the bottom plate. It is convex, and the height of the bulge corresponds to the depth of the hot plate depression. The method for making the bottom mold relief is the same as the method for making the male mold relief of the embossed stamp. The commonly used materials include plaster and glass fiber. If gypsum is used, it must be completed on the machine. Therefore, the process is more complicated and the replacement of the bottom plate is troublesome, but the cost is low, and it is now commonly used in China. If glass fiber is used, it can be prefabricated according to the model of the hot stamping plate, and the positioning holes can be made with the processed copper plate to facilitate the replacement of the positioning.

The bottom mold relief is to form a three-dimensional relief pattern in order to cooperate with the stamping gravure, which must exactly correspond to the hot stamping version. However, the three-dimensional hot stamping is different from the embossing and embossing. Most of the embossing and embossing do not require heating, and the three-dimensional hot stamping must be heated at high temperature During hot stamping, as the temperature rises, the hot stamping plate expands, but the temperature of the bottom mold stamping remains basically unchanged. This results in a mismatch between the hot stamping plate and the bottom mold relief plate, resulting in a crushing bottom mold. Or can not hot stamping phenomenon. Therefore, when making the bottom mold relief, the expansion rate of the hot stamping plate should be fully taken into account to make an accurate bottom mold relief plate.