Bronzing and embossing after hot stamping

2022-08-22
  • Detail

Post press processing - bronzing and embossing

release date: Source: China's paper industry

heat pad printing technology is commonly known as bronzing. In the early days, the bronzing industry was not much on printed matter. The reason can be summarized into two points: first, the bronzing machine still remained on small machines in the 1960s and 1970s, such as manual bronzing machine, 13 inch × 18 inch Heidelberg air hose machine and small flat pressing and bronzing machine. At that time, if there was a large area or on-site bronzing, it could not be pressed. The packaging plate of large paper row should be set accurately, and the large paper should be cut carefully before bronzing, resulting in slow bronzing lifting speed and inaccurate setting, which made the printer a big headache. At that time, it was mostly hot stamping hardcover leather cases, book envelopes, covers, envelopes, stationery, greeting cards, etc., while color box bronzing was not popular. Second, it was precisely because bronzing was not popular and no one promoted it. Until the early 1980s, a Hong Kong company introduced Japan's larger bronzing machines, such as pool deposit machines

after promotion, printing merchants can see that they can hot stamping full sheets, the set position is accurate, and the shipment is fast, so they are able to receive orders with large hot stamping area; The introduction of fully automatic Heidelberg bronzing machine has made the bronzing industry more vigorous. Until now, the demand for printing and packaging bronzing is increasing day by day. There are many kinds of bronzing machines. Bronzing actually seems simple, but it has its own knowledge. The bronzing industry can be simply divided into paper bronzing and plastic bronzing. The machinery of the two industries is also different. Paper bronzing machines can be roughly divided into:

first, manual small bronzing machines, which can only hot stamp papers with smaller sizes

II. Flat pressing and bronzing machine. This machine has a variety of sizes, ranging from small to large folio paper. It is equipped with a computer program to pull gold foil. The speed is slow, and the process is mostly manual

III. manual beer box bronzing machine, which is similar to manual beer box bronzing machine, and the size can be hot stamped to 28 inches × 40 inch paper size, the process is also mostly manual, and the speed is slow, which is rarely used in Hong Kong

IV. Heidelberg full-automatic rolling bronzing machine, Heidelberg letterpress machine can be said to be the top machine in the past. In fact, this bronzing machine was refitted from letterpress machine. Because letterpress printing has been replaced by offset printing, the machine factory has used its brain to refit this machine into a fully automatic bronzing machine, mainly to refit the part of the font into a heating plate and the place where the bronzing plate is embedded, and add the components of gold receiving paper. This machine has a good effect on ironing fine lines and large fields

v. flattening full-automatic bronzing machine, which is similar to the full-automatic beer box machine, is more expensive, and there are not many users, but the speed is the fastest type of machine, and the hot stamping area is also large

VI. automatic air hose bronzing machine, refitted from Heidelberg letterpress air hose machine, with a paper size of 13 inches × 18 inch, fast, is the necessary tool for most early bronzing plants to make money. The gold foil needs to be basically stable at 140000 yuan/ton. In addition to the bronzing machine, it also needs to be matched with the gold foil. The gold foil looks thin, but it is actually composed of five layers of materials

many people misunderstand that a kind of gold foil can burn any kind of paper products. In fact, there are many kinds of gold foil to match with different materials being burned, such as PP film or polished paper products, metallic ink, cloth, PVC glue, thin line stripes or large field and other materials and printing products, we should choose hot gold foil of different materials to match. Therefore, the price of flash hot gold foil ranges from 10 to 1000, which also depends on the origin and the nature of the material. The price of matte hot cloth and scrapable gold foil is about 700 or more, and that of laser gold foil is over 1000. The gold foil manufacturer has made several gold foils of different colors and quality to adapt to different paper products, and the large-scale, well managed bronzing factory also compiles hot stamping gold foil samples and additional numbers for customers to choose. Customers can also specify a brand of gold foil, such as Barbie doll, an international toy dealer, will specify a brand and a number of gold foil

use different plates

the second is the bronzing plate mold, which is commonly known as the electric plate. The electric plate was widely used in Hong Kong and has a long history. In the early stage of printing, there was the so-called type particles, which were originally used for letterpress printing and later used in the bronzing industry, In the later stage, letterpress printing was converted to Electric Edition (by connecting computers to realize full computer control and print standard experimental reports; the shortcomings of traditional material type experimental machine, such as bulky machine, complex operation and single performance, were completely changed, and zinc zinc was used as plate material), and the bronzing industry has also followed and been used to this day. In recent years, magnesium plates (made of magnesium magnesium) have also been used in Hong Kong. Because magnesium plates have various thicknesses, thicker ones can be corroded deeper. They are used for ironing thick paperboard, cloth grain, or embossing/embossing. The effect will be better. Because they are more durable, there is no need to change plates frequently for hot stamping in large quantities. In addition, copper alloy is used as plate material. Because its hardness is stronger than zinc and magnesium, it can retain a better image level, high definition, reduce the sand surface of the mold material, and it is also feasible to imprint millions of stones. The above zinc, magnesium and copper alloys are suitable for single-layer bronzing and embossing. (single level, beveled engraving)。 There is also the brass Version (synthesized by copper, tint and lead), which is about 7mm thick. It has low hardness and high engravability. It is suitable for hand engraving and motor engraving. It is regarded as an engraving version with clear layers. It is a must for multi-level and special bevel engraving (multi-level, sculpturedengraving). It can be used for embossing/embossing, embossing, three-dimensional relief, and one-time bronzing and embossing. Because the manufacturing process is complex, the plate making price is very expensive, The price depends on the complex requirements of graphics, and copper plates need to be carved in foreign countries, which has not been achieved by manufacturers in Hong Kong for the time being. Pay attention to temperature and pressure in bronzing. If you want to have a good bronzing effect, you must choose appropriate gold foil with good thermal stability, and also need to cooperate with the bronzing machine. For example, the flat pressing and rolling type have different effects, and then match the elements of temperature, pressure and dwell time

temperature - in the bronzing operation, the most suitable temperature is the lowest and clear texture. The temperature of the heating plate of the flat press hot stamping machine is about 110 ℃, while that of the rolling hot stamping machine is 140 ℃ -150 ℃. The most suitable temperature must be found out by experiment. If the temperature is too high, the hot stamping paper will deteriorate and the lines will be blurred

pressure - the weight of pressure depends on the softness and hardness of the material and the texture of the surface. Materials with smooth or soft surface can be under light pressure, while those with rough or hard surface can be under heavier pressure. The flat pressing and bronzing machine is the synchronous pressing of the whole sheet. The starting point of the air hose machine is the line pressing and then turns to the flat pressing. The rolling machine is similar to the line pressing of the offset machine

pressure stop time - based on the shortest and good hot stamping effect, if the time is too long, the gold foil and hot stamping paper will be damaged, and the flash foil will also turn into matte foil

in addition, the patterns to be hot stamped are correctly aligned with the printed patterns. When using a rolling bronzing machine or large-area hot stamping, it is necessary to shrink the negative film used for hot stamping to 99.8% to 99.7% before arranging to make an electric plate, so that the electric plate will be expanded by heat on the hot plate. It turns out that the scratch lottery ticket can also be made by bronzing! The price of bronzing depends on what kind of gold foil is used, whether gold foil is wasted, whether it conforms to the sealing degree, typesetting method, quantity, size, etc., so there is no standard calculation method to unify the quotation

when talking with Mr. Huang Weiqiang of Xinghui bronzing silk printing Co., Ltd., he raised three questions, hoping that those with experience can give advice

The first end of the auxiliary oil cylinder is connected with the clamping jaw.

first, when stamping the cloth leather shell, although it has been pressed deeply, the bronzing foil is easy to fall off

second, printed matter that has passed UV cannot be scalded with gold foil

III. try ironing many kinds of gold foil, imprinting it on black printed matter (such as printed paperboard, tissue paper, black dyed or primary color leather paper, and ironing it on black foil, which will consolidate the leading position of high-speed rail company in the field of testing instruments in a very short time (3 or 4 days) or a long time (3 to 4 months), and it will slowly show spots and shadows. With time, more spots will appear. (gold foil agents say it is related to carbon molecules of printing ink, so they can't guarantee that the use of that kind of gold foil will not change with the printed matter.)

statement: This article is reprinted. The purpose of publishing this article is to transmit market information more widely. The content of this article is for reference only. The copyright of this website article belongs to the original author and the original source. The content is the author's personal views, which does not mean that this website agrees with his views and is responsible for its authenticity. This website only provides reference and does not constitute any investment and application suggestions. Some articles on this website are reprinted and are not used for any commercial purposes. We have notified the author and source as much as possible. If there is any missing or inappropriate information, please contact us in time, and we will correct or delete the relevant content immediately according to the requirements of the copyright owner. This website has the final right to interpret this statement

Copyright © 2011 JIN SHI