Book book material and type of use (two)

2. Color foil

Color foil, also called powder foil, is a kind of hot stamping material made by coating pigments, resin adhesives and other solvents on the film base. Hot foil stamping can be used to create a variety of color graphics.

The development and production of colored foils is later than that of electro-aluminum foils, and is mainly used instead of traditional color chips. Its characteristics are: a variety of colors, a wide range of options, can be used for automatic continuous hot stamping process, less waste, easy transport and storage. The foil package is the same as the electro-aluminum foil and is a very popular pigment foil. However, because the color layer of the color foil is thinner, compared with the color film, the color of the color film is not as bright, thick and full.

1 color foil composition. The composition of the color foil is similar to that of the electro-aluminum foil, except that the electro-aluminum foil is vacuum-deposited with a layer of metallic aluminum, and the color foil is directly coated on the base film and is not plated with aluminum. The color foil consists of three or four layers.

Three-layer color foil production method:

The first layer is a base film layer. The base film is generally a 12 to 16 μm thick polyester film. It mainly acts as a supporting coating. Its packaging form is a reel type, which facilitates continuous processing, storage and transportation.

The second layer is a release layer. The coating of the release layer is a silicone resin or a wax liquid, and its function is to make the color-adhesive layer quickly detach from the base film and adhere to the material to be heated during hot stamping. Detachment layer must have a good shedding effect, otherwise it will cause hot stamping color, uneven, and other quality problems.

The third layer is a color layer. The color-adhesive layer is mainly composed of a pigment, and then a binder, an alcohol solvent, and other fillers are added and mixed in a certain proportion. The various colors of the colored foil are mainly dependent on the coating and formulation of this layer. Commonly used red, yellow, green, black, etc., are made according to user requirements and coated. Due to the addition of adhesive, it can be hot pressed by hot stamping to firmly bond it to the object to be heated.

The four-layer color foil separates the color-adhesive layer, and its purpose is to overcome the defect of the insufficient adhesion material in the color-adhesive layer to ensure the hot stamp adhesion.

2 color foil performance and hot stamping. Due to the differences in the production process, batch, etc., the color foil must be well-understood in performance and use. The color foil is classified by a base film, including a polyester film and a paper film; it is classified into a color-adhesive layer binder and is divided into a water-soluble foil and an alcohol-soluble foil. Some foils are suitable for hot stamping large area patterns, while others are suitable for small area graphics and foils with patterned patterns, so they must be selected according to need.

A. The performance of colored foils. The properties of the colored foil are determined by the nature of the polymer selected. In the hot stamping process, it must have good detachment, adhesion, and can accurately display a variety of colors. When making colored foils, it must be accurately understood that the thickness of the coating is uniform, typically 0.05 mm. In addition, the color material in the color-adhesive layer must be mixed with the binder to be coated.

B. Hot foil stamping. The color foil foil stamping is more difficult than the electro-aluminum foil, especially if there is a large color difference with the surface of the workpiece to be ironed. If the material is improperly selected or is not well-handed, there will be quality problems such as missing bottom, pattern, discoloration, and stencil. Therefore, according to the texture, form, pattern depth, and thickness of the mesh, the pressure, time, and temperature are properly grasped during hot stamping, so that the image after hot stamping can be clear, plump, and bright. Firmly does not fall off.

3. Color film

The color film is a kind of hot stamping material that is coated on paper and other flat and smooth objects by depositing a layer of mixed paint such as a pigment and a binding material, and drying and peeling off the paper.

The color film has a history of nearly 60 years; before the color foil was used, all kinds of colored imprints were stamped with this material. The feature of the color film is that it is simple to make, bright in color, full and thick in the trace, pure in color, and not easy to reflect after encountering light. However, since the color plate has no support body, it is easily broken and it is difficult to continuously print. Because the effect of hot stamping and printing with color chips is good, multi-color high-grade books use hot-chips for hot stamping. The use of color film can be arbitrarily made and selected according to the needs of the hot stamping must master its performance. Because the color chips are not supported, they must be cut into the necessary width in advance during processing, and hot stamping should be performed after the hot stamping position.

4. Metal foil

Metal foil is a thin metal sheet that is expanded with metal. The use of metal foil to stamp certain items has been around for more than a century in China. In the 15th century, books were decorated with red gold foil.

There are several kinds of metal foils, including red gold, silver foil, copper foil and aluminum foil. Among them, many are used in red gold foil and used for the longest time. To date, some valuable books with preservation value are still stamped with red gold foil because of the red gold foil. Not easy to oxidize can permanently shine.

1 red gold foil hot stamping. The red gold foil is made of pure gold. The appearance of the red gold is very gorgeous. The texture is soft, the chemical properties are stable, it is not easy to lose its luster due to oxidation, and the ductility is the best one of the metals. The thickness of the red gold foil used for hot stamping is only about 2 μm. A flat sheet of gold foil is used for packaging.

The use of red gold foil for hot stamping is difficult and requires a certain amount of operating skills and experience. The operation process is: cutting gold - cutting the gold foil to the desired format specification; exposing the gold - using the camera to lift the gold foil with the paper; gold - the gold foil to be lifted on the hot stamping; ——The hot stamping of the gold to be laid is placed in the hot stamping machine for hot pressing; cleaning – the excess red gold foil will be cleaned in the storage box immediately after the hot stamping. The key to hot red gold foil is to expose gold and gold. If you have a good grasp, you can save gold foil and process it smoothly, otherwise it will cause great waste.

2 pure silver foil and hot stamping. Pure silver foil is made from pure silver. Silver is soft and ductile, second only to red gold, so pure silver foil is slightly thicker than bare gold foil. Silver is gorgeous, chemically stable and easy to store. It is also a more expensive hot stamping material. Prior to the absence of electro-aluminum foil, the silver prints were almost always foil-stamped.

The processing, packaging and hot stamping of silver foil are basically the same as that of red gold foil, but the silver foil is thicker and is more convenient than red gold foil in hot stamping. The history of the use of silver foil is also very long, but the amount of use is very small, because generally there are gold-based books that have a preservation value.

In addition to the red gold and silver foils, there are copper and aluminum foils instead of gold and silver. During the processing, the transparent paper base impregnated with resin or wax is coated with a layer of resin adhesive, and the previously ground copper or aluminum powder is coated thereon and then pressed evenly with a roller and dried. production. Copper and aluminum foils are not suitable for extension and are easily oxidized, so they are rarely used. Its packaging is the same as the color film. After electro-aluminum foil, copper foil is no longer used.



Source: YORK