Five processes that are not known to bronzing paper
The process of uncovering hot stamping
paper! Bronzing paper is essentially a carrier coating transfer coating film. According to the international production standards, there are five general process flows. According to the difference in the materials or complexity of the five processes, it is also one of the important reasons for determining the price difference of the hot stamping
paper market today. The specific production process is as follows:
Carrier: It consists of polyester film or polyester film to support other layers. Conventional production PET polyester film is often used as a carrier for hot stamping
paper (aluminized aluminum). The PET film is selected as the carrier layer because the PET film has the following characteristics: high temperature resistance (melting point at 170 ° C), easy degradation (flammable film, strong electrolytic ability, not easy to cause environmental pollution), uniaxially stretched film (longitudinal pull) Stretch has good ductility and is not easy to break, and transverse stretch is easy to break). Other common features such as OPP film and PVC film do not have these advantages. For example, the heat-resistant temperature of the OPP film is 90 ° C, which is a combustion-supporting film; the heat resistance temperature of the PVC film is 75 ° C, which is a flame-retardant film. Of course, the melting temperature of the hot-melt adhesive of the outer layer of bronzing paper (aluminized aluminum) is about 90 ° C, which is one of the important factors that determine the choice of PET polyester film as a Hot stamping paper
Coating of the first (1) coating: The first coating is called a centrifugal layer, which is also called a peeling layer. When hot stamping, the color, aluminum and rubber layers can be quickly separated from the PET film and transferred to the surface of the object to be stamped. The materials commonly used in the peeling layer are mainly silicone oil, paraffin wax and water wax. These three materials have the same effect in the stripping process, but their respective physical properties determine their range of use. Silicone oil is a hot-melt coating with a melting point of about 98.7 °C. The spraying process is simple. The disadvantage is that the spraying is uneven and unstable. It is a secondary heating when using bronzing. Generally, silicone oil is not used as a centrifugal layer for hot stamping paper. Paraffin wax has relatively stable physical properties. It requires professional spraying equipment to spray paraffin wax on PET film in the form of solid, powder and mist. It is the peeling coating for hot stamping paper. It is the best peeling of the most commonly used hot stamping paper in the world. Coating material; water wax is generally not used as a release coating material for hot stamping paper because of its relatively low melting point.
(2) coating: The second coating is called a protective layer, mainly using clear oil, ethyl ester, resin, etc. as a protective coating material; this layer is mainly used to protect the pigment layer and the fine aluminum layer. And can enhance the brightness of bronzing paper after bronzing. In order to save costs, some domestic enterprises that produce bronzing paper often save this layer or take this layer and the third layer of pigment layer together, so this is also a lot of domestic hot stamping paper is not as bright as imported bronzing paper. One of the reasons.
Coating (3): The third coating is called the image layer, also known as the pigment layer. It is mainly composed of synthetic resin and dye, and forms the color of bronzing paper. For example, red, blue, green, gold, etc. determine the color or color of the bronzing paper, and it is also the determining factor layer of various types of bronzing paper.
Coating of the (4) coat: The fourth coat is called a finely plated aluminum layer. It is formed by metal aluminum by vacuum high temperature evaporation, cooling, and sublimation deposition. The main function of the aluminized layer is to reflect light and give the dyed layer a metallic luster. There are two common aluminum plating processes, the first is an aluminum-plated vacuum evaporation week, and the second is an aluminum-plated gun. Their respective characteristics are that the evaporation week equipment is relatively expensive, the production process is complicated, and the sublimation of aluminum vapor is mainly used to make the aluminum plating layer uniformly and densely condensed on the PET coating film, and the aluminum plating effect is good; the aluminum plating gun equipment is simple, and the production is simple. The process is also relatively simple, the main disadvantage is that the spraying is uneven, and it is easy to produce black spots on the plating.
Coating (5): The fifth coating is called an adhesive layer. It is mainly composed of hot-melt plastic or resin. Its function is to bond the aluminized layer and the dyed layer to the object to be burnt under the action of pressure and temperature. This layer is an important coating that determines the scope and breadth of the gilding paper. Normally, the manufacturer can combine two kinds of objects that are difficult to bond with each other by adding a secret "active sulphur" to the hot melt adhesive. This is also one of the important reasons for the single application range of many domestic electrochemical aluminum.