How To Identify Different Types Of Plastics For Album Printing?
Both the laser foil and the Holographic Foil are made by laser photography. The laser box is dazzling and dynamic. As far as the printing process is concerned, it is divided into three categories: hot stamping, composite printing, and self-adhesive. Holographic foil is divided into plane holography, stereo holography, photo holography, polygonal holography, color holography, and micro-engraved holography. Anti-counterfeiting is the main focus of album printing and packaging. The laser holographic foil can clearly reproduce the spatial three-dimensional effect of the image after the imprinting process of the album printing, and the layers are quite distinct. When the light shines on the aluminum foil from different angles, it can show colorful color effects. How to identify different types of plastics for album printing?
The basic method of identifying different types of plastics and their composition is achieved by some commonly used analysis and detection instruments, such as an infrared photometer, chromatography, X-diffractometer, chromatographic-mass spectrometer, nuclear magnetic resonance instrument, etc. However, the general plastic packaging album printing factory does not have such equipment. In practical work, there are two kinds of identification methods with realistic and simple, fast and convenient methods, namely, the burning method and the tearing identification method.
① Combustion method. Thermosetting plastics become brittle and coke when heated, but do not soften, while thermoplastics become soft and even melt when they reach a certain temperature. This is the basic dividing line for systematically identifying these two types of plastics. Plastics containing carbon, phosphorus, fluorine, and silicon elements are not flammable or self-extinguishing, while plastics containing sulfur and nitro groups are extremely flammable. Plastics such as ethylene, propylene, and isobutylene have similar structures and similar combustion characteristics to alkanes.
Plastics with benzene rings and unsaturated double bonds emit black smoke when they are tenderly burned, and the plastics will decompose when heated to produce a special odor. For example, polymethacrylate, polystyrene, and polyoxymethylene can be decomposed into monomers by heating; polyethylene and polypropylene are decomposed into hydrocarbons with different carbon numbers; polyvinylidene and polyvinylidene vinylidene is decomposed into Hydrogen. All these phenomena of heating and burning can be used as the basis for the classification and identification of plastics for album printing. During the test, use tweezers to burn the plastic pieces in the flame, observe the burning situation, and determine which plastic it belongs to.
②Recognition method of tearing of plastic composite film for album printing. The composite film was opened with a razor blade and torn by hand. If it is easy to tear, it is a cellulose film. Such as not being easy to tear in a polypropylene film. If it is difficult to tear, it is a polyethylene film, oriented nylon film, or polyester film.