At present, there are more and more counterfeit plastic products on the market, which has become a topic of concern. There are a wide range of counterfeit plastic products ranging from pharmaceutical packaging, medical equipment, sporting goods, electronic products, and parts for automobiles and spacecraft. Not included. Counterfeit products cause genuine goods manufacturers to suffer economic losses; damage to the reputation of brand-name products, increase the cost of maintaining product reputation and quality assurance, and sometimes cause harm to consumers. The deeply damaged product processing manufacturers and resin raw material manufacturers are jointly seeking for some product authentication and verification technologies to solve the problem of anti-counterfeiting identification of products. These anti-counterfeiting technologies include microparticle identification, recognizable pigments and dyes, radio frequency identification tags, holographic patterns, and laser marking systems for making wear-resistant etched bar codes. 1, particle identification The purpose of the development of microscopic markings was to help trace the origin of explosives in the event of a terrorist attack. However, they are now widely used to track and identify the authenticity of plastic products. The most typical microparticle identifications are those containing a specific resolution function of the color bar pattern or containing a special chemical composition of the polymer particles, these particles can be pre-mixed with the thermoplastic before molding. The diameter of the microparticles is less than 50 micrometers (equivalent to the size of the bacteria) and about 600 micrometers (equivalent to the size of the salt particles) is not the same. These microparticles are inert substances that normally do not react chemically and can withstand the high temperatures that occur during molding without damage. By transforming the combination of numbers, models, and colors on each particle or changing the chemistry of the particle surface, millions of unique and unique coding mixtures can be produced. Because the resin contains encoded microparticles, manufacturers and product information can be identified using special reading devices. Marked particles are often pre-mixed with the plastic powder so that it can be used for molding or condensed, and can be molded by diluting it during processing. Color micro-labels on injection-molded, extruded or rotomolded plastic parts can be clearly identified by microscopy or pattern-resolver scanning. Some manufacturers make the logo fluorescent or magnetic, so that the authenticity can be easily distinguished by using an ultraviolet irradiator or a magnetic scanner. 2, pigment and dye additives Another way to identify whether or not plastic parts are manufactured is to mix the plastic parts with pigments or dyes. Spectrometers are used to analyze the exposed areas and the ultraviolet region, and those pigments or dyes show a unique pattern. Even if counterfeiters use extremely similar colors on their plastic products, they cannot obtain the same spectrum as genuine ones. One of the most recent anti-counterfeiting technologies was the use of "color changing" pigments. These additives contain a multilayer polymeric light-reflective coating that is applied around a piece of reflective aluminum chip, allowing the color of the plastic to change with viewing angle. The change of color, for example, from red to green, is due to the fact that light waves reflected from different pigment layers are disturbed by the angle. Color-changing pigments produce significant aesthetic effects on plastic consumer products, and because these effects are not easily cloned, they also have anti-counterfeiting features. Color-changing pigments can be mixed into a variety of resins such as PC, PP, HDPE, PET, ABS, thermoplastic PU, cellulose acetate, and PA12. The weight ratio of the color changing pigment in the resin is usually between 0.2% and 0.4%, and can be processed by standard processes such as injection molding, extrusion blow molding, thermoforming, calendering, extrusion film and in-mold decoration. 3, RF resolution / RFID tags Another method to identify plastic parts is radio frequency identification (RFID) tags, which are pre-set miniature tags that emit radio signals in plastic parts. The signals containing the plastic component code information are received by the radio receiver and forwarded to the relevant computer. RF-resolved tag technology uses micro-emitters (radio transmitters) mounted on semiconductor chips to store data. Most tags have both reading and input data capabilities. When the tag is powered on, it is sensed by the electromagnetic field emitted by the radio receiver antenna and the receiver can read out the data information on the tag. RFID tags are often glued to plastic parts in the form of adhesive labels. But for a long time these tags are easily removed. The latest RFID tags are embedded in plastic parts during injection molding. The most common practice is to embed these tags on plastic boxes and trays. Despite washing, collision or friction is not easy to escape. Only a few micron size RFID tags are available to track the true source of food, medicine, and other items packed in plastic containers that come in through various supply channels. The packaging date of each shipment and other information of the shipping port and packaging materials are encoded into the label. After the goods arrive at the port of destination, the information in the tags can be read out with the instrument. In the plastic packing box, any goods without any label or without any information on the label may be counterfeit goods. 4, holographic pattern The three-dimensional holographic pattern that is not easily copied by counterfeiters has been commonly used in the anti-counterfeiting of credit cards, currency, and bills, and its safety performance has generally been recognized. Holographic patterns are also printed on plastic packaging to distinguish brands and protect products from counterfeiting. Plastic packaging films printed with holographic patterns are generally PVC, PET, OPP, and BOPP films. Printing a holographic pattern onto a plastic film requires several passes. Before printing a holographic pattern, it is often necessary to first apply a relief coating to the finished film. Toray Plastics (USA) recently introduced a PET film that can be directly printed with a hologram without the need for additional coating. It is said that the advent of this product has accelerated the commercialization of new holographic designs. Another invention is a new technology for printing holographic patterns onto plastic parts during injection molding. Before the hologram pattern template is set in the mold, plastic parts with holographic patterns can be injected. The advantage of this type of holographic patterning technique is that it saves the processor time and money. Because they do not need to spend additional time and processes to print holograms. Holographic patterns can also be printed on shrink wraps. Watlord Holoprotec of the UK can provide a PVC shrink sleeve with holographic stripes. This sleeve is a continuous flat hose that can be cut into sections or shaped into special shapes and can be used for packaging beverages, alcohol, condiments and cooked foods. Using lasers to print dates, bar codes, codes, logos, and patterns onto plastic parts, are widely used for inventory control, inventory reduction, and product differentiation. Not only that, because the laser marking will not produce interference signals and will never be tampered with, it can also be used for product anti-counterfeiting. Laser bar codes can not only help track and monitor the products in the supply chain, but also help packagers and retailers to remove items without identifying codes from the warehouse. Counterfeiters cannot obtain the same equipment and materials that mark genuine products, so it is almost impossible to duplicate the same laser markings or decorative patterns. Laser markings are more legible than other methods, such as ink jets and primers. Because laser beams can be easily programmed in computers, laser markings are more flexible and versatile. Of course, the use of laser marking also has its limitations, that is, the equipment is expensive and there are few colors available. However, the laser equipment has more industrial production capacity, and the unit production cost has been declining. At the same time, new resin additives have been introduced. This makes the range of colors that can be used for laser marking larger, no longer limited to the usual black, white, Brown and gray match. Recently, a two-dimensional laser bar code has been newly developed for anti-counterfeiting, which consists of a large number of lines arranged on two adjacent edges of a box and pattern marks and spaces arranged on two other adjacent edges. Compared with ordinary bar codes, 2D bar codes can edit more data on plastic parts, and the bar code size is smaller. Two-dimensional bar codes are also more wear-resistant than traditional bar codes. In plastic anti-counterfeiting applications, 2D laser bar codes are more commonly used in electronic components, medical devices, pharmaceutical packaging, and perfume bottles.
5, laser marking system
Source: Foreign Plastics
Latest progress in anti-counterfeiting technology for plastic products