The hottest printing technology is emerging in rad

Printing technology is emerging in radio frequency identification

in recent years, radio frequency identification (RFID) technology has developed significantly. Before this period, the lack of production standards and infrastructure to support different RFID applications called into question this innovative technological starting point

however, due to the persistence of RFID developers, the production system has made a breakthrough, and the development of supply channels supports the manufacturing of RFID. At present, most RFID applications have been standardized, and the market of these products, such as the number of companies producing them, has increased significantly. Among these companies developing the RFID market, they are all enterprises with industrial printing background, especially those with electronic equipment printing experience. Companies using other printing methods have also entered many aspects of RFID manufacturing. In this article, we focus on what RFIDs is and how it functions. We will also figure out how to prove that the plate printing 1 generally needs to be replaced after more than 3 to 5 years). The lubricating oil is mobilgear632 brush and other printing technologies, which are suitable for printing the key component of RFID labels and trademarks antenna

rfid principle

basically speaking, the production of RFID technology is to make the process of identifying and tracking products simple, fast and accurate. Other benefits and capabilities of RFID trademarks and tags include the following:

● protect the authenticity of products

● protect products against theft

● control product inventory at retail outlets, warehouses, libraries, etc

● control the entrance to buildings, parking lots, roads and other places

● improve data processing speed and reduce its cost by preventing errors in the process of data input

before RFIDs, bar codes on product packages and magnetic stripes on Banking and credit cards were the main ways to identify and track products and transactions. To obtain the data on the bar code or magnetic stripe, we need to scan the bar code, magnetic stripe or card with the readout device, and we must manually place the product or card in the readout device, which will lead to the delay of data processing. We have experienced such delay at the airline ticket counter and the checkout of the local supermarket

rfid technology automatically prompts the data of products or accounts, and there is no direct contact between RFID tags, trademarks or cards and reading devices. RFIDs react to magnetic radiation by returning the data attached to the product or card to the readout device. In addition, the data stored on the RFID trademark can be updated or changed. RFIDs will not completely replace all bar codes and similar systems, but will become the main way of product identification in the future

whether it is used as a label fixed on the product or embedded in a credit card or banking card, the structure of RFID label is basically the same. This tag will have an RFID pulse transmitter, which has a chip attached to the antenna. This antenna is actually a simple coil that generates magnetic induction or voltage

data exchange occurs between the RFID tag and the antenna of the reader/writer, and the reader/writer is connected to a computer. The following distribution describes how RFID technology works:

1 The passive RFID tag moves in the electromagnetic field of the reader

2 . This tag receives the signal from the reader to activate the trademark

3. The tag reacts by transmitting the data stored on the transmitter chip to the reader

4. The reader transmits the received data to the host computer. The reader can also provide new data for the tag, rewrite existing data, or invalidate the tag

the important thing that RFID tags are superior to bar codes is that they can be read without the reader's observation line by line. Unlike bar codes, RFID tag positioning does not need human assistance, so the process of reading tags can be carried out automatically

another advantage of RFID tag is that the chip on the RFID transmitter is a dynamic data carrier, which means that data can be read from and written to the chip. Since the data is exchanged through electromagnetic radiation, multiple RFID tags can be read at the same time

at present, RFID tags are increasingly used in logistics and supply chain management, food industry, medical care and pharmaceutical industry, library, entrance and exit management and toll collection, air baggage handling, livestock identification, document tracking, product identification or anti-counterfeit products through postal and express services. In order to prevent clothing counterfeiting and theft, some companies even print rfid antennas directly on textiles

rfid tag types

rfid tags are divided into two types, namely passive and active. Passive RFID tags need to be activated by the reader system before transmitting the data they carry. The active RFID tag is equipped with a battery, which enables the trademark to transmit signals independently. This article only focuses on passive RFID tags, which are the most commonly used

the antenna of a passive RFID tag can produce inductive or capacitive signals. Induction antennas can transform magnetic fields into electrical signals or other forms. These antennas look like winding coils. The other is capacitive antenna, which is not sensitive to electromagnetic energy, but only sensitive to electrical signals. Capacitive antenna can be distinguished according to the shape of its dipole

the frequency of electromagnetic radiation determines the reading distance supported by the label. The minimum reading distance required for data collection is the main factor affecting the design of rfid antennas for specific applications

rfid tags can be based on some frequency bands, such as low frequency (LF), high frequency (HF), ultra-high frequency (UHF after the completion of all required data collection) and microwave (see Table 1). The distance between RFID trademark reading and writing is 10 ~ 500 cm

l F antenna supports a frequency of 125 kHz. The antenna consists of copper coils wound more than 200 times. This antenna is used for a relatively short reading distance of no more than 50 cm. Common applications of LF tags include entrance and exit management (i.e. gate entrance/security card) and identification of livestock and livestock

h f tag is equipped with an antenna composed of 4 ~ 6 copper coils, which is sensitive to the frequency of 13.56 MHz. The maximum reading distance supported by this type of label is 1 m. HF tags can be used as "smart cards", such as acceleration signal-to-noise ratio, in band and out of band acceleration total root mean square ratio, reading cards issued by the library, and baggage tags in aviation baggage handling systems

uhf tags are sensitive to the frequency of 862 ~ 950 MHz, and the reading/writing distance is more than 5 m. In the United States, the UHF standard frequency is 915 MHz. Different frequencies can be used in other parts of the world. A large reading distance requires a dipole antenna. Such labels enable postal and courier services to determine the nature of products stacked on shelves without checking each package. Such labels are also used for auto payment cards of car drivers

the reading distance of microwave RFID tag is about 1 m, which is sensitive to the frequency of 2.45 GHz or 5.8 GHz. Microwave tags are used for logistics. HF and UHF tags are the most widely used RFID systems. Such tags are mainly composed of three parts:

● antennas - silver, copper or aluminum antennas communicate with readers by transmitting and receiving data

● chip - the chip is installed on the antenna and stores data for transmission

● plug in - a plug-in is a combination of chip and antenna on the carrier chip. RFID plug-in can be fixed on adhesive tape or plastic sheet to play the role of label or trademark, or it can be installed on plastic card

making RFID antenna

making antenna is the beginning step of RFID production process. HF and uh frfid tag antennas can be made in the following three different ways:

● printed directly with silver conductive ink

● remove copper or aluminum on the laminate by corrosion (subtraction)

● coat with conductive medium and then electroplate (add)

various methods of making RFID antenna can be completed by printing. According to the required service time and characteristics of the antenna, it can be printed by flexographic printing, gravure printing and printing

direct printing: direct printing enables the antenna to be produced in one operation, while other methods require multiple steps. For direct printing, solvent based, conductive, silver polymer thick film (PTF) inks are used to print antennas on plastic or paper-based substrate materials. The UV ink used in this application is currently under development

h f antennas require relatively thick ink layer to achieve appropriate conductivity, so plate printing is the main technology for making these antennas. Plate printing is an ideal technology for producing thick ink layers. The thickness of the ink layer can be easily adjusted by converting to different number of wires. After printing, hot air drying connects the silver ions in the ink to form a circuit, the final antenna

in addition to PTF ink, there is also hot silver conductive ink. This kind of ink does not contain polymer binder, but contains conductive organometallic particles. These particles fuse together at high temperature. Antennas printed with hot silver conductive ink have better conductivity than those printed with PTF ink

uhf antenna is generally thinner than HF antenna, so other printing methods are more suitable for printing UHF antenna than plate printing. Flexo printing and gravure printing are much thinner than the ink layer printed, but it is enough for UHF antenna. These two printing methods are generally used for live parts with large printing volume

the printing speed of flexo printing and rotary gravure printing is 100 ~ 500 feet/m i n (30 ~ 150 m/min), and the speed of platform printing machine is much slower, so the platform printing machine is usually only used to print samples and live parts with a small number of prints. On the contrary, the printing speed of rotary printing is about 80 ~ 200 feet/min (25 ~ 60 m/min), which is in the prominent position between platform printing and flexo/gravure printing. Table 3 compares the performance of platform printing and rotary printing

rotary printing, flexo printing and gravure printing are excellent technologies for mass production of roll to roll rfid antennas. The print number of UHF antenna determines the most suitable printing technology. Generally speaking, compared with the single channel using rotary printing, two channels are needed to print the HF antenna using flexo printing and gravure printing. Since double channel production may involve registration problems, rotary printing has become the main method of making HF antennas of all sizes. It is also used to print short to medium print UHF antennas

subtraction: RFID antenna (sometimes called printing corrosion method) is made by subtraction. The substrate is a laminated part, which has a plastic (such as polyester) substrate and is covered with a 20 ~ 25 mm thick copper or aluminum film. The resist is printed on the composite metal surface by printing. The anti-corrosion film is in the shape of the positive figure of the antenna, protecting the metal below from corrosion agents. When corrosive corrosive agent is applied, the corrosive agent will dissolve the metal not covered by the anti-corrosion film. Then apply the film remover to remove the anti-corrosion film, and then make the antenna

addition: addition is also called printing electroplated sheet, which is similar to subtraction. Apply a thin layer (several microns) of conductive and catalytic ink on the plastic substrate, in the shape of the positive image of the antenna. This special ink contains metal particles. After printing, the printed material is electroplated. Copper is plated on the material and only attached to the pattern formed by the conductive ink. The electroplating process continues until the amount of copper deposited on the material reaches a certain thickness to make it have proper conductivity

the future of RFID Technology