Adhesive adhesive conductive film with a need to wear anti-static clothing, anti-static carbon fiber gloves

Welding has always been the most reliable way to provide low-cost electrical interconnection. Only in the past 10 years, only for the welding process and reliability of the doubts. Adhesive adhesive conductive film with a need to wear anti-static clothing, anti-static carbon fiber gloves into the welding industry, another trend. In the more advanced use of electronic devices welding, it is most concerned about the issue of three: First, should not heat the electronic components of heat damage, the second is bridging, the third is fatigue. There are many electronic devices that can not be heated but need to be connected. The bridge is when the centerline of the component leads is narrower than 25 mils. , The use of reflow soldering, for the surface mount circuit board, the bridge is a prominent problem. For the tape with automatic bonding (TAB) or reflow center distance of less than 3 mils, the yield and process there are a big problem. The fatigue problem of welding is always present. For surface mount (SM) circuit boards, fatigue problems are more pronounced because of the limited area required to improve the compliance lead length. In addition, welding there are more environmental and health problems.

Polymeric materials are conductive and antistatic adhesives (or adhesives) that are developed with virtually anti-static clothing, antistatic carbon fiber glove shoes and conductive coatings, especially with anti-static and antistatic rubber.

Conductive adhesives are generally composed of conductive fillers, adhesives, solvents, additives. Addition of conductive anti-static shoes materials are gold, silver, copper, nickel and metal alloys such as metal powder, carbon black, graphite and their mixed powder. From the price, environmental reliability, the actual effect of many considerations and analysis to use the most silver. To silver powder, for example, in order to obtain high performance, you need to fully control the size and shape of silver. The surface area of the spherical powder

Small, poor conductivity, usually 0.1 to 1 bucket m fine silver powder thickness is 0.1 um m below, or particle size of 1 ~ 10¨m dendritic powder is also representative of the filler. In addition, the distribution of particle size is also important. The same anti-static service to achieve a certain resistivity, the greater the surface area, the less the amount of filling.

The second component is an adhesive. It is in the anti-static shoes and sticky material at the same time, so that conductive filler material chain connection and conductive adhesive anti-static film has a stable physical and chemical properties of materials, according to the purpose of use and the required characteristics of the appropriate selection Of the adhesive. Conductive adhesive variety, according to the different types of conductive filler in the adhesive, the adhesive can be divided into silver, gold, copper and carbon-based adhesives. Commonly used anti-static shoes such as acrylic resin, phenolic resin, epoxy resin. Among the many adhesives, especially the best performance of epoxy resin. Epoxy resin has the following advantages: strong adhesion, anti-static clothing, high bonding strength. High cohesive strength, small shrinkage, dimensional stability. Resistant to high and low temperature and good chemical resistance, strong adaptability. Resistant to good media, so that the product electrical performance. Easy to modify, widely used. Easy to use. Blending good, can be cured with a variety of curing agent. Low toxicity, low harm.

The third component is a solvent. The solvent is used to improve the operability of the adhesive. In the bonding of the lead and other occasions, but in the case of surface bonding is best without solvent. Different good solvents should be used depending on the type of adhesive. In addition, factors such as the drying rate, the boiling point of the solvent used, and the like are closely related to the operability.

Japan uses a mixture of epoxy, phenol, acrylic, polyester, alkyd, polyurethane and silicone polymers. The adhesive must be dissolved in the selected solvent, otherwise the conductivity of the dry coating will be unstable. Select the solvent to take into account the dyeing conditions. In the case of a cold-dry adhesive, a high-speed volatile solvent is added to the slag printing. To avoid clogging, use high boiling solvents.

The fourth component is an additive. There are dispersants in the additive which can improve and improve the conductivity and dispersion of the filler. An additive that improves the clarity of the board. Can be mixed with the performance of the coating agent. A tackifier capable of increasing the adhesive strength. So that accelerated and uniform curing, curing agent and many other varieties. These additives are added to assist in the properties of the conductive adhesive. However, the addition of additives in a large amount reduces the conductivity of the adhesive, so it must be limited to a minimum to achieve the above properties of the above additives.