1. The function of LED chip lamp bead dispensing. Surface mount adhesives (SMA, surface mount adhesives) are used for wave crest connection and reflow connection. They are mainly used to fix the components on the printed board, usually by dispensing or The method of stencil printing is used to distribute to maintain the position of the components on the printed circuit board (PCB) and ensure that the components will not be lost during the transfer process on the assembly line. After the components are pasted, they are placed in an oven or reflow soldering machine to heat and harden. It is different from the so-called welding. Once it is heated and hardened, it will not melt if heated again, that is to say, the thermal hardening process of the patch adhesive is irreversible. The use effect of SMT patch adhesive will vary depending on the thermal curing conditions, the connected object, the equipment used, and the operating environment. When using, choose the patch glue according to the production process.
2. The components of LED SMD, lamp bead SMD glue Most surface mount glues (SMA) used in PCB assembly are epoxy resins (epoxies), although there are acrylics used for special purposes. After the introduction of high-speed glue dispensing systems and the electronics industry mastering how to deal with products with relatively short shelf life, epoxy resin has become a more mainstream glue technology worldwide. Epoxy resin generally provides good adhesion to a wide range of circuit boards and has very good electrical properties. The main ingredients are: base material (that is, the main high-molecular material), filler, curing agent, other additives, etc.
3. The purpose of the use of the LED patch lamp bead patch glue a. To prevent the components from falling off during wave soldering (wave soldering process) b. To prevent the components on the other side from falling off during reflow soldering (double-sided reflow soldering process) c. To prevent Component displacement and standing position (reflow soldering process, pre-coating process) d. Marking (wave soldering, reflow soldering, pre-coating), when printed boards and components are changed in batches, use SMD glue for marking .
4. Classification of the use of LED patch lamp beads patch glue a. Dispensing type: Glue is applied on the printed circuit board through a dispensing equipment. b. Squeegee type: Glue is applied by means of squeegee printing on steel mesh or copper mesh.
