51 results about "Ionic contamination" patented technology

The invention relates to soldering flux for lead-free solder and a preparation method of the soldering flux. The soldering flux comprises, by mass, 2.0-4.0% of activating agent, 0.05-0.5% of surfactant, 0.4-1.0% of film-forming agent, 18-30% of cosolvent, 0.1-0.4% of corrosion inhibitor and the balance deionized water. The soldering flux is free of rosin and less than 3% in solid content, so that solid residual quantity is less during soldering, ionic contamination degree is low, and cleaning is avoided after soldering. By using the deionized water as solvent, the water-soluble no-clean soldering flux is colorless, transparent, free of pungent smell, easy in raw material getting approach and low in cost. Activating components in the soldering flux are halogen-free, so that insulativity of a soldered circuit board is improved; by the aid of the film-forming agent, a dense protecting film is formed on the surface of the circuit board after the film-forming agent is subjected to a soldering procedure, and accordingly, electromigration of soldered residues is lowered, and insulation stability of the circuit board is improved effectively; and harm caused when organic soldering flux is used for soldering can be reduced, and the soldering flux meets the environment-friendly requirements.

The present invention is directed to a sorbent comprising a disordered polyvalent metal oxide on the surface of an inert substrate. The substrate can be a layered silicate, such as vermiculite, an aluminosilicate such as montmorillonite, or a nonlayered silicate such as a zeolite. The sorbent removes ionic contaminants, such as arsenic, from process streams.

The invention relates to a soldering flux for welding in the electronic industry, in particular to a no-clean and halogen-free soldering flux. The soldering flux consists of organic solvent, abietic resin and derivate of the abietic resin, synthetic resin surface active agent, organic acid activated agent, anticorrosive agent, latent solvent and film forming agent. The soldering flux has the advantages of transparency, no environmental pollution, no penetrating odor, little smoke fume, shining welding spot, strong wetting power, excellent weldability, few residues left on the plate surface after welding, clean plate surface, low ionic contamination, unnecessary cleaning after welding and high surface insulation resistance, and conforms the environmental protection requirements, meets the no-clean requirement of a printing component plate and has stronger market competitiveness.

The invention belongs to the field of welding materials, and particularly relates to a halogen-free, low-residue, high-impedance and cleaning-free flux, which comprises the following components: 2-15wt% of activator, 0.05-2wt% of dispersing agent, 0.5-4wt% of film-forming agent, 0.1-4wt% of additive and 75-97.35wt% of solvent. Compared with the prior art, the flux has the advantages that the expansion ratio of the flux is higher than 80% of the standard, the flux is moderate in weldability and halogen-free, ionic contamination is at the highest I grade, the flux is applicable to high-reliability electronic products, the surface insulation resistance of the flux is at a 1010 grade after a copper mirror corrosion test, and the flux has the advantages that the flux is high in insulation impedance, high in insulation resistance, low in electric leakage risk, low in solid content, environment-friendly, clean and cleaning-free, residue is less, a post-weld board is tack-free and the like.

The invention provides a non-halogen cleaning-free soldering flux, which comprises the following compositions in percentage by weight: 0.5 to 5 percent of stannous oxalate, 0.5 to 20 percent of organic acid activator, 0.1 to 1 percent of surfactant, 0 to 3 percent of cosolvent, and the balance of solvent. Because of adopting the stannous oxalate as an activator, and having synergistic action with the organic acid activator and no halogen, the soldering flux has the advantages of no irritant odour, less smoke, no environmental pollution, strong wetting power and excellent weldability. When the soldering flux is used for welding, a printed package board has less solid residue, clean layout and low ionic contamination, and needs no cleaning after the welding; and the printed package board has high insulation resistance after the welding, which can meet the cleaning-free requirement of the printing package board.

A hard disk drive inner part formed of a resin which exhibits well-balanced low outgassing properties, ultrasonic cleaning resistance, low ionic contamination properties, low particulate contamination properties, repeated removability, heat resistance, specific gravity, and water-absorbing properties. The hard disk drive inner part includes a resin composition which includes a polyphenylene ether resin (A).

The invention relates to a weakly acidic copper polishing solution applicable to low downforce and belongs to the technical field of microelectronics auxiliary materials and ultra-precision machining processes. The polishing solution comprises abrasive particles, an oxidant, deionized water, an inhibitor, a complexing agent and a silica sol stabilizer; and the pH value of the polishing solution is 5-7. By adopting the weakly acidic copper polishing solution, high removal speed and high surface accuracy of copper polishing are achieved under the condition of low downforce (below 1 psi) and the surface of polished copper has less residues of abrasive particles and ionic contamination.

The invention discloses an environment-friendly soldering tin material and a preparation process thereof. The environment-friendly soldering tin material comprises 95.5%-97.5% of tin, 0.5%-0.9% of copper, 0.06%-0.08% of nickel, 0-0.1% of lead, 0-0.1% of silver, 0-0.1% of bismuth, 0-0.001% zinc, 0-0.1% of antimony, 0-0.03% of arsenic, 0-0.02% of ferrum, 0-0.001% of aluminum, 0-0.002% of cadmium and1%-4% of a soldering flux. The preparation process comprises the first step of pre-treatment of the raw materials. According to the environment-friendly soldering tin material and the preparation process thereof, the soldering tin material prepared from tin, copper, nickel, lead, silver, bismuth, zinc, antimony, arsenic, ferrum, aluminum, cadmium, aluminum, cadmium and the soldering flux is highin purity and environmentally friendly, welding defects can be effectively avoided when the soldering tin material is used, and the welding effect is improved; and meanwhile, the soldering flux is added into the soldering tin material in the preparation process so that ionic contamination can be avoided in use, emission can be conducted without special treatment, and the environmental friendlinessrequirement is met.

A laminar material for cleaning the anion-polluted water by removing the anions (F ions, arsenous radicals, or arsenic radicals) is prepared through proportionally dissolving Mg (or Zn) source and Al source in water, dissolving alkali and anions in water, quickly mixing them, stirring for 48-144 hr, pump filtering, water washing and baking to obtain white powder.

To reduce ionic contaminants on printed circuit boards that are at least partially covered with a solder resist mask and are provided with top layers on the copper structures, an aqueous cleaning solution is used, which contains at least one ethanolamine compound and/or the salt thereof, at least one alcoholic solvent and, at need, at least one guanidine compound and/or the salt thereof.

Insulation compounds for medium-voltage power cables and methods for making same are provided. The compound can include a polymer comprising ethylene, one or more C₃-C₈ alpha olefins and, optionally, one or more dienes, and one or more metal oxides not based on lead or zinc.

The invention discloses a cleaning process and a cleaning device for removing ionic contamination from a PCB (printed circuit board). The cleaning process includes following flow paths of acid pickling, first multistage overflow water cleaning, ion removal cleaning, second multistage overflow water cleaning, drying and cooling. The cleaning device comprises a running roller conveyor belt used for conveying the PCB, wherein an automatic board placing machine is connected with the head end of the running roller conveyor belt, an acid pickling segment, a first multistage overflow water cleaning segment, an ion removal cleaning segment, a second multistage overflow water cleaning segment, a drying segment and a cooling segment are sequentially arranged on a passing path of the running roller conveyor belt, and an automatic board collection device is connected with the tail end of the running roller conveyor belt. The cleaning process and the cleaning device for removing the ionic contamination from the PCB improve cleaning effects of removing the ionic contamination from the PCB, and save labor cost, and the cleaning device can perform accurate parameter control, and the cleaning effects of the cleaning process for removing the ionic contamination from the PCB are further improved, and then ionic contamination degree of the PCB is further reduced, and furthermore PCB industry development is promoted.

The invention discloses a method for removing water and chloride ions in fluoroethylene carbonate, which comprises the following steps of: removing water by using an alkaline drying agent until the water content is less than or equal to 30ppm, so that no metal cation pollution is generated after the reaction, removing the chloride ions, and dynamically cooling and crystallizing, so that the obtained crystal is uniform in size and can be prevented from being adhered to the wall in a large area; the method is easy to operate in the subsequent filtering process, heating is not adopted in the whole water removal process, operation is easy and convenient, and the problems that a traditional heating distillation method is large in energy consumption, tedious in step, low in efficiency and high in water content are solved.

The invention provides a process for advanced treatment of coking wastewater and coupled fluorine ion removal. The process comprises the following steps: allowing biochemical effluent of the coking wastewater to enter a coagulation tank 1# from a raw water tank, adding 300-600 mg/L of a BH type advanced treatment agent into the wastewater, then performing stirring reaction, and then allowing the wastewater to enter a coagulation tank 2#, wherein the BH type advanced treatment agent is a composite agent which mainly comprises, in percentage by weight, 5-60 wt% of carbon powder, 2-50 wt% of a cyanogen removal agent and 20-60 wt% of a coagulant; adjusting a pH value in the coagulation tank 2# to 6-7, then adding a fluorine removal agent, carrying out sufficient stirring and reacting, and then allowing the wastewater to enter a coagulation reaction tank 3#, wherein the main component of the fluorine removal agent is calcium chloride, and the dosage of the fluorine removal agent is 900-2000 mg/L; adding 0.1-0.3% of polyacrylamide into the coagulation reaction tank 3#, carrying out slow stirring and uniform mixing, and allowing the wastewater to enter a sedimentation tank; and enabling solid to be formed through flocculation and sedimentation in the sedimentation tank, conducting solid-liquid separation, and allowing the treated wastewater to enter an effluent trough. The removal process disclosed by the invention is suitable for removing pollution factors such as low-concentration COD (Chemical Oxygen Demand), cyanide and fluorine ions in the wastewater and is a practical and simple agent treatment process.