CS274365B1 - Flux filling on snpb base for tube solders - Google Patents

Abstract

The flux filling of soft tubular solders based on SnPb is intended especially for soldering in the form of a tubular solder in connection with the suitable and common source of light. In the form of a solution, it can be well utilized for soldering e.g. of plates of printed circuits by a fluid wave of solder or for machinery (plumbing) soldering of common materials. The principle of the flux filling lies in the fact that the main component is based on esterified high-molecular alcohol, polyethylene glycol in combination with phosphoric acid and ethylene oxide. It improves flow of solder, has higher thermal stability, broader use, and it is non-toxic for soldering.

Description

Cnl'b low-voltage solder cartridges based on SnPb-based soft-solder cartridges are intended, in particular, for soldering in the form of tubular solder in conjunction with a suitable and common heat source. soldering, for example, printed circuit board by liquid wave solder and in solid form or in the form of a solution, it is also possible to use mechanical soldering of common materials.

The essence of the stuffing consists in the Torah that the gaseous component is based on the esterification of a high molecular weight alcohol, polyethylene glycol, in conjunction with phosphoric acid and ethyleneoxydora.

It improves solder spacing, higher thermal stability, wider use and is non-toxic when soldering.

274 365 (11) (13) 31 (52) Int. CI?

25 £ 25/353 3 23 K 35/362

CS 274365 Bl

-IN

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flux filler of SnPb-based soft tube solders for soldering in electrical engineering and electrical engineering. as well as mechanical soldering.

So far, flux fillers of SnPb-based tube solders or separate fluxes are known, consisting generally of a pure rosin or of a mixture of a rosin with chemical compounds, in particular increasing the efficiency of the purification process during soldering or brazing. improving diffusion conditions. These chemical compounds and their products also have negative side-effects: increasing the corrosive effect on the solder joint parts, the cost of cleaning it from the flux residues, the hygienic and ecological defect of the cleaning agents as well as its own constituent, rosin, or unwanted effect on life processes involving other unacceptable chemicals (reon).

The essence of the flux filling of soft tube solders, resp. It consists of polyethylene glycol in an amount of 10 to 80% by weight, phosphoric acid in an amount of 1 to 10% by weight, and ethylenozyd in an amount of 10 to 89% by weight.

The main advantages of the flux filling of soft tube solders, resp. The main component of the flux is based on an esterified high molecular weight alcohol, which assumes the function of surfactants, detergents and a foaming agent, and in conjunction with phosphoric acid with ethylene oxide as activators, as well as the surface protection of soldered material and solder and detergency support function. main component.

It eliminates the technological complexities of the production of fluxes of the previously known concepts, reducing economic demands. Flux filling. respectively. the flux has a high stability, the concentration of its exhalates under technological heat is not toxic. It is washable with water, or because of corrosion, its presence on the solder joint is negligible and harmless. It's non-corrosive.

In one case, the tests were carried out with fluxes, respectively. % fluxes in an amount of 10 to 80 wt. % polyethylene glycol, 1 to 10 wt. % phosphoric acid and 10 to 89 wt. of ethylene oxide.

The solder itself had the composition Sn6OPb4O, respectively. Sn63Pb37. The tests concerned the flux filler in the solder tube, respectively. a separate flux in the form of a solution using a liquid brazing solder, respectively. use under mechanical (plumbing) soldering conditions. The working temperature was 195 to 280 ° C. The technologies used were liquid soldering iron.

Using known rosin-based fluxes (e.g. FB 12-11) an average flow rate of 5 = 120 mm ³ (Cu) of E = 80 mm ³ (Ms) was achieved. Corrosion of flux residues after brazing: conductivity ^{1 of} aqueous extract 340 to 470 us.cm ^-1 , the amount of soluble acids in the water ranged from 14 to 78 mg.l "\ cleanliness of printed circuit boards ranged from 0.60 to 1.05 ug NaCl.cm ^- '. Water Solubility: The fluxes tested were insoluble. Hygienic evaluation: smoke - fluxes give decomposition toxic toxic pyrolytic products of aldehyde character, the decomposition starts already at 180 ° C.

When using flux filler, resp. According to the present invention, an average flow rate of E = 385 mm (Cu) and E = 172 mm (Ms) was achieved. The corrosion of the flux residues after soldering was as follows: conductivity ^{1 of} aqueous leachate 182 to 195 us.cm ^- \ quantity of soluble acids in water 1.28 mg.l ^-1 , the purity of printed circuit boards reached values lower than 0.5 µg NaCl.cm ^{- 2} . Water solubility: very good from 10 ° C. Hygienic evaluation: reduced smoke density (approx. 50% of the value of known fluxes and fluxes), stability up to 325 ° C. The mechanical strength was fully maintained.

CS 274365 Bl

The electrical conductivity of the connections was fully maintained or improved slightly (0 0.2%).

The invention is applicable to all types of soft soldering (also as an additional solder), but in particular as a flux filler for soft tube solders, for the full range of solder types and their applications.

Claims (1)

OBJECT OF THE INVENTION SnPb-based flux cores for soldering in the electronics and electrotechnical industries in various ways, characterized in that it consists of polyethylene glycol in an amount of 10 to 80% by weight, phosphoric acid in an amount of 1 to 10% by weight. and ethyleneoxyde in an amount of 10 to 89 wt.