SU1303341A1 - Flux for soldering and tinning - Google Patents

Abstract

The invention relates to the field of soldering, in particular to the composition of the flux for soldering and tinning during the installation of assemblies and parts of electronic equipment. The aim of the invention is to increase the activity of the flux and reduce the corrosive effect on the melted material. The flux contains components in the following ratio, wt.%: Citric acid 5-8; triethanolamine 1-3; ethyl alcohol else. The flux is non-toxic, has a high cleansing effect and activity, ensures the growth of the solubility of the solder and its penetration into the gap. Removal of flux residues is not required, since they do not degrade the electrical parameters of the products. 2 tab. oo o GO so 4

Description

five

11JU334

The invention relates to the field of aiki, in particular, to the composition of the flux of soldering and tinning during the installation of assemblies and parts of electronic equipment .5

The aim of the invention is to increase the flux activity and reduce the corrosive effect on the melted material.

Flux contains components in the following ratio, wt.%:

Citric acid 5-8 Triethanolamine 1-3 Ethyl alcohol Remaining Flux is a clear, pale yellow liquid. The initial state of all components, except citric acid, is clear liquids. Citric acid is a white powder. To prepare the flux, a solution of citric acid in ethyl alcohol is preliminarily prepared, then Triethanolamine is added to the solution. The resulting mixture is stirred again.

Flux compositions are given in table.1. The proposed flux is non-toxic, it allows to improve working conditions, since it does not have an irritating effect on the mucous membranes of the respiratory tract of the performers during soldering and therefore can be used both for group, automated and mechanized, and for manual soldering. Flux has a high cleansing effect and activity, provides. Increased flowability and penetration of solder into the gap. Its practical application is providing20

25

thirty

35

Component Name

The number of ingredients, wt.%, In the composition

Citric acid3, 5

Triethanolamine 1.0

Ethanol

95.5

five

0

five

thirty

35

em quality solder base (copper, nickel) and noble (gold, silver) metals. In this case, the number of defective rations in the group method of soldering is reduced by 5 times. Flux residues are easily and completely removed with cold water.

Properties are presented in table 2.

Containing citric acid in the flux reduces the surface tension of the molten solder, increases its flowability, improves the wettability of the metal with it, thereby ensuring a higher soldering quality. Citric acid in the composition of the flux almost completely burns out in the soldering zone. As a result, the corrosive effect of the flux on the material to be fed is almost completely excluded.

Removal of flux residues in consumer electronics products is not required, since flux residues do not impair the electrical parameters of the products.

Claims (1)

Invention Formula Flux for soldering and tinning, containing citric acid, triethanolamine and ethyl alcohol, characterized in that, in order to increase the activity of the flux and reduce the corrosive effect on the melted material, it contains components in the following ratio, wt.%: Citric acid 5-8 Triethanolamine 1-3 Ethyl alcohol Else Table .6,5 2,0 92 89 9 3 88 The coefficient of spreadability solder POS 512.31 2.47 2.53 2.58 2.61 The quality of soldering on the prepared copper surface in a group way,% of quality rations 83 98 98 98 99 Soldering quality on un-prepared copper surface of printed circuit boards,% of high-quality rations Soldering quality of nickel-plated ERI terminals,% of high-quality rations Irritant effect on the respiratory system of working solders Not Pausing of ERI terminals with tin-lead coating, stored for 6 months before soldering,% of rations of quality Editor I.Rybchenko Compiled by L.Abrosimova Tehred L. Oleynik Proofreader S. Cherni Order 1252/15 Circulation 976 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Manufacturing and printing company, Uzhgorod, Projecto st., 4 89 93 96 96 83 87 91 94 Not Not Not there is 95 98 100 100