CN1056795C - Solid soldering agent used in soldering tin rod - Google Patents

Abstract

The invention relates to a no-cleaning solid flux for solder wire and a preparation method thereof. The flux is composed of rosin derivatives, thermosetting resins, curing agents, active agents, dispersants, etc. in a certain proportion, and the preparation process is to The thermosetting resin and the curing agent are mixed and heated in proportion to make them evenly mixed, and then other components are added into another container, heated and mixed evenly, and after a little cooling, the two are put into the same container, and the product of the present invention is obtained after mixing evenly. Using the solid flux of the invention can make the printed board have high insulation resistance, no corrosion, and the solder joints are clean after welding without cleaning.

Description

What be used for solder stick exempts to clean solid flux and preparation method thereof

The present invention relates to a kind of be used for solder stick exempt to clean solid flux, be used for the electronic product welding.

In the past, in the welding of electronic product, all adopt the colophony type scaling powder.The used colophony type scaling powder that also mostly is in solder stick.In welding process, rely on the oxide-film on the activating agent removal substrate in the scaling powder, make firm welding reliable.The colophony type scaling powder mainly is made up of rosin and halide, and is many with this scaling powder welding back printed board plate face residue, is corrosive, and for demanding electronic product, postwelding must clean.Cleaning used solvent is fluorine Lyons, and a large amount of dischargings in fluorine Lyons can cause the destruction of ozone layer, thereby have destroyed existent environment of people.

The objective of the invention is to develop a kind of be used for solder stick exempt to clean solid flux, change the composition of scaling powder in the prior art, make its not halide and common rosin, postwelding is residual few, is not with corrosivity, and very high insulaion resistance is arranged, simultaneously, postwelding need not clean.

The present invention development be used for solder stick exempt to clean solid flux, its composition is:

Rosin derivative 80%

Heat reactive resin 10%

Curing agent 0.5%

Activating agent 8%

Dispersant 1.5%

Its preparation technology is: at first with heat reactive resin and curing agent Hybrid Heating in proportion, resin and curing agent are mixed, the control heating-up temperature is no more than 110 ℃; With rosin derivative, activating agent and dispersant Hybrid Heating in proportion, until miscible, heating-up temperature is no more than 130 ℃ in another container; After the cooling, the heat reactive resin that obtains with the first step mixes, and promptly obtains exempting to clean solid flux slightly.

The advantage of solid flux of the present invention is to adopt compound resin to replace rosin.Compound resin comprises rosin derivative and heat reactive resin.In welding process, owing to stand about 200 ℃ high temperature, resin can solidify fast, forms thin film and covers the solder joint surface, and this layer film has good insulating properties and protection solder joint to avoid moisture attack, and therefore, postwelding printed board insulaion resistance height does not corrode.This solder flux does not use common rosin, and rosin itself easily be full of cracks and insulaion resistance shortcoming such as varies with temperature and alleviates greatly, and again because compound resin is heated and is difficult for the carbonization blackening, therefore, the postwelding solder joint cleans.

Another advantage of the present invention is that activating agent is not halogen-containing, forms and be to use two or more organic acid suitably to cooperate.This activating agent can keep welding active in than large-temperature range, and the postwelding residue is few, does not corrode.

The used resin of the present invention is a compound resin; wherein a resinoid is a rosin derivative; Foral for example; hercolyn D, consumption are 80% of solder flux amount, and another kind of resin is a heat reactive resin; heat reactive resin can solidify in welding process fast; form hard solid film, this film has very high insulaion resistance, and can protect solder joint to avoid moisture attacks.In the present invention, heat reactive resin can adopt bisphenol-a epoxy acrylate, phenolic aldehyde epoxy acrylate, urethane acrylate etc.The heat reactive resin addition is 10% of a whole solder flux amount, and use amount does not have the cured film effect very little, and the excessive resin solidification of use amount is incomplete, and postwelding printed board aridity is poor.The used curing agent of resin can be the 2-EAQ, benzophenone, and benzoyl peroxide, benzoyl dimethyl ketone etc., hardener dose is 1.5% of a solder flux total amount.

The used activating agent of the present invention is the organic acid activating agent, and the dependence organic acid is removed the oxide-film on the substrate, makes solder joint solid and reliable.The used organic acid of the present invention can be glutaric acid, adipic acid, decanedioic acid, salicylic acid, citric acid, hippuric acid etc.These organic acids can be used.Suitably cooperate, can reduce the vapourizing temperature of activator, reduce the postwelding residue.Activator level is approximately the 5-20% of solder flux total amount, and consumption welds poor activity very little, and the rate of spread is low, and consumption is too much, and postwelding is residual many, and insulaion resistance descends.Add a small amount of organic acid esters in the activator as dispersant, can increase the dispersing uniformity of organic acid in solder flux.

Be embodiments of the invention below

Embodiment 1

Foral 60

Hercolyn D 20

Phenolic aldehyde epoxy acrylate 10

Adipic acid 6

Citric acid 2

Dibutyl phthalate 1.5

Benzoyl peroxide 0.5

With heat reactive resin and curing agent Hybrid Heating in proportion, resin and curing agent are mixed, the control heating-up temperature is no more than 105 ℃.Simultaneously, in another container, with all the other component additional mixing heating, until miscible, temperature is no more than 130 ℃, and back, cold slightly back mixes with curable resin, obtains product.According to the every performance of GB9491-88 standard test be: the rate of spread: greater than 80%, content of halogen: 0, insulaion resistance: 1 * 1012 Europe, corrosion test: qualified.

Claims (6)

1. A no-clean solid flux for solder wire, characterized in that the composition of the solid flux is: Rosin derivatives 80%   Heat Curing Resin 10% Curing agent 0.5% Active Agent 8%                                     1.5% 2. A method for preparing the no-clean solid flux for solder wire as claimed in claim 1, characterized in that the method is: firstly heat the thermosetting resin and the curing agent in proportion to be mixed and heated, so that the resin and the curing agent are mixed Uniform, control the heating intensity not to exceed 110°C; mix and heat rosin derivatives, active agents and dispersants in proportion in another container until they are miscible, and the heating intensity does not exceed 130°C; after cooling slightly, obtain the same as the first step The thermosetting resin is mixed evenly to obtain no-cleaning solid flux. 3. The solid flux according to claim 1, wherein said rosin derivative is any one of hydrogenated rosin, maleic rosin, rosin glyceride or hydrogenated rosin methyl ester. 4. The solid soldering flux according to claim 1, wherein said thermosetting resin is any one of bisphenol A epoxy acrylate, novolac epoxy acrylate or urethane acrylate. 5. The solid flux according to claim 1, wherein the curing agent is any of 2-ethylanthraquinone, benzophenone, benzoyl peroxide or benzoyl dimethyl ketone A sort of. 6. The solid flux according to claim 1, wherein said active agent is any one of glutaric acid, oxalic acid, sebacic acid, salicylic acid or hippuric acid.