CN101003111A - Soldering flux in use for SnZn series solder with no lead, and preparation method - Google Patents
Soldering flux in use for SnZn series solder with no lead, and preparation method Download PDFInfo
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- CN101003111A CN101003111A CN 200710010114 CN200710010114A CN101003111A CN 101003111 A CN101003111 A CN 101003111A CN 200710010114 CN200710010114 CN 200710010114 CN 200710010114 A CN200710010114 A CN 200710010114A CN 101003111 A CN101003111 A CN 101003111A
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- scaling powder
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- rosin
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Abstract
A flux for improving the wetting and spreading performane of lead-free SnZn solder is proportionally prepared from rosin, surfactant FSN, benzotriazazole and absolute alcohole through proportionally dissolving said components in absolute alcohol in sealed state, and filtering.
Description
Technical field
The present invention relates to a kind of scaling powder, be applicable to of the soldering of Electronic Packaging field, be particularly useful for making the core wire of SnZn brazing filler metal welding wire and the scaling powder of SnZn brazing filler metal wave-soldering with the SnZn series leadless solder.
Technical background
The history in existing thousand of application of tradition tin lead (SnPb) solder is the main material of present electronic package interconnections.But lead and compound thereof belong to noxious material, bring bigger harm for human habitat and safety.Since anti-plumbous proposal HR25374 (US Congress), the S22637 and S2391 (United States Senate) proposition of the U.S., the various tissues in the whole world, scientific research institution and company release series forbidding motion, test assessment and environment-friendly products one after another.On February 13rd, 2003, European Union has announced " scrapping electric instruction " and " about ban use of the instruction of some harmful substances in electronic electric equipment ", and the Electrical and Electronic equipment that regulation was put on market after 1 day July in 2006 must not contain 6 kinds of harmful substances that comprise lead etc.Under the constraint and promotion of factors such as environmental requirement, the market demand, the unleaded great scientific and technical advanced subject and the systems engineering problem that becomes academia and industrial quarters of Electronic Packaging.
Because lead is very harmful to human body and environment, Research of Lead-free Solders and application worldwide have been subjected to great attention, have also obtained effective achievement both at home and abroad aspect Research of Lead-free Solders.Generally believe relatively have the brazing filler metal alloy system of research and use value to mainly contain: SnAg system, SnZn system, SnCu system, SnSb system, SnBi system and SnIn system etc. at present.Compare with other lead-free brazing, the SnZn solder has the following advantages: the fusing point of SnZn solder need not when being used for the Electronic Packaging industry existing equipment and technology are carried out big improvement more near the SnPb solder; The low production cost of SnZn brazing filler metal, and aboundresources; SnZn is that soldered fitting intensity and creep-resistant property etc. all are better than the SnPb eutectic solder.
But the shortcoming of SnZn brazing filler metal maximum is that wetability is poor, makes SnZn solder brazing difficulty.This has seriously hindered the application and the development of SnZn solder.Cause the reason of SnZn solder wetting difference to mainly contain 2 points: the one, the surface tension of Zn is bigger; The 2nd, Zn easy oxidation in brazing process generates the very high ZnO of fusing point, hinders sprawling of solder.In order to improve the wetability of SnZn solder, the researcher has launched number of research projects round the SnZn brazing filler metal alloyization, and existing result of study shows adds the wetability that elements such as Ce, La, Cu, In, Ag and Bi can improve the SnZn solder in the SnZn solder.Its reason is that these alloying elements can not only reduce the content of Zn element on the solder surface at the surface enrichment of SnZn solder, reduce the surface tension of solder, and can effectively avoid the Zn element oxidation in brazing process in the solder.But alloying is very little to the raising effect of solder wetting, is difficult to fundamentally improve SnZn brazing filler metal wetability.Therefore, if can develop a kind of scaling powder, improve the wetability of SnZn solder, improve the welding performance of SnZn brazing filler metal, enlarge the range of application of SnZn solder, this further exploitation and practical application to low cost and resourceful SnZn solder is very useful.
The present invention complies with world today's environmental requirement just, is the SnZn series leadless solder scaling powder that advances the unleaded engineering of electron trade to develop.
Summary of the invention
Purpose of the present invention and task are that will to overcome the SnZn series leadless solder wetability that prior art exists poor, the soldering difficulty, the deficiency that is difficult to extensive use, and a kind of a kind of SnZn series leadless solder scaling powder and preparation method thereof that can increase substantially SnZn brazing filler metal wetability and SnZn solder and Cu solder joint adhesion is provided, the spy proposes technical solution of the present invention.
A kind of SnZn series leadless solder scaling powder proposed by the invention, comprising: film forming agent, surfactant, corrosion inhibiter and solvent is characterized in that:
A) also comprise activator BiCl
3
B) the weight percent proportioning wt% of each composition is:
Activator: BiCl
30.05～6%;
Film forming agent: rosin 30-60%;
Surfactant: FSN0.1～1%;
Corrosion inhibiter: BTA 0.01～2%;
All the other are solvent: absolute ethyl alcohol.
A kind of SnZn series leadless solder proposed by the invention preparation method of scaling powder, it is characterized in that: preparation process is: the first step is by the percentage by weight of its each composition, with its BiCl
3, rosin, FSN, the BTA weighing is good, and puts into beaker; Second step added load weighted in proportion solvent absolute ethyl alcohol in the beaker, and sealing makes solid material fully dissolve at normal temperatures; The 3rd step was the scaling powder product after filtering out impurity with the filter of aperture 1.5 μ m;
Of the present invention being further characterized in that: described rosin is one or more combinations in natural rosin or Foral or newtrex or the disproportionated rosin; Surfactant FSN is the nonionic fluorine surfactant.
Optimal proportion for each composition of scaling powder is: activator BiCl
30.5%, film forming agent rosin 45%, surfactant FSN0.8%, corrosion inhibiter BTA 1.5%, solvent absolute ethyl alcohol 52.2%.
Activator is a most important components in the scaling powder, is the active material that to help the weldering ability and add in solder flux in order to improve.The activity of activating agent is meant it and scolder and materials to be welded oxide on surface chemically reactive so that clean metal surface and promotion wettability mainly have been the effects that raising substrate and solder activity help soldering.Activator is selected BiCl for use among the present invention
3This is because BiCl
3Instability when soldering, can with the Zn element generation displacement reaction on liquid solder surface, and generate simple substance Bi, simple substance Bi can be added in the solder as surface active element, and at the solder surface enrichment.At first Bi dissolves in the surface tension that solder can reduce solder, will improve the capillary element of solder as some results of study and arrange as follows by ascending order:
Sn＞Pb＞Ag＞In＞Bi when simple substance Bi is added in the solder as can be seen, can reduce the surface tension of solder, thereby improves the wetability of solder; Secondly, Bi is at the solder surface enrichment, effectively suppresses Zn element in the solder to diffusion into the surface, thereby avoided solder oxidized in the process of soldering.And surface tension is big and the easy oxidation of the Zn main cause of SnZn brazing filler metal wetability difference just, if can finely overcome them, then can improve the wetability of SnZn solder greatly.Select BiCl based on above reason the present invention
3As activator.BiCl
3Content reach 0.05% activation effect promptly arranged, too high as the spreading ratio that surpasses the 6%SnZn solder, solder joint is shapeless, and halogen content also improves thereupon.So BiCl in the described scaling powder
3Content be controlled in 6%, halogen content meets national standard.
Film forming agent can form the organic closely film of one deck after welding, protected solder joint and substrate, has anticorrosive property and good electric insulating quality.The material commonly used of film forming agent is a rosin, and rosin is simultaneously also as the matrix of scaling powder, because rosin has faintly acid and hot melt flowability, and has good insulation performance, moisture-proof, non-corrosiveness, avirulence and long-time stability, is few wlding material that helps.Rosin can be one or more combinations in natural rosin or the modified rosins such as Foral or newtrex or disproportionated rosin in the described scaling powder.Consider cost, natural rosin can meet the demands, as requires better to help the weldering effect, can select other several modified rosins except that natural rosin.Rosin content is lower than 30% in the scaling powder, and the diaphragm of formation is not enough to protect solder joint and substrate; As surpassing 60%, will exceed the solubility of solvent, make part rosin can not dissolve in scaling powder, can not bring into play due effect.
The effect of surfactant is to reduce the surface tension of liquid solder and by weldering metallic surface energy, strengthen wetability, improves and helps the weldering effect.Surfactant in the described scaling powder is selected FSN (non-ion fluorin surfactant), and its consumption is 0.1～1% of a scaling powder.As be lower than 0.1% effect that does not have a surfactant, because surfactant is not volatile, content surpasses 1% and easily causes the postwelding residual product too much, cleans difficulty.
The effect of corrosion inhibiter is to protect printed board and component down-lead, has protection against the tide, mildew-resistant, Corrosion Protection, has kept good solderability again.It is corrosion inhibiter that described scaling powder is selected BTA, and its consumption is 0.01～2% of a scaling powder.Be lower than 0.01% effect that does not have an inhibition as content, content surpasses 2% effect that easily influences other compositions of scaling powder.
Solvent is that the various solid constituents in the scaling powder are dissolved in together, makes it to become homogeneous phase solution.The characteristic of solvent requires: (1) all has fine solubility to various solid constituents in the scaling powder; (2) the volatilization degree is moderate under the normal temperature, volatilization rapidly under welding temperature; (3) smell is little, and toxicity is little.The solvent of this scaling powder is selected absolute ethyl alcohol, and absolute ethyl alcohol possesses above-mentioned characteristic, and low price, nontoxic, other compositions such as rosin, activator can be dissolved in together uniformly, favourablely is configured to liquid scaling powder.
Because the matching relationship of each composition of the present invention has been given full play to the effect of various compositions in the scaling powder, thereby obtain the SnZn solder and on the Cu plate, reached 76% spreading ratio, surpassed the spreading ratio of commercial scaling powder RMA soldering SnAgCu solder 68%.And the SnAgCu solder is the good lead-free brazing of wetability of generally acknowledging.And the solder joint light after the soldering, formability is good.
The specific embodiment
A kind of SnZn series leadless solder of the present invention is provided by following examples in detail with the concrete preparation program of scaling powder and preparation method thereof.
Embodiment 1
Certain Electronics Factory produces and utilizes reflow soldering process to produce two-sided assembling SMD, adopts the production of SnZn scolder, uses the common commercial scaling powder, and the scolder spreading ratio does not reach requirement.The SnZn series leadless solder scaling powder that utilizes the present invention to develop has obtained spreading ratio and has reached 75% wetting effect, has obtained qualified products, and the scaling powder proportioning of its application consists of:
BiCl
3 0.05％
Natural rosin 60%
FSN 1％
BTA 0.01%
Absolute ethyl alcohol 38.94%
Compound method: the first step is by its percentage by weight, with its BiCl
3, rosin, FSN, the weighing of phenylpropyl alcohol triazole is good, and puts into beaker; Second step added load weighted in proportion solvent absolute ethyl alcohol in the beaker, and sealing makes solid material fully dissolve at normal temperatures; The 3rd step was the scaling powder product after filtering out impurity with the filter of aperture 1.5 μ m.
Be to adopt the welding method of prior art to carry out during production, be about to SnZn solder sheet dip in get scaling powder of the present invention place paster with by between the weldering pcb board, process reflow welding stove heating soldering.
Embodiment 2
Certain Electronics Factory produces household electrical appliances circuit boards such as television set, radio, complies with unleaded requirement, uses the lead-free brazing welding wire instead, adopts the SnAgCu solder always.Because the SnAgCu solder is too expensive, make product cost high, so want to replace with this lead-free brazing cheaply of SnZn.Because the wetability of SnZn solder welding wire is relatively poor, can not guarantee the qualification rate of product with general RMA scaling powder.Through selecting the BiCl that contains that the present invention produces for use
3The SnZn series leadless solder with scaling powder after, the soldering effect can reach the quality of using the SnAgCu solder, and product cost is obviously reduced.The scaling powder composition proportion that it adopts is as follows:
BiCl
3 6％
Natural rosin 30%
FSN 0.1％
BTA 2%
Absolute ethyl alcohol 61.9%
Compound method is with embodiment 1.
During production, utilize scaling powder of the present invention to make the SnZn flux-cored wire, on common SnPb solder brazing equipment, can implement as the medicine core.
Embodiment 3
Certain Electronics Factory adopts Reflow Soldering to produce computer motherboard, adopts SnCu solder soldering paste always.Because it is SnCu solder brazing temperature surpasses 250 ℃, bigger to the wiring board damage.Therefore want to select for use fusing point low, low-cost SnZn solder.But because the wetability of SnZn solder welding wire is relatively poor, general RMA scaling powder can not make the wetability of SnZn solder bring up to satisfied degree.Through using the BiCl that contains of the present invention's production
3The SnZn series leadless solder with scaling powder after, the soldering effect can reach the quality of SnAgCu solder brazing, and has reduced production cost.The scaling powder that this product is selected for use, its composition proportion consists of:
BiCl
3 0.5％
Natural rosin 45%
FSN 0.8％
BTA 1.5%
Absolute ethyl alcohol 52.2%
Compound method is with embodiment 1.
During use, utilize general crest welder to implement.Scaling powder adopts with foaming or spray application all can.
Embodiment 4
This is the SnZn series leadless solder scaling powder that a kind of film forming agent is selected natural rosin and Foral combination for use, and its weight proportion consists of:
BiCl
3 1％
Natural rosin 30%
Foral 15%
FSN 0.8％
BTA 1.5%
Absolute ethyl alcohol 51.7%
Compound method is with embodiment 1.
The use of scaling powder is with embodiment 3.
Embodiment 5
This is the SnZn series leadless solder scaling powder that a kind of film forming agent is selected newtrex for use, and its weight proportion consists of:
BiCl
3 0.8％
Newtrex 45%
FSN 0.8％
BTA 1.5%
Absolute ethyl alcohol 51.9%
Compound method is with embodiment 1.
The use of scaling powder is with embodiment 3.
Embodiment 6
This is the SnZn series leadless solder scaling powder that a kind of film forming agent is selected disproportionated rosin for use, and its weight proportion consists of:
BiCl
3 0.8％
Disproportionated rosin 50%
FSN 0.8％
BTA 1.5%
Absolute ethyl alcohol 46.9%
Compound method is with embodiment 1.
The use of scaling powder is with embodiment 3.
Embodiment 7
This is a kind of SnZn series leadless solder scaling powder of selecting the combination of natural rosin and disproportionated rosin as film forming agent for use, and its weight proportion consists of:
BiCl
3 0.8％
Natural rosin 25%
Disproportionated rosin 20%
FSN 0.8％
BTA 1.5%
Absolute ethyl alcohol 51.9%
Compound method is with embodiment 1.
The use of scaling powder is with embodiment 3.
Claims (5)
1. SnZn series leadless solder scaling powder, comprising: film forming agent, surfactant, corrosion inhibiter and solvent is characterized in that:
A) also comprise activator BiCl
3
B) the weight percent proportioning wt% of each composition is:
Activator: BiCl
30.05～6%;
Film forming agent: rosin 30-60%;
Surfactant: FSN 0.1～1%;
Corrosion inhibiter: BTA 0.01～2%;
All the other are solvent: absolute ethyl alcohol.
2. a kind of SnZn series leadless solder scaling powder according to claim 1 is characterized in that: each composition optimum of scaling powder is: activator BiCl
30.5%, film forming agent rosin 45%, surfactant FSN 0.8%, corrosion inhibiter BTA 1.5%, solvent absolute ethyl alcohol 52.2%.
3. a kind of SnZn series leadless solder scaling powder according to claim 1 is characterized in that: described rosin is one or more combinations in natural rosin or Foral or newtrex or the disproportionated rosin.
4. a kind of SnZn series leadless solder scaling powder according to claim 1, it is characterized in that: surfactant FSN is the nonionic fluorine surfactant.
5. prepare the method for a kind of SnZn series leadless solder as claimed in claim 1 with scaling powder, it is characterized in that the method step of its preparation is: the first step is by the percentage by weight of its each composition, with its BiCl
3, rosin, FSN, the weighing of phenylpropyl alcohol triazole is good, and puts into beaker; Second step added load weighted in proportion solvent absolute ethyl alcohol in the beaker, and sealing makes solid material fully dissolve at normal temperatures; The 3rd step was the scaling powder product after filtering out impurity with the filter of aperture 1.5 μ m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2007100101144A CN100455400C (en) | 2007-01-16 | 2007-01-16 | Soldering flux in use for SnZn series solder with no lead, and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2007100101144A CN100455400C (en) | 2007-01-16 | 2007-01-16 | Soldering flux in use for SnZn series solder with no lead, and preparation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101003111A true CN101003111A (en) | 2007-07-25 |
| CN100455400C CN100455400C (en) | 2009-01-28 |
Family
ID=38702611
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2007100101144A Expired - Fee Related CN100455400C (en) | 2007-01-16 | 2007-01-16 | Soldering flux in use for SnZn series solder with no lead, and preparation method |
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| CN (1) | CN100455400C (en) |
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| CN101829863A (en) * | 2010-05-29 | 2010-09-15 | 中铁二十一局集团有限公司 | Liquid soldering flux for soldering electrical products |
| CN102581522A (en) * | 2012-02-28 | 2012-07-18 | 河南科技大学 | Rosin-based flux for ZnSn-based lead free solder and preparation method thereof |
| CN102785040A (en) * | 2012-08-27 | 2012-11-21 | 罗宁 | Interconnecting bar for solar photovoltaic modules |
| CN103537822A (en) * | 2013-10-25 | 2014-01-29 | 广州汉源新材料有限公司 | High-concentration scaling powder for pre-forming soldering lug spraying |
| CN104526186A (en) * | 2014-12-26 | 2015-04-22 | 苏州龙腾万里化工科技有限公司 | Novel scaling powder for SnZn series lead-free brazing filler metal |
| CN105728984A (en) * | 2014-12-25 | 2016-07-06 | 千住金属工业株式会社 | Flux For Resin Flux Cored Solder, Flux For Flux Coated Solder, Resin Flux Cored Solder And Flux Coated Solder |
| CN106271219A (en) * | 2016-08-26 | 2017-01-04 | 王泽陆 | A kind of No clean high-temperature electronic brazing flux and preparation method thereof |
| CN111531292A (en) * | 2020-05-15 | 2020-08-14 | 湖北省哈福生物化学有限公司 | Tin spraying soldering flux and preparation method thereof |
| CN112270098A (en) * | 2020-11-02 | 2021-01-26 | 桂林电子科技大学 | Steady optimization design method for hot air reflow soldering process |
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| CN1056795C (en) * | 1997-02-21 | 2000-09-27 | 清华大学 | Solid soldering agent used in soldering tin rod |
| JP4017088B2 (en) * | 1997-08-07 | 2007-12-05 | ハリマ化成株式会社 | Solder paste |
| JP3394703B2 (en) * | 1998-03-16 | 2003-04-07 | ハリマ化成株式会社 | Flux for solder |
| JP3788335B2 (en) * | 2001-12-07 | 2006-06-21 | 千住金属工業株式会社 | Solder paste |
| CN1307024C (en) * | 2004-05-09 | 2007-03-28 | 邓和升 | High adhesion leadless soldering tin grease |
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- 2007-01-16 CN CNB2007100101144A patent/CN100455400C/en not_active Expired - Fee Related
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101829863A (en) * | 2010-05-29 | 2010-09-15 | 中铁二十一局集团有限公司 | Liquid soldering flux for soldering electrical products |
| CN101829863B (en) * | 2010-05-29 | 2011-12-21 | 中铁二十一局集团有限公司 | Liquid soldering flux for soldering electrical products |
| CN102581522A (en) * | 2012-02-28 | 2012-07-18 | 河南科技大学 | Rosin-based flux for ZnSn-based lead free solder and preparation method thereof |
| CN102785040A (en) * | 2012-08-27 | 2012-11-21 | 罗宁 | Interconnecting bar for solar photovoltaic modules |
| CN103537822A (en) * | 2013-10-25 | 2014-01-29 | 广州汉源新材料有限公司 | High-concentration scaling powder for pre-forming soldering lug spraying |
| CN105728984A (en) * | 2014-12-25 | 2016-07-06 | 千住金属工业株式会社 | Flux For Resin Flux Cored Solder, Flux For Flux Coated Solder, Resin Flux Cored Solder And Flux Coated Solder |
| US10265808B2 (en) | 2014-12-25 | 2019-04-23 | Senju Metal Industry Co., Ltd. | Flux for resin flux cored solder, flux for flux coated solder, resin flux cored solder and flux coated solder |
| CN105728984B (en) * | 2014-12-25 | 2020-08-11 | 千住金属工业株式会社 | Flux for rosin core soft solder, flux for flux-coated soft solder, rosin core soft solder, and flux-coated soft solder |
| CN104526186A (en) * | 2014-12-26 | 2015-04-22 | 苏州龙腾万里化工科技有限公司 | Novel scaling powder for SnZn series lead-free brazing filler metal |
| CN106271219A (en) * | 2016-08-26 | 2017-01-04 | 王泽陆 | A kind of No clean high-temperature electronic brazing flux and preparation method thereof |
| CN111531292A (en) * | 2020-05-15 | 2020-08-14 | 湖北省哈福生物化学有限公司 | Tin spraying soldering flux and preparation method thereof |
| CN112270098A (en) * | 2020-11-02 | 2021-01-26 | 桂林电子科技大学 | Steady optimization design method for hot air reflow soldering process |
| CN112270098B (en) * | 2020-11-02 | 2022-02-18 | 桂林电子科技大学 | Steady optimization design method for hot air reflow soldering process |
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