JPH02201264A - Quantitative analysis of tin (ii) in tin plating bath - Google Patents
Quantitative analysis of tin (ii) in tin plating bathInfo
- Publication number
- JPH02201264A JPH02201264A JP1974489A JP1974489A JPH02201264A JP H02201264 A JPH02201264 A JP H02201264A JP 1974489 A JP1974489 A JP 1974489A JP 1974489 A JP1974489 A JP 1974489A JP H02201264 A JPH02201264 A JP H02201264A
- Authority
- JP
- Japan
- Prior art keywords
- tin
- plating bath
- copper
- titration
- quantitative analysis
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 title claims abstract description 24
- 238000007747 plating Methods 0.000 title claims abstract description 24
- IUTCEZPPWBHGIX-UHFFFAOYSA-N tin(2+) Chemical compound [Sn+2] IUTCEZPPWBHGIX-UHFFFAOYSA-N 0.000 title claims abstract description 23
- 238000004445 quantitative analysis Methods 0.000 title claims abstract description 8
- 238000004448 titration Methods 0.000 claims abstract description 21
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 claims abstract description 18
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 claims abstract description 17
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical compound [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 claims abstract description 12
- 230000000873 masking effect Effects 0.000 claims abstract description 11
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 claims abstract description 9
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 9
- SYRHIZPPCHMRIT-UHFFFAOYSA-N tin(4+) Chemical compound [Sn+4] SYRHIZPPCHMRIT-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000011975 tartaric acid Substances 0.000 claims abstract description 6
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 claims abstract description 5
- 235000002906 tartaric acid Nutrition 0.000 claims abstract description 5
- 229940095064 tartrate Drugs 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 8
- 229910021645 metal ion Inorganic materials 0.000 abstract description 9
- 230000000694 effects Effects 0.000 abstract description 5
- LJCNRYVRMXRIQR-OLXYHTOASA-L potassium sodium L-tartrate Chemical compound [Na+].[K+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O LJCNRYVRMXRIQR-OLXYHTOASA-L 0.000 abstract description 3
- 239000001476 sodium potassium tartrate Substances 0.000 abstract description 3
- 235000011006 sodium potassium tartrate Nutrition 0.000 abstract description 3
- 239000007788 liquid Substances 0.000 abstract 2
- 239000000243 solution Substances 0.000 description 10
- 238000002474 experimental method Methods 0.000 description 7
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 5
- 229910052802 copper Inorganic materials 0.000 description 5
- 239000010949 copper Substances 0.000 description 5
- DIZZDZCUMBBRSG-UHFFFAOYSA-J tetrasodium;2-[[5-[3-[3-[[bis(carboxylatomethyl)amino]methyl]-4-hydroxy-2-methyl-5-propan-2-ylphenyl]-1,1-dioxo-2,1$l^{6}-benzoxathiol-3-yl]-2-hydroxy-6-methyl-3-propan-2-ylphenyl]methyl-(carboxylatomethyl)amino]acetate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-]C(=O)CN(CC([O-])=O)CC1=C(O)C(C(C)C)=CC(C2(C3=CC=CC=C3S(=O)(=O)O2)C=2C(=C(CN(CC([O-])=O)CC([O-])=O)C(O)=C(C(C)C)C=2)C)=C1C DIZZDZCUMBBRSG-UHFFFAOYSA-J 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- 239000007974 sodium acetate buffer Substances 0.000 description 3
- BHZOKUMUHVTPBX-UHFFFAOYSA-M sodium acetic acid acetate Chemical compound [Na+].CC(O)=O.CC([O-])=O BHZOKUMUHVTPBX-UHFFFAOYSA-M 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 239000000872 buffer Substances 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- YYYMFKRTPPSNJH-UHFFFAOYSA-N [Sn+] Chemical compound [Sn+] YYYMFKRTPPSNJH-UHFFFAOYSA-N 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000013626 chemical specie Substances 0.000 description 1
- 230000000536 complexating effect Effects 0.000 description 1
- 238000010668 complexation reaction Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000007772 electroless plating Methods 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000003446 ligand Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 239000012488 sample solution Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 150000003892 tartrate salts Chemical class 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は錫めっき浴に溶存する錫（ＩＩ）を精度よく分
析する方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for accurately analyzing tin (II) dissolved in a tin plating bath.
近年、電子工業部品製造の分野で無電解錫めっきの利用
が増大しつつある。 その理由はこの方法によると、め
っき皮膜の密着性が良好で、複雑な形状の材料に対して
も均一で平滑な錫めっきができることにある。 無電解
めっき浴は錫（ＩＩ）金属塩、還元剤および緩衝剤を含
んでおり、めっき作業に際しては浴中錫（ＩＩ）の消費
を逐次監視しつつ必要な薬剤を補給する必要がある。
ところで通常新規調製しためっき浴中の錫（ＩＩ）の定
量方法としてはＥＤＴＡ （エチレンジアミン四酢酸）
滴定法が適用されている。 この方法は一定量の試料液
を採取し、緩衝剤とメチルチモールブルー（ＭＴＢ）指
示薬を添加し、ＥＤＴＡで滴定する方法である。 しか
しながら、調製直後のめっき浴であればこの方法でも利
用するのに差し支えないが、操業中のめっき浴の場合に
は錫（ＩＩ）の酸化により錫（ＩＶ）が、さらに銅また
は銅合金に対するめっきでは部材の溶解により銅（ＩＩ
）イオン等が溶出共存しており、これらの妨害のために
ＥＤＴＡ滴定法をそのままでは適用できないという問題
点があった。In recent years, the use of electroless tin plating has been increasing in the field of manufacturing electronic industrial parts. The reason for this is that, according to this method, the adhesion of the plating film is good and uniform and smooth tin plating can be performed even on materials with complicated shapes. The electroless plating bath contains a tin (II) metal salt, a reducing agent, and a buffer agent, and during plating work, it is necessary to continuously monitor the consumption of tin (II) in the bath and replenish the necessary chemicals.
By the way, the usual method for quantifying tin (II) in a newly prepared plating bath is EDTA (ethylenediaminetetraacetic acid).
Titration method is applied. In this method, a certain amount of sample solution is collected, a buffer and a methyl thymol blue (MTB) indicator are added, and the sample is titrated with EDTA. However, if it is a plating bath that has just been prepared, this method can be used, but in the case of a plating bath that is in operation, tin (IV) is produced by oxidation of tin (II), and further plating on copper or copper alloys. In this case, copper (II) is produced by melting the parts.
) ions and the like coexist in elution, and due to these interferences, there was a problem that the EDTA titration method could not be applied as it was.
本発明は適当なマスキング剤を使用することによって、
妨害元素の分離除去等の煩雑な操作を行うことな（、簡
単迅速に現場で実施できる分析方法を提供することを目
的とする。By using a suitable masking agent, the present invention can
The purpose is to provide an analysis method that can be easily and quickly implemented on-site without the need for complicated operations such as separating and removing interfering elements.
上記目的を達成するため本発明の方法はＥＤＴＡ滴定法
で錫めっき浴中の錫（ＩＩ）を定量分析する際に錫（ｒ
Ｖ）に対しては酒石酸および／または酒石酸塩を、銅（
ＩＩ）に対してはチオ尿素をマスキング剤として用いる
ことによって錫めっき浴中錫（ＩＩ）の定量分析を行う
点に特徴がある。In order to achieve the above object, the method of the present invention uses EDTA titration to quantitatively analyze tin (II) in a tin plating bath.
V), tartaric acid and/or tartrate, copper (
Regarding II), a feature is that the quantitative analysis of tin (II) in the tin plating bath is performed by using thiourea as a masking agent.
即ち、本発明の分析方法は錫（ｒＶ）対しては酒石酸お
よび／または酒石酸塩を用い、また銅（ＩＩ）に対して
はチオ尿素を用い、それぞれ錯形成させることにより、
滴定条件においてＥＤＴＡとの配位子置換反応に対して
不活性な化学種と成してマスキングすることによって、
妨害金属イオンを分離除去する煩雑な操作を行うことな
（、そのままＭＴＢを指示薬としてＥＤＴＡ滴定するこ
とにある。 本発明法において酒石酸および／または酒
石酸塩、チオ尿素がマスキング効果を奏する理由は明ら
かではないが、錫（ｒＶ）−酒石酸および銅（ＩＩ）−
チオ尿素錯体の滴定条件での安定度が、錫（ｒＶ）−Ｅ
ＤＴＡおよび銅（ＩＩ）−ＥＤＴＡ錯体の安定度よりも
大きいために、錫（ＩＩ）だけが定量的にＥＤＴＡと反
応することによるものと考えられる。That is, the analytical method of the present invention uses tartaric acid and/or tartrate for tin (rV), and thiourea for copper (II), and by complexing them,
By masking it as an inert chemical species against the ligand displacement reaction with EDTA under titration conditions,
It is not clear why tartaric acid and/or tartrate salts and thiourea have a masking effect in the method of the present invention. No, but tin(rV)-tartaric acid and copper(II)-
The stability of the thiourea complex under titration conditions is
This is believed to be due to the fact that only tin(II) quantitatively reacts with EDTA because the stability is greater than that of DTA and the copper(II)-EDTA complex.
本定量法におけるマスキング剤の添加量とマスキングで
きる金属イオン量との関係を検討したところ、ｌＯｗ／
ｖ％酒石酸ナト酒石酸ナトリウムカリウム溶液１舶
また、５ｗ／ｖ％チオ尿素溶液１０ｍ込の添加で銅（Ｉ
Ｉ）の２００ｍｇまでをそれぞれマスクでき、しかもそ
の添加量では互いの錯形成やＥＤＴＡによる錫（ＩＩ）
の滴定を妨害することはないことが分かった。 なお上
記の金属イオン量（２ ０ ０ｍｇ）は本定量法におけ
るめっき浴液採取量を５ｍ込とするとそれぞれ４ ０
ｇ／Ｑの濃度までの分析時の共存を許容することになり
、本定量法の適用対象の一つであるめっき浴（シトレイ
社製 ティンボジッ） ＬＴ−３４）の錫（ＩＩ）含
有濃度が２９、４ｇ／込であることから、上記量のマス
キング剤を添加すれば充分マスキングし得ることが分か
る。When we investigated the relationship between the amount of masking agent added and the amount of metal ions that can be masked in this quantitative method, we found that lOw/
Copper (I
It is possible to mask up to 200mg of each of I), and at that amount, it is possible to mask mutual complexation and tin(II) due to EDTA.
was found not to interfere with the titration of The amount of metal ions mentioned above (200 mg) is 400 mg, respectively, if the amount of plating bath solution collected in this quantitative method is 5 m.
This allows the coexistence of tin(II) up to a concentration of 29g/Q during analysis, and the tin(II) content of the plating bath (Timbojit LT-34, manufactured by Citray Co., Ltd.), which is one of the targets for this quantitative method, is 29g/Q. , 4 g/inclusive, it can be seen that sufficient masking can be achieved by adding the above amount of masking agent.
本実施例においては、すべて特級試薬あるいはそれに準
拠する試薬を用い、水は蒸留水を用いた。In this example, all special grade reagents or reagents based on them were used, and distilled water was used as water.
先ずマスキング剤の添加効果を確認するために以下の実
験を行った。 即ち実験Ｎｏ．１〜６では錫（■）、錫
（■）および銅（ＩＩ）金属イオンの１ｗ／ｖ％溶液を
それぞれ金属イオン添加量ｆＪ．Ｅ所定の値となるよう
に採取し、１ ０ ｗ／ｖ％酒石酸ナトリウムカリウム
溶液１０ ｍ９， ｊニー ５ｗ／ｖ％チオ尿素溶液１
０ｍ２とを添加して十分に混合し、１Ｍ酢酸−酢酸ナト
リウム緩衝液２、５ ｍｌと水を２０ないし３０ｍ１加
えてｐＨを約５とし、０．１ ％ＭＴＢ指示薬を数滴添
加した後０．０５ Ｍ ＥＤＴＡ溶液を用いて攪拌しな
がら滴定した。 滴定液に錫（Ｉｆ）が含まれていれば
滴定前は青色を呈し終点では黄色へと変７色する。 各
実験Ｎｏ．の金属イオン添加量と滴定値および錫（ＩＩ
）検出量を第１表に示す。 実験Ｎｏ． ｌ， ２テは
錫（ＩＩ） のほぼ１００％が回収されたが、実験Ｎｏ
、３〜６ではＭＴＢ指示薬添加の時点で既に黄色を呈し
ており滴定不能であったが、錫（ｍＶ）や銅（ＩＩ）が
存在しても滴定に正の誤差を与えないことが分かる。First, the following experiment was conducted to confirm the effect of adding a masking agent. That is, experiment no. In Nos. 1 to 6, 1 w/v % solutions of tin (■), tin (■), and copper (II) metal ions were added in amounts of metal ions fJ. E Collect to the specified value, 10 w/v% sodium potassium tartrate solution 10 m9, j 5 w/v% thiourea solution 1
Add 0 ml of 1M acetic acid-sodium acetate buffer and mix thoroughly, add 2.5 ml of 1M acetic acid-sodium acetate buffer and 20 to 30 ml of water to bring the pH to about 5, add a few drops of 0.1% MTB indicator, and then add 0.0 ml of 1M acetic acid-sodium acetate buffer. Titrated with 05M EDTA solution while stirring. If the titrant contains tin (If), it will turn blue before the titration and change to yellow at the end point. Each experiment no. The amount of metal ions added, titration value, and tin (II)
) The detected amounts are shown in Table 1. Experiment No. Almost 100% of tin(II) was recovered in Experiment No. 1 and 2, but in Experiment No.
, 3 to 6 were already yellow at the time of addition of the MTB indicator and titration was impossible, but it can be seen that even the presence of tin (mV) and copper (II) does not cause a positive error in titration.
実験Ｎｏ、７〜１２では操業中のめっき浴液（シトレイ
社製 ティンポジット ＬＴ−３４）をそれぞれ５ｍ込
採取しこれに錫（■）、錫（ＩＶ）および銅（ＩＩ）金
属イオンの１ｗ／ｖ％溶液をそれぞれ金属イオン添加量
が所定の値となるように採取して混合し、さらに酒石酸
ナトリウムカリウム溶液とチオ尿素溶液とを前記と同様
添加混合した。 各混合条件と滴定結果を第１表に示す
。In Experiment Nos. 7 to 12, 5 m of each plating bath solution (Tinposit LT-34 manufactured by Citray) was sampled during operation, and 1 w/w of tin (■), tin (IV) and copper (II) metal ions were collected. v % solution was collected and mixed so that the amount of metal ions added was a predetermined value, and then a sodium potassium tartrate solution and a thiourea solution were added and mixed in the same manner as above. Table 1 shows the mixing conditions and titration results.
ＥＤＴＡ滴定の結果、錫（・■）および銅（ＩＩ）の共
存はともに滴定値にはなんら影響を与えずめっき浴中の
錫（ＩＩ）は約１３０ｍｇであることが分かった。 即
ちこの錫めっき浴に含まれる錫（■）の濃度は２６．０
ｇ／込であることが分かった。 なお錫（ＩＩ）
ｆｆｉはＥＤＴＡの滴定値から次式により計算した。As a result of EDTA titration, it was found that the coexistence of both tin (.■) and copper (II) had no effect on the titration value, and the amount of tin (II) in the plating bath was about 130 mg. That is, the concentration of tin (■) contained in this tin plating bath is 26.0
It turned out that it was g/inclusive. Furthermore, tin (II)
ffi was calculated from the titration value of EDTA using the following formula.
Ｓｎ （ＩＩ） ＝ ５．９３ Ｘ ｆＥＤｌｐ
Ｘ滴定値［ｍｇ］ ［ｍｇ／ｒｌ］ ［−］
［ｍｕ］ここで、ｆＥＤ工、は０．０５ Ｍ
ＥＤＴＡ溶液の力価を表わす。Sn (II) = 5.93 x fEDlp
X titration value [mg] [mg/rl] [-]
[mu] Here, fED engineering is 0.05 M
Represents the titer of the EDTA solution.
本発明によって、操業中の錫めっき浴に含まれる錫（Ｉ
［）のＥＤＴＡ滴定に際し、正の誤差を与える錫（ＩＶ
）及び銅（ＩＩ）が共存しても、きわめて高い精度で錫
（ＩＩ）の定量が可能となり、きめ細かい浴管理に必要
な錫（ＩＩ）濃度に関する情報の入手が簡単迅速にでき
るようになった。According to the present invention, tin (I) contained in the tin plating bath during operation is
In the EDTA titration of [), tin (IV
) and copper (II) coexist, it is now possible to quantify tin (II) with extremely high accuracy, and it has become possible to easily and quickly obtain information on the tin (II) concentration necessary for detailed bath management. .
Claims (1)
に際し、錫（IV）に対しては酒石酸および／または酒石
酸塩を、銅（II）に対してはチオ尿素をマスキング剤と
して用いることを特徴とする錫めっき浴中錫（II）の定
量分析法。When quantitatively analyzing tin (II) in a tin plating bath using the EDTA titration method, use tartaric acid and/or tartrate as a masking agent for tin (IV) and thiourea as a masking agent for copper (II). A quantitative analysis method for tin (II) in a tin plating bath, characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1974489A JPH02201264A (en) | 1989-01-31 | 1989-01-31 | Quantitative analysis of tin (ii) in tin plating bath |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1974489A JPH02201264A (en) | 1989-01-31 | 1989-01-31 | Quantitative analysis of tin (ii) in tin plating bath |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02201264A true JPH02201264A (en) | 1990-08-09 |
Family
ID=12007844
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1974489A Pending JPH02201264A (en) | 1989-01-31 | 1989-01-31 | Quantitative analysis of tin (ii) in tin plating bath |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02201264A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0501480A2 (en) * | 1991-03-01 | 1992-09-02 | C. Uyemura & Co, Ltd | Analysis of tin, lead or tin-lead alloy plating solution |
-
1989
- 1989-01-31 JP JP1974489A patent/JPH02201264A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0501480A2 (en) * | 1991-03-01 | 1992-09-02 | C. Uyemura & Co, Ltd | Analysis of tin, lead or tin-lead alloy plating solution |
| US5294554A (en) * | 1991-03-01 | 1994-03-15 | C. Uyemura & Co., Ltd. | Analysis of tin, lead or tin-lead alloy plating solution |
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