JPH04350172A - Electroless gold plating solution - Google Patents
Electroless gold plating solutionInfo
- Publication number
- JPH04350172A JPH04350172A JP22374591A JP22374591A JPH04350172A JP H04350172 A JPH04350172 A JP H04350172A JP 22374591 A JP22374591 A JP 22374591A JP 22374591 A JP22374591 A JP 22374591A JP H04350172 A JPH04350172 A JP H04350172A
- Authority
- JP
- Japan
- Prior art keywords
- plating solution
- gold plating
- plating
- bath
- electroless gold
- 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
- 238000007747 plating Methods 0.000 title claims abstract description 93
- 239000010931 gold Substances 0.000 title claims abstract description 67
- 229910052737 gold Inorganic materials 0.000 title claims abstract description 67
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 title claims abstract description 64
- 239000000243 solution Substances 0.000 claims abstract description 55
- YXIWHUQXZSMYRE-UHFFFAOYSA-N 1,3-benzothiazole-2-thiol Chemical compound C1=CC=C2SC(S)=NC2=C1 YXIWHUQXZSMYRE-UHFFFAOYSA-N 0.000 claims abstract description 48
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 claims abstract description 20
- 150000003839 salts Chemical class 0.000 claims abstract description 15
- 239000002253 acid Substances 0.000 claims abstract description 10
- 235000010323 ascorbic acid Nutrition 0.000 claims abstract description 10
- 239000011668 ascorbic acid Substances 0.000 claims abstract description 10
- 229960005070 ascorbic acid Drugs 0.000 claims abstract description 10
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical class OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 claims abstract description 8
- DHCDFWKWKRSZHF-UHFFFAOYSA-N sulfurothioic S-acid Chemical class OS(O)(=O)=S DHCDFWKWKRSZHF-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052783 alkali metal Inorganic materials 0.000 claims abstract description 6
- -1 alkali metal salt Chemical class 0.000 claims description 9
- 150000003863 ammonium salts Chemical class 0.000 claims description 5
- 239000006174 pH buffer Substances 0.000 claims description 5
- 239000007864 aqueous solution Substances 0.000 claims description 3
- 239000000470 constituent Substances 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 2
- 239000002244 precipitate Substances 0.000 abstract description 15
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 239000000203 mixture Substances 0.000 abstract description 4
- 239000007788 liquid Substances 0.000 abstract description 3
- 239000007853 buffer solution Substances 0.000 abstract description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 abstract 1
- 150000001340 alkali metals Chemical class 0.000 abstract 1
- 239000012266 salt solution Substances 0.000 abstract 1
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 10
- 230000000694 effects Effects 0.000 description 10
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 6
- 238000000354 decomposition reaction Methods 0.000 description 5
- 229910052759 nickel Inorganic materials 0.000 description 5
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 4
- 235000019345 sodium thiosulphate Nutrition 0.000 description 4
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 150000002343 gold Chemical class 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- 159000000000 sodium salts Chemical class 0.000 description 3
- 235000010265 sodium sulphite Nutrition 0.000 description 3
- PPASLZSBLFJQEF-RXSVEWSESA-M sodium-L-ascorbate Chemical compound [Na+].OC[C@H](O)[C@H]1OC(=O)C(O)=C1[O-] PPASLZSBLFJQEF-RXSVEWSESA-M 0.000 description 3
- SJUCACGNNJFHLB-UHFFFAOYSA-N O=C1N[ClH](=O)NC2=C1NC(=O)N2 Chemical class O=C1N[ClH](=O)NC2=C1NC(=O)N2 SJUCACGNNJFHLB-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000003788 bath preparation Substances 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- BNIILDVGGAEEIG-UHFFFAOYSA-L disodium hydrogen phosphate Chemical compound [Na+].[Na+].OP([O-])([O-])=O BNIILDVGGAEEIG-UHFFFAOYSA-L 0.000 description 2
- 229910021645 metal ion Inorganic materials 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- AJPJDKMHJJGVTQ-UHFFFAOYSA-M sodium dihydrogen phosphate Chemical compound [Na+].OP(O)([O-])=O AJPJDKMHJJGVTQ-UHFFFAOYSA-M 0.000 description 2
- 239000001488 sodium phosphate Substances 0.000 description 2
- 229910000162 sodium phosphate Inorganic materials 0.000 description 2
- 239000011755 sodium-L-ascorbate Substances 0.000 description 2
- 235000019187 sodium-L-ascorbate Nutrition 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 231100000331 toxic Toxicity 0.000 description 2
- 230000002588 toxic effect Effects 0.000 description 2
- RYFMWSXOAZQYPI-UHFFFAOYSA-K trisodium phosphate Chemical compound [Na+].[Na+].[Na+].[O-]P([O-])([O-])=O RYFMWSXOAZQYPI-UHFFFAOYSA-K 0.000 description 2
- 230000010718 Oxidation Activity Effects 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 239000008139 complexing agent Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000007772 electroless plating Methods 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- ZBKIUFWVEIBQRT-UHFFFAOYSA-N gold(1+) Chemical compound [Au+] ZBKIUFWVEIBQRT-UHFFFAOYSA-N 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 150000002825 nitriles Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- PPASLZSBLFJQEF-RKJRWTFHSA-M sodium ascorbate Substances [Na+].OC[C@@H](O)[C@H]1OC(=O)C(O)=C1[O-] PPASLZSBLFJQEF-RKJRWTFHSA-M 0.000 description 1
- 235000010378 sodium ascorbate Nutrition 0.000 description 1
- 229960005055 sodium ascorbate Drugs 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- ZWZLRIBPAZENFK-UHFFFAOYSA-J sodium;gold(3+);disulfite Chemical compound [Na+].[Au+3].[O-]S([O-])=O.[O-]S([O-])=O ZWZLRIBPAZENFK-UHFFFAOYSA-J 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Chemically Coating (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、金源として塩化金酸を
用いた無電解金めっき液に関する。詳しくは、塩化金酸
またはその塩、亜硫酸及びチオ硫酸のアルカリ金属塩ま
たはアンモニウム塩、アスコルビン酸またはその塩及び
ｐＨ緩衝剤を水溶液の組成成分として含有する無電解金
めっき液に２−メルカプトベンゾチアゾールを含有せし
め、長時間連続使用や長期保存安定性に優れた新規な無
電解金めっき液に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroless gold plating solution using chloroauric acid as a gold source. Specifically, 2-mercaptobenzothiazole is added to an electroless gold plating solution containing chloroauric acid or its salt, an alkali metal salt or ammonium salt of sulfite and thiosulfate, ascorbic acid or its salt, and a pH buffer agent as constituents of the aqueous solution. The present invention relates to a new electroless gold plating solution that contains .
【０００２】0002
【背景技術】無電解金めっき法は、その優れた機能特性
から複雑な微細回路やリードのとりにくい孤立した部分
等へのめっきが要求される電子産業分野において幅広く
利用されている。従来の無電解金めっき液は、金（Ｉ）
イオンの錯化剤として毒性の強いシアン化合物を含んで
おり、高温度、強アルカリ条件で使用されているのが通
例であった。そのため前述した用途においては、回路の
マスキングに用いたレジストの剥離、あるいはアルカリ
によりセラミック基板素地の侵蝕等の問題がおこり、ま
た、シアン化合物は、毒性が高く、実作業環境の安全性
、取り扱いや保管及び管理上の問題があり、さらに廃液
処理の経済面の問題もある。BACKGROUND ART Due to its excellent functional properties, electroless gold plating is widely used in the electronic industry, where plating is required on complex microcircuits and isolated parts where leads are difficult to reach. Conventional electroless gold plating solution is gold(I)
It contains a highly toxic cyanide compound as an ion complexing agent, and is typically used at high temperatures and under strong alkaline conditions. Therefore, in the above-mentioned applications, problems such as peeling off of the resist used for masking the circuit and corrosion of the ceramic substrate base due to alkali occur.In addition, cyanide compounds are highly toxic, and there are concerns regarding safety in the actual working environment and handling. There are storage and management issues, as well as economic issues with waste disposal.
【０００３】他方、シアン化合物を用いない無電解金め
っき液としては、代表的なものとして金源に塩化金酸塩
を用いた金めっき液が知られている（例えば、米国特許
４１４２９０２号、英国特許２１１４１５９号参照）こ
の塩化金酸塩を用いた金めっき液は、塩化金酸塩と組成
成分の亜硫酸およびチオ硫酸塩とがそれらの金錯塩を形
成して作用するとされているものでシアン化合物を用い
ない無電解金めっき液として実用化されている。On the other hand, as a typical electroless gold plating solution that does not use a cyanide compound, a gold plating solution that uses chloraurate as a gold source is known (for example, US Pat. No. 4,142,902, British Pat. (See Japanese Patent No. 2114159) This gold plating solution using chlorauric acid salt is said to act by forming a gold complex between chloroauric acid salt and the constituent components sulfite and thiosulfate, and is a cyanide compound. It has been put into practical use as an electroless gold plating solution that does not use
【０００４】本発明者らは、先に、上記塩化金酸を金源
とする無電解金めっき液の改良として、還元成分にアス
コルビン酸を用いた金めっき液を提供した（特開平１−
１９１７８２号公報参照）。かかる無電解金めっき液は
、塩化金酸またはその塩、亜硫酸及びチオ硫酸のアルカ
リ金属塩またはアンモニウム塩、アスコルビン酸または
その塩を組成成分とするもので、低温度ならびに中性付
近の条件で実用的なめっき速度が得られ、さらにセラミ
ック基板を侵すことがなく、マスキングしたレジストを
剥離することもないプリント基板等の微細な回路やリー
ドの金めっき液として適するものである。The present inventors have previously provided a gold plating solution using ascorbic acid as a reducing component as an improvement of the electroless gold plating solution using chloroauric acid as the gold source (Japanese Patent Application Laid-Open No. 1999-1-1912).
(See Publication No. 191782). This electroless gold plating solution contains chloroauric acid or its salts, alkali metal salts or ammonium salts of sulfurous acid and thiosulfuric acid, and ascorbic acid or its salts, and is suitable for practical use at low temperatures and near neutral conditions. It is suitable as a gold plating solution for fine circuits and leads of printed circuit boards, etc., as it can achieve a plating speed of 100%, does not attack ceramic substrates, and does not peel off masked resist.
【０００５】しかしながら、かかる無電解金めっき液も
使用中に微量の沈澱を生成したり、建浴後保存中に金微
粒子の沈澱を生ずるなど、安定性の面で十分とは言えな
いものであった。この場合に、塩化金酸塩と亜硫酸、チ
オ硫酸塩から内部的に金錯体を形成せしめ、アスコルビ
ン酸またはその塩を還元剤とする金めっき浴の安定性が
損われる原因については、理論的には明らかでないが、
以下のようなことが考えられる。[0005] However, such an electroless gold plating solution also produced a small amount of precipitate during use, and fine gold particles precipitated during storage after preparation of the bath, so it could not be said to be sufficient in terms of stability. . In this case, the reason why a gold complex is internally formed from chlorauric acid salt, sulfite, and thiosulfate, and the stability of the gold plating bath using ascorbic acid or its salt as a reducing agent is impaired, is theoretically explained. Although it is not clear,
The following may be considered.
【０００６】保存中あるいはめっき時の亜硫酸イオン、
チオ硫酸イオン等の酸化性成分の自然酸化、濃度減少に
より溶液内平衡が変化し金錯体の不安定化、金活量が増
加し浴分解しやすくなること、またアスコルビン酸の酸
化活性を高める微量金属イオン汚染により、これらを核
とした金微粒子の生成反応等が起こり分解を促進するこ
とになることなどである。[0006] Sulfite ions during storage or plating,
Natural oxidation of oxidizing components such as thiosulfate ions, concentration reduction changes the equilibrium in the solution and destabilizes the gold complex, increases gold activity and makes it easier to decompose in the bath, and trace amounts that increase the oxidation activity of ascorbic acid. Metal ion contamination causes a reaction to generate fine gold particles with these metal ions as the nucleus, which promotes decomposition.
【０００７】[0007]
【発明の開示】本発明者らは、無電解金めっき液の安定
性の向上を目的として鋭意研究を行った結果、塩化金酸
またはその塩、亜硫酸及びチオ硫酸のアルカリ金属塩ま
たはアンモニウム塩、アスコルビン酸またはその塩及び
ｐＨ緩衝剤を水溶液の組成成分として含有する無電解金
めっき液に対し、２−メルカプトベンゾチアゾールを含
有せしめることにより、めっき液の保存時及びめっき実
施時の安定性が著しく向上し、長期使用ならびに長期保
存性がさらに改善されることを見いだした。本発明は、
かかる知見に基づくものである。DISCLOSURE OF THE INVENTION As a result of intensive research aimed at improving the stability of electroless gold plating solutions, the present inventors found that chloroauric acid or its salts, alkali metal salts or ammonium salts of sulfurous acid and thiosulfuric acid, By adding 2-mercaptobenzothiazole to an electroless gold plating solution containing ascorbic acid or its salt and a pH buffer as an aqueous solution component, the stability of the plating solution during storage and during plating is significantly improved. It has been found that long-term use and long-term storage properties are further improved. The present invention
This is based on this knowledge.
【０００８】本発明は、塩化金酸またはその塩、亜硫酸
及びチオ硫酸のアルカリ金属塩またはアンモニウム塩、
アスコルビン酸またはその塩、ｐＨ緩衝剤及び２−メル
カプトベンゾチアゾールまたはその塩を含有する無電解
金めっき液を提供するものである。The present invention provides chloroauric acid or its salts, alkali metal salts or ammonium salts of sulfurous acid and thiosulfuric acid,
An electroless gold plating solution containing ascorbic acid or a salt thereof, a pH buffer, and 2-mercaptobenzothiazole or a salt thereof is provided.
【０００９】以下に、本発明を詳細に説明する。本発明
にかかる無電解金めっき液の好ましい態様は塩化金酸ナ
トリウム０．００１〜０．１０ｍｏｌ／ｌ、亜硫酸ナト
リウム０．０５〜１．０ｍｏｌ／ｌ、チオ硫酸ナトリウ
ム０．０５〜２．０ｍｏｌ／ｌ、りん酸ナトリウム０．
０１〜１．０ｍｏｌ／ｌ、アスコルビン酸まはそのナト
リウム塩として０．００１〜１．００ｍｏｌ／ｌ及び２
−メルカプトベンゾチアゾールまたはそのナトリウム塩
として６×１０−７〜３×１０−５ｍｏｌ／ｌを含有す
るものである。The present invention will be explained in detail below. Preferred embodiments of the electroless gold plating solution according to the present invention include sodium chloraurate 0.001 to 0.10 mol/l, sodium sulfite 0.05 to 1.0 mol/l, and sodium thiosulfate 0.05 to 2.0 mol/l. l, sodium phosphate 0.
01-1.0 mol/l, ascorbic acid or its sodium salt 0.001-1.00 mol/l and 2
- Contains 6 x 10-7 to 3 x 10-5 mol/l of mercaptobenzothiazole or its sodium salt.
【００１０】本発明者らは、本発明にかかる無電解金め
っき液組成に関し、めっき速度とめっき液の安定性につ
いて種々検討したところ、以下の如き知見を得た。The present inventors conducted various studies regarding the plating speed and stability of the electroless gold plating solution according to the present invention, and obtained the following knowledge.
【００１１】（１） 金源として用いられる塩化金酸
またはそのナトリウム塩の使用量については、０．００
１〜０．１０ｍｏｌ／ｌが好ましいが、特に好ましくは
０．００５〜０．０５ｍｏｌ／ｌである。０．００１ｍ
ｏｌ／ｌ以下では実用的なめっき速度は得られずまた、
０．１０ｍｏｌ／ｌ以上ではさらなる顕著な効果が見ら
れず、経済的に不利である。(1) The amount of chloroauric acid or its sodium salt used as a gold source is 0.00
It is preferably 1 to 0.10 mol/l, particularly preferably 0.005 to 0.05 mol/l. 0.001m
Below ol/l, a practical plating rate cannot be obtained, and
If the amount is 0.10 mol/l or more, no further significant effect is observed, which is economically disadvantageous.
【００１２】（２） 亜硫酸ナトリウムについては、
０．０５〜１．０ｍｏｌ／ｌが好ましいが、特に好まし
くは０．１〜０．５ｍｏｌ／ｌである。０．０５ｍｏｌ
／ｌ以下でもまた、１．０ｍｏｌ／ｌ以上でもめっき液
が分解するので、望ましいめっき状態が得られない。(2) Regarding sodium sulfite,
It is preferably 0.05 to 1.0 mol/l, particularly preferably 0.1 to 0.5 mol/l. 0.05mol
If the amount is less than 1.0 mol/l or more than 1.0 mol/l, the plating solution will decompose, making it impossible to obtain a desired plating state.
【００１３】（３） チオ硫酸ナトリウムについては
、０．０５〜２．０ｍｏｌ／ｌが好ましいが、特に好ま
しくは、０．１〜１．０ｍｏｌ／ｌである。０．０５ｍ
ｏｌ／ｌ以下ではめっき液の安定性を欠き分解を生じ易
い。また、２．０ｍｏｌ／ｌ以上ではめっき反応に特別
の効果がない。(3) Sodium thiosulfate is preferably 0.05 to 2.0 mol/l, particularly preferably 0.1 to 1.0 mol/l. 0.05m
If it is less than ol/l, the plating solution lacks stability and is likely to be decomposed. Moreover, if it is 2.0 mol/l or more, there is no special effect on the plating reaction.
【００１４】（４） ｐＨ緩衝剤としては、りん酸ナ
トリウムにより調製された緩衝液が好適であり、その含
有量は、０．０１〜１．０ｍｏｌ／ｌが好ましいが、特
に好ましくは０．０５〜０．５ｍｏｌ／ｌである。０．
０１ｍｏｌ／ｌ以下ではめっき面の粗雑化が生じ易い。
また、１．０ｍｏｌ／ｌ以上ではより以上の効果が期待
できない。(4) As the pH buffer, a buffer solution prepared with sodium phosphate is suitable, and its content is preferably 0.01 to 1.0 mol/l, particularly preferably 0.05 mol/l. ~0.5 mol/l. 0.
If it is less than 0.01 mol/l, the plated surface tends to become rough. Further, if the amount is 1.0 mol/l or more, no further effect can be expected.
【００１５】（５） アスコルビン酸ナトリウムにつ
いては、０．００１〜１．０ｍｏｌ／ｌが好ましいが、
特に好ましくは０．０１〜０．５ｍｏｌ／ｌである。０
．００１ｍｏｌ／ｌ以下ではめっき速度が遅く、また、
１．０ｍｏｌ／ｌ以上ではめっき液が不安定となり、分
解を生じ易くなる。(5) Regarding sodium ascorbate, 0.001 to 1.0 mol/l is preferable, but
Particularly preferably 0.01 to 0.5 mol/l. 0
．． If it is less than 0.001 mol/l, the plating speed is slow, and
If it exceeds 1.0 mol/l, the plating solution becomes unstable and tends to decompose.
【００１６】（６） ２−メルカプトベンゾチアゾー
ルについては、６×１０−７〜３×１０−５ｍｏｌ／ｌ
が好ましいが、特に好ましくは、３×１０−６〜１．５
×１０−５ｍｏｌ／ｌである。６×１０−７ｍｏｌ／ｌ
以下ではめっき液が不安定となり、分解を生じ易いので
好ましくない。また、３×１０−５ｍｏｌ／ｌ以上では
めっき液の安定性は増大するが、めっき速度が遅くなり
好ましくない。(6) For 2-mercaptobenzothiazole, 6×10-7 to 3×10-5 mol/l
is preferred, particularly preferably 3 x 10-6 to 1.5
x10-5 mol/l. 6×10-7 mol/l
Below this, the plating solution becomes unstable and tends to decompose, which is not preferable. Moreover, if it is more than 3×10 −5 mol/l, the stability of the plating solution increases, but the plating speed becomes slow, which is not preferable.
【００１７】（７） 使用時においてめっき液のｐＨ
は、めっき液の成分が分解しない範囲内において硫酸ま
たはカセイソーダ液により適宜調整する。好ましいｐＨ
域は５〜８、特にｐＨ６〜７の範囲とするのが好ましい
。(7) pH of plating solution during use
is appropriately adjusted with sulfuric acid or caustic soda solution within a range that does not decompose the components of the plating solution. preferred pH
The pH range is preferably from 5 to 8, particularly from 6 to 7.
【００１８】（８） めっき液の操作温度は５０〜８
０℃の範囲で適宜選択できるが、好ましくは５０〜７０
℃、さらに好ましくは５５〜６５℃である。このような
低温度においてめっき可能であることは、非めっき対象
物が温度に抵抗を有しない物体の場合、特に好都合であ
り、このことは、さらにエネルギーの節約、作業者の安
全性の点からも従来の無電解金めっき液にない大きな特
徴となる。(8) The operating temperature of the plating solution is 50-8
It can be selected as appropriate within the range of 0°C, but preferably 50 to 70°C.
℃, more preferably 55 to 65℃. The ability to plate at such low temperatures is particularly advantageous when the non-plated object has no resistance to temperature, which further improves energy savings and worker safety. This is a major feature not found in conventional electroless gold plating solutions.
【００１９】次に、本発明の実施例を掲げ、本発明を具
体的に説明する。
実施例１
下記組成の無電解金めっき液（Ａ）を用い、これに各種
濃度で２−メルカプトベンゾチアゾールを含有せしめた
各液を、室温で保存した場合の各液の安定性を調べた。
その結果を後掲表１に示した。Next, the present invention will be specifically explained with reference to examples. Example 1 Using an electroless gold plating solution (A) having the following composition, each solution containing 2-mercaptobenzothiazole at various concentrations was examined for stability when stored at room temperature. The results are shown in Table 1 below.
【００２０】
無電解金めっき液（Ａ）
塩化金酸ナトリウム
金として ２ｇ／Ｌ 亜
硫酸ナトリウム
１０ｇ／Ｌ チオ
硫酸ナトリウム
２０ｇ／Ｌ Ｌ−アス
コルビン酸ナトリウム
４０ｇ／Ｌ りん酸水素二ナトリウム
９ｇ／Ｌ りん酸二水素一ナトリウム
３ｇ／
Ｌ ｐＨ
７．０Electroless gold plating solution (A) Sodium chloroaurate
As gold 2g/L Sodium sulfite
10g/L Sodium thiosulfate
20g/L Sodium L-ascorbate
40g/L Disodium hydrogen phosphate
9g/L monosodium dihydrogen phosphate
3g/
L pH
7.0
【００２１】表１において見られるように
、２−メルカプトベンゾチアゾールを含有していない浴
（比較例１）では、建浴後２日目には既に金の沈澱物を
生成し、不安定で長時間使用及び建浴後数日間保存する
ことも困難であった。As can be seen in Table 1, in the bath not containing 2-mercaptobenzothiazole (Comparative Example 1), gold precipitates were already formed on the second day after bath construction, and the bath was unstable and remained stable for a long time. It was also difficult to store the bath for several days after use and preparation.
【００２２】これに対し、２−メルカプトベンゾチアゾ
ール０．１、０．５、１．０各ｐｐｍ添加浴（実施例）
では、０．１ｐｐｍ添加浴でも６日間、０．５、１．０
各ｐｐｍの添加浴では３０日間、金の沈澱物を生成せず
、無添加の場合に比較して安定性は大幅に改善され、長
期間室温で保存が可能であった。また、５．０ｐｐｍ添
加液では、更に安定性が向上し、２−メルカプトベンゾ
チアゾールの添加濃度が高いほど安定性が良くなる傾向
にあることも判った。これらの実施例からみて本発明に
係る無電解金めっき液が、浴の安定性向上に著しい効果
を有するものであることが認められる。On the other hand, 2-mercaptobenzothiazole 0.1, 0.5, 1.0 ppm addition bath (Example)
So, even in a 0.1 ppm addition bath, 0.5, 1.0
In the bath with each ppm addition, no gold precipitate was formed for 30 days, the stability was significantly improved compared to the case without addition, and it was possible to store at room temperature for a long period of time. It was also found that with a 5.0 ppm additive solution, the stability was further improved, and that the higher the concentration of 2-mercaptobenzothiazole added, the better the stability tended to be. From these Examples, it is recognized that the electroless gold plating solution according to the present invention has a remarkable effect on improving bath stability.
【００２３】実施例２
実施例１と同様の無電解金めっき組成液（Ａ）を調製し
、これに各種濃度で２−メルカプトベンゾチアゾールを
含有せしめた各液を用い、めっき試片として、大きさ２
ｃｍ×２ｃｍ、厚さ０．１ｍｍの圧延ニッケル板に厚さ
３μｍのニッケル皮膜を、次に厚さ３μｍの金皮膜をそ
れぞれ電気めっきしたものを用い、浴負荷０．８ｄｍ２
／Ｌ、温度６０℃、撹拌条件で６時間めっきを行なった
。その結果を後掲表２に示した。Example 2 An electroless gold plating composition solution (A) similar to that in Example 1 was prepared, and each solution containing 2-mercaptobenzothiazole at various concentrations was used to prepare a large plated specimen. Sa2
A rolled nickel plate measuring cm x 2 cm and 0.1 mm thick was electroplated with a 3 μm thick nickel film and then a 3 μm thick gold film, and the bath load was 0.8 dm2.
/L, temperature of 60°C, and stirring conditions for 6 hours. The results are shown in Table 2 below.
【００２４】表２において見られるように、２−メルカ
プトベンゾチアゾールを含有していない浴（比較例）で
は、約３時間で浴中微量金沈澱物の生成がはじまり、６
時間以上使用することは困難であった。As can be seen in Table 2, in the bath containing no 2-mercaptobenzothiazole (comparative example), a trace amount of gold precipitate began to form in the bath in about 3 hours, and after 6 hours.
It was difficult to use it for more than an hour.
【００２５】これに対し、２−メルカプトベンゾチアゾ
ール添加浴（実施例）では、６時間めっき中に金沈澱物
の生成は全く認められず、浴の安定性が向上した。また
金の析出速度については、添加量１ｐｐｍ以下のもので
は無添加の場合と同様のめっき速度であった。なお、添
加量２．５ｐｐｍ以上のものでは僅かにめっき速度が低
下する傾向が認められた。更に、添加量５ｐｐｍのもの
では約３時間でめっきが停止した（浴分解や金の沈澱物
の生成は全く認められていない）。On the other hand, in the 2-mercaptobenzothiazole addition bath (Example), no gold precipitate was observed during the 6-hour plating, and the stability of the bath was improved. Regarding the deposition rate of gold, when the amount added was 1 ppm or less, the plating rate was the same as when no gold was added. It was observed that when the amount added was 2.5 ppm or more, the plating rate tended to decrease slightly. Furthermore, when the addition amount was 5 ppm, plating stopped in about 3 hours (no bath decomposition or formation of gold precipitates was observed at all).
【００２６】これらの実施例からみて本発明に係る無電
解めっき液は適切な添加濃度では析出速度を低下させる
ことなく、浴の安定性向上に著しい効果を有するもので
あることが認められる。From these examples, it is recognized that the electroless plating solution according to the present invention has a remarkable effect on improving the stability of the bath without reducing the deposition rate when added at an appropriate concentration.
【００２７】実施例３
下記組成の無電解金めっき液（Ｂ）及びこの金めっき液
（Ｂ）に２−メルカプトベンゾチアゾール１ｐｐｍを含
有せしめた金めっき浴を調製し、実施例２と同様のめっ
き試片とめっき条件で６時間めっきを行い、室温で一晩
放置後、翌日も、すべて同一条件でめっきを行うという
同じ繰り返し操作を３日間行った。Example 3 An electroless gold plating solution (B) having the following composition and a gold plating bath containing 1 ppm of 2-mercaptobenzothiazole in this gold plating solution (B) were prepared, and the same plating as in Example 2 was carried out. Plating was carried out for 6 hours under the test piece and plating conditions, and after being left at room temperature overnight, plating was carried out the next day under the same conditions, and the same repeated operation was performed for 3 days.
【００２８】
無電解金めっき液（Ｂ）
塩化金酸ナトリウム
金として ２．５ｇ／Ｌ
亜硫酸ナトリウム
１１ｇ／Ｌ
チオ硫酸ナトリウム
２１ｇ／Ｌ
Ｌ−アスコルビン酸ナトリウム
４０ｇ／Ｌ りん酸
水素二ナトリウム
１０ｇ／Ｌ りん酸二水
素一ナトリウム
３ｇ／Ｌ ｐＨ
７．０Electroless gold plating solution (B) Sodium chloroaurate
2.5g/L as gold
sodium sulfite
11g/L
sodium thiosulfate
21g/L
Sodium L-ascorbate
40g/L Disodium hydrogen phosphate
10g/L monosodium dihydrogen phosphate
3g/L pH
7.0
【００２９】
その結果、２−メルカプトベンゾチアゾール無添加浴の
場合には１日目における６時間の平均めっき速度１．０
μｍ／ｈｒでめっき可能であったが、第１日目の約３時
間のめっき時点で、めっき液中に金微粒子の沈澱物が生
成し、更に、一晩の室温放置中に金沈澱物が徐々に増加
し、翌日には多量の沈澱物生成が認められた。そのため
第２日目以降においてはめっきすることが出来なかった
。これに対し、２−メルカプトベンゾチアゾール１ｐｐ
ｍ添加浴では、３日間のめっき期間中金の沈澱物等の浴
中分解物が全く認められず、毎日の繰り返し作業にとも
ない一日約１０％程度の速度の低下は認められたが安定
に３日間めっき可能であった。６時間の平均めっき速度
は、１日目、１．０μｍ／ｈｒ、２日目、０．９１μｍ
／ｈｒ、３日目、０．８０μｍ／ｈｒであった。このよ
うに、２−メルカプトベンゾチアゾールを含有せしめる
ことにより、めっき時の浴安定性の向上のみならず、一
度加熱した液の保存状態での分解防止にも著しい効果が
認められ、長時間繰り返し使用が可能であることが認め
られた。[0029]
As a result, in the case of a 2-mercaptobenzothiazole additive-free bath, the average plating rate for 6 hours on the first day was 1.0
Plating was possible at μm/hr, but after about 3 hours of plating on the first day, a precipitate of gold fine particles was formed in the plating solution, and furthermore, the gold precipitate was left overnight at room temperature. It gradually increased, and a large amount of precipitate was observed to be formed on the next day. Therefore, plating could not be performed after the second day. In contrast, 1 pp of 2-mercaptobenzothiazole
In the m-added bath, no decomposition products such as gold precipitates were observed during the 3-day plating period, and although a decrease in speed of about 10% per day was observed due to repeated work every day, the plating rate remained stable. Plating was possible for 3 days. The average plating rate for 6 hours was 1.0 μm/hr on the 1st day, 0.91 μm on the 2nd day.
/hr, and on the third day, it was 0.80 μm/hr. In this way, the inclusion of 2-mercaptobenzothiazole not only improves bath stability during plating, but also has a remarkable effect on preventing decomposition of the once-heated solution during storage, making it suitable for repeated use over long periods of time. It was recognized that this is possible.
【００３０】実施例４
実施例１で示した無電解金めっき液（Ａ）及びこの金め
っき液（Ａ）に２−メルカプトベンゾチアゾール１ｐｐ
ｍを含有せしめためっき浴を調製し、これらのめっき浴
につき、未使用状態で室温で、表３に示した各保存期間
に保存した。Example 4 The electroless gold plating solution (A) shown in Example 1 and 1 pp of 2-mercaptobenzothiazole were added to this gold plating solution (A).
Plating baths containing m were prepared, and these plating baths were stored unused at room temperature for each storage period shown in Table 3.
【００３１】これら各保存期間のめっき液の一部を用い
て、大きさ２ｃｍ×２ｃｍ、厚さ０．１ｍｍの圧延ニッ
ケル板に厚さ３μｍのニッケル皮膜を、次に厚さ３μｍ
の金皮膜をそれぞれ電気めっきによりつけた物を試片と
して、浴負荷０．８ｄｍ２／Ｌ、温度６０℃、撹拌条件
でめっきを行い各保存期間に保存された各めっき液につ
いて、そのめっき速度ならびに仕上りの外観を比較した
。その結果を後掲表３に示した。[0031] Using a portion of the plating solution from each storage period, a nickel film with a thickness of 3 μm was applied to a rolled nickel plate with a size of 2 cm x 2 cm and a thickness of 0.1 mm, and then a nickel film with a thickness of 3 μm was applied.
Samples were electroplated with a gold film of The finished appearance was compared. The results are shown in Table 3 below.
【００３２】表３に見られるように、２−メルカプトベ
ンゾチアゾールを添加しない浴（比較例）では保存期間
１週間で既に、浴中多量の金沈澱物が生成し、めっきす
ることができなかった。これに対し２−メルカプトベン
ゾチアゾール１ｐｐｍ添加浴（実施例）では２８日まで
液中沈澱物生成等の変化は認められなかった。これらの
保存浴によるめっきでは、１４日保存浴では建浴直後と
同等のめっき速度でめっきが可能であり、最大２８日保
存浴までめっきが可能であった。３５日保存浴では金沈
澱が生成し、めっき不能であった。なお、保存１４日以
上になるとめっき浴が僅かに黄色に着色しはじめ、保存
期間が長くなるにつれて着色が濃くなる傾向にあった。As seen in Table 3, in the bath without 2-mercaptobenzothiazole (comparative example), a large amount of gold precipitate was already formed in the bath after one week of storage, making it impossible to perform plating. . On the other hand, in the bath containing 1 ppm of 2-mercaptobenzothiazole (Example), no changes such as formation of a precipitate in the liquid were observed up to 28 days. In plating using these storage baths, plating was possible in the 14-day storage bath at the same plating speed as immediately after bath preparation, and plating was possible up to 28 days in the storage bath. In the 35-day storage bath, a gold precipitate was formed and plating was impossible. It should be noted that the plating bath began to be slightly colored yellow after storage for 14 days or more, and the coloring tended to become darker as the storage period became longer.
【００３３】また、２−メルカプトベンゾチアゾール１
ｐｐｍ添加浴のめっき状態は、めっき浴の保存期間に関
係なく、明黄色無光沢または半光沢の均一な析出膜が得
られた。Furthermore, 2-mercaptobenzothiazole 1
Regarding the plating state of the ppm-added bath, a bright yellow matte or semi-glossy uniform deposited film was obtained regardless of the storage period of the plating bath.
【００３４】このように、２−メルカプトベンゾチアゾ
ールは、めっき液の分解防止に著しい効果を示し、その
結果、使用可能期間が延長され、浴活性を低下させるこ
となく室温での長期間の保存が可能となった。[0034] As described above, 2-mercaptobenzothiazole has a remarkable effect on preventing the decomposition of the plating solution, and as a result, the usable period is extended and long-term storage at room temperature is possible without reducing the bath activity. It has become possible.
【００３５】[0035]
【発明の効果】以上、詳細に説明したように、本発明に
かかる無電解金めっき液は、建浴後の保存状態及び使用
状態において、浴中の沈澱物生成を防止し、安定に長期
間使用でき、また、繰り返し使用が可能で、従来の金め
っき浴のように建浴後直ちに使用しなければならないと
いう作業時間についての制約が解消されるという優れた
利点を有する。したがって、本発明の無電解金めっき液
により、金めっきの経済性ならびに作業性が大幅に改善
される。Effects of the Invention As explained above in detail, the electroless gold plating solution according to the present invention prevents the formation of precipitates in the bath during storage and use after bath preparation, and can be used stably for a long period of time. Moreover, it has the excellent advantage that it can be used repeatedly and eliminates the restriction on working time that the bath must be used immediately after it is prepared, unlike conventional gold plating baths. Therefore, the electroless gold plating solution of the present invention significantly improves the economic efficiency and workability of gold plating.
【００３６】[0036]
【表１】[Table 1]
【００３７】[0037]
【表２】[Table 2]
【００３８】[0038]
【表３】[Table 3]
Claims (1)
オ硫酸のアルカリ金属塩またはアンモニウム塩、アスコ
ルビン酸またはその塩及びｐＨ緩衝剤を水溶液の組成成
分として含有する無電解金めっき液において、２−メル
カプトベンゾチアゾールを含有せしめることを特徴とす
る無電解金めっき液。Claim 1. An electroless gold plating solution containing chloroauric acid or its salt, an alkali metal salt or ammonium salt of sulfite and thiosulfate, ascorbic acid or its salt, and a pH buffer agent as constituents of the aqueous solution, comprising: 2- An electroless gold plating solution characterized by containing mercaptobenzothiazole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22374591A JPH04350172A (en) | 1991-05-28 | 1991-05-28 | Electroless gold plating solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22374591A JPH04350172A (en) | 1991-05-28 | 1991-05-28 | Electroless gold plating solution |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04350172A true JPH04350172A (en) | 1992-12-04 |
Family
ID=16803039
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22374591A Pending JPH04350172A (en) | 1991-05-28 | 1991-05-28 | Electroless gold plating solution |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04350172A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1994012686A1 (en) * | 1992-11-25 | 1994-06-09 | Kanto Kagaku Kabushiki Kaisha | Electroless gold plating bath |
| WO2010104116A1 (en) * | 2009-03-10 | 2010-09-16 | 関東化学株式会社 | Electroless gold plating solution for forming fine gold structure, method of forming fine gold structure using same, and fine gold structure formed using same |
| JP2016098195A (en) * | 2014-11-20 | 2016-05-30 | 小島化学薬品株式会社 | New method for producing non-cyanide gold compound |
-
1991
- 1991-05-28 JP JP22374591A patent/JPH04350172A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1994012686A1 (en) * | 1992-11-25 | 1994-06-09 | Kanto Kagaku Kabushiki Kaisha | Electroless gold plating bath |
| US5470381A (en) * | 1992-11-25 | 1995-11-28 | Kanto Kagaku Kabushiki Kaisha | Electroless gold plating solution |
| WO2010104116A1 (en) * | 2009-03-10 | 2010-09-16 | 関東化学株式会社 | Electroless gold plating solution for forming fine gold structure, method of forming fine gold structure using same, and fine gold structure formed using same |
| JP2010209415A (en) * | 2009-03-10 | 2010-09-24 | Kanto Chem Co Inc | Electroless gold-plating liquid for forming gold micro structure and method for forming gold micro structure using the same, and gold micro structure using the same |
| KR20120005451A (en) * | 2009-03-10 | 2012-01-16 | 간토 가가꾸 가부시키가이샤 | Electroless gold plating solution for forming fine gold structure, method of forming fine gold structure using same, and fine gold structure formed using same |
| US9345145B2 (en) | 2009-03-10 | 2016-05-17 | Kanto Kagaku Kabushiki Kaisha | Electroless gold plating solution for forming fine gold structure, method of forming fine gold structure using same, and fine gold structure formed using same |
| JP2016098195A (en) * | 2014-11-20 | 2016-05-30 | 小島化学薬品株式会社 | New method for producing non-cyanide gold compound |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5470381A (en) | Electroless gold plating solution | |
| Ali et al. | A review of electroless gold deposition processes | |
| US5318621A (en) | Plating rate improvement for electroless silver and gold plating | |
| US5322553A (en) | Electroless silver plating composition | |
| US3032436A (en) | Method and composition for plating by chemical reduction | |
| US5232492A (en) | Electroless gold plating composition | |
| KR20040050887A (en) | Electroless Gold Plating Solution | |
| JPS5925965A (en) | Non-electrolytic copper deposition having rapid plating speed | |
| EP1306466B1 (en) | Electroless gold plating composition | |
| US5391402A (en) | Immersion plating of tin-bismuth solder | |
| JPS60187695A (en) | Silver plating solution and method | |
| EP1026285A2 (en) | Electroless gold plating solution and process | |
| CA2423066A1 (en) | Method for enhancing the solderability of a surface | |
| KR930006123B1 (en) | Electroless gold plating bath and method of using the same | |
| CA1244373A (en) | Gold sulphite electroplating solutions | |
| US3661596A (en) | Stabilized, chemical nickel plating bath | |
| CH655132A5 (en) | AQUEOUS BATH FOR ELECTRIC GOLD PLATING. | |
| JP3148428B2 (en) | Electroless gold plating solution | |
| EP1319734A1 (en) | Plating method | |
| JPH04350172A (en) | Electroless gold plating solution | |
| US5194139A (en) | Pretreating solution for silver plating and silver plating treating process using the solution | |
| US5320667A (en) | Combination of aqueous baths for electroless gold deposition | |
| KR100404369B1 (en) | Electroless Nickel Plating Solution and Method | |
| JP3148427B2 (en) | Electroless gold plating solution | |
| EP0384679B1 (en) | Electrolytic deposition of gold-containing alloys |