DE1621634A1 - Nickel removal bath - Google Patents

Description

Dr. F. Zumsteln son. - Dr. E. Αββηηβηη Dr. R. Koenlgeberger - DipL-Phye. R. Holzbauer - Dr. F. Zumsteln Jun.

PATENT LAWYERS. TKLEFONi 6 AMMEL-NN. M M 41.

| · Ο · Τ · ΟΗΕΟΚΚΟΝΤΟι MONOMS »11 ··

BANK ACCOUNT I BANKHAU H. AUFHXLWEft

° New vontlündlfl · AnmeMunctunteriagew

3100/66

Sooieto PERNIX ENTHONE, Paris, France Entnickelunßöbad

The invention relates to new and venerated Bhtniokun ^ euusam » wetting and a method of using such Composition for removing hiokal tob beams made of steel, Copper, brass and metals or similar alloys. |

The Importance of Improved Unlocking Uncategorized lies mainly in the selectivity of this susceptibility in BeBUg on Niokel, as well as in that no attack on the Carrier metals are made from which the olekoi is replaced '. «Earthen ■ oll.

Trots the application of the most modern working methods of electroplating, like for example the use of an automatic

System, with the most modern metallization solutions and the best add-on technology, a certain proportion of the metallized pieces after the formation of the coating turns out to be defective done exudation of various pickling ~ and Galvanoplastiklösungen from Terunreinigungen the Galvanoplastiklösung (or electrolyte) and originating from other analogous causes "Does the bad metallized Vferkstttck sufficient Fourth, it is economically desirable ₉ all or part of the defective to detach the metallic coating and again form such a coating on the Y / er · = piece au «,.

The metal to be removed must be oxidized from the metallic state in which it is initially, so that it is converted into a certain corresponding ionic state. The active component of the demetallizing solution must therefore be an oxidizing agent _e that the workpiece to be demetallized is held as an anode in the demetallizing vessel, at £ «, <3S the thermoset electrical current exerts the effect of the required oxidizing agent. In one pail as in the other, the demetallizing solution must have a second, equally important characteristic property:

109823/1751

tionainittel or anodic effect must have sufficient strength have ma ,, replace the au remove metal ,, without attacking the base metal or at least slow to act on this · There are three basic ways "that the achievement of such a selective attack on the deposited metal enable - without unduly attacking the carrier metal?

■■. · ■■ ι

1 ο The metal to be removed must be electrochemically much more active than the carrier metal. If, for example, it is a question of removing zinc from a steel beam, there are a large number of usable solutions ₉ since there are numerous electrolytes ₉ in which zinc is more electrochemically active than steel,

One can use a complex-forming agent, a chelating agent or a closing agent, which is more effective against the excess metal to be removed than against the carrier metal. Activity of the metal ion to be detached decreases in such a way that they themselves convert relatively / noble metals into relatively active metals _e . For example, gold from the crccscji Ansa.h3 vr.n TJi ftVtrolsrten is a s ^ hi * noble metal ₉ in the presence of excess gyanide ions, however, it becomes a relatively active metal and can easily be detached from a large number of carriers /earth"

109823/1751

6216 34

The BntmetallisierungBlösung 3o One can Setsen an inhibitor su "preferably, ζ 0B ₀ by" chemical sorption "or by physical adsorption, reacts with the support" For example, tend to have a Ansahl of electrolytes and anodic Bntniekelungssystemeiij which are suitable for rapid Bntnickelung ₉ dasu ₉ and the copper absulösem If you want a Entnickelung tone "perform a copper support by means of such a bath it is necessary ₉ an inhibitor P _{zu25uset2sen's} the not the effect of Bntnickelungsmittels" beeinträehtigt _9, however, chemically or physically in more = industrious manner the copper carrier. " Organic or inorganic Shio compounds are suitable for such an application »

As already erwäimt is for EntHietallisieriing a (tecydations * medium erforderlicho This oxidizing agent may be either a chemical oxidising agent that. Is present in the Entmetallisierungsiö · = k solution (Bntiaetallisierung by immersion), or the result of Yervjrendung an electric current (anoäische ERtmetallisierung) seijäo Han applies the two © EntmetalÜ "sierungötypen to" each -of them advantages and ITachtsile has _β Xm average, in industrial practice _p tmd Although .Both in aiaerikanisehen and in the Europeanized = · <ai © ^ jatEaetalliBierwagen äurcsh immersion - "in greater than. the ^ nodic ^ bataietallizations ange \. ^r endsto The main reason foap dies.® Fact Xiogt probably in ^ that.

3/1 TS T

it at a Burehführtmg in ;, industrial standards for Eraie ™ development of great * Surchsätsen difficult _iet's an anodic © Entme-metallization as a Eiitmetallisierung -by immersion öurehauführen "

Werdexi detached from all metals must Nickel most commonly _9th since the nickel is very often used as a decorative surface in addition to chromium. StShI ₀ copper, brass, aluminum and j | Zinc to corrosion resistance makes' ₉ "with hinsn .kommt9 that Hiök © lüberaüge-hard und.bei numerous Terwenduagszwecken over on the one Korrosioii resistant _o Am on the other is ßrund äBxini that DI® automation ago. Salvano" piastilE-lnstaltexi and -Vea? Wön.dung. Yqh 8 @ hr shining -Kickelausgleieiisüber ^ ügesiff which neither "an abrasive Pc-lation nor a Snäbeliaaälung- require _v that nickel-plating process a designed ■" as the beginning " ^: the Ternickelungstech« so ate the crowd © the committee pieces ^ which consequently © nt- -

Some, of the first debris removal agents, were in the form of diving boars asagewendets aie worked on different "combi" -

many years the nickel-plating technology which is the largest has found attention that 'anodic © "use of sulfuric acid ·. During the last.-TO-years; but has developed by diving again a very great® meaning ", attained

Modern immersion baths are generally based on organi = see oxidants and become susanimen with alkaline .Msung-for..development & development-of steel or ssusa seeds with acids solutions at «? De-nokelung- iron brass and copper used- ■

Fife ⁰ oil © decorative Met aiii sieving of steel v? Ird sometimes nickel directly on the steel and sometimes, deposited on an underlayer & UB copper. Consequently, the Satnislreltiri ^ sometimes must be designed _p tess sie-das-, peel off mokel _s ^. without yet-to carry out an attack on the copper weäer the steel ξ it may also be the - case occur ₉ that both the nickel and represents & Kiipfertiber be replaced tig mUsfsn without IASS etafeei exerts steel angegrif.tea. becomes _θ

The modern Bintauch-Entnickeluiigsbad are often based on organic-oxidizing agent ^ - A particularly interesting group peer organic Terbindungen is the nitro group C = IOp) _o -The e is, very slightly reduced ₉ whereby as result, the ab

Metal is oxidized »Although there are considerable quantitative differences _9, organic nitro compounds have _{a large number of oxidation potentials 9} which are suitable for a deniclce limg ,, Jsäoüh is ancla drlß ■ T.Hn ? v connection in the Entnickelungslösung Ύοη important ₉ because "aahlreiohe ■ organically © nitro compounds only begremto solubility ■ in water b © sitS0a _o It is generally required _p pages · -. k © tt © n" aaaubringen ₉ which-the HitrobenssQlgrimöstruktiir löslieh

BAD ORIGINAL 23M7S1

- Ί

make ο Yon such lösliuMiachendeii Griippsa seieii the carboxylic acid group (--COOK) that Aldelayägruppe (-GHO) * ^ ^r sulfonic acid (SO ^ H), the hydroxyl group (-OE)> ÖKlorid ( "01), Bromiä (Br) or something like that. In the more recent American 3? Ieseri £ th 2649 36I ₉ 2 69S 781, 2 937 940 imä 3 102 803, islands are given about certain connections of suitable connections and in particular about the following organizational connections s

Connections

O-, Bi-, p-Kitrochlorobensol
o-, m ~, p-nitrobenzoic acid

o- ', ia-, p-Mtroanilia o ~ ₇ in * -, p ~ Kitrophenol Nitrophthalic Acids 2-lii'br or esor a

2 ₉ 4 ~! Dinitroresoreiii 2 * 4 1 6 ~! Srinitror @ sorcin o -, * mj p Q ~, m-, pS

ropane:

Hitropesitaa ©

tris
nitrometfcan

As from "the

f that the

as well as

ge--;

7175.1

, nitroaliphatisehen as are "Pie latter" have only one begrenate in water! löslichkeit? the Molelatlargewichte the nitroaliphatiseheii Verbindimgen are very high ,, then be-Biteen e'e just a begrenstes 33ntniakelnngs, v-ermb'gen _s during these compounds hai low molecular weights are very volatile *

the Entniekelung of steel articles have al "=-earth solutions! than 3m interessantesten proved (acidic L8-öungen have die.neigung * attacking the steel)" Ba forms, however, the nickel in alkaline solutions an insoluble Eyäx ^j oi ^ & "which tends vi © i% ere Entnickelungswirkung to prevent j, it is necessary * a complex forming it iÄit ^ el or egg "Qhelatisierungsmittel for nickel zussusetaono Saubestre (" plating "45 ₅ 479-485 (1958)) has the following Oxyäationspotentialwerte in Reference to fickel in the presence of various complexing agents and ßelating agents at a pH value of 11 calculated

*! "28 Y diethylenetriamine + 0.95 V

+ 1.17 T ethylenediamine + "0.86 V

· * · 1-04 ^ "ammonia ψ 0} 86 v

Acetylacetone + O ₉ 83 V

The means listed by the TOURISM are the most effective and effective fias the cheapest the oyanide, which is usually nickel following complexes

" BATH

forms-: M (CIf), "" and M (CH)> ""% As well as in ■ industrial Oelating agents used on a scale come in Be = amines costume, which with Ückel following GheXatkQQUiez Mldem

Ear

CH,

'Generally-used. one ^; fön in industrial practice for Elitnickeln steel not _f 'oxydieri) a2? em steel and magnesium ,, the Entketallisiex-ungsmittel from 2 yp? the Ojanids * during the Entnißkelung of copper and brass or ^ on workpieces of steel and Kupfer3. alloy @ n contained at once, the demetallizing agent of the amine ^ n? is used »

In more recent times one has passed over to. Ammonia - the grain of "plexblldendes'iAittel'-in denniokelungfjiamittel bu use / ends, which for :? die Ihtnieke3.ung vü? j. Steel ₉ copper xmd brass are used «This is the basic principle of German patent specification i 163 117. In such baths the complex formed probably consists of ITi (IiH ^) / ^r .

No other inhibitor is suitable for the nickel removal of steel. Required · However, inhibitors are necessary

1018 23717S1

.-- ■■■ * - 10 « ^:

16-2 ΊΒ34

if you remove copper or brass. vrf.il »The most common inhibitors are! 'hioverMndimgen, as they are listed, for example, in the ÜS« Patentsehrift 3 102 808. The most frequently used compounds are those of categories 111 (1) V 1.11 ( 2). IT (I) ₉ V. (2) «nd YC3) in columns 1 and 2 of the above-mentioned US patent letter ·

Below ψ & ταβη typical examples of the above JSntnickeliinggliader diskutierten- "types specified.!

Gyanide type Mitroaromat .Amin type Mtroaromat Ammonia ^ '- Dyp s Hitro aromatic 60 g / 1 - HaGI Ethylenediamine ' ^: ' 3ra ₄ 0H-3 ^ Bimg .- (285fiti 120-180 g / 1 IaOH temperature (IH ₄ ) ₂ S0 ₄ 0 »25 g / 1 temperature temperature 60-75 ⁰ C 35 g / 1 65 s / 1 60-BQ ⁰ Q 4-5 g / 1 5) 250 ml / 1 100 g / 1 60-8O ⁰ G

,, BAD ORiGJNAL

10982-37-17-8 f-

If one uses inhibitors from the £ yp of the ^ Mo ^ TerMndimseiij so are preferred * # eisö 0.1 l) is 0.2? ί from TerMadmigen in the mentioned above Categories used. ·

The following comparisons can be made between the three types of Set up alkaline, nitroaromatic eatniolinig breads?

1. The oyanide type is much "cheaper than the amine ^ lTypc, eein" Gastehungsprels is comparable to that of the Aminoniak ^ yps.

bar· · . ■ '.. ■ ■ - ■. ^: ■■,; ■■■■■ "'. V ■■',

2, The 4min-5? Yp is more stable at elevated temperatures _y while the ^ Mnonialc ^ type is less stable because of the volatility of the IK ^. Especially to the 0runde this is mb'glichf in the bathrooms amine ~ IYP faster entniekeln _e

- ■ -.- ■ - i

3 * The amine-type bath has the lower tendency that | Attack Iragers while the Amraonia type control

Inclination. ■ --.-. ■■

4 β The gyanide-type bath generally leaves the work behind piece in focus on ^^ a new © galvanoplastic treatment? img in better condition »

5 «Although · they mean in a two-way manner

are inhibited, take the baths of the Min- and iusmoniafctyjL- ^

10a823 / 17S1

1tf21634

neither copper-to-brass, while the baths from Cyenid-iByg _ generally a considerable attack on these metals exercise «,.

60 With regard to the discharge of the used baths into the sewage system, the gyanide «3} yp is problematic, while the ammonia ~ T; n? not too big s problems throw t _o

The present invention 'has a new and improved composition of the target, which is suitable for EntnickelungvonStahl, copper ₉ brass and alloys more arid "

The in question Entnickelungszusamraensetzung attacks nen this! On rager. It doesn’t use copper and brass aa _s . v / if a composition of the "cyanide type" does this, nor does steel, as is the case with a combination of the ammonia type. Your Anwendungskostea are either identical or are un- "terhalb from those of the three above-discussed types and considerably below those of the amine IYPS-i In the fiction, geraässen composition no wastewater problems occur, so as in the Oyanid ·» and amine ^ iDypen is the lall ■■ It is "not unstable at elevated Semperaturen as the ammonia-type and, albeit to a lesser extent" of Cyatiid ~> Syp _e is neutral or in comparison to the strong alkalinity of the other three types, only slightly alkaline,

; '- BAD ORiQiiMAL

634

It has been found that Klan can provide a precise and improved nickelizing agent of the type indicated above by using a nitroaromatic compound as an oxidizing agent, a soluble ammonium salt, certain carboxylic acid types as complexing agents, and a shio compound ₃ which once "serves" to inhibit the attack on the copper-based carrier and to accelerate the de-dislocation of the copper coatings which have been freed from sulfur! _s used «Optionally, you can add other ingredients, with- | For example, wetting agents to promote the uniformity of the effect as well as additional inhibitors for steel ₉ such as, for example, borates ₀ The composition is adjusted to a pH value: * of a maximum of approximately 7 to 8 ^ * 5 (electrometry) at normal temperature «. The optimum pH «value for other temperatures is specified in more detail below. The nature of the baths according to the invention is completely different from that of the compositions described above and generally used so far.« They contain neither oyanide nor amine »They contain no free ammonia added more like it is with the Ainraoniacal baths, dey Pail, »On the other hand

whereby

According to the invention, ammonium salts are used _s / at the pH values at which the baths in question are operated, η ± ΏΒ ijjeT'ir'i-i "hg -TTv -. ^ rn.lysfi f.'ptr. ΑτΛττ? Ί5Τί1ι: τΐ: 1ηηβ "" nrfr.-lgt- Bifjo has a noticeable ammonia odor in the vapors immediately above the bath during its operation. Thus, it can be concluded that the mechanism of action

- ■■■■ - "BADORfGiMM = -

982 ^ / 1751 r

The baths according to the invention cannot be compared with those of the classic ammonia baths known to binders, in which nickel is dissolved in a complex form, probably in the form of iron Hi (HH * J · / ¹ **, namely by the presence of the itamonisk, as can be easily recognized by the characteristic "blue" color. In contrast, the clot dissolved in the baths according to the invention shows the characteristic green color of the complexes which the nickel forms with the carboxylic acids, although an icleine amount of ammonia in the erfindungsgeraässen Bädexn sugegen be indicative, this quantity plays only one minor role "while oils! puncture of ammonia in a Ämmoniakbad essentially consists in forming a complex with the ... Kiekel au. a _ quantitative definition of this difference is below specified.

The inventive baths contain Kltroaroniaten of the type "such as described in US-Fatentsohrlft 2,649,361, and in a Meng © between about 30 and about 120 g / l _o They also contain certain carboxylic acids, vorsugsweiee a) tricarboxylic acids, which correspond to the general formula HOOC - R ₁ - R ₂ ~ ^R 1 '"COOH, where R ₁ and R ₁ ' GOQH

a -CHg- or a -CHOH group, while R _{2 represents} a -CH- or a -COH group, as well as their salts, b) a dicarboxylic acid which has the formula HOOC- (CH ₂ ) _n ~ GOOH speaks, WGrin η is a number between 1 and 4, and dore> i

BATH ORIGINAL 109823717S1

c) Qt * -Bydro2cy- * Eiono ^ and: 33i - c "aj £ boii: öäii ^ en. _? ;, v / elche di« E ₁ -.- CEg) ₁₁ -GHgGH -GOOH beeiteezi, where R ₁ a -GH ₂ - or "GHÖH group" are my whole range between 0 and 4, and their salts are &.) HisGhimgen except at least two of the groups a), b) and c), the above contact inserted etat in amounts given Säiirön, the v / ground between dangerous 45 and about 155 g / l * ausgedrtlcliit used in freier.Säm? e, corresponding odes ¹ Salzinengen "

■ ■ '■ ■ ■ ■ ■■■ "■ ^r:::;:. ■■ - ■■ ^{V: -:} - ■' ■■■■ ■■■ * Although the conditions are not lcsitisch ^ _t gets dull The best results when the ratio of the nitroaromatic compound to one of the satires given above in the bath is between about 1: 1 and 1.2. The baths must also preferably contain ammonium ions in an amount between about 15 and about 60 g / l contain · It is advantageous to introduce ammonium ions in the form of amraonium salts of the carboxylic acids given above · Optionally, one can use soluble ammonium salts, for example the oil chloride, carbonate or sulfate ο 3) the baths also remove the types of compounds of the S & io -s 111 (1), 111 (2), IV (I), V (2) and _Vf5)? as described in US-3,102,808 Eatentschrift defined SINU ₉ in amounts between about '0.075 and 3.75 g ungefäiir / l

, Wetting agents ι can, such as / Stll of anionischsn 3 be yps attgegen in small amounts, beispielsweiee swiachen approximately ^0: 375 '.and 3 »75 g / l. ¹ IHiE the treatment of Btaiil can gegebenenfallö additional iiihibitorens as Tjeispielsweise borates, in Uengen from 0 to 15 g / l are added "-. ".-: - \ - ^: .:}; - .-. /" ■■ -. "- ^: \.", = —- * '■

^: "■;'-^;; 109823/17 $ 1 ■■ - ■;

- ■ ¹ «V 1821634

pH range äev erfindungegeaiäsöen Entnickelungsbüde; - 1st, as indicated BacheteheB'l "is" on certain pH _limits's -and swas? on the values at which the steel is attacked - since it is a progressive effect, it is difficult to adjust this "pH value with accuracy". It also depends slightly on the temperature "from the appended. gr-aphischoii representation in which the elektrometrisöh measured pH value on the ordinate and the temperature "t · door in ⁰ C .. Araf the Abssisee is applied se IGT the approximate pH value at which the steel is attacked "From the illustration it can be seen that the lower, electro-aerodynamically ..-..- measured permissible pH range extends from approximately B ₉ Q to 7 _s 0",

The upper pH-x range is determined by the point at which the hickel stops forming complexes with the carboxylic acids
and to enter into cosiplex formations with ammonia ". This transition can visually perceived - are as di © öarbonsäurskoaiplexe grün'sind 9 "während'die .Ammoniakkomplexe are blaiigefärbt" The Parbänderung © rfolgt not abruptly but progressively »» nerhalb eia.es pH of about liereiches O ₈ 3 units ", Of the"
pH <= "Vfer" t, at which the transition takes place, depends considerably on. the temperature "from _s - since the ■ stability constant. des amnior - '^ rraiona at dea? Hydrolysis in aqueous solution strong "•! Kjmperaturai-Ijä'igig is ο The graphical Darstellung.zeigt die.pIMfrerte m depending on the temperature, which bsi the 'transition de'a JJickel-

"" bad orig ^{| NAE}

1011634

complex (Carboxylic Acid CoMple & in
At pB * "values that are above the Hegel's values, which correspond to the transition zone", brass and other copper alloys are attacked by the nicotine bath! It is consequential with regard to the following: for an optimal selectivity, d <, h _e a maximum distinction between the speed and the speed of access to the

Made of St ^ aI, copper and copper alloys meckmaealg, work in the "caution of the upper pH range". In the graphical representation the curve corresponds.

0.1

a bit of such an optimal condition.

The optimal recommended pH values are given below

Temperature ( ⁰ O) 20 30 40 50 60 70 80 pH (electrometric) 8.4 8 * 1 7.8 7.5 7 * 3 7 * 1 6 _S 9

In the yo2: standäsn! Pabellu are the tiiSgegöbsnszi gH «>v7ε;χ-ί;<5 ale = * a few who are gemegöon at the corresponding temperatures

She relative sizes of the interval suläsßigcm o-bere-n- -liK value are from AEEN St & bilitatskcngtanten gegenübei? && £

1634

calculate · !; υ and av / ar τοπ Aamoniiaaiionen "ia wäßigen and they are described in BjerEUB's work "Stability Constants *" aindi.

The K values for 15 to 50 ° C are experimental values _r . while those for S> Ö to 80 ⁰ G are extrapolated according to the principles given for thermodynamics, »where an arbitrary value of

as the upper value would be accepted, above which one of it can speak »that the Torhavidene free ^ JnmoDlaSmeEge is the result of a continued ear © ittmd en transformation, starting from a Solution j in the NEW mainly la 1ο3Ώ3ΐ of not hydroiy-

-r Fieitel

duTnioKcii vorlis-gt »dsrstellts» ähv ^ nfl mainly --in the form of complexes with obarboasaiaren. Mc ■ isu. there is a mainly immonial solution «Pie K values are those v / is they re-enacting saga give aincls

BATH ORIGINAL

2.3 / 1 ¹ TS T

τ (° α)

1OgK

9 »..70

10 g K 8.16 8.05 7.92 7 _e 8S 60 8.29

Msn has v «2? E« e2at » ®3m®

given values and the 'vie-aeUeji sueteilen · As from the see eats, 1st you

BUfrledeneteilend. Above & ± m®s Provisions, des

danger 0.2 pH-> iä.nheit@m

K values calculated pH <= ° W © rt @ o M, mw Be case, there be

the pH ~ W®rt @ b @ i veniger are, vi © di @ visual Bee ^ lLaHSffisuiea i; upper admissible den 'vor * stthend ψψ, · des? Disgusting only

®tt φΙώθγ leafüeifatur ^ ron 50 ⁰ O

Seaperatur are al *

t ^ s die Hi © i: slkc3ipl © s: oi ya, im «. They on the Qteimdlai; © der kamt teilve £ e @ tfssLalb

^ M '

Huheron goes out

will.

_f he at

108823/1751

Even with values .

0.1

a progressive aranonia krerluet occurs, in particular at elevated temperatures, namely because of the considerable partial vapor pressure above the solution. A progressive decrease in the pH values of the solution occurs during their use. Se is nrcok-wise, the valuation by adding the ammonium salts specified above and not added by adding ron Regenerate ammonia by yourself · With such pH levels one can adjust the pH either at operating temperatures or at Determine the usual temperature by using the graph, from which the desired pH value setting at the operating temperatures can be figured out.

) The temperature can be around 62 ⁰ O between normal ambient temperature. Above 82 ⁰ C, the Amnoniumsalse very rapidly hydrolyzed "said considerable AmeonieJcmengen be gesetet in freedom; characteristic changes in the bath occur, which cease to be “effective” in the sense according to the invention. For economic reasons, when the bath is carried out on an industrial scale, the optimum temperatures are between approximately 70 and β2 ° 0. '. ·'""'' ■

^r GAD ORIGINAL

109 * 23/1751

~ 21 «.

16 ^ 1634

After Entnickelung, none of the support made of steel, copper or a copper alloy in a state indirectly thereafter accommodate un '' a new electroforming plating, and that, therefore, there have been formed from the Entniekelungslösung coatings with an inhibitory effect _o steel girder can by an anodic electrolytic pickling treatment in an anodic electrolytic pickling bath _9, as is normally used for steel, followed by immersion in an acid bath (which contains, for example, 20 G @ w _o $ oil), again for the inclusion of a new galvanoplastic Plating, made suitable «Copper as well as alloys based on copper can also be made susceptible to renewed absorption of a galvanoplastic coating by immersion in acidified (for example H ^ SO ^} chromic acid solutions.

Di © Scfindung therefore a new üäitnickelungsbaä for metal "carrier to the content, which is characterized in that there is a nitro aromatic compound in an amount zHilacheTn about 30 and 120 g / l> a carboxylic acid or a salt of such an acid in a" on the Amount related to acid between 45 and 15 g / l »an ammonium compound in an amount related to the ammonium ions between about 15 and 60 g / l and a Shio compound in an amount between 0.075 and about 3.75 g / l l contains.

BAD ORIGINS.

109823 / 17S1

falls within the scope of the present invention, a new BntniGlceliingssiisaramensetsung consisting of a dry mixture of about 13 to 64 wt _e $ a nitroaroraatisehen compound, about 20 bie 72 wt. ^ a carboxylic acid ODSR a Salses a carboxylic acid-»about 8 to 44 wt., $ .Ammo "niuroionen in the form einsr iiajcaoniumverbindung and about 0.02 bia 4 ₉ E GeWo ^ a Shio-Yerbindung is · as already mentioned above, are as nitroaromatic Yertinäungen preferably orphan those compounds used" the 2649 in the US 3? atentsöhrift 361 specifies ßinä. The precautionary set of nitroaromatic compounds are sodium m-nitrobenzenesulfonate and

Of the Tosgugsweise carboxylic acids used are citric Adipinsäurej mentioned ₉ gluconic acid, glycolic acid _p Milchi3äure, Maleinsäurej succinic acid and tartaric acid "

"Of the Shio compounds that are preferably used, the following may be mentioned (dhiourea _f sodium diethyldithioo-carbamate, mercapto benzothiazole ammonium thioeyanate and aramonium thic sulfate".

Here are some examples of the invention without it au besohränkön, - ■

BATH ORIGINAL

109823/1781

example 1 Menace (κ / 1) component "--41 ... · nitroaromatic compound 71 Anunonium salt of a carboxylic acid 1.25 Thio compound 1.25 Alkyl aryl sulfonate 5.6 Alkali barates (pH: as in example 2) (Temperature: 82 ⁰ C)

Introducing identified ingredients are ι dissolved in water, the thus prepared bath for a% tnickelung of metal substrates such as steel, non-oxidizable steel, magnesium, copper, brass IMD copper alloys ready · The bath temperature is vorziagsweise to about 82 ⁰ O held »You find that one on the se; Well-prepared nickel plating solution that removes the Uiekel from the metal supports at a rate of approximately 0.025 mm Hickel per hour. The pH value of the solution is kept at normal temperature, preferably at 7.8 and 8.2 ",

AtSDiel 2 109823Π751 Quantity (g / 1) component 82 ₉ 5 nitroaromatic compound 142.5 Ammonium salt of a carboxylic acid 2 _f 5 Ihi connection 2.5 Alkyl aryl sulfonate 11.25 Alkali borates.

²⁴ "16 * 1634

pH (if necessary adjusted to 8.2 with the help of (ML) ₂ CO ₅ at normal 3 temperature)

Temperature * 82 ⁰ O

The preparation of the solution occurs essentially NaOH to the procedure described in Example 1 _β For a -preferably employed working temperature of 82 ⁰ O is a metal support with a speed of about 0 _f 048 MRA / hour accomplished by the above described solution, the Entnickelung.

To regenerate the solution, it is advisable to use the • Sr to produce composition in the form of a powder mixture «The The mixture given below enables the production of a bath according to Example 1 if 120 g of this mixture are used per liter and the production of a bath according to Example 2, if 240 g / l of this mixture is dissolved «.

Component quantity

nitroaromatic compound 54

Ammonium salt of a carboxylic acid 59

3? Hio «Yerbinäuttg 1

Alkyl aryl sulfonate 1

Alkali borates 5

BATH 109823/1751

It vrlxu. a Ifeitrii ^ ß ^^ gß ^ ß'ös as it is described in Example 1, produced _? indeia sodium a-nitrobeiizole sulfonate is used as a nitro aromatic compound »

A nickel plating bath, as in Example 2, is rubbed for 3 seconds is, produced, by acting as a nitroaromatic compound Hatriiua-ffi-nitrabensoat is used, "

BeiSDJe ?. 5 .. ...

A nickel removal bath is produced, using as nitrcaromatic Connection Natriura-m-nitrobenaolsullOnat !, as iiraao « niurasalz ansmonium adipat and, as a Shio compound, thiourea yerv / eiidet is «. . .

Example 6

There is a bath, as described in Example 2, manufactured ^

represents, whereby, sodium mnitrobenaofulfonate as nitroaromatic compound, ammonium citrate as aramonium G3l. {s and chiourea as thio compound we use ^r 2 _o

Example 7

A bath is prepared as described in Example 2 is, where the nitroaromatic compound is Sodium-nitrobenzoa-J ;, as the ammonium salt ammonium gluconate and as the ithio compound Ammonium thiosulfate is used. __.—. »

BATH

.r

109823/1751

BeJST)] LeI 8

A composition _P is produced as it is written in Example 1 ha ™ *, with ananotium nitrate as the carboxylate and ammonium thioGyanati as the dhio compound. as alkali borate boras: and as wetting agent sodium methylnaphthalenesulfonet is used.

Example 9

It is a composition as it is in Example 1 is written, produced, with ammonium gluoonate as the garboxylate, All alkali borate borax is used and sodium methylnaphthalene sulfonate is used as a wetting agent.

Example 10

It is a composition, as it is in Example 1 = » is written, using thiourea as a thio compound, ale alkali borate borax and as a wetting agent Sodium methylnaphthalene sulfonate is used *

Example 11

It is se a Eusaimaensetzung ₉ as it is written in Example "J OS", prepared using as Ammoniumglykolat carboxylate, is used as alkali borate and borax as a wetting agent Watriummethylnaphthalinsulfonat.

Example 12

There is a composition as it is in Example 1 ~

109823 / 17S-1

Bohrleben is produced using sodium diethyldithioeerbaraat as the thio compound, borax as the alkali borate and borax as the be «* wetting agent sodium methylnaphthalene sulfonate is used »

Example 13

Ee a composition is made as it is in Bei, «· game 1 is described, with ammonium acetate as the carboxylate, Borax is used as the alkali borate and Hatriuiainothylnaphthalinsulfonat is used as the wetting agent.

Example 14

A composition is prepared as described in Example 1, with sodium thlosulfate as the thio compound and borax as the alkali borate, inter alia, as wetting agents Fatriuismethylnaphthalineulfonat is used.

Example 15

A composition is produced as described in Example 2, wherein the ale carboxylate is anonium tartrate, the alkali borate is borax, the benetsucgar agent is atrium methylnaphthalene sulfonate and the nitroaromatic compound Sodium ~ m ~ nitrobenaolsulfonate is used

Example 16

A combination "as it is lived in Example 2" is produced, with all thio-compounds hatriUT; thiooyanate, as alkali borate borax, as a wetting agent

109823/1751

imd as nltröarOmatisöhe

BeJBplei .1%

Ingredient quantity (g / l)

nitröäraißäMöölie YerMnöxaig 41.5

Berns teiüisätire 56

AminoniuKioartoonat 45

Ammonium thiocyanate 1.25

Borax 5 _S 6

Katriuraräe thylnaplithalinsulfonat 1,25

pH (if necessary with the help of

.of (IfH ^) 2 ^c ^ 3 ^ ³⁶ ^ normal temperature

set to 8.2)

üJ Temperaturs 82 ⁰ O.

Whiskers 18 Lot {/?/!} component 82.5 nitroaromatic compound 112.3 Succinic acid 90 Ammonium carbonate 2.5 Ammonium thiocyanate "j -1 ^ OK Bors * 2.5 Sodium methylnaphthalene sulfonate

pH (if necessary by means of

(EH «I ₂ CO, at normal temperature

set to 8 _$ 2) Temperature: 82 ° 0

1Ö9823 / 17S1

The powder mixture given below results in incompatible?

the bath described in Example 17 " _f if you have 150 g / l and

the bath described in example 18, if you dissolve 500 g / l on «>»

component Sfenge (wt. ^; nitroaromatic compound 27.5 Amber acid 57.5 - " Ammonium carbonate 50.0 Amraoni ^ jföthiocyanat 1.0 borax 5.0 Hatriurame thylnaphthalene sulfonate 1.0

As a nitroaroBiatic compound, either Hatriura-m ~ nitrobenaolsulfonate or 2fodium-m- = nitroben5ioate used,

Example 1 $ Amount (r / 1) component 60 nitroaromatic compound 56 citric acid 41.25 Ammonium carbonate 1.25 Ammonium thiocyanate 5.6 borax 1.25 sodium methylnaOththalene sulfonate

pH (if necessary raittels () ₂ 00 ^ at no3? painter

₂ ^
set to 8.2)

Temperature: 82 ⁰ C

109823/1751

Example 20 EbbbsJLb component 120 nitroaromatiscliG compound 112.5 citric acid 82.5 Ammonium carbonate 2 _f 5 Ammonium thiocyanate 11.25 Borax, 2.5 Sodium dimethylnaphthalene sulfonate

pH (if necessary using

*) gC0a at normal temperature set to 8.2)

36, 5 34 25th -1
I. 2, 5 1

Temperature s 82 ° C

The powder mixture given below gives an approximate result the bath 19f when using 165 g / l and the bath according to example 20, if you dissolve 330 g / l

Beatand part of the crowd

nitroaromatic compound citric acid

Ammonium carbonate

Aiaiaoui uiaihlocyauai borax

Matriuramethylnaphthalene sulfonate

As a nitroaroinatieche compound either benzenesulfonate or sodium m-nitrobenaoate

10982.1 / 1751 PAD original

31 = 1821634

Example 21

lot

nitroaromatic compound pH (if necessary: 26.25 enp; e (g / l) Sodium citrate 101.5 52.5 Ammonium carbonate 41.25 202.5 Thiourea 1.25 82 _f 5 borax 2.5 by means of 11.25 (HH ^ gÖOu at normal temperature set to 8.2) * Temperature 82 ° C Example 22 Component M nitroaromatic compounds Hatri «umcitrate Ammonium carbonate iEhiourea Borsx

pH (if necessary using

(HH ^) ₂ COk at normal temperature _

set to Sf ^.).
temperature 82 ⁰ O

The following powder mixture roughly equals the bath Example 21, 7 / if one 180 g / l and the bath according to Example 22,

if you dissolve 360 g / l.

10982371751

Menßö (Gevsr. F> \ 1621634 component 15th nitroaromatic compound 57.5 *> Efatrium citrate 23.5 Ammonium carbonate 1 5? Hiourea 5 borax

Either sodium-ra-nitrobenzenesulfonate is used as the nitroaromatic compound or liatrium ^ ra nitrobenzoate used

Since neither cyanides nor amines are used according to the invention, it is clear that there is no relation whatsoever to these two types of nickel-removing agents, which have been most commonly used up to now *. The bathrooms according to the invention differ furthermore from the ammoniacal "EutnickeIuUgMbKr". arn, even then «if, in the event of an accidental decomposition, they cr5v / as Release ammonia

The Austrian dennicke lung baths contain considerable amounts of two basic substances, ammonium salts and ammonium salts. The baths according to the invention contain only considerable amounts of ammonium salts. This has a fundamental undertaking of the oheird & uhea Wii'kungsv / eiöe öer av / ei BUdes; 2. \>: A consequence., ' . In the py.llr of the ammoniacal de-nickeling bath, the ammonia forms a complex of the formula: Ui (SfKv) these conditions occur continuously!' ATma

· ORIGINAL BATHROOM

1 09R73 / 1751

the © mpsraturen on · at the elevated 5? and the strong alkalinities, in which the aamoniakalische Entnicfcelungsbad works is "unavoidable, so that the balance of the principal constituents of the bath greatly disturbed eating" Tuck Slvdehgewichtsstörung in a reduction in Entnickelungsgeschwindigkeit and / or a strong Corrosion through Sins See and / or an even attack on the steel support. A fundamental difference lies in the fact that in the baths according to the invention the Nieksli.on forms complexes with certain carboxylic acids, resulting from the characteristic green color · Consequently, the accidental loss of small amounts of ammonia through volatilization does not affect the functionality of the bath, so that neither the rate of nickel removal is disturbed nor an attack on the steel »copper or copper alloys» provided that the pH value is at a suitable value is set «

BATH

109823/1751

Claims (8)

Claims 1, bath for nickel removal from Me tall carriers, characterized in that it consists essentially of an aqueous solution of: f} a nitro-substituted mononuclear carbocyclic aromatic Compound. Which has at least one ^ -NQg group on the benzene ring contains bonded and a substituent which is water-dissolving acts., the compound being present in an amount of "JO to 120 g / l is, ' 2) a complexing agent for nickel ions that was selected the end: a) tribasic carboxylic acids of the formula: HOOC-R ₁ - R ₂ - R ₁ '- COOH 0OH and their water-soluble salts, in which R ₁ and H " ^r denote the radicals -CH ₂ - and -CHOH- and R ₂ denotes the radicals -CH- and -COH- b) dicarboxylic acids of the formula: HOOC- - (CH ₂ ) - COOH or their salts, in which η is an integer before: 1 up to and including 4 means c) a-Hydroxymono- and -dicarboxylic acids of the formula: -CHOHCOOH and their water-soluble salts, in which R _{1 is} hydrogen and -CQQH, Rg- is ⁰ H ₂ - and -CHOH- and η is O or an integer from 1 to 4, inclusive, and d) mixtures of at least two of a), b ) and c), the complexing agent being expressed in an amount of 45 to 135 g / l » ^ ORIGINAL New as free acid, is present * 3) Ammonium ions, which are "present as water-soluble ammonium salts, selected from the ammonium salts of the carboxylic acids and ammonium carbonate specified under 2, in an amount which - is sufficient to the .pH value of the bath, within the range of 6.8 to 7 * 0 *> A ^s below a predetermined higher pH value at which the nickel ions 3m are essentially no longer complexed by the carboxylic acid and instead are complexed by ammonia, as indicated by the change in the bath color from green to blue, and 4) a thio compound which, in aqueous solution, supplies sulfur ions in which the sulfur is in a -2-oxidation state and which is present in an amount from 0.075 to 3.75 g / L, wherein r.er pH of the bath within the pH range specified above lies, exists. 2. Bath according to claim 1, characterized in that the ammonium ion is present in an amount of 15 to 60 g / l and ice is water soluble Ammonium salt is supplied. 5. Bath according to claim 1 or 2, characterized in that the nitro-substituted aromatic compound sodium metanitrobenzosulfonate or sodium metanitrobenzoate is the complexing agent under adipic acid, citric acid, gluconic acid, glycolic acid, Lactic acid, malic acid, ^ succinic acid and tartaric acid and their water-soluble salts is selected and the Schwefelverbindun.p; of thiourea. Sodium diethyl dithiocarbamate. Mercaptobenzothia7; ol, Ammonium thiocyanate or ammonium thiosulphate selected viird. . 4. bath - according to one of claims 1/2 oder.3 * characterized in that that the weight ratio of the nitro-substituted aromatic compound to the carboxylic acid between 1: 1 and 1: 2! '. '■ · ___ ^ ■ "■" '- 109823/1751 IbZI634 5. Method of removing nickel deposited on a metal support Is applied, characterized in that the nickel deposit on the metal support with a bath according to one of the claims 1 to 4 is contacted and the contacting of the nickel is continued on the metal support with the aqueous solution, until the nickel is selectively detached from the metal support. 6. The method according to claim 5, characterized in that the Metal carrier is steel, copper or a 'copper alloy. 7. The method according to claim 5 or 6, characterized in that the removal solution has a temperature in the range of room » temperature up to 82 C. 8. The method according to claim 7 »characterized in that the aqueous nickel removal solution at a pH in the range from 7 to Jt and '= o - 8.5 / at-a temperature of the solution of 20 G is maintained. 9 A dry composition that when dissolved in water supplies a nickel removal bath, and essentially contains: 1) a nitro-substituted carboxyl! See aromatic compound having a ring which has at least on the benzene ring a -NOg group bonded and a water solution vermitt ³ soldering substituent and is present in an amount of 13 to 6H%, 2) a complexing agent for nickel ions, which is selected from: ■ -. . ; - "- ■■■ a). tribasic 'carboxylic acids' of the formula HOOC- R ₁ -R ₂ -—- R ₁ 'COOH CQOH and their water-soluble salts, in which R ₁ and R ₁ 'mean -Clip- and -CHOH- and R _{2 means} the groups -CH- and -COH- * • '' ", - 1098? 3 / 1-7-51." Bad ORIGINAL 1Ί5Ζ163Α b) dibasic: carboxylic acids of the formula; HOOC —— f CHg) -—— GOOH / ' and their water-soluble - salts, - where η is an integer of 1 up to and including 4 means c) «-Hydroxymono- and -dicarboxylic acids of the formula ;; ' R ^ - · (R ₂ ) CHOHCOOH and their water-soluble salts, in which R _{1 is} hydrogen and -COOH-, Rg is -CH ₂ - and -CH-OH- and: η ΐ or an integer from f to finally U ijejleuttet and;: ^ · d) mixtures of at least two of a), .b) and C) ₄ where the completing agent in an amount of 20 to f? : ^> prepared as a free acid ^ present 3) an aqueous ammonium salt, selected from the ammonium salts of the carboxylic acids mentioned under 2), and ammonium carbonate, which is present in an amount of 8 to 44 % , and 4) a Thioverbindun:?, Provides the fei -containing in aqueous solution pivot ion, wherein the Schwefelrcin present a ^ ^ -2-oxidation state, and ψ is present in an amount Yono ^ OS to 4.0, wobai all Prozentgehälte than weight " ^ adjusted to the total composition are given * *. ' - .; ■ '"-" - = ^".";: - ■ """ : BATH 1098? ^ A 1 7 * 51