DE1496843A1 - Electrodeposition process - Google Patents

Description

The present invention relates to an electrodeposition method of films or layers of nickel and nickel alloys, such as alloys of the permalloy type. In particular it relates to improvements in the deposition of high gloss Nickel layers and magnetic layers of nickel-iron alloys or alloys of nickel-iron with cobalt and / or phosphorus and / or copper,

It is known that electro-deposition is used to create nodular layers from a solution of nickel sulfate, Niekelshlox'id and Prepare boric acid, this solution usually also a wetting agent to reduce the interfacial tension between

909833/1033 ORIGINAL BATHROOM

the electrodes and the electrolyte solution, a friral additive to reduce the residual tension of the Niekelabsehenung and contains a secondary additive to facilitate leveling. So far, the primary additive has always contained sulfur in a form which is reducible under the conditions of electrolysis, so that a significant amount of sulfur is deposited along with the nickel became. The secondary additive promotes leveling, but it also increases the residual stress of the deposited nickel considerable. By properly balancing the amounts of each component in the bath and determining the optimal values with regard to pH, temperature, current density and time it is possible to obtain a shiny, flat, ductile and uniform nickel layer to be deposited electrolytically, but the simultaneously deposited sulfur causes the deposited nickel is very susceptible to corrosive attack.

A typical solution for the electroplating of nickel is known as the VJatts electrolyte. Most of them are ectreplated Nickel deposits derived from electrolytes, the Watts electrolyte are similar, but are dull, grainy and columnar, have a residual tensile stress of less than 700 kg / cm (10,000 psi) and are straight, but flat highly corrosion resistant. So that such Ni? Ikslabscheidung as a decorative top layer or as a layer for

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BATH ORIGINAL

a subsequent metal deposition, for example of Chromium and the like, is useful, the deposited nickel must be polished to a mirror finish. One such polish level is expensive, time-consuming and brings with it the risk of Durohpclierens on the base metal. To these difficulties too bypass, deposits are made two to three times the thickness of the desired thickness. In the case of highly tortuous or complicated shaped documents is likely such polishing is impossible on all surfaces.

Other methods of making electrodeposits that meet the requirements for ductility, gloss, fine-grained layer structure, low stress, leveling quality and corrosion resistance are based on the use of a double or triple nickel system. The initial undercoat is semi-gloss and is obtained from an electrolyte containing a secondary brightener, and the top layer is high gloss and is obtained from an electrolyte containing primary and secondary brighteners. The duplex system is based on the fact that all available high-gloss nickel deposits contain varying amounts of sulfur. This sulfur, which comes from the primary brightener, reduces the corrosion resistance of the deposited nickel. The semi-glossy deposits contain no sulfur and approximate the corrosion resistance of normal matt Watts deposits.

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BATH ORIGINAL

All previously known primary gloss agents contain sulfur and are usually aromatic or aliphatic sulfonates, sulfonamides or sulfonimides, thiocyanates, thioethers, thiocarbonyls, thioalcohols or sulfides. A more comprehensive list of primary gloss agents can be found in US Pat. No. 5,002 (Table III). In general, such additives to electrolytes, although they can give shiny electrodeposits which have the desired characteristics such as grain structure, ductility, and low stress, tend to give electrodeposits that are subject to corrosive attack. The secondary gloss agent used is generally a reactive unsaturated organic material containing oxygen. Typical secondary gloss agents are acetylenic or ethylenic alcohols, coumarins, aldehydes and hydrates and leuco bases of dyes of the Tritah type. The right choice of one. Secondary brightener with a primary brightener for use in a standard Watts electrolyte provides many of the desired properties of a glossy nickel deposit. Due to the simultaneously deposited sulfur, which comes from all known primary brighteners, the corrosion resistance of the deposited nickel is, however, poor.

In addition, it was previously not used in the production of nickel-iron alloy layers or alloys of nickel-iron with cobalt and / or phosphorus and / or copper on flat surfaces

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It is possible to make reproducible films that do not peel, crack, or loosen by themselves due to the stresses created in these films by the electrodeposition process, resulting in poor adhesion of the film to the substrate. In attempting to use a permalloy-type alloy film, 3.B. Ni-Fe-P, on a flat glass substrate which has been made conductive by vacuum deposition of a thin chromium film and then an approximately 300 A thick gold film, 'by electrodeposition processes, the magnetic film tends to break due to the internal stresses that are in the film caused by the electrodeposition process, to loosen, tear or peel off by itself if these tensions exceed the cohesion bonding forces between the vapor-deposited layer and the glass substrate. Electrolytes for depositing films of permalloy-type alloys contain salts with Ni ⁺ * and Fe ⁺ * as sources of the metal ions. Oxidation by air or by oxygen dissolved in the water used to make these electrolytes easily oxidizes Fe ^ ⁺ to Fe ⁺⁺⁺ . It is known that the presence of Fe ^{+ <fr +} ions in nickel electroplating baths leads to high voltage deposits [US Pat. No. 3,027,309, column 1, lines 3 ^ -37, "Stress in Electrodeposited Nickel" by W _S M. Phillips and FL Clifton, 3 ^. Annual Proceedings AES, p. 110 (1947)].

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BATH ORIGINAL

This phenomenon is observed intermittently, and occasionally it is possible to remove the small amounts of Fe *** ions from electrolytes contain «to plate on faultless Perraalloy deposits. However, this intermittent occurrence of the phenomenon is economical in view of the cost of the Preparation of suitable documents and the difficulties encountered in the planned production of. Financial devices are created very undesirable,

Electrolytic baths used for electrodeposition of ferrous alloy films are used are very unstable because of the gradual formation of ferric ions and must therefore be within relative can be discarded a short time after preparation. The useful life depends on the weight of the deposited alloy which also reduces the already short service life by increasing the ferric ion concentration.

The method of the invention improves electrodeposition from solutions containing nickel ions. In particular, it improves the process of producing shiny nickel overlays with regard to the resistance to corrosive attack and also the reproducibility in the production of permalloy films by electrodeposition by delaying and reversing the Significant oxidation of ferrous ions. It has been found that the addition of ascorbic acid or isoascorbic acid to aqueous,

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BATH

acidic solutions »containing nickel ions brings significant advantages. When adding to an electrolyte »which is only supposed to deposit nickel», shiny, corrosion-resistant nickel deposits are achieved and the disadvantages of the previous sulfur-containing primary additives for shiny ash separation are avoided. In the case of addition to the electrolyte "from which deposited nickel alloys" which is Reproduzierbarkelt by a delay and inversion of the oxidation of the ferrous ion transfer verZu significantly improved by _f, and it will be the desired results beiyAntioxy dantlen »such as ascorbic acid and isoascorbic acid, without any deterioration in the desired properties; the residual stresses of the deposited nickel alloy layer are avoided, and layers are obtained which are Will not peel or flake from the metal surfaces on which they are deposited. Through the application of ascorbic or isoascorbic acid in the electrolyte, deterioration of the bath due to the formation of ferric ions is not observed.

Although isoascorbic acid is only about 1/20 of the vitamin biologically C-activity of L-asoric acid, an optical isomer of Ascorbic acid "owns" the two acids are equivalent for the practice of the present invention. A description of the structure and method of preparation of ascorbic acid and isoascorbic acid can be found in the Merck Index, 7th edition,

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ORIGINAL BATHROOM

Pages 106 and 571, edited by Merck 4 Co.j 1960.

The use of ascorbic acid or isoascorbic acid as Sulfur-free primary additives act like most primary additives in electrolysis baths, but the absence of sulfur reduces subsequent corrosion of such deposited nickel films. Certain secondary gloss agents work synergistically with the isoascorbic acid or ascorbic acid used. To secondary gloss agents » which act synergistically with ascorbic acid or isoascorbic acid belong to the general classes of ace- tylenic alcohols and coumarins.

If the primary gloss former In Electroplating baths for nickel deposition using isoascorbic acid or ascorbic acid replaced, all are desired Properties of the known primary brighteners achieved, but leads to the lack of sulfur in ascorbic acid or isoascorbic acid to achieve a highly corrosion-resistant deposit. There does not seem to be a critical upper limit for these sulfur-free additives except for solubility, there is generally no benefit from using them of more than 50 g / l, and in most placement baths practically all the benefits of the presence of these substances at levels of 5 g / l or by themselves get less. It is also useful. secondary

909333/1033

.. to use glossing agents (because of their leveling effects) that act synergistically with the isoascorbic acid or ascorbic acid in the Watts electrolyte or in other common electrolytes such as those with a high chloride content (high eloride), with pluoborate and with sulfamate. Suitable secondary gloss agents> which act synergistically with isoascorbic acid or ascorbic acid are 2-butyne-1,4-diol, the general class of acetylenic alcohols or coumarins.

Objects and features of the present invention thus include:

The use of ascorbic acid or isoascorbic acid as a primary gloss former for the standard Watts electrolyte or an equivalent electrolyte;

the use of a new sulfur-free primary additive to such a standard Watts electrolyte or equivalent Electrolytes 5

the use of ascorbic acid or isoascorbic acid as a primary brightener additive together with a secondary brightener that works synergistically with the ascorbic acid or isoascorbic acid %

the reproducible production of permalloy films by means of elec-

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BATH ORIGINAL

troabscheidj

produce reproducible permalloy films from electrolytes, which contain no or only very small amounts of ferric ions, thus extending the service life of the electrolyte;

the production of thick permalloy films that are continuous and self-supporting when removed from a peelable backing j

the reproducible production of permalloy films from electrolytes that contain an antioxidant j

the production of permalloy films by electrodeposition, which do not peel off by themselves, which do not peel or peel off by themselves, by adding an antioxidant from the group of ascorbic acid and isoascorbic acid for Electrolytesi

the production of permalloy films by electrodeposition from an electrolyte containing nickel ions, ice-snionea and ascorbic acid or isoasoorbic acid.

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BATH ORIGINAL

These and Other Objects, Features and Advantages of the Invention are apparent from the following 'more detailed' description of preferred embodiments of the invention.

To carry out the method according to the invention and to improve the reproducibility of electrodeposition produced Permalloy films, an antioxidant such as ascorbic acid or isoascorbic acid, the electrolyte is added to the Delay and reverse oxidation of ferrous ions in ferrions and increase the useful life of the electrolyte.

It was found that the desired improvements without Deterioration of the other properties can be achieved when the concentration of the added antioxidant of about 1 g Per 1 solution varies until saturation, concentrations over 5 g Per 1 solution, however, the effectiveness of the additive does not increase significantly.

Typical Pennalloy electrolytes, which by adding these Antioxidants that have been found to be improved include Solutions that deposit the following alloys:

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BATH

Nickel-iron,
Nickel-iron-phosphorus,
Niekel-Eisen-Kobait,
Nickel-iron-copper,
Nickel-iron-cobalt-phosphorus,
Nickel-iron-copper-phosphorus,.
Nlckel-Iron-Copper-Cobalt and
Nickel-Iron-Copper-Cobalt-Phosphorus.

In general, the anion has no effect, and baths can. are formed from chlorides, sulfates, sulfamates or mixtures of these without adversely affecting the effect of the aseorbic or isoascorbic acid. Usually a buffer, such as boric acid, is added to adjust the pH
to stabilize the electrolyte during electrolytic separation. In addition, a primary gloss agent, such as saccharin, and an agent against perforation, such as sodium lauryl sulfate, are used in the electrolysis bath.

In permalloy-type alloy baths, one is used additional sulfur-containing primary gloss agents, such as saccharin, are permitted, since these films are in one environment can be used in which the possibility of corrosive attack is minimal. In addition, the simultaneous deposition leads des to achieve a film with the desired magne table properties required iron already to a material that has very poor corrosion resistance.

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The usable pH range of the Permalloy electrolyte is 1-5, a pH of 2.5 being preferred. The current density used can be 5 to 30 mA / cm, and is preferably 20 mA / cm The temperature of the bath can vary between 15 ° C and 95 ° C and is preferably 25 ° C. Although it is possible to be insoluble Anodes, such as platinum, or anodes made of an alloy thereof Composition how to use the deposition is to use it when practicing the invention, preference is given to using nickel anodes and adding to the iron content of the electrolyte suitable iron-containing compounds to supplement.

Suitable bases include conductors such as copper or alloys containing copper, gold, silver, platinum, and stainless Steel or other metals or non-conductors, such as glass, ceramic Materials, plastics and the like which have been rendered conductive by having a conductive coating on them, e.g. of copper, gold and the like, by processes such as vacuum separation, electroless deposition, Zar dusting, thermal decomposition and the like., Was applied.

The Pennalloy films produced by the process according to the invention are used as logical elements or storage devices gen used in computers.

The following examples illustrate the invention without representing it restrict.

909833/1033 _BAD ORIGINAL

example 1

A Pyrex glass cover plate, which is made conductive became that, on its surface a thin layer of chrome and then a 300 Å thick gold layer was applied by sputtering, degreased by spraying with acetone, then rinsed with water and used as the cathode in the nickel-iron electrolysis bath of the following composition «das Contains water as a solvent, uses:

NiCl ₂ -6H _g O 200 g / l solution FeCl ₂ · 4Η ₂ 0 3 g / l " Η, ΒΟ, 25 g / l " Sodium Saschariii 0.8 g / l " Sodium Lauryl Sulphate 0.4 g / l " NaH ₂ PO ₂ -H ₂ O 0.5 g / l " pH 2.5 temperature 25 ° C Plating time 10 mins anode Nickel sheet Current density 20 mA / cm ² Field strength about 35 oerstet

The deposited Uiekel iron-phosphorus film (at a field strength von 35 Oersted) was largely cracked and did not adhere

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BATH

on the pad. It was not because of this state of the film

possible to measure its magnetic properties.

Example 2

The procedure of Example 1 is repeated with the exception that 5.0 g of 1 isoascorbic acid are added. The nickel-iron-phosphorus film produced is around 20,000 A strong, shiny, firmly adhering and continuous. The magnetic properties were measured with a 60 Cyele Hysteresis Sehlelfen recorder. The coercive force (U _n ) was 0.8 oersted, the anisotropy field strength (H ^) was 2.5 oersted, and the rectangular curve:
Direction about 1.0.

and the rectangle ratio (B „/ B _e ) was ir * the light one

example 3

A Platüe stainless steel [about 2.5 x 7.5 in (1 χ 3 inch)] is anodically g in a solution of 60 Na, POj depending 1 and 30 g NaOH per 1 cleaned. The plate is then rinsed in running water and immersed in a 100% HgSO ^ solution. It is rinsed again with water and checked for surface cleanliness by looking for water interruptions. The plate is then used as a cathode in a solution of the following composition and under the conditions set out below:

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BAD OBIQiNAL

NiSOj, ⁰ 6H _g O 218 g / l solution FeSO ^ 7H ₂ O 4.8 g / l "" H ₅ BO ₃ 25 g / l " Sodium saccharin 0.8 g / l " Sodium aurium sulfate 0.4 g / l » NaH ₂ PO ₂ -H ₂ O 0.5 g / l " pH 2.5 temperature 25 ° C Plating time 10 mins Current density p
20 mA / cm Field strength 35 Oersted anode Nickel sheet

The deposited Ni-Pe-P-FiIm showed clear stress cracks and when attempting to remove the film from the stainless steel base, the film crumbled or crumpled and could not be preserved undamaged.

Example 4

The working cycle of Example 3 is repeated, except that 5.0 g Ascorbic acid 1 can be added to the electrolyte. A 'nickel

Iron-phosphorus film of 20,000 Å thick is produced. The film
is shiny, crack-free, and remains intact when removed from the stainless steel backing. The magnetic

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BATH ORIGINAL

. Properties of the film were measured as in Example 2. the The coercive force (H) was 1.0 oersted, the anisotropy force (H.) was 2.5 oersteds and the Reehteek ratio (BVb) was about 1.0 in the easy direction.

example 5

A copper sheet [x about 2.5? '5> m (1 x 3 inches}] is cathodically per 1 cleaned in a solution of 60 g Trinatrlumphosphat and JQ g of sodium hydroxide. Then, it is rinsed in running water and in a 10 Complete HgSO ^ Solution. It is rinsed again with water and examined in Example J for surface cleanliness, then the copper sheet is used as a cathode in a solution of the following composition and under the following conditions:

Ni ^{f +} (as jSulfamate) Fe ⁺ * (as sulfamates)

H ₃ BO ₃

Sodium lauryJ.su 1 fat NaH ₂ PO ₂ -H ₂ O

pH

temperature

Current density

Plating tent field strength

anode

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2 _S 8 5 g / l ⁰ C 5 S / l η 30th s / i «A / a ² 0, g / l Minutes 0, Oersted 2, 20th 15th 15th 35

The Miekel iron-phosphorus film deposited contained many Hoists and strong tensions.

Example 6 '

The procedure of Example 5 is repeated, but 3.0 g isoascofic acid per liter are added to the electrolyte. A "Hiekel iron-phosphorus film about 20,000 Å thick is produced. The film produced is glossy, free of cracks and adheres well to the substrate. The magnetic properties of the film were measured using a 60 cycle Hysteresis -Schleif en -On zelöhHungsgerät and gave the following values:

Coercive force (H Is 1., 8 Oersted

«3

Anisotropiefeidstärke (H ^): 3.1 ^M Rechtsckverhäitnis cb_ / ^B _S) x about 1.0 (in the direction of light)

In Examples 1 through 6, the ratio of nickel to iron in the deposit is nominally 80 ϊ 2C (or 4: 1} and the phorgehaXt is about 1 wt »- # of the entire film»

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at JM ⁺⁴ Fe ⁺⁺ Co * g / 1 NaH ₉ FO ₅ , * 2 • - Antioxy * - Time pH current ^Η Λ
g / 1 N / A- N / A- Results . ■ ~ game g / 1 g / 1 g / 1 £ CL g / 1 0.5 dans Minu density trium trium g / 1
(I) - 180- th saceha- lauryl ascorbic - rin suIfat 0.5 acid - g / 1 g / 1 tm (A) - As- - corbin- 5 (1) 0.5 eKure 5 (1) 25th «A - - 3 (A) 85 cracked, 7th 48 1.44 - 0.5 3 (A) 10 2 * 5 20th 25th 0.8 0.4 easy
adherent 8th 48 1.44 H* <■ · ma 3 (1) 10 2.3 20th 0.8 0.4 , R-NH cracked, co 9 48 1.44 3 0.5 3 (1) 10 2.5 20th 85 0.8 0.4 easy (O M. - 5 (A) 30th adherent OO
CaJ 10 48 1.44 3 0.5 0.5 5 (A) 10 2.5 20th 0.8 0.4 R-NH cracked, CO 11 60 1.7 m - 10 2.0 20th 30th 0.8 0.4 easy ' 1 * "* 0.5 0.5 30th adherent I.
Λ O 12th 60 1.7 0.5 - 10 2.0 20th 30th 0.8 0.4 R-NH 9 u> 13th 113 2.82 3 0.5 0.5 15th 2.8 15th 25th - 0.4 NR-H 14th 113 2.82 3 15th 2.8 "15 25th - 0.4 R-NH 15th 48 1.44 - - 10 2.5 20th 25th 0.8 0.4 NR-PH 16 48 1.44 - 10 2.3 20th 25th 0.8 0.4 NR-PH 17th 48 1.44 3 - 10 2.5 20th 30th 0.8 0.4 NR-PH 18th 48 1.44 3 0.5 10 2.5 20th 30th 0.8 0.4 NR-FH 19th 60 1.7 - 0.5 10 2.0 20th 30th 0.8 0.4 NR-FH 20th 60 1.7 - 0.5 10 2.0 20th 30th 0.8 0.4 NR-PH CiD 21 113 2.82 3 0.5 15th 2.8 15th _ 0.4 NR-PH cn
OC 22nd 113 2.82 3 15th 2.8 15th 0 * 4 NR-PH

R-NH (cracked, non-adhesive) NR-H (not adhering to cracks) NR-FH (not adhering to cracks firmly)

OC

14968A3

- · 20 -

In Examples 7-22, the nickel to iron ratio of the deposited film is nominally 80:20 (or 4: 1); · The phosphorus content is about 1 weight? Total film if phosphorus is present? the cobalt content is about 6 wt -.% of the total film when cobalt present ISTJ and the copper content is about 7.5 wt -.% of Gesamtfiitms when copper is present.

It has been shown that it was previously difficult to be reproducible To deposit Permalloy-Schiohteri, which do not goat by themselves, come off or peel off “By using the antioxidants. Ascorbic Acid or Isoascorbic Acid, It Is Now Possible Pennalloyfilmo by electrodeposition without deterioration of the properties establish by the stresses that tearing, peeling or spontaneous peeling of the film are eliminated. Another benefit of the Use of the antioxidants is to achieve a per » malloyfilms that adheres firmly and is made in sufficient thickness can become self-supporting when removed from a peelable backing.

The embodiment of the present invention, according to which a « shiny nickel deposit is obtained, is now based on egg?. · Watts-Bads.

A typical Watts electrolyte includes *: - «.» «« "ΟAgende Lösurg:

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BATH

NiSO ^ 6Η ₂ 0 500 g / l bath conditions

NlCl ₂ -6H ₂ O ^ 5 g / 1 ρΗί 3.5

• Η, ΒΟ, 4θ g / l temperature: 65 ° C

Wetting agent (sodium current density: 43 mA / om ²

lauryl sulfate} 0.4 g / l (40 asf)

Thickness: about 0.025 now (0.001 ")

(about 30 minutes)

A quantity of 1 g / l to saturation is added to this bath, with 5 g / l being preferred, isoasoorbic acid or ascorbic acid (the former is an isomer of vitamin Cl. A suitable secondary brightener is used in conjunction with the primary brightener in the standard Watts bath used tests such samples of deposited nickel showed © into substantial reduction of metal corrosion such samples compared to samples _a receiving from baths using sulphurous primary scraps were. It was found that coumarin and 2-Butin-1 "4 -diol are leveling agents that act synergistically with isaseorbic acid and ascorbic acid. For the selected bath listed above, we found an amount of O ₅ I to 2.5 g of 2-butyne-1,4-diol per 1, preferably 0.35 g / l or 4 mmol / l, a shiny, corrosion-resistant nickel deposit, pure coumarin an amount of 0.1 to 4 g / l, preferably O ₃ S g / l, is used in the bath As has been found, the classes of acetylene! - See Alcohols and Coumarins Synergistic with Isoascorbic Acid

909833/1033 Bad qriq, _Nal

and ascorbic acid together. Examples of such typical alcohol compounds are given in Table X of US Pat. No. 2,002. Typical coumarin compounds are coumarin, hydroxycoumarins, homoeumarins and chlorocoumarins >

In summary, it can be said that in the field of electrodeposition of nickel or nickel alloys, there is a need for shiny nickel deposits that are corrosion-resistant and relatively cheap to obtain. duration. So far, only nickel deposits have been corrosion-resistant if no primary brighteners were used in the bath. Since all previously known primary glossing agents contain sulfur, the lack of the primary glossing agent increases the corrosion resistance of the deposited nickel. However, it must then SekundärgläEzbildner to favor the leveling used wes-desi, but this benefit 1st uer Einebming because of the dens added SekundärglaKzbildr he "own spamiuiigsergeugender _Ä limited characteristics. The Eßdppodukt then kcrroaiosisb Although ^ stän'digj has jedooh varhältnisinässi.g bad Einebnuag and possesses usual place h Chip nmgen to increase in attempts the leveling and gloss of this Abscheidunge ^ form rapidly residual voltages up to a very · high degree, and the abs tend to peel, crack, and peel off, and show very limited bukti-

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EaO OBIGlNAL

lity. By using isoascorbic acid or ascorbic acid is now obtained shiny, corrosion-resistant, flat, stress-free Nickelabseheidungen because Isoasoorbinsäure and ascorbic acid behave in some ways like the usual primary brighteners, but no sulfur s thaiten. A class of primary brighteners has thus been found which act synergistically with most secondary brighteners and lead to highly corrosion-resistant nickel peeling off. Another advantageous feature of the invention is that much more leveled semi-gloss Niekelabseidüngen are available. The latter are available because the new primary brighteners, namely isoascorbic acid and ascorbic acid, when added to the usual semi-gloss baths, allow the presence of higher concentrations of secondary brighteners without impairing the ductility or increasing the residual stresses of the deposited nickel.

In addition, ascorbic acid and isoascorbic acid act as antioxidants in the deposition of magnetic films of a Niclcel-iron alloy electrolytes used; these acids cause a retardation and reversal of the oxidation of the ferrous ions to Perriioiie »and thus an improvement in the nature of the educated Magnetic film as well as an extension of the useful life of the electrolyte.

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Claims (10)

Claims 1. Bath for the electrodeposition of nickel and nickel alloys in the form of an aqueous acidic solution, characterized by a content of ascorbic acid and / or isoascorbic acid as an additive. 2. Bath according to claim 1, characterized in that the The additive is present in an amount corresponding to a molar ratio of additive to nickel in the range of from 0.003 to 0.034 is equivalent to. 3. Bath according to claim T or 2, characterized in that it also contains a leveling agent containing an acetylenic alcohol or a coumarin compound. 4. Bath according to Anspnjch 3, characterized in that it Contains tsoacorbic acid and an ethylenic alcohol. 5. Bath according to one of claims ι to 4, characterized in that it also contains 0.1 to 4 g of coumarin or 0.1 to 2.5 g Contains 2-3utin-1,4-diol per liter. 909833/10 33 BATH ORIGINAL 6. Bath according to claim 1, characterized in that it is used for the deposition of a nickel-iron alloy nickel ions, Elsenions and the additive in an amount of 1 to. Contains 5 g / l solution. 7. Bath according to claim 6, characterized in that it per liter 48 to 115 g Ni ⁺ * 1.44 to 2.82 g Fe ⁺⁺ and 1. up to 5 g ascorbic acid or Isoascorbic acid contains. 8. Bath according to claim 7, characterized in that it also per liter Cu ⁺ * in an amount up to 0.5 g and / or r amount up to 3 g and / or in an amount up to 0.5 g Co ⁺ * in an amount up to 3 g and / or contains. 9. A method for electrodeposition of nickel-iron alloys in a bath according to one of claims 1 to 8, characterized in that the electrodeposition is carried out at 25 ° C for 10 minutes at a current density of 20 mA / cm ² and a field strength of 35 Oersted using a sheet nickel anode. 909833/1033 φ
* i ORIGINAL BATHROOM 10. A method for the electrodeposition of a nickel layer in a bath according to any one of claims 1 to 8, characterized in that the electrodeposition is carried out at 65 ° C for 30 minutes at a current density of 43 mA / cm performs. 909833/103 3 BATH