US2658867A - Electrodeposition of nickel - Google Patents

Description

Patented Nov. 10,

Harsh .W Chemical Company, Cleveland, @Qhio',

cor iora'tioniof o m mowing, Application March 6, 1952, Serial No. 275,220

is meat.

This invention relates to v eleg:trodeposition v of bright ,nickel by the use of a single brightenin s ticn nt 9 th bis-.p iqinmm FY9319? mixture of equivalent addition agents of the same y is t l...

t h ,i r s et in n i n. it ha v ber posed to use compounds of the aboveiclassas brighteners in connection with auxiliary brighteners for acid nickel plating from a -Watt's-type of solution. The maximum concentration, however, was thought to be about five o'ne-hundredths of a gram per liter ('five thousandths being considered hatter) inasmuch as greater amounts were found to embrittle the deposit, and the auxiliary brightener was thoughtjessential. I

I have now-disco'veredthat by using comparatively large concentrations of such addition agents as the sole brightener an acid nickel plating solution I am able to produce deposits which are indeed brittle, but the brittleness-of whichis of a surprising and for many purposes unobj ectionable type. When I first eiramined these deposits, which because they build brightness so rapidly may be called q'iiick bright nickel, I thought them to be ductile without the usual aromatic sulfonat'e or sulf onarnid; They do not produce the characteristic fcry? -of the usual type of brittle deposits upon sharp bending-n01 iS there evidence of cracking visible to the naked eye. These deposits, as indicated, have the property of building brightness at -a remarkably fast rate, v so that relatively thin "deposits on unbuiied or mattesur faces exhibit extreme brilliance; and they are characterized byeXc'ellent smoothing andscr'atch filling. On the otherhand, microscopic-examinae tion indicates that these "dfipos'its ar *full of fine hair-line cracks not discernible 'by-the naked eye. Adherence to steel is not good, but a 0.00017 :to 020002". copper deposit on steel prior to fquic k bright nickel prdti'des satisfactoryadherence Adherence to brass, copper and gray nickname trodeposits is satisfactory. c

Poor adherenceand visiblecracking of the deposit, whichcan be produced by too :high concentrations of addition agent, arerelated not only to such concentration but also to the thickness of the deposit, For thin flash coatings for quick brightness building a high conc ntration ofaddition agentmaybe used. For thickerdepositsjto avoid stress cracking, lower cbncenaa icas'are superior, Tests indicate t1'iat the-appearance "of the deposit is not'alterd arte'r proi' geguse-or the "solution. Ga rb'on treatment =6: the semi-1pc after long use produces ftl ie br'dinary grayaii eke lsolution. "The deposit'eitliibit's mieraseopittracrs at the start and, as far s has been determined, retains thisjproperty indefinitely.

In salt spray corrosion comparisons with 'a commercial bright nickel deposit it was found that in the case of thin dep'osits (0.0001" to 0.0002") directly on steel the commercial deposit was much superior to the quick bright deposits of the same thickness. On copper deposits (0.4 to 0-,8,m n st e ther wasn an re iable di t nc exc pt tha le s gre .discq q at sm e d w th the zcommercia n ck In a ll ie above cases the quick bright nickel is much br hie la d m qt ha h comm rcia T a s-h icke riep s'it .;A Qit e c rms ion an s w r s ren im ac test w t iro' weight, and in most-cases it was round that nickel deposits according to the invention were superior to the commercial f bright nickel around t mpa ;acre:. i -v l.

C ns d r t ef ifl lt of la in bra s and particularly {copper directly with chromium, it

would appear commercially desirable to use the novel deposits ,as la flash coating on copper or brass prior tochrome plating. A flash coating i h qqra n lai idie s n gives n 1 cellent appearing finish. Heavier thicknessesmay be O apt c a rams u he es -hfi ries obtainable in thin coatings would ,appear to be 0f mo e mercia1 inte est hin-coatings c the novel bright nickel over gray or semi-bright nickel have the advantage of improving thelustre although without improving the resistance to corrosion. I

It is ph iqu th 'ith ishtnick l cc ain tqqtne nt on can be us d effe t e u de lci i stances wh re xt eme bri htnss is desi e 1- pecia l Wh r it i des r d .t l lii d. v11 s,1, tnJ ss quic l t is m nis th eastpo vsihle .gq'u ti r f ck l: iASi H l LKnQ h+flldbri t QPQQ i .ln i k l y as brigh as com rc bright nickelz It'does, "however, m a ry excellent surface qnlwhichtp epos n cke mat qc rd n t err g i in Emma, the icke dep i lti t 1 1 lbr elitngS when ittle a /mes pr v des a lamin tedg a g od c os n r is a c. are adhs' ,7 is brilliant n'ckel color (due *to 'brighteninjg Smoothing c lnwh'ile(b in econ deposits according to the present inve H 59 s arc ed v'srrrarnicke,snares l. inl sl' froni "the '-Watts bath, or over senii=bright 'riickel' nickel such as obtained from a Watts bath modified by the addition of coumarin. Still other applications of the invention may be found feasible and advantageous.

The preferred basic solutions in connection with which the invention is realized are as follows:

TABLE I All sulfate NiS .7H O 100 to 400, preferably 200 to 300 grams Boric acid 0 to 60, preferably 10.to 40 grams H 0 to make 1000 cc.

High chloride NiSO4.6H20 7 to 225, preferably 190 to 200 grams NiCl fiH O 50 to 150, preferably 70 to 1o0 grams Boric acid O to 60, preferably to 40 grams H20 to make 1000 cc.

Sulfate-chloride (Watts type) N,N'- (oxydibutyl) -bis-pyridinium chloride N,N- (oxydibutyl) -bis-isoquinolinium chloride N,N'- (2-butenylene) -bispyridinium bromide N,N- (Z-butenylene) bis-isoquinolinium bromide The last compound has the following structure:

QC RGHFQ QECHHGQ3 The bromides and chlorides are fully equivalent to each other. No anti-pit agent is used, since no substantial pitting occurs.

These compounds are maintained in the acid nickel plating solution, preferably those above described, in concentration from 0.1 to 1.0 gram per liter, preferably from 0.2 to 0.75 gram per liter.

'NiS0 ..7H '0 100 to 400, preferably 200 to 300 grams NiCl .6H O 10 to 60, preferably 25 to 40 grams Boric acid 0 to 50, preferably 15 to 40 grams H 0 to make 1000 cc.

To each of the foregoing basic solutions I add one or a mixture of compounds of the formula:

shown by several examples in Table II below) containing in the aggregate for both pyridinium groups from 1 to 10 carbon atoms, the extra valences of the carbon atoms of A being satisfied by hydrogen and from 0 to 1 hydrocarbon groups containing in the aggregate from 1 to 6 carbon atoms, and where each hydrocarbon substituent group is attached to from 1 to 2 atoms of the group carrying such substituent group.

The following compounds are specific examples of the groups of addition agents above referred to, the same being utilized according to the invention in acid nickel plating solutions, preferably nickel sulfate and mixed nickel sulfate and nickel chloride solutions, suitably the basic solutions above set forth.

TABLE II N,N'-oxydiethylene pyridinium isoquinolinium chloride g 7 Propanone-l,3-bis-pyridinium chloride N,N '-oxydipropylene-bis-pyridinium perchlorate The following specific example will serve to illustrate the invention:

EXAMPLE I A solution was made up containing:

Grams NiSO4.6H2O 240 NiClzfiHzO 40 H2303 40 N,N-ethylene-bis-pyridinium bromide 0.4 H20 to make one liter.

This solution was operated at a pH of 3.5, a temperature of F. and a cathode current density of 40 amperes per square foot. On a matte copper surface produced by electrodepositing copper on steel, extreme brilliance was achieved at a thickness of 0.000065 of an inch. On bright copper produced by electrodeposition from a commercial ,bright copper solution, extreme brilliance was achieved at a thickness of 0.00003 of an inch. On a vapor blasted steel panel having a roughness of RMS 34.5, quick bright nickel was deposited to a thickness of 0.000? of an inch. The deposit exhibited an RMS of 6.6 and was fully bright.

On the bright copper above referred to, increasing the concentration of the addition agent to 0.75 gram per liter resulted in securing extreme brilliance at a thickness of 0000015 of an inch, while decreasing it to 0.1 gram per liter resulted in securing extreme brilliance at 0.0005 of an inch.

. Having thus described the invention, what is claimed is: l

1. A nickel plating solution comprising an aqueous, acid solution of nickel material supplying nickel ions and an addition agent dissolved in said solution and capable of imparting to electrodepositsproduced therein improved rates of increasing brightness with respect to increasing thickness of deposit, said solution consisting essentially of a composition from the class consisting of. aqueous solutions of nickel sulfate and aqueous solutions of nickel sulfate and nickel chloride and said addition agentbeing atleast one bis-pyridiniumcompound of the formula,

where A is achain made up of from 1 to 10 carbon atoms and from 0 to 2oxygen atom and the free valences are satisfied by hydrogen and from 0 to 4 hydrocarbon groups containing in the aggregate for both pyridinium groups from 1 to 10 carbon atoms, the extrarvalencesof the carbon atoms of A being satisfied by hydrogen and from 0 to 1 hydrocarbon groups containing in the aggregate carbon substituent group is attached to from 1 to 2 atoms of the group carrying such substituent roup, said addition agent being present in solution to the extent of from 0.1 to 1.0 gram per liter.

2. The invention as defined in claim 1 wherein the concentration of said addition agent is from 0.2 to 0.75 gram per liter.

3. The invention as defined in claim 1 wherein the addition agent is N ,N'-ethylene-bis-pyridinium bromide.

4. The invention as defined in claim 1 wherein the addition agent is N,N-trimethylene-bispyridinium bromide.

5. The invention as defined in claim 1 wherein the addition agent is N,N-tetramethylenebispyridinium bromide.

6. The invention as defined in claim 1 wherein the addition agent is N,N'-pentamethylene-bispyridinium bromide.

'7. The invention as defined in claim 1 wherein the addition agent is N,N'-methylene-bis-pyridinium bromide.

8. A nickel plating solution comprising an aqueous, acid solution of nickel material supplying nickel ions andan addition agent dissolved in said solution and capable of imparting to electrodeposits produced therein high rates of increasing brightness with respect to increasing thickness of deposit, said solution consisting essentially of nickel sulfate equivalent to from 100 to 400 grams of nickel sulfate heptahydrate per liter, nickel chloride equivalent to from 10 to 60 grams of nickel chloride hexahydrate per liter, boric acid up to 50 grams per liter, and said addition agent being selected from the class consisting of N,N-ethylene-bis-pyridinium bromide, N,N' trimethylene bis pyridinium bromide, N,N' tetramethylene-bis-pyridinium bromide, N,N'-pentamethylene-bis-pyridinium bromide, N,N' decamethylene bis-pyridinium bromide, N,N'-methylene-bis-pyridinium bromide, N,N'-

oxydimethylene-bis-pyridinlum chloride, N,N'- oxyethylenemethylene-bis-pyridinium chloride, N,N' oxydiethylene bis pyridinium chloride, N,N'-oxyditrimethylene-bis-pyridinium chloride, N,N methylene bis isoquinolinium chloride, N,N oxydimethylene-bis-isoquinolinium chloride, N ,N'-oxyethylenemethylene-bis-isoquinolinium chloride, N,N-oxydiethylene-bis-isoquinolinium chloride, N,N'-oxymethylene pyridinium chloride, ethylene isoquinolinium chloride, N,N'- oxydiethylene pyridinium isoquinolinium chloride, propanone 1,3 bis-pyridinium chloride, N ,N-oxydipropylene-bis-pyridinium perchlorate, N ,N'- (oxydibutyl) -bis-pyridinium chloride, N,N'- (oxydibutyl)-bis-isoquinolinium chloride, N,N'- (2-butenylene-bispyridinium bromide, N,N'-(2- butenylene)-bis-isoquinolinium bromide, said addition agent being present to the extent of from 0.2 to 0.75 gram per liter.

9. The invention defined in claim 8 wherein said addition agent is N,N'-ethylene-bis-pyridinium bromide.

10. The invention defined in claim 8 wherein said addition agent is N,N-trimethylenebispyridinium bromide.

11. The invention defined in claim 8 wherein said addition agent is N,N'-tetramethylene-bispyridinium bromide.

'12. The invention defined in claim 8 wherein- References Cited in the file of this patent UNITED STATES PATENTS Name Date Brown July 4, 1950 Brown -a Apr. 24, 1951 Number

Claims (1)

1. A NICKEL PLATING SOLUTION COMPRISING AN AQUEOUS, ACID SOLUTION OF NICKEL MATERAL SUPPLYING NICKEL IONS AND AN ADDITION AGENT DISSOLVED IN SAID SOLUTION AND CAPABLE OF IMPARTING TO ELECTRODEPOSITS PRODUCED THEREIN IMPROVED RATES OF INCREASING BRIGHTNESS WITH RESPECT TO INCREASING THICKNESS OF DEPOSIT, SAID SOLUTION CONSISTING ESSENTIALLY OF A COMPOSITION FROM THE CLASS CONSITING OF AQUEOUS SOLUTIONS OF NICKEL SULFATE AND AQUEOUS SOLUTIONS OF NICKEL SULFATE AND NICKEL CHLORIDE AND SAID ADDITION AGENT BEING AT LEAST ONE BIS-PYRIDINIUM COMPOUND OF THE FORMULA