U.S. patent application number 14/159153 was filed with the patent office on 2014-05-15 for treatment of plastic surfaces after etching in nitric acid containing media.
This patent application is currently assigned to MacDermid Acumen, Inc.. The applicant listed for this patent is MacDermid Acumen, Inc.. Invention is credited to Roshan V. Chapaneri, Roderick D. Herdman, Trevor Pearson, Anthony Wall.
Application Number | 20140134338 14/159153 |
Document ID | / |
Family ID | 47992821 |
Filed Date | 2014-05-15 |
United States Patent
Application |
20140134338 |
Kind Code |
A1 |
Chapaneri; Roshan V. ; et
al. |
May 15, 2014 |
Treatment of Plastic Surfaces After Etching in Nitric Acid
Containing Media
Abstract
A process for plating metal on plastic substrates, particularly
ABS substrates, without the use of chrome containing etchants is
disclosed. The process involves (i) etching the plastic substrate
in an acidic solution of nitrate ions, and preferably silver ions,
(ii) conditioning the substrate in an aqueous solution containing
an amine or ammonia, (iii) activating the substrate, preferably
with a palladium activator, and (iv) plating the substrate with an
electroless plating solution. The process allows for complete
adherent electroless plating of plastic substrates, particularly
ABS substrates, without the use of chromic etchants.
Inventors: |
Chapaneri; Roshan V.;
(Foleshill Coventry, GB) ; Wall; Anthony; (Oldbury
West Midlands, GB) ; Pearson; Trevor; (Cradley Heath
West Midlands, GB) ; Herdman; Roderick D.;
(Staffordshire, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MacDermid Acumen, Inc. |
Waterbury |
CT |
US |
|
|
Assignee: |
MacDermid Acumen, Inc.
Waterbury
CT
|
Family ID: |
47992821 |
Appl. No.: |
14/159153 |
Filed: |
January 20, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13248550 |
Sep 29, 2011 |
|
|
|
14159153 |
|
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Current U.S.
Class: |
427/305 |
Current CPC
Class: |
C23C 22/73 20130101;
C23C 18/30 20130101; C23C 18/24 20130101; C23C 18/32 20130101; C23C
18/2086 20130101 |
Class at
Publication: |
427/305 |
International
Class: |
C23C 22/73 20060101
C23C022/73 |
Claims
1. A method of treating a plastic substrate to accept electroless
plating thereon, the method comprising the steps of: a) etching a
surface of the plastic substrate by contacting the plastic
substrate with an acidic solution containing nitrate ions; b)
contacting the etched plastic substrate with a conditioning
solution comprising an aqueous solution comprising a quaternary
amine; c) activating the plastic substrate; and d) contacting the
activated plastic substrate with an electroless metal plating
solution to deposit metal thereon.
2. The method according to claim 1, wherein the acidic solution
comprises oxidizing metal ions, wherein the oxidizing metal ions
are selected from the group consisting of silver, manganese,
cobalt, cerium and combinations thereof.
3. The method according to claim 2, wherein the acidic solution
comprises silver nitrate and nitric acid.
4. The method according to claim 3, wherein the acidic solution
comprises a wetting agent.
5. The method according to claim 1, comprising the step of
immersing the plastic substrate into an acid rinse after step (b)
and before step (c).
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. (canceled)
11. (canceled)
12. (canceled)
13. (canceled)
14. The method according to claim 1, wherein the quaternary amine
comprises a polymeric quaternary amine having the general formula:
##STR00002## wherein: R.sup.1, R.sup.2, R.sup.3 and R.sup.4
independently can be the same or different and may be selected from
--CH.sub.3, --CH.sub.2CH.sub.3, --CH(CH.sub.3).sub.2 or
--CH.sub.2CH.sub.2OH; R.sup.5 is --CH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2CH.sub.2--, --CH.sub.2CH.sub.2CH.sub.2CH.sub.2--,
--CH.sub.2CHOHCH.sub.2-- or --CH.sub.2CH.sub.2OCH.sub.2CH.sub.2; X
and Y can be the same or different and are selected from Cl, Br,
and I; v and u can be the same or different and each can be 1 to 7;
and n is 2 to about 200.
15. The method according to claim 14, wherein in the polymeric
quaternary amine, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each
CH.sub.3; R.sup.5 is --CH.sub.2CH.sub.2OCH.sub.2CH.sub.2; v and u
are 3; X and Y are Cl; and n is an average of about 6.
16. The method according to claim 1 wherein the concentration of
the amine and/or the ammonia in the conditioning solution is
between about 5 and about 100 g/L.
17. The method according to claim 16, wherein the concentration of
the amine in the conditioning solution is between about 10 and
about 50 g/L.
18. The method according to claim 1, wherein the conditioning
solution has a pH of between about 0 to about 14.
19. The method according to claim 18, wherein the conditioning
solution has a pH of between about 6 and about 12.
20. The method according to claim 1, wherein the step of activating
the etched and conditioned plastic substrate comprises contacting
the plastic substrate with an activation solution comprising
palladium.
21. The method according to claim 1, further comprising the step of
contacting the activated plastic substrate with an acid treatment
prior to step (d).
22. The method according to claim 1, wherein the electroless metal
plating solution comprises electroless nickel.
23. The method according to claim 1, wherein the plastic substrate
comprises an acrylonitrile/butadiene/styrene copolymer or an
acrylonitrile/butadiene/styrene copolymer blended with
polycarbonate.
24. The method according to claim 2, wherein the oxidizing metal
ions are produced by electrochemical oxidation.
25. The method according to claim 24, wherein the oxidizing metal
ions comprise Ag.sup.2+.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to the treatment of
plastic surfaces following etching in an acidic solution containing
nitrate ions.
BACKGROUND OF THE INVENTION
[0002] For many years, processes have been available to facilitate
the deposition of electrodeposited metals onto plastic substrates.
A typical process involves the steps of: [0003] (1) etching the
plastic in a suitable etching solution such that the surface of the
plastic becomes roughened and wetted so that the subsequently
applied deposit has good adhesion; [0004] (2) activating the
surface of the plastic using a colloidal or ionic solution of a
metal capable of initiating the deposition of an autocatalytically
applied metal coating of typically copper or nickel; [0005] (3)
depositing a thin layer of autocatalytically applied metal; and
[0006] (4) carrying out electrodeposition of metal onto the
metallized plastic substrate. Typically, layers of copper, nickel
and/or chromium are applied to produce the final article.
[0007] The most widely used plastic substrates include
acrylonitrile/butadiene/styrene copolymers (ABS) or ABS blended
with polycarbonate (ABS/PC). These materials are readily formed
into components by the process of injection molding. ABS comprises
a relatively hard matrix of acrylonitrile/styrene copolymer and the
butadiene polymerizes to form a separate phase. It is this softer
phase of polybutadiene (which contains double bonds in the polymer
backbone) which can be readily etched using various techniques.
[0008] Traditionally, the etching has been carried out using a
mixture of chromic and sulfuric acids which must be operated at an
elevated temperature. The chromic acid is capable of dissolving the
polybutadiene phase of the ABS by oxidation of the double bonds in
the backbone of the polybutadiene polymer, and this has proven to
be reliable and effective over a wide range of ABS and ABS/PC
plastics. However, the use of chromic acid is becoming increasingly
regulated because of its toxicity and carcinogenic nature. For this
reason, there has been a considerable amount of research into other
means of etching ABS and ABS/PC plastics.
[0009] There are a number of approaches possible in order to
attempt to achieve this. For example, acidic permanganate is
capable of oxidizing the double bonds in the polybutadiene. Chain
scission can then be achieved by further oxidation with periodate
ions. Ozone is also capable of oxidizing polybutadiene and this
approach has also been attempted. However, ozone is extremely
dangerous to use and is also highly toxic. Likewise, sulfur
trioxide can be successfully utilized to etch ABS, but this cannot
be successfully achieved on a typical plating line. Other examples
of prior art techniques for etching ABS plastics without the use of
chromic acid can be found in U.S. Pat. Pub. No. 2005/0199587 to
Bengston, U.S. Pat. Pub. No. 2009/0092757 to Sakou and U.S. Pat.
No. 5,160,600 to Gordhanbai, the subject matter of each of which is
herein incorporated by reference in its entirety. However, none of
these methods have achieved widespread commercial acceptance.
[0010] Thus, there remains a need in the art for an improved
process of etching plastics without chromic acid, while continuing
to utilize a conventional activation process containing a palladium
colloid followed by electroless nickel.
SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to provide a
process for etching plastics without the use of chromic acid.
[0012] It is another object of the present invention to provide a
process for etching acrylonitrile/butadiene/styrene copolymers
without the use of chromic acid.
[0013] It is still another object of the present invention to
provide an improved conditioning treatment for conditioning the
surfaces of an etched plastic.
[0014] To that end, the present invention relates generally to a
method of treating a plastic substrate to accept electroless
plating thereon, the method comprising the steps of: [0015] a)
etching at least a surface of the plastic substrate by contacting
the plastic substrate with an acidic solution containing nitrate
ions; [0016] b) contacting the etched plastic substrate with a
conditioning solution comprising an aqueous solution comprising
ammonia, an amine or combinations thereof; [0017] c) activating the
etched and conditioned plastic substrate; and [0018] d) immersing
the activated plastic substrate into an electroless metal plating
solution to deposit metal thereon.
BRIEF DESCRIPTION OF THE FIGURES
[0019] FIG. 1 depicts an infra-red analysis obtained from untreated
ABS.
[0020] FIGS. 2A and 2B depict an infra-red analysis obtained from
ABS treated with a chromic acid/sulfuric acid etch solution of the
prior art.
[0021] FIGS. 3A and 3B depict an infra-red analysis obtained from
ABS treated with an acidic solution of nitrate and silver ions.
[0022] FIGS. 4A and 4B depict an infra-red analysis obtained from
ABS treated with an acidic solution of nitrate and silver ions and
then post-treated in an ammonia solution.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] In preliminary experiments using nitric acid/silver(II) etch
compositions, the inventors of the present invention discovered
that although this etch composition can be used to effectively etch
an ABS or ABS/PC plastic to give an excellent surface topography,
the subsequent catalysis of the surface could not be achieved and
there was no deposition of nickel when the components were
subsequently immersed in the electroless nickel plating process.
Examination of the surface of the plastic using infrared
spectroscopy indicates that the surface of the plastic has been
chemically altered to some degree. New peaks were found following
the etching stage, which almost disappeared when the plastic was
immersed in hot water (80.degree. C.) for 10 minutes. However, even
though the surface of the plastic had apparently reverted in
composition to something similar to its original composition,
palladium adsorption and subsequent catalyzation of the surface
could not be achieved.
[0024] Surprisingly, the inventors of the present invention have
discovered that immersing the etched plastic in a solution
containing amines can condition the surface so that palladium
adsorption can be achieved. Without wishing to be bound by theory,
the inventors consider that it is possible that the amines are
adsorbed onto the surface of the etched plastic, thus imparting a
positive charge on the surface of the plastic when immersed into
the acidic palladium colloid solution. With primary, secondary and
tertiary amines, this positive charge is most likely formed by
protonation of the amines, and with quaternary amines, the positive
charge is already present on the amine.
[0025] The inventors have also found, through infrared
spectroscopy, that an etched plastic can be modified with an
amine-based post treatment. In addition to the disappearance of the
peaks introduced following the etching stage, a new functional
group appears to have been introduced. The composition of the
invention conditions the surface of the plastic so that effective
palladium adsorption can be achieved in order to catalyze the
subsequent deposition of autocatalytic metal deposits.
[0026] According to the present invention, a method is provided for
the catalysis and subsequent metallization of plastics which have
been etched in nitric acid containing solutions. In a preferred
embodiment, the method of the invention comprises the following
steps: [0027] a) etching at least a surface of the plastic
substrate by contacting the plastic substrate with an acidic
solution containing nitrate ions; [0028] b) contacting the etched
plastic substrate with a conditioning solution comprising an
aqueous solution comprising ammonia, an amine or combinations
thereof; [0029] c) activating the etched and conditioned plastic
substrate; and [0030] d) immersing the activated plastic substrate
into an electroless metal plating solution to deposit metal
thereon. Following the above steps, the metallized component can be
electroplated in the usual manner.
[0031] The acidic etching solution preferably comprises nitric
acid. In addition, other mineral acids such as sulfuric acid may
also be added to the composition. In a preferred embodiment the
acidic etching solution also contains oxidizing metallic ions of
metals including, for example, silver, manganese, cobalt, cerium
and combinations thereof, preferably in their highest oxidation
state. Preferably, these ions are produced by a process of
electrochemical oxidation. In addition, if desired, a wetting agent
may also be added to the acidic etching solution. One suitable
wetting agent is available from MacDermid, Inc. under the trade
name Macuplex STR.
[0032] Thereafter, the etched plastic substrate is contacted with
the conditioning solution. In one preferred embodiment the etched
plastic substrate is immersed in the conditioning solution. The
concentration of amines or ammonia in the aqueous conditioning
solution is not critical but is preferably within the range of
about 5 to about 100 g/L, more preferably in the range of about 10
to about 50 g/L. The pH of the solution may be from 0 to 14, but is
preferably in the range of 6-12.
[0033] As discussed above, the amine may be a primary, secondary,
tertiary or quarternary amine. In the alternative, the solution may
comprise ammonia instead of the amine. In addition, it is also
possible to use a combination of different amines or a combination
of an amine with ammonia in the conditioning solution of the
invention.
[0034] Suitable primary amines include, for example,
monoethylamine, mono-n-propylamine, iso-propylamine,
mono-n-butylamine, iso-butylamine, monoethanolamine,
neopentanolamine, 2-aminopropanol, 3-aminopropanol,
2-hydroxy-2'(aminopropoxy)ethylether, 1-aminopropanol,
monoisopropanolamine, diethylaminopropylamine, aminoethyl
ethanolamine and combinations of the foregoing. In a preferred
embodiment, the primary amine comprises monoisopropanolamine or
diethylenetriamine.
[0035] Suitable secondary amines include, for example,
diethylamine, dibutylamine, diethanolamine, methylethylamine,
di-n-propanolamine, di-iso-propanolamine, N-methylethanolamine,
N-ethyl ethanolamine, N-methyl ethanolamine, di-isopropanolamine,
diethylenetriamine, triethylenetetramine, tetraethylenepentamine
and combinations of the foregoing. In a preferred embodiment, the
secondary amine comprises di-ethanolamine or
diethylenetriamine.
[0036] Suitable tertiary amines include, for example,
N,N-dimethylethanolamine, triethylamine, trimethylamine,
triisopropylamine, methyldiethanolamine, triethanolamine, and
combinations of one or more of the foregoing. In a preferred
embodiment, the tertiary amine comprises N,N-dimethyl
ethanolamine.
[0037] Quarternary amines are also generally suitable, including
quarternary (poly) amines. Suitable quarternary amines also include
polymeric quarternary amines having the general formula:
##STR00001##
[0038] Wherein:
[0039] R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently can be
the same or different and may be selected from --CH.sub.3,
--CH.sub.2CH.sub.3, --CH(CH.sub.3).sub.2 or
--CH.sub.2CH.sub.2OH;
[0040] R.sup.5 is --CH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2CH.sub.2--, --CH.sub.2CH.sub.2CH.sub.2CH.sub.2--,
--CH.sub.2CHOHCH.sub.2-- or
--CH.sub.2CH.sub.2OCH.sub.2CH.sub.2;
[0041] X and Y can be the same or different and are selected from
Cl, Br, and I;
[0042] v and u can be the same or different and each can be 1 to 7;
and
[0043] n is 2 to about 200.
[0044] In one embodiment the polymeric quaternary amine is
Mirapol.TM. WT (available from Rhodia) in which in the above
formula:
[0045] R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each CH.sub.3;
[0046] R.sup.5 is --CH.sub.2CH.sub.2OCH.sub.2CH.sub.2;
[0047] v and u are 3;
[0048] X and Y are Cl; and
[0049] n is an average of about 6.
[0050] Other suitable polymeric amines include polyethyleneimines
such as Lugalvan.TM. G35 available from BASF.
[0051] The invention can now be illustrated by reference to the
following non-limiting examples:
[0052] The following details apply to the examples:
[0053] POLYLAC.TM. PA727 is a commercial grade of acrylonitrile
butadiene styrene (ABS) manufactured by Chi Mei, Inc., Taiwan.
[0054] The following products described in the examples are
available from MacDermid, Inc. and were used in accordance with
their product data sheets.
TABLE-US-00001 Product Description ND7 Supreme .TM. Pre-etch
cleaning/degreasing solution Macuplex .TM. STR Wetting agent
Macuplex .TM. 9338 Neutralizing treatment for hexavalent chromium
Macuplex .TM. D-34C Activating solution based on colloidal
suspension of metallic palladium particles in a stannous chloride
medium Macuplex .TM. 9369 Post-activator acidic treatment to
improve the autocatalytic nature of the activated surface Macuplex
.TM. J-64 Electroless nickel plating bath
[0055] Infra-red (IR) instrument and analysis details: [0056]
Instrument--PerkinElmer spectrum 100 FTIR spectrometer [0057]
Analysis details: [0058] Attenuated total reflectance (ATR) mode
[0059] Wavenumber range--4000-6000 cm.sup.-1 [0060] Number of
scans--8
EXAMPLE 1
[0060] [0061] Untreated POLYLAC.TM. PA727 [0062] The Infra-Red
analysis obtained from untreated ABS is shown in FIG. 1.
EXAMPLE 2
[0062] [0063] POLYLAC.TM. PA727 processed through a chromic
acid/sulfuric etch solution of the prior art.
TABLE-US-00002 [0063] Temperature Process Details (.degree. C.)
Time ND7 Supreme .TM. 50 2 minutes Water rinse Ambient 1
minute.sup. Etch 4M chromic acid 68 7 minutes 3.6M sulfuric acid 1
ml/l Macuplex STR Water rinse Ambient 2 minutes Macuplex .TM. 9338
30 2 minutes Water rinse Ambient 1 minute.sup. Dry Infra-Red
analysis
[0064] The infra-red spectrum obtained is shown in FIGS. 2A and
2B.
[0065] In the following examples 3-9, the chromium free etch
solution is contained in a 2-compartment glass cell separated by a
glass frit, with the etching solution being the anolyte (the
catholyte being of the same composition with the exception of the
silver nitrate being absent in the catholyte). The anode and
cathode materials were platinized titanium mesh and the anodic
current density used was 32.5 mA/cm.sup.2. This system was used to
electrochemically oxidize the silver ions to the +2 oxidation
state.
[0066] A mechanical stirrer bar was used to provide agitation and
the cell was electrolyzed by a minimum of two hours before use in
order to generate a significant quantity of silver (II) ions.
Example 3
[0067] Example 3 illustrates an ABS substrate processed through
non-chrome etch solution:
TABLE-US-00003 Temperature Process Details (.degree. C.) Time ND7
Supreme .TM. 50 2 minutes Water rinse Ambient 1 minute.sup. Etch
0.1M AgNO.sub.3 50 6 minutes 9M HNO.sub.3 7 ml/l Macuplex STR Water
rinse Ambient 2 minutes Dry Infra-Red analysis
[0068] The infra-red spectrum obtained is shown in FIG. 3A and 3B.
FIGS. 3A and 3B depict the FTIR spectrum of POLYLAC.TM. PA727
etched in an acidic solution containing nitrate ions and silver
ions. FIG. 3A shows the results at 4000-600 cm.sup.-1 and FIG. 3B
shows the results at 2000-600 cm.sup.-1. The "*" in the FIGS. 3A
and 3B indicate peaks that have appeared due to the etching
process.
EXAMPLE 4
[0069] Example 4 illustrates an ABS substrate processed through a
non-chrome etch solution and an ammonia post-treatment
solution.
TABLE-US-00004 Temperature Process Details (.degree. C.) Time ND7
Supreme .TM. 50 2 minutes Water rinse Ambient 1 minute.sup. Etch
Same as Example 3 50 6 minutes Water rinse Ambient 2 minutes
Ammonia treatment 40 ml/l of 0.880SG 50 5 minutes ammonia solution
(or 0.68M NH.sub.3) Water rinse Ambient 1 minute.sup. Dry Infra-Red
analysis
[0070] The infra-red spectrum obtained is shown in FIGS. 4A and 4B.
FIGS. 4A and 4B depict the FTIR spectrum of POLYLAC.TM. PA727
etched in an acidic solution containing nitrate ions and silver
ions and post treated in an ammonia solution. FIG. 4A shows the
results at 4000-600 cm.sup.-1 and FIG. 4B shows the results at
2000-600 cm.sup.-1. As can be seen in FIGS. 4A and 4B, there is an
absence of the peaks introduced in Example 3. In this example, the
"*" in FIG. 4B indicates a new peak introduced by treatment with an
amine.
EXAMPLE 5
[0071] Example 5 illustrates an ABS substrate processed through a
non-chrome etch solution an ammonia post-treatment solution and up
to the electroless nickel stage:
TABLE-US-00005 Temperature Process Details (.degree. C.) Time ND7
Supreme .TM. 50 2 minutes Water rinse Ambient 1 minute.sup. Etch
Same as Example 3 50 6 minutes Water rinse Ambient 2 minutes
Ammonia treatment 40 ml/l of 0.880 SG 50 5 minutes ammonia solution
Water rinse Ambient 1 minute.sup. Acid rinse 2.8M HCl Ambient 1
minute.sup. Macuplex .TM. D-34C 27 3 minutes Water rinse Ambient 1
minute.sup. Macuplex .TM. 9369 48 2 minutes Water rinse Ambient 1
minute.sup. Macuplex .TM. J-64 32 7 minutes Water rinse Ambient 1
minute.sup. Dry
[0072] The result was full electroless nickel metallization.
EXAMPLE 6
[0073] Example 6 illustrates an ABS substrate processed through a
non-chrome etch solution, deionized water post-treatment solution
and up to the electroless nickel stage:
TABLE-US-00006 Temperature Process Details (.degree. C.) Time ND7
Supreme .TM. 50 .sup. 2 minutes Water rinse Ambient 1 minute Etch
0.1M AgNO.sub.3 55 .sup. 6 minutes 6M HNO.sub.3 6M H.sub.2SO.sub.4
1 ml/l Macuplex STR Water rinse Ambient .sup. 5 minutes Hot water
rinse 80 10 minutes.sup. Water rinse Ambient 1 minute Acid rinse
2.8M HCl Ambient 1 minute Macuplex .TM. D-34C 27 .sup. 3 minutes
Water rinse Ambient 1 minute Macuplex .TM. 9369 48 .sup. 2 minutes
Water rinse Ambient 1 minute Macuplex .TM. J-64 32 .sup. 7 minutes
Water rinse Ambient 1 minute Dry
[0074] The result was no electroless nickel metallization.
EXAMPLE 7
[0075] Example 7 illustrates an ABS substrate processed through a
non-chrome etch solution, a N,N-dimethylethanolamine post treatment
solution and up to the electroless nickel stage:
TABLE-US-00007 Temperature Process Details (.degree. C.) Time ND7
Supreme .TM. 50 .sup. 2 minutes Water rinse Ambient 1 minute Etch
Same as Example 6 55 .sup. 6 minutes Water rinse Ambient .sup. 2
minutes Amine treatment 10 g/L N,N- 80 10 minutes.sup.
dimethylethanolamine Water rinse Ambient 1 minute Acid rinse 2.8M
HCl Ambient 1 minute Macuplex .TM. D-34C 27 .sup. 3 minutes Water
rinse Ambient 1 minute Macuplex .TM. 9369 48 .sup. 2 minutes Water
rinse Ambient 1 minute Macuplex .TM. J-64 32 .sup. 7 minutes Water
rinse Ambient 1 minute Dry
[0076] The result was full electroless nickel metallization.
EXAMPLE 8
[0077] Example 8 illustrates an ABS substrate processed through a
non-chrome etch solution, a diethylene triamine post treatment
solution and up to the electroless nickel stage:
TABLE-US-00008 Temperature Process Details (.degree. C.) Time ND7
Supreme .TM. 50 .sup. 2 minutes Water rinse Ambient 1 minute Etch
0.1M AgNO.sub.3 55 12 minutes.sup. 6M HNO.sub.3 3M H.sub.2SO.sub.4
Water rinse Ambient .sup. 2 minutes Amine treatment 15 g/L
diethylene 50 .sup. 5 minutes triamine Water rinse Ambient 1 minute
Acid rinse 2.8M HCl Ambient 1 minute Macuplex .TM. D-34C 27 .sup. 3
minutes Water rinse Ambient 1 minute Macuplex .TM. 9369 48 .sup. 2
minutes Water rinse Ambient 1 minute Macuplex .TM. J-64 32 .sup. 7
minutes Water rinse Ambient 1 minute Dry
[0078] The result was full electroless nickel metallization.
EXAMPLE 9
[0079] Example 9 illustrates an ABS substrate processed through a
non-chrome etch solution, a polymeric quaternary amine post
treatment solution and up to the electroless nickel stage:
TABLE-US-00009 Temperature Process Details (.degree. C.) Time ND7
Supreme .TM. 50 2 minutes Water rinse Ambient 1 minute.sup. Etch
Same as Example 8 50 6 minutes Water rinse Ambient 2 minutes Amine
treatment 15 g/L Mirapol WT, a 50 5 minutes polymeric quaternary
amine available from Rhodia Water rinse Ambient 1 minute.sup. Acid
rinse 2.8M HCl Ambient 1 minute.sup. Macuplex .TM. D-34C 27 3
minutes Water rinse Ambient 1 minute.sup. Macuplex .TM. 9369 48 2
minutes Water rinse Ambient 1 minute.sup. Macuplex .TM. J-64 32 7
minutes Water rinse Ambient 1 minute.sup. Dry
[0080] The result was full electroless nickel metallization.
* * * * *