U.S. patent application number 14/004011 was filed with the patent office on 2013-12-26 for electro copper plating additive and electro copper plating bath.
This patent application is currently assigned to C. UYEMURA & CO., LTD.. The applicant listed for this patent is Hironori Sugiura, Hiroki Uchida. Invention is credited to Hironori Sugiura, Hiroki Uchida.
Application Number | 20130341199 14/004011 |
Document ID | / |
Family ID | 46930947 |
Filed Date | 2013-12-26 |
United States Patent
Application |
20130341199 |
Kind Code |
A1 |
Uchida; Hiroki ; et
al. |
December 26, 2013 |
ELECTRO COPPER PLATING ADDITIVE AND ELECTRO COPPER PLATING BATH
Abstract
Provided are an additive for electro copper plating and an
electro copper plating bath containing the additive, wherein the
additive forms a plating film uniformly in a range of from a low
current density portion to a high current density portion and
thereby gives good glossiness, and is not consumed at the time of
non-usage thereof. In the present invention, an additive for
electro copper plating including a block polymer compound expressed
by the following general formula (1) is added to an electro copper
plating bath. (Here, in the formula, R represents an alkyl group or
an alkenyl group having a linear-chain or branched-chain structure
and having a carbon number of 1 to 15, m is an integer of from 1 to
30, and n is an integer of from 1 to 40.) ##STR00001##
Inventors: |
Uchida; Hiroki; (Osaka,
JP) ; Sugiura; Hironori; (Osaka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Uchida; Hiroki
Sugiura; Hironori |
Osaka
Osaka |
|
JP
JP |
|
|
Assignee: |
C. UYEMURA & CO., LTD.
Osaka-shi, Osaka
JP
|
Family ID: |
46930947 |
Appl. No.: |
14/004011 |
Filed: |
March 23, 2012 |
PCT Filed: |
March 23, 2012 |
PCT NO: |
PCT/JP2012/057594 |
371 Date: |
September 9, 2013 |
Current U.S.
Class: |
205/296 |
Current CPC
Class: |
C25D 3/38 20130101 |
Class at
Publication: |
205/296 |
International
Class: |
C25D 3/38 20060101
C25D003/38 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 28, 2011 |
JP |
2011-070667 |
Claims
1. An additive for electro copper plating, comprising a block
polymer compound expressed by a following general formula (1):
##STR00004## wherein R represents an alkyl group or an alkenyl
group having a linear-chain or branched-chain structure and having
a carbon number 1 to 15, m is an integer of from 1 to 30, and n is
an integer of from 1 to 40.
2. The additive for electro copper plating according to claim 1,
wherein the block polymer compound is obtained in such a manner
that, under an atmosphere of inert gas, an alkyl alcohol or an
alkenyl alcohol having a carbon number of 1 to 15 is made to
undergo an addition reaction with propylene oxide, and then
ethylene oxide is added and reacted.
3. An electro copper plating bath containing the additive for
electro copper plating according to claim 1.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an electro copper plating
additive and an electro copper plating bath, particularly relates
to an electro copper plating additive suitable as a brightener for
a copper sulfate plating bath and an electro copper plating bath
containing the additive. The present application asserts priority
rights based on JP Patent Application 2011-070667 filed in Japan on
Mar. 28, 2011. The total contents of disclosure of the patent
application of the senior filing date are to be incorporated by
reference into the present application.
BACKGROUND OF THE INVENTION
[0002] To provide a glossy copper plating film, a brightener has
been conventionally added to an electro copper plating bath. As the
brightener, for example, organic thio compounds and high molecular
organic compounds containing oxygen have been known. (Refer to PTL
1 or 2, for example.) As the organic thio compounds, disulfide
compounds, such as
NaO.sub.3SC.sub.3H.sub.6S--SC.sub.3H.sub.6SO.sub.3Na, have been
widely used, while, as the high molecular organic compounds
containing oxygen, oxyalkylene polymer, polyethylene glycol,
polypropylene glycol, and the like have been used.
[0003] Furthermore, as a brightener other than the above-mentioned
compounds, there has been used a polymer obtained by adding an
ethylene oxide to a polypropylene glycol and expressed by the
following general formula:
H-(EO)a-(PO)m-(EO)b-H
wherein EO represents an oxyethylene group, PO represents an
oxypropylene group, and n=a+b.
[0004] However, these brighteners, which have been conventionally
used, do not provide sufficient glossiness and do not have throwing
power in a low current density portion of a copper plating film,
whereby a rough film is formed. The cause for this is that, for
example, the polymer expressed by the above-mentioned general
formula has a molecular structure in which (PO)m, a hydrophobic
group, is sandwiched between (EO)n on both sides, and therefore the
effect of a hydrophobic group is weakened. As a result, when a
compound comprising this polymer was used as a brightener for an
electrolytic copper plating bath, current distribution was
disturbed in a low current density portion and a high current
density portion, and therefore uniform electrodeposition was
disturbed, and accordingly poor plating, such as occurrence of
minute pits and clouding, was caused.
[0005] Also, a brightener which is easily managed and not consumed
when not in use is desired for electro copper plating.
PRIOR-ART DOCUMENTS
Patent Document
[0006] PTL 1: Japanese Patent Application Laid-Open No. 2005-194608
[0007] PTL 2: Japanese Patent Application Laid-Open No,
2008-297221
SUMMARY OF THE INVENTION
[0008] The present invention is proposed in view of such
conventional actual circumstances, and aims at providing an
additive for electro copper plating and an electro copper plating
bath containing the additive, the additive forming an uniform
plating film in a range of from a low current density portion to a
high current density portion and thereby providing good glossiness,
and not being consumed at the time of non-usage thereof.
[0009] The present inventors earnestly studied to achieve the
above-mentioned aim, and, as a result, found that when a block
polymer compound having a higher effect of a hydrophobic group is
used as an additive, a plating film is uniformly formed in a range
of from a low current density portion to a high current density
portion and thereby good glossiness can be provided, and completed
the present invention.
[0010] In other words, an additive for electro copper plating
according to the present invention comprises a block polymer
compound expressed by a following general formula (1):
##STR00002##
[0011] (wherein R represents an alkyl group or an alkenyl group
having a linear-chain or branched-chain structure and has a carbon
number of 1 to 15, m is an integer of from 1 to 30, and n is an
integer of from 1 to 40.)
[0012] An electro copper plating bath according to the present
invention contains the additive comprising the block polymer
compound expressed by the above-mentioned general formula (1).
Effects of Invention
[0013] According to the present invention, the additive enables
plating film to form uniformly in a range of from a low current
density portion to a high current density portion and to provide
good glossiness, and also the additive is not consumed when not in
use, whereby a good and stable plating film can be formed.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Hereinafter, an additive for electro copper plating and an
electro copper plating bath containing the additive according to
the present embodiment will be explained in detail.
[0015] The additive for electro copper plating according to the
present embodiment comprises a block polymer compound expressed by
a following general formula (1).
##STR00003##
[0016] Here, in the general formula (1), R represents an alkyl
group or an alkenyl group having a linear-chain or branched-chain
structure and having a carbon number of 1 to 15, m is an integer of
from 1 to 30, and n is an integer of from 1 to 40.
[0017] Examples of R which is an alkyl group or an alkenyl group
having a linear-chain or branched-chain structure and having a
carbon number of 1 to 15 include a methyl group, an ethyl group, an
n-propyl group, an allyl group, an n-butyl group, an n-pentyl
group, an n-hexyl group, a 1-methylhexyl group, a 2-ethylhexyl
group, an n-heptyl group, an n-octyl group, an n-nonyl group, an
n-decyl group, an n-undecyl group, an n-dodecyl group, an
n-tridecyl group, an n-tetradecyl group, and an n-pentadecyl
group.
[0018] Furthermore, m and n in the general formula (1) may be
suitably set in accordance with the above-mentioned type of R.
Specifically, as a carbon number of R increases, hydrophobicity
increases accordingly, and therefore by adjusting molar ratios of m
and n in accordance with the type of R, the additive can have
appropriate solubility in a plating bath. Also, m and n may be
preferably set so that a molecular weight of the block polymer
expressed by the above-mentioned general formula (1) is 500 to
2000.
[0019] As shown in the above-mentioned general formula (1), this
additive has a structure in which one end at the side of an
oxypropylene group is capped with an alkyl group or an alkenyl
group. Thus, by capping an end of an oxypropylene group with an
alkyl group or an alkenyl group, the oxypropylene group can have a
higher effect as a hydrophobic group.
[0020] Furthermore, the additive shown in the above-mentioned
general formula (1) has a fixed sequence of an oxypropylene group
(PO) and an oxyethylene group (EO), and is a block polymer
constantly having a structure of R--O--(PO)m-(EO)n-H. Thus, the
oxypropylene group ((PO)m), whose end is capped with an alkyl group
or an alkenyl group as mentioned above, allows a portion of
"R--O--(PO)m" in the above-mentioned general formula (1) to act
together as a hydrophobic group, whereby high hydrophobicity is
provided.
[0021] An effect expected from this is such that a hydrophobic
group of a compound is generally extruded from the water to an
interface, and hence, when a plated material is immersed in an
solution, a plated surface of the plated material becomes an
interface, and the additive having high hydrophobicity is condensed
on the plated surface, whereby an effect of the additive is
increased. As a result, it is considered that an effect of the
additive is exerted throughout from a low current density portion
to a high current density portion, whereby a uniform plating film
is formed and accordingly good glossiness can be provided.
[0022] Furthermore, such block polymer enables appropriate
solubility to be provided thereto by the oxyethylene group at the
other end of the structure of the additive; allows a polymer
compound to be satisfactorily dissolved in an electro copper
plating bath and also to be maintained stably in the plating bath;
and control the chronological consumption when electrolysis
treatment is not in use.
[0023] The block polymer compound expressed by the above-mentioned
general formula (1) can be manufactured by the following method,
for example. That is, under an atmosphere of inert gas, such as
nitrogen gas, an alkyl alcohol or an alkenyl alcohol having a
carbon number of 1 to 15 is first made to undergo an addition
reaction with propylene oxide. After the addition reaction with
propylene oxide, ethylene oxide is next added to induce an addition
reaction with the ethylene oxide, whereby the block polymer
compound is obtained.
[0024] Thus, an alkyl alcohol or an alkenyl alcohol having a carbon
number of 1 to 15 is made to undergo an addition reaction with
propylene oxide, and then ethylene oxide is added and reacted to
carry out synthesis, whereby there can be produced the block
polymer compound having a block unit with a certain structure in
which (EO)n is added to (PO)m capped with an alkyl group or an
alkenyl group.
[0025] A reaction temperature in the method of manufacturing the
block polymer compound is not particularly limited, but preferably
90 to 160 degrees C. With a reaction temperature of not less than
90 degrees C., an appropriate reaction rate can be realized and
thereby addition reactions with propylene oxide and ethylene oxide
can be made to occur efficiently. On the other hand, with a
reaction temperature of not more than 160 degrees C., formation of
a side reaction product and the like is controlled, whereby a yield
of a block polymer compound to be formed can be increased. Note
that, in the addition reaction of an alkyl alcohol with propylene
oxide and the subsequent addition reaction with ethylene oxide, it
is preferable that, after the addition reaction with propylene
oxide at the above-mentioned temperature of 90 to 160 degrees C.,
cooling is performed and then the addition reaction with ethylene
oxide is carried out under the same temperature condition.
[0026] Furthermore, a reaction time is not particularly limited and
different depending on a reaction temperature, but preferably
within 15 hours in each of the addition reactions with propylene
oxide and with ethylene oxide. With a reaction time of not more
than 15 hours, formation of a side reaction product and the like is
controlled, whereby a yield of a block polymer compound to be
formed can be increased.
[0027] Furthermore, the addition reactions are preferably carried
out under pressure, and a pressure at the time of starting an
addition reaction is preferably 2 to 5 kg/cm.sup.2.
[0028] When a block polymer compound expressed by the
above-mentioned general formula (1) is used as an additive for
electro copper plating, an addition concentration at this time is
preferably 0.05 to 1.0 g/L. With an addition concentration of not
less than 0.05 g/L, a plating film having sufficient glossiness can
be formed. On the other hand, with an addition concentration of not
more than 1.0 g/L, a current density range effectively available is
prevented from becoming narrow, and a good plating film can be
uniformly formed in a range of from a low current density portion
to a high current density portion.
[0029] Next, there will be explained an electro copper plating bath
to which an additive comprising the above-mentioned block polymer
compound expressed by the general formula (1) is added, and
explained a plating treatment using the electro copper plating
bath. The electro copper plating bath is not particularly limited,
but a copper sulfate plating bath is especially preferable. By
adding the above-mentioned block polymer compound to a copper
sulfate plating bath, a copper plating film having excellent
glossiness can be uniformly formed in a wide range of current
density, and the copper sulfate plating bath can be suitably used
as a plating bath for decorative plating.
[0030] Specifically, the copper sulfate plating bath may be, for
example, a plating bath having a basic composition comprising 50 to
250 g/L of copper sulfate (Cu.sub.2SO.sub.4.5H.sub.2O) and 50 to
250 g/L of concentrated sulfuric acid. Note that the copper sulfate
plating bath is made to usually contain a very small amount
(approximately 10 to 200 mg/L) of chloride ions. Specifically,
chloride ions can be contained, for example, by adding
water-soluble chloride, such as NaCl.
[0031] Note that a known additive may be further added to the
above-mentioned electro copper plating bath to further improve
glossiness and smoothness. Specifically, for example, an organic
thio compound, organic acid amides, an oxygen-containing high
molecular weight organic compound, or the like can be added.
[0032] A condition of the plating treatment using the
above-mentioned electro copper plating bath is a pH of not more
than 1. Furthermore, a plating temperature in a range of 20 to 50
degrees C. and a cathode current density of 0.1 to 8 A/dm.sup.2 are
preferable. Furthermore, a copper plate or an insoluble anode may
be used as an anode. Furthermore, in order to form a plating film
having more uniform glossiness, it is preferable that agitation,
such as air agitation or cathode rocking, is sufficiently carried
out.
[0033] A material to be plated for which the above-mentioned
plating treatment is provided is not particularly limited, but, for
example, in order to perform decorative plating for a material to
be plated, such as plastics, an electro copper plating bath to
which the above-mentioned additive is added may be suitably used.
Note that other materials, such as a printed-circuit board and
electrical and electronic components, each having through-holes,
may be subjected to the plating treatment. Thus, the electro copper
plating bath to which the above-mentioned additive is added can be
widely applied for decorative use to functional purpose.
EXAMPLES
[0034] Hereafter, specific examples according to the present
invention will be explained. Note that the present invention is not
limited to any of the following examples.
[0035] In each example explained below, a block polymer
(R--O--(PO)m-(EO)n-H) shown in Table 1 was synthesized, and plating
treatment was performed using a copper plating bath to which the
block polymer compound was added as an additive, and then a plating
film precipitated and formed was evaluated. Note that air was blown
into the copper plating bath to perform sufficient agitation, in
particular, air was blown against a material to be plated so that
the vicinity of a cathode was agitated.
TABLE-US-00001 TABLE 1 Block Polymer (R--O--(PO)m-(EO)n-H) R Carbon
Number m:n Example 1 n-propyl 3 15:15 Example 2 allyl 3 15:15
Example 3 n-butyl 4 10:15 Example 4 n-hexyl 6 5:20 Example 5
2-ethylhexyl 8 3:25 Example 6 dodecyl 12 2:30
Example 1
Synthesis of Block Polymer
[0036] In an airtight reaction vessel, 600 g (10 mol) of n-propanol
and 5.6 g (0.1 mol) of potassium hydroxide were taken, and under a
nitrogen gas atmosphere, subjected to an addition reaction with 870
g (15 mol) of propylene oxide at 90 to 130 degrees C. under a
pressure of 2 to 5 kg/cm.sup.2. After completing the addition
reaction with the propylene oxide, the reaction vessel was cooled,
and then 660 g (15 mol) of ethylene oxide was added thereto and
reacted under the same conditions.
[0037] Next, 50 g of a synthetic adsorbent (Kyoward 600,
manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the
reaction vessel and agitated at 70 degrees C. for 30 minutes, and
then filtered, whereby 2070 g of polyoxyethylene (15)
polyoxypropylene (15) propyl ether was obtained.
[0038] (Plating Treatment and Plating Film Evaluation)
TABLE-US-00002 Copper sulfate (Cu.sub.2SO.sub.4.cndot.5H.sub.2O)
200 g/L Concentrated Sulfuric Acid 50 g/L NaCl 115 mg/L
[0039] To a copper sulfate plating solution comprising the above
composition, 10 mg/L of bis-(.omega.-sulfopropyl)-disulfide
disodium salt, 50 mg/L of diazotized diethyl safranine, and 0.2 g/L
of polyoxyethylene (15) polyoxypropylene (15) propyl ether
synthesized as mentioned above were added as additives to make a
plating bath, and by using the thus obtained plating bath, plating
treatment was performed with a Hull cell tester at a total current
of 2 A for 10 minutes. Note that conditions of the plating
treatment were pH<1, a temperature of 25 degrees C., and a
cathode current density of 0.15 to 4 A/dm.sup.2.
[0040] As a result, a precipitate having good glossiness was
uniformly formed in a range of from a low current density portion
to a high current density portion.
[0041] Furthermore, also in the case where plating treatment was
performed in the same manner after a copper plate was put into the
above-mentioned Hull cell tester and left therein overnight, a
precipitate having good glossiness was uniformly formed as is the
case with the first plating treatment. Hence, it was found that the
additive was stably maintained without being consumed even at the
time of non-usage thereof.
Example 2
Synthesis of B lock Polymer
[0042] In an airtight reaction vessel, 580 g (10 mol) of allyl
alcohol (2-propen-1-ol) and 5.6 g (0.1 mol) of potassium hydroxide
were taken, and under a nitrogen gas atmosphere, subjected to an
addition reaction with 870 g (15 mol) of propylene oxide at 90 to
130 degrees C. under a pressure of 2 to 5 kg/cm.sup.2. After
completing the addition reaction with the propylene oxide, the
reaction vessel was cooled, and then 660 g (15 mol) of ethylene
oxide was added thereto and reacted under the same conditions.
[0043] Next, 50 g of a synthetic adsorbent (Kyoward 600,
manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the
reaction vessel and agitated at 70 degrees C. for 30 minutes, and
then filtered, whereby 2050 g of polyoxyethylene (15)
polyoxypropylene (15) allyl ether was obtained.
[0044] (Plating Treatment and Plating Film Evaluation)
[0045] In Example 2, plating treatment was performed using a Hull
cell tester with the same manner as in Example 1, except that there
was used a copper sulfate plating bath to which 10 mg/L of
bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50 mg/L of
diazotized diethyl safranine, and 0.2 g/L of polyoxyethylene (15)
polyoxypropylene (15) allyl ether synthesized as mentioned above
were added as additives.
[0046] As a result, a precipitate having good glossiness was
uniformly formed in a range of from a low current density portion
to a high current density portion. Furthermore, also in the case
where plating treatment was performed in the same manner after a
copper plate was put into the above-mentioned Hull cell tester and
left therein overnight, a precipitate having good glossiness was
uniformly formed as is the case with the first plating
treatment.
Example 3
Synthesis of Block Polymer
[0047] In an airtight reaction vessel, 740 g (10 mol) of n-butanol
and 5.6 g (0.1 mol) of potassium hydroxide were taken, and under a
nitrogen gas atmosphere, subjected to an addition reaction with 580
g (10 mol) of propylene oxide at 90 to 130 degrees C. under a
pressure of 2 to 5 kg/cm.sup.2. After completing the addition
reaction with the propylene oxide, the reaction vessel was cooled,
and then 660 g (15 mol) of ethylene oxide was added thereto and
reacted under the same conditions.
[0048] Next, 50 g of a synthetic adsorbent (Kyoward 600,
manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the
reaction vessel and agitated at 70 degrees C. for 30 minutes, and
then filtered, whereby 1920 g of polyoxyethylene (15)
polyoxypropylene (10) butyl ether was obtained.
[0049] (Plating Treatment and Plating Film Evaluation)
[0050] In Example 3, plating treatment was performed using a Hull
cell tester with the same manner as in Example 1, except that there
was used a copper sulfate plating bath to which 10 mg/L of
bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50 mg/L of
diazotized diethyl safranine, and 0.2 g/L of polyoxyethylene (15)
polyoxypropylene (10) butyl ether synthesized as mentioned above
were added as additives.
[0051] As a result, a precipitate having good glossiness was
uniformly formed in a range of from a low current density portion
to a high current density portion. Furthermore, also in the case
where plating treatment was performed in the same manner after a
copper plate was put into the above-mentioned Hull cell tester and
left therein overnight, a precipitate having good glossiness was
uniformly formed as is the case with the first plating
treatment.
Example 4
Synthesis of Block Polymer
[0052] In an airtight reaction vessel, 1020 g (10 mol) of n-hexanol
and 5.6 g (0.1 mol) of potassium hydroxide were taken, and under a
nitrogen gas atmosphere, subjected to an addition reaction with 290
g (5 mol) of propylene oxide at 90 to 130 degrees C. under a
pressure of 2 to 5 kg/cm.sup.2. After completing the addition
reaction with the propylene oxide, the reaction vessel was cooled,
and then 880 g (20 mol) of ethylene oxide was added thereto and
reacted under the same conditions.
[0053] Next, 50 g of a synthetic adsorbent (Kyoward 600,
manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the
reaction vessel and agitated at 70 degrees C. for 30 minutes, and
then filtered, whereby 2130 g of polyoxyethylene (20)
polyoxypropylene (5) hexyl ether was obtained.
[0054] (Plating Treatment and Plating Film Evaluation)
[0055] In Example 4, plating treatment was performed using a Hull
cell tester with the same manner as in Example 1, except that there
was used a copper sulfate plating bath to which 10 mg/L of
bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50 mg/L of
diazotized diethyl safranine, and 0.2 g/L of polyoxyethylene (20)
polyoxypropylene (5) hexyl ether synthesized as mentioned above
were added as additives.
[0056] As a result, a precipitate having good glossiness was
uniformly formed in a range of from a low current density portion
to a high current density portion. Furthermore, also in the case
where plating treatment was performed in the same manner after a
copper plate was put into the above-mentioned Hull cell tester and
left therein overnight, a precipitate having good glossiness was
uniformly formed as is the case with the first plating
treatment.
Example 5
Synthesis of Block Polymer
[0057] In an airtight reaction vessel, 1300 g (10 mol) of
2-ethylhexanol and 5.6 g (0.1 mol) of potassium hydroxide were
taken, and under a nitrogen gas atmosphere, subjected to an
addition reaction with 174 g (3 mol) of propylene oxide at 90 to
130 degrees C. under a pressure of 2 to 5 kg/cm.sup.2. After
completing the addition reaction with the propylene oxide, the
reaction vessel was cooled, and then 1100 g (25 mol) of ethylene
oxide was added thereto and reacted under the same conditions.
[0058] Next, 50 g of a synthetic adsorbent (Kyoward 600,
manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the
reaction vessel and agitated at 70 degrees C. for 30 minutes, and
then filtered, whereby 2500 g of polyoxyethylene (25)
polyoxypropylene (3) 2-ethylhexyl ether was obtained.
[0059] (Plating Treatment and Plating Film Evaluation)
[0060] In Example 5, plating treatment was performed using a Hull
cell tester with the same manner as in Example 1, except that there
was used a copper sulfate plating bath to which 10 mg/L of
bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50 mg/L of
diazotized diethyl safranine, and 0.2 g/L of polyoxyethylene (25)
polyoxypropylene (3) 2-ethylhexyl ether synthesized as mentioned
above were added as additives.
[0061] As a result, a precipitate having good glossiness was
uniformly formed in a range of from a low current density portion
to a high current density portion. Furthermore, also in the case
where plating treatment was performed in the same manner after a
copper plate was put into the above-mentioned Hull cell tester and
left therein overnight, a precipitate having good glossiness was
uniformly formed as is the case with the first plating
treatment.
Example 6
Synthesis of Block Polymer
[0062] In an airtight reaction vessel, 1860 g (10 mol) of
1-dodecanol and 5.6 g (0.1 mol) of potassium hydroxide were taken,
and under a nitrogen gas atmosphere, subjected to an addition
reaction with 116 g (2 mol) of propylene oxide at 90 to 130 degrees
C. under a pressure of 2 to 5 kg/cm.sup.2. After completing the
addition reaction with the propylene oxide, the reaction vessel was
cooled, and then 1320 g (30 mol) of ethylene oxide was added
thereto and reacted under the same conditions.
[0063] Next, 50 g of a synthetic adsorbent (Kyoward 600,
manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the
reaction vessel and agitated at 70 degrees C. for 30 minutes, and
then filtered, whereby 3200 g of polyoxyethylene (30)
polyoxypropylene (2) dodecyl ether was obtained.
[0064] (Plating Treatment and Plating Film Evaluation)
[0065] In Example 6, plating treatment was performed using a Hull
cell tester with the same manner as in Example 1, except that there
was used a copper sulfate plating bath to which 10 mg/L of
bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50 mg/L of
diazotized diethyl safranine, and 0.2 g/L of polyoxyethylene (30)
polyoxypropylene (2) dodecyl ether synthesized as mentioned above
were added as additives.
[0066] As a result, a precipitate having good glossiness was
uniformly formed in a range of from a low current density portion
to a high current density portion. Furthermore, also in the case
where plating treatment was performed in the same manner after a
copper plate was put into the above-mentioned Hull cell tester and
left therein overnight, a precipitate having good glossiness was
uniformly formed as is the case with the first plating
treatment.
Comparative Example 1
Plating Treatment and Plating Film Evaluation
[0067] In Comparative Example 1, plating treatment was performed
using a Hull cell tester with the same manner as in Example 1,
except that there was used a copper sulfate plating bath to which
10 mg/L of bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50
mg/L of diazotized diethyl safranine, and 0.2 g/L of polyethylene
glycol were added as additives; and a plating film thereby
precipitated and formed was evaluated. Note that, also in this
Comparative Example 1 and the following Comparative Examples 2 and
3, air was blown into the copper sulfate plating bath and agitation
was sufficiently carried out.
[0068] As a result, the precipitate had good glossiness, but minute
pits and white clouding were caused and the precipitate was not
formed uniformly in a range of from a low current density portion
to a high current density portion, and thus the plating film had a
poor appearance.
Comparative Example 2
Plating Treatment and Plating Film Evaluation
[0069] In Comparative Example 2, plating treatment was performed
using a Hull cell tester with the same manner as in Example 1,
except that there was used a copper sulfate plating bath to which
10 mg/L of bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50
mg/L of diazotized diethyl safranine, and 0.2 g/L of polypropylene
glycol were added as additives; and a plating film thereby
precipitated and formed was evaluated.
[0070] As a result, the precipitate had good glossiness, but minute
pits and white clouding were caused and the precipitate was not
formed uniformly in a range of from a low current density portion
to a high current density portion, and thus the plating film had a
poor appearance.
Comparative Example 3
Plating Treatment and Plating Film Evaluation
[0071] In Comparative Example 3, plating treatment was performed
using a Hull cell tester with the same manner as in Example 1,
except that there was used a copper sulfate plating bath to which
10 mg/L of bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50
mg/L of diazotized diethyl safranine, and 0.2 g/L of block polymer
(H-(EO)a-(PO)m-(EO)b-H, wherein m=17, and n=a+b=9) obtained by
adding ethylene oxide to polypropylene glycol were added as
additives; and a plating film thereby precipitated and formed was
evaluated.
[0072] As a result, the precipitate had good glossiness, but minute
pits and white clouding were caused and the precipitate was not
formed uniformly in a range of from a low current density portion
to a high current density portion, and thus the plating film had a
poor appearance.
Comparative Example 4
Plating Treatment and Plating Film Evaluation
[0073] In Comparative Example 4, plating treatment was performed
using a Hull cell tester with the same manner as in Example 1,
except that there was used a copper sulfate plating bath to which
10 mg/L of bis-(.omega.-sulfopropyl)-disulfide disodium salt, 50
mg/L of diazotized diethyl safranine, and 0.2 g/L of random polymer
obtained by simultaneously adding ethylene oxide and propylene
oxide to n-butanol were added as additives, and a plating film
thereby precipitated and formed was evaluated.
[0074] As a result, the precipitate had good glossiness, but was a
stepped-surface plating which was precipitated with a step-like
change, and plating was not precipitated in a low current density
portion, and thus the plating film had a poor appearance.
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