U.S. patent application number 14/065120 was filed with the patent office on 2014-05-01 for metal nano particle and method for surface treating the same.
This patent application is currently assigned to SAMSUNG ELECTRO-MECHANICS CO., LTD.. The applicant listed for this patent is SAMSUNG ELECTRO-MECHANICS CO., LTD.. Invention is credited to Dong Hoon KIM, Kwang Myung Kim, Tae Ho KIM, Kwan LEE, Young Ku LYU, Jung Wook SEO.
Application Number | 20140119978 14/065120 |
Document ID | / |
Family ID | 50547416 |
Filed Date | 2014-05-01 |
United States Patent
Application |
20140119978 |
Kind Code |
A1 |
SEO; Jung Wook ; et
al. |
May 1, 2014 |
METAL NANO PARTICLE AND METHOD FOR SURFACE TREATING THE SAME
Abstract
Disclosed herein is a method for surface treating metal nano
particles, including: surface treating metal nano particles with an
alkanol amine containing solution.
Inventors: |
SEO; Jung Wook; (Suwon-si,
KR) ; KIM; Tae Ho; (Suwon-si, KR) ; LYU; Young
Ku; (Suwon-si, KR) ; Kim; Kwang Myung;
(Suwon-si, KR) ; LEE; Kwan; (Suwon-si, KR)
; KIM; Dong Hoon; (Suwon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG ELECTRO-MECHANICS CO., LTD. |
Suwon-si |
|
KR |
|
|
Assignee: |
SAMSUNG ELECTRO-MECHANICS CO.,
LTD.
Suwon-si
KR
|
Family ID: |
50547416 |
Appl. No.: |
14/065120 |
Filed: |
October 28, 2013 |
Current U.S.
Class: |
420/441 ;
134/2 |
Current CPC
Class: |
B22F 1/0018 20130101;
B22F 1/0062 20130101 |
Class at
Publication: |
420/441 ;
134/2 |
International
Class: |
C22B 7/00 20060101
C22B007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 29, 2012 |
KR |
10-2012-0120361 |
Claims
1. A method for surface treating metal nano particles, comprising:
surface treating metal nano particles with an alkanol amine
containing solution.
2. The method according to claim 1, wherein the surface treating of
the metal nano particles includes removing chloride ion adhered on
the surfaces of the metal nano particles with the alkanol
amine.
3. The method according to claim 1, wherein the surface treating of
the metal nano particles further includes substituting chloride ion
adhered on the surfaces of the metal nano particles into the
alkanol amine.
4. The method according to claim 1, wherein the surface treating of
the metal nano particles further includes: preparing a clean
solution containing at least one of ethanolamine, diethanaolamine,
and triethanolamine; and preparing a mixing solution by mixing the
metal nano particles with the cleaning solution.
5. The method according to claim 1, wherein a concentration of the
alkanol amine of the solution is 10 wt % or more.
6. The method according to claim 1, further comprising cleaning the
metal nano particles with alcohol or toluene to remove a surfactant
on the surfaces of the metal nano particles.
7. The method according to claim 1, further comprising: drying the
metal nano particles.
8. The method according to claim 7, wherein after the drying of the
metal nano particles, the concentration of the chloride ion on the
surfaces of the metal nano particles measured by using ion
chromatography is less than 100 ppm.
9. The method according to claim 8, wherein after the drying of the
metal nano particles, the concentration of the chloride ion on the
surfaces of the metal nano particles measured by using ion
chromatography is less than 10 ppm.
10. Metal nano particles, wherein the metal nano particles are
surface-treated with an alkanol amine containing solution and after
the metal nano particles are dried, the concentration of the
chloride ion on the surfaces of the metal nano particles measured
by using ion chromatography is less than 100 ppm.
11. The Metal nano particles according to claim 10, wherein the
concentration of the chloride ion is less than 10 ppm.
Description
CROSS REFERENCE(S) TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. Section
119 of Korean Patent Application Serial No. 10-2012-0120361
entitled "Metal Nano Particle and Method for Surface Treating the
Same" filed on Oct. 29, 2012, which is hereby incorporated by
reference in its entirety into this application.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to metal nano particles and a
method for surface treating the same, and more particularly, to a
method for surface treating metal nano particles capable of
effectively removing impurities that remain in metal nano particles
having high purity and metal nano particles synthesized
therefor.
[0004] 2. Description of the Related Art
[0005] Generally, a multi-layered chip element such as a
multi-layer ceramic capacitor (MLCC) is manufactured by forming
internal electrodes on a plurality of dielectric sheets, laminating
the sheets to manufacture a laminate, and forming external
electrodes on the laminate. As a material for the internal
electrode, a metal paste including various types of metal nano
particles is used. As an example, there is a technology of forming
internal electrodes of a multi-layer ceramic capacitor by using a
nickel paste including nickel nano particles.
[0006] The metal nano particles are synthesized by methods, such as
a liquid phase method, a gas phase method, a plasma and laser using
method, and the like. For example, the nickel nano particles may be
synthesized on an organic solvent including a surfactant. The
synthesized nickel nano particles may be easily dispersed by a
nonpolar solvent and are added with a polar solvent such as
alcohol, acetone, and the like, and recovered in a power form by a
centrifugal separator.
[0007] However, the method for synthesizing metal nano particles
may relatively easily remove the organic solvent and the surfactant
among the impurities remaining on the surfaces of the metal nano
particles but may hardly remove the organic matters among the
impurities. In particular, when a metal salt including chloride ion
is used as a reacting precursor, the chloride ion adhered on the
surfaces of the synthesized metal nano particles may not easily be
removed. The impurities such as chloride ion, and the like, degrade
the purity of the metal nano particles and when intending to form a
fine electrode that is a chip component by using the low-purity
metal nano particles, the electrode characteristics are
deteriorated.
RELATED ART DOCUMENT
Patent Document
[0008] (Patent Document 1) Korean Patent Laid-Open Publication No.
2001-0110693
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide metal nano
particles having high purity and a method for surface treating
metal nano particles.
[0010] Another object of the present invention is to provide
synthesized metal nano particles having low impurity concentration
and a method for surface treating metal nano particles capable of
effectively removing the impurities remaining on the surfaces of
metal nano particles.
[0011] Still another object of the present invention is to provide
metal nano particles having low chloride ion concentration and a
method for surface treating metal nano particles capable of
effectively removing the chloride ions remaining on surfaces of the
synthesized metal nano particles.
[0012] According to an exemplary embodiment of the present
invention, there is provided a method for surface treating metal
nano particles, including: surface treating metal nano particles
with an alkanol amine containing solution.
[0013] The surface treating of the metal nano particles may include
removing chloride ion adhered on the surfaces of the metal nano
particles with the alkanol amine.
[0014] The surface treating of the metal nano particles may further
include substituting chloride ion adhered on the surfaces of the
metal nano particles into the alkanol amine.
[0015] The surface treating of the metal nano particles may further
include: preparing a clean solution containing at least one of
ethanolamine, diethanaolamine, and triethanolamine; and preparing a
mixing solution by mixing the metal nano particles with the
cleaning solution.
[0016] A concentration of the alkanol amine of the solution may be
10 wt % or more.
[0017] The method for surface treating metal nano particles may
further include: cleaning the metal nano particles with alcohol or
toluene to remove a surfactant on the surfaces of the metal nano
particles.
[0018] The method for surface treating metal nano particles may
further include: drying the metal nano particles.
[0019] After the drying of the metal nano particles, the
concentration of the chloride ion on the surfaces of the metal nano
particles measured by using ion chromatography may be less than 100
ppm.
[0020] After the drying of the metal nano particles, the
concentration of the chloride ion on the surfaces of the metal nano
particles measured by using ion chromatography may be less than 10
ppm.
[0021] The metal nano particles may be surface-treated with an
alkanol amine containing solution and after the metal nano
particles are dried, the concentration of the chloride ion on the
surfaces of the metal nano particles measured by using ion
chromatography may be less than 100 ppm.
[0022] The concentration of the chloride ion may be less than 10
ppm.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a flow chart illustrating a method for surface
treating metal nano particles according to an exemplary embodiment
of the present invention.
[0024] FIG. 2 is a diagram for describing a process of surface
treating metal nano particles according to the exemplary embodiment
of the present invention.
[0025] FIG. 3 is a diagram illustrating a multi-layer ceramic
capacitor manufactured by using nickel nano particles to which the
method for surface treating metal nano particles according to the
exemplary embodiment of the present invention is applied.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Various advantages and features of the present invention and
methods accomplishing thereof will become apparent from the
following description of embodiments with reference to the
accompanying drawings. However, the present invention may be
modified in many different forms and it should not be limited to
the embodiments set forth herein. These embodiments may be provided
so that this disclosure will be thorough and complete, and will
fully convey the scope of the invention to those skilled in the
art. Like reference numerals throughout the description denote like
elements.
[0027] Terms used in the present specification are for explaining
the embodiments rather than limiting the present invention. Unless
explicitly described to the contrary, a singular form includes a
plural form in the present specification. The word "comprise" and
variations such as "comprises" or "comprising," will be understood
to imply the inclusion of stated constituents, steps, operations
and/or elements but not the exclusion of any other constituents,
steps, operations and/or elements.
[0028] Hereinafter, metal nano particles and a method for surface
treating metal nano particles according to an exemplary embodiment
of the present invention will be described in detail with reference
to the accompanying drawings.
[0029] FIG. 1 is a flow chart illustrating a method for surface
treating metal nano particles according to an exemplary embodiment
of the present invention and FIG. 2 is a diagram for describing a
principle of surface treating metal nano particles according to the
exemplary embodiment of the present invention.
[0030] Referring to FIGS. 1 and 2, the method for surface treating
metal nano particles according to the exemplary embodiment of the
present invention may include removing impurities 120 remaining on
surfaces of synthesized metal nano particles 110 (S110), treating
the metal nano particles 110 with an alkanol amine 130 containing
solution (S120), and drying the metal nano particles 110
(S130).
[0031] The metal nano particles 110 may be prepared by using
various methods of synthesizing nano particle. For example, various
kinds of the metal nano particles 110 may be prepared by using any
one of a gas phase method, a liquid phase method, and a plasma and
laser using method. As an example, the synthesizing of the metal
nano particles 110 may include preparing nickel nano particles
using a metal salt including chloride ion as a reacting precursor.
Various kinds of impurities 120 may remain in the synthesized metal
nano particles 110 in a form in which the impurities 120 are
adhered on the surfaces of the metal nano particles 110. The
impurities 120 may include an organic solvent, a surfactant,
organic matters, and the like. The organic matters may include
chloride ion.
[0032] The impurities 120 remaining on the surfaces of the metal
nano particles 110 may be removed (S110). The removing of the
impurities 120 may be performed by treating the metal nano
particles 110 with alcohol or toluene. The organic solvent or the
surfactant among the impurities 120 may be removed regardless of
polarity or non-polarity during the process of treating the metal
nano particles 110 with alcohol or toluene. However, it may be
difficult to remove the organic matters among the impurities only
by the treatment using the alcohol or the toluene. The organic
matters adhered on the surfaces of the metal nano particles 110 may
degrade the purity of the metal nano particles 110.
[0033] Therefore, the metal nano particles 110 may be
surface-treated by using the alkanol amine 130 (S120). The surface
treating of the metal nano particles 110 may be provided to remove
the organic matters among the impurities 120 adhered on the
surfaces of the metal nano particles 110. In more detail, in the
surface treating of the metal nano particles 110 using the alkanol
amine 130, the metal nano particles 110 may be mixed with a
cleaning solution. Therefore, the chloride ion that is the organic
matters adhered on the surface of the metal nano particles 110 is
substituted into the alkanol amine 130, such that the chloride ion
may be removed from the metal nano particles.
[0034] Here, as the cleaning solution, a solution including at
least one of ethanolamine (EA), diethanolamine (DEA),
triethanolamine (TEA) may be used. Further, the cleaning solution
may further be added with alcohol such as ethanol. In this case,
the cleaning solution may be controlled so that the concentration
of the alkanol amine becomes at least 10 wt % or more. When the
concentration of the alkanol amine is less than 10 wt %, the
removal efficiency of the chloride ion is low, such that it may be
difficult to expect the high removal efficiency of impurities.
[0035] Meanwhile, the surface treating of the metal nano particles
110 (S120) may further include heating a mixing solution prepared
by adding the cleaning solution to the metal nano particles 110 at
a predetermined temperature. The heating temperature of the mixing
solution may be approximately 60.degree. C. to 100.degree. C. In
particular, when the alcohol is added to the mixing solution, the
heating temperature of the mixing solution may be higher than
78.degree. C. that is a boiling point of the alcohol. However, a
substitution reaction between the alkanol amine 130 and the
chloride ion may be performed without heating the mixing solution,
such that the heating of the mixing solution may be optionally
performed.
[0036] Further, the metal nano particles 110 may be dried (S130).
The drying of the metal nano particles 110 may be for removing the
alkanol amine 130 adhered on the surfaces of the metal nano
particles 110. The drying of the metal nano particles 110 may
include the heat treating of the metal nano particles 110 at a
temperature of at least 50.degree. C. or more. Therefore, the
alkanol amine 130 adhered to the metal nano particles 110 is dried
and removed, such that the metal nano particles 110 having chloride
ion concentration less than approximately 100 ppm can be obtained.
In particular, the method for surface treating metal nano particles
according to the exemplary embodiment of the present invention can
obtain the high-purity metal nano particles 110 having the chloride
ion concentration of approximately 10 ppm or less, more preferably,
less than 5 ppm.
EXAMPLE 1
[0037] After the metal nano particles were synthesized, the
synthesized metal nano particles were each cleaned with ethanol
twice and toluene twice, respectively and were added to a cleaning
solution formed of triethanol amine and ethanol to prepare the
mixing solution. The mixing solution was heated at a temperature of
80.degree. C. Further, after the metal nano particles were dried,
the amount of chloride ion remaining on the surfaces of the nano
particles was analyzed using ion chromatography. The following
Table 1 shows the removal effect of chloride ion over the surface
treating time of a triethanol amine containing solution as
described above.
TABLE-US-00001 TABLE 1 Chloride Ion Division Concentration (ppm)
Prior to surface treating 1780 with alkanol amine After 30 minutes
of surface 5.6 treating with alkanol amine After 10 hours of
surface 2.3 treating with alkanol amine
[0038] As described above, the final chloride ion concentration of
the metal nano particles which are surface treated with the alkanol
amine containing cleaning solution shown the removal ratio of 99%
or more than that of the first metal nano particles. That is, the
alkanol amine containing cleaning solution may show the removal
ration of the high chloride ion of the metal nano particles only by
the surface treatment for a short time of about 30 minutes, such
that it was shown that the manufacturing process yield of the nano
particles having high purity may be significantly improved. In
particular, the chloride ion concentration of the metal nano
particles may be reduced less than 10 ppm only with the surface
treating of 30 minutes and the chloride ion concentration may be
reduced less than 5 ppm.
[0039] As described above, the method for surface treating metal
nano particles according to the exemplary embodiment of the present
invention can effectively remove the chloride ion that is difficult
to be relatively removed among the impurities 120 adhered on the
surface of the synthesized metal nano particles 110 with the
alkanol amine solution. In particular, the exemplary embodiment of
the present invention may remove the chloride ion of 99% or more
within the relatively short process time, thereby significantly
improving the surface treating processing efficiency. Therefore,
the method for surface treating metal nano particles to the
exemplary embodiment of the present invention surface-treats the
synthesized metal nano particles by using the alkanol amine
solution to effectively remove the chloride ion that is difficult
to be relatively removed among the impurities remaining on the
surfaces of the synthesized metal nano particles, thereby obtaining
the high-purity metal nano particles having the chloride ion
concentration of approximately 100 ppm, preferably, less than 5
ppm.
[0040] To be continued, as described above, various applications of
the metal nano particles 110 from which the impurities are removed
by the surface treating method according to the exemplary
embodiment of the present invention will be described in
detail.
[0041] The surface-treated metal nano particles according to the
exemplary embodiment of the present invention may be used as a
material for forming internal wirings of the electronic circuit. In
particular, in the case in which the metal nano particles are
nickel nano particles, the nickel nano particles have the
relatively higher purity and tap density and thus, may be suitably
used as a material for forming the electrode of the multi-layer
ceramic capacitor (MLCC) that is gradually small and thin in
recent.
[0042] FIG. 3 is a diagram illustrating a multi-layer ceramic
capacitor manufactured by using nickel nano particles to which the
method for surface treating metal nano particles according to the
exemplary embodiment of the present invention is applied. Referring
to FIG. 3, a nickel paste may be prepared by adding an organic
binder and an organic solvent to the nickel nano particles obtained
by synthesizing the nickel nano particles and performing the
surface treating described with reference to FIGS. 1 and 2 on the
synthesized nickel nano particles. An example of the organic binder
may include ethyl cellulose, and the like, and an example of the
organic solvent may include terpineol, dihydroxy terpineol,
1-octanol kerosene, and the like. In this case, the contents of the
nickel paste may be controlled to have 40 wt % to 60 wt % of nickel
nano particles, 0.8 wt % to 4 wt % of organic binder, and 40 wt %
to 60 wt % of organic solvent. Here, the conductive paste according
to the exemplary embodiment of the present invention may further
include any one additives among a plasticizer, an anti-viscosity
agent, and a dispersant.
[0043] Further, after the plurality of dielectric sheets 20 are
prepared, predetermined internal electrodes 30 of the metal paste
may be formed on each dielectric sheets 20 by a screen printing
method. The dielectric sheets 20 are laminated and burned, thereby
manufacturing the laminate 40. External electrodes 50 electrically
connected with the internal electrodes 30 may be formed at both
ends of the laminate 40. In this case, the external electrode 50
may be formed using the nickel paste. When the external electrode
50 is formed of the nickel paste, a separate plating process for
forming the external electrode 50 may not be performed. The
multi-layer ceramic capacitor 10 having the high electrode
characteristics may be manufactured by the foregoing process.
[0044] The foregoing exemplary embodiment of the present invention
describe, by way of example, the case in which the metal nano
particles according to the present invention are applied to the
chip component elements such as the multi-layer ceramic capacitor,
but the metal nano particles according to the present invention can
be applied to various fields. As another example, the metal nano
particles may be used as a catalyst. In more detail, the metal nano
particles may be used as a catalyst for a fuel cell, a
hydrogenation catalyst, a substitute catalyst of Pt in various
chemical reactions, and the like.
[0045] According to the exemplary embodiments of the present
invention, the chloride ion impurities that are difficult to be
relatively removed are treated with the alkanol amine solution so
as to effectively remove the chloride ion impurities, thereby
obtaining the metal nano particles having the high purity.
[0046] According to the exemplary embodiments of the present
invention, the method for surface treating metal nano particles
surface-treats the synthesized metal nano particles by using the
alkanol amine solution to effectively remove the chloride ion that
is difficult to be relatively removed among the impurities
remaining on the surfaces of the synthesized metal nano particles,
thereby obtaining the metal nano particles having high purity.
[0047] The above detailed description exemplifies the present
invention. Further, the above contents just illustrate and describe
preferred embodiments of the present invention and the present
invention can be used under various combinations, changes, and
environments. That is, it will be appreciated by those skilled in
the art that substitutions, modifications and changes may be made
in these embodiments without departing from the principles and
spirit of the general inventive concept, the scope of which is
defined in the appended claims and their equivalents. Although the
exemplary embodiments of the present invention have been disclosed
for illustrative purposes, those skilled in the art will appreciate
that various modifications, additions and substitutions are
possible, without departing from the scope and spirit of the
invention as disclosed in the accompanying claims. Therefore, the
detailed description of the present invention does not intend to
limit the present invention to the disclosed embodiments. Further,
it should be appreciated that the appended claims include even
another embodiment.
* * * * *