KR101792322B1 - Surface-treated metal powder and manufacturing method therefor - Google Patents

Abstract

A surface-treated metal powder having excellent sintering retardancy, which can be preferably used for manufacturing an electrode for a chip-laminated ceramic capacitor, is coated on a surface of a metal powder having an adhesion amount of at least one of Si, Ti, Al, Zr, 200 to 16000 占 퐂, and a surface treated metal powder having a weight percentage of N relative to metal powder of 0.02% or more.

Description

TECHNICAL FIELD [0001] The present invention relates to a surface-treated metal powder, and a method of manufacturing the same. BACKGROUND ART [0002]

TECHNICAL FIELD The present invention relates to a surface-treated metal powder suitable for manufacturing an electrode for a chip-laminated ceramic capacitor, and a manufacturing method thereof.

Chip multilayer ceramic capacitors are electronic components used in many electronic equipment because of their small size and large capacity. The chip multilayer ceramic capacitor has a structure in which a ceramic dielectric and internal electrodes are stacked and integrated to form a capacitor element. Each of the stacked layers constitutes a capacitor element, and these elements are electrically connected in parallel to each other by an external electrode, And is a compact and large-capacity capacitor.

In the production of a chip multilayer ceramic capacitor, a dielectric sheet is produced as follows. That is, first, an organic binder and a solvent are added to a dielectric material powder such as BaTiO ₃ or the like as a dispersant or a molding aid, and the mixture is subjected to pulverization, mixing and defoaming to obtain a slurry. Thereafter, the slurry is spread on the carrier film such as a PET film by a coating method such as a die coater. And dried to obtain a thin dielectric sheet (green sheet).

On the other hand, as in the case of the dielectric material powder, the metal powder as the raw material of the internal electrode of the chip multilayer ceramic capacitor is mixed with the organic binder and the solvent as a dispersant, a molding aid, and a defoaming process to obtain a slurry. The inner electrode is printed and dried mainly on a green sheet (dielectric sheet) by a screen printing method, then the printed green sheet is peeled off from the carrier film, and a large number of such green sheets are laminated.

A press pressure of several tens to several hundreds of MPa is applied to the laminated green sheets in this way to integrate them, and then they are cut into individual chips. Thereafter, the internal electrode layer and the dielectric layer are sintered at a high temperature of about 1000 캜 in the firing furnace. Thus, a chip multilayer ceramic capacitor is produced.

In this chip multilayer ceramic capacitor, Pt was used at the time when the technology was developed, but Pd, Pd-Ag alloy and Ni are mainly used from the viewpoint of cost. However, recently, it has been required to replace Ni with Cu in view of environmental regulations. If Ni is replaced with Cu, in principle, low inductance can be realized for high frequency applications. Cu also has the advantage of being cheaper than Ni.

On the other hand, with the miniaturization of the capacitor, the internal electrode tends to be thinned, and in the next generation type, it is known that it is about 1 탆. For this reason, it has been desired that the particle size of the internal electrode powder is further reduced.

However, the melting point of Cu is originally lower than that of Pt, Pd and Ni. In addition, when Cu is employed as the internal electrode powder due to the lowering of the melting point caused by the increase of the surface area due to the small-sized curing of particles as described above, melting of the Cu component starts at a lower temperature during firing. This causes generation of cracks in the electrode layer itself. Further, since the electrode layer shrinks sharply after the temperature is lowered, delamination of the dielectric layer and the electrode layer may occur. In order to avoid such a problem, the internal electrode metal powder is required to have a heat shrinkage characteristic equivalent to that of a dielectric, and there is a sintering start temperature as an index to indicate this.

With respect to this demand, a method of performing surface treatment on Cu powder has been proposed so far to obtain a Cu powder suitable for the internal electrode of the chip multilayer ceramic capacitor.

Patent Document 1 (Japanese Patent No. 4001438) discloses a method in which a Cu component is dispersed in a solution, an aqueous solution of a water-soluble salt of a metal element is added thereto, and the pH is adjusted to fix the metal oxide to the surface of the Cu component, To strengthen the adhesion of the surface treatment layer. However, since the process consists of adsorption of a metal oxide on the copper alloy and strengthening of adhesion, there is a problem in terms of productivity. When the particle diameter of the copper powder is smaller than 0.5 占 퐉, it is expected that the adsorption of the oxide to the copper powder itself becomes difficult because the size of the copper oxide powder is close to the size of the metal oxide particle to be adsorbed.

Patent Document 2 (Japanese Patent No. 4164009) is a technique for coating a copper powder with a silicone oil having a specific functional group. However, since the oil and the Cu component are mixed, they easily aggregate and there is a problem in workability. Further, filtration at the time of separation of the oil and the Cu component is difficult, which causes a problem in workability.

Patent Document 3 (Japanese Patent No. 3646259) is a technique of polycondensation reaction of hydrolyzed alkoxysilane with an ammonia catalyst to form a SiO ₂ gel coating film. However, the particle size when applied to dongbun less than 1 ㎛, catalyst, because it is very difficult it depends on the skill workability and productivity of a specific operation function of the reaction control to be added continuously to the NH ₃ prevent aggregation added There is a problem in.

Patent Document 1: Japanese Patent Publication No. 4001438 Patent Document 2: Japanese Patent Publication No. 4164009 Patent Document 3: Japanese Patent Publication No. 3646259

As described above, there is a demand for copper that is excellent in sintering retardancy, workability, and productivity, which can be preferably used for the production of internal electrodes of a chip multilayer ceramic capacitor.

Therefore, an object of the present invention is to provide a surface-treated copper alloy having excellent sintering delayability which can be suitably used for manufacturing an electrode for a chip-laminated ceramic capacitor, and a method for producing the same.

The present inventors have intensively studied and found that by adsorbing aminosilane to the surface of a copper alloy by mixing the copper powder and an aqueous solution of aminosilane, aggregation after the surface treatment does not occur and the sintering retardancy is dramatically improved. This operation is very simple and does not require a high-level function, so that the workability is excellent and the productivity is excellent. In addition, the surface-treated copper powder thus obtained exhibited a high sintering initiation temperature in spite of the small particle size of the particles. It was also found that, even when the metal powders other than the copper powder were subjected to the same surface treatment, the surface treated metal powder having the same excellent properties was obtained even when the surface treatment was performed with a coupling agent other than aminosilane.

Therefore, the present invention is in the following (1) to (27).

(One)

A surface-treated coarse fraction having an adhesion amount of Si of 500 to 16000 占 퐂 per 1 g of the copper content, and a weight percentage of N relative to the copper content of not less than 0.05% and not more than 0.5%.

(2)

(1), wherein the adhesion amount of Si is 500 to 3000 占 퐂 per g of the copper content, and the weight percentage of N relative to the copper content is 0.05% or more and 0.5% or less.

(3)

(1) or (2), wherein the copper is a copper foil surface-treated with a silane coupling agent.

(4)

(3) wherein the silane coupling agent is an aminosilane.

(5)

(1) to (4) wherein the weight percentage of N relative to the copper content is in the range of 0.05% to 0.50%.

(6)

(1) to (5), in which N is removed by heat treatment.

(7)

(1) to (6) under an oxygen atmosphere or an inert atmosphere.

(8)

(1) to (7), wherein the sintering initiation temperature is 400 占 폚 or higher.

(9)

(1) to (8), which is obtained by mixing an aqueous solution of aminosilane and a copper component, followed by stirring and drying.

(10)

(1) to (9), wherein the amount of the aminosilane to be provided to the surface treatment is 0.01 ml or more with respect to 1 g of the copper powder.

(11)

(10) wherein the amount of aminosilane is 0.05 ml or more, and mixing with the copper powder and stirring time is 30 minutes or less,

(12)

(1) to (11), wherein the aminosilane is a monoaminosilane or a diaminosilane.

(13)

Raw material copper The copper powder described in any of (1) to (12) obtained by the wet process.

(14)

(1) to (13), wherein D50? 1.5 占 퐉.

(15)

(1) to (13), wherein D50? 1.0 占 퐉.

(16)

(1) to (13), wherein D50? 0.5 占 퐉 and Dmax? 1.0 占 퐉.

(17)

(1) to (16) wherein the particle size distribution is monoclinic.

(18)

(1) to (17).

(19)

(1) to (17).

(20)

(1) to (19) is further subjected to a surface treatment with an organic compound.

(21)

A conductive paste using the copper powder according to any one of (1) to (20).

(22)

(21). ≪ RTI ID = 0.0 > 21. < / RTI >

(23)

The chip-laminated ceramic capacitor according to (22), wherein SiO ₂ having a diameter of 10 nm or more exists in the end face of the internal electrode.

(24)

The chip-laminated ceramic capacitor according to (22) or (23), wherein the cross-section of the internal electrode has SiO ₂ of 0.5 μm or more in maximum diameter at 0.5 number / cm 2 or less.

(25)

A multilayer substrate in which the chip multilayer ceramic capacitor described in any one of (22) to (24) is mounted on an outermost layer.

(26)

Layer substrate in which the chip-laminated ceramic capacitor described in any one of (22) to (24) is mounted on an inner layer.

(27)

(25) or (26).

The present invention is also described in the following (31) to (50).

(31)

And a step of mixing the copper powder with an aqueous aminosilane solution to prepare a copper powder dispersion.

(32)

The method according to (31), comprising a step of stirring the ferrous dispersion.

(33)

The method according to (31) or (32), which comprises a step of ultrasonic-treating the ferrofluid dispersion.

(34)

The method according to (33), wherein the step of ultrasonic treatment is a step of performing ultrasonic treatment for 1 to 180 minutes.

(35)

A step of filtering the dispersion of coarse powder to recover the coarse powder,

Filtering and recovering the recovered copper powder to obtain a surface-treated copper powder,

(31) to (34).

(36)

The method according to (35), wherein the drying is carried out by heat treatment at 50 to 90 占 폚 for 30 to 120 minutes.

(37)

The method according to (35) or (36), wherein the drying is performed in an oxygen atmosphere or an inert atmosphere.

(38)

The method according to any one of (31) to (37), wherein the copper dispersion contains 0.025 g or more of aminosilane with respect to 1 g of the copper powder.

(39)

Wherein the aqueous solution of aminosilane has the following formula I:

H ₂ N-R ¹ -Si (OR ² ) ₂ (R ³ ) (Formula I)

(In the above formula I,

R1 is a divalent group of a straight or branched saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, C1-C12 hydrocarbon having a heterocyclic ring or no heterocyclic ring,

R2 is a C1-C5 alkyl group,

R3 is a C1-C5 alkyl group or a C1-C5 alkoxy group.)

(31) to (38), wherein the aminosilane is an aqueous solution of aminosilane.

(40)

R1 is selected from the group consisting of substituted or unsubstituted divalent groups of C1 to C12 linear saturated hydrocarbons, substituted or unsubstituted C1 to C12 branched divalent groups of branched saturated hydrocarbons, substituted or unsubstituted C1 to C12 linear A substituted or unsubstituted C1 to C12 heterocyclic hydrocarbon, a substituted or unsubstituted C1 to C12 branched unsaturated hydrocarbon, a divalent of a C1 to C12 cyclic hydrocarbon, a substituted or unsubstituted C1 to C12 heterocyclic ring A substituted or unsubstituted divalent group of a C1-C12 aromatic hydrocarbon, a divalent group of a C1-C12 aromatic hydrocarbon, and the like.

(41)

R1 _{a, - (CH 2) n -} , - (CH 2) n - (CH) m - (CH 2) j-1 -, - (CH 2) n - (CC) - (CH 2) n-1 _{-, - (CH 2) n} -NH- (CH 2) m -, - (CH 2) n -NH- (CH 2) m -NH- (CH 2) j -, - (CH 2) n-1 _{- (CH) NH 2 - (} CH 2) m-1 -, - (CH 2) n-1 - (CH) NH 2 - group consisting of _{- (CH 2) m-1} -NH- (CH 2) j (Wherein n, m, and j are integers of 1 or more).

(42)

R1 _{a, - (CH 2) n -} , or _{- (CH 2) n -NH- (} CH 2) m - method according to item (39).

(43)

The method according to any one of (41) to (42), wherein n, m and j are each independently 1, 2 or 3.

(44)

The process according to any one of (39) to (43), wherein R 2 is a methyl group or an ethyl group.

(45)

The process according to any one of (39) to (44), wherein R 3 is a methyl group, an ethyl group, a methoxy group or an ethoxy group.

(46)

The method according to any one of (31) to (45), wherein the copper is a copper alloy powder produced by a wet method.

(47)

(31) to (46), with a solvent and / or a binder to produce a conductive copper paste.

(48)

(31) to (46), with a solvent and / or a binder to obtain a conductive copper paste;

A step of applying a conductive copper paste to a substrate,

A step of heating and firing the conductive copper paste applied to the substrate,

≪ / RTI >

(49)

Wherein the electrode is an electrode for a chip-laminated ceramic capacitor.

(50)

A step of further surface-treating the surface-treated copper powder with an organic compound,

(31) to (49).

The present invention is also described in the following (51) to (54).

(51)

(31) to (46).

(52)

(45). ≪ / RTI >

(53)

(46).

(54)

(47). ≪ RTI ID = 0.0 > (47) < / RTI >

The present invention is also described in the following (61) to (63).

(61)

(31) to (46), wherein the surface-

The adhesion amount of Si is 500 ~ 16000 占 퐂 per g of the copper content,

The weight percentage of N relative to the copper content is not less than 0.05% and not more than 0.5%

Sintering temperature of 400 ° C or higher.

(62)

And the surface-treated copper described in (61).

(63)

(62) is coated with an electrically conductive copper paste,

And an SiO ₂ having a maximum diameter of 0.5 탆 or more exists at 0.5 / cm 2 or less on the electrode cross section.

The present invention is also shown in the following (71).

(71)

Wherein at least one of Ti, Al, Zr, Ce, and Sn has an adhesion amount of 300 to 1500 占 퐂 per 1 g of the copper content, and a weight percentage of N relative to the metal content is 0.05% to 0.5%.

(72)

(71) in which Ti, Al, Zr, Ce and Sn are adsorbed by the coupling agent treatment.

(73)

(71) or (72), which is treated with a coupling agent whose molecular structure terminal is an amino group.

(74)

The coupling agent of (73) wherein the coupling agent is a titanate or aluminate coupling agent.

(75)

Wherein the amount of deposition of at least one of Ti, Al, Zr, Ce and Sn is 300 to 1500 占 퐂 per 1 g of the copper content, 0.05 to 0.5% by weight of N relative to the metal content, .

(76)

A metal powder other than surface-treated Cu having an adhesion amount of at least one of Si, Ti, Al, Zr, Ce and Sn of 200 to 1500 占 퐂 against 1 g of metal powder and N wt.% To metal powder of 0.02%

(77)

(71) in which the metal component is Pt, Pd, Ag, or Ni.

(78)

The metal powder of (76) or (77), wherein Si, Ti, Al, Zr, Ce and Sn are adsorbed by a coupling agent treatment.

(79)

The metal powder of (78), wherein the coupling agent is silane, titanate, or aluminate.

(80)

The metal powder of (79), which is treated with a coupling agent whose terminal is an amino group.

(81)

Wherein at least one of Si, Ti, Al, Zr, Ce, and Sn has an adhesion amount of 200 to 1,500 占 퐂 to 1 g of a metal powder other than Cu, a weight percentage of N to metal powders other than Cu is 0.02% Is not less than 400 캜.

(82)

(71) to (81) are mixed with the surface-treated metal powder.

(83)

(82) is coated with a conductive metal paste and heated and fired,

Wherein at least one of SiO ₂ , TiO ₂ and Al ₂ O ₃ having a maximum diameter of 0.5 μm or more is present at 0.5 electrode / μm ² or less on the electrode cross section.

The present invention is also shown in the following (101).

(101)

The surface-treated metal powder having an adhesion amount of at least one of Si, Ti, Al, Zr, Ce and Sn of 200 to 16000 占 퐂 per 1 g of metal powder and N wt.

(102)

A metal powder according to (101), wherein the metal component is any one of Pt, Pd, Ag, Ni, and Cu.

(103)

The metal powder according to (101), wherein the metal powder is a copper powder.

(104)

A metal powder according to (101), wherein the metal component is any one of Pt, Pd, Ag and Ni.

(105)

The metal powder according to any one of (101) to (104), wherein the adhesion amount of any one or more of Si, Ti, Al, Zr, Ce and Sn is 300 to 16000 g per 1 g of metal powder.

(106)

The metal powder according to any one of (101) to (104), wherein the adhesion amount of at least one of Si, Ti, Al, Zr, Ce and Sn is 500 to 16000 g per 1 g of metal powder.

(107)

The metal powder according to any one of (101) to (106), wherein the adhesion amount of any one or more of Si, Ti, Al, Zr, Ce and Sn is not more than 3000 쨉 g per 1 g metal powder.

(108)

The metal powder according to any one of (101) to (106), wherein the adhesion amount of any one or more of Si, Ti, Al, Zr, Ce and Sn is 1500 쨉 g or less per 1 g of the metal powder.

(109)

The metal powder according to any one of (101) to (108), wherein the weight percentage of N relative to the metal powder is 0.05% or more and 0.5% or less.

(110)

The metal powder according to any one of (101) to (109), wherein at least one of Si, Ti, Al, Zr, Ce and Sn is at least one of Ti, Al, Zr, Ce and Sn.

(111)

The metal powder according to any one of (101) to (109), wherein at least one of Si, Ti, Al, Zr, Ce and Sn is Si.

(112)

A metal powder according to (101), wherein the metal powder is a copper powder, the adhesion amount of Si is 500 to 16000 占 퐂 per 1 g of the copper powder, and the weight percentage of N to the copper powder is 0.05% to 0.5%.

(113)

The metal powder according to (101), wherein the metal powder is a copper powder, the adhesion amount of Si is 500 to 3000 占 퐂 per 1 g of the copper powder, and the weight percentage of N to the copper powder is 0.05% to 0.5%.

(114)

The metal powder according to any one of (101) to (113), wherein the metal powder is a metal powder surface-treated with a coupling agent.

(115)

The metal powder according to any one of (101) to (114), wherein at least one of Si, Ti, Al, Zr, Ce and Sn is adsorbed by a coupling agent treatment.

(116)

The metal powder according to any one of (101) to (115), wherein the coupling agent is any one of silane, titanate and aluminate.

(117)

The metal powder according to any one of (101) to (116), wherein the coupling agent is a coupling agent whose terminal is an amino group.

(118)

The metal powder according to any one of (101) to (117), wherein the coupling agent is aminosilane.

(119)

The metal powder according to any one of (101) to (118), wherein the sintering initiation temperature is 400 占 폚 or higher.

(120)

The metal powder according to (118), wherein the aminosilane is a monoaminosilane or a diaminosilane.

(121)

(101) to (120) are further surface-treated with an organic compound.

(122)

Wherein the amount of one or more of Si, Ti, Al, Zr, Ce, and Sn is 200 to 1500 占 퐂 per gram of the metal powder other than Cu; , And the sintering initiation temperature is 400 占 폚 or higher.

(123)

Conductive metal powder paste using the metal powder according to any one of (101) to (122).

(124)

(123) is coated with a conductive metal paste and heated and fired,

Wherein at least one of SiO ₂ , TiO ₂ and Al ₂ O ₃ having a maximum diameter of 0.5 μm or more is present at 0.5 electrode / μm ² or less on the electrode cross section.

(125)

(123). ≪ / RTI >

(126)

The chip-laminated ceramic capacitor according to (125), wherein SiO ₂ , TiO ₂ or Al ₂ O ₃ having a diameter of 10 nm or more exists in the end face of the internal electrode.

(127)

(125) or (126), wherein SiO ₂ , TiO ₂ or Al ₂ O ₃ having a maximum diameter of 0.5 μm or more exists at 0.5 number / μm ² or less on the cross section of the internal electrode.

(128)

Layered ceramic capacitor according to any one of (125) to (127) is mounted on the outermost layer.

(129)

Layered ceramic capacitor according to any one of (125) to (127) is mounted on an inner layer.

(130)

(128) or (129).

(131)

A method for producing a surface-treated metal powder, comprising the step of mixing a metal powder with an aqueous solution of a coupling agent to prepare a metal powder dispersion.

(132)

The method according to (131), wherein the metal component is any one of Pt, Pd, Ag, Ni, and Cu.

(133)

The method according to (131), wherein the metal component is a copper component.

(134)

The method according to (131), wherein the metal component is one of Pt, Pd, Ag, and Ni.

(135)

A method according to any one of (131) to (134), which comprises a step of stirring the metal powder dispersion.

(136)

The method according to any one of (131) to (135), which comprises a step of ultrasonically treating a metal powder dispersion.

(137)

The method according to any one of (131) to (136), wherein the step of ultrasonic treatment is a step of performing ultrasonic treatment for 1 to 180 minutes.

(138)

A step of filtering the metal powder dispersion to recover the copper powder,

Filtering and recovering the recovered copper powder to obtain a surface-treated metal powder,

(131) to (137).

(139)

The method according to (138), wherein the drying is performed in an oxygen atmosphere or an inert atmosphere.

(140)

The method according to any one of (131) to (139), wherein the metal powder dispersion liquid contains 0.025 g or more of a coupling agent per 1 g of metal powder.

(141)

Wherein the aqueous coupling agent solution has the following formula I:

H ₂ N-R ¹ -Si (OR ² ) ₂ (R ³ ) (Formula I)

(In the above formula I,

R1 is a divalent group of a straight or branched saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, C1-C12 hydrocarbon having a heterocyclic ring or no heterocyclic ring,

R2 is a C1-C5 alkyl group,

R3 is a C1-C5 alkyl group or a C1-C5 alkoxy group.)

To (140), wherein the aminosilane is an aqueous solution of aminosilane represented by the following formula (1).

(142)

R1 _{a, - (CH 2) n -} , - (CH 2) n - (CH) m - (CH 2) j-1 -, - (CH 2) n - (CC) - (CH 2) n-1 _{-, - (CH 2) n} -NH- (CH 2) m -, - (CH 2) n -NH- (CH 2) m -NH- (CH 2) j -, - (CH 2) n-1 _{- (CH) NH 2 - (} CH 2) m-1 -, - (CH 2) n-1 - (CH) NH 2 - group consisting of _{- (CH 2) m-1} -NH- (CH 2) j (Wherein n, m, and j are integers of 1 or more).

(143)

Wherein the aqueous coupling agent solution satisfies the following formula II:

(H ₂ N-R ¹ -O) _p Ti (OR ² ) _q (Formula II)

(Provided that in the above formula (II)

R1 is a divalent group of a straight or branched saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, C1-C12 hydrocarbon having a heterocyclic ring or no heterocyclic ring,

R2 is a linear or branched C1 to C5 alkyl group,

p and q are integers of 1 to 3, and p + q = 4.

To (140), wherein the aqueous solution of an amino group-containing titanate represented by the following formula (1) is used.

(144)

R1 _{a, - (CH 2) n -} , - (CH 2) n - (CH) m - (CH 2) j-1 -, - (CH 2) n - (CC) - (CH 2) n-1 _{-, - (CH 2) n} -NH- (CH 2) m -, - (CH 2) n -NH- (CH 2) m -NH- (CH 2) j -, - (CH 2) n-1 _{- (CH) NH 2 - (} CH 2) m-1 -, - (CH 2) n-1 - (CH) NH 2 - group consisting of _{- (CH 2) m-1} -NH- (CH 2) j (Wherein n, m, and j are integers of 1 or more).

(145)

The method according to any one of (131) to (144), wherein the metal powder is a copper powder produced by a wet process.

(146)

A method for producing a conductive metal powder paste by mixing a surface-treated metal powder produced by the production method described in any one of (131) to (145) with a solvent and / or a binder.

(147)

A step of mixing the surface-treated metal powder produced by the production method described in any one of (131) to (145) with a solvent and / or a binder to obtain a conductive metal powder paste,

A step of applying a conductive metal powder paste to a substrate,

A step of heating and firing the conductive metal powder paste applied to the substrate,

≪ / RTI >

(148)

A surface-treated metal powder produced by the manufacturing method according to any one of (131) to (145).

(149)

(146). ≪ / RTI >

(150)

(147). ≪ / RTI >

(151)

The surface-treated metal powder produced by the production method according to any one of (131) to (145)

The deposition amount of any of Si, Ti and Al is 200 to 16000 占 퐂 per 1 g of the metal powder,

The weight percentage of N relative to the metal powder is 0.02% or more,

A metal powder having a sintering initiation temperature of 400 ° C or higher.

(152)

Treated metal powder described in (151).

(153)

(151) is coated with a conductive metal powder paste and heated and fired,

Wherein at least one of SiO ₂ , TiO _2, and Al ₂ O ₃ having a maximum diameter of 0.5 탆 or more is present at 0.5 or less / ² 탆 on the electrode surface.

The surface-treated copper powder according to the present invention does not agglomerate even after the surface treatment, exhibits excellent sintering retardancy, and exhibits a high sintering initiation temperature even if the particles are small in number. Therefore, when the conductive copper paste in which the surface-treated copper according to the present invention is blended is used, manufacturing problems such as electrode peeling can be avoided and the electrode for a chip multilayer ceramic capacitor can be advantageously produced. The surface-treated copper powder according to the present invention can be produced by subjecting the copper powder to a very simple treatment, and this production method does not require a high-level function and is excellent in workability and productivity. Further, according to the present invention, the metal powder other than the copper powder has the same excellent properties

1 is a TEM image of a cross-section of a sintered body obtained from a surface-treated copper powder.

Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the specific embodiments mentioned below.

In the present invention, the step of mixing the copper powder with the aqueous solution of aminosilane to prepare the copper powder dispersion is carried out, and the copper powder subjected to surface treatment from the copper powder dispersion can be obtained.

As the copper powder to be provided in the surface treatment, a copper powder produced by a known method can be used. For example, the copper powder may be a copper powder produced by the dry process or a copper powder produced by the wet process. The copper powder produced by the wet process is preferable in that the wet process is consistently performed by combining the surface treatment according to the present invention.

The aqueous solution of aminosilane is an aqueous solution of aminosilane which can be used as a silane coupling agent. In a preferred embodiment, the amount of aminosilane to be used is 0.025 g or more, preferably 0.050 g or more, more preferably 0.075 g or more, and even more preferably 0.050 g or more, with respect to 1 g of the copper Or 0.10 g or more, or may contain, for example, an amount ranging from 0.025 to 0.500 g, 0.025 to 0.250 g, and 0.025 to 0.100 g. In a preferred embodiment, the amount of the aminosilane to be used is 0.01 ml or more, 0.025 ml or more, preferably 0.050 ml or more, more preferably 0.050 ml or more, More preferably not less than 0.075 ml, more preferably not less than 0.10 ml, or it may contain, for example, an amount ranging from 0.025 to 0.500 ml, 0.025 to 0.250 ml, 0.025 to 0.100 ml .

In a preferred embodiment, a silane containing at least one amino group and / or an imino group as the aminosilane can be used. The number of amino groups and imino groups contained in the aminosilane may be, for example, 1 to 4, preferably 1 to 3, more preferably 1 to 2, respectively. In a preferred embodiment, the number of amino groups and imino groups contained in the aminosilane may be one each. The aminosilane having one amino group and the number of imino groups contained in the aminosilane is particularly monoaminosilane, the two aminosilanes are particularly diaminosilane, and the three aminosilanes are particularly called triaminosilane. Monoaminosilane and diaminosilane can be preferably used in the present invention. In a preferred embodiment, a monoaminosilane containing one amino group as the aminosilane can be used. In a preferred embodiment, the aminosilane can comprise at least one amino group, for example, one amino group at the end of the molecule, preferably at the end of a straight chain or branched chain-like molecule.

Examples of the aminosilane include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, Silane, 1-aminopropyltrimethoxysilane, 2-aminopropyltrimethoxysilane, 1,2-diaminopropyltrimethoxysilane, 3-amino-1-propenyltrimethoxysilane, Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl- (Vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, And 3- (N-phenyl) aminopropyltrimethoxysilane.

In a preferred embodiment, the aminosilane represented by the following formula I can be used.

H ₂ N-R ¹ -Si (OR ² ) ₂ (R ³ ) (Formula I)

In the above Formula I,

R1 is a divalent group of a straight or branched saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, C1-C12 hydrocarbon having a heterocyclic ring or no heterocyclic ring,

R2 is a C1-C5 alkyl group,

R3 is a C1-C5 alkyl group or a C1-C5 alkoxy group.

In a preferred embodiment, R 1 of the formula I is a linear or branched saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, C1 to C12 hydrocarbon having a heterocyclic ring or no heterocyclic ring More preferably R1 is a substituted or unsubstituted divalent group of C1 to C12 linear saturated hydrocarbons, a substituted or unsubstituted C1 to C12 divalent group of branched saturated hydrocarbons, substituted or unsubstituted A divalent group of C1 to C12 linear unsaturated hydrocarbon, a substituted or unsubstituted divalent group of C1 to C12 branched unsaturated hydrocarbon, a substituted or unsubstituted divalent group of C1 to C12 cyclic hydrocarbon, A divalent group of C1-C12 heterocyclic hydrocarbon, a substituted or unsubstituted C1-C12 aromatic hydrocarbon, and a divalent group of C1-C12 aromatic hydrocarbon. In a preferred embodiment, R1 in the formula (I) is a divalent group of a C1 to C12, saturated or unsaturated, chain-like hydrocarbon, more preferably a divalent group in which the atoms at both terminals of the chain structure have a free valence. In a preferred embodiment, the carbon number of the divalent group can be, for example, C1 to C12, preferably C1 to C8, preferably C1 to C6, preferably C1 to C3.

In a preferred embodiment, R1 in the above formula (I) _{- (CH 2) n -,} - (CH 2) n - (CH) m - (CH 2) j-1 -, - (CH 2) n - (CC _{) - (CH 2) n-} 1 -, - (CH 2) n -NH- (CH 2) m -, - (CH 2) n -NH- (CH 2) m -NH- (CH 2) j - _{, - (CH 2) n-} 1 - (CH) NH 2 - (CH 2) m-1 -, - (CH 2) n-1 - (CH) NH 2 - (CH 2) m-1 -NH- (CH ₂ ) _j - (provided that n, m, and j are integers of 1 or more). (CH ₂ ) _n - or - (CH ₂ ) _n --NH-- (CH ₂ ) _m -, wherein R 1 is - (CH ₂ ) _n - . (CC) represents a triple bond of C and C. In a preferred embodiment, the hydrogen of R1 as the bivalent group may be substituted with an amino group, for example, 1 to 3 hydrogens, for example, For example, one to two hydrogens, for example, one hydrogen may be substituted by an amino group.

In a preferred embodiment, each of n, m and j in formula (I) is independently an integer of 1 to 12, preferably an integer of 1 to 6, more preferably an integer of 1 to 4 For example, an integer selected from 1, 2, 3, and 4, and can be, for example, 1, 2, or 3.

In a preferred embodiment, R2 in formula (I) may be a C1 to C5 alkyl group, preferably a C1 to C3 alkyl group, more preferably a C1 to C2 alkyl group, and includes, for example, a methyl group, A propyl group, or a propyl group, preferably a methyl group or an ethyl group.

In a preferred embodiment, R3 in the formula (I) may be an alkyl group of C1 to C5, preferably a C1 to C3 alkyl group, more preferably a C1 to C2 alkyl group as an alkyl group and includes, for example, , An isopropyl group, or a propyl group, preferably a methyl group or an ethyl group. The R3 in the formula (I) may be an alkoxy group of C1 to C5, preferably an alkoxy group of C1 to C3, more preferably a C1 to C2 alkoxy group as the alkoxy group, and examples thereof include a methoxy group, An isopropoxy group, or a propoxy group, preferably a methoxy group or an ethoxy group.

The aqueous aminosilane solution can be mixed with the copper by a known method. At the time of mixing, stirring can be carried out by appropriately known methods. In a preferred embodiment, the mixing can be carried out at room temperature, for example, at a temperature in the range of 5 to 80 DEG C, 10 to 40 DEG C, 20 to 30 DEG C, for example.

In a preferred embodiment, the ferrous dispersion can be mixed and subjected to ultrasonic treatment. The treatment time of the ultrasonic treatment is selected depending on the state of the dispersion of the concentrate, but is preferably 1 to 180 minutes, more preferably 3 to 150 minutes, further preferably 10 to 120 minutes, further preferably 20 to 80 minutes .

In a preferred embodiment, the ultrasonic treatment can be carried out at an output of 100 ml, preferably 50 to 600 W, more preferably 100 to 600 W. In a preferred embodiment, the ultrasonic treatment is preferably carried out at a frequency of 10 to 1 MHz, more preferably 20 to 1 MHz, and more preferably 50 to 1 MHz.

The copper powder in the ferrofluid dispersion can be recovered as the surface-treated copper powder which has been subjected to the surface treatment with aminosilane and separated from the dispersion liquid as described above. For separation and recovery, known means can be used. For example, filtration, centrifugation, decantation, or the like can be used. Following the number of times of separation, drying may be carried out as desired. Drying can be carried out by known means, for example, by drying by heating. The heat drying can be carried out, for example, at a temperature of 50 to 90 캜 and 60 to 80 캜, for example, for 30 to 120 minutes and for 45 to 90 minutes. After the heating and drying, the crushing may be further carried out according to a desired manner. The recovered surface-treated copper fractions may be adsorbed on the surface of the surface treated copper fractions, for example, for the purpose of anti-rusting or improving the dispersibility in the paste.

As described above, in the preferred embodiment, the copper powder to be subjected to the surface treatment may be a copper powder by a wet method. In a preferred embodiment of the present invention, as a method for producing a copper alloy powder by a wet process, a process for producing a slurry by adding copper oxide in an aqueous solvent containing an additive for gum arabic, a process for adding dilute sulfuric acid to the slurry at a time within 5 seconds, A ferroelectric material produced by a method including a step of performing a reaction can be used. In a preferred embodiment, the slurry is maintained at room temperature (20 to 25 ° C) or lower, and dilute sulfuric acid maintained at room temperature or lower may be added to achieve disproportionation. In a preferred embodiment, the slurry is maintained at 7 DEG C or lower, and at the same time diluted sulfuric acid maintained at 7 DEG C or lower can be added to achieve disproportionation. In a preferred embodiment, the addition of diluted sulfuric acid can be added to a pH of 2.5 or less, preferably pH 2.0 or less, more preferably pH 1.5 or less. In a preferred embodiment, the addition of diluted sulfuric acid to the slurry is effected so that the addition of dilute sulfuric acid is within 5 minutes, preferably within 1 minute, more preferably within 30 seconds, more preferably within 10 seconds, and even more preferably within 5 seconds Can be added. In a preferred embodiment, the disproportionation reaction can be terminated in 10 minutes. In a preferred embodiment, the concentration of the gum arabic in the slurry may be from 0.229 to 1.143 g / L. As the copper oxide, copper oxide, preferably copper oxide, used in a known method can be used. The particle size of the copper oxide particles is not directly related to the grain size of the copper oxide particles produced by the disproportionation reaction Therefore, it is possible to use coarse copper oxide particles. The principle of this disproportionation reaction is as follows:

Cu ₂ O + H ₂ SO ₄ → Cu ↓ + CuSO ₄ + H ₂ O

The copper fractions obtained by this disproportionation may be washed, rust-inhibited, filtered, dried, crushed and classified according to the desire and then mixed with the aminosilane as desired. In a preferred embodiment, After filtration, it can be mixed with the aqueous aminosilane solution without drying.

In a preferred embodiment, the copper powder obtained by the disproportionation reaction has an average particle diameter of 0.25 탆 or less as measured by a laser diffraction particle size distribution measuring apparatus. In a preferred embodiment, the dynamic fractions obtained by the disproportionation reaction are such that D10, D90, and Dmax measured by a laser diffraction particle size distribution measuring apparatus are [Dmax D50 3, D90 D50 2, 0.5], and the distribution of particle diameters has a single peak. In a preferred embodiment, the fractions obtained by the disproportionation reaction have a single particle size distribution (with a single peak) as measured by a laser diffraction particle size distribution analyzer. In a preferred embodiment, the value measured by the laser diffraction type particle size distribution measuring apparatus is [D50? 1.5 占 퐉], preferably? D50? 1.0 占 퐉, more preferably [D50? 0.5 占 퐉, Dmax? 1.0 탆]. As the laser diffraction particle size distribution measuring apparatus, for example, SALD-2100 manufactured by Shimadzu Corporation can be used.

The surface-treated copper powder obtained by the present invention has excellent sintering retardancy. There is a sintering initiation temperature as an index of sintering retardancy. This is a temperature when a certain volume change (contraction) occurs by raising the green compact made of metal powder in a reducing atmosphere. In the present invention, the temperature at which 1% volume shrinkage occurs is defined as the sintering initiation temperature. Specifically, the measurement was performed as described in the examples. A higher sintering initiation temperature means that the sintering retardancy is excellent.

In a preferred embodiment, the sintering initiation temperature of the surface treated active ingredient according to the present invention is 450 DEG C or higher, preferably 500 DEG C or higher, more preferably 600 DEG C or higher, further preferably 700 DEG C or higher, More preferably 800 ° C or higher, still more preferably 810 ° C or higher, further preferably 840 ° C or higher, further preferably 900 ° C or higher, further preferably 920 ° C or higher, further preferably 950 ° C Or more. As compared with the case where the sintering initiation temperature of the ultrafine Ni powder (average particle diameter of 0.2 to 0.4 占 퐉) used in the case where a high sintering initiation temperature is required is in the range of 500 to 600 占 폚, The copper powder is made of Cu which is cheaper and obtainable than Ni, and has finer particles and superior sintering retardancy which is equal to or higher than that of Ni.

In a preferred embodiment, the surface-treated copper powder according to the present invention can form a sintered body by heating the green compact in a reducing atmosphere. The obtained sintered body is formed as an excellent electrode. This sintering process can be suitably used particularly in the production of internal electrodes of a chip multilayer ceramic capacitor. This sintered body can be preferably used particularly as an internal electrode of a chip multilayer ceramic capacitor. In a preferred embodiment, the sintered body may have SiO ₂ , preferably having a diameter of 10 nm or more, in its cross section. In a preferred embodiment, the sintered product in its cross-section, up to a diameter of more than 0.5 ㎛ SiO ₂ or may be made in the presence of ² or less 0.5 number / ㎛, or for example a maximum diameter of more than 0.5 ㎛ SiO ₂ is 0.0 to in the range 0.5 number / ㎛ ^2, for example a maximum diameter of more than 0.5 ㎛ SiO ₂ may be present in the range of 0.1 to 0.5 pieces / ㎛ ^2. This maximum diameter refers to the minimum circumscribed circle diameter of the SiO ₂ particles. In a preferred embodiment of the present invention, precipitation of the SiO ₂ particles is controlled in this manner, which makes it possible to form a very thin electrode, and at the same time, does not lower the reliability (quality) of the electrode.

In a preferred embodiment, the surface-treated copper powder may have an adhesion amount of Si of generally 500 to 16000 占 퐂, preferably 500 to 3000 占 퐂, per 1 g of the copper content. This Si deposition amount can be obtained by ICP (inductively coupled plasma atomic emission spectrometry). In a preferred embodiment, it is further possible to contain not less than 0.05 wt% and not more than 0.5 wt% of N relative to the weight of the active ingredient. The mechanism by which the silane coupling agent is adsorbed to the copper powder is unclear, but the present inventor believes that the adsorption occurs due to the interaction between nitrogen of the amino group at the end of the silane coupling agent and copper.

In a preferred embodiment, the surface-treated copper powder has a thickness (Si thickness) of the Si-containing layer formed by surface treatment of generally 0.6 to 25 nm, preferably 1.0 to 25 nm, more preferably 1.5 to 20 nm . The thickness (Si thickness) of the Si-containing layer in the present invention is measured by EDS (energy dispersive X-ray analysis) on the cross section of the surface of the surface treated copper powder, And the abundance ratio of Si atoms is 10% or more when the abundance ratio of Si atoms at the depth where the abundance ratio becomes maximum is 100%. The cross section of the surface of the surface treated copper powder was selected by selecting five out of at least 100 copper powder particles observed in the sample slice and treating the most clear boundary as a cross section perpendicular to the surface of the surface treated copper powder And aggregation can be performed.

In a preferred embodiment, the surface treated active ingredient may have a weight percentage of N relative to the active ingredient of, for example, 0.05 wt% or more, preferably 0.06 wt% or more, more preferably 0.07 wt% or more, In the range of 0.05 to 0.50% by weight, preferably 0.06 to 0.45% by weight, more preferably 0.08 to 0.40% by weight. The weight percent of N relative to the fines can be calculated by melting the fines at high temperatures and from the generated NO ₂ .

In a preferred embodiment, the surface treated copper powder has a surface N of, for example, not less than 1.0%, preferably not less than 1.4%, more preferably not less than 1.5%, as measured by XPS (X-ray photoelectron spectroscopy) , More preferably 1.6% or more, for example, 1.0 to 6.0%, preferably 1.4 to 6.0%, more preferably 1.5 to 6.0%, and furthermore preferably 1.6 to 6.0% For example, 1000 cps (count per second) or more, preferably 1200 cps or more, or for example, 1000 to 9000 cps, preferably 1200 to 8000 cps.

In a preferred embodiment, the surface treated copper powder has a surface Si content of, for example, not less than 0.6%, preferably not less than 0.8%, more preferably not less than 1.0%, as measured by XPS (X-ray photoelectron spectroscopy) , More preferably not less than 1.1%, further preferably not less than 1.2%, more preferably not less than 1.3%, further preferably not less than 1.4%, or for example, not less than 0.6% and not more than 4.0% , More preferably 1.0 to 4.0%, still more preferably 1.1 to 4.0%, still more preferably 1.2 to 4.0%, still more preferably 1.3 to 4.0%, still more preferably 1.4 to 4.0% of Si photoelectron, for example by irradiation (irradiation area 502655 ㎛ ²⁾ of the circle having a diameter of 800 ㎛, 1000 cps (count per second) , preferably at least, or for example, 1000 ~ 12000 1200 cps cps, preferably in the range of 1200 to 12000 cps. have.

In a preferred embodiment, the surface treated copper powder may be further subjected to a surface treatment after the surface treatment with aminosilane. Such surface treatment includes, for example, rust treatment with an organic rust inhibitor such as benzotriazole, imidazole, and the like, and the surface treatment with aminosilane is not eliminated even by such conventional treatment. Thus, to the extent that good sintering retardancy is not lost, those skilled in the art can carry out such known surface treatment as desired. That is, the copper obtained by subjecting the surface-treated copper powder according to the present invention to further surface treatment within the range of the present invention is also within the scope of the present invention as long as the excellent sintering retardancy is not lost.

In the present invention, even when a metal powder other than the copper powder is used, excellent characteristics can be obtained by the surface treatment described above for the copper powder. Even when a metal powder other than the copper powder is used, the present invention can be practiced by the preferred embodiments described above. As the metal powder, for example, metal powder of any one of Pt, Pd, Ag, Ni, and Cu can be used. Preferred metal components including the copper component include metal components of Ag, Ni, and Cu.

The present invention can be preferably carried out as described above by the attachment of Si, but can also be preferably carried out by attachment of an element other than Si. Even in the case where an element other than Si is attached, the present invention can be practiced by the preferred embodiments described above for Si. As the element other than Si, any one or more of Ti, Al, Zr, Ce, and Sn can be mentioned. As a preferable element including Si, any one or more of Si, Ti, Al, Zr, Ce and Sn, and more preferably at least one of Si, Ti and Al can be mentioned.

The present invention can be preferably carried out by surface treatment with a silane coupling agent as described above for the copper component, but it can also be preferably carried out by surface treatment with a coupling agent other than the silane coupling agent . Examples of the coupling agent other than the silane coupling agent include titanate and aluminate. When a silane coupling agent is used as the coupling agent, Si, Ti, and Al can be preferably adhered to each other when using Si, titanate, or aluminate, respectively. The mode of use of these coupling agents can be the same as described above for the silane coupling agent. Similar to the structure of the silane coupling agent, a structure in which a substituent containing an amino group at the terminal is coordinated to Ti and Al, which are central atoms, is also preferable in the structure of titanate and aluminate.

In a preferred embodiment, the preferable deposition amount of Si, Ti or Al by such a coupling agent is as described above for the copper content, and is preferably 200 to 16000 占 퐂, 300 to 16000 占 퐂 , For example, in the range of 500 to 16000 g, for example, 200 to 3000 g, 300 to 3000 g, and 500 to 3000 g, for example, 200 to 1500 g, 300 to 1500 g, .

In a preferred embodiment, the thickness (Si thickness) of the Si-containing layer formed by the surface treatment of the metal powder can be as described above in the same part, and the thickness of the Ti-containing layer (Ti thickness) Thickness) of the Si-containing layer can be made the same as described above with respect to the thickness (Si thickness) of the Si-containing layer.

In a preferred embodiment, the surface-treated metal powder can be subjected to a survey measurement of an XPS (X-ray photoelectron spectroscopy) analysis to make Si on the surface as described above for the copper powder. In addition to the Si adhered by the surface treatment, Ti and Al can be set to the same numerical range as the numerical range defined for Si by the same measurement method as Si.

In a preferred embodiment, the surface-treated metal powder can be subjected to a survey measurement of XPS (X-ray photoelectron spectroscopy) analysis to make N of the surface as described above for the copper portion.

As the titanate which can be preferably used in the present invention, the following formula II:

(H ₂ N-R ¹ -O) _p Ti (OR ² ) _q (Formula II)

(Provided that in the above formula (II)

R1 is a divalent group of a straight or branched saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, C1-C12 hydrocarbon having a heterocyclic ring or no heterocyclic ring,

R2 is a linear or branched C1 to C5 alkyl group,

p and q are integers of 1 to 3, and p + q = 4.

Containing amino group-containing titanate.

As the R 1 in the formula (II), the group represented by R 1 in the formula (I) can be preferably used. For example as R1 in the above formula _{Ⅱ, - (CH 2) n} -, - (CH 2) n - (CH) m - (CH 2) j-1 -, - (CH 2) n - (CC) - _{(CH 2) n-1 -} , - (CH 2) n -NH- (CH 2) m -, - (CH 2) n -NH- (CH 2) m -NH- (CH 2) j -, - _{(CH 2) n-1 -} (CH) NH 2 - (CH 2) m-1 -, - (CH 2) n-1 - (CH) NH 2 - (CH 2) m-1 -NH- (CH ₂ ) _j - (wherein n, m, and j are integers of 1 or more). Particularly preferred R 1 is - (CH ₂ ) _n -NH- (CH ₂ ) _m - (n + m = 4, particularly preferably n = m = 2).

As the R2 in the formula (II), the group represented by R2 in the formula (I) can be preferably used. In a preferred embodiment, the alkyl group of C3 may be mentioned, and particularly preferred are propyl group and isopropyl group.

P and q in the formula II are integers of 1 to 3 and p + q = 4, preferably a combination of p = q = 2, a combination of p = 3 and q = 1. As the amino group-containing titanate in which the functional group is arranged, Freenact KR44 (manufactured by Ajinomoto Fine Techno Co., Ltd.) can be mentioned.

The metal powder according to the present invention has a high sintering initiation temperature as described above as the copper powder according to the present invention and by blending it, an excellent conductive metal powder paste can be produced. By sintering the conductive metal powder paste, Can be manufactured. The sintering initiation temperature of the metal powder according to the present invention is as described above for the equivalent component. In a preferred embodiment, the electrode obtained by the present invention can be as described above for SiO ₂ on the end face of the electrode, and also for TiO _{2 on the end} face of the electrode and Al ₂ O ₃ on the end face of the electrode, The size, number, and density of SiO ₂ of the cross section can be set as described above. In a preferred embodiment, SiO ₂ of the electrode cross section corresponds to a case where a silane coupling agent is used as a coupling agent for the surface treatment, and when titanate is used as a coupling agent for surface treatment with respect to SiO ₂ of the electrode cross section And Al ₂ O ₃ of the electrode cross section corresponds to the case where aluminate is used as a coupling agent for surface treatment.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. The present invention is not limited to the following examples.

[Preparation of surface treated copper powder]

The surface-treated copper powder was prepared as follows.

[Milling by wet method]

20 g of the copper powder which was provided for the surface treatment was prepared by a wet process. The obtained copper powder had the following characteristics. The measurement was performed using a laser diffraction particle size distribution measuring apparatus (SALD-2100 manufactured by Shimadzu Corporation).

D50 0.12 탆

Distribution 1 Mountain

[Preparation of silane aqueous solution]

50 ml of each of the following silane aqueous solutions was prepared.

Silane: Diaminosilane A-1120 (manufactured by MOMENTIVE)

     Aminosilane A-1110 (manufactured by MOMENTIVE)

     Epoxy silane Z-6040 (manufactured by Toray Dow Corning)

     Methyltrimethoxysilane KBM-13 (manufactured by Shin-Etsu Silicone Co., Ltd.)

     3-phenylaminopropyltrimethoxysilane (MOMENTIVE)

The concentration was in the range of 0.5 to 15 vol%. In addition, except for the amino-based silane, the pH was adjusted to 4 with diluted sulfuric acid.

The structural formulas of various silanes are as follows.

Diamino silane A-1120:

H ₂ N-C ₂ H ₄ -NH-C ₃ H ₆ -Si (OCH ₃ ) ₃

Aminosilane A-1110:

H ₂ N-C ₃ H ₆ -Si (OCH ₃ ) ₃

Epoxy silane Z-6040:

Methyltrimethoxysilane KBM-13:

H ₃ C-Si (OCH ₃ ) ₃

3-phenylaminopropyltrimethoxysilane:

C ₆ H ₅ -NH-C ₃ H ₆ -Si (OCH ₃ ) ₃

[Surface treatment by mixing with silane aqueous solution]

(20 g) and each of the silane aqueous solutions (50 ml) were mixed and stirred to prepare a coarse dispersion, and the mixture was immediately subjected to ultrasonic treatment for 60 minutes (or 120 minutes) (manufactured by Techam Corp., ultrasonic cleaner 3 frequency type / W-113) 100 W, frequency 100 kHz). The time required for this 60 minutes is shown in Table 1 as mixing agitation time. The operation was carried out at room temperature.

In addition, as shown in Table 1, in some embodiments, stirring mixing (300 rpm) using a rotary blade was used together with the above ultrasonic stirring, or a silane coupling agent was adsorbed to the same by stirring with a rotary blade.

The ferrous dispersion was filtered, and the surface-treated copper fractions were recovered and heated and dried at 70 DEG C for 1 hour to obtain a surface-treated copper powder.

Table 1 summarizes the treatments carried out on the surface-treated copper foil for each of the examples and comparative examples.

[Evaluation of surface-treated fingers]

The surface-treated copper fractions obtained by the above-described operation were evaluated by the following methods.

[Measuring the size of the dummy]

Measurement of the size of the fingertip was carried out by the following means. The results are summarized in Table 2.

Laser diffraction particle size distribution measurement (Shimadzu SLAD-2100)

[Measurement by TMA]

Samples were prepared from the surface-treated copper powder and the sintering initiation temperature was measured using a TMA (Thermomechanical Analyzer) under the following conditions.

Sample production conditions

Compact size: 7 mmφ × 5 mm Height

Molding pressure: 1 Ton / ㎠ (in 1000 kg / ㎠)

(0.5 wt% zinc stearate was added as a lubricant)

Measuring conditions

Device: Shimadzu TMA-50

Temperature rise: 5 ° C / min

Atmosphere: 2 vol% H ₂ -N ₂ (300 cc / min)

Load: 98.0 mN

As described above, 0.5 wt% of zinc stearate was added to the test sample and mixed. The mixture was charged into a cylinder having a diameter of 7 mm, and the punch was pushed in from the top to maintain the pressure at 1 Ton / And molded into a cylindrical shape having a height of about 5 mm. The molded article was loaded in a heating furnace under the condition that the shaft was in the vertical direction and a load of 98.0 mN was applied in the axial direction and the temperature was raised at a rate of 5 ° C / minute in a 2 vol% H ₂ -N ₂ (300 cc / , The temperature was continuously raised in a measurement range of 50 to 1000 占 폚, and the height change (change in expansion and contraction) of the molded article was automatically recorded. The temperature at the time when the height change (shrinkage) of the molded article started and the shrinkage rate reached 1% was defined as " sintering start temperature ". The measurement results of the sintering initiation temperature in the surface-treated copper fractions for each of the examples and the comparative examples are summarized in Table 3.

For each of the sintered bodies formed by the temperature elevation by TMA, the cross section thereof was observed by TEM to count the number of SiO ₂ having a maximum diameter of 0.5 탆 or more. The obtained results are summarized in Table 3.

Device: STEM

Cross-sectional TEM image magnification: 200,000 times (200,000 times)

[analysis]

Si, N and C adhering to the surface of the surface treated copper powder were analyzed under the following conditions. The results are summarized in Table 3.

Adhesion amount Si The surface-treated copper component was dissolved in an acid and quantified by ICP (inductively coupled plasma atomic emission spectrometry) to determine the mass (g) of Si adhering to the unit mass (g) of the surface treated copper component .

N, C... The amounts of N and C adhered to the entire surface of the copper powder were measured by calculating the amounts of adhered N and C from NO ₂ and CO ₂ generated by melting the copper powder at a high temperature, The mass% (% by weight) of the mass of N and C adhered to the mass was determined.

[Anticorrosion treatment for surface treated copper powder]

The following experiment was carried out (Example 9) to confirm that the surface-treated copper fractions obtained in Example 4 were retained in the sintering retardancy of the present invention even after further rust-proofing treatment.

[Method of rust-inhibiting treatment]

After the copper fractions of Example 4 were obtained, they were dispersed in 100 ml of an aqueous solution of benzotriazole (0.1 g / L), subjected to a rust-preventive treatment, stirred with a rotating blade at 500 rpm for 10 minutes, filtered and dried 70 DEG C x 1 h) to obtain a rust-inhibited copper alloy powder (Example 9).

[Evaluation of rust-inhibited treated fractions]

The rust-inhibited fractions were subjected to evaluation in the same manner as in Example 4 described above, and the results are summarized in Tables 1 to 3. The sizes of the copper fractions after the treatment in Table 2 are the sizes of the copper fractions after the rust-preventive treatment in Example 9, and the evaluations in Table 3 are also the results of the rust-inhibited copper fractions.

In Comparative Examples 1 to 5, tetraethoxysilane (TEOS) was used as a silane coupling agent, and ammonia was used as a catalyst to perform surface treatment on the copper powder. In the case of using tetraethoxysilane The resultant surface-treated copper aggregated, and it was considered that uniform surface treatment and particle size could not be obtained by visual observation. In this case, D50 = 0.13 占 퐉 and Dmax = 0.44 占 퐉 before the surface treatment, but D50 = 0.87 占 퐉 and Dmax = 3.1 占 퐉 after the surface treatment. In addition, the particle size distribution was made up of two acids before the surface treatment.

As a representative example, a TEM image (40,000 times) of a cross-section of the sintered body obtained from the surface-treated copper powder of Example 5 is shown in Fig. The white part is sintered copper and the black part is SiO ₂ particle. SiO ₂ particles were confirmed by performing EDS analysis separately. Further, in order to finish the cross section, the surface was subjected to precision focused ion beam (FIB) processing to obtain a scanning electron microscope (SIM) photograph, thereby counting the number of SiO ₂ particles.

As a result, although the surface-treated copper powder produced by mixing the aqueous aminosilane solution according to the present invention has a very simple manufacturing method, the copper powder is not more than And that it has a high sintering initiation temperature. The sintered body produced by the same sintering as in the production process of the electrodes of the chip laminated ceramic capacitor can be used for the surface-treated copper powder. The sintered body thus produced (formed) , It was found that the number of SiO ₂ grains (number / 탆 ² ) of the large diameter (the diameter of the minimum circumscribed circle of the particles) was small in the section of the sintered body.

From the above results, it was found that it is necessary that the silane coupling agent be an amino silane having an amino group in order to realize sufficient sintering retardancy. It was also found that aminosilane having an amino group at the terminal is preferable as the aminosilane. In Comparative Example 4, although a sufficient amount of Si appeared to adhere to the copper powder, sufficient sintering retardancy was not realized. The reason for this is unclear, but the inventors of the present invention have found that the aminosilane does not have an amino group at the terminal and the benzene ring is present at the end of the amino group in Comparative Example 4, It is presumed that the aminosilane or Si adhered to the copper foil is desorbed from the copper foil at an early stage during the temperature increase for the copper foil.

From the results of Example 9, it can be seen that the surface-treated copper powder according to the present invention retains excellent properties even after the surface treatment with aminosilane, there was. That is, the copper obtained by subjecting the surface treated copper powder according to the present invention to further surface treatment with an organic substance or the like within the range that the surface treatment with aminosilane is not removed or not is also within the scope of the present invention.

[Manufacturing Example]

The fine copper powder was prepared as described below, and the resulting copper powder was surface-treated with aminosilane, and the surface-treated copper powder according to the present invention was uniformly produced by a wet process.

(1) To 0.2 g of gum arabic and 350 ml of pure water, 50 g of copper oxide was added.

(2) Next, 50 ml of diluted sulfuric acid (25 wt%) was added all at once.

(3) This was left to stand for 60 minutes after stirring with a rotating blade (300 rpm x 10 minutes).

(4) Next, cleaning was carried out for the precipitation.

The supernatant was removed, 350 ml of pure water was added, and the mixture was left to stand for 60 minutes after stirring (300 rpm x 10 minutes). The supernatant was removed, 350 ml of pure water was added, ) For 60 minutes, and removing the supernatant.

(5) Next, aminosilane treatment was carried out.

The aminosilane treatment was carried out by adding an aqueous aminosilane solution (50 ml) and stirring for 60 minutes. At that time, a rotating blade (300 rpm) + an ultrasonic wave (manufactured by Techam Co., Ltd., ultrasonic wave cleaner 3 wave type / W- Frequency: 100 kHz). Apart from this, the processing of only the rotating blades (300 rpm) and the processing of only ultrasonic waves were carried out separately. Diaminosilane A-1120 (manufactured by MOMENTIVE) and aminosilane A-1110 (manufactured by MOMENTIVE) were used as the aminosilane, respectively.

(6) Next, filtration was performed to separate the precipitate.

(7) Next, the separated precipitate was dried. Drying (70 ° C × 2 h) was carried out by drying in an air atmosphere and drying in nitrogen, respectively.

The surface-treated fine copper powder was thus obtained by coherent manufacturing. The surface-treated copper fractions obtained in this way had an excellent sintering retardancy as in the case of the surface-treated copper particles of Examples 1 to 9, and the number of large particles of SiO ₂ existing in the cross section of the sintered body was small. In addition, this consistent manufacturing can be carried out without drying until the final product is obtained, which is convenient and excellent in workability.

[Example]

The present invention will be described in further detail with reference to the following examples in addition to the above-described embodiments. The present invention is not limited to the following examples.

[Metal powder]

Copper fine powder, nickel powder and silver powder were prepared as metal powders in the following order.

(Copper fine powder)

Examples 15 to 17 and Comparative Example 9

20 g of the copper component to be subjected to the surface treatment was produced by the above-described wet method. In other words,

(1) 50 g of copper oxide was added to 0.4 g of gum arabic and 350 ml of pure water.

(2) Next, 50 ml of diluted sulfuric acid (25 wt%) was added all at once.

(3) This was left to stand for 60 minutes after stirring with a rotating blade (300 rpm x 10 minutes).

(4) Next, the precipitate was washed.

The supernatant was removed, 350 ml of pure water was added, and the mixture was left to stand for 60 minutes after stirring (300 rpm x 10 minutes). The supernatant was removed, 350 ml of pure water was added, ) And left for 60 minutes to precipitate the copper fine powder. In this state, particle size measurement was carried out by laser diffraction particle size distribution measurement (Shimadzu SLAD-2100), and the particle size before surface treatment was measured.

Table 3 shows the obtained particle size (D50, Dmax). The measurement was performed using a laser diffraction particle size distribution measuring apparatus (SALD-2100 manufactured by Shimadzu Corporation).

Example 10

According to Japanese Patent No. 4164009, a copper powder was obtained by a chemical reduction method. Namely, 2 g of gum arabic was added to 2900 ml of pure water, and then 125 g of copper sulfate was added thereto. While stirring, 360 ml of 80% hydrazine monohydrate was added. After the addition of hydrazine monohydrate, the temperature was raised from room temperature to 60 占 폚 over a period of 3 hours, and the copper oxide was further reacted for 3 hours. After the completion of the reaction, the resulting slurry was filtered with a sieve, then washed with pure water and methanol, and further dried to obtain a coarse powder. This mixture was mixed with an aqueous solution of diaminosilane coupling agent in the order of Example 1 to obtain a surface-treated silver powder. This property was evaluated in the order of Example 1.

(Nickel)

The nickel powder was NF32 (D50 0.3 mu m) manufactured by Tohto Titanium.

(Silver)

It was milled according to Japanese Patent Laid-Open No. 2007-291513. Namely, 12.6 g of silver nitrate was dissolved in 0.8 L of pure water, 24 mL of 25% ammonia water was added, and further 40 g of ammonium nitrate was added to adjust the silver ammine complex salt aqueous solution. Gelatin was added thereto at a ratio of 1 g / l, and this was used as an electrolytic solution. Both the positive electrode and the negative electrode were electrolyzed using a DSE electrode plate at a current density of 200 A / m ² and a solution temperature of 20 캜, It was electrolyzed for 1 hour while being scraped off. The silver powder thus obtained was filtered with a sieve, washed with pure water and alcohol in this order, and dried in air at 70 캜 for 12 hours. This silver powder was dry-classified and finally silver powder having a D50 of 0.1 mu m and a Dmax of 0.5 mu m was obtained.

 (Preparation of coupling agent aqueous solution)

50 ml of each of the following silane aqueous solutions was prepared.

Silane: Diaminosilane A-1120 (manufactured by MOMENTIVE)

Methyltrimethoxysilane KBM-13 (manufactured by Shin-Etsu Silicone Co., Ltd.)

Titanate: Amino group-containing Plain Act KR44 (manufactured by Ajinomoto Fine Techno Co., Ltd.)

Free ACTIVE KR TTS (manufactured by Ajinomoto Fine Techno Co., Ltd.)

The concentration was in the range of 1 to 10 vol%. Further, the pH was adjusted to 4 with dilute sulfuric acid other than the amino-based coupling agent.

The structural formulas of various silanes are as follows.

Diamino silane A-1120:

H ₂ N-C ₂ H ₄ -NH-C ₃ H ₆ -Si (OCH ₃ ) ₃

Methyltrimethoxysilane KBM-13:

H ₃ C-Si (OCH ₃ ) ₃

Amino group-containing plain act KR44

Side chain organic functionalities of the hydrophobic group

(CH _{3) 2} CH-O-

Side chain organic functional group of hydrophilic group

-O- (C ₂ H ₄ ) -NH- (C ₂ H ₄ ) -NH ₂

Non-amino group free act KR TTS

Side chain organic functionalities of the hydrophobic group

(CH _{3) 2} CH-O-

Side chain organic functional group of hydrophilic group

_{-O-CO- (C 17 H 35} )

(Surface treatment)

The supernatant was removed from the copper fine powder slurry obtained in the order of the above (copper fine powder), and the copper fine powder was mixed with the coupling agent prepared in the above (preparation of the coupling agent aqueous solution) for 60 minutes in any of the following methods Examples 15 to 17 and Comparative Example 9).

(1) Rotating blade (300 rpm) + Ultrasonic wave (3-frequency type ultrasonic cleaner / W-113) (output 100 W, frequency 100 kHz)

(2) Rotary blades (300 rpm) only

(3) Ultrasonic only

Next, the coupling agent aqueous solution was suction filtered through an aspirator, and then 350 ml of pure water was added to the copper fine powder, followed by further filtration. This was dried at 70 DEG C for 1 hour under a nitrogen atmosphere and pulverized with induction. In this state, particle size measurement was carried out again.

For Example 10, surface treatment was carried out in the order of (1) described above as described in (copper fine powder).

The nickel powder obtained in the above (nickel powder) and the silver powder obtained in the above (silver powder) were mixed with the coupling agent prepared in the above (preparation of the coupling agent aqueous solution) in the order of (1) described above for 60 minutes, (Examples 11 to 14 and 18 to 23, Comparative Examples 6, 8, 10 and 11).

The obtained results are shown in Tables 4 to 6 below.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, it has been found that even when a metal powder other than the copper powder is used or a coupling agent other than the silane coupling agent is used, a surface treated metal powder having excellent properties can be obtained.

Industrial availability

The present invention provides a surface-treated copper alloy which does not agglomerate even after surface treatment, has excellent sintering retardancy, and exhibits a high sintering initiation temperature even if the particles are small in number. The surface-treated copper powder according to the present invention can be produced by subjecting the copper powder to a very simple treatment, and this production method does not require a high-level function and is excellent in workability and productivity. The present invention is an industrially useful invention.

Claims (54)

Wherein the amount of adhesion of at least one of Si, Ti, Al, Zr, Ce and Sn is 200 to 16000 占 퐂 per 1 g of the copper content and the weight percentage of N relative to the copper content is 0.02 to 0.5%
The surface-treated copper is a copper-treated surface treated with a coupling agent,
Coupling Agent A surface-treated co-agent which is a coupling agent whose terminal is an amino group. delete delete delete The method according to claim 1,
And the adhesion amount of at least one of Si, Ti, Al, Zr, Ce and Sn is 300 to 16000 ㎍ for 1 g of the copper content. The method according to claim 1,
And the adhesion amount of any one or more of Si, Ti, Al, Zr, Ce, and Sn is 500 to 16000 ㎍ for 1 g of copper. The method according to claim 1,
Wherein the adhesion amount of any one or more of Si, Ti, Al, Zr, Ce, and Sn is not less than 200 袖 g and not more than 3000 쨉 g per 1 g of the copper content. The method according to claim 1,
Wherein the adhesion amount of any one or more of Si, Ti, Al, Zr, Ce and Sn is not less than 200 쨉 g and not more than 1,500 쨉 g per 1 g of the copper content. The method according to claim 1,
A coarse fraction in which the weight percentage of N relative to the copper content is not less than 0.05% and not more than 0.5%. The method according to claim 1,
Wherein at least one of Si, Ti, Al, Zr, Ce and Sn is at least one of Ti, Al, Zr, Ce and Sn. The method according to claim 1,
And at least one of Si, Ti, Al, Zr, Ce, and Sn is Si. The method according to claim 1,
The adhesion amount of Si is 500 to 16000 에 for 1 g of the copper content, and the weight percentage of N relative to the copper content is 0.05% to 0.5%. The method according to claim 1,
The adhesion amount of Si is 500 to 3000 占 퐂 per 1 g of the copper content, and the weight percentage of N relative to the copper content is not less than 0.05% and not more than 0.5%. delete The method according to claim 1,
Wherein at least one of Si, Ti, Al, Zr, Ce and Sn is adsorbed by a coupling agent treatment. The method according to claim 1,
The coupling agent is one of silane, titanate, and aluminate. delete The method according to claim 1,
The coupling agent is an aminosilane. The method according to claim 1,
Sintering temperature of 400 ° C or higher. 19. The method of claim 18,
Wherein the aminosilane is a monoaminosilane or a diaminosilane. A surface-treated copper powder obtained by surface-treating the copper according to claim 1 with an organic compound. delete A conductive fountain paste using the copper foil according to any one of claims 1, 5 to 13, 15, 16 and 18 to 21. An electrode comprising the conductive copper paste as set forth in claim 23 coated thereon and fired by heating,
Wherein at least one of SiO ₂ , TiO _2, and Al ₂ O ₃ having a maximum diameter of 0.5 탆 or more is present at 0.5 or less / ² 탆 on the electrode surface. A chip-laminated ceramic capacitor produced by using the paste according to claim 23. 26. The method of claim 25,
In which SiO ₂ , TiO _2, or Al ₂ O ₃ having a diameter of 10 nm or more exists in the end face of the internal electrode. 26. The method of claim 25,
Chip, a multilayer ceramic capacitor that is a maximum diameter of 0.5 ㎛ or more SiO _2, TiO ₂ or Al ₂ O ₃ exists in ² or less 0.5 number / ㎛ in the electrode cross-section. A multilayer substrate comprising the chip multilayer ceramic capacitor according to claim 25 mounted on an outermost layer. A multilayer substrate comprising the chip multilayer ceramic capacitor according to claim 25 mounted on an inner layer. 29. An electronic device on which the multi-layer substrate according to claim 28 is mounted. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete 29. An electronic component mounted with the multi-layer substrate according to claim 29.

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