JP6482889B2 - Surface protective agent composition, electric connection structure using the same, and method for producing electric connection structure - Google Patents

Description

  The present invention relates to a surface protective agent composition, an electrical connection structure using the same, and a method for producing the electrical connection structure, and more particularly, a surface protective composition excellent in corrosion inhibition of metal members and an electrical connection using the same. The present invention relates to a structure and a method for manufacturing an electrical connection structure.

In a part where two metal members are electrically connected, such as a terminal and an electric wire, or a fitting part between the terminals, the material that constitutes the terminal and the electric wire, the material that constitutes the terminal and the counterpart terminal, the terminal The material of the metal plate to be formed and the plating layer formed on the surface of the metal plate may be made of different metals.
In this way, when a member made of a dissimilar metal is arranged at a close position, water (particularly, an aqueous solution containing ions such as chloride) adheres between the dissimilar metals and a corrosion current flows. Is concerned. In order to avoid such a problem, grease or the like is applied to a connection portion between terminals (see, for example, Patent Document 1).

  As described in Patent Document 1, when an oil component such as grease is applied, stickiness or dripping occurs, which may impair workability and may contaminate surrounding substrates. For this reason, it is necessary to apply as thinly as possible. However, if it is applied too thinly, it will be difficult to maintain a stable oil film on the metal surface for a long period of time. In particular, under high temperature conditions, it may be accompanied by low molecular weight and volatilization due to oxidation of the oil component, making it more difficult to maintain a stable oil film on the metal surface. This is because the oil component does not chemically bond to the metal surface, and the oil component is in close contact with the metal surface by van der Waals force having a weak suction force.

Japanese Patent Application Laid-Open No. 5-159646

  The present invention has been made in view of the above circumstances, and the problem to be solved by the present invention is to provide a surface protective agent composition that suppresses corrosion of a member due to a corrosion current between metals in adjacent dissimilar metal members. In addition, an object is to provide an electrical connection structure using the same and a method of manufacturing the electrical connection structure.

  As a result of intensive studies in order to solve the above problems, the present inventors have found that a first metal member containing copper or a copper alloy (a tin plating layer may be partially or entirely formed), and the first A surface protective agent composition comprising: a second metal member electrically connected to one metal member; and a surface protective layer formed on a surface of the first metal member, wherein the surface protective layer has a specific structure. It has been found that it is effective to form by coating, and the present invention has been completed.

That is, the present invention is as follows.
[1] (a) To the lubricating base oil,
(B) at least one compound selected from the group consisting of a phosphorus compound represented by the following general formula (1) and a phosphorus compound represented by the general formula (2), in terms of phosphorus element, based on the total amount of the composition As 0.005-2.0 mass%,

(In General Formula (1), X ¹ , X ² and X ³ each independently represent an oxygen atom or a sulfur atom, and at least one of them is an oxygen atom, and R ¹¹ , R ¹² and R 3 ¹³ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms)

(In General Formula (2), X ⁴ , X ⁵ , X ⁶ and X ⁷ each independently represent an oxygen atom or a sulfur atom, and at least three of these are oxygen atoms, R ¹⁴ , R ¹⁵ and R ¹⁶ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms)
(C) 0.1 to 40% by mass of the amide compound based on the total amount of the composition,
(D) Alkali metal or alkaline earth metal salicylate having an alkyl group or alkenyl group having 10 to 40 carbon atoms, and / or a (over) basic salt thereof, based on the total amount of the composition, 0 0.005 to 3.0 mass%,
A surface protective agent composition comprising:

[2] The surface protective agent composition according to [1], wherein the (a) lubricating base oil has a kinematic viscosity at 100 ° C. of ² to 50 mm ² / s.

[3] (b) All of X ⁴ , X ⁵ , X ⁶ and X ^{7 in} the general formula (2) of the phosphorus compound represented by the general formula (2) are oxygen atoms, and R The surface protective agent composition according to the above [1] or [2], wherein at least one of ¹⁴ , R ¹⁵ and R ¹⁶ is a hydrocarbon group having 1 to 30 carbon atoms.
[4] (b) All of X ⁴ , X ⁵ , X ⁶ and X ⁷ in the general formula (2) of at least one of the phosphorus compounds represented by the general formula (2) are oxygen atoms; ^14. The surface protective agent composition according to [1] or [2] above, wherein at least one of R ¹⁵ and R ¹⁶ is a branched hydrocarbon group having 8 to 30 carbon atoms.

[5] (c) The surface protective agent composition according to any one of [1] to [4], wherein the amide compound is at least one kind represented by the following general formulas (3) to (5): .
^{R 21 -CO-NH-R 22} (3)
^{R 23 -CO-NH-Y 31} -NH-CO-R 24 (4)
^{R 25 -NH-CO-Y 32} -CO-NH-R 26 (5)
(In General Formulas (3) to (5), R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms. R ²² may be hydrogen, Y ³¹ and Y ³² are each selected from the group consisting of an alkylene group having 1 to 10 carbon atoms, a phenylene group, or an alkylphenylene group having 7 to 10 carbon atoms. 1 to 10 divalent hydrocarbon groups)
[6] (c) The amide compound is at least one amide compound represented by the general formulas (3) to (5), and R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ are Each independently a saturated chain hydrocarbon group having 12 to 20 carbon atoms, or an amide compound in which R ²² is hydrogen and / or R ²¹ and R ²² , R ²³ and R ²⁴ , and at least one of R ²⁵ and R ²⁶ The surface protective agent composition according to [5] above, wherein one of the amide compounds is an unsaturated chain hydrocarbon group having 12 to 20 carbon atoms.
[7] The surface protective agent composition according to any one of [1] to [6], wherein (c) the amide compound is a fatty acid amide having a melting point of 20 ° C to 200 ° C.

[8] (d) an alkali metal or alkaline earth metal salicylate having an alkyl group or an alkenyl group having 10 to 40 carbon atoms and / or a (over) basic salt thereof is an alkyl group or alkenyl having 10 to 40 carbon atoms The surface protective agent composition according to any one of the above [1] to [7], which is a calcium salicylate having a group and / or a (over) basic salt thereof.
[9] (d) an alkali metal or alkaline earth metal salicylate having an alkyl group or an alkenyl group having 10 to 40 carbon atoms and / or a (over) basic salt thereof is an alkyl group or alkenyl having 10 to 40 carbon atoms Any one of the above [1] to [8], which is an alkali metal or alkaline earth metal salicylate having a group and / or a (over) basic salt thereof, wherein the metal ratio is 1 to 7.5 The surface protection agent composition as described.

[10] The surface protective agent composition according to any one of [1] to [9], further comprising (e) 0.01 to 5% by mass of an antioxidant based on the total amount of the composition. object.
[11] The surface protective composition according to [10] above, wherein (e) the antioxidant is at least one selected from the group consisting of phenolic antioxidants and amine antioxidants.
[12] The surface protective composition according to [10], wherein (e) the antioxidant is at least one selected from the group consisting of alkylphenols and bisphenols.

[13] The surface protective agent composition according to any one of the above [1] to [12], further comprising (f) 0.1 to 20% by mass of a thickener based on the total amount of the composition. object.
[14] In the above [13], (f) the thickener is at least one selected from the group consisting of polyalkyl methacrylate, ethylene-α-olefin copolymer or a hydride thereof, polyisobutylene and a hydride thereof. The surface protection agent composition as described.

[15] The surface protective agent composition according to any one of [1] to [14], further comprising (g) 0.1 to 10% of grease based on the total amount of the composition.
[16] The surface protective composition according to [15], wherein the grease (g) is a lithium-based grease.
[17] The surface protective agent composition according to any one of [1] to [16], further comprising (h) a dye.
[18] The surface protective agent composition according to any one of [1] to [17], which has a melting point of 120 ° C to 150 ° C.

[19] In an electrical connection structure including a first metal member containing copper or a copper alloy and a second metal member electrically connected to the first metal member, at least the surface of the first metal member is The electrical connection structure in which the surface protective layer which consists of a surface protective agent composition as described in any one of [1]-[18] was formed.
[20] The electrical connection structure according to the above [19], wherein the first metal member containing copper or a copper alloy has a tin plating layer formed at least in part.
[21] The electrical connection structure according to [19] or [20], wherein the second metal member is aluminum or an aluminum alloy.
[22] The electrical connection structure according to [19] or [20], wherein the second metal member is an aluminum electric wire or an aluminum alloy electric wire.
[23] The electrical connection structure according to [19] or [20], wherein the second metal member is copper or a copper alloy.
[24] The electrical connection structure according to [19] or [20], wherein the second metal member is a copper wire or a copper alloy wire.

[25] In an electrical connection structure comprising a first metal member containing copper or a copper alloy and a second metal member electrically connected to the first metal member, at least the surface of the first metal member is A method for inhibiting corrosion of an electrical connection structure, wherein a surface protective layer comprising the surface protective agent composition according to any one of [1] to [18] is formed.
[26] The above [1] to [18], wherein the surface protective layer of the electrical connection structure according to any one of [19] to [24] is heated to a melting point or higher. Electrical connection structure obtained by dip-coating on the surface protective agent composition.
[27] A wire harness for an automobile using the electrical connection structure according to any one of [19] to [24] and [26].
[28] A method for reducing the weight of an automobile using the automobile wire harness described in [27].

With the surface protective agent composition of the present invention, corrosion of the metal member can be suppressed in the electrical connection structure of the metal member.
Moreover, since the surface protective agent composition of the present invention can improve the corrosion durability of metal members even under severe corrosive environments, it improves the durability of wiring of transportation equipment such as automobile wire harnesses. be able to.
Furthermore, the electrical connection structure to which the surface protective agent composition of the present invention is applied can suppress the corrosion resistance of aluminum (alloy), which has been difficult to suppress corrosion in a corrosive environment.
Furthermore, the electrical connection structure to which the surface protective agent composition of the present invention is applied enables aluminum (alloy), which is effective for reducing the weight of the vehicle, to be used as the material for the core wire of the wire harness. It contributes to weight reduction, and can contribute to fuel saving and reduction of carbon dioxide emissions.

FIG. 1 is a schematic diagram for explaining an electrical connection structure according to Embodiment 1 of the present invention. FIG. 2 is a schematic diagram for explaining the electrical connection structure according to the first embodiment of the present invention. FIG. 3 is a schematic diagram for explaining the electrical connection structure according to the first embodiment of the present invention. FIG. 4 is a schematic diagram for explaining an electrical connection structure according to the second embodiment of the present invention.

Hereinafter, the contents of the present invention will be described in more detail.
The surface protective agent composition of the present invention is blended with (a) a lubricant base oil (hereinafter also referred to as “component (a)”).
As said (a) component, the arbitrary mineral oil used as a base oil of a normal lubricating oil, wax isomerized oil, the 1 type, or 2 or more types of mixture of synthetic oil can be used.
Specifically, as mineral oil, for example, a lubricating oil fraction obtained by subjecting crude oil to atmospheric distillation and reduced pressure distillation is subjected to solvent removal, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrogenation. Paraffinic and naphthenic oils, normal paraffins, and the like purified by appropriately combining purification, sulfuric acid washing, purification treatment such as clay treatment, and the like can be used.

  Wax isomerized oil includes natural wax such as petroleum slack wax obtained by dewaxing hydrocarbon oil, or so-called Fischer Tropsch synthesis in which a mixture of carbon monoxide and hydrogen is brought into contact with a suitable synthesis catalyst at high temperature and high pressure. Those prepared by hydroisomerizing a wax raw material such as synthetic wax produced by the method can be used. When slack wax is used as a wax raw material, slack wax contains a large amount of sulfur and nitrogen, and these are not necessary for lubricating base oils. It is desirable to use a wax having a reduced content as a raw material.

  The synthetic oil is not particularly limited, but poly-α-olefin (1-octene oligomer, 1-decene oligomer, ethylene-propylene oligomer, etc.) and hydrides thereof, isobutene oligomer and hydrides thereof, isoparaffin, alkylbenzene, Alkyl naphthalene, diester (ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditridecyl adipate, di-2-ethylhexyl sebacate, etc.), polyol ester (trimethylolpropane caprylate, trimethylolpropane pelargonate, penta Erythritol 2-ethylhexanoate, pentaerythritol pelargonate, etc.), polyoxyalkylene glycol, dialkyldiphenyl ether, and polypheny Ether and the like can be used.

The kinematic viscosity of these lubricating base oils is not particularly limited and is arbitrary, but usually the kinematic viscosity at 100 ° C. is preferably 1 to 70 mm ² / s. It is more preferable that the kinematic viscosity at 100 ° C. is ² to 50 mm ² / s because of excellent volatility and ease of handling during production.

  The surface protective agent composition of the present invention includes (b) at least one compound selected from the group consisting of a phosphorus compound represented by the following general formula (1) and a phosphorus compound represented by the general formula (2) ( Hereinafter, “(b) component”) is blended.

In the general formula (1), X ¹ , X ² and X ³ each independently represent an oxygen atom or a sulfur atom, and at least one of them is an oxygen atom, and R ¹¹ , R ¹² and R ¹³ Each independently represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.

In the general formula (2), X ⁴ , X ⁵ , X ⁶ and X ⁷ each independently represent an oxygen atom or a sulfur atom, and at least three of these are oxygen atoms, and R ¹⁴ , R ¹⁵ And R ¹⁶ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.
Specific examples of the hydrocarbon group having 1 to 30 carbon atoms represented by R ^{11 to} R ¹⁶ include an alkyl group, a cycloalkyl group, an alkenyl group, an alkyl-substituted cycloalkyl group, an aryl group, and an alkyl-substituted aryl group. And arylalkyl groups.

  Examples of the alkyl group include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, and the like. Group, hexadecyl group, heptadecyl group, octadecyl group and other alkyl groups (these alkyl groups may be linear or branched).

  As said cycloalkyl group, C5-C7 cycloalkyl groups, such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, can be mentioned, for example. Examples of the alkylcycloalkyl group include a methylcyclopentyl group, a dimethylcyclopentyl group, a methylethylcyclopentyl group, a diethylcyclopentyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a methylethylcyclohexyl group, a diethylcyclohexyl group, a methylcycloheptyl group, Examples thereof include an alkylcycloalkyl group having 6 to 11 carbon atoms such as a dimethylcycloheptyl group, a methylethylcycloheptyl group, and a diethylcycloheptyl group (the substitution position of the alkyl group with the cycloalkyl group is also arbitrary).

  Examples of the alkenyl group include butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, An alkenyl group such as an octadecenyl group (these alkenyl groups may be linear or branched, and the position of the double bond is also optional).

As said aryl group, aryl groups, such as a phenyl group and a naphthyl group, can be mentioned, for example. Examples of the alkylaryl group include tolyl group, xylyl group, ethylphenyl group, propylphenyl group, butylphenyl group, pentylphenyl group, hexylphenyl group, heptylphenyl group, octylphenyl group, nonylphenyl group, and decylphenyl. A C7-C18 alkylaryl group such as a group, undecylphenyl group, dodecylphenyl group, etc. (the alkyl group may be linear or branched, and the substitution position on the aryl group is arbitrary) Can do.
Examples of the arylalkyl group include arylalkyl groups having 7 to 12 carbon atoms such as benzyl group, phenylethyl group, phenylpropyl group, phenylbutyl group, phenylpentyl group, and phenylhexyl group. It may be branched).

The hydrocarbon group having 1 to 30 carbon atoms represented by R ^{11 to} R ¹⁶ is preferably an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 24 carbon atoms, and has 3 to 18 carbon atoms. An alkyl group or an aryl group having 3 to 18 carbon atoms is more preferable.

Of X ^{1 to} X ^{3 in} the general formula (1), two or more of them are preferably oxygen atoms, and more preferably all three are oxygen atoms.
Of X ^{4 to} X ^{7 in} the general formula (2), two or more of them are preferably oxygen atoms, more preferably three or more are oxygen atoms, and particularly preferably all are oxygen atoms. .

X ⁴ , X ⁵ , X ⁶ and X ^{7 in} the general formula (2) are all oxygen atoms, and at least one of R ¹⁴ , R ¹⁵ and R ¹⁶ is a hydrocarbon group having 1 to 30 carbon atoms. Preferably, all of X ⁴ , X ⁵ , X ⁶ and X ^{7 in} the general formula (2) are oxygen atoms, and at least one of R ¹⁴ , R ¹⁵ and R ¹⁶ is a branched hydrocarbon having 8 to 30 carbon atoms. More preferably, it is a group.

As a phosphorus compound represented by General formula (1), the following phosphorus compounds can be mentioned, for example.
Phosphorous acid, monothiophosphorous acid, dithiophosphorous acid; phosphorous acid monoester, monothiophosphorous acid monoester, dithiophosphorous acid monoester having one hydrocarbon group having 1 to 30 carbon atoms; Phosphorous acid diester having two hydrocarbon groups having 1 to 30 carbon atoms, monothiophosphorous acid diester, dithiophosphorous acid diester; Phosphorous acid triester having three hydrocarbon groups having 1 to 30 carbon atoms, monothio Phosphite triesters, dithiophosphite triesters; and mixtures thereof.

As a phosphorus compound represented by General formula (2), the following phosphorus compounds can be mentioned, for example.
Phosphoric acid, monothiophosphoric acid, dithiophosphoric acid, trithiophosphoric acid; phosphoric acid monoester, monothiophosphoric acid monoester, dithiophosphoric acid monoester, trithiophosphoric acid monoester having one hydrocarbon group having 1 to 30 carbon atoms; Phosphoric acid diester having 2 hydrocarbon groups of ˜30, monothiophosphoric acid diester, dithiophosphoric acid diester, trithiophosphoric acid diester; phosphoric acid triester having 3 hydrocarbon groups having 1 to 30 carbon atoms, monothiophosphoric acid triester, Dithiophosphoric acid triesters, trithiophosphoric acid triesters; and mixtures thereof.

One type or two or more types of these (b) components can be arbitrarily blended.
In the surface protective agent composition of the present invention, the amount of component (b) is 0.005% by mass or more in terms of phosphorus element based on the total amount of the composition, while the content is 2.0% by mass. It is as follows. When the content of the component (b) is less than 0.005% by mass in terms of phosphorus element, the effect on the protection of the metal surface is poor, and when it exceeds 2.0% by mass, it is only commensurate with the blending amount. Since the protective effect on the metal surface is not obtained, it is not preferable.

In the surface protective agent composition of the present invention, (c) an amide compound (hereinafter also referred to as “component (c)”) is blended.
The component (c) is an amide compound having one or more amide groups (—NH—CO—), wherein the amide group represented by the following formula (3) has one monoamide compound, the formula (4) And the bisamide compound represented by Formula (5) can be used preferably.

^{R 21 -CO-NH-R 22} (3)
^{R 23 -CO-NH-Y 31} -NH-CO-R 24 (4)
^{R 25 -NH-CO-Y 32} -CO-NH-R 26 (5)

In the general formulas (3) to (5), R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms. R ²² may be hydrogen, Y ³¹ and Y ³² may be selected from the group consisting of an alkylene group having 1 to 10 carbon atoms, a phenylene group, or an alkylphenylene group having 7 to 10 carbon atoms. 10 to 10 divalent hydrocarbon groups.

The monoamide compound is represented by the above formula (3), but part of the hydrogen of the hydrocarbon group constituting R ²¹ and R ²² may be substituted with a hydroxyl group (—OH). Specific examples of such monoamide compounds include saturated fatty acid amides such as lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide, and unsaturated fatty acids such as oleic acid amide and erucic acid amide. Examples thereof include amides, and substituted amides of saturated or unsaturated long-chain fatty acids and long-chain amines such as stearyl stearamide, oleyl oleate, oleyl stearate, stearyl oleamide, and the like.
Among these amide compounds, R ²¹ and R ²² in formula (3) are each independently a saturated chain hydrocarbon group having 12 to 20 carbon atoms, or R ²² is hydrogen and / or R ^21. , R ²² is preferably an amide compound in which an unsaturated chain hydrocarbon group having 12 to 20 carbon atoms is used. Specifically, stearyl stearamide is preferable.

The bisamide compound is a compound represented by the above formulas (4) and (5) in the form of a diamine acid amide or a diacid acid amide. In the hydrocarbon groups represented by R ²³ , R ²⁴ , R ²⁵ and R ²⁶ , and Y ³¹ and Y ³² in the formulas (4) and (5), some hydrogen atoms are hydroxyl groups (—OH). May be substituted.

Specific examples of the bisamide compound represented by the formula (4) include ethylene bisstearic acid amide, ethylene bisisostearic acid amide, ethylene bisoleic acid amide, methylene bislauric acid amide, hexamethylene bisoleic acid amide, and hexamethylene. Examples thereof include bishydroxystearic acid amide and m-xylylene bisstearic acid amide. Specific examples of the amide compound represented by the formula (5) include N, N′-distearyl sebacic acid amide.
Among these bisamide compounds, as in the case of the monoamide compound, R ²³ and R ^{24 in} formula (4) and R ²⁵ and R ^{26 in} formula (5) are each independently a saturated chain carbonization having 12 to 20 carbon atoms. Preferably, the amide compound of a hydrogen group and / or at least one of R ²³ and R ²⁴ and R ²⁵ and R ²⁶ is an amide compound of an unsaturated chain hydrocarbon group having 12 to 20 carbon atoms. And ethylene bis-stearic acid amide.

One type or two or more types of these (c) components can be arbitrarily blended.
When the amide compound is uniformly mixed with a liquid lubricating base oil, a gel-like composition is formed at room temperature. That is, the amide compound functions as a semi-solid compound that makes a liquid lubricating base oil semi-solid (gelled) at room temperature. The surface of the present invention is considered to be semi-solid at room temperature, which functions as a metal surface protective agent, and to be used in a liquid state at high temperature in order to form a uniform surface protective film on the metal surface. The melting point of the amide compound to be blended in the protective agent composition is preferably 20 to 200 ° C, more preferably 80 to 180 ° C, and particularly preferably 120 to 150 ° C. Moreover, 100-1000 are preferable and, as for the molecular weight of an amide compound, it is more preferable that it is 150-800.

  In the surface protective agent composition of the present invention, the amount of component (c) is 0.1% by mass or more, preferably 1% by mass or more, more preferably 5% by mass or more based on the total amount of the composition. On the other hand, the compounding quantity is 40 mass% or less, Preferably it is 30 mass% or less. When the amount of component (c) is less than 0.1% by mass, a gel-like composition cannot be formed at room temperature, and when it exceeds 40% by mass, the surface protective agent composition has handleability. Since they become scarce, they are not preferable.

The surface protective agent composition of the present invention includes (d) an alkali metal or alkaline earth metal salicylate having an alkyl group or an alkenyl group having 10 to 40 carbon atoms, and / or a (over) basic salt thereof (hereinafter, “ (D) also referred to as “component”).
Examples of the alkali metal or alkaline earth metal of component (d) include sodium, potassium, magnesium, barium, calcium and the like, and calcium is particularly preferably used.

  Examples of the alkyl group having 10 to 40 carbon atoms include a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, and the like. It may be branched).

  Examples of the alkenyl group having 10 to 40 carbon atoms include a decenyl group, an undecenyl group, a dodecenyl group, a tridecenyl group, a tetradecenyl group, a pentadecenyl group, a hexadecenyl group, a heptadecenyl group, an octadecenyl group, etc. It may be branched, and the position of the double bond is arbitrary.

  There is no restriction | limiting in particular as a manufacturing method of (d) component, The manufacturing method etc. of a well-known monoalkyl salicylate can be used, For example, using phenol as a starting material and an equivalent C10-40 olefin. Monoalkyl salicylic acid obtained by alkylation and then carboxylation with carbon dioxide gas or the like, or monoalkyl salicylic acid obtained by alkylation using salicylic acid as the starting material and equivalent amount of the above olefin, etc. It can be obtained by reacting with a metal base such as an oxide or hydroxide of an earth metal, or by once replacing an alkali metal salt such as a sodium salt or potassium salt with an alkaline earth metal salt.

  The component (d) of the present invention comprises an alkali metal or alkaline earth metal salicylate (neutral salt) obtained as described above, an excess of an alkali metal or alkaline earth metal salt, an alkali metal or an alkaline earth. In the presence of a basic salt obtained by heating a metal base (a hydroxide or oxide of an alkali metal or alkaline earth metal) in the presence of water, carbon dioxide, boric acid or borate. An overbased salt obtained by reacting a basic salt with a base such as an alkali metal or alkaline earth metal hydroxide is also included.

  The component (d) of the present invention preferably uses a (over) basic salt, and the metal ratio of the inorganic compound such as calcium carbonate constituting the component (d) to the organic compound is 1 to 7.5. More preferably, it is 1-5, More preferably, it is 1-3.5. The metal ratio here is represented by the valence of the metal element of the (over) basic salt × metal element content (mol%) / soap group content (mol%), and the metal element is calcium, magnesium, etc. The soap group means a salicylic acid group or the like.

One type or two or more types of these components (d) can be arbitrarily blended.
In the surface protective agent composition of the present invention, the blending amount of the component (d) is 0.005% by mass or more in terms of metal element based on the total amount of the composition, while the content is 3.0% by mass. It is as follows. When the content of the component (d) is less than 0.005% by mass in terms of metal element, the effect on the protection of the metal surface is poor, and when it exceeds 3.0% by mass, it is only commensurate with the blending amount. Since the protective effect on the metal surface is not obtained, it is not preferable.

In order to improve the thermal / oxidative stability of the composition, it is preferable to add an antioxidant (hereinafter also referred to as “component (e)”) to the surface protective agent composition of the present invention.
As said (e) component, what is generally used for lubricating oils, such as a phenol type compound and an amine type compound, can be used. Of these, alkylphenols such as hindered phenols and bisphenols are more preferable.
Specifically, alkylphenols such as 2,6-di-tert-butyl-4-methylphenol and bisphenols such as methylene-4,4-bisphenol (2,6-di-tert-butyl-4-methylphenol) , Naphthylamines such as phenyl-α-naphthylamine, dialkyldiphenylamines, zinc dialkyldithiophosphates such as zinc di-2-ethylhexyldithiophosphate, (3,5-di-tert-butyl-4-hydroxyphenyl) fatty acid ( Propionic acid and the like) and mono- or polyhydric alcohols such as methanol, octadecanol, 1,6-hexadiol, neopentyl glycol, thiodiethylene glycol, triethylene glycol, pentaerythritol and the like.
One or two or more kinds of antioxidants arbitrarily selected from these can be blended in any amount, but the content is usually 0.01-5. It is preferably 0% by mass.

In order to improve the surface protection property of the composition, it is preferable to add a thickener (hereinafter also referred to as “component (f)”) to the surface protective agent composition of the present invention.
Specifically, the component (f) is a so-called non-dispersed viscosity index such as a copolymer of one or two or more monomers selected from various methacrylic esters such as polyalkyl methacrylate or a hydrogenated product thereof. Examples thereof include a so-called dispersion type viscosity index improver obtained by copolymerizing an improver or various methacrylates further containing a nitrogen compound. Specific examples of other viscosity index improvers include non-dispersed or dispersed ethylene-α-olefin copolymers (the α-olefin can be exemplified by propylene, 1-butene, 1-pentene, etc.) and hydrides thereof. , Polyisobutylene and hydrogenated products thereof, styrene-diene hydrogenated copolymer, styrene-maleic anhydride ester copolymer, and polyalkylstyrene.
One or two or more kinds of thickeners arbitrarily selected from these can be mixed in any amount, but the content is usually 0.1 to 20 mass based on the total amount of the composition. % Is preferred.

In order to improve the surface protection property of the composition, it is preferable to further add a grease (hereinafter also referred to as “(g) component”) to the surface protective agent composition of the present invention.
As the component (g), specifically, a mineral oil and / or a chemical synthetic oil such as poly-α-olefin and a fatty acid ester is used as a base oil, and a metal soap and / or a urea compound is used as a thickener component. Examples thereof include metal soap grease and urea grease. Examples of metal soap thickeners include single soap and complex soap. The single soap is a metal soap obtained by saponifying a fatty acid or fat with an alkali metal hydroxide or an alkaline earth metal hydroxide. The complex soap is a compound soap obtained by combining an organic acid having a different molecular structure in addition to a fatty acid used in a single soap. The fatty acid may be a fatty acid derivative having a hydroxy group or the like. The fatty acid may be an aliphatic carboxylic acid such as stearic acid or an aromatic carboxylic acid such as terephthalic acid, but a monovalent or divalent aliphatic carboxylic acid, particularly an aliphatic carboxylic acid having 6 to 20 carbon atoms is used. In particular, monovalent aliphatic carboxylic acids having 12 to 20 carbon atoms and divalent aliphatic carboxylic acids having 6 to 14 carbon atoms are preferably used. Monovalent aliphatic carboxylic acids containing one hydroxyl group are preferred. Examples of organic acids to be combined with complex soap include acetic acid, dibasic acids such as azelaic acid and sebacic acid, benzoic acid, and the like.

The metal of the metal soap thickener may be an alkali metal such as lithium or sodium, an alkaline earth metal such as calcium, or an amphoteric metal such as aluminum, but an alkali metal, particularly lithium, is preferably used.
Carboxylic acid metal salts may be used alone or in combination of two or more. The content of the metal soap thickener may be a desired consistency, and is, for example, preferably 2 to 30% by mass, more preferably 3 to 20%, based on the total amount of the grease composition.
As the urea thickener, for example, a diurea compound obtained by reaction of diisocyanate and monoamine, a polyurea compound obtained by reaction of diisocyanate and monoamine, or diamine can be used.

  Examples of diisocyanates include aliphatic diisocyanates and aromatic diisocyanates. Examples of the aliphatic diisocyanate include diisocyanates having saturated and / or unsaturated linear, branched, or alicyclic hydrocarbon groups. As an example, phenylene diisocyanate, tolylene diisocyanate, diphenyl diisocyanate, diphenylmethane diisocyanate, octadecane diisocyanate, decane diisocyanate, hexane diisocyanate, and the like are preferable. Monoamines include aliphatic monoamines and aromatic monoamines. Examples of the aliphatic monoamine include monoamines having a saturated and / or unsaturated linear, branched, or alicyclic hydrocarbon group. As an example, octylamine, dodecylamine, hexadecylamine, stearylamine, oleylamine, aniline, p-toluidine, cyclohexylamine and the like are preferable. Furthermore, examples of the diamine include aliphatic diamine and aromatic diamine. Examples of the aliphatic diamine include diamines having a saturated and / or unsaturated linear, branched, or alicyclic hydrocarbon group. Specifically, ethylenediamine, propanediamine, butanediamine, hexanediamine, octanediamine, phenylenediamine, tolylenediamine, xylenediamine, diaminodiphenylmethane and the like are preferable.

Urea thickeners may be used alone or in combination of two or more. The content of this thickener is only required to be a desired consistency, and is, for example, preferably 2 to 30% by mass, more preferably 3 to 20% by mass, based on the total amount of the grease composition.
One or two or more kinds of greases arbitrarily selected from these can be blended in any amount, but the content is usually 0.1 to 10% by mass based on the total amount of the composition. Preferably there is.

The surface protective agent composition of the present invention preferably further contains a dye (hereinafter also referred to as “component (h)”) in order to improve the visibility of the applied state.
The component (h) that can be blended in the surface protective agent of the present invention is arbitrary and can be blended in any amount, but the blending amount is usually 0.0001% by mass or more based on the total amount of the composition. It is preferable that it is 1.0 mass% or less. Moreover, in order to further improve the visibility of the application state, the component (h) is more preferably a fluorescent dye.

  Moreover, in the surface protection agent composition of this invention, it is preferable that melting | fusing point is 120 to 150 degreeC.

In the present invention, in the electrical connection structure between the first metal member and the second metal member, at least the first metal member is provided with a surface protective layer formed by applying a surface protective agent composition.
That is, according to the present invention, since the surface protective layer formed by applying the surface protective agent composition is stably held on the surface of the first metal member, the copper (alloy) contained in the first metal member ) And tin plating layer, even when water (particularly an aqueous solution containing ions such as chloride) adheres, water (particularly ions such as chloride) straddle the first metal member and the second metal member. Even when the aqueous solution containing the water adheres, it is possible to suppress the flow of the corrosion current. As a result, according to the present invention, corrosion of the metal member can be suppressed in the electrical connection structure of the metal member.

The second metal member may be made of a metal material having a higher ionization tendency than the first metal member. With such a configuration, for example, even when the second metal member is a member made of aluminum or an aluminum alloy, corrosion of the metal member can be effectively suppressed.
The first metal member may be a first terminal, while the second metal member may be a core wire of an electric wire that is electrically connected to the first terminal. With such a configuration, corrosion of the metal member can be prevented even in a connection structure between a copper terminal and an electric wire having an aluminum (alloy) core wire. For example, even when used in harsh environments that are also affected by moisture in various temperature ranges, such as automobile wire harnesses, lightweight aluminum (alloy) can be used as the core wire. Can be effectively used for weight saving, that is, fuel saving.

The first metal member may be a first terminal, while the second metal member may be a second terminal that fits with the first terminal. With such a configuration, for example, even in a connection structure between the first terminal and the second terminal, corrosion of the metal member can be prevented and leakage current can be suppressed from flowing between the terminals.
The surface protective agent composition of the present invention is preferably semi-solid (gel) in the general use temperature range required to function as a surface protective layer, and is preferably liquid in the coating step. With such a configuration, the surface protective layer can prevent outflow from the surface of the metal member and maintain a corrosion suppressing function in a general operating temperature range, and the first metal member is an electrical terminal. Since the surface protective layer can be easily removed by contact pressure or sliding at the electrical connection portion, the reliability of electrical connection can be improved. Moreover, when the composition is applied at a melting point or higher at which the composition changes from a semi-solid state to a liquid state, the application process can be easily performed and the surface protective layer can be formed uniformly.

<Embodiment 1>
The electrical connection structure 20 of Embodiment 1 which concerns on this invention is demonstrated referring FIGS. 1-3. In the present embodiment, a terminal 21 (an example of a first metal member) including copper or a copper alloy and an electric wire 22 including a core wire 22A (an example of a second metal member) including a metal having a higher ionization tendency than copper are used. This is an electrical connection structure 20.

(Wire 22)
The electric wire 22 is formed by surrounding the outer periphery of the core wire 22A with a synthetic resin insulating coating 22B. As the metal constituting the core wire 22A, a metal having a higher ionization tendency than copper can be used. For example, magnesium, aluminum, manganese, zinc, chromium, iron, cadmium, cobalt, nickel, tin, lead, etc. Or alloys thereof. In the present embodiment, the core wire 22A includes aluminum or an aluminum alloy.
The core wire 22A according to the present embodiment is a stranded wire formed by twisting a plurality of fine metal wires. As the core wire 22A, a so-called single core wire made of a metal bar may be used. Since aluminum or aluminum alloy has a relatively small specific gravity, the terminal-attached electric wire 20 can be reduced in weight as a whole.

(Terminal 21)
As shown in FIG. 1, the terminal 21 includes a wire barrel portion 21B connected to the core wire 22A exposed from the end of the electric wire 22, and an insulation barrel portion formed behind the wire barrel portion 21B and holding the insulating coating 22B. 21A and a main body portion 21C formed in front of the wire barrel portion 21B and into which a male terminal tab (not shown) is inserted.
Further, as shown in FIG. 2, a plurality of recesses 21 </ b> D are formed in the region of the terminal 21 where the core wire 22 </ b> A exposed at the end of the electric wire 22 is connected. When the wire barrel portion 21B is crimped to the core wire 22A, the edge formed at the hole edge portion of the recess 21D comes into sliding contact with the surface of the core wire 22A, and the oxide film formed on the surface of the core wire 22A is peeled off. As a result, the metal surface of the core wire 22A is exposed, and the core wire 22A and the wire barrel portion 21B (terminal 21) are electrically connected by contacting the metal surface with the wire barrel portion 21B.
The terminal 21 is formed by pressing a metal plate made of copper or a copper alloy into a predetermined shape. A tin plating layer (not shown) is formed on the front and back surfaces of the terminal 21. The tin plating layer has a function of reducing the contact resistance between the core wire 22A and the wire barrel portion 21B.
A tin plating layer is not formed on the end face of the terminal 21, and a plate material containing copper or a copper alloy is exposed.

(Surface protective layer 24)
In the present embodiment, as shown in FIG. 1, a surface protective layer 24 is formed on the entire surface of the terminal 21. The surface protective layer 24 is indicated by shading in FIG. That is, in this embodiment, the surface protective layer formed by applying the surface protective agent composition of the present invention to the surface of the terminal 21 including the end face of the terminal 21 (at least the end face of the wire barrel portion 21B). 24 is formed.
Moreover, as shown in FIG.1 (b), the surface protection agent composition may be formed in the whole surface of the terminal 21 and the electric wire 22 connected with it. In this case, the surface protective agent composition can be easily realized by applying the surface protective agent composition to the entire terminal-attached electric wire 20 to which the terminal 21 and the electric wire 22 are connected by means such as dipping, spraying, or brushing.
Furthermore, in front and rear of the wire barrel portion 21B, the core wire 22A is exposed from the wire barrel portion 21B, but the surface protective layer 24 is also formed on the surface of the core wire 22A.
In the present embodiment, the surface protective layer 24, for example, after crimping the terminal 21 to the electric wire 22 to a state as shown in FIG. 3, at least the terminal 21 and the core wire 22A exposed from the electric wire 22 have a melting point or higher. The film can be formed by dipping in a heated surface protecting agent composition and then pulling it up.

  In this embodiment, in the electrical connection structure 20 between the terminal 21 and the electric wire 22, a surface protective layer formed by applying a surface protective agent composition to the terminal 21 containing copper (alloy) on which a tin plating layer is formed. 24 is formed. Therefore, according to the present embodiment, since the surface protective layer 24 is stably held on the surface of the terminal 21, water (so as to straddle the portion of the terminal 21 where the tin plating layer is not formed and the tin plating layer). In particular, even when water (an aqueous solution containing ions such as chloride) adheres, or when water (especially an aqueous solution containing ions such as chloride) adheres across the terminals 21 and the wires 22, the corrosion current is Flow can be suppressed, and corrosion of the terminal 21 and the electric wire 22 can be suppressed in the electrical connection structure 20 between the terminal 21 and the electric wire 22.

<Embodiment 2>
Next, the electrical connection structure 30 of Embodiment 2 which concerns on this invention is demonstrated, referring FIG. This embodiment includes a copper electric wire 32 including a copper core wire 32A (an example of a second metal member) including copper or a copper alloy, and an aluminum core wire 33A (an example of a second metal member) including aluminum or an aluminum alloy. The aluminum wire 33 is connected to the splice terminal 31. The outer periphery of the copper core wire 32A is covered with an insulating coating 32B made of synthetic resin, and the outer periphery of the aluminum core wire 33A is covered with an insulating coating 33B made of synthetic resin. Note that a description overlapping that of the first embodiment is omitted.
In the present embodiment, the copper core wire 32 </ b> A and the aluminum core wire 33 </ b> A are electrically connected by the splice terminal 31. The splice terminal 31 includes a wire barrel portion 31A that is crimped so as to be wound around both the copper core wire 32A and the aluminum core wire 33A. The splice terminal 31 is made of a plate material containing copper or a copper alloy, and a tin plating layer (not shown) is formed on the surface thereof (an example of the first metal member), but a tin plating layer is formed on the end surface thereof. It has not been.

After the copper core wire 32A and the aluminum core wire 33A are connected to the splice terminal 31, the surface protective agent composition can be heated by being heated above the gel point and immersed in a liquid state and then pulled up. .
In the present embodiment, as shown in FIG. 4, at least the surface including the end face of the splice terminal 31 and the surface of the copper core wire 32A and the aluminum core wire 33A exposed from the splice terminal 31 are covered with a surface protective layer. 34 is formed. The surface protective layer 34 is indicated by shading in FIG.
Also in the present embodiment, as in the first embodiment, in the electrical connection structure 30 between the splice terminal 31 and the two types of electric wires 32 and 33, the splice terminal 31 including copper (alloy) on which a tin plating layer is formed is provided. A surface protective layer 34 formed by applying a surface protective agent composition containing a metal affinity compound and a base oil is formed. Therefore, according to this embodiment, corrosion of the splice terminal 31 and the electric wires 32 and 33 can be suppressed.

Hereinafter, the content of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these.
<Surface protective agent composition>
According to the composition shown in Table 1, a surface protective agent composition (Examples 1 to 8) according to the present invention and a composition for comparison (Comparative Examples 1 to 5) were prepared.

(A-1) Mineral oil base oil Kinematic viscosity (100 ° C.): 4.0 mm ² / s
(A-2) Mineral oil base oil Kinematic viscosity (100 ° C.): 11.1 mm ² / s
(A-3) Mineral oil base oil Kinematic viscosity (100 ° C.): 32.0 mm ² / s
(B-1) Isostearyl acid phosphate P content: 6.3% by mass
(B-2) Oleyl acid phosphate P content: 6.5% by mass
(B-3) Di-2-ethylhexyl acid phosphate P content: 9.4% by mass
(C-1) Ethylenebisstearylamide (d-1) Calcium salicylate detergent having an alkyl group having 10 to 20 carbon atoms Ca content: 8.0% by mass, metal ratio: 3.4
(D-2) Calcium salicylate detergent having an alkyl group having 10 to 20 carbon atoms Ca content: 2.3 mass%, metal ratio: 1.1
(E-1) Hindered phenolic antioxidant (f-1) Olefin copolymer Weight average molecular weight: 120,000

<Evaluation>
(Corrosion current evaluation)
A copper wire crimping terminal obtained by crimping a copper wire (copper withstand voltage area of 0.75 mm ² ) to a tin-plated terminal (material: copper alloy) is immersed in a liquid surface protection agent composition heated to 150 ° C. (15 seconds) ), And then pulled up at a speed of 1 cm / sec to create a copper wire crimp terminal with a surface protective layer. The copper wire crimping terminal and the aluminum plate (width 1 cm, plate thickness 0.2 mm) treated in this way are immersed in 5% saline (the copper wire crimping terminal is immersed entirely, and the aluminum plate is immersed 1 cm at the tip) and 50 ° C. The copper wire and the aluminum plate of the copper wire crimping terminal were short-circuited while being heated to 1 hour, and the current flowing between them was measured after 1 hour.
In addition, as an evaluation of the heat resistance of the surface protective agent composition, the copper wire crimp terminal with the surface protective layer prepared as described above was corroded by the same measurement method as described above after leaving at 120 ° C. × 168 hours, which is the heat evaluation condition of JASO D618. The current was measured (corrosion current measured by the above method for untreated copper wire crimp terminals was 50 μA in both the initial stage and after standing at high temperature).
The results are shown in the lower part of Table 1.

(Aluminum wire crimp terminal corrosion evaluation)
An aluminum wire crimping terminal obtained by crimping an aluminum wire (copper withstand area of 0.75 mm ² ) to a tin-plated terminal (material: copper alloy) is immersed in a liquid surface protection agent composition heated to 150 ° C. (15 seconds) ), And then pulled up at a rate of 1 cm / sec to create an aluminum electric wire crimp terminal with a surface protective layer. The aluminum wire crimp terminal thus prepared was subjected to a salt spray test (35 ° C., 5% salt spray) in accordance with JIS 2371 for 168 hours, and the subsequent corrosion state of the aluminum wire was confirmed.
Moreover, as an evaluation of the heat resistance of the surface protective agent composition, the corrosion condition of the aluminum electric wire was determined in the same manner as described above after leaving the aluminum electric wire crimp terminal with the surface protective layer prepared as described above at 120 ° C. for 168 hours. Confirmed by criteria.
The results are shown in the lower part of Table 1.

(Consideration of results)
As shown in Table 1, in Examples 1 to 8, it was confirmed that the corrosion current suppressing effect was maintained even at the initial stage and after heat resistance (after 120 hours at 120 ° C.). Further, it was confirmed that the corrosion of the terminals and the aluminum electric wires could be effectively suppressed even in the terminal corrosion evaluation (after 168 hours of salt spray).
On the other hand, with the lubricating oil of Comparative Example 1 alone, the corrosion current suppressing effect could not be confirmed both in the initial stage and after the heat resistance, and also the corrosion inhibiting effect could not be confirmed in the terminal corrosion evaluation.
In Comparative Examples 2 to 4, one or both of (b) (phosphorus compound) component and (d) (alkali metal or alkaline earth metal salicylate and / or (over) basic salt thereof) component are not included, and corrosion It was confirmed that the inhibitory effect and the terminal corrosion inhibitory effect were inferior to those of the examples.
Moreover, the comparative example 5 is a surface protection agent composition which does not contain (c) (amide) component and is not gelled. As an evaluation result, both the corrosion current suppressing effect and the terminal corrosion suppressing effect were confirmed in the initial stage, but it was confirmed that the effect was lost after heat resistance. This is presumed to be caused by the fact that the surface protective agent composition flows out when left at high temperature when it is not gelled.

Since the surface protective agent composition of the present invention can suppress corrosion due to corrosion current between metals in adjacent dissimilar metal members, it is useful for suppressing corrosion of the metal members in the electrical connection structure of the metal members.
Moreover, since the surface protection agent composition of this invention can improve the corrosion durability of a metal member also in a severe corrosive environment, it is used for the wiring of the transport equipment which requires durability like a wire harness for motor vehicles. be able to.
Furthermore, the electrical connection structure to which the surface protective agent composition of the present invention is applied enables aluminum (alloy), which is effective for reducing the weight of the vehicle, to be used as a material for the core wire of the wire harness. Can be used to reduce fuel consumption and reduce carbon dioxide emissions.

DESCRIPTION OF SYMBOLS 20 Electrical connection structure 21 Terminal 21A Insulation barrel part 21B Wire barrel part 21C Main body part 21D Recessed part 22 Electric wire 22A Core wire 22B Insulation coating 24 Surface protection layer 30 Electrical connection structure 31 Splice terminal 31A Wire barrel part 32 Copper electric wire 32A Copper core wire 32B Insulation Coating 33 Aluminum wire 33A Aluminum core wire 33B Insulation coating 34 Surface protective layer

Claims (28)

(A) In lubricating base oil,
(B) at least one compound selected from the group consisting of a phosphorus compound represented by the following general formula (1) and a phosphorus compound represented by the general formula (2), in terms of phosphorus element, based on the total amount of the composition As 0.005-2.0 mass%,
(In General Formula (1), X ¹ , X ² and X ³ each independently represent an oxygen atom or a sulfur atom, and at least one of them is an oxygen atom, and R ¹¹ , R ¹² and R 3 ¹³ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms)
(In General Formula (2), X ⁴ , X ⁵ , X ⁶ and X ⁷ each independently represent an oxygen atom or a sulfur atom, and at least three of these are oxygen atoms, R ¹⁴ , R ¹⁵ and R ¹⁶ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms)
(C) 0.1 to 40% by mass of the amide compound based on the total amount of the composition,
(D) Alkali metal or alkaline earth metal salicylate having an alkyl group or alkenyl group having 10 to 40 carbon atoms, and / or a (over) basic salt thereof, based on the total amount of the composition, 0 0.005 to 3.0 mass%,
A surface protective agent composition that suppresses the corrosion current between different metal members . (A) a lubricating oil base oil, kinematic viscosity at 100 ° C. is 2 to 50 mm ² / s, the corrosion current suppressing surface protective composition between members of different metals according to claim 1. (B) All of X ⁴ , X ⁵ , X ⁶ and X ⁷ in General Formula (2) of the phosphorus compound represented by General Formula (2) are oxygen atoms, and R ¹⁴ , R at least one of ¹⁵ and R ¹⁶ is a hydrocarbon group having 1 to 30 carbon atoms, according to claim 1 or 2 in the corrosion current suppressing surface protective composition between members of different metals according. (B) All of X ⁴ , X ⁵ , X ⁶ and X ⁷ in General Formula (2) of the phosphorus compound represented by General Formula (2) are oxygen atoms, and R ¹⁴ , R at least one of ¹⁵ and R ¹⁶ is a branched hydrocarbon group having 8 to 30 carbon atoms, according to claim 1 or 2 in the corrosion current suppressing surface protective composition between members of different metals according. (C) the amide compound is at least one represented by the following general formula (3) to (5), inhibiting corrosion current between members of different metals according to any one of claims 1 to 4 Surface protectant composition.
^{R 21 -CO-NH-R 22} (3)
^{R 23 -CO-NH-Y 31} -NH-CO-R 24 (4)
^{R 25 -NH-CO-Y 32} -CO-NH-R 26 (5)
(In General Formulas (3) to (5), R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms. R ²² may be hydrogen, Y ³¹ and Y ³² are each selected from the group consisting of an alkylene group having 1 to 10 carbon atoms, a phenylene group, or an alkylphenylene group having 7 to 10 carbon atoms. 1 to 10 divalent hydrocarbon groups) (C) The amide compound is at least one amide compound represented by the general formulas (3) to (5), and R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ are each individually The surface protective agent composition which suppresses the corrosion current between different metal members of Claim 5 which is an amide compound which is a C12-20 saturated chain hydrocarbon group . (C) the amide compound is at least one amide compound represented by the general formulas (3) to (5), and R ²¹ , R ²³ , R ²⁴ , R ²⁵ And R ²⁶ Are each a saturated chain hydrocarbon group having 12 to 20 carbon atoms, and R ²² The surface protection agent composition which suppresses the corrosion current between the dissimilar metal members of Claim 5 which is an amide compound whose is hydrogen. (C) the amide compound is at least one amide compound represented by the general formulas (3) to (5), and R ²¹ And R ²² , R ²³ And R ²⁴ And R ²⁵ And R ²⁶ The surface protective agent composition which suppresses the corrosion current between the dissimilar metal members of Claim 5 which is an amide compound whose at least any one of these is a C12-20 unsaturated chain hydrocarbon group. (C) The amide compound is a fatty acid amide having a melting point of 20 ° C. to 200 ° C. The surface protective agent composition for suppressing a corrosion current between different metal members according to any one of claims 1 to 8 . (D) The alkali metal or alkaline earth metal salicylate having an alkyl group or alkenyl group having 10 to 40 carbon atoms and / or (over) basic salt thereof has an alkyl group or alkenyl group having 10 to 40 carbon atoms. calcium salicylate, and / or its (over) basic salts, the corrosion current suppressing surface protective composition between members of different metals according to any one of claims 1-9. (D) The alkali metal or alkaline earth metal salicylate having an alkyl group or alkenyl group having 10 to 40 carbon atoms and / or (over) basic salt thereof has an alkyl group or alkenyl group having 10 to 40 carbon atoms. The dissimilar metal member according to any one of claims 1 to 10 , which is an alkali metal or alkaline earth metal salicylate, and / or a (over) basic salt thereof, wherein the metal ratio is 1 to 7.5. Surface protective agent composition that suppresses corrosion current between . Further, (e) an antioxidant, the total amount of the composition, by blending 0.01 to 5 mass%, suppress corrosion current between dissimilar metal member according to any one of claims 1 to 11 A surface protective agent composition. (E) antioxidant, phenolic antioxidant is at least one selected from the group consisting of amine antioxidants suppress surface protective agent corrosion currents between dissimilar metals member according to claim 12 Composition. (E) antioxidant, alkylphenols, is at least one selected from the group consisting of bisphenols, the corrosion current suppressing surface protective composition between members of different metals according to claim 12. Furthermore, the (f) a thickener, based on the total amount of the composition, by blending 0.1 to 20 mass%, suppress corrosion current between dissimilar metal member according to any one of claims 1-14 A surface protective agent composition. (F) a thickener is polyalkyl methacrylate, ethylene -α- olefin copolymers or hydrides thereof, is at least one selected from the group consisting of polyisobutylene and its hydride, heterologous of claim 15 A surface protective agent composition for suppressing a corrosion current between metal members . Furthermore, the (g) grease, the total amount of the composition, formed by 0.1% to 10% blended claim 1 suppressing a surface protective corrosion current between members of different metals according to any one of 16 Agent composition. (G) grease, a lithium grease, corrosion current suppressing surface protective composition between members of different metals according to claim 17. Moreover, (h) by blending a dye, corrosion current suppressing surface protective composition between members of different metals according to any one of claims 1 to 18. A melting point of 120 ° C. to 150 DEG ° C., the corrosion current suppressing surface protective composition between members of different metals according to any one of claims 1 to 19. In an electrical connection structure comprising a first metal member containing copper or a copper alloy and a second metal member different from the first metal member electrically connected to the first metal member , at least the first An electrical connection structure in which a surface protective layer made of a surface protective agent composition for suppressing a corrosion current between different kinds of metal members according to any one of claims 1 to 20 is formed on a surface of the metal member . The electrical connection structure according to claim 21 , wherein the first metal member containing copper or a copper alloy has a tin plating layer formed at least in part. The electrical connection structure according to claim 21 or 22 , wherein the second metal member is aluminum or an aluminum alloy. The electrical connection structure according to claim 21 or 22 , wherein the second metal member is an aluminum electric wire or an aluminum alloy electric wire. In an electrical connection structure comprising a first metal member containing copper or a copper alloy and a second metal member different from the first metal member electrically connected to the first metal member , at least the first 21. A method for inhibiting corrosion of an electrical connection structure, wherein a surface protective layer comprising a surface protective agent composition for inhibiting a corrosion current between different kinds of metal members according to any one of claims 1 to 20 is formed on a surface of a metal member . The surface protection layer of the electrical connection structure according to any one of claims 21 to 24, wherein the corrosion current between the dissimilar metal members according to any one of claims 1 to 20 in a state of being heated to a melting point or higher. An electrical connection structure obtained by dip-coating the surface protective agent composition to be suppressed . Automotive wiring harness using electrical connection structure according to any one of claims 21 to 24 and claim 26. The weight reduction method of the motor vehicle using the wire harness for motor vehicles using the electrical connection structure of Claim 23 or 24 .