TW200813177A - Electroconductivity-controlling agent for cationic electrodeposition coating composition and method for adjusting electroconductivity of cationic electrodeposition coating composition therewith - Google Patents

Abstract

The present invention is intended to provide a technology preventing decrease in an electroconductivity or an throwing power of a cationic electrodeposition coating composition having a lower solid content and/or a lower ash content. Therefore, the present invention relates to: an electroconductivity-controlling agent used for a low solid content type cationic electrodeposition coating composition having 0.5 to 9.0 wt% of solid content of the coating composition, which agent includes an amino group-containing compound having 500 to 20000 of molecular weight and 200 to 500 mmol/100 g of amine value, to adjust an electroconductivity of the composition to 900 to 2000 μS/cm; a method for adjusting an electroconductivity of a cationic electrodeposition coating composition, which includes of: adding an electroconductivity-controlling agent to a low solid content type cationic electrodeposition coating composition having 0.5 to 9.0 wt% of solid content of the coating composition, and adjusting an electroconductivity of the cationic electrodeposition coating composition to 900 to 2000 μS/cm during the above step, wherein the electroconductivity-controlling agent includes an amino group-containing compound having 200 to 500 mmol/100 g of amine value; and the like.

Description

200813177 IX. Description of the Invention: Technical Field of the Invention The present invention relates to a conductive control 5 formulation for a cationic electrodeposition coating composition, and a conductive electrodeposition coating for adjusting the cationic electrodeposition coating using the conductivity control agent " The method of coating the conductivity of a composition. [Prior Art] Background Since a cationic electrodeposition coating layer 10 can form a fine portion and a coating can be automatically and continuously provided even if the object has a complicated shape, the cationic electrodeposition coating layer is widely used as a large-sized one. Primer coatings for articles with complex shapes, especially for car bodies and the like. The cationic electrodeposition coating is carried out by immersing an article to be coated as a cathode, into a cationic electrodeposition coating composition, and applying a voltage. The conventional cationic electrodeposition coating composition is an aqueous coating composition having a solid content of about 20% by weight. The composition is left unmixed, and the components therein are sedimented, for example, a colorant, which causes an electrodeposition bath containing a composition, a precipitate, a cationic electrodeposition coating composition, or a pump. The stirrer is stirred so that sedimentation can be prevented. 20 However, the 'cationic electrodeposition tank is a large-scale equipment in which the body can be immersed in the coating composition. The energy associated with circulating or agitating the composition, the σ used, or the compliance thereof, requires a significant cost. Reducing or omitting such cycles or mixing, Southern contributes to energy savings in cationic electrodeposition coatings. Therefore, it is effective to use a cationic electrodeposition coating composition under enthalpy sedimentation or minimal sedimentation, in particular, a cationic electrodeposition coating composition having a lower solid content or a lower ash content. Such cationic electrodeposition coating compositions have been studied. Japanese Patent No. 3, JP-A-2004-231989 (Patent Document 1) discloses an environmentally-friendly electrodeposition coating having a cationic electrodeposition coating composition having a cationic electric/esthetic coating composition of 3 to 10% by weight. The ash content of the pigment and the solid content of 5 to 12% by weight. This cationic electrodeposition coating composition is useful because this composition has a small amount of sedimentation, and thus the cost of disposal on agitation or lapse is reduced. Disadvantageously, the 10 reduction in the solids content of the coating composition reduces the conductivity of the composition. It also enables the "deep plating ability, deterioration" of the composition. The deep plating ability herein is the ability to form a coating onto a fine part on an object during electrodeposition coating. For those skilled in the art, It is known that an appropriate adjustment of the conductivity of the coating composition can provide an ideal deep plating ability. Patent Document, Jp_A_2〇〇4_15 269627 (Patent Document 2) discloses the relationship between the conductivity of the coating composition and the ability of the deep clock. The cationic electrodeposition coating composition described in this document contains a ruthenium-modified epoxy resin, and thus the composition requires control of film resistance. The amine resin of the base resin in the cationic electrodeposition coating composition has been studied. [See Jp-A-2005_232397 (Patent Document 3), JP-A-7-150079 (Patent Document 4).] Patent Document 3 discloses that the amine valeric acid (base resin) has an amine price of 20 to 60. MgKOH/g (i.e., 35.7 to 107.0 mmol/100 g) is desirable. Patent Document 4 also discloses that the cation value of the cationic electrodepositable resin is from 3 to 200 mgKOH/g (i.e., 5.3 to 356 6 200813177 mmol/ L〇〇g) is also within the scope of thinking / thinking. The price range is conventional and is very low in nature. Patent Document 1: JP-A-2004-231989 Patent Document 2: JP-A-2004-269627 5 Patent Document 3 · JP-A-2005-232397 Patent Document 4 JP-A-7-150079 SUMMARY OF THE INVENTION [The present invention is intended to solve the problem of a cation-washed 10-pack coating composition having a lower solid content and/or a lower ash content, which is combined with a conventional cationic electrodeposition coating composition. The present invention tends to have reduced conductivity. The present invention provides a reduction in conductivity of a cationic electrodeposition coating composition having a lower solid content and/or a lower ash content and preventing deep plating of the composition. TECHNICAL FIELD OF THE INVENTION Accordingly, the present invention provides a conductivity control agent for a low solid content cationic electrodewashing coating composition, the coating composition comprising a solid content of the coating composition 0.5 to 9.0% by weight, the controlling agent comprises an amine group-containing compound having a molecular weight of 500 to 20,000 and an amine value of 200 to 500 mmol/100 g to adjust the conductivity of the coating composition to 9 to 20 2000 # S/cm. In addition to being In addition to the cationic epoxy resin, curing agent and colorant of the film-forming component, the cationic electrodeposition coating composition contains the conductivity control agent of the present invention as an emulsion, and the emulsion can be actually added as the third group. The amine-containing compound used as the conductivity control agent may be an amine modified by the amine. The surface-modified epoxy dragon is preferably "fat, wherein the epoxy group has utilized an amine. Compound modification. The acryl resin which is modified with _(4) _ amine-modified is preferably a propionate resin having an amine compound modified by a dioxy group. The epoxy resin can be a double-presence type, the first: r: butyl sulphate - butyl oxime phenol type, novolac phenolic > lacquer resin type or phenol novolak novolak resin, and can have 5 〇〇 to The number average molecular weight of 20000. The present invention also provides a low solid content cationic electrodeposition coating composition comprising a solid content of from 5% to 9% by weight of the coating composition, which comprises from 200 to 500 mm 〇i/100 g The amine-valent amine-containing compound-containing conductivity control agent, and the conductivity of the composition is from 9 Å to 2,000 // S/cm 〇 15 The present invention further provides a method for adjusting a cationic electrodeposition coating composition. A method of electrical conductivity comprising the steps of: adding a conductivity control agent to a low solids content cationic electrodeposition coating composition, the coating composition having a solids content of from 0.5 to 9.0 by weight of the coating composition %, and 20, during the above steps, adjusting the conductivity of the cationic electrodeposition coating composition to 900 to 2000 μS/cm, wherein the conductivity control agent comprises an amine having an amine valence of 200 to 500 mmol/100 g Base compound. The present invention still further provides a method for supplying a conductivity control agent to a cationic electrodeposition coating composition, comprising the steps of: 200813177 supplying a conductivity control agent to a low solid content type cationic electrodeposition coating composition' The coating composition has a solid content of from 0.5 to 9.0% by weight of the coating composition, and during the above steps, adjusting the conductivity of the cationic electrodeposition coating composition to 900 to 2000 #S/cm, wherein The conductivity control agent includes an amine group-containing compound having an amine mussel of 200 to 500 mmol/100 g. The present invention can be solved with a lower ash content type and/or a lower solid content type by adding a specific 10 conductivity control agent for cationic electrodeposition coating composition to the cationic electrodeposition coating composition. The problems associated with cationic electrodeposition coating compositions, such as the reduced conductivity of cationic electrodeposition coating compositions and their reduced deep clocking ability. BRIEF DESCRIPTION OF THE DRAWINGS 15 Fig. 1 is a perspective view showing an embodiment of a case applied to evaluate deep plating ability; and Fig. 2 is a cross-sectional view schematically showing a specific example of a method for evaluating a deep clock ability. Reference letter 20 10 ·• Box 11 to 14: Zinc phosphate treated steel plate 15 ·· Opening 20 : Electrodeposition tank 21 : Electrodeposition coating composition 9 200813177

22: opposite electrode [Embodiment; J. BEST MODE FOR CARRYING OUT THE INVENTION 10 15 20 According to the present invention, the conductivity controlling agent for the cationic electrodeposition coating composition includes 200 to 500 mmol/l 〇〇g The amine-containing compound of the amine price. Any amine group-containing compound can be applied as the conductivity control agent for the cationic electrodeposition coating composition of the present invention as long as the amine group-containing compound has an amine valence in the above-defined range. In general, an amine-modified epoxy resin and an amine-modified acrylic resin are preferred conductivity control agents. The conductivity control agent for a cationic electrodeposition coating composition of the present invention can be neutralized with an acid if necessary. The acid value is preferably from 25 Å to 45 Å mmol/100 g', more preferably from 3 Å to 400 mmol/100 g. If the amine price is less than 200 mmol/l〇〇g, the amount of the conductivity control agent to be added is increased, so that the liquid cation electrodeposition coating composition having a lower solid content can be used for abating. Causes inferior resistance. If the amine price exceeds the lion, g~ has problems such as reduced deposition power and deep mineral capacity. In this case, it is also possible to have compatibility with zinc steel sheets. The amine-containing compound of the present invention as an amine group-containing compound 'resin alcohol amine amount for use as a conductivity control agent for a cationic electrodeposition coating composition. One or two =! The low molecular weight or high molecular weight may be aminated, for example, by a group of amines (IV). Examples of the acrylic acid-B-amino compound having a low molecular weight μ / / branch and an amine modified include monoethyl, monoethanolamine, dimethylbutylamine and the like. The present invention preferably employs an amine-containing compound having an a knife, and an epoxy resin and an amine-modified resin. The amine-modified epoxy resin can be obtained by utilizing an aminated sulfonate resin, that is, an epoxy group therein. It is preferred that the genus m-tree is 500 to 20 Å ... "special, 4 money resin, which is preferably an epoxy resin having a molecular weight of 500 to 20 _ = gas tree 鸠 type 5 epoxy resin, Tributyl phthalate-type epoxy tree bismuth line: such as double, • lacquer type epoxy resin and nail _ type secret varnish tree = _ Jing in these epoxy resins, particularly ideal is oxygen resin and ¥Saki-type varnish resin type epoxy resin. It is intended that these epoxy resins are commercially configurable, and for example, = 10 brain 438, linear secret varnish resin «oxy resin, which can be purchased from Dow Chemical The company (the Dow Chemical c〇mpany ) ' 曰本; YDCN-703, f transformation secret clear _ epoxy resin, can be said from TohtoKaseiCo.'Ltd., etc. Resin modification of polyester polyols, polyfluorinated polyols, and mono- succinyl benzene resins. Alternatively, epoxy resins can be subjected to bond extension treatment, including the reaction of epoxy groups with diols or diacids. Examples of the amine-modified acrylic resin include a homopolymer of dimethylaminoethyl methacrylate which is an amine group-containing Monomer, without any modification, or copolymerization of dimethylaminoethyl methacrylate with other polymerizable monomers, without any modification, and modified homopolymer of glycidyl methacrylate The glycidyl group is modified with an amine compound, or a modified copolymer of glycidyl methacrylate and other polymerizable monomers, wherein the glycidyl group is modified with an amine compound. The amine group can be introduced into the epoxy group. Based on epoxy resin or acrylic resin 11 200813177 Compounds include primary amines, secondary amines, tertiary amines such as butylamine, octylamine, diethylamine, dibutylamine, monomethylbutylamine, monoethanolamine, two Ethanolamine, methyl-ethanolamine, triethylamine hydrochloride, N,N-dimethylethanolamine acetate, a mixture of diethyl disulfide and acetic acid, and a secondary amine which is a blocked 5 primary amine, for example Diketimine of aminoethylethanolamine, diketimine of diethylhydroamine, etc. One or more amines are readily available. As described above, Amine modified epoxy resin and The amine-modified acrylic resins each preferably have a number average molecular weight of from 500 to 20,000. If the number average molecular weight is less than 5 Å, the corrosion resistance may decrease, the deep plating ability may decrease, and the tendency may be resigned. The compatibility of the steel sheet, but the reasons are unknown. If the number average molecular weight exceeds 20,000, it may cause a poor finished appearance. The above-mentioned conductive control agent according to the present invention is applied to the cationic electrodepositor 15 to coat the composition 'the coating The coating composition includes, but is not limited to, a lower solid content cationic electrodeposition coating composition having a solid content of from 5 to 9.0. The conductivity control agent of the present invention can also be applied to have a weight of about 2% by weight. A conventional cationic electrodeposition coating composition of solid content. In this case, the electrical conductivity of the conventional cationic electrodeposition coating composition can be lowered, and 20 electrodeposition coating using the coating composition may provide insufficient deep recording capability. With regard to these deficiencies, the addition of the conductivity control agent of the present invention to the conventional cation electrodeposition coating composition allows the conductivity to be controlled within an appropriate range, which ensures sufficient supply of deep ship capacity. The amine-modified epoxy resin to be used in the present invention or the amine-modified 12 200813177 can be neutralized with a neutralizing acid in advance. The neutralizing acid includes inorganic acids and organic acids such as hydrochloric acid, nitric acid, phosphoric acid, sulfanilic acid, citric acid, acetic acid, lactic acid and the like. Electrodeposition coating material 5 Regarding the conductivity control agent of the present invention for the erbium ion electrodeposition coating composition, the control sheet to be added to the cation electrodeposition coating composition can be adjusted. Preferably, the electrodeposition coatings the conductivity of the composition. The yang

The ion electrodeposition coating composition includes a cationic epoxy resin and a curing agent, and if necessary, a colorant and/or an additive. These components are described separately below.

The cationic epoxy resin which can be applied to the present invention includes an amine-modified oxime resin. The cationic epoxy resin is generally produced by opening a ring gas guide of all double-type epoxy resins by using an active hydrogen compound capable of introducing a cationic 15 group, or by opening a part of the epoxy ring by using another active hydrogen compound. And then the remaining epoxy ring is opened using an active hydrogen compound that can introduce a cationic group. The cationic resin included in the cationic electrodeposition coating composition preferably has an amine value of 50 to 200 mmol/100 g which is less than the amine price of the conductivity control agent (i.e., 200 to 500 mmol/100 g). . If the amine price is lower than 50 mm 〇 l / l 〇 0 g, it is difficult to ensure the dispersibility of the cation-modified epoxy resin to water. If the amine price exceeds 200 mmol/100 g, the water-repellent hygiene of the resulting coated film may deteriorate. Therefore, these examples are not preferred. Typical examples of the two-age type epoxy resin include bisphenol A type epoxy resin sausage and 13 200813177 bisphenol F type epoxy resin. The products available on the market in the former include

Epikote 828 (manufactured by Yuka-Shdl Ep〇xy c〇·, Ltd., epoxy equivalent: 180 to 190), Epikote 1001 (same manufacturer, epoxy equivalent: 450 to 500), Epikote 1010 (same manufacturing) Commercially available, epoxy equivalents: 3〇〇〇5 to cents (10)) and the like, as well as commercially available products of the latter include Epikote 807 (same manufacturer, epoxy equivalent: 17〇) and the like. An epoxy resin containing a sulfonium ring represented by the following chemical formula and disclosed in jp_A_5_3〇6327 can be used as a cationic epoxy resin: ch-ch2-or· / -o-ch2-ch /c~° \ ^NrR-N CH-CHr〇-R· , ch2 xch2

10 wherein 仏 means a residual group formed by removing a glycidyloxy group of diglycidyl ethoxylate 'R' means a residual group formed by removing one of the isocyanate groups in the diisocyanate compound, And 11 means positive integer. This is because the obtained coating layer has excellent heat resistance and residual resistance. An example of a method for introducing σ acetophenone into a lyooxyl resin includes: 15 using a heating and maintaining temperature in the presence of a basic catalyst to occlude the polyepoxide with a lower alcohol which has been treated with, for example, methanol The closed polyisocyanate brewing reaction, as well as the lower alcohol which is a by-product from the vaporization of the oxime, is obtained. These epoxy resins can be modified with suitable resins such as polymer polyols, polyether polyols, and monofunctional alkyl phenols. Further, the epoxy resin may extend the bond by using a reaction of an epoxy group with a diol or a dicarboxylic acid. Desirably, the ring of the epoxy resin is opened by the active hydrogen compound, and the amine has a valence of 5 Å to 2 〇〇 mmol/l 〇〇g after the ring is opened, and preferably, the primary amine group The proportion is 5 to 50%. Active hydrogen compounds which can introduce cationic groups include acid salts, sulfides and acid mixtures of primary amines, secondary amines and tertiary amines. The primary amine, the secondary amine 5 or/and the tertiary amine salt is used as an active hydrogen compound capable of introducing a cationic group, so that a primary amine group, a secondary amine group or/and a tertiary amine group can be prepared. Epoxy resin.

Specific examples include butylamine, octylamine, diethylamine, dibutylamine, methylbutylamine, monoethanolamine, diethanolamine, N-methyl-ethanolamine, triethylamine hydrochloride, ίοN,N-dimethyl- Ethanolamine acetate, a mixture of diethyldisulfide and acetic acid, and a secondary amine which is a blocked primary amine such as ketimine and diketimine of amine ethylethanolamine. Diethylenediamine and the like. One or more amines are readily available.

Curing dance I t 川 伞 伞 仍 咧 咧 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 仍 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化 固化As used herein, = vinegar means "a curricular type of polyisocyanate having 2 or more isocyanate groups in the molecule, such as an aliphatic type, an alicyclic type, Aromatic and aromatic-aliphatic. The special (4) sub-inclusion includes the aromatic diisocyanate, the example of the iso- oxic acid ester (TDI), - ! Motian a ^ ^ ... a sour acid, with 3 to 12 carbon atoms r :: wide Vinegar's such as hexamethyldiiso-acid _ "pyridyl diisocyanate" and lysine diisocyanate; having 5 to 18 = 15 200813177 one atom of alicyclic diisocyanate, such as 1,4 -cyclohexanediisoxamic acid (CDI), isophorone diisocyanate (IPDI), 4,4,-dicyclohexylmethane monoisocyanate (hydrogenated MDI), methylcyclohexane diisocyanate, tetraisoa Propyldicyclohexyl-4,4'-diisocyanate and 1,3-diisocyanate methylcyclohexane 5 (hydrogenated XDI), hydrogenated TDI and 2,5- or 2,6-bis(isocyanacic acid Methyl) _ secondary [2·2·1] octane (also known as norbornane diisocyanate); aromatic diisocyanate with aromatics, such as xylene diisocyanate (XDI) and tetramethyl benzene Diisocyanate (TMXDI); an upgraded product of such isocyanates (a urethane product, a carbodiimide, a urethodione, a urethoimine, Digestive and/or isocyanuric acid The product of ester modification), etc., etc. may be used singly or in combination of two or more thereof. By reacting polyisocyanate g with a polyvalent alcohol by a ratio of NCO/OH of 2 or higher The obtained adduct or prepolymer can also be used as a curing agent, 15 the polyvalent alcohol such as ethylene glycol, propylene glycol, trimethyl propylene or hexane triol. As the polyisocyanate, preferably aliphatic poly Isocyanate and alicyclic polyisocyanate because the obtained coating film has excellent water repellency. Particularly preferred examples of the aliphatic polyisocyanate and the alicyclic polyisocyanate include hexamethylene diisocyanate, hydrogenated TDI, hydrogenated MDI, hydrogenated XDI, 20 IPDI, norbornane diisocyanate, and other dimers (biurets) and terpolymers (isocyanurates), etc. Addition of blocking agent to polyisocyanate group, stable at room temperature However, when heated to a dissociation temperature or higher, a free isocyanate may be regenerated. 16 200813177 An example in which the curing process is desirably performed at a lower temperature (for example, no more than 16 ° C) Preferably, for example, using ε - Indoleamine-type capping agent, such as formic acid, acetic acid, acetone, methyl ethyl ketone, and dimethyl ketone And a cyclic blocking agent of 5 cyclohexanone oxime as a blocking agent. The content of the binder containing the cationic epoxy resin and the curing agent is generally 25 to the total solid content of the electrodeposition coating composition. 85 wt%, preferably 40 to 70 wt%. Colorant 10 The electrodeposition coating composition to be applied to the present invention may include a conventionally used colorant. Examples of usable colorants include conventional use. Inorganic pigments, for example, dyed pigments such as titanium white, carbon black and iron oxide; filler pigments such as sedite, talc, aluminum silicate, calcium carbonate, mica and clay, such as zinc phosphate, filling Acid iron, aluminum phosphate, calcium sulphate, 15 zinc phosphite, zinc cyanide, zinc oxide, aluminum tripolyphosphate, zinc molybdate, aluminum molybdate, calcium molybdate, and aluminum phosphomolybdate, phosphomolybdic acid Aluminum, barium hydroxide, barium oxide, barium carbonate, barium nitrate, barium benzoate, barium citrate, The anti-bismuth. Eclipse toner and the like. — The content of the colorant is 20 liters, preferably 1 to 35% by weight, preferably 10 to 30% by weight, based on the total solids of the electrodeposition coating composition. I material - the current s color is used as a component of the electrodeposition coating composition, the color material 1 is used to form a high concentration of the paste, and the tree month called the color material dispersion resin Pick up 'initial dispersion in aqueous media. Since the colorant is in the form of a powder, 17 200813177 it is difficult to disperse the colorant into a uniform low concentration state for the electrodeposition coating composition by one step. In general, this paste is referred to as a pigment dispersion paste. The pigment dispersion paste can be prepared by dispersing a colorant and a colorant dispersion resin varnish in an aqueous medium. In general, the pigment dispersion varnish 5 includes a cationic or nonionic surfactant having a low molecular weight, and cationic polymerization of, for example, a modified epoxy resin having a quaternary ammonium group and/or a tertiary sulfhydryl group. Things. The aqueous medium includes ion-exchanged water, water containing a small amount of alcohol, and the like. In general, the colorant-dispersed resin varnish in the toner-dispersed paste has a solid content of 5 to 40 parts by weight, and the toner-dispersed paste has a solid content of 10 to 30 parts by weight. The above-mentioned color-dispersed resin varnish and coloring matter are mixed in an amount of from 1 to 1 part by weight based on 1 part by weight of the solid resin. Next, the colorant is dispersed in a conventional dispersing device such as a ball mill and a sand mill to produce a toner dispersion paste, wherein the toner has a predetermined uniform particle size. The solid content of the above cationic electrodeposition coating composition according to the present invention must be from 0.5 to 9.0% by weight of the coating composition. If the solid content of the coating composition is less than 0.5% by weight, cationic electrodeposition coating cannot be performed. On the other hand, if the solid content of the coating composition exceeds 9% by weight, a precipitate of 20 color component contained in the cationic electrodeposition coating composition is left alone without being disturbed. Therefore, these examples are not preferred. The p-electrodeposition coating composition of the electrodeposition coating composition can be prepared by dispersing a cationic epoxy resin, a curing agent, and a toner dispersion paste in an aqueous medium. In general, aqueous media can include intermediates that improve the dispersibility of cationic epoxy resins (iv). 7 中 18 200813177 ..., the agent includes inorganic acids and organic acids such as hydrochloric acid, nitric acid, phosphoric acid, formic acid, acetic acid and lactic acid. The amount of neutralizing agent used is an amount sufficient to achieve a neutralization ratio of at least 20%, preferably 30 to 60%. The amount of curing agent used should be an amount sufficient to react with the primary, secondary and/or tertiary amine groups in the cation 5 ionic epoxy resin or functional groups such as hydrogen groups containing active hydrogen during the curing process. It is possible to provide an excellent cured coating film. In general, the cationic epoxy resin/curing agent has a weight ratio range (based on solids containing hydrazine:) of from 90/10 to 50/50, preferably from 80/20 to 65/35. The 10 € deposition coating composition may include, for example, a tin compound of dibutyltin dilaurate and dibutyltin oxide as a catalyst, or a urethane cracking catalyst which has been conventionally used. Since these catalysts are preferably substantially #compounds, the amount of catalyst used is preferably from 1 to 5% by weight based on the amount of the blocked polyisocyanate compound. 15 € deposited coating composition may include six conventionally used for coating compositions

Additives such as water compatible organic solvents, surfactants, antioxidants: UV absorbers and colorants. ~ 20 Low ash content. The cationic package deposition coating composition of the present invention is not particularly limited, and the coating composition includes the above-mentioned main components. Cationic electrodeposition % of the material, according to the invention of the invention, the material is: = low solid content type. The cationic electrodeposition coating composition of the present invention can be a cationic electrodeposition coating composition which has a lower solid content and has a lower than conventional coating composition (i.e., about 2% by weight). It is from 0.5 to 9% by weight, more particularly from 3 to 9% by weight. If the solid content is less than 0.5% by weight, in the composition, there is an undesired precipitation of the color component without agitation. On the other hand, if the solid content exceeds 9% by weight, it is acceptable, and the addition of the conductivity control agent may be ineffective in adjusting the conductivity of the 5 cation electrodeposition coating composition. The method for reducing the solid content of the cationic electrodeposition coating composition includes reducing the colorant content in the coating composition, wherein the ash content is lowered, and herein, the ash content is calculated by the following formula: [(ash) The solids containing 10 parts by weight of the solids of the coating composition for coating the residue after burning of the composition)] xlOO. Therefore, the present invention can be applied to a cationic electrodeposition coating composition of a lower ash content type. The conventional cationic electrodeposition coating composition has an ash content of 15 to 40% by weight. Therefore, the lower ash content type cationic electrodeposition coating composition preferably has an ash content of 2 to 7% by weight, more preferably 3 to 515 % by weight. Preferably, the article to be subjected to electrodeposition coating and to which the electrodeposition coating composition is to be applied is a previously surface-treated conductor which is treated, for example, by zinc immersion or spray coating. Alternatively, the surface of the object may be left untreated. The conductor, as used herein, means any material which can be a cathode when electrodeposited, and preferably, but not particularly limited, a metal substrate. The conditions for electrodeposition coating are the same as those conventionally used for any electrodeposition coating. The applied voltage can vary significantly from iV to hundreds of volts. Current densities typically range from about ί amps/m 2 to 16 amps. 20 200813177 psi/m 2 During the electrodeposition coating, the current density tends to decrease. After electrodeposition coating in accordance with the method of the present invention, the resulting coating is subjected to conventional bake processing at elevated temperatures, including baking in a burner or oven or under an infrared heat lamp. In general, the baking temperature 5 can vary from about 140 ° C to about 180 ° C. The article coated with the composition by the % ion electrodeposition coating according to the present invention was finally cleaned and baked by water to form a cured electrodeposition coating film on the article. The coating process of the invention can be costed. According to the present invention, the above-mentioned conductivity controlling agent is added to the liquid cationic electrodeposition coating composition to ensure the conductivity of the liquid coating composition. As described above, the cationic electrodeposition coating composition having a lower solid content is conventionally less conductive than the conventional liquid cationic electrodeposition coating composition (i.e., having a solid content of about 2% by weight). . Therefore, the addition of the specific conductivity control agent of the present invention to the cationic electrodeposition coating composition can compensate for this deficiency. By increasing the amine valence of the cationically modified epoxy resin as a coating film forming component, the conductivity of the composition can be adjusted to an appropriate range so as to ensure the deep plating ability of the composition. However, if the amine value of the cation-modified epoxy resin of the composition exceeds 2 〇〇 mm 〇 i / 100 g, the water repellency of the resulting 20-coated film may deteriorate. This condition is not preferred. The necessary conductivity for the desired deep plating capability is 900 to 2000//S/cm. The conductivity control agent of the present invention is added to a liquid solid electrodeposition coating composition of a lower solid content type, and the conductivity of the electrodeposition coating composition can be controlled and adjusted within a desired range. A preferred lower limit of conductivity is 1000//S/cm and a preferred upper limit 21 200813177 • 1800 #S/cm. If the conductivity is less than 900/zS/cm, there is a problem that the desired deep mineral capacity cannot be ensured. If the conductivity exceeds 2 Å//S/cm, there is a problem that the coating film formed on the zinc steel sheet is often insufficient (that is, a so-called gas pinhole). In this context, conductivity can be measured at a liquid composition temperature of 25 ° C using a commercially available conductivity measuring instrument. The amount of the conductivity controlling agent of the present invention to be added to the cationic electrodeposition coating composition is not particularly limited as long as the desired conductivity can be ensured. The specific example of the amount is from 0.5 to 30% by weight, preferably from 1 to 30% by weight, more preferably from 1 to 15% by weight, based on the solid content of the coating composition. The bitter star is less than 0.5% by weight, which is acceptable and may result in insufficient conductivity. Alternatively, if the amount exceeds 50% by weight, it is also acceptable, and the increase in conductivity may be outweighed by the amount added. As described above, the lower solids content cationic electrodeposition coating composition having the desired adjusted conductivity may be a lower ash and solids containing 15 amount of cationic electrodeposition coating composition, and preferably Can have a guaranteed % deep money ability. Even though this cationic electrodeposition coating composition is used in a coating process in which many articles can be continuously applied, the process must supply a coating forming component into a tank containing the cationic electrodeposition coating composition. In this case, the conductivity of the cationic electrodeposition coating composition in the bath may not deviate from the desired range of 900 to 2000/zS/cm of the present invention. If the conductivity does not exceed 900//S/cm, it may be necessary to add the conductivity control agent of the present invention to the tank containing the cationic electrodeposition coating composition so as to maintain the solid content in the range of 0.5 to 9.0% by weight. And adjusting the conductivity of the cationic electrodeposition coating composition in the range of 900 to 2000 / zS / cm. 22 200813177 EXAMPLES The present invention is described in further detail based on the following examples. Those skilled in the art will appreciate that the invention is not limited to the embodiments. In this example, "parts" and "%" are based on weight unless otherwise stated. 5 Example A-1 295 parts of decyl isobutyl ketone (hereinafter abbreviated as μιβκ), 37·5 The thioglycolamine and 52.5 parts of diethanolamine were fed to a flask equipped with a reflux condenser and a stirrer. The temperature of the mixture was maintained at 100 ° C with stirring. 205 parts of phenolic novolac resin epoxy Resin, which was purchased from Tohto Kasei Co., Ltd. under the trade name YDCN-703, was gradually added to the mixture. After the completion of the addition of the resin, the reaction was carried out for 3 hours. The modified resin has a molecular weight of 21 Å and an amine price of 340 mmol/l 〇〇g (MEq (b)). Example A-2 15 Add 5 parts by weight of formic acid and 1254.5 parts of deionized water to 140 parts of the amine-based modified resin solution prepared in Example A-1. The temperature of the mixture was maintained at 8 ° C for 30 minutes by stirring. The organic solvent was removed under reduced pressure to obtain a liquid composition. Conductivity Control Agent A (solid content: 7.0%). 20 Example B-1 255 parts of VHBK and 75 parts of mercaptoethanolamine were fed to a flask equipped with a reflux condenser and a stirrer. The temperature of the mixture was maintained at 100 ° C by stirring. 180 parts of novolak resin type ring Oxygen resin, which is commercially available from The Dow Chemical Company, day 23 200813177, under the trade name DEN-438, is gradually added to the mixture. After completion of the addition of the resin, the reaction is carried out for 3 hours. The base modified resin has a molecular weight of 1000 and an amine price of 390 mmol/l 〇〇g (MEQ(B)). Example B-2 5 14 parts of sulfamic acid and 1247 parts of deionized water are added to 14 〇. In the amine-modified resin solution prepared in Example B-1, the temperature of the /ester compound was maintained at 80 C for 30 minutes by stirring, and the organic solvent was removed under reduced pressure to obtain a liquid composition. Conductivity Control Agent B (solid content: 7·〇%). 10 Example C-1 50 parts of methyl isobutyl ketone (ΜΙΒΚ) was fed to a reflux condenser, a nitrogen introduction tube, and a dropping solution. Flask with a funnel and stirrer. Stirring to maintain the temperature of the mixture A mixture of 1 part of glycidyl methacrylate and 2 parts of azobisisobutyronitrile (aibn) 15 was continuously added dropwise to the flask by using a dropping funnel at 10 ° C. For 2 hours, the temperature of the mixture was maintained at 100 ° C for 30 minutes by stirring, and then, 5 hours of MIBK and 5 parts of AIBN were added dropwise to the flask in 1 hour. The reaction was further carried out for 1 hour by stirring. Repress the reaction. Example C-2 2〇 47. 5 parts of MIBK and 5·8 parts of methylethanolamine were fed to a flask equipped with a reflux condenser and a stirrer. The mixture was kept at 100 ° C by means of mixing. 205 parts of the reaction mixture prepared in Example CM were gradually added to the mixture. After completion of the addition of the reaction mixture, the reaction was carried out for 3 hours. The resulting amino-based modified resin has a molecular weight of 98 〇 Q and an amine price of 45 〇 24 200813177 • mmol/100 g (MEQ (B)). r Example C-3 25 2 parts of lactic acid and 1234.8 parts of deionized water were added to an amine-based modified resin solution prepared in 14 Å of the wounds of Example C-2. The temperature of the mixture was maintained at 8 ° C for 30 minutes by means of a transfer. The organic solution was removed under reduced pressure to obtain a conductivity control agent c (solid content: 7.0%) for the liquid composition.

• Comparative Example D 9 463. 4 parts of deionized water and 13.5 parts of formic acid were added to a glass frit 10 cups. Stir the mixture. With stirring, 23.1 parts of dimethylethanolamine (molecular weight: 89) was gradually added to the mixture to obtain a conductivity control agent D for the liquid composition (active ingredient content: 7%; amine price of the active ingredient (MEQ (MEQ ( B)) : 740 mmol/100 g). Preparation Example 1: Preparation of the composition of the cation green electrodeposition coating composition 15 Preparation Example 1-1: Amine modified epoxide _ _ 92 parts of 2,4-/2,6· benzene benzene Isocyanate (2,4-type/2,6-form = 8/2, by weight ratio), 95 parts of methyl isobutyl ketone (hereinafter abbreviated as MIBK) and 0.5 part of dibutyl laurate The crucible was fed to a flask equipped with a stirring, cold and cold, a nitrogen introduction tube, a thermometer, and a dropping funnel. 20 Using a scramble, '21 parts of methanol was added dropwise to the reaction mixture. The reaction was carried out at room temperature. The reaction temperature rose to 6 ° C due to the heat of the reaction. The reaction was allowed to continue for 30 minutes. Five parts of ethylene glycol mono-2-ethylhexyl ether was added dropwise to the reaction mixture by using a dropping funnel. Further, 53 parts of the propylene oxide (5 mol) adduct of bisphenol A was added to the reaction mixture 25 200813177. The reaction is carried out mainly in the range of 6 〇t: to the pit. The reaction was continued until the absorption peak of the isocyanate group was determined to be: Next, an epoxy resin having an epoxy equivalent of 188 parts by weight of 188, which has been synthesized from a mixture of A and epichlorohydrin according to a known method, is added to the reaction mixture 5. The reaction temperature was raised to 125 °C. 1.0 part of stupid methyl dimethylamine was added to the mixture. The reaction was carried out at 纟13叱, and the ring equivalent was adjusted to 410.曰 Next, add 61 parts of a and 33 parts of octanoic acid to the mixture. The reaction was carried out at 12 ° C to allow an epoxy equivalent of 1190, and 10 followed by cooling of the reaction mixture. A solution of 11 parts of diethanolamine, 24 parts of N-ethyl-ethanolamine, and 25 parts by weight of 79% by weight of ketimine of ketimine was added to the reaction mixture. The reaction was carried out at 11 Torr for 2 hours. The reaction mixture was diluted with hydrazine (nonvolatile content: 8% by weight). The resulting amine modified epoxy resin had a solids 15 resin content of 8 %. JL Preparation Example I-2 Isocyanate curing section of L_F4· was prepared. 1250 parts of diphenylmethane isocyanate and 266.4 parts of MIBK were fed into a reaction tank. The mixture was heated to 8 (rc. 2.5 parts of dibutyltin dilaurate was added to the mixture. 226 parts of ε • caprolactam dissolved 2 was dissolved in 944 wounded ethylene glycol T_(butyi ceii〇s〇 Ive), a solution was obtained, and the solution was added dropwise to the mixture over 2 hours at 80 ° C. The reaction mixture was further heated at 100 ° C for 4 hours, and it was confirmed that it was identified as an isocyanate group by IR spectrum measurement. The absorption peak disappeared. The reaction mixture was allowed to cool. 336.1 parts of MIBK was added to the reaction mixture to obtain a blocked 26 200813177 isocyanate curing agent (glass·conversion temperature: 〇.〇: colorant dispersed blush, 偌 222.0 parts) Isophorone diisocyanate g (hereinafter abbreviated as IPDI) was added to a flask equipped with a stirrer, a condenser, a nitrogen introduction tube, and a temperature of 5. A 39·1 part of MIBK was added to the tank to Diluting the ipdi, and then adding 0.2 parts of dibutyltin dilaurate to the reactants. Next, the temperature was raised to 50 ° C, and 131 was added dropwise with stirring over 2 hours under a dry nitrogen atmosphere. ·5 copies of 2_B Lithohexanol. With appropriate cooling, the reaction temperature was maintained at 50 ° C, and IPDI (solid resin content: 90.0%) semi-blocked with 2-ethylhexanol 10 was obtained. Next, 87 2 parts were sequentially placed. Dimethylethanolamine, 117.6 parts of 75% aqueous lactic acid solution, and 39.2 parts of ethylene glycol monobutyl ether were added to a suitable reaction tank. The reaction mixture was stirred at 65 ° C for about 3 minutes to obtain a fourth stage. Quarterizing agent. 15 Next, 710.0 parts of EPON 829 (available from Shell Chemical Company's bisphenol A type epoxy resin; epoxy equivalent · 193 to 203) and 289.6 parts of the double A feed To a suitable reaction tank. The reaction mixture is heated to 15 to 160 ° C under a nitrogen atmosphere. The initial exothermic reaction is carried out. The reaction mixture is maintained at 150 to i6 ° C for about 1 hour, at 20 and then cooled to 12 〇. 498.8 parts of pre-prepared 2-diethylhexanol semi-blocked IPDI (as MIBK solution) was added to the reaction mixture. The reaction mixture was maintained at 11 Torr to 12 ° C for about 1 hour. Then, add 463.4 parts of ethylene glycol monobutyl ether. Cool the mixture. 85 to 95 ° C. After homogenization, a pre-prepared quaternizing agent is added to the reaction 27 200813177 mixture. - The reaction mixture is maintained at 85 to 95 t: to adjust the acid value to 4. 964 wound deionized water The reaction mixture was added to suppress the quaternary reaction of the epoxy double-branched A tree to obtain a colorant dispersion resin having a quaternary ammonium salt structure (solid resin content: 50%). 5 Preparation Example 1_1: Toner Dispersion Paste 100 parts of the colorant dispersion resin prepared in Preparation Example 1-3, 1 (10) parts of titanium oxide, and 100.0 parts of ion-exchanged water were fed into a sand mill. The color material was dispersed to adjust the particle size to not more than 10 #!!!, and a toner dispersion paste (solid content··50%) was obtained. 10 Separation Example lj: Preparation of Emulsion The amine-modified epoxy resin prepared in Preparation Example 1-1 was uniformly mixed with the blocked isocyanate curing agent prepared in Preparation Example 1-2 (epoxy resin/curing) Agent = 80/20, based on solid content). Glacial acetic acid was added to the mixture so that the ratio of (MEQ (A)) · (mg equivalent of acid) / (100 15 g of resin solid content) was 30. Ion exchanged water was slowly added to the mixture to dilute the mixture. The MIBK' was removed under reduced pressure to obtain an emulsion (solid content··36%). Comparative Example 1 319 parts of the emulsion prepared in Preparation Example 1-5, 133 parts of 20 colorant dispersion paste, 543 parts of ion-exchanged water, 2 parts of 1% by weight aqueous solution of barium acetate, and 3 parts of oxidation were mixed. Dibutyltin was obtained as an electrodeposition coating composition F (solid content··2%). The solid content of the cationic electrodeposition coating composition included a pigment having a concentration of 23% by weight. Herein, the solid content of the coating composition is calculated by the following formula (according to JIS K 5601): 28 200813177 [(residual mass after heating the composition for 30 minutes at TC) 〆 (original

The quality of the composition 篁)] X100 (%). The obtained electrodeposition coating composition F was used as Comparative Example 1 according to the actual conditions. The conductivity of the liquid composition was 1600 #S/cm 〇5. Comparative Example 2 158 parts of the emulsion prepared in Preparation Example i_5, 8 parts of the colorant dispersion paste, 831 parts of ion-exchanged water, and 2 parts were mixed. An aqueous solution of 1% by weight of acetic acid and 1 part of dibutyltin oxide were used to obtain an electrodeposition coating composition (solids containing ϊ · 7%). The colorant concentration was 5% by weight. The resulting electrodeposition coating 10 composition G was used as Comparative Example 2 according to the actual conditions. The liquid composition has a conductivity of 890 // S/cm. Example 1 6 parts of the conductivity controlling agent a prepared in Example A-2 was added to 1000 parts of the previously prepared electrodeposition coating composition G to adjust the conductivity of the composition 15 to 1200 VS/cm to obtain electrodeposition. Coating composition h. The electrocaloric coating composition was used as Example i. Example 2 8 parts of the conductivity controlling agent B prepared in Example B-2 was added to 1000 parts of the previously prepared electrodeposition coating composition G to adjust the conductivity of the composition 20 to S/cm. Electrodeposition coating composition I. Electrospray coating composition I was used as Example 2. Example 3 Three parts of the conductivity controlling agent C prepared in the example c-3 were added to 1000 parts of the previously prepared electrodeposition coating composition 以 to adjust the conductivity of the composition 29 200813177 to 1100 # s/cm 4 . Electrodeposition coating composition J was obtained. Electrospray coating composition J was used as Example 3. Example 4 400 parts of ion-exchanged water was added to 1000 parts of the previously prepared electric 5 deposition coating composition G to reduce the solid content (7%) to 5%. This step reduces the conductivity (890//S/cm) of the composition to 640# s/cm. Eight parts of the conductivity controlling agent A prepared in Example A-2 was added to the composition to adjust the conductivity of the composition to 1100 //s/cm to obtain an electrodeposition coating composition K. The electrodeposition coating composition K was used as Example 4. 10 Comparative Example 3 One part of the conductivity controlling agent D prepared in Comparative Example D was added to 1000 parts of the electrodeposited coating composition G prepared in advance to adjust the conductivity of the composition to 1200/zS/cm. Electrodeposition coating composition L. The electrodeposition coating composition L was used as Comparative Example 3. The cationic electrodeposition coating composition prepared in the examples and the comparative examples and the cured cationic electrodeposition coating layer having the compositions were evaluated according to the following methods. Deep plating ability The deep plating ability of the cationic electrodeposition coating composition was evaluated by the so-called four 2 crate method. In particular, as shown in Fig. i, four steel plates U to 14 (JISG3141 spcc sD) treated with zinc phosphate (SURFDINE SD-_, available from Nippon Paint KK) are spaced at intervals of 20 mm. The vertical and parallel placement, and the lower and bottom planes of the two side planes are covered by an insulating material such as an adhesive tape to prepare the box 10 in 30 200813177. The steel plates 11 to τ ^ I have an opening 15 of 8 mm. phi on the lower side except for the plate 14. A 4 liter cationic electrodeposition coating composition was filled into the ethylene glycol bath to obtain a first electrodeposition bath. As shown in Fig. 2, the case 1 is used as the object to be coated, and is immersed in the electrodeposition tank 2〇 filled with the electrodeposition coating composition U. Herein, the coating composition 21 penetrates only into the inside of the tank 1 through the opening 15. The composition 21 was agitated by a magnetic stirrer (not shown in Fig. 2). The steel sheets u to 14 were electrically connected, and the opposite electrode 22 was placed at a position 15 μm apart from the steel sheet 11 closest to 1 。. A voltage is applied between the steel sheets 11 to 14 serving as a cathode, and the opposite electrode 22 is used as an anode, whereby the steel sheet is subjected to cationic electrodeposition coating. After applying the voltage, the voltage was increased for 5 seconds, allowing the thickness of the coating formed on the surface a of the steel sheet n to be 15/zm. Next, a conventional electrodeposition process was carried out in which the applied voltage was maintained for 1 75 seconds or, in the case of a brief electrodeposition, for 115 seconds. After the electrodeposition coating, the steel sheets were rinsed with water, and the coating was cured under the 丨chuan for 25 minutes, and then cooled in the air. The thickness of the coating formed on the surface a of the steel sheet which is adjacent to the opposite electrode 22 is measured. Next, the thickness of the coating layer 20 formed on the surface G of the steel sheet 14 farthest from the opposite electrode 22 is measured. The deep plating ability of the cationic electrodeposition coating composition was evaluated by the ratio of the coating thickness on the surface G / the thickness of the coating on the surface A (ratio G/A). The evaluation criteria are as follows: Excellent: G/A > 50% (indicated by grade A) Bad: G/A = 50% or G/A < 50% (indicated by grade B). 31 200813177 ιν and zinc panel increase the voltage to 220 V in 5 seconds, and apply for 175 seconds to process the treated plated steel plate, which has been prepared by alloying and melting to obtain on the steel plate. Electrodeposition coating. Rinse the steel plate with water, and bake at η〇(: 25 minutes. Observe the resulting coating and evaluate it as follows. 0 Grade A: Excellent condition of coating without defects. Grade B: The coating is slightly defective. Bad condition level C: bad condition in which the coating has significant defects 1 〇 flatness (appearance) The steel sheet is placed in parallel with the bottom of the deposition tank without agitation, the deposition tank containing a cationic electrodeposition coating composition, and Next, electrodeposited and baked steel sheets were obtained. A plate having a cured electrodeposition coating thereon was obtained. The appearance of the coating was visually evaluated as follows. Grade A: Excellent appearance without problems Grade B: Rough texture due to slight precipitation of the colorant Poor appearance grade C · · Poor appearance conductivity with pigment precipitation 20 cation electrodeposition coating composition prepared in each of the examples and comparative examples

The conductivity of the material was measured using a conductivity measuring instrument (CM_305' available from DKK-TOA CORPORATION) at a temperature of the liquid composition of 25 °C. 32 200813177

Table 1

Example 1 2 3 4 Conductivity Control Agent ABCA Conductivity Control Agent MEQ(B) (mmol/100 g) 340 390 450 340 Conductivity Controlling Agent Molecular Weight 2100 1000 9800 2100 Neutralizing Acid Amino Acid Sulfonic Acid Lactic Acid Solid content (%) of the coating composition 7 7 7 5 Color content (%) 5 5 5 5 Conductivity (Ms/cm) of the coating composition 1200 1300 1100 1100 Deep plating ability AAAA compatible with the steel plate Sexual AAAA Flatness AAAA 33 200813177 Table 2

Comparative Example 1 2 3 Conductivity Control Agent Without D Conductivity Control Agent MEQ(B) (mmol/100 g) - - 740 Conductivity Controlling Agent Molecular Weight - 89 Neutralizing Acid No Acid-Free Coating Composition Solid Content (%) 20 7 7 Colorant content (%) 23 5 5 Conductivity (Ms/cm) of the coating composition 1600 890 1200 Deep plating ability ABB and steel plate compatibility AAC Flatness CAA

Regarding the cationic electrodeposition coating compositions of Embodiments 1 to 4, each of them contains the conductivity controlling agent of the present invention, and the conductivity of the compositions is within an appropriate range. Therefore, these compositions have no shortage of deep mineral capacity and coating appearance. The cationic electrodeposition coating composition of Comparative Example 1 had a conventional solid content of 200813177, i.e., 20% by weight. The conductivity of this composition is within the scope of the invention. However, this composition has a high solid content and, therefore, this composition provides poor flatness. The cationic electrodeposition coating composition of Comparative Example 2 had a solid content of 7% by weight, which was a lower solids content. The electrodeposition coating composition has insufficient conductivity and thus low plating ability. Regarding the cationic electrodeposition coating composition of Comparative Example 3, wherein the amine group-containing compound has been introduced into the cationic electrodeposition coating composition of Comparative Example 2, the amine value of the amine group-containing compound deviates from the range defined by the present invention. The composition has a deep plating ability and compatibility with steel sheets. 10 [Simple Description of the Drawings] Fig. 1 is a perspective view showing an embodiment of a case applied to evaluate the deep plating ability; and Fig. 2 is a cross section showing a specific example of a method for evaluating the deep plating ability. Figure. 15 [Description of main component symbols] 10 boxes A surface 11 treated with zinc lanthanum zinc plate B surface 12 coated with zinc sulphate treated plate C surface 13 treated with acid slabs to determine the surface of the plate 14 surface treated with zinc lanthanum zinc E Surface 15 Opening F Surface 20 Electrodeposition groove G Surface 21 Electrodeposition coating composition Η Surface 22 Reverse electrode 35

Claims (1)

200813177 X. Patent Application Range: _ i A conductivity control agent for a low solid content cationic electrodeposition coating composition, the coating composition having a solid content of 0.5 to 9.0% by weight of the coating composition, The controlling agent includes an amine group-containing compound having a molecular weight of from 5 to 20,000 and an amine price of from 200 to 500 mmol/100 g to adjust the conductivity of the composition to 9 to 2000 # S/cm 〇 2 The conductive control agent of claim 1, wherein the amine-containing compound is an amine-modified epoxy resin or an amine-modified acrylic tree 1 resin. 3. The conductive control agent of claim 2, wherein the amine-modified epoxy resin is an epoxy resin in which an epoxy group has been modified by an amine compound. 4. The electroconductive control agent according to claim 2, wherein the amine-modified acrylic resin is a propionic acid resin having an epoxy group modified with an amine compound. 5. The conductive control agent according to item 3 of the patent application, wherein the cyclic eucalyptus resin is a bisphenol type, a tert-butyl catechol type, a novolak type resin type or a cresol novolac type resin type. 20 6· A low solid content cationic electrodeposition coating composition, the coating composition having a solid content of 〇_5 to 9% by weight of the coating composition, the composition comprising a conductivity control agent The conductivity control agent contains an amine group-containing compound having an amine value of 200 to 500 mmol/100 g, and the composition has conductivity of 9 Å to 2000//8/〇111. 36 200813177 7. A method for adjusting the conductivity of a cationic electrodeposition coating composition, comprising the steps of: adding a conductivity control agent to a low solid content type cationic electrodeposition coating composition, the coating The solid content of the composition is 0.5 to 9.0% by weight of the coating composition 5, and during the above steps, the conductivity of the cationic electrodeposition coating composition is adjusted to 900 to 2000 #S/cm, wherein the conductivity The controlling agent includes an amine group-containing compound having an amine value of 200 to 500 mmol / 100 g. 10 8. A method for supplying a conductivity control agent to a cationic electrodeposition coating composition, comprising the steps of: supplying a conductivity control agent to a low solid content type cationic electrodeposition coating composition, the coating composition The solid content is 0.5 to 9.0% by weight of the coating composition, and 15 the conductivity of the cationic electrodeposition coating composition is adjusted to 900 to 2000//S/cm during the above steps, wherein the conductivity The sex control agent includes an amine group-containing compound having an amine value of 200 to 500 mmol / 100 g. 37