JPS624077B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resin composition for electrodeposition coatings that uses liquid polybutadiene as one of its raw materials. Conventionally, liquid polybutadiene has been mainly used in electrodeposition paints by anodic electrodeposition, and is particularly used in industrial paints for automobiles and the like. For information on these methods,
Special Publication No. 51-24532, No. 51-150597, No. 150597, No. 52
-102347, Japanese Unexamined Patent Publication No. 47-3436, and many other methods are known. These all relate to resins made for anode electrodeposition. However, in recent years, a method for producing cathodic electrodeposition paint resin has been established, and it has become possible to obtain a coating film with particularly excellent corrosion resistance, and there is a growing momentum to replace the anodic electrodeposition method using liquid polybutadiene. This is because the main components of the resin used for cathodic electrodeposition are a resin composition consisting of an adduct of an epoxy compound and an amine compound and a blocked organic polyisocyanate, and therefore the resulting coating film has a high crosslinking density. Since the coating film has strong adhesion to the iron plate, it is considered to have excellent corrosion resistance. On the other hand, regarding the method of using liquid polybutadiene as a resin for cathode electrodeposition paint,
16048, 53-8629, 51-119727, 52-
No. 147638, No. 53-63439, etc.
The problem with these methods is that liquid polybutadiene can only be cathodically electrodeposited, and the essential drawback of liquid polybutadiene, which is poor adhesion to iron plates compared to epoxy resin systems, has not been improved. It is a point. The adhesion between this paint film and the iron plate is one of the evaluation items in the corrosion resistance test, but it is extremely important for automotive paint films and is generally called the cellophane tape peel test. Japanese Unexamined Patent Publication 1973-
16048, No. 53-8629, No. 51-119727, etc., the electrodeposition resin obtained by the method described in Publications No. 16048, No. 53-8629, No. 51-119727, etc. was tested again, and the coating electrodeposited on a dull steel plate was maintained for less than 72 hours in a tape peel test. . In addition, in the paint industry, electrodeposition paint resins based on conjugated diene polymers have poor tape peeling test performance in corrosion resistance tests, regardless of whether they are cathodic electrodeposition or anodic electrodeposition. It is known that: In order to improve these drawbacks, a resin composition for cathode electrodeposition coatings was prepared by mixing an aminated product of an epoxy compound, an imidized product of a maleic compound of liquid polybutadiene, and blocked tolylene diisocyanate. As a result, the compatibility with the epoxy compound is poor, and the baked paint film has uneven island-like particles attached to it, and the painted surface becomes extremely uneven. It was discovered that the corrosion resistance also rapidly deteriorates as the temperature increases. The present inventors have developed a compound (B) having a specific alcoholic hydroxyl group and/or a secondary monoamine compound (C) and a maleated product of liquid polybutadiene (A).
(hereinafter sometimes referred to as adduct) and/or partially amidated product (D) is used to carry out an addition reaction between the remaining carboxyl group and the epoxy compound. It has been found that a uniform transparent resin liquid can be obtained without gelation even when the number is 2 or less. The resin composition for electrodeposition coatings obtained by aminating this composition and mixing it with blocked organic diisocyanate and neutralizing it with acid is electrodeposited, washed with water, and then baked to form a uniform coating film. Summer. The corrosion resistance of the so-called clear coating film, which does not contain pigments, was over 100 hours at a film thickness of 20μ. In this way, a uniform resin liquid can be obtained, corrosion resistance is improved, and the drawbacks of conventional cathode electrodeposition resins based on epoxy resins, such as poor impact resistance and bending according to the Erichsen test, have been significantly improved. We have already applied for a patent. Thereafter, the present inventors proceeded with studies to improve various physical properties of the coating film, such as further improvement of corrosion resistance, and arrived at the present invention. That is, in the present invention, (a) an alcoholic hydroxyl group selected from an aliphatic alcohol, an amino alcohol having a tertiary amino group, and a hydroxyl group-containing methacrylic ester is added to (A) a maleated liquid polybutadiene having a molecular weight of 500 to 5,000. The compound (D) obtained by reacting the compound (B) and/or the secondary monoamines (C) to perform partial esterification and/or partial amidation is converted into an epoxy compound (E), A compound (H) obtained by reacting with an epoxy modifier (F) selected from saturated and unsaturated aliphatic dicarboxylic acids, aromatic dicarboxylic acids, acrylic acid and cyanoacetic acid and secondary monoamines (G) and ( (b) A resin composition for electrodeposition paint containing a completely blocked organic polyisocyanate as a main component, and (2) the above compound (H).
This is a resin composition for electrodeposition coatings whose main component is a reaction product obtained by reacting a partially blocked organic polyisocyanate with a partially blocked organic polyisocyanate. Furthermore, the present invention provides a resin composition for electrodeposition coatings in which the mixture of (1) and the reaction product of (2) are neutralized with an organic carboxylic acid. The present invention will be explained in detail below. The liquid polybutadiene used in the present invention is a butadiene polymer having a number average molecular weight of 500 to 5,000.
The microstructure of double bonds in the polybutadiene does not matter, and 1,4-type bonds and 1,2-type bonds may be included in any proportion. In addition, depending on the type of polymerization initiation or termination of the butadiene polymer, OH type, COOH group, halogen group, or
Also included are butadiene polymers having a functional group such as an amino group represented by the general formula NR ₂ (R represents hydrogen or a hydrocarbon group having 1 to 20 carbon atoms). It also includes butadiene polymers chain-transferred with toluene, α-olefin, etc. The maleated product of liquid polybutadiene is obtained by subjecting liquid polybutadiene to an addition reaction with maleic acid or its anhydride, and among these, the anhydride is preferable. Compounds with alcoholic hydroxyl groups used in addition or dehydration condensation reactions with maleides (A)
(B) is an aliphatic alcohol, an amino alcohol having a tertiary amino group, and a methacrylic ester having an OH group. Examples of aliphatic alcohols include methanol, ethanol, propanol, allyl alcohol, butanol, amyl alcohol, isoamyl alcohol, neopentyl alcohol, hexyl alcohol, isohexyl alcohol, n-octyl alcohol, 2-ethylhexyl alcohol, nonyl alcohol, decyl alcohol, In addition to primary alcohols such as dodecyl alcohol, myristyl alcohol, oleyl alcohol, and stearyl alcohol, 2-propanol, 2-butanol, 3-methyl-2-butanol, 2-pentanol, 3-
Pentanol, 2-hexanol, 3-hexanol, 4-heptanol, 2-octanol, 2
- Secondary alcohols such as nonanol and 2-tridecanol, and tertiary alcohols such as t-butanol. Furthermore, ethylene glycol derivatives such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monopropyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, ethylene glycol monoacetate, and ethylene glycol monoacrylate , ethylene glycol monoethers and monoesters such as ethylene glycol monomethacrylate. Examples of methacrylic acid esters having a hydroxyl group include 2-hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate. Examples of amino alcohols having a tertiary amino group include dimethylaminoethanol, diethylaminoethanol, dipropylaminoethanol, dibutylaminoethanol, dihexylaminoethanol, dioctylaminoethanol, N
-Hydroxyethylmorpholine, diphenylaminoethanol, dibenzylaminoethanol, dimethylaminopropanol, diethylaminopropanol, N-hydroxyethylimidazoline and other compounds having a tertiary amino group and an alcoholic OH group in the molecule. Secondary monoamines (C) include dialkylamines such as dimethylamine, diethylamine, dipropylamine, sibutylamine, dipentylamine, dihexylamine, and dioctylamine; dialkanolamines such as dimethylolamine, diethanolamine, and dipropanolamine;
They include phenothiazines and the like, but dialkylamines are preferred. Here, amino alcohols having a tertiary amino group are listed as examples of the compound (B) having an alcoholic hydroxyl group used in the addition or dehydration condensation reaction with the maleate (A). The present inventors have previously proposed a partial amide compound obtained by reacting maleated liquid polybutadiene with N,N-dimethylaminopropanediamine or, for example, diethylaminoethanol, in Comparative Example 1 in the specification of Japanese Patent Application No. 54-2525. When the free carboxylic acid group is partially esterified with epoxy resin, the reaction system shows a gel-like state, and the reaction rate based on the carboxylic acid group is 24%.
It was shown that On the other hand, the same specification states, ``In the reaction between the modified polybutadiene and the epoxy resin, the tertiary amino group in the polybutadiene acts as a catalyst and homopolymerization of the epoxy resin proceeds, resulting in gelation of the reaction system. However, as a result of detailed study by the present inventors, it was found that
It was found that homopolymerization by amino groups was not the only cause. That is, by reacting an adduct (A) of liquid polybutadiene and maleic acid or its anhydride with, for example, N,N-diethylaminoethanol, the partially aminoesterified product obtained by adding the excess carboxyl group and epoxy resin to each of the partial aminoesters. The factors that cause the reaction system to gel during the reaction are:
As mentioned above, there are cases where the tertiary amino group of the partially imidized product or partially aminoesterified product acts as a homopolymerization catalyst for epoxy groups, and the density of surplus carboxyl groups in the partially imidized product or partially aminoesterified product contributes to gelation. There may be cases where this is the case. The question is which of these two is dominant, but the present inventors have investigated and found that the latter carboxyl group density is more dominant under commonly used reaction conditions. .
When introducing functional groups by maleation reaction, distribution of the number of introduced groups is unavoidable, and there are many chances that a polyfunctional component that acts as a crosslinking agent is present. Based on these points of view, the present inventors have determined that, by using favorable reaction conditions that do not involve gelation at all, such as reducing the number of carboxyl functional groups, increasing the amount of epoxy groups, and adding an epoxy group-reactive third component,
It was found that the purpose could be fully achieved. On the other hand, the above-mentioned homopolymerization catalytic action of the tertiary amino group on the epoxy group depends on the reaction conditions, especially the temperature, and the same group is a strong catalyst for promoting the ring-opening addition reaction between the carboxyl group and the epoxy group. It turns out that there is. As a result of the discovery of these facts, in the reaction between the adduct (A) and the adduct of N,N-dialkylamino alcohol, which was exemplified as an inconvenient system in Japanese Patent Application No. 54-2525, and an epoxy resin, under the reaction conditions. Although gelation was observed, this is not an essential problem, and not only can the purpose of the present invention be fully achieved, but this system also has the characteristic of imparting cationic properties to the conjugated diene polymer site. . Therefore, the characteristics of this system have been fully utilized to achieve the desired performance improvement, leading to the present invention. The epoxy compound (E) includes an epoxy compound having one or more epoxy groups per molecule. Epoxy compounds containing one epoxy group per molecule include phenyl glycidyl ether,
These include epichlorohydrin, propylene oxide, ethylene oxide, styrene oxide, isobutylene oxide, allyl glycidyl ether, glycidyl acrylate, and glycidyl methacrylate. Examples of polyepoxides containing two or more epoxy groups in one molecule include epoxy compounds obtained from bisphenol A and epichlorohydrin,
Epoxy compounds obtained from hydrogenated bosphenol A and epichlorohydrin or bisphenol A and β-methylepichlorohydrin, polyglycidyl ethers of novolak resins, polyglycidyl ethers of polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin or trimethylolpropane. These include ethers, polyglycidyl esters of polycarboxylic acids such as adipic acid, phthalic acid, or dimer acids, and epoxidized products of natural drying oils and semi-drying oils. As the epoxy modifier (F) which is reacted with these epoxy compounds (E) to form an adduct, saturated and unsaturated aliphatic dicarboxylic acids, aromatic dicarboxylic acids, or acid anhydrides thereof are used. For example, aliphatic saturated dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and succinic anhydrous, and aliphatic unsaturated dicarboxylic acids include maleic acid. , fumaric acid, citraconic acid, mesaconic acid, glutaconic acid, itaconic acid, allylmalonic acid, isopropylidene succinic acid, acetylene carboxylic acid, succinic anhydride, maleic anhydride, and citraconic anhydride. Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, phthalic anhydride, and 1 to 2 halogen atoms, CN groups, and OH groups.
H atoms are substituted. In addition, cyanoacetic acid and acrylic acid can be used as monocarboxylic acids. As the basic amino compound (G) which is reacted with these epoxy compounds to form an adduct, secondary monoamines are used. Examples include alkylamines such as diethylamine dipropylamine, dialkanolamines such as dipropanolamine and diethanolamine, and monoamines such as cyclohexylamine, pyrrolidine, and morpholine. m or p as organic polyisocyanate
- Fats such as phenylene diisocyanate, 4,4-diphenylmethane diisocyanate, 2,4- or 2,6-tolylene diisocyanate, m- or p-xylylene diisocyanate, hexamethylene diisocyanate, dimer acid diisocyanate, isophorone diisocyanate group or aromatic diisocyanates and adducts of one or more of these diisocyanates with polyols such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, and also trimers of the aforementioned diisocyanates. Polyisocyanates such as Examples of blocking agents for organic polyisocyanates include methanol, ethanol, propanol, butanol, hexanol, heptanol,
Octanol, nonyl alcohol, decanol,
Dodecanol, hexadecanol, allyl alcohol, crotyl alcohol, propargyl alcohol, cyclohexanol, benzyl alcohol,
aliphatic or aromatic monoalcohols such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, acetoxime,
These include oximes such as methyl ethyl ketone oxime, and active hydrogen compounds such as acetylacetone and ethyl acetoacetate. Examples of acrylic esters and methacrylic esters having a hydroxyl group include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate,
2-hydroxypropyl methacrylate and the like can also be used. Ethanolamine, diethanolamine, dimethylolamine, dipropanolamine, N,N-dimethylaminoethanol, N,N
-diethylaminoethanol, N,N-dibutylaminoethanol, N-methyldiethanolamine, N-ethyldiethanolamine, N-propyldiethanolamine, N-butyldiethanolamine, N-methyldimethylolamine, N-ethyldimethylolamine, N-propyldiethanolamine Alkanolamines such as methylolamine are also used as blocking agents. The acids required to neutralize the mixture (1) or the reaction product (2) include formic acid, acetic acid, propionic acid, oxic acid, hexylic acid, 2-ethylhexylic acid, lactic acid,
Organic carboxylic acids such as hydroxyacetic acid and oxalic acid, or inorganic acids such as phosphoric acid, hydrochloric acid, sulfuric acid, and boric acid may be used. The adduct (maleide) (A) of liquid polybutadiene and maleic acid or its anhydride is synthesized by a known method. That is, it can be synthesized by mixing liquid polybutadiene and maleic acid or its anhydride and reacting at 50 to 300°C for 30 minutes to 20 hours. When an anti-gelling agent is required,
It is added to the reaction system in an amount of 0.01 to 10% by weight, preferably 0.01 to 2% by weight. The amount of maleic acid or its anhydride used is such that the content in the resulting adduct (A) is 3 to 50% by weight, preferably 5 to 25% by weight. The sum of the number of moles of the compound (B) having an alcoholic hydroxyl group to be added or condensed to the adduct (A) and the number of moles of the amine is preferably 0.01 to 10 moles per mole of maleic acid or its anhydride. Add so that the amount is 0.1 to 2 moles. At this time, the proportion of the amine (C) in the sum of the number of moles of the compound (B) having an alcoholic hydroxyl group and the number of moles of the amine (C) is 0 to 100%. The reaction is carried out at 0 to 250°C, preferably 30 to 180°C, for 30 minutes to 5 hours. Unreacted amines and the like may be recovered, or the reaction may be continued as is if there is no adverse effect on subsequent reactions. Compound (D) obtained by reacting the adduct (A) with a compound having an alcoholic hydroxyl group (B) and/or secondary monoamines (C) to perform partial esterification and/or partial amidation
is 20 to 80% of the total acid value of adduct (A), preferably 45
~65% is partially esterified and/or partially amidated, with the remaining carboxyl groups subsequently reacted with the epoxy resin. The adduct (D) thus obtained is reacted with an epoxy compound (E) and an epoxy modifier (F), and part or all of the excess epoxy groups of the reactant are converted into secondary amines (G). Compound (H) is synthesized by reaction. In this case, when reacting with the adduct (D), the epoxy compound (E) is modified with an epoxy modifier (F) and then reacts with the adduct (D). Case where three modifiers (F) are reacted simultaneously or adduct (D) and epoxy compound
There are cases where the epoxy modifier (F) is reacted after reacting (E). In some cases, an epoxy compound (E) that already contains an OH group may be used as is, or a low molecular weight epoxy compound (E) with few OH groups may be partially opened with an epoxy modifier (F). After OH groups are generated by a ring reaction, the partially blocked organic polyisocyanate (I) can be subjected to an addition reaction, and then reacted with the adduct (D). In this case, the secondary amine (G) may be added during the reaction with (E) and (F), or may be added together with the adduct (D). In the present invention, the use of the epoxy modifier (F) greatly contributes to improving various properties of the final resin, such as adhesion to the base material, smoothness, gloss, and chemical resistance. The dicarboxylic acids are used in an amount of 0.1 to 1.0 equivalent per equivalent of the epoxy group of the epoxy compound. By selecting the reaction ratio, it is possible to introduce functional groups based on each compound into the epoxy compound and increase the molecular weight at the same time. In the addition reaction between the carboxyl group of the adduct (D) and the epoxy compound or modified epoxy compound,
In a system in which amines are present, the addition reaction of the amines to the epoxy resin can be carried out in parallel. The reaction between the carboxyl group and the epoxy group is carried out by a known method, for example, at a temperature of 0 to 250°C, preferably 30 to 180°C, in the presence of a base catalyst. In addition, the reaction between amines and epoxy groups ranges from 0 to
It is carried out at 200°C, preferably 30-180°C. In addition, the reaction between amines and epoxy groups ranges from 0 to
It can be easily carried out at 200°C, preferably 30-150°C. Further, if necessary, if there is an excess of epoxy groups, a reaction with a monocarboxylic acid is performed subsequently. The amount of amines at this time is the composition (H)
The amine value (expressed in mg of KOH equivalent to mg of hydrochloric acid required to neutralize 1 g of resin) is 10~
150, preferably 25 to 100. The amount of monocarboxylic acids used is equivalent to or less than the amount of excess epoxy groups. Partially blocked organic polyisocyanate (I) having free isocyanate groups is used in composition (H)
The amount is preferably from 5 parts by weight to 300 parts by weight, preferably from 10 parts by weight to 100 parts by weight. The method for producing the partially blocked organic polyisocyanate is such that the amount of organic polyisocyanate is 0.6 to 2 mol, preferably 0.8 to 1.2 mol, per 1 mol of the blocking agent. The reaction temperature is 0 to 200°C, preferably 20 to 140°C. In addition, the reaction between this partially blocked organic polyisocyanate and composition (H) was carried out at 20 to 140°C for 10 minutes to 10 minutes.
Time is done. The completely blocked organic polyisocyanate is a completely blocked organic polyisocyanate obtained by reacting all the isocyanate groups of the organic polyisocyanate with a blocking agent. The fully blocked organic polyisocyanate is used in an amount of 5 to 200 parts by weight, preferably 10 to 100 parts by weight, per 100 parts by weight of composition (H). In addition to the resin composition of the present invention, a pigment or various additives such as a surfactant or a wetting agent can be dispersed to prepare an aqueous electrocoat dispersion. Examples of pigments include iron oxide, lead silicate, lead oxide, strontium chromate, carbon black, titanium white, talc, kaolin, barium sulfate, cadmium yellow, cadmium red,
Chromium yellow etc. can be used. The content of pigment in the electrodeposition paint is usually expressed as the ratio of the amount of pigment to the amount of resin. Typically in the practice of this invention 0.01
A pigment to resin ratio of ~5:1 is used. Further, other additives are mixed and used in an amount of 0.01 to 4% by weight of the resin solid content. When the electrodeposition paint containing the electrodeposition resin composition of the present invention as a resin component is electrodeposited, it is deposited on an iron plate connected to a cathode to form a film. After washing this with normal water
Baking hardens at 150-250°C, preferably 170-200°C. During curing, the blocking agent in the blocked organic polyisocyanate in the resin dissociates and evaporates, and the generated isocyanate groups chemically bond to the OH groups in the resin composition of the present invention and at the same time, 2
Since curing occurs simultaneously due to the crosslinking reaction between the heavy bonds, it provides even better properties. The resin composition of the present invention exhibits excellent corrosion resistance on untreated steel sheets, and in particular has excellent resistance, that is, adhesion, in the tape peeling test of the corrosion resistance test. It is excellent. Examples are shown below, but the present invention is not limited thereto. Reference Example 1 Production example of maleated liquid polybutadiene (1) One flask equipped with a stirrer, thermometer, cooling tube, and inert gas introduction kettle, with a number average molecular weight of 1700 and a double bond microstructure of cis-1,4
540 g of liquid polybutadiene with 75% structure, 24% trans-1,4 structure, and 1% vinyl structure, viscosity of 630 centipoise at 20°C, iodine value (Wiss method) 420, 60 g of maleic anhydride and iron naphthenate (Fe= 5%) was charged and reacted at 190° C. for 4 hours under a nitrogen gas atmosphere to obtain a maleic anhydride adduct (A) having a total acid value of 109. (Regarded as MLB-1.) (2) A 14-necked flask equipped with the same equipment as in item (1) has a number average molecular weight of 1050, a double bond microstructure of 71% cis 1,4 structure, trans 1, 4 structure 26
% and a vinyl structure of 3%, a viscosity of 210 centipoise at 20°C, an iodine value (Wiss method) of 490, 551 g of liquid polybutadiene, 49 g of maleic anhydride, and 2.4 g of iron naphthenate react in the same manner to give a total acid value of 89.0. A body (A) was obtained. (Defined as MLB-2.) (3) Liquid with a number average molecular weight of 600, 31% cis 1,4 structure, 64% trans 1,4 structure, and 5% vinyl structure, viscosity 50 centipoise at 30°C, and iodine value 449. 516g polybutadiene, 84g maleic anhydride
and Antigen PA (trade name, Sumitomo Chemical Co., Ltd.) (180 mg) were reacted in the same manner to obtain the isoadduct (A) with a total oxidation rate of 150. (This is referred to as MLB-3.) Reference Example 2 Production of ring-opening reaction product of maleated liquid polybutadiene (1) Maleated liquid polybutadiene was placed in a 500 mL four-necked flask equipped with a stirrer, a thermometer, a cooling tube, and an inert gas introduction pot. Polybutadiene (MLB-1) 200
g, ethylene glycol monoethyl ether acetate (abbreviated as EGA)97 as a solvent.
g, 26.5 g of 2-hydroxyethyl methacrylate (hereinafter abbreviated as HEMA), 0.1 g of phenothiazine, and 2.7 g of N,N-dimethylbenzylamine (hereinafter abbreviated as DMBA) as a catalyst.
and reacted at 80°C for 2.5 hours. At this time, the total acid value was 33.0, and it was confirmed that the acid anhydride was ring-opened and almost half-esterified. (MLB−
1E. ) (2) Into the same equipment as in (1), add 200 g of maleated liquid polybutadiene (MLB-1) as a solvent.
Prepared 93.5 g of EGA and 18.2 g of N,N-dimethylaminoethanol and heated to 110 g under _N2 gas atmosphere.
The total acid value of the reaction system is reduced by reacting for ℃×2hrs.
345, confirming that it was almost half-esterified. (referred to as MLB-1AE) (3) Maleated liquid polybutadiene (MLB-1AE)
2) 200g, EGA96g as solvent, HEMA21.6
g, as phenothiazine 0.1 g and catalyst
2.2 g of DMBA was charged and reacted at 80°C for 3 hours. The acid value of this reaction solution was 28.0. (MLB-2E
shall be. ) (4) Maleated liquid polybutadiene (MLB-
3) 200g, EGA103g as solvent, and
37.2 g of HEMA, 0.1 g of phenothiazine, and 3.8 g of DMBA as a catalyst were charged, and the reaction was carried out at 80°C for 3 hours, so that the acid value of the reaction system became 43.0. (referred to as MLB-3E) (5) Maleated liquid polybutadiene (MLB-3E)
1) 200g, EGA92g and dimethylamine
An acid value of 34.9 was obtained by reacting 14.9 g at 75° C. for 2 hours under an N ₂ gas atmosphere. It was confirmed from the acid value and infrared spectrum that amide bonds were formed in this product. (referred to as MLB-1AM) (6) Maleated liquid polybutadiene (MLB-1AM)
1) 200g, EGA95.5g as solvent,
HEMA13.3g, n-amyl alcohol 9.0g,
Phenothiazine 0.1g and as catalyst
By reacting 2.7 g of DMBA at 80°C for 3 hours, the acid value of the reaction system became 34.5, confirming that almost half-esterification had occurred. (MLB−1EE
shall be. ) Example 1 Sumie epoxy was placed in a 500 m1 flask equipped with a stirrer, thermometer, cooling tube and inert gas inlet.
ELA-128 (Sumitomo Chemical Co., Ltd., bisphenol A type epoxy resin trade name, epoxy equivalent 184
~194) 118g, succinic acid 11.5g, MLB-IE68.0
g, diethylamine 14.2 g and as solvent
Prepare 64.6g of EGA at 90-100℃ under _N2 gas atmosphere.
The reaction was continued for 3 hours until the acid value of the reaction system became 1 or less. Next, 7.07 g of acrylic acid was added and reacted at the same temperature for 3 hours, resulting in an acid value of 1.0. To this reaction solution, 108 g of a separately prepared semi-blocked tolylene dipolyisocyanate EGA solution was added via a dropping funnel at 90° C. over 30 minutes, and the mixture was stirred while keeping it warm for 3 hours. At this time, free NCO was 0%. 370 g of the electrodeposition resin obtained in this way was
- 6.5 g of butyltin dilaurate, 6.5 g of acetic acid and deionized water were added to obtain an electrodeposition solution with a resin solids content of 15%. The results are shown in Table 1. The semi-blocked tolylene diisocyanate composition described above was prepared as follows. Tolylene diisocyanate (2, 4/2, 6-80/20) (hereinafter
It is abbreviated as TDI. ) 174g and as solvent
Add 130g of EGA and stir under _N2 gas atmosphere at 20~45℃.HEMA130g (phenothiazine)
0.13 g (dissolved)) was added dropwise over 1 hour. The temperature was raised to 60°C 30 minutes after the dropwise addition, and the mixture was stirred while keeping it warm for 1.5 hours. The NCO at this time was 9.6% (di-n-butylamine-hydrochloric acid titration method), confirming the production of semi-blocked isocyanate by HEMA. Example 2 Sumiepoxy ELA-128 118g, malonic acid
13.1g, MLB-2E 80g, diethylamine 16.0g
and 66.1g of EGA as a solvent at 85-90℃.
The acid value was brought to 1 or less by stirring while keeping it warm.
Subsequently, 7.1 g of acrylic acid was charged and the mixture was stirred at the same temperature to bring the acid value to 0.7. Next, HEMA prepared in the same manner as Example 1
108 g of semi-blocked TDI.EGA solvent was reacted at 85 to 90° C. in the same manner as in Example 1 until NCO reached zero. 6.5 g of DBTL, 6.8 g of acetic acid, and deionized water were added to 400 g of the obtained resin to prepare an electrodeposition solution having a resin solid content of 15%. The results are shown in Table 1. Example 3 Sumiepoxy ELA128 73g, Sumiepoxy
ESA 011 (Sumitomo Chemical Co., Ltd., bisphenol A type epoxy resin, epoxy equivalent 450~
500) 45g, fumaric acid 5.0g, diethylamine 15.5
g: 4.3 g of acrylic acid, 80 g of MLB-3E, and 61.2 g of EGA as a solvent were charged and stirred at 85 to 90°C until the acid value of the reaction system became 1 or less. 280g of obtained resin and completely blocked TDI.EGA
A 15% resin solids electrodeposition solution was prepared by mixing 129 g of the solution with 6.3 g of DBTL, 11.2 g of acetic acid, and deionized water. The results are shown in Table 1. The completely blocked TDI.EGA solution described above was prepared in an N ₂ gas atmosphere as follows. A solution of 174 g of TDI and 130 g of EGA, which is the same as shown in Example 1, was heated to 25 to 45°C while stirring, and 130 g of HEMA was added.
(0.13 g of phenothiazine dissolved) was added dropwise over 1 hour, then the temperature was raised to 60°C over 30 minutes, and the mixture was stirred while keeping it warm for 1.5 hours. NCO at this time was 9.6%. Next, cool to 25℃ and N-methyldiethanolamine
Prepare a solution of 59.7g and 25.7g of EGA in about 1 hour while stirring while keeping it warm at below 45℃, and do the same in about 30 minutes.
The temperature was raised to 60°C, and the mixture was stirred for 1.5 hours. Free NCO in this reaction solution was 0. Example 4 Sumiepoxy ESA-011 35.5g, Sumiepoxy ELA-128 83g, acrylic acid 7.2g, cyanoacetic acid 19.0g, MLB-1EE 65g, diethylamine
15.0g and 68.4g of EGA as a solvent at 85-90
The acid value was reduced to 1 or less by reacting at ℃ for 6.5 hours. Next, prepared in the same manner as in Example 1
A urethanized resin was obtained by charging 108 g of HEMA semi-blocked TDI.EGA solution and stirring at 85° C. for 3 hours. 6.6 g of acetic acid and deionized water were added to 370 g of this resin to prepare an electrodeposition solution with a resin solid content of 15%. The results are shown in Table 1. Comparative example 1 Sumiepoxy ELA-128 103g, MLB-1AE
81g, diethylamine 9.3g and as solvent
The acid value was reduced to 0.2 by charging 48.1 g of EGA and stirring at 85 to 90°C for 10 hours. Next, 94 g of the same HEMA semi-blocked TDI.EGA solution used in Example 1 was charged for about 30 minutes with stirring at a temperature below 45°C, and further reacted at 90°C for 3 hours to reduce free NCO to substantially 0. . After cooling the reaction solution, 5.6 g of DBTL, 6.1 g of acetic acid, and deionized water were added to prepare an electrodeposition solution with a resin solid content of 15%. Comparative example 2 Sumiepoxy ESA-011 150g, diethylamine 15.8g, acrylic acid 7.2g, hydroquinone
Prepare 0.5g and 74g of EGA as a solvent,
Acid value 1.4 by stirring at 100℃ for 3.5 hours
I made it. Next, 137 g of the same HEMA semi-blocked TDI.EGA solution used in Example 1 was added dropwise over about 30 minutes while stirring at 80°C, and then heated to 100°C.
The mixture was stirred and kept warm for 3 hours. To this resin were added 8.2 g of DBTL, 7.5 g of acetic acid, and deionized water to prepare an electrodeposition solution with a resin solid content of 15%. The results of Comparative Examples 1 and 2 are shown in Table 1. 【table】

Claims (1)

[Scope of Claims] 1 (a) An alcoholic hydroxyl group selected from an aliphatic alcohol, an amino alcohol having a tertiary amino group, and a hydroxyl group-containing methacrylic ester in the maleated product (A) of liquid polybutadiene having a molecular weight of 500 to 5000. The compound (D) obtained by reacting the compound (B) and/or the secondary monoamines (C) having , saturated and unsaturated aliphatic dicarboxylic acids,
An epoxy modifier (F) selected from aromatic dicarboxylic acids, acrylic acid and cyanoacetic acid and a second
Compounds obtained by reacting with class monoamines (G)
(H) and (B) A resin composition for electrodeposition coatings, which comprises as a main component a completely blocked organic polyisocyanate. 2. The resin composition for electrodeposition paint according to claim 1, wherein a mixture containing compound (H) and a completely blocked organic polyisocyanate as main components is neutralized with an organic carboxylic acid. 3 (a) A maleated liquid polybutadiene having a molecular weight of 500 to 5000 (A), and a compound (B) having an alcoholic hydroxyl group selected from aliphatic alcohols, amino alcohols having a tertiary amino group, and methacrylic acid esters containing a hydroxyl group. and/or a compound (D) obtained by reacting secondary monoamines (C) to perform partial esterification and/or partial amidation, an epoxy compound
(E), a compound obtained by reacting with an epoxy modifier (F) selected from saturated and unsaturated aliphatic dicarboxylic acids, aromatic dicarboxylic acids, acrylic acid and cyanoacetic acid, and secondary monoamines (G) ( H)
and (b) a partially blocked organic polyisocyanate. 4. The resin composition for electrodeposition paint according to claim 3, wherein the reaction product is neutralized with an organic carboxylic acid.