JPH0142303B2 - - Google Patents

Description

[Detailed description of the invention]

The invention disclosed in this application relates to a crosslinking agent component for a baking paint binder having a structure capable of crosslinking by transesterification reaction and/or transamidation reaction, as well as a method for producing the same and its use, particularly a cathodic electrodeposition paint composition. Regarding use inside. European Patent No. BI-0131127 describes transesterification and/or transamidation reactions.
Disclosed is a method for producing a crosslinking component of a binder that can be crosslinked by (amidation). This method uses X-CH ₂ -COOR (where X is -COOR, -
CN, or -COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms), preferably malonic acid and 1 to 4 carbon atoms.
carbonyl compound (preferably formaldehyde,
Particularly preferably paraformaldehyde) is subjected to a reaction to eliminate water by Knoeffenagel reaction format, and the obtained α-disubstituted alkylidene compound is polymerized to form an oligomer or polymer with a molecular weight of 300 to 6000. It is characterized by As a result of research aimed at further improving the properties of coating films obtained using this curing agent component, we found that the reaction (wherein X and R have the above meanings, R ₁
is a hydrogen atom or an alkyl group, and n is a multiple of the above units to have a molecular weight of 300 to 6000). It has been found that in the form of products obtained by partial transamidation with diamines or polyamines, products with improved film-forming ability are obtained. That is, the present invention provides (a1) a compound of formula (), (In the formula, X is -COOR, -CN, or -
COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms,
R ₁ is a hydrogen atom or an alkyl group, n is a multiple of the above unit to have a molecular weight of 300 to 6000), and 0.1 to 1 mole of dihydric and/or polyhydric alkanol.
Partial transesterification reaction with 1.4 hydroxy equivalents,
or (a2) a compound of the formula X—CH ₂ —COOR () (in which ,
or a compound obtained by partial transamidation with at least difunctional primary and/or secondary amines and reacting the obtained precondensate with a carbonyl compound by Knoeffenagel reaction. A paint capable of crosslinking by transesterification, characterized in that (a1) and (a2) have a molecular weight (measured by gel permeation chromatography) of 1000 to 8000. This invention relates to a crosslinking component for a binder. Furthermore, the present invention provides formula (a1) (In the formula, X is -COOR, -CN, or -
COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms,
R ₁ is a hydrogen atom or an alkyl group, and n is a multiple of the above unit to have a molecular weight of 300 to 6000). ( a2) Formula X-CH ₂ -COOR (wherein, X and R
has the same meaning as above) is transesterified with dihydric and/or polyhydric alkanols at 100-200°C, or with at least a difunctional primary alkanol. and/or amidation exchange with a secondary amine, and the resulting uncondensed product is reacted with a carbonyl compound according to the Knoeffenagel reaction format, and polymerized, in either case (a1) or (a2). also crosslinkable for paint binders by transesterification and/or transamidation, characterized in that they yield products with a molecular weight of 1000 to 8000 (determined by gel permeation chromatography). The present invention relates to a method for producing components. Furthermore, the present invention uses the paint binder of the present invention,
The present invention relates to use in combination with a cationic resin having a hydroxyl group and/or a primary and/or secondary amino group in a baking paint composition, especially a paint for electrodeposition coating capable of cathodic deposition. Unlike the binder compositions obtained using the crosslinking component of EP-BI-0131127, the use of the crosslinking component of the present invention has a substantial effect on the properties of the coating compositions prepared therefrom. Can be done. This applies in particular to the properties of the electrodeposition coating, such as the formation of a coating during the crosslinking process, the uniformity of the electrodeposition or the ability to form a complete coating. Furthermore, by carefully selecting the reaction partner compound, the curing properties, adhesion to the coated body, and adhesion to the top coat can be controlled. In particular, according to the present production method, an amide group suitable for cathodic electrodeposition can be introduced into the crosslinking component. A urethane group or urea group can also be introduced by modifying alcohol or amine with an isocyanate compound. Formula () used as starting material in method (a1)
The Knoeffenagel reaction product oligomers are obtained by polymerization of α-disubstituted alkylidene compounds according to EP-BI-0131127. This alkylidene compound is X-CH ₂ -COOR (X is-
It is obtained by the reaction of a compound represented by COOR, --CN, or --COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms, with a carbonyl compound, preferably formaldehyde, with separation of water. The method of the present invention includes malonic acid and malonic acid having 1 to 1 carbon atoms.
Alkanols and diesters of No. 4 (where X is -COOR), such as dimethyl malonate, diethyl malonate, n-propyl malonate, isopropyl malonate, and the like are preferably used. Cyanoacetic acid alkyl esters or cyanoacetic acid cycloalkyl esters such as methyl cyanoacetate, ethyl cyanoacetate, propyl cyanoacetate, butyl cyanoacetate, cyclopentyl cyanoacetate, cyclohexyl cyanoacetate, methyl acetoacetate, and ethyl acetoacetate can also be used. . The carbonyl compound is preferably formaldehyde, particularly its polymer paraformaldehyde. Higher aldehydes can also be used, but offer little advantage over formaldehyde, which is inexpensive and readily available. Ketones such as methyl isobutyl ketone, cyclohexanone can also be used. Oligomers are advantageously produced as follows. Paraformaldehyde is added in portions to the above ester at 60-70°C and dissolved. As a catalyst for this reaction, a mixture of piperidine and formic acid is added in an amount of about 0.1 to 1 mol % based on the ester. While the paraformaldehyde does not dissolve, the reaction temperature is increased to 90°C.
Do not exceed ℃. The temperature is then gradually increased and the water produced in the reaction is entrained off by azeotropic distillation at 120-150° C. using an entrainer, for example an aliphatic or aromatic hydrocarbon. The reaction is monitored by the amount of water produced by the reaction. The simultaneous polymerization is controlled by measuring the refractive index or by measuring the viscosity increase. A peroxide polymerization initiator may be added to complete the polymerization. After removal of the entrainer, the crosslinking agent component can be used substantially without solvent. In order to facilitate handling and improve the distribution of the base resin in the crosslinking agent, an inert solvent may be added as necessary. The molecular weight of the product is about 300 to about 6000
It is. In method (a1), this reaction product is converted into divalent and/or polyvalent alkanol 0.1-1.4OH
equivalent amount (per mole of Knoeffenagel reaction product). To increase the molecular weight, transamidation reactions can also be carried out with at least 0.05 to 1.0 NH equivalents (per mole of product) of difunctional primary and/or secondary amines. These raw materials are selected so that the crosslinking agent component thus obtained has an average molecular weight of 1,000 to 8,000. This molecular weight is gel. It is conveniently measured by permeation chromatography. The reaction of the above products with alkanols or amines is carried out at 130-185°C; the progress of the reaction is monitored by the amount of alcohol separated or by the intrinsic viscosity at 20°C in dimethylformamide. Ru. Suitable for use as dihydric alcohols are linear or branched alkanediols, such as ethylene glycol, its homologues and its isomers. Dialkylene glycol, polyalkylene glycol, polycaprolactone diol, and even 1,1'-isopropylidene-bis(p-phenyleneoxy) diethanol-2
Polyether diols such as cyclic diols such as (DIANOL 22) and tricyclodecane dimethanol (TDC-alcohol DM) can be used similarly. Suitable polyhydric alcohols for use are trimethylolalkane and pentaerythritol. Other suitable diols or polyols can be obtained by simple reactions, for example, the reaction of monoepoxy compounds with secondary alkanolamines or hydroxycarboxylic acids such as dimethylolpropionic acid, or the reaction of diamines with alkylene carbonates. can. Similar reactions to form diols or polyols are known to those skilled in the art. To introduce urethane bonds, reaction products of isocyanate compounds and the alcohols mentioned above can be used as diol or polyol components. In particular, aliphatic primary and secondary amines are used in the transamidation reaction. In addition to these, primary and secondary alkanolamines such as monomethylethanolamine, 2-amino-2-ethylpropanediol, and monoethanolamine, and cyclic polyamines such as hydroxyethylpiperazine and aminoethylpiperazine can also be transamidated. It can be used for. When producing the crosslinking agent component of the present invention by the method (a2), in the first reaction step, _a compound containing an active methylene group, of the formula 5 to 80% of the ester atomic group of the ester represented by
Transesterification or transamidation with diols and/or polyols and/or diamines and/or polyamines at 200°C. When this reaction occurs, alcohol ROH is separated,
Advantageously, this alcohol is removed from the reaction mixture using a bubble column. The progress of this reaction can be monitored by the amount of distillate or the refractive index of the reaction product. The alcohol component used here is the same as that used in method (a1). The amine may be any linear or branched alkylene diamine or polyamine as long as it has primary and/or secondary amino groups. Furthermore, corresponding alkanolamines can also be used in the process of the invention. Such alkanolamines are, for example, ethylenediamine and its homologues, isophoronediamine, diethylenetriamine, and similar substances. The reaction products of amines and isocyanates described above can be used to introduce urea linkages into the crosslinker component. Just as in method (a1), this reaction product is treated in the presence of a catalyst (usually a mixture of piperidine and formic acid or dicyclohexylamine and formic acid).
Carbonyl compounds, more preferably _CH2O from about 90 to
The Knoeffenagel reaction is carried out with formaldehyde in the form of paraformaldehyde containing 100%. Apply a small amount of mixture of ester and catalyst 60~
Advantageously, it is added to paraformaldehyde at 90°C. The reaction temperature should not be higher than 90°C until the paraformaldehyde is completely dissolved. The temperature is then increased to 100° C. and maintained at the same temperature until the free formaldehyde is less than 0.5%. Next, the water produced in the reaction is distilled off using an entraining agent, and the reaction temperature is maintained until the desired viscosity and refractive index are obtained. The reaction occurs when the molecular weight (measured by gel permeation chromatography) of the resulting crosslinker component is approx.
Continue until you reach 1000-8000. It is surprising that the Knoeffenagel reaction also takes place in a trouble-free and controllable manner when using the uncondensed products mentioned above. The crosslinker component produced in accordance with the present invention is used in combination with a base resin capable of transesterification and transamidation. In particular, it is used by mixing it into paint systems that can be diluted with water. It has been found that the present crosslinking component is particularly useful in cathodically depositable coating compositions and, because of its high reactivity, it is possible in many cases to reduce the baking temperature to 130-160°C. Suitable as base resins are resins containing a sufficient number of esterifiable and amidatable groups to ensure sufficient crosslinking of the coating. Resins of this type are disclosed in European Patent No. 0012463 or Australian Patent No. 372099. Preferred resins are epoxy resins, especially those based on epoxy resin amine adducts. These resins may have modified inner flexibilization to make them particularly suitable for cathodic electrodeposition.
Other suitable base resins are copolymers which have been made to contain a sufficient number of protonatable groups by using appropriate monomers or by further modification. The base resin must have an amine number of 20 to 150 mg KOH/g to ensure that sufficient dilution with water is possible when partially or completely neutralized with acid. The number of groups capable of transesterification or transamidation is 40 to 500 mgKOH/g
should be equivalent to In a particular embodiment of the invention, the base resin is partially precondensed with the crosslinker component at 80-140°C. By this method, the compatibility between the two is considerably improved and phase separation can be avoided even when the binder or coating composition is stored for long periods of time. Both components are mixed at a ratio of 60 to 95% by weight of the base resin and 5 to 40% by weight of the crosslinking component of the present invention. A more preferable mixing ratio is 70 to 85% by weight of the base resin and the crosslinking component.
It is 15-30% by weight. A method of processing a binder composition into a water-dilutable coating composition, i.e., neutralizing with acid, diluting to a suitable viscosity for coating, and adding pigments and extenders (extenders). The methods and possible application forms are known to those skilled in the art. A preferred end use for coating compositions containing the crosslinker component of the present invention is cathodic electrodeposition. This coating composition was applied at a temperature of 120 DEG to 180 DEG C. to 15 DEG C. The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.
Parts and percentages in the examples are by weight, unless otherwise specified, and resin components are based on resin solids. In the examples, the following raw material abbreviations are used. ACEE Ethyl acetoacetate MDM Dimethyl malonate MDE Diethyl malonate MDIP Diisopropyl malonate MDBE Di-n-butyl malonate MEBE Ethyl-n-butyl malonate PG 1,2-Propylene glycol NPG Neopentyl glycol BD 1,4-Butanediol HD 1,6-hexanediol TPG Tripropylene glycol CAP Polycaprolactone diol (molecular weight approx. 200) D22 1,1-isopropylidene-bis(p-
(phenyleneoxy) diethanol-2 (dianol 22) TMP Trimethylolpropane CE C ₉ - C ₁₁ Glycidyl ester of t-monocarboxylic acid MEOLA Monoethanolamine DOLA N,N-diethanolamine EHA 2-ethylhexylamine HMDA 1,6-hexamethylene diamine IPDA Isophoronediamine DCHA Dicyclohexylamine DETA Diethylenetriamine DEAPE N,N-diethylpropanediamine-1,3 DEA Diethylamine FA 100% formaldede (used as 91% paraformaldehyde) ECT Ethylene carbonate PCT Propylene carbonate TDI Tolylene diisocyanate (isomer ratio 80) /20) DMPS Dimethylolpropionic acid AMS Formic acid PIP Piperidine C1 Equimolar reaction product between CE and DOLA C2 Reaction product between 1 mol HMDA and 2 mol ECT C3 Reaction product between 1 mol TDI and 2 mol BD C4 1 mol HMDA and PCT2 C5 Equimolar reaction product of CE and DMPS EGL Ethylene glycol monoethyl ether BUGL Ethylene glycol monobutyl ether DEGM Diethylene glycol dimethyl ether PM Propylene glycol monomethyl ether (methoxypropanol) DMF Dimethylformamide INS Isononanoic acid AS Adipic acid THPSA Tetrahydrophthalic anhydride TOFS Tall oil fatty acid HEOX Hydroxyethyl oxazolidine MIBK Methyl isobutyl ketone Examples 1 to 16 A crosslinking component of the type (a1) is prepared from the raw materials listed in Table 1 as follows. The ester component and the catalyst system (for the ester respectively
A mixture of 0.5-1.0 mol % piperidine and formic acid) is heated to 70-80°C and paraformaldehyde is added in portions. An exothermic reaction occurs, but the temperature remains at 90℃ until the paraformaldehyde is completely dissolved.
Keep it so that it does not exceed. Then gradually increase the temperature to 110~
The temperature is raised to 120°C, and the water produced in the reaction is removed using a suitable reagent. After removing the same agent under reduced pressure, the polyol component or amine component is added and the temperature is raised to the point where distillation begins (approximately 140-180°C). The alcohol component is separated using a bubble tower. The resulting reaction product contains 90-96% solids (determined by drying at 120°C for 30 minutes). Examples 17-25 Crosslinking components of type (a2) are produced from the raw materials listed in Table 2 as follows. A mixture of ester and transesterification component or transamidation component is prepared in a suitable reactor equipped with an azeotropic distillation apparatus and a bubble column for separating the alcohol component formed during the partial transesterification or transamidation reaction. Heat to 120℃, then increase the temperature to 180℃
The alcohol liberated from the ester is separated through a bubble tower. The progress of the reaction can be monitored by the amount of distillate, which can be easily controlled by measuring the refractive index of the reaction mixture. After cooling to 60° C., the catalyst mixture and then the paraformaldehyde are added in portions. The reaction is exothermic and the temperature should not be higher than 90°C. After the formaldehyde has completely dissolved, increase the temperature to 100 °C and keep this temperature until the content of free formaldehyde is lower than 0.5%.
The water produced in the reaction is removed using an entrainment phase, such as a hydrocarbon solvent having an appropriate boiling point range. After the entraining agent is distilled off under reduced pressure, the temperature is maintained until a predetermined value is obtained. The reaction product contains more than 90% solids after drying at 120°C for 30 minutes. Use of the crosslinking component produced according to the invention The crosslinking component produced according to the invention is mixed with various base resins under the conditions shown in Table 3. PM by mixing or partially reacting the components
Make a 70% solution. Preparation of test paint Resin solid content of the indicated binder composition 100 each
g, titanium dioxide 29.5g, carbon black
0.5 g, 17 g of aluminum silicate, and 3 g of basic lead silicate. Furthermore, the transesterification reaction catalyst is mixed uniformly with this. Lead octoate is used to give an effective metal content of 0.5% to the resin solid. After dispersing these pigments, the paint is neutralized with formic acid and diluted to 15% solids with deionized water. For mixtures (samples) 2, 8, 20, and 24, choose white pigmentation. That is, 100 g of resin solid, 37 g of titanium dioxide, and 3 g of basic lead silicate are kneaded together, and lead octoate is used as lead.
Mix evenly so that the content is 0.5%. Test for Acetone Resistance The resistance of the coating to acetone is tested by applying a cotton swab soaked in acetone to the colored coating which has been baked at 160° C. for 30 minutes after cathodic electrodeposition. Record the amount of time the acetone-impregnated cotton is left in place until the paint film is scratched with a fingernail. The base resin used is manufactured as follows.
Note that the MEQ value refers to the number of milliequivalents of unreacted epoxy groups and the number of milliequivalents of amine per gram of sample (solid). Base resin A1: 190 g of bisphenol A-epoxy resin (1 epoxy equivalent) and 1425 g of bisphenol A-epoxy resin (3 epoxy equivalent)
g in 597 g of EGL at 100°C. The solution is cooled to 60° C. and 126 g of DOLA is added. temperature
Gradually raise the temperature to 80℃ over 2 hours and add 169g of DEAPA.
Add. The temperature was further raised to 120°C over 2 hours, and after adding 478 g of CE at this temperature, the liquid was maintained at 130°C for 5 hours while stirring. The obtained liquid
Dilute with EGL to bring the concentration of resin solids to 65%.
The amine value of the resulting resin is 91mgKOH/g,
The hydroxyl number is 265 mg KOH/g. Base resin A2: 2g of azobisisobutyronitrile
Dissolve in 40 g of isopropanol while heating. A monomer mixture consisting of 20 g of glycidyl methacrylate, 20 g of hydroxyethyl methacrylate, 20 g of methyl methacrylate, and 40 g of 2-ethylhexyl acrylate (a clear liquid containing 2 g of azobisisobutyronitrile) was added to this clear solution at reflux temperature (84°C). Continuously add over 2 hours. The reaction mixture is stirred for a further 3 hours at reflux temperature. Diisopropanolamine 16g to BUGL20
A homogeneous solution of 100 g in 100 g was quickly added to the reaction mixture at 85°C, and the reaction was stirred for an additional 2 hours at 90°C. The product was diluted with 13 g of EGL at 90°C and then
Dilute with 10 g of acetone at 40°C. The resulting resin has a solid content of 57% and an amine value of 58 mg.
KOH/g, hydroxyl value 250mgKOH/g. Base resin A3: Dissolve 380g of epoxy novolac resin (epoxy equivalent: approx. 190) in 354g of DEGM,
At 80°C, 269 g of THPSA and HEOX semi-ester;
DEA37g, TOFS140g, acid value 3mg
React until it becomes lower than KOH/g. The obtained resin is mixed with 10 mmol of acetic acid (3N) per 100 g of its solid content, and stirred at 65° C. for 3 hours.
The hydroxyl number of the product is 270 mg KOH/g. Base resin A4: 1627 g (3.43
(gram equivalent), TMP3 mol, AS2 mol, INS1
226 g of polyester (acid value 65 mgKOH/g, COOH value 942 g) consisting of mol and THPSA 1 mol
(0.24 COOH gram equivalent) as an 85% PM solution at 110° C. to give an acid value lower than 5 mg KOH/g. After diluting the product to 70% solids with PM,
MEOLA94.5g (0.9g equivalent), DEAPA78g
(1.2 gram equivalents) and 240 g of PM at 60° C. over 2 hours. Then increase the temperature to 90℃
Keep at this temperature for 1 hour. The solids content in the obtained product is adjusted to 70% with PM. Base resin A5: 570 g (3 gram equivalent) of bisphenol-based epoxy resin (epoxy equivalent: approximately 190) and 317 g of PM are heated to 60°C,
116 g (0.9 gram equivalent) of EHA and 163 g (NH-gram equivalent) of polymeric amine (prepared by the method below)
0.15) for 2 hours to give a MEQ value of 2.06. Then add 1330 g (2.1 gram equivalents) of a 75% PM solution of bisphenol A-epoxy resin (epoxy equivalent weight approximately 475). Furthermore, a solution of 189 g (1.8 gram equivalent) of DOLA dissolved in 176 g of PM was heated at 60℃ for 1 hour.
Add and react over time to obtain a MEQ value of 1.57.
A solution of 78 g (1.2 g equivalent) of DEAPA dissolved in 54 g of PM was added over 1 hour and reacted at 60℃.
Set the MEQ value to 1.46. Raise the temperature to 90°C and then to 120°C for 1 hour. After the viscosity (Gardner-Holt: 6 g of resin + 4 g of PM) reaches -J, adjust the solids content to 65% with PM. The product has an amine value of 117 mg KOH/g and a hydroxyl value of 323 mg.
shows. The polymeric amine is 1 mole of DETA, 3.1 mole of 2-ethylhexyl glycidyl ether, and bisphenol A-epoxy resin (epoxy equivalent: approximately 190).
It is obtained by reacting 0.5 mol with 80% PM solution. The product has a viscosity of 60-80s (DIN 53
211, 100 g of resin + 30 g of PM). Base resin A6: The final preparation stage of the modified epoxy amine adduct described as base resin A4 is
% by weight of polypropylene glycol diglycidyl ether at 90°C and reacted at 120°C until all the glycidyl groups have reacted. The product has an amine value of 76 mgKOH/g and a hydroxyl value (primary
OH) 89mgKOH/g. Base resin A7: Bisphenol A-epoxy resin
A mixture of 98.6 g of EHA (0.75 g equivalent), 326 g (0.3 NH - gram equivalent) of the polymerized amine (used in A-5) and 160 g of PM was added into a solution of 570 g (3 gram equivalent) in 173 g PM at 60°C. So 2
The reaction was continued until the MEQ value reached 2.15. Next, 1330 g of a 75% solution of bisphenol A-epoxy resin (epoxy equivalent: 475) in PM.
(2.1 gram equivalents) and 210 g (2 gram equivalents) of DOLA were added within 30 minutes at 60°C. MEQ value
When a value of 1.72 was reached, 138 g of Diketimine (0.5NH-gram equivalent) (below) dissolved in 245 g of PM was added and allowed to react until the MEQ value reached 1.60. The solids content of the product is 70% and its viscosity (Gardner-Holt, 10g resin + 4g PM)
is LM. The amine value is 117 mgKOH/g. Diketimine manufacturing method: DETA103g MIBK200
g at 120°C, and 36 g of water is separated by azeotropic distillation. After removing the solvent under reduced pressure, the reaction product exhibits a refractive index n ²⁰ _D 1.4672.

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Claims (1)

[Claims] 1 Formula (a1) () (In the formula, X is -COOR, -CN, or -
COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms,
_R1 is a hydrogen atom or an alkyl group, and n is a multiple of the above unit to have a molecular weight of 300 to 6000.
or partial transesterification with polyhydric alkanols from 0.1 to 1.4 hydroxy equivalents, or from 0.05 to at least difunctional primary and/or secondary amines.
A compound obtained by partial transamidation reaction with 1.0NH equivalent, or ( _a2 ) of a compound of formula () Partial transesterification of ester groups with dihydric and/or polyhydric alkanols up to 5 to 80% or partial transamidation with at least difunctional primary and/or secondary amines, resulting in an uncondensed product is obtained by reacting with a carbonyl compound by the Knoeffenagel reaction, and the molecular weight of the compounds (a1) and (a2) (measured by gel permeation chromatography) is 1000. A crosslinking component for a paint binder that can be crosslinked by transesterification and/or transamidation reaction, characterized in that it has a molecular weight of 8000 to 8000. 2 In the compounds of formulas () and (), X
The crosslinking component according to claim 1, wherein is a -COOR group and R is an alkyl group having 1 to 4 carbon atoms. 3. The crosslinking component according to claim 1 or 2, in which formaldehyde or paraformaldehyde is used as a carbonyl compound in the Knoeffenagel reaction. 4. The crosslinking component according to any one of claims 1 to 3, which contains a urethane bond and/or a urea bond in its structure. 5 (a1) Formula () (In the formula, X is -COOR, -CN, or -
COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms,
_R1 is a hydrogen atom or an alkyl group, and n is a multiple of the above unit to have a molecular weight of 300 to 6000). and/or transesterified with polyhydric alkanols at 130-185°C or transamidated with 0.05-1.0NH equivalents of at least difunctional primary and/or secondary amines, (a2) of formula () X—CH ₂ —COOR () (wherein, X and R have the same meanings as above)
100-200 with dihydric and/or polyhydric alkanols
℃, or transamidation with at least difunctional primary and/or secondary amines, and the resulting uncondensed product is reacted with a carbonyl compound in the Knovenagel reaction format, resulting in polymerization. A transesterification reaction characterized in that a product having a molecular weight of 1000 to 8000 (measured by gel permeation chromatography) is obtained in both cases of (a1) and (a2) by Alternatively, a method for producing a crosslinking component for a paint binder that can be crosslinked by transamidation reaction. 6 Claims in which malonic acid, an alkanol having 1 _to 4 carbon atoms, and a diester are used as a compound having the structure of The method described in Section 5. 7. The method according to claim 5 or 6, in which formaldehyde or paraformaldehyde is used as a carbonyl compound in the Knoeffenagel reaction. 8 (a1) Formula () (In the formula, X is -COOR, -CN, or -
COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms,
_R1 is a hydrogen atom or an alkyl group, and n is a multiple of the above unit to have a molecular weight of 300 to 6000.
or partial transesterification with polyhydric alkanols from 0.1 to 1.4 hydroxy equivalents, or from 0.05 to at least difunctional primary and/or secondary amines.
A compound obtained by partial transamidation reaction with 1.0NH equivalent, or ( _a2 ) of a compound of formula () Partial transesterification of ester groups with dihydric and/or polyhydric alkanols up to 5 to 80% or partial transamidation with at least difunctional primary and/or secondary amines, resulting in an uncondensed product. is obtained by reacting with a carbonyl compound by the Knoeffenagel reaction, and the molecular weight of the compounds (a1) and (a2) (measured by gel permeation chromatography) is 1000. ~ 8000, containing any of the crosslinking components for paint binders that can be crosslinked by transesterification and/or transamidation reaction, containing hydroxyl groups and/or primary and/or secondary amino groups This method is used in combination with a cationic resin. 9 (a1) Formula () (In the formula, X is -COOR, -CN, or -
COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms,
_R1 is a hydrogen atom or an alkyl group, and n is a multiple of the above unit to have a molecular weight of 300 to 6000.
or partial transesterification with polyhydric alkanols from 0.1 to 1.4 hydroxy equivalents, or from 0.05 to at least difunctional primary and/or secondary amines.
A compound obtained by partial transamidation reaction with 1.0NH equivalent, or ( _a2 ) of a compound of formula () Partial transesterification of ester groups with dihydric and/or polyhydric alkanols up to 5 to 80% or partial transamidation with at least difunctional primary and/or secondary amines, resulting in an uncondensed product The molecular weight of the compounds (a1) and (a2) (measured by gel permeation chromatography) is from 1000 to 1000. 8000, in which any crosslinking component for a paint binder capable of being crosslinked by transesterification and/or transamidation reaction is used in a partially precondensed form with a cationic resin. 10 Resin having hydroxyl group and/or primary and/or secondary amino group and (a1) formula () (In the formula, X is -COOR, -CN, or -
COCH ₃ , R is an alkyl group having 1 to 8 carbon atoms,
_R1 is a hydrogen atom or an alkyl group, and n is a multiple of the above unit to have a molecular weight of 300 to 6000.
or partial transesterification with polyhydric alkanols from 0.1 to 1.4 hydroxy equivalents, or from 0.05 to at least difunctional primary and/or secondary amines.
A compound obtained by partial transamidation reaction with 1.0NH equivalent, or ( _a2 ) of a compound of formula () Partial transesterification of ester groups with dihydric and/or polyhydric alkanols up to 5 to 80% or partial transamidation with at least difunctional primary and/or secondary amines, resulting in an uncondensed product The molecular weight of the compounds (a1) and (a2) (measured by gel permeation chromatography) is from 1000 to 1000. 8000, and which contains as a binder a mixture or partial condensate of a crosslinking component for a paint binder that can be crosslinked by transesterification and/or transamidation reaction. .