JPH03294498A - Formation of coating film - Google Patents

Abstract

PURPOSE:To form a coating film excellent in rust resistance, smoothness, edge coverage, etc., by coating a material with a cationic electrodeposition paint consisting of a resin contg. a hydroxyl group and a cationic group and a specified epoxy resin, washing the coat with water, treating the uncured coat with an aq. cationic soln. and baking the coat. CONSTITUTION:A material is coated in a cationic electrodeposition paint I contg. a resin A (e.g. a reaction product of an epoxy resin and a cationizing agent) and an epoxy resin B having >=2 epoxy group-contg. functional groups as a combination of an alicyclic skeleton and/or an org. alicyclic skeleton with an epoxy group on average per molecule as the essential resin components to form a coating film having about 10-70mum thickness. The coated material is then washed with water, the uncured film is treated in an aq. cationic soln. II contg. the resin A and epoxy resin B as the essential resin components, and the treated coat is baked and cured to form an electrodeposition coating film having about 1-4mum thickness.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a method for forming a coating film, and more specifically, the present invention relates to a method for forming a coating film, and more specifically, the present invention relates to a method for forming a coating film. Excellent performance in terms of coating film adhesion, weather resistance, corrosion resistance, and low-temperature curing properties.
Furthermore, the present invention relates to a coating film forming method with improved coverage of sharp corners (edges) of a coated object (edge coverage).

[Prior art and its problems] Conventionally, as a resin composition for cationic electrodeposition coatings, aromatic polyisocyanate compounds blocked with polyamine resins such as amine-added epoxy resins and alcohols, etc.
Curing agents) are the most commonly used, and have received excellent reviews regarding the anticorrosion properties of coatings. However, an essential problem with this resin composition for coatings is that the curing initiation temperature is high (170°C or higher); may poison the firing furnace exhaust combustion catalyst; furthermore, when heated at high temperatures to harden the coating, the block polyisocyanate thermally decomposes, producing tar and soot, and yellowing the top coat. It has serious drawbacks such as causing bleeding, curing inhibition, etc., as well as significantly lowering the weather resistance of the top coat and being susceptible to whitening, and there has been a strong desire for improvement.

For this reason, the present applicant has developed a cationic electrolyte that has the excellent advantages of the incyanate curing type without using block polyisocyanate compounds or organic tin compounds, and eliminates the above-mentioned disadvantages caused by using these compounds. As a resin composition for a paint coating, a resin (A) containing a hydroxyl group and a cationic group; and an epoxy group-containing functional group formed by bonding an epoxy group to an alicyclic skeleton and/or a bridged alicyclic skeleton; Epoxy resin with an average of 2 or more molecules per molecule (
We have proposed a resin composition for cationic electrodeposition coatings, which is characterized by containing B) as a main component.

The composition can be cured at a low temperature of 160° C. or lower without using a tin catalyst; furthermore, since it does not use a blocked isocyanate compound or its derivative, it does not suffer from the various defects described above due to its use. Can eliminate: No volume shrinkage due to thermal decomposition and good adhesion; Since aromatic urethane bonds or aromatic urea bonds are not introduced during cross-linking, weather resistance is less likely to be impaired; Electrodeposition coating film Excellent corrosion resistance and hardening properties:
It has various excellent advantages such as good stability of the electrodeposition bath.

However, as a result of further research by the present inventors, it was found that the above composition had insufficient edge covering performance.

Therefore, the present inventors conducted intensive research with the aim of improving the edge coverage without impairing the advantages of the above compositions, and as a result, the above resin (A) and epoxy resin (B)
It is electrodeposited in a cationic electrodeposition paint containing as the main resin component, and then after washing with water, it is coated with a cationic aqueous liquid containing resin (A) and epoxy resin (B) as the main resin components while remaining uncured. The present invention was completed based on the discovery that the object can be achieved through processing.

Thus, according to the present invention, one molecule contains an epoxy group-containing functional group formed by bonding the resin (A) containing a hydroxyl group and a cationic group and an epoxy group to an alicyclic skeleton and/or a bridged alicyclic skeleton. Electrodeposition coating is carried out in a cationic electrodeposition paint (I) containing as a main resin component an epoxy resin (B) having an average of 2 or more per epoxy resin, and then the simple removal coating is washed with water, and then uncured as described above. Resin (A) and the above epoxy resin (
A cationic aqueous liquid (1) containing B) as the main component.
A method of forming a coating is provided which is characterized by visual treatment followed by baking.

The resin composition for cationic electrodeposition paint used in the present invention (hereinafter sometimes abbreviated as "the present composition") comprises the above-mentioned (A)
This is a composition whose main components are Component (B) and Component (B).

Electrodeposited coatings formed using the present compositions cure and persist at temperatures below about 250°C. and especially lead, zirconium,
When one or more compounds containing metals such as cobalt, aluminum, manganese, copper, zinc, iron, chromium, and nickel are blended as a catalyst, curing can be achieved even by heating at a low temperature of about 0°C to about 160°C. In these curing, the epoxy group contained in the epoxy resin (B) opens the ring and reacts with the hydroxyl group (preferably primary type) in the resin (A), and then It is presumed that the epoxy groups react with each other to form ether bonds, resulting in crosslinking and curing.

Components (A) and (B), which are the main components of the present composition, will be explained in more detail below.

Any resin that contains a hydroxyl group that reacts with the epoxy group of component (B) and has a sufficient number of cationic groups in the same molecule to form a stable aqueous dispersion is included. Ru. Examples of component (A) include the following.

(ii) A reaction product obtained by reacting a polyepoxy resin with a cationizing agent; (II) A polycondensate of a polycarboxylic acid and a polyamine (see also U.S. Pat. No. 2,450,940). (I) Polyadducts of polyisocyanates and polyols with mono- or polyamines are protonated with acids: (1v) Copolymers of acrylic or vinyl monomers containing hydroxyl groups and amino groups are protonated with acids. protonated with (
Special Publication No. 45-12395, Special Publication No. 45-1239
(V) An adduct of a polycarboxylic acid resin and an alkylene imine which is protonated with an acid (see US Pat. No. 3.403.
088 specification); etc.

For specific examples and manufacturing methods of these cationic resins, see, for example, Japanese Patent Publication No. 45-12395,
-12396 Publication, Special Publication No. 49-23087,
U.S. Patent No. 2.450.940, U.S. Patent No. 3
．． No. 403.088, U.S. Patent No. 3.891,5
No. 29, US Pat. No. 3,963,663, etc., and therefore these citations will be used here instead of a detailed description.

Particularly desirable as component (A) in the present invention is a polyepoxide compound obtained by reacting a cationizing agent with the epoxy group of a polyepoxide compound with excellent corrosion resistance obtained from a polyphenol compound and epichlorohydrin, which is included in the above (1). It is a reactive product.

The polyepoxide compound is an epoxy group compound, generally having a molecular weight of at least 200, preferably between 400 and 4,000.
More preferably, those having a number average molecular weight within the range of 800 to 2.000 are suitable. As such polyepoxide compounds, those known per se can be used, and include, for example, polyglycidyl ethers of polyphenol compounds that can be produced by reacting polyphenol compounds with epichlorohydrin in the presence of an alkali. . Examples of the polyphenol compounds used here include bis(4-hydroxyphenyl)-2,2-propane, 4,4'-dihydroxybenzophenone, and bis(4-hydroxyphenyl)-2,2-propane.
-1,1-ethane, bis(4-hydroxyphenyl)-
1,1-isobutane, bis(4-hydroxy-tert
-butyl-phenyl)-2,2-propane, bis(2-
hydroxynaphthyl) methane.

1.5-dihydroxynaphthalene, bis(2,4-dihydroxyphenyl)methane, tetra(4-hydroxyphenyl)-1,1,2,2-ethane, 4.4'-dihydroxydiphenyl ether, 4.4'-dihydroxy Examples include diphenyl sulfone, phenol novolac, talesol novolac, and the like.

Among the above-mentioned polyepoxide compounds, those particularly suitable for the preparation of component (A) have a number average molecular weight of at least about 3.
80, more preferably about 800 to about 2.000, and an epoxy equivalent weight of 190 to 2.000, preferably 400 to 1,
It is a polyglycidyl ether of a polyphenol compound within the range of 000, especially one represented by the following formula %07). The polyepoxide compound may be partially reacted with a polyol, polyether polyol, polyester polyol, polyamide amine, polycarboxylic acid, polyisocyanate, etc., and further,
Graft polymerization of δ-4 caprolactone, acrylic monomer, etc. may be performed.

On the other hand, examples of the cationizing agent for introducing a cationic group into the polyepoxide compound include aliphatic, alicyclic, or aromatic-aliphatic primary or secondary amines, tertiary amine salts, secondary Examples include sulfide salts and tertiary phosphine salts. These react with epoxy groups to form cationic groups. Furthermore, a tertiary amino monoisocyanate obtained by the reaction of a tertiary amino alcohol and a diisocyanate can be reacted with a hydroxyl group of an epoxy resin to form a cationic group.

Examples of the amine compound in the cationizing agent include:
For example, the following can be exemplified.

(1) Methylamine, ethylamine, n- or 1so-
Propylamine, monoethanolamine, n- or 1s
Primary amines such as o-propaturamine: (2) Secondary amines such as diethylamine, jetanolamine, di-n- or lso-propaturamine, N-methylethanolamine, N-ethylethanolamine: ( 3) Polyamines such as ethylenediamine, diethylenetriamine, hydroxyethylaminoethylamine, ethylaminoethylamine, methylaminopropylamine, dimethylaminoethylamine, dimethylaminopropylamine.

Among these, alkanolamines having a hydroxyl group are preferred, and the primary amino group may be reacted with a ketone in advance to block it, and then reacted with the epoxy group using the remaining active hydrogen.

Furthermore, in addition to the above-mentioned amine compounds, basic compounds such as ammonia, hydroxylamine, hydrazine, hydroxyethylhydrazine, and N-hydroxyethylimidacillin compounds can also be used. The basic group formed using these compounds can be protonated to a cationic group with an acid, particularly preferably a water-soluble organic carboxylic acid such as formic acid, acetic acid, glycol or lactic acid.

Furthermore, triethylamine, triethanolamine, N
, N-dimethylethanolamine, N-methyljetanolamine, N,N-diethylethanolamine, N-
Tertiary amines such as ethyljetanolamine can also be used, and these can be preprotonated with acid and reacted with epoxy groups to form quaternary salts.

In addition to amino compounds, salts of sulfides such as diethyl sulfide, diphenyl sulfide, tetramethylene sulfide, and thiogetanol with boric acid, carbonic acid, organic monocarboxylic acids, etc. can be reacted with epoxy groups to form a tertiary compound.
It may also be used as a class sulfonium salt.

Furthermore, a salt of a phosphine such as triethylphosphine, phenyldimethylphosphine, diphenylmethylphosphine, or triphenylphosphine and the above-mentioned acid may be reacted with an epoxy group to form a quaternary phosphonium salt.

Examples of the hydroxyl group of component (A) used in the present invention include:
The alkanolamine in the above cationizing agent, the ring-opened product of caprolactone that may be introduced into the epoxide compound, the primary hydroxyl group that can be introduced from polyol, etc.:
Secondary hydroxyl groups in epoxy resins: Among these, primary hydroxyl groups introduced by alkanolamines are preferred because they have excellent crosslinking and curing reactivity with component (B).Such alkanolamines are The cationizing agents listed above are preferred.

The content of hydroxyl groups in component (A) is 20 to 5,000 in terms of hydroxyl equivalent, particularly 100 to 1.000, in terms of crosslinking and curing reactivity with the epoxy group contained in component (B).
It is preferable that the primary hydroxyl equivalent is within the range of 200 to 200.
The content of the cationic group is preferably within the range of 1.000, and the content of the cationic group is preferably at least the minimum necessary to stably disperse the component (A), Generally 3 to 200, especially 10 in terms of amine value),
It is also possible to use aqueous dispersion using a surfactant etc., but in this case, the pH of the aqueous dispersion composition
It is desirable to adjust the cationic group so that the number is usually 4 to 9, more preferably 6 to 7.

Component (A) used in the present invention has a hydroxyl group and a cationic group, and preferably does not contain free epoxy groups in principle.

A curing agent for forming a crosslinked cured coating film mainly through the etherification reaction with the above (A) component as described above, which contains a specific "epoxy group-containing functional group" on average per molecule. It has two or more, preferably three or more.

That is, the epoxy group-containing functional group in component (B) consists of an alicyclic skeleton and/or a bridged alicyclic skeleton and an epoxy group, and the alicyclic skeleton has 4 to 10 members, preferably 5 to 10 members. The bridged alicyclic skeleton contains a condensed ring in which two or more 6-membered saturated carbocyclic rings or chain rings are condensed, and the bridged alicyclic skeleton contains a ring between two carbon atoms constituting the above cyclic or polycyclic ring. linear or branched C3-6 (preferably 01-4)
Alkylene group [e.g. -CH, -CH-CH* -
1-CH(CH,)--CH2(CH,)cHx-1C
(CHs)2--CH(C,H,)CH,-, etc.] contains a ring bonded with a bridge (endomethylene, endoethylene, etc.).

One of the carbon atoms in the poxy group is directly bonded to a ring carbon atom in the alicyclic skeleton or bridged alicyclic skeleton [for example, see formulas (I) and (II) 1 below, or Two carbon atoms of the epoxy group and two adjacent carbon atoms constituting the ring in the alicyclic skeleton or bridged alicyclic skeleton are common [for example, the following formula (Ill), (IV ) is important.

Specific examples of such epoxy group-containing functional groups include those represented by the following formulas (1) to (1v).

Km In the formula, R,, R,, R1, R5, R6, R1, R1° and R1+ each represent H, CH3 or CH,
And R4, R6 and R9 each represent H or CH.

Component (B) may have an average of at least 2, preferably 2 or more, more preferably 4 or more epoxy group-containing functional groups per molecule selected from the above formulas (I) to (IV), such as At least one epoxy group-containing functional group represented by formula (I) or (II) can be polarized, or at least one epoxy group-containing functional group represented by formula (III) or (+V) can be polarized. . Furthermore, the epoxy resin (B) contains at least one epoxy group-containing functional group represented by formula (I) or (II) and an epoxy group-containing functional group represented by formula (Ill) or (1■). It is also possible to have at least one type in the same molecule or in different molecules.

Among the above, epoxy group-containing groups represented by the formulas (1) and (Ill) are preferred, and in particular, epoxy group-containing functional groups represented by the following formula (V) and the following formula (1) and (B) component The epoxy equivalent and molecular weight of are not strictly limited and can be changed depending on the manufacturing method and the use of the final resin composition. 2,000, preferably 150-500, more preferably 150-25
0, and the number average molecular weight is usually 400 to 100,000, preferably 700 to 50,000.
00, more preferably within the range of 700 to 30.000.

Component (B) having two or more such epoxy group-containing functional groups in one molecule is disclosed in, for example, Japanese Patent Publication No. 56-8016, Japanese Patent Application Laid-open No. 57-47365, and Japanese Patent Application Laid-open No. 60-1.
No. 66675, Japanese Patent Application Laid-open No. 63-221121,
It is described in documents such as Japanese Unexamined Patent Publication No. 63-234028, and any known one can be used.

Alternatively, (B) having the above epoxy group-containing functional group
The components are obtained by methods known per se, and the main manufacturing methods are listed below, but are not limited to these.

First production method = partial epoxidation of a part of the double bonds of the alicyclic compound (X) having two or more carbon-carbon double bonds in one molecule, and ring-opening polymerization of the epoxy groups; A method of epoxidizing the double bonds remaining in the polymer.

Second production method: A method in which an alicyclic compound (Y) having two or more epoxy groups in the same molecule is subjected to ring-opening polymerization based on the epoxy groups to such an extent that all of the epoxy groups are not eliminated.

Third production method: A method of polymerizing a compound (Z) having an epoxy group-containing functional group and a polymerizable unsaturated bond in the same molecule.

Hereinafter, these manufacturing methods will be explained in more detail.

Part of the double bonds contained in an alicyclic compound having two or more carbon-carbon double bonds in one molecule (hereinafter abbreviated as "alicyclic compound (X)") (partially epoxidized product C), and then ring-opening polymerization of the epoxy groups to obtain a ring-opening polymer of the partially epoxidized product, and then a part or all of the double bonds remaining in the polymer are epoxidized. Component (B) is obtained by

The alicyclic compound (X) has a basic skeleton of the alicyclic ring or bridged alicyclic ring structure described above for the alicyclic skeleton or bridged alicyclic skeleton, and further includes a double bond and an adjacent alicyclic ring structure constituting the ring. It is a compound that exists between two carbon atoms, or contains at least two or more double bonds based on other carbon atoms that are directly bonded to the carbon atoms constituting the ring structure.

The alicyclic compound (X) can also be obtained, for example, by heating a conjugated diene compound according to a known method. Conjugated diene compounds contain one double bond in a conjugated relationship in one molecule.
Suitable are aliphatic or alicyclic compounds having 4 to 30 carbon atoms, preferably 1 to 5 pairs, such as butadiene, isoprene, birylene, 1,3-hexadiene, 2. 4-hexadiene, 2,4-peptadiene, 2-methyl-6-methylene-2,7-octadiene,
2.6-dimethyl-1.5.7-octatriene, cyclopentadiene, cyclohexadiene, 4-ethyl-2
-Methylcyclopentadiene, 3-isopropyl-1-
Methylcyclopencdiene, 5-isopropylcyclopencdiene, 1.2.3.4-tetraphenylcyclopentadiene, 1.2.4-1-diphenylcyclopencdiene, 1.4-diphenylcyclopencdiene, 1.
3-octachlorpentadiene, hexachlorcyclopentadiene, 5.5-jethoxy-1,2゜3.4-tetrachlorocyclopentadiene, 1.2.3.4.5-
Pentachlorcyclopentadiene, 1.2.3.4-tetrachlorocyclopentadiene, 1.3-cyclopentadiene, 1.3-cyclooctanediene, l, 3.5-
Examples include cyclooctatriene, 1.3.6-cyclooctatriene, cyclooctatetraene, chlorocyclooctatetraene, bromocyclooctatetraene, 5-cyclohexylidenecyclopentadiene, and each of these can be used alone. Alternatively, two or more types can be used in combination.

When the conjugated diene compound is reacted under heating using a Ziegler catalyst if necessary, an alicyclic compound (X) is obtained. This heating reaction can be carried out by a method known per se, for example, by the method disclosed in JP-A-49-102643. Representative examples of the alicyclic compound (X) obtained in this manner are as follows.

Among the above conjugated diene compounds, compounds having an alicyclic structure such as cyclopentadiene, cyclohexane diene, 4-ethyl-2-methylcyclopentadiene, sylvestrene, 2.8 (9)-p-menthadene, vilonene, etc. , 1,3-dimethyl-1-ethyl-3,5-cyclohexadiene, terpinene, phelandrene, dipentene, isolimonene, limonene, etc. are already known as alicyclic compounds (
Since it has the structure X), it can be used as it is without being subjected to the above thermal reaction.

First, a part of the carbon-carbon double bonds contained in the alicyclic compound (X) is modified into an epoxy group using a peroxide or the like (
Partial epoxidation) A partially epoxidized product is one in which a part of the plurality of double bonds contained in the alicyclic compound (X) is modified into an epoxy group, and specific examples thereof are as follows. It can be used as a oxidant.

Partially evo-partially epoxidized products such as naturally-obtained epoxycarene have at least one epoxy group and at least one carbon-carbon double bond in one molecule, and the double bond is connected to an adjacent ring constituting the ring. It is necessary that a double bond exists between two carbon atoms or is attached to a carbon atom of a chain ring based on another carbon atom.

Next, ring-opening polymerization is performed based on the epoxy groups in this partially epoxidized product to obtain a polymer of the alicyclic compound (X). It is preferable to use an initiator for this ring-opening polymerization, and a residue X derived from the initiator component may be bonded to the terminal of component (B), which is the final product. Examples of organic compounds having active hydrogen, which is an organic compound residue and a precursor thereof, include alcohols, phenols, carboxylic acids, amines, and thiols. Among these, the alcohol may be either a monohydric alcohol or a polyhydric alcohol of dihydric or higher hydrity, and specifically, for example, methanol, ethanol, propatool, butanol, pentanol, hexanol, octatool. Aliphatic monohydric alcohols such as benzyl alcohol; aromatic monohydric alcohols such as benzyl alcohol: ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol,
Dipropylene glycol, 1,3-butanediol, 1
．． 4-butanediol, bentanediol, 1,6-hexanediol, neopentyl glycol, oxypivalic acid neopentyl glycol ester, cyclohexane dimetatool, glycerin, diglycerin, polyglycerin, trimethylolpropane, trimethylolethane, pentaerythritol , polyhydric alcohols such as dipentaerythritol, and the like.

Examples of phenols include phenol, cresol, catechol, progallol, hydroquinone, hydroquinone methyl ether, bisphenol A, bisphenol F, 4,4'-dihydroxybenzophenone, bisphenol S, phenol resin, cresol novolak resin, and the like. It will be done.

Carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, fatty acids from animal and vegetable oils; fumaric acid, maleic acid, adipic acid, dodecanoic acid, trimellitic acid, pyromellitic acid, polyacrylic acid, phthalic acid, isophthalic acid, Examples include terephthalic acid, and compounds having both a hydroxyl group and a carboxylic acid such as lactic acid, citric acid, and oxycaproic acid can also be used.

Furthermore, other active hydrogen-containing compounds include mixtures of alkoxysilanes such as tetramethylsilicate, tetraethylsilicate, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, and phenyltrimethoxysilane with water, or silanol compounds thereof; Polyvinyl alcohol, polyvinyl acetate partial hydrolyzate, starch, cellulose, cellulose acetate, cellulose acetate butyrate, hydroxyethyl cellulose, acrylic polyol resin, styrene
Allyl alcohol copolymer resin, styrene-maleic acid copolymer resin, alkyd resin, polyester polyol resin, polycaprolactone polyol resin, etc. can also be used. In addition, it may have an unsaturated double bond together with active hydrogen, and the unsaturated double bond may be epoxidized. The agents may be the same.

Usually, the above-mentioned organic compound having active hydrogen is used as an initiator,
The above partially epoxidized products, such as 4-vinylcyclohexene-1-oxyto, 4-vinylcyclo[2,2,1]
3-Methyl-4 (or 5)-t-propenyl-1-cyclohexene oxide, 2,4- or 1,4-dimethyl-4ethynyl-1-cyclohexene oxide, 4-vinylcyclo[2,2,1]hebutene Ring-opening polymerization is carried out using -1-oxide (vinylnorbornene oxide), 2-methyl-4-isopropanyl-cyclohexene oxide, etc. singly or in combination. At this time, it is also possible to co-exist other epoxy compounds that do not belong to the above-mentioned partially epoxidized products and carry out ring-opening copolymerization. Any other epoxy compound that can be copolymerized may be used as long as it has an epoxy group, but preferred examples include ethylene oxide, propylene oxide, butylene oxide,
Oxides of unsaturated compounds such as styrene oxide: Glycidyl ether compounds such as allyl glycidyl ether, 2-ethyl, hexyl glycidyl ether, methyl glycidyl ether, butyl glycidyl ether, and phenyl glycidyl ether Unsaturated organic compounds such as nialic acid and methacrylic acid Carboxylic acid glycidyl ester compound: 3
．． Examples include alicyclic oxirane group-containing vinyl monomers such as 4-epoxycyclohexylmethyl (meth)acrylate.

The above-mentioned ring-opening polymer is obtained by ring-opening polymerization (ether bonding) of the epoxy groups contained in the partially epoxidized product alone or in the presence of other epoxy compounds as necessary. The composition ratio of other epoxy compounds in the ring-opening polymer can be arbitrarily selected depending on the purpose, but specifically, the ring-opening copolymer 1 obtained
An average of 2 or more of any one or more of the above structural formulas (I) to (TV) per molecule, preferably an average of 3 or more,
More preferably, it is desirable to select within the range of 4 or more.

The number average molecular weight of the (co)polymer thus obtained is generally 400 to 100,000, particularly 700 to 50.
,000, more preferably within the range of 700 to 30,000.

The ring-opening polymerization reaction is generally preferably carried out in the presence of a catalyst, and examples of the catalyst used include amines such as methylamine, ethylamine, propylamine, and piperazine; organic bases such as pyridines and imidazoles; Types: Organic acids such as formic acid, acetic acid, and propionic acid; Inorganic acids such as sulfuric acid and hydrochloric acid; Alkali metal alcoholades such as sodium methylate; Alkalies such as KOH and NaOH: BF
,, Z n Cl2w1,1ci2. , S n C12
Lewis acids such as No. 4 or complexes thereof, organometallic compounds such as nitriethylaluminum, aluminum acetylacetonate, titanium acetylacetonate, and diethylzinc.

These catalysts are generally used in an amount of 0.001 to 10% by weight, preferably 0.1 to 5% by weight based on the reactants.
It can be used within the range of The ring-opening polymerization reaction temperature is generally about -70 to about 200°C, preferably about -30°C to
It is within a range of about 100°C. The reaction can be carried out using a solvent, and it is preferable to use a conventional organic solvent that does not contain active hydrogen.

The ring-opening polymer contains a double bond based on the alicyclic compound (X), and component (B) can be obtained by epoxidizing all or part of the double bond. Epoxidation of double bonds can be carried out using, for example, epoxidizing agents such as peracids and hydroperoxides. Whether or not a solvent is used during the epoxidation reaction and the reaction temperature can be adjusted as appropriate depending on the equipment used and the physical properties of the raw materials. Depending on the conditions of the epoxidation reaction, a side reaction may occur simultaneously with the epoxidation of the double bond in the raw ring-opening polymer, and a modified substituent may be included in the skeleton of component (B). Examples of this modified substituent include, for example, when peracetic acid is used as an epoxidizing agent, the substituent has the following structure, and this is thought to be due to the reaction between the generated epoxy group and the by-produced acetic acid. .

The epoxy equivalent of component (B) thus obtained is generally in the range of 100 to 2,000, particularly 150 to 500, more preferably 150 to 250.

Commercially available products can also be used as such component (B), such as EHPE-3150, EHPE3100, EH
Examples include PE-1150 [part name manufactured by Daicel Chemical Industries, Ltd.], which is an epoxy resin having a cyclohexane skeleton using 4-vinylcyclohexene-1-oxide and having the following structural formula.

The ratio of these modified substituents included is determined by the type of epoxidizing agent, the molar ratio of the epoxidizing agent to the unsaturated group, and the reaction conditions.

In the formula, n is 2 or more, preferably 3 or more, more preferably 4 or more.

For example, at least two of the double bonds contained in the alicyclic compound (X) are epoxidized, and then ring-opening polymerization is performed so that the epoxy group remains. .

As the alicyclic compound (Y) having an average of two or more epoxy groups per molecule, the following monocyclic or condensed ring compounds are representative.

Specifically, 11 or more of the above epoxidized products are subjected to a ring-opening polymerization reaction in the same manner as described in the first production method, using an initiator and a catalyst as necessary, so that epoxy groups remain. By stopping the reaction at a predetermined reaction point (
B) Obtain the ingredients. Any means such as dilution with a solvent or cooling can be used to stop the reaction. In this manufacturing method as well, the other epoxy compound may be copolymerized in the same manner as in the first manufacturing method.

The component (B) obtained in this way is represented by the formula (I) or (
At least one of the epoxy group-containing functional groups represented by II)
It can also be an epoxy resin having the species and at least one epoxy group-containing functional group represented by the formula (III) or (IV) in the same molecule or in different molecules.

The ring-opened polymer (B) component thus obtained generally has a number average molecular weight of 400 to 100,000, particularly 700 to 100,000.
50.000, and the epoxy equivalent generally ranges from 100 to 2.000, particularly from 150 to 2.000.
500, preferably in the range 150-250.

No. 1! 4W L Yutajido - Compounds (Z) having a small number of epoxy group-containing functional groups and a small number of polymerizable unsaturated bonds (one each) in the molecule include, for example, those shown in the following general formulas can be mentioned.

Examples of divalent aliphatic hydrocarbon groups having 1 to 6 carbon atoms include linear or branched alkylene groups, such as methylene, ethylene, propylene, tetramethylene, ethylethylene, pentamethylene, and hexamethylene groups. etc. can be mentioned. Also.

Examples of the divalent hydrocarbon group having 1 to 10 carbon atoms represented by R1 include methylene, ethylene, propylene, tetramethylene, ethylethylene, pentamethylene, hexamethylene, and porin. In the above general formula, R11 is a hydrogen atom or Represents a methyl group, and R1 is 2 having 1 to 6 carbon atoms.
represents a valent aliphatic saturated hydrocarbon group, R+s has 1 carbon number
-10 represents a divalent hydrocarbon group.

In the above compound (Z), it can be represented by R+t.

Specific examples of the compounds (Z) represented by the above general formulas (1) to (@) include 3.4-epoxycyclohexylmethyl acrylate and 3.4-epoxycyclohexylmethyl methacrylate. As these commercially available products,
For example, METHB, AETHB manufactured by Daicel Chemical Industries, Ltd.
(all are trade names), all of which have an epoxy group-containing functional group represented by the formula (1) or (TI). Furthermore, 4-vinylcyclohexene oxide can also be used as compound (Z).

Component (B) can be produced by polymerizing one or more selected from compounds (Z), but it is also possible to copolymerize the polymerizable unsaturation of the compound (Z).

The other polymerizable unsaturated polymers can be selected from a wide range depending on the desired performance of the resulting (co)polymer, and representative examples thereof are as follows.

(a) Esters of acrylic acid or methacrylic acid: for example, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate,
Hexyl acrylate, octyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate,
C1-18 alkyl esters of acrylic acid or methacrylic acid such as propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, lauryl methacrylate: methoxybutyl acrylate, ethoxybutyl methacrylate, Acrylic acid or methacrylic acid with 2 or more carbon atoms, such as methoxyethyl acrylate, methoxyethyl methacrylate, ethoxybutyl acrylate, and ethoxybutyl methacrylate
18 alkoxyalkyl esters: C2-8 alkenyl esters of acrylic acid or methacrylic acid such as allyl acrylate and allyl methacrylate, acrylic acids such as hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate-5. or C2-C8 hydroxyalkyl ester of methacrylic acid; C3-C18 alkenyloxyalkyl ester of acrylic acid or methacrylic acid such as allyloxyethyl acrylate and allyloxymethacrylate.

(b) Vinyl aromatic compounds: for example, styrene, α-methylstyrene, vinyltoluene, p-chlorostyrene.

(C) Polyolefin compound: For example, butadicyene, isoprene, chloroprene.

(d) Others: Acrylonitrile, methacrylonitrile, methyl isopropenyl ketone, vinyl acetate bivalate (Shell Chemicals), vinyl propionate, vinyl bivalate, vinyl compounds with polycaprolactone chains (e.g. FM-3x monomer) : Product name manufactured by Daicel Chemical Industries).

The composition ratio of compound (Z) and other polymerizable unsaturated molecules can be arbitrarily selected depending on the purpose. The group-containing functional group can be selected within the range of containing at least 2 on average, preferably 3 or more on average, more preferably 4 or more on average, but in order to use it as a functional group that imparts sufficient curability. In particular, the (B
It is preferable that the content of the compound (Z) in the solid content of component () is in the range of 5 to 100% by weight, more preferably 20 to 100% by weight.

The component (B) obtained by the third production method can be produced using the same method and conditions as those for polymerization reactions based on polymerizable unsaturated bonds in ordinary acrylic resins, vinyl resins, and the like. As an example of such a polymerization reaction, there can be shown a method in which each monomer component is dissolved or dispersed in an organic solvent and heated while stirring at a temperature of about 60 to 180°C in the presence of a radical polymerization initiator. One reaction time can usually be about 1 to 10 hours. Also.

As the organic solvent, alcohol solvents, ether solvents, ester solvents, hydrocarbon solvents, etc. can be used. When using a hydrocarbon solvent, it is preferable to use other solvents together from the viewpoint of solubility.Furthermore, any commonly used radical initiator can be used, and specific examples thereof include: Examples include peroxides such as benzoyl peroxide and t-butylperoxy-2-ethylhexanoate, and azo compounds such as butyl nitrile and azobisdimethylvaleronitrile.

Component (B) in the above third production example preferably has a number average molecule 1 generally in the range of about 3.000 to about 100.000 (7), particularly in the range of 4.000 to 10.000. The one in is more preferable.

Among the above-mentioned components (B), the ones that are suitable for use in applications that require high performance, such as cationic electrodeposition paints used for automobile bodies, are It has an average of 3 or more groups, more preferably an average of 4 or more, and most preferably an average of 5 or more groups, and has an epoxy equivalent of preferably 100 to 100.
2.000, more preferably 150-500, especially 15
0 to 250, and the number average molecular weight is preferably 400 to 100.000, more preferably 700.
~50.000. Particularly preferably 700 to 30,000
It is within the range of

The amount of component (B) to be used varies depending on the type of component (A) used, ranging from the minimum amount necessary for heat curing of the resulting coating film to the maximum amount that does not impair the stability of the cationic electrodeposition paint. Although it can be changed as appropriate within the range, generally the weight ratio of solid content of component (B) to component (A) is 0.2 to 1.0.
, especially 025 to 0.85, more preferably 0.25 to
It is preferable to select it within the range of 0.65.

In this composition, a part of component (B) may be added to component (A) in advance.

In the present invention, the resin (A) and the epoxy resin (B
Electrodeposition paints containing pigments, gelling fine particle polymers, etc. in addition to the above components can be used. Electrodeposition paints using this material can form a coating film with excellent rust prevention properties at the edges.

The electrodeposition paint containing the above-mentioned pigment contains at least one pigment in the paint, and the pigment has an oil absorption of 100%.
Contains at least 5% by weight of the above pigments, and the total oil absorption amount of the pigment is 1,000 to 10,00% per 100 parts by weight (solid content) of the total amount of the resin (A) and the epoxy resin (B).
0, preferably in the range of 3.000 to 7.000, can be suitably used.

As the silicon dioxide pigment having an oil absorption of 100 or more, for example, Nippon Aerosil Co., Ltd.'s product name [Erosil 200J
(Oil absorption 143-183), Fuji Davison product name [Thyroid 161J (Oil absorption 128-135)
), "Thyroid 244" (oil absorption 270-330),
"Thyroid 308J (oil absorption 170-220),
"Thyroid 404J (oil absorption 170-230),
Commercially available products such as Thyroid 978J (oil absorption 180-230) can be mentioned, and examples of carbon-based pigments include furnace-type or channel-type carbon black (usually used as a black pigment) (oil absorption 100-130). ) is used, for example, "Carbon BAGJ", a trade name of Columbia Carbon Company, USA.

Pigments to be blended include, in addition to the above-mentioned pigments with an oil absorption of 100 or more, pigments commonly used in electrodeposition paints, such as coloring pigments such as red iron, titanium white, carbon black, phthalocyanine blue, and phthalocyanine green; chromic acid. Corrosion-preventing pigments such as strontium and basic lead sulfate: Extender pigments such as talc, clay, and calcium carbonate have a total oil absorption of 1.000 to 10.0% per 100 parts by weight of the resin (A) and epoxy resin (B). They can be used together as long as they are within the range of 000.

The "oil absorption" and "total oil absorption" of pigments are based on JISK510.
1-78 (Pigment Test Method).

As an electrodeposition paint containing a gelled fine particle polymer, a cationic electrodepositable gelled fine particle polymer preferably having the following composition is blended into the paint in an amount of 500 em or less, preferably 10 to 300 em, and further Preferably 50-10
It can have an average particle size within the range of 0.00 m. The blending ratio of the particulate polymer can be appropriately selected depending on the required performance, but is usually 5 to 45 parts by weight based on 100 parts by weight (solid content) of the total amount of the resin (A) and the epoxy resin (B). It can be selected preferably within the range of 10 to 30 parts by weight.

Examples of the cationic electrodepositable gelling fine particle polymer include the following. These materials can be used alone or in combination of two or more.

■ Emulsion polymerization of a polymerizable monomer containing at least two radically polymerizable unsaturated groups in the molecule and a radically polymerizable unsaturated monomer other than the above using a reactive emulsifier containing an allyl group in the molecule. gelled fine particle polymer (as disclosed in JP-A No. 247107).

■ Using a cationic reactive emulsifier containing an allyl group in the molecule, as a first step, a polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group, at least 2 Emulsion polymerization of the monomer component (a) consisting of a polymerizable polymer containing radically polymerizable unsaturated groups, a polymerizable unsaturated monomer containing a vinyl double bond and a hydroxyl group, and other polymerizable unsaturated monomers. Then, in the presence of the aqueous gelatinized fine particle polymer obtained in the first step, as a second step,
Blocked mono- or polyisocyanates in which at least one isocyanate group in the molecule is blocked with a radically polymerizable monohydroxy compound, polymerizable unsaturated monomers containing a vinyl double bond and a hydroxyl group, and other polymerizable unsaturated monomers A gelatinized fine particle polymer (specially produced by emulsion polymerization of a monomer component consisting of No. 1-197929).

■ Polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group, block polyisocyanate in which at least two isocyanate groups are blocked with a radically polymerizable monohydroxy compound, vinyl double A gelled fine particle polymer (patent application Hei 1-
No. 197930).

■ Using a cationic reactive emulsifier containing an allyl group in the molecule, as a first step, a polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group, at least 2 A monomer component (c) consisting of a polymerizable monomer containing a radically polymerizable unsaturated group, a polymerizable unsaturated monomer containing a vinyl double bond and a hydroxyl group, and other polymerizable unsaturated monomers is emulsion polymerized. Then, as a second step, in the presence of the aqueous gelled particulate polymer obtained in the first step,
Blocked mono- or polyisocyanates in which at least one isocyanate group in the molecule is blocked with a radically polymerizable monohydroxy compound, polymerizable unsaturated molecules containing vinyl double bonds and hydroxyl groups, and amino groups in one molecule. A polymer of monomer component (d) with a core of a polymer of monomer component (c) obtained by emulsion polymerization of monomer component (d) consisting of a polymerizable unsaturated monomer and other polymerizable unsaturated monomers. Gelled fine particle polymer having a core-shell structure with a shell (Patent application No. 1-2)
65160).

■ Polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group, a block polyisocyanate in which at least two incyanate groups are blocked with a radically polymerizable monohydroxy compound, a vinyl double bond A polymerizable unsaturated monomer containing an amino group in the molecule and other polymerizable unsaturated monomers are emulsified using a cationic reactive emulsifier containing an allyl group in the molecule. Gelled fine particle polymer obtained by polymerization (Patent application No. 1-2)
66850).

Among the above-mentioned materials, it is preferable to use those described in (1) and (2).

The above-mentioned coloring pigments, extender pigments, anticorrosion pigments, and the like can be used as necessary in the electrodeposition coating containing the gelled fine particle polymer.

In addition, in the present invention, the cationic aqueous liquid (II) contains the resin (A) and the epoxy resin (B) as main resin components, and if necessary, pigments similar to those described above, It is a blend of gelatinized fine particle polymer, coloring pigment, anti-corrosion pigment, etc. As the aqueous liquid (II), the same one as the cationic electrodeposition paint (I) can be used.

In the present invention, the method of electrodepositing the cationic N-coated paint (1) on the object to be coated is not particularly limited, but for example, the cationic N-coated paint (1) has a solid content of about 5 to 40%. % by weight, preferably about 10 to 30% by weight, and further adjust the pH to about 5.5.
~9.0, preferably within the range of about 5.8 to 7.0, is used as an electrodeposition bath, and the bath temperature is adjusted to 15 to 35°C,
Electrodeposition can be carried out by immersing the object to be coated in the bath and then applying a voltage of 50 to 400 cm between the object to be coated and the counter electrode for about 1 to 5 minutes. The film thickness of electrodeposition coating is usually about 10 to 70P, preferably about 15 to 50
P (dry film thickness).

In the present invention, washing with water is performed after electrodeposition coating. Washing with water is usually deionized water, water is the limit for paint? It is carried out using filtrate or reverse osmosis filtrate.

Before the water-washed coating film is treated with the cationic aqueous liquid (II), it may be heated, for example, at about 80°C for about 30 minutes, or heated to the extent that water is forcibly removed using hot air, as necessary. You may do so.

The heating may be carried out until it reaches a semi-cured state.

In the present invention, if the bath paint is baked on the deposited coating without washing with water, the low neutralization and high concentration bath paint present near the deposited coating will cause wrinkles and unevenness on the cured coating. This is not desirable as it may cause

In the present invention, the method of treating the electrodeposition coating film using the cationic aqueous liquid (II) is a method other than electrodeposition coating, usually,
This is done by various methods such as sinking, dipping, and spraying. The film thickness to be treated is usually about 1 to 4 P, preferably about 2 to 30 P (dry film thickness).

The pH and solid content of the cationic aqueous liquid (II) are not particularly limited, but the solid content concentration is approximately 5 to 50% by weight.
, preferably in the range of 10-30% by weight, with a pH of about 5.
It can be adjusted to a range of 5 to 9.0, preferably 5.7 to 7.0.

The coating film treated with the cationic aqueous liquid (II) has a
It is hardened by baking at about 180°C. The total paint film thickness can be the total film thickness of the above-mentioned electrodeposition paint film thickness and the paint film thickness above it, but from the viewpoint of economy etc.
The range is 0F.

The paint film thus formed can be finished by further applying a top coat as necessary.

[Operation and Effects of the Invention] The coating film formed by the method of the present invention is obtained by electrocoating the object to be coated in a cationic coating in the first step, and washing the deposited coating film with water to form a porous coating film. is formed, and in the second step, by applying a cationic aqueous liquid on top of this coating, it easily impregnates the first-stage porous precipitated coating, resulting in a uniform coating with no pores. membrane can be obtained. Since the porous precipitated coating film itself has poor melt flowability when heated, the edge portions are covered with a thick coating and exhibits an excellent rust prevention effect. The cationic aqueous liquid present in the surface layer of the coating film exhibits an excellent smoothness effect due to the melt flow of the cationic aqueous liquid itself when heated.

In the present invention, if a cationic electrolyte containing a fluidity regulator (pigment such as silicon dioxide, gelled fine particles, etc.) is used to improve the corrosion resistance of the edges, a coating with particularly excellent edge rust prevention properties can be obtained. A film can be formed.

EXAMPLES The present invention will be specifically explained below with reference to Examples and Comparative Examples. "Parts" and "%" are "parts by weight" and "% by weight"
” means.

(A-1): 1,900 parts of bisphenol A type epoxy resin with an epoxy equivalent of 950 [trade name "Epicote 1004J, manufactured by Shell Chemical ■]" was dissolved in 993 parts of butyl cellosolve, and jetanol was added. After dropping 210 parts of amine at 80 to 100°C, 1
The mixture was maintained at 00°C for 2 hours to obtain (A-1) having a solid content of 68%, a primary hydroxyl equivalent of 528, and an amine value of 53.

(A-2) 950 parts of bisphenol A diglycidel ether with an epoxy equivalent of 190, 330 parts of epoxy resin XB-4122 (trade name, manufactured by Ciba Geigy) with an epoxy equivalent of 330,
456 parts of bisphenol A and 21 parts of jetanolamine
The temperature was raised to 120°C, and the epoxy value was 1.
After reacting until the concentration was 0.2 mmol/g, diluted with 489 parts of ethylene glycol motubutyl ether and cooled, 1 part of jetanolamine was added while maintaining the temperature at 90°C.
26 parts, 53.5 parts of the monoethanolamine adduct of the above N,N-dimethylaminopropylacrylamide, and N
- 18.5 parts of methylaminoethanol was added and the reaction was allowed to proceed until the viscosity increase stopped, yielding (A-2) having a resin solid content of 80%, a primary hydroxyl equivalent of 592, and an amide valence of 55.

EHPE3150 [Epoxy equivalent: 175-195, manufactured by Daicel Chemical Industries, Ltd. 132.6 parts and 8.2 parts of propylene glycol monomethyl ether were heated and dissolved at 100°C to obtain a solution with a solid content of 80% and an epoxy equivalent of 190. B-1) 40
．． I got 8 copies. The number average molecular weight of the resin was approximately 1.500.

1 unit equipped with a stirring device, a thermometer, a cooling tube and a heating mantle
In a flask of ε, 3507 parts of deionized water and an emulsifier (Latemni-180, manufactured by Kao Corporation, 25% aqueous solution quaternary ammonium chloride allyl group-containing cationic reactive emulsifier) 80
of the mixture was added, and the temperature was raised to 90°C while stirring. To this, 12.5 parts of a polymerization initiator (VA-086, manufactured by Wako Tsumugi Co., Ltd., 2.2'-azobis[2-methyl-N-(2hydroxyethyl)-propionamide]) was added to 500 parts of deionized water. A dissolved aqueous solution was added. After 15 minutes, the monomer mixture (
Styrene/n-butyl acrylate/1.6-hexanethiol diacrylate: 470/470/60 parts) was added for 7 hours at 90°C, and the solid content was 20
%, and an average particle diameter of 70 nm (measured with Coulter Calancou's Nanosizer N-4) was obtained.

222 parts of isophorone diisocyanate and 50 parts of methyl isobutyl ketone were placed in a flask equipped with a Gel 1 A2 pressure stirrer, an air introduction tube, a cooling tube, and a temperature control device, and the mixture was stirred while blowing dry air into the liquid phase. The temperature was raised to 70°C. Add 0.3 parts of dibutyltin dilaurate to this, and then add 2-
116 parts of hydroxyethyl acrylate was added dropwise over 1 hour, and the temperature was maintained at 70°C for an additional hour after the addition was completed. Subsequently, 115 parts of methyl isobutyl ketoxime was added dropwise over 1 hour. Even after the completion of the dropwise addition, the mixture was heated and maintained at 70°C, and the reaction mixture was collected over time and confirmed by -NGO absorption IR.
The end point of the reaction was defined as the point at which the absorption of NGO ceased. In this way, an incyanate compound having a 90% inphorone diisocyanate/2-hydroxyethyl acrylate/methyl isobutyl ketoxime block solution was obtained.

Next, 700 parts of deionized water and -180162 parts of the same lame as above were placed in a II2 flask equipped with a stirrer, a thermometer, a cooling tube, and a heating mantle, and the temperature was raised to 90° C. while stirring. To this was added an aqueous solution prepared by dissolving 2 parts of the same VA-086 as the polymerization initiator in 100 parts of deionized water. After 15 minutes, the following monomer mixture was added.

Styrene 32 parts n-butyl acrylate 32 parts 1,6-hexanediol 30 parts diacrylate 2-hydroxyethyl acrylate 4 parts KBM-
503 * 2 parts * γ-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) Polymerization was carried out at 90° C. for 6 hours. Next, the following mixture was added dropwise to this product.

Styrene 38 parts n-butyl acrylate 38 parts 2-hydroxyethyl acrylate 4 parts Incyanate compound obtained in the above production 22 parts Polymerization was carried out at 90°C for 2 hours.

In this way, a gelled fine particle polymer 2 having a solid content of 20% and an average particle diameter of 74 nm (measured with Coulter Nanosizer N-4) was obtained.

hf ee! 1. 91 parts (solid content) of the above component (A-1), 30 parts of component (B)
(solid content), Ostix lead 3 parts, titanium oxide (oil absorption 22) 24 parts, refined clay (oil absorption 43) 12 parts, and Thyroid 244 (manufactured by Fuji Devison, hydrated amorphous silicon dioxide pigment, oil absorption 300) Cationic electrodeposition paint 1 was prepared by blending 12 parts. The total oil absorption amount of pigment is (A-1)
and 3870 parts per 100 parts of component (B). The pH of the electrodeposition paint was adjusted to approximately 5.6 using a 10% formic acid aqueous solution. Further, the solid content concentration (20%) of the electrodeposition paint was adjusted using deionized water.

Cation Co2 In cationic electrodeposition paint 1, (A-1) component is added to (A-2
A cationic electrodeposition paint 2 was obtained using the same formulation as the cationic electrodeposition paint 1 except that the ingredients were replaced with 1).

Cation z3 91 parts (solid content) of component (A-1), 30 parts of component (B)
1 part (solid content), 3 parts of Ostix lead, 24 parts of titanium oxide, and 12 parts (solid content) of gelling fine particle polymer 1 were blended to make cation 1! A coating material 3 was prepared. The pH and solid content of the coating material were adjusted in the same manner as for the cationic electrodeposition coating material I.

11 [Company A Cationic electrodeposition paint 4 was used in the same formulation as cationic electrodeposition paint 3, except that in cationic electrodeposition paint 3, gelled fine particle polymer 1 was partially replaced with gelled fine particle polymer 2. Obtained.

Example 1 Cationic electrodeposition paint 1 was electrodeposited under the conditions shown in Table 1. After that, paint 1 similar to the above was applied on the uncured electrodeposited film as shown in Table-1.
It was spray painted and baked under the following conditions.

Example 2 Cationic electrodeposition paint 2 was electrodeposited under the conditions shown in Table-1. Thereafter, the same coating material 2 as above was spray-coated on the uncured electrodeposition coating film under the conditions shown in Table 1, and baked.

Example 3 Cationic electrodeposition paint 3 was electrodeposited under the conditions shown in Table-1. Thereafter, the same coating material 3 as above was spray-coated on the uncured electrodeposition coating film under the conditions shown in Table 1 and baked.

Example 4 Cationic electrodeposition paint 4 was electrodeposited under the conditions shown in Table-1. Thereafter, paint 4 similar to the above was spray coated on the uncured electrodeposited film under the conditions shown in Table 1 and baked.

Comparative Example 1 After electrodeposition coating using cationic electrodeposition paint 1 under the conditions shown in Table 1, it was washed with water and baked.

Comparative Example 2 Electrodeposition coating was performed using cationic electrodeposition paint 1 under the conditions shown in Table 1, and baked as it was without washing with water.

Comparative Examples 3 to 5 Cationic electrodeposition paints 2 to 4 were electrodeposited under the conditions shown in Table 1-1 and baked as they were without washing with water. However, the case using paint 2 corresponds to Comparative Example 3, the case using paint 3 corresponds to Comparative Example 4, and the case using paint 4 corresponds to Comparative Example 5.

Comparative Example 6 Cationic electrodeposition paint 1 was electrodeposited under the conditions shown in Table 1. After that, Ascavator MG500 (
Anionic water-based paint (manufactured by Kansai Paint ■, trade name) was spray-painted under the conditions shown in Table 1 and baked. Baking is 170
This was carried out at ℃ for 30 minutes.

Examples and comparative examples are summarized in Table 2.

Table-1 *l Painted surface smoothness Visually evaluate the finish of the painted surface.

[0: good, 0: very good, ■=slightly poor, △: poor,
x: Significantly inferior] *2 Sharpness The coated plates of Examples and Comparative Examples were further coated with 3'5P of aminoalkyd resin paint, and baked at 140°C for 15 minutes.

Using this test plate, the sharpness measuring device rTcRI-GGD
-166 type Gd meter” (sold by Japan Color Research Institute). Measured with the angle fixed at 55°.

*345° edge rust prevention A SPC mild steel plate is processed to an angle of 45°, subjected to surface treatment with Palbond 3050, and then subjected to the specified electrodeposition coating and used for the test. The rust prevention test was based on JIS Z2371 salt spray test. After the test, the presence or absence of spot rust was examined. [0: Good, ○: Fairly good, ■ Slightly inferior, Δ: Poor, ×: Significantly inferior] *4 Rust resistance in general parts Based on JIS 22371 salt spray test. *5 Water resistance Immersed in tap water at 40°C. After cross-cutting the coating film, it was peeled off using cellophane tape, and adhesion deterioration was visually examined.

[0: Good, 0: Very good, ◎: Slightly poor, △: Poor,
×: Significantly inferior] *6 Impact resistance JIS K5400-1979 6.13.3B method, 1 weight 500 in an atmosphere at 20°C
g, indicates the maximum height without causing paint film damage under the conditions of the tip radius of the center of impact in inches (cm).

The maximum value was 50 cm.

*7 The coated plates of the Accelerated Weather Resistance Examples and Comparative Examples were further coated with 35μ of aminoalkyd resin paint clear, and baked at 140°C for 15 minutes. This coated plate was subjected to a Sunshine Weather-Ometer for 20 hours, and after being immersed in water at 40°C for 20 hours, a cross cut was made on the coated plate and a peel test was performed using cellophane adhesive tape.This test was repeated and the time at which peeling occurred was determined. I looked into it.

Claims (1)

[Claims] [1] Resin (A) containing a hydroxyl group and a cationic group
and an epoxy resin (B) having an average of two or more epoxy group-containing functional groups per molecule, which is formed by bonding an epoxy group to an alicyclic skeleton and/or a bridged alicyclic skeleton, as the main resin component. Electrodeposition is carried out in a cationic electrodeposition paint (I), and then ■ the object to be coated is washed with water and remains uncured, containing the above resin (A) and the above epoxy resin (B) as main resin components. A coating film forming method characterized by treatment with a cationic aqueous liquid (II) and subsequent baking. [2] The coating film forming method according to claim 1, wherein the coating material (I) contains a pigment and/or a gelled fine particle polymer.