JPS60215016A - Aqueous resin dispersion - Google Patents

Abstract

PURPOSE:The titled dispersion excellent in dispersibility and capable of forming an excellent film when used as a can interior coating, prepared by dispersing a composite resin composition comprising a partially combined product between a specified acrylic resin and a specified aromatic epoxy resin and a specified phenolic resin in an aqueous medium. CONSTITUTION:A partially combined product (C) obtained by partially reacting an acrylic resin (A) of a weight-average MW of 3,000-80,000 containing 12- 70wt% monobasic carboxylic acid monomer units with an aromatic epoxy resin (B) of a number-average MW >=900 having, on the average 1.1-2 epoxy groups in the molecule is mixed with a phenolic resin (D) of the formula (wherein R1 is H, or a 1-12C alkyl, R2-3 are each H or methylol, and n is 1-3) in a hydrophilic solvent to obtain a carboxyl group-excess composite resin composition containing 2-40wt%, based on the total resin weight, component D. This composition is dispersed in an aqueous medium in the presence of NH3 or an amine in such an amount that the pH of the final composition is 4-11 (provided that the ratio between the solids of components A and B is 2:1-1:6).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aqueous resin dispersion, more particularly as a coating composition for baking on metals.

In particular, the present invention relates to an aqueous resin dispersion that can form an excellent film as a paint for the inner surface of a can.

Conventionally, it has been desired to shift paints for cans and anticorrosion paints to water-based paints from the viewpoint of resource saving, energy saving, and environmental pollution. As with the solvent-based type, epoxy resin-based ones have been mainly studied in water-based systems, and various methods have been proposed for dispersing epoxy resins in water.

For example, as a method for dispersing an epoxy resin in water using a surfactant, two methods are known: a method using an anionic surfactant and a method using a nonionic surfactant. However, in the former case, the oxirane ring opens during the emulsification process and storage, resulting in a decrease in reactivity and poor performance of the formed coating, and also causes problems of thickening and gelation during storage. On the other hand, in the latter case, from the viewpoint of bidispersity and storage stability, the system contains a considerably large amount of surfactant, and this surfactant affects the chemical and mechanical properties of the coating film formed. tends to have a negative impact on

As a solution to this problem, various self-emulsifying epoxy resins have been proposed in which epoxy resins are modified with acrylic resins and segments with emulsifying power are introduced into the molecules.

For example, JP-A-53-1228 discloses a grafted polymer obtained by polymerizing a monomer mixture containing a carboxylic acid monomer using a free radical generator such as benzoyl peroxide in the presence of an epoxy resin. It has been shown that epoxy resins can be stably dispersed in aqueous media containing bases. Japanese Patent Publication No. 53-14963
No. 55-9433 and JP-A No. 55-9433 G. A partial reactant containing an excess of carboxyl groups obtained by reacting an acrylic resin with a relatively high molecular weight aromatic epoxy resin is dissolved in an aqueous medium in the presence of ammonia or an amine. It has been shown that it can be stably dispersed in Japanese Patent Application Publication No. 55-3481,
and JP-A No. 55-3482 discloses that a carboxyl group-functional polymer is esterified with an epoxy resin in the presence of an amine esterification catalyst, and a compound that substantially does not functionalize the oxirane groups of the epoxy resin is self-emulsified in water using a base. Self-emulsifying epoxy ester copolymers are disclosed. In JP-A-57-105418 and JP-A-58-198513.

A basic compound is obtained by polymerizing a monomer mixture containing acrylic acid or methacrylic acid and a low-molecular compound having an epoxy group and an acryloyl group in one molecule, which is obtained by partially reacting an aromatic epoxy resin and (meth)acrylic acid. Disclosed is an aqueous dispersion composition obtained by neutralization with. Since the self-emulsifying epoxy resin obtained by the above technique does not contain a surfactant in the coating material, a strong coating film can be obtained by itself. Water-soluble amino resins and phenolic resins are blended into these paints when faster curing speed is required. For example, an appropriate amount of water-soluble amino resin can improve the curing speed without reducing the physical properties of the formed coating film.
In some cases, it is possible to obtain a desirable coating hardness by increasing the crosslinking density, especially when used as a coating for the inside of a can.

Due to heat sterilization, low molecular weight compounds originating from the amino resin were eluted into the contents of the can, posing a hygiene problem.

The present inventors have made extensive studies to overcome the above-mentioned problems, and as a result, have arrived at the present invention. Namely, the present invention is directed to an acrylic resin (A) containing 12 to 70% by weight of monobasic carboxylic acid monomer units as an essential component, an aromatic resin having an average of 1.1 to 2.0 epoxy groups in the molecule; A composite resin composition with an excess of carboxyl groups obtained by mixing a partially bound product (D) of a group-based epoxy resin (B) and a phenol resin (C) represented by the following formula is used as a final composition.
An aqueous resin dispersion obtained by dispersing in an aqueous medium in the presence of ammonia or amine in an amount such that H is 4 to 11.

(In the formula, R+ represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, Rs and RB represent a hydrogen atom or a methylol group, and n represents an integer of 1 to 3.)

The aqueous resin dispersion in the present invention is preferably.

-[Acrylic resin (A) formed by copolymerizing a copolymerizable heptamer mixture containing 12 to 70% by weight of a basic carboxylic acid monomer; -An average of 1.1 to 2.0 epoxy groups in the molecule; It is obtained by chemically bonding the aromatic epoxy resin (B) and the phenol resin (C).

The acrylic resin (A) is prepared by mixing a monomer mixture consisting of monobasic carboxylic acid monomers such as acrylic acid and methacrylic acid with other copolymerizable polymers in an organic solvent with azobisisobutyronitrile and penduyl. Using a common radical polymerization initiator such as peroxide,
It can be obtained by copolymerization at a temperature of 50°C.

The above copolymerizable polymers include methyl acrylate, ethyl acrylate, and isopropyl acrylate.

n-butyl acrylate, isobutyl acrylate.

n-amyl acrylate, isoamyl acrylate.

Acrylic acid esters such as n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, decyl acrylate, dodecyl acrylate, methyl methacrylate, propyl methacrylate, Mn-methacrylate
Butyl, isobutyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate.

Methacrylic acid esters such as 2-ethylhexyl methacrylate, decyl methacrylate, and dodecyl methacrylate, styrene, vinyltoluene, 2-methylstyrene, t
- Styrene threads such as butylstyrene and chlorstyrene, hydroxyethyl acrylate, and hydroxypropyl acrylate.

Hydroxy group-containing monomers such as hydroxyethyl methacrylate and hydroxypropyl methacrylate, N-methylol (meth)acrylamide, N-butoxymethyl (
It can be selected from one or more of N-substituted (meth)acrylic monomers such as meth)acrylamide, epoxy group-containing monomers such as glycidyl acrylate and glycidyl methacrylate, and acrylonitrile.

The amount of monobasic carboxylic acid monomer used is 12 to 70% by weight based on the total amount of monomers.

If the amount used is less than 12% by weight, the dispersion stability of the resin in an aqueous medium, the adhesion to metal and solvent resistance of the painted film, and the flavor suitability when used for the inside of a can will all deteriorate. Unfavorable, on the contrary,
If the amount used is more than 70% by weight, the viscosity of the reaction system becomes extremely high when polymerizing the acrylic resin (A), which not only makes manufacturing difficult, but also reduces the water resistance of the painted film and the inner surface of the can. If used, boiling resistance etc. will deteriorate.

The acrylic resin (A) preferably has a weight average molecular weight in the range of 3.000 to 80.000.

When the weight average molecular weight is less than 3.000, the crosslinking density of the coating film increases, which impairs processability.

Also, 40.000. In particular, when it is greater than 80.000, gelation tends to occur during reaction with the aromatic epoxy resin (B).

The aromatic epoxy resin (B) is obtained by condensing bisphenol A and epihalohydrin in the presence of an alkali catalyst, and contains an average of 1°1iVA to 2.0% per molecule.
0 (has a flit epoxy group and has a number average molecular weight of 3
00 or more, preferably 900 or more.

As a commercially available product, Epicoat 82 from Shell Chemical Co., Ltd.
8. Epicoat 1001°Epicoat l 004. Epicote l 007. Examples include Epicote 1009.

Further, as an aromatic epoxy resin, dehydrated castor oil and soybean oil fatty acid are added to the epoxy group of the above-mentioned bisphenol A type epoxy resin.

It is also possible to use a modified epoxy resin in which a vegetable oil fatty acid such as coconut oil fatty acid or a modifier such as bisphenol A is reacted.

The main components of the phenolic resin (C) according to the present invention are:
It is expressed by the following formula.

(In the formula, +R1 is a hydrogen atom or a C1-C12 alkyl group, Rx, Rz are a hydrogen atom or a methylol group,
n represents an integer from 1 to 3. ) Phenol resin (C)
is obtained by addition condensation of formaldehyde to alkylphenol in the presence of an alkali catalyst, but there is a method in which alkylphenol dialcohol is produced in high yield at a relatively low temperature of about room temperature to 60°C, and then condensation is proceeded. Any known synthetic means can be used.

As the alkylphenol, p-cresol is used.

0-cresol, p-ethylphenol, p-tert
-Butylphenol, p-octylphenol.

p-nonylphenol etc. can be used. The reaction conditions for producing such a phenol resin can be freely selected within a range that satisfies the above requirements. Of course, there is no problem even if the phenol resin (C) having a specific n number is reacted under reaction conditions that allow a high yield to be obtained, further purified by a conventional method, and used substantially as a single substance. It is also possible to prepare two or more types of alkylphenols with different types of alkylphenols or with different n numbers, and use them by mixing them. In addition to the phenol resin (C), known phenol resins can be used in combination. Phenol resins used in combination include resol type phenol resins and novolac type phenol resins, which have been used in conventional epoxy-phenol paints. These phenolic resins are phenolic resins (C
), that is, the range in which the characteristics are not impaired due to the use of

It can be used in an amount not exceeding about 50% by weight.

In the present invention, the acrylic resin-aromatic epoxy resin partial bond (D) contains -basic carboxylic acid monomer 1
An acrylic resin (A) formed by copolymerizing a copolymerizable monomer mixture containing 2 to 70% by weight and an average of 1.
It can be produced by partially reacting with an aromatic epoxy resin (B) having 1 to 2.0 epoxy groups. To prepare the acrylic resin-aromatic epoxy resin partial reaction product, the reaction mixture is heated at 60°C in the presence of ammonia or amine as described below in a hydrophilic organic solvent such as ethylene glycol monobutyl ether.
It is recommended to stir the mixture at 170°C for 10 minutes to 2 hours. The reaction can be controlled by measuring the oxirane percentage, measuring the viscosity increase, or by gel verminion chromatography.
This can be checked using a chart of molecular weight distribution (GPC).

Furthermore, if the reaction is carried out in a relatively high boiling point solvent such as hexyl cellosolve, butyl cellosolve, methyl cellosolve acetate, or ethyl cellosolve acetate at 120°C or higher, acrylic resin ( A partial reaction product of A) and aromatic epoxy resin (B) can be obtained.

The reaction can also be controlled by measuring the % oxirane. As a method for measuring oxirane%.

A known method is to add a predetermined amount of tetraethylammonium bromide solution to a sample solvent solution and titrate it with standardized perchloric acid using crystal violet as an indicator.
Is the above titration method applied to the epoxy resin-acrylic resin partial reaction product due to the inhibitory effect of the coexisting excess carboxyl group?

Since the end point of the titration is often unclear, proton N
Quantification by MR is convenient and preferred. In proton NMR, the methylene of the oxirane group is 2.5~2°! 11ppm
Therefore, track this peak area during the 9 reactions,
The reduction rate of oxirane groups can be determined by comparing the area with other reference peaks, such as the peak area of the proton of the benzene ring contained in the aromatic epoxy resin. At this time, if a monomer having a benzene ring is used in the acrylic resin, the amount must be taken into account in the calculation. The reduction rate of oxirane groups in the reaction stage is 5 to 95% relative to the oxirane content of the aromatic epoxy resin as a raw material.
, more preferably 30 to 70%. If the reduction rate of oxirane groups is less than 5%, the acrylic resin-aromatic epoxy resin partial reaction product cannot be sufficiently self-emulsified in the aqueous medium and tends to separate during storage, and if it is greater than 95%, the acrylic resin-aromatic epoxy resin partial reaction product tends to separate during storage. The processability of the film tends to deteriorate. In particular, aqueous resins obtained with oxirane groups in the range of 30 to 70% are excellent in coating suitability.

In the present invention, the acrylic resin-aromatic epoxy resin partially bonded product CD) contains 12 to 70% by weight of monobasic carboxylic acid monomer in the presence of the aromatic epoxy resin (B).
It can be obtained by polymerizing a copolymerizable mixture containing a copolymerizable compound using a relatively large amount of an organic peroxide such as benzoyl peroxide. In this case, an aromatic epoxy resin grafted with an acrylic resin is obtained.

The acrylic resin-aromatic epoxy resin partially bonded product (D) in the present invention also includes aromatic epoxy resin (B).
A copolymerizable monomer mixture containing 12 to 70% by weight of a compound having both an epoxy group and a double bond and a monobasic carboxylic acid heptamer in the presence of a base. can be obtained by polymerizing using a radical polymerization initiator.

The solid content ratio of the acrylic resin (A) and the aromatic epoxy resin (B) is selected from the range of 1:1 to 1:6.

In the present invention, the composite resin composition consists of an acrylic resin-aromatic epoxy resin partial bond (D) and a phenol resin (
C), preferably in a hydrophilic solvent.

The amount of phenolmeth resin (C) in the composite resin composition is 2 to 40% by weight based on the total amount of resin, and
If it is less than 40% by weight, the contribution to the curing speed of the coating film will not be sufficient, and if it exceeds 40% by weight, the physical properties such as processability of the coating film will tend to deteriorate.

It is sufficient to add ammonia or amine in an amount of 1 and disperse it in an aqueous medium, but if high boiling point solvents were used in the previous step, remove these solvents in advance under reduced pressure. It is preferable.

The above amine is, for example, trimethylamine.

Alkylamines such as triethylamine and butylamine, alcohol amines such as 2-dimethylaminoethanol, jetanolamine, triethanolamine, and aminomethylpropanol, 3-morpholine, and the like are used. Also ethylenediamine.

Polyvalent amines such as diethylenetriamine can also be used.

In the present invention, the aqueous medium is at least 10% by weight.
The above means water alone or a mixture with a hydrophilic organic solvent, and examples of hydrophilic organic solvents include methanol, ethanol, n-propanol, isopropanol, n-butanol, 5ec-butanol, tert-butanol, Alkyl alcohols such as isobutanol, ether alcohols such as methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl cellosolve, methyl carpitol, ethyl carpitol, ether esters such as methyl cellosolve acetate, ethyl cellosolve acetate, other dioxane, dimethyl formamide , dia-7ton alcohol, etc. are used.

The aqueous resin dispersion of the present invention has excellent curability because it uses a phenolic resin with excellent 9 reactivity.

The resulting coating has excellent extraction properties. It also has extremely high adhesion to metals.

The aqueous resin dispersion according to the present invention can be used as a paint by adding a surfactant, an antifoaming agent, etc. to improve coating properties, if necessary.

The applicable substrates include metal plates such as untreated steel plates, treated steel plates, galvanized iron plates, and tin plates, and the preferred coating method is air spray, airless spray, electrostatic spray, etc. Dip coating, roll caulk coating, electrodeposition coating, etc. are also possible. The baking conditions can be selected from a temperature range of 150°C to 230°C for 2 to 30 minutes per hour.

The aqueous resin dispersion of the present invention can also be used in rust-preventing primers, printing inks, anti-corrosion paints, etc. by adding appropriate rust preventive agents, pigments, fillers, etc., depending on the purpose.

The present invention will be explained below with reference to examples. In addition.

In the examples, "parts" and "%" are "parts by weight" and "% by weight," respectively.
” is shown.

Example 1 [Preparation of phenol resin solution] 136 parts of p-tert-butylphenol, 162 parts of 37% formaldehyde aqueous solution, and 160 parts of 25% sodium hydroxide aqueous solution were placed in a flask, reacted at 50°C for 3 hours, and then diluted with hydrochloric acid. and water was separated. After water separation,
250 parts of ptert-butylphenol, 3 parts of 10% hydrochloric acid
．． 7 parts and 250 parts of water were added and stirred for about 30 minutes, and when the heat generation was completed.

Add 160 parts of 25% sodium hydroxide and 120 parts of 37% formaldehyde aqueous solution, react at 50°C for 3 hours, neutralize with hydrochloric acid, separate the aqueous layer, and wash with water.

Repeat water separation 3 times, n-butanol/xylene/=
It was dissolved in a 1/1 mixed solvent to obtain a 60% phenol resin solution. As a result of analyzing the obtained resin by GPC, p
91% is a methylolated trimer of -tert-butylphenol, and the rest is a methylolated trimer of -tert-butylphenol.
A small amount of methylolated dimer and methylolated tetramer were contained.

[Adjustment of acrylic resin solution]

Styrene 300.0 parts Ethyl acrylate 210.0 Meccrylic acid 90.0 Ethylene glycol monobutyl ether 388.0 Benzoyl peroxide 12.0 A mixture of the above composition was placed in a tetrasol flask purged with nitrogen gas and heated to 80-90°C. Heat it up, and gradually add the remaining amount over 2 hours while keeping it at that temperature.After adding one drop,
After further stirring at that temperature for 2 hours, it was cooled and acid + il [
193 (solid content equivalent, same below), solid content 59.7%,
Viscosity: 4100 cps (all viscosities below 25°C are 25
A carboxyl group-containing resin solution was obtained.

(Preparation of epoxy resin solution) 500 parts of Epikote 1007 3 parts of ethylene glycol monobutyl ether 333 Pour the entire amount into a four-sol flask purged with nitrogen gas, gradually heat to raise the internal temperature to 100°C, and stir for 1 hour to completely dissolve. It was cooled to 80"C to obtain an epoxy resin solution with a solid content of 60%.

[Adjustment of aqueous dispersion]

■ 50 parts of the above acrylic resin solution ■ 100 parts of the above epoxy resin solution ■ 2-dimethylaminoethanol 4.8 ■ 30 parts of the above phenol resin solution ■ Ion exchange water 355.2 Charge ■ and ■ in a four-solo flask, stir, and then add ■. After addition and neutralization, the temperature was raised to 80°C, reacted for 30 minutes, and then cooled. The bond between the acrylic resin and the epoxy resin was confirmed by GPC measurements before and after the reaction. After cooling■
was added and stirred to make a homogeneous solution, and without further stirring, (2) was gradually added to obtain a milky white dispersion with a solid content of 20% and a viscosity of 425 cpS. The obtained dispersion was stored at 50°C for 3 months, but no abnormalities were observed.

Example 2 [Preparation of phenolic resin solution] A flask was charged with 162 parts of a 37% formaldehyde aqueous solution, and 160 parts of a 25% sodium hydroxide aqueous solution, and reacted at 50°C for 2 hours.
The temperature was raised to 00°C, and the reaction was further carried out at 100°C for 1 hour, neutralized with hydrochloric acid, and extracted with a mixed solvent of n-butanol/xylene-1/1 to obtain a 60% phenolic resin solution. As a result of analysis by GPC, more than 90% of the reaction product after 2 hours at 50°C was a dimethylol compound of p-cresol, and 9% of the final product was a methylol compound of p-cresol, and 36% was a dimethylol compound of p-cresol. Body methylol compounds, 41%
were methylolated trimers, 9% were methylolated tetramers, and 5% were methylolated pentamers or more.

An acrylic resin solution and an epoxy resin solution were prepared in the same manner as in Example 1.

[Adjustment of aqueous dispersion]

■ 50 parts of the above acrylic resin solution ■ 100 parts of the above epoxy resin solution ■ 4.8 parts of 2-dimethylaminoethanol ■ 30 parts of the above phenol resin solution ■ Ion exchange water 355.2 Place ■ and ■ in a four-eye flask and stir. After neutralization by adding (2), the temperature was raised to 80°C, reacted for 30 minutes, and then cooled. The bond between the acrylic resin and the epoxy resin was confirmed by GPC measurements before and after the reaction. After cooling, ■ was added and stirred to make a homogeneous solution. Without further stirring, ■ was gradually added, resulting in a solid content of 20% and a viscosity of 3.
A milky white dispersion of 90 CpS was obtained. The obtained dispersion was stored at 50°C for 3 months, but no abnormalities were observed.

Comparative Example 1 An acrylic resin solution and an epoxy resin solution were prepared in the same manner as in Example 1.

[Adjustment of aqueous dispersion]

■ 50 parts of the above acrylic resin solution ■ 100 parts of the above epoxy resin solution ■ 2-dimethylaminoethanol 4,8 ■ Ion-exchanged water 295.2 Charge ■, ■, and ■ into a four-solo flask, raise the liquid temperature to 80°C, and do so for 30 minutes. The mixture was allowed to react and cooled. The reaction between the epoxy resin and acrylic resin was confirmed by GPC measurements before and after the reaction. When I gradually added ■ without further stirring, the solid content was 20.
%, a milky white dispersion with a viscosity of 362 cpS was obtained. No abnormalities were observed in the obtained dispersion when it was stored at 50°C for 3 months.

Comparative Example 2 [Preparation of phenolic resin solution] 136 parts of p-tart butylphenol, 162 parts of 37% formaldehyde aqueous solution, and 80 parts of 25% sodium hydroxide aqueous solution were placed in a flask and reacted at 100°C for 2.5 hours, then treated with hydrochloric acid. After neutralizing.

It was extracted with a mixed solvent of n-butanol/xylene-1/1 to obtain a 60% phenol resin solution. As a result of GPC analysis, 8% of unreacted p-tert-butylphenol, p
-16% methylolated product of 1ert butylphenol,
The methylolated products were 21% of dimers to tetramers, and 55% were methylolated products of pentamers or more.

The same procedure as in Example 1 was conducted except that the acrylic resin solution and epoxy resin solution were used in the Example. The resulting dispersion had a solids content of 20% and a viscosity of 412 cps.

Comparative Example 3 An acrylic resin solution and an epoxy resin solution were prepared in the same manner as in Example 1. Also, the preparation of aqueous dispersion.

Cymel 325 instead of 30 parts of phenolic resin solution
The same procedure as in Example 1 was carried out except that 22.5 parts of a water-meltable amino resin (manufactured by Mitsui Toatsu Oren, solid content: 80%) was used.

The resulting aqueous dispersion had a solids content of 20% and a viscosity of 386 cp.
It was s.

Examples 1-2. The aqueous dispersions obtained in Comparative Examples 1 to 3 were applied onto a tin plate to a thickness of 8 to 10 μm, and baked and dried at 165° C. and 200° C. for 5 minutes each to prepare test panels. The results of various resistance tests are shown in Table I. In addition, the above water-based dispersion was applied by spraying to the inner surface of a 2-piece tin can with a content capacity of 250 m1, and baked at 165°C and 200°C for 5 minutes each to dry to create an inner-coated can and test its various resistances. did. The results are shown in Table H.

From Table I and Table ■, Examples 1 and 2 and Comparative Examples 2 and 3 containing phenolic resin or melamine resin were found to be superior to Comparative Example I in the retort resistance, corrosion resistance, and saline storage tests.
shows better performance. However, Example 1
．． In comparison with Comparative Example 2.3, Sample No. 2 had an extremely small amount of potassium permanganate consumed, had excellent extraction characteristics, and had excellent flavor retention.

The various test methods in Table I and Table ■ are as follows.

(11 Adhesion: Approximately 1.5 m using a knife on the coating surface
Make 11 vertical and horizontal cuts into the gopan using m rp. Adhere 24mm wide cellophane adhesive tape 5
The number of unpeeled gopan eyes when strongly peeled is expressed in the numerator.

(2) Retort resistance: After treatment in water at 125°C for 30 minutes.

The coating film is judged visually and by peeling off the cellophane adhesive tape.

(3) Workability: This occurs when a special fold-type DuPont impact tester is used, a sample folded in half is placed at the bottom, and an iron weight with a flat contact surface weighing I kg is dropped from a height of 50 cm. The length of the crack in the paint film at the bent part was measured.

0-10 division ・　・　・・　○ mark 10-20 fins...△ mark 20 mm or more... Indicated by an x mark.

(4) A test piece with an x mark made on the coating surface using a knife was treated in 1% saline at 125°C for 30 minutes.
Determine the degree of corrosion near the X mark.

Items with no abnormality...○ Items with slight corrosion...△ Items with significant corrosion...
... × (5) Potassium permanganate consumption: Fill the inner-coated can with 250 ml of ion-exchanged water, tighten 3 times, and
The samples were treated at 0°C for 30 minutes and at 100°C for 30 minutes, and measured according to the test method described in 1 Food Sanitation Law.

6) Salt solution storage test: 1% salt solution 25% in a can with internal coating
After filling 0ml and tightening once, pack them into a cardboard box (15 cans in a 30-can-sized box). Vibrate with a vibrator for 5 hours to cause the cans to collide with each other, then store at 25℃ for 1 month. did. The above test cans were opened and the amount of iron eluted into the saline solution was measured by atomic absorption spectrometry. (n: average of 15) (7) Flavor retention: 250 m of ion-exchanged water in a can with internal coating
1 was filled and sealed, and after sterilization at 100°C for 30 minutes, the solution in the can was further stored at 50°C for 6 months, and a flavor test was conducted on the solution in the can.

No change at all...Q There are some changes...△ There was a significant change...indicated by ×.

Example 3 [Adjustment of epoxy resin] Adjustments were made in the same manner as in Example 1.

[Adjustment of aqueous resin dispersion]

■ The above epoxy resin solution 150 parts ■ Butyl cellosolve 30 ■ Methacrylic acid 30 ■ Styrene 18 ■ Ethyl acrylate 2 ■ Benzoyl peroxide 3.5 ■ Phenol resin solution of Example 2 30 ■ 2-dimethylaminoethanol 4.8 parts ■ Ion Replacement water 560 Pour 560 ■ and ■ into a Yotsuro flask, stir, and lower the liquid temperature to 1
Raise the temperature to 15°C. Next, the mixture from (1) to (2) was added dropwise over a period of 1 hour, and the mixture was reacted at 115°C for an additional 2 hours. After cooling, (1) and (2) were added, and after stirring, (2) was gradually added to obtain a stable aqueous dispersion.

Using the obtained aqueous resin dispersion, tests similar to those shown in Table I2 and Table ■ were conducted, and as a result, excellent properties were obtained in all items.

Procedural amendment (spontaneous) April 2r, 1985 Director General of the Japan Patent Office 1, Indication of case Patent Application No. 70134 of 1988 2
, Title of the invention Aqueous resin dispersion 3, Relationship with the case of the person making the amendment Contents of the amendment 1, Patent claims Correct the range as shown in the attached sheet.

2. Specification, page 6, lines 2-3 [Acrylic resin (A), J is "acrylic resin (A)"]
"," he corrected.

3. Line 4 of page 6 of the specification r　2. Correct OJ to "2.0 pieces".

4. On page 6, lines 4-5 of the specification, "of epoxy resin (B)" is corrected to "with epoxy resin (B)."

5. In the third line from the bottom of page 1 of the specification, "alkylphenol dialcohol" is corrected to "dimethylolated product of alkylphenol."

6. Specification, page 12, line 5 r　2. Correct OJ to "2.0 pieces".

7. Specification page 18, last line to page 19, line 2: ``91% of the product is methylolated trimer, and the rest is methylolated monomer, methylolated dimer, and methylolated tetramer. ``Methylolated compound'' is corrected as follows.

"91% of the products are dimethylolated trimers, and the rest are dimethylolated l-mers, dimethylolated dimers, and dimethylolated tetramers" 8, page 21 of the specification, lines 9-6 from the bottom [Methylolated product, 36% dimeric methylolated product,
41% is a methylolated trimer, 9% is a methylolated tetramer, and 5% is a methylolated pentamer or more] is corrected as follows.

“Dimethylolated product, 36% dimer dimethylolated product, 41% trimer dimethylolated product.

9% is a dimethylolated product of a tetramer, 5% is a dimethylolated product of a pentamer or more.'' 9, Page 23 of the specification, lines 5 to 3 from the bottom, ``16% of a methylolated product, 21% a methylolated product of a 2-4mer. %, 55% methylolated product of pentamer or more” is corrected as follows.

"16% of dimethylol compounds, 21% of dimethylol compounds of dimers to tetramers, 55% of dimethylol compounds of pentamers or more" 10. Specification, page 26, line 7 r (4) J and "on the coating surface" Insert the following words between.

"Corrosion resistance:" 11. Specification page 28, line 10: “Properties have been obtained.

” and “Table 1” on page 29, insert the following sentence.

[Example 4 (Preparation of phenol resin solution)] 460 parts of 11% sodium hydroxide aqueous solution was charged into a flask, and while stirring, 92% parabomaldehyde 12
After adding 8 parts little by little and dissolving p-cresol 108
2 hours at 50'C, followed by 70'C.
Let it react for 6 hours.

After neutralization with hydrochloric acid, the slurry washed with water was extracted with n-buknol to obtain a 30% phenol resin solution. As a result of analysis by GPC, 2% was dimethylolated p-cresol, 90% was dimethylolated dimer, 5% was dimethylolated trimer, and 3% was dimethylolated tetramer or higher.

[Preparation of aqueous dispersion]

■ Acrylic resin solution of Example 1 50 parts ■ Epoxy resin solution of Example 1 Loo parts ■ 2-dimethylaminoethanol 4.8 parts ■ The above phenol resin solution 60 parts
Part ■Ion-exchanged water 325.2 Department ■ and ■ were placed in a Solo flask, stirred, and neutralized by adding ■.The mixture was heated to 80° C., reacted for 30 minutes, and then cooled. The bond between the acrylic resin and the epoxy resin was confirmed by GPC measurements before and after the reaction. After cooling, ■ was added and stirred to make a homogeneous solution, and without further stirring, ■ was gradually added, resulting in a solid content of 20% and a viscosity of 4.
A milky white dispersion of 25 cpS was obtained. The obtained dispersion was stored at 50°C for 3 months, but no abnormalities were observed.

Example 5 [Preparation of acrylic resin solution] ■Methyl cellosolve acetate 1000 parts ■Styrene 180.6 parts ■Ethyl acrylate 86 parts ■Methacrylic acid 163 parts ■Hendyl peroxide 6.4 parts Reflux condenser, monomer tank, monomer flow rate A four-solo flask equipped with a steamer, a temperature needle, and a stirrer was replaced with nitrogen.
I prepared ■. In the monomer tank, ``monomer mixture■
～■ and the polymerization catalyst ■ are mixed together, and a quarter of the mixture is added to ■ in the above flask and gradually heated to 105
It was kept at °C.

The remaining mixed monomers were added over 2 hours, and after the completion of 9 dropwise additions, the mixture was stirred for an additional 2 hours and then cooled to room temperature.

The obtained solution had a solid content of 30.1%, a viscosity of UV <Gardner bubble viscometer, 25°C), and an acid value of 247 mgKO.
It was an acrylic resin solution of II/g (solid content equivalent).

[Preparation of epoxy resin-acrylic resin partial reactant solution]

■Methyl cellosolve acetate 2,100 parts ■Epikote 1009 900 parts ■Above acrylic resin solution 1,000 parts A stirrer, a reflux condenser, and a thermometer are placed in a flask.

And after installing a solvent removal device and purging with nitrogen.

Add (2) and (2), heat to 110°C, and continue stirring.

After completely melting the epoxy resin, add ■ and heat to 135°C.
The mixture was heated to a temperature of 100.degree. C. and stirred for 8 hours while maintaining this temperature to obtain an epoxy resin-acrylic resin partial reaction product. During this period, samples were taken out periodically to check their viscosity. At the end of the reaction, the solution had a solid content of 30.1% and a viscosity of UV. Thereafter, a portion of the solvent was removed under reduced pressure to obtain a solid content of 60%.

C) Preparation of aqueous dispersion) ■The above epoxy resin-acrylic resin partial reactant 500
Part [Phase] Phenol resin solution of Example 4 100 parts 02
5% ammonia water 19.5 parts @ ion-exchanged water 1180.5 Department In a solo flask, charge ■ and [phase], without stirring■
was added. After stirring for 30 minutes, @ was slowly added to obtain a yellowish milky white dispersion with a solid content of 20% and a viscosity of 480 cps.The obtained dispersion was stored at 50°C for 3 months, but no abnormalities were observed. I got angry.

Example 6 [Preparation of epoxy acrylate resin solution] ■Ebiko)
1009 646 parts ■ Ethylene glycol monobutyl ether 349 parts 0 10% sodium hydroxide solution 1 Good ■ Hydroquinone 0.02 parts ■ Methacrylic acid 4 parts ■ and ■ were charged and stirred at 110° C. for 2 hours, and after confirming dissolution, was cooled. ■■ was added at 100°C, and after heating, ■ was added. Reacted at 130'C for 5 hours, acid value was 0.3 mg
The process was terminated when the concentration decreased to KOH/g (in terms of solid content), and the mixture was cooled and taken out. -The number average molecular weight of the parabolite is 38
00. The epoxy equivalent was 275o, and the number of epoxy groups per molecule was 1.38 on average.

Solids content: 65%, viscosity at 50°C: 80,000 cp
It was s.

[Cleavage of aqueous dispersion]

■Methyl ethyl ketone 4o parts ■The above epoxy acrylate resin solution 158.5 parts ■Styrene 15.4 parts ■Ethyl acrylate 18 parts [Phase] Methacrylic acid 18 parts ■Ethylene glycol monobutyl ether 68.3 parts @Azobisisobutyronitrile 0 .5 parts @ Azobisisobutyronitrile 0.6 parts ■ Phenol resin solution of Example 4 57.3 parts ■ Methyl ethyl ketone 10 parts [Phase] 10% aqueous solution of dimedylaminoethanol 70 parts O-ion-exchanged water 543.4 Part ① was placed in a flask, heated and refluxed, and the mixed solutions ① to ＠ were added little by little over 3 hours.

After the addition was completed, the temperature was raised to 90°C, and (2) was added to continue the reaction. It was sampled and cooled when the solid content reached 55% or more. After cooling, add @, ■ and [phase].

After 15 minutes, O was added little by little and the solid content was 20%.
, an aqueous dispersion with a viscosity of 15 cps was obtained.

Regarding the aqueous dispersions obtained in Examples 3-6.

A coating test was conducted in the same manner as in Example 1. The test results are shown in Table 1 and Table H. 12. The first column from the top of Table ■ on page 29 of the specification [Potassium permanganate consumption]
m) Correct it as J.

13. Insert the appendix "Table ■" and "Table ■" between Table ■ and "Patent Applicant" on page 29 of the specification.

Claims: 1.1 to 70% by weight of an acrylic resin (A) containing monobasic carboxylic acid monomer units as an essential component; - an average of 1.1 to 2.0 epoxy groups in the molecule; A carboxyl group-excess composite resin composition obtained by mixing a partially bound product (D) with an aromatic epoxy resin (B) having An aqueous resin dispersion which is dispersed in an aqueous medium in the presence of ammonia or amine in an amount of 4 to 11.

(In the formula, R1 is a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, Rz and R3 are a hydrogen atom or a methylol group, and n is an integer of 1 to 3.) 2. Acrylic resin - aromatic epoxy resin Partially bonded product (D) is an acrylic resin with an excess of carboxyl groups obtained by partially reacting an acrylic resin (A) and an aromatic epoxy resin (B).
The aqueous resin dispersion according to claim 1, which is a partial reactant of an aromatic epoxy resin.

3. Acrylic resin (A> and aromatic epoxy resin (B)
) The aqueous resin dispersion according to claim 2, having a solid content ratio of 2:1 to 1:6.

4. The aqueous resin dispersion according to claims 1 to 3, wherein the weight of the phenolic resin (C) is 2 to 40% by weight based on the total weight of the resin.

5. The weight average molecular weight of the acrylic resin (A) is 3000
80,000 to 80,000.

6. The aqueous resin dispersion according to claims 1 to 5, wherein the aromatic epoxy resin has a number average molecular weight of 900 or more.

Claims (1)

[Claims] Acrylic resin (A) containing 1.12 to 70% by weight of monobasic carboxylic acid monomer units as an essential component, - aromatic epoxy resin having an average of 1.1 to 2.0 epoxy groups in the molecule; A composite resin composition with an excess of carboxyl groups obtained by mixing the partially bound product (D) of (B) and the phenol resin (C) represented by the following formula is adjusted to a pH of the final composition.
An aqueous resin dispersion, which is dispersed in an aqueous medium in the presence of ammonia or amine in an amount of from 4 to 11. (In the formula, R+ represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R@ represents a hydrogen atom or a methylol group, and n represents an integer of 1 to 3.) 2. Acrylic resin - aromatic epoxy An acrylic resin with an excess of carboxyl groups, in which the resin partially bound product (D> is obtained by partially reacting an acrylic resin (A) and an aromatic epoxy resin CB).
The aqueous resin dispersion according to claim 1, which is a partial reactant of an aromatic epoxy resin. 3. Acrylic resin (A) and aromatic epoxy resin (B)
) The aqueous resin dispersion according to claim 2, having a solid content ratio of 2:1 to 6:1. 4. The aqueous resin dispersion according to claims 1 to 3, wherein the weight of the phenolic resin (C) is 2 to 40% by weight based on the total weight of the resin. 5. The weight average molecular weight of the acrylic resin (A) is 3000
The aqueous resin dispersion according to any one of claims 2 to 4, wherein the aqueous resin dispersion has a molecular weight of 500 to 500. 6. The aqueous resin dispersion according to claims 1 to 5, wherein the aromatic epoxy resin has a number average molecular weight of 900 or more.