JPS6081261A - Resin composition for coating material - Google Patents

Abstract

PURPOSE:The titled composition, obtained by neutralizing a specific resin prepared by condensing a specific component, e.g. sorbic acid, etc. with an amine or alkali, and disperising or dissolving the resultant neutralized resin in water, capable of giving cold curable coating films having improved corrosion resistance, and suitable for electrodeposition. CONSTITUTION:A resin composition obtained by neutralizing an anionic resin, having 1,000-6,000 number-average molecular weight, 5,000-200,000 weight-average molecular weight and 25-100 acid value, and prepared by condensing (A) 1-10wt% sorbic acid with (B) 1-10wt% malice anhydride, (C) 1-30wt% epoxy resin having >=500mol.wt., preferably glydicyl ether type epoxy resin of bisphenol A, (D) 20-60wt% unsaturated fatty acid, e.g. linseed oil fatty acid, and (E) 0- 70wt% total of mono--trifunctional organic acid, e.g. acetic acid, and mono-- tetrahydric alcohol, e.g. amyl alcohol, with an amine or alkali, and dispersing or dissolving the neutralized resin in water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water-dispersible or water-soluble paint resin composition that provides a coating film with superior low-temperature curability and excellent corrosion resistance.

More particularly, the present invention relates to a coating resin composition particularly suitable for electrodeposition comprising an anionic resin prepared from sorbic acid, maleic anhydride, an epoxy resin and an unsaturated fatty acid.

Conventionally, anionic electrodeposition paints have been used for various purposes as primers. However, such a paint requires a high temperature of 160 to 180°C to be sufficiently cured, and is not suitable from the viewpoint of energy saving. In order to improve these drawbacks, efforts have been made to develop low-temperature, single-use anionic electrodeposition paints, but the current situation is that nothing useful has yet been found.

As a result of intensive research aimed at developing a low-temperature curing resin for coatings, the present inventors discovered that a low-temperature curing resin obtained from a condensate containing sorbic acid, maleic anhydride, epoxy resin, and unsaturated fatty acids as essential components was discovered. They discovered that it provides a coating film with excellent properties and good corrosion resistance, and is suitable as an anionic electrodeposition paint, and thus completed their invention.

That is, according to the present invention, 1 to 10 M% of sorbic acid, 1 to 101% of maleic anhydride, 1 to 30% by weight of an epoxy resin with a molecular weight of 500 or more, 561% by weight of unsaturated fat ribs, and 1 to 60% by weight of unsaturated fat ribs. Tsuru average molecular weight 1.000-G, 000, weight molecular weight 5.000-200 obtained by combining trivalent tuna and mono- to tetravalent alcohol (total weight 0-70) ,000, the product with a value of 25-100 is dispersed in water by amine or alkaline neutralization or is made of a squid Illii composition suitable for coatings, especially for electrodeposition coatings. The proboscis is provided.

Regarding conventional wearable resin compositions, there are many 4.1 papers, some review articles, such as "Petroleum and Petrochemicals J18 (3), 101-105 (1974) or [Pigment Technology J1973 ( 1), 155 to 164, etc.However, all of these have various drawbacks, for example, in the case of the composition of Japanese Patent Publication No. 51-32655, the coating film is dried at 170°C. The disadvantage is that it takes 30 minutes.

Also, J, oil Col, Chem, As5oc,
, 53.353-362 (1970), “Ro
omTemperature Crbring Ele
Ctrocleposited Coatings J discloses an electrodeposition coating that cures at room temperature, but this is a two-component system, and one electrodeposition coating cannot be used for a long period of time. On the other hand, the electrocoating composition according to the invention is moldable, stable for a long time, and has an IQ of 80 to 1 (IQ"
It differs from conventional electrodeposition coating compositions in that it provides sufficient hardness, reparative properties and other general coating film properties when dried at a low temperature of C.

Sorbic acid and maleic anhydride, which are raw materials for the resin composition of the present invention, may be added separately, or may be added as a Diels-Alder adduct of sorbic acid and maleic anhydride. Sorbic acid and maleic anhydride each have 1
~lO weight factor should be used. In either case, if the weight is less than 1 weight φ, the effect is small, and if the weight is 10 weight φ or more, it is easy to cause caking. The mol of sorbic acid and maleic anhydride do not necessarily have to be equimolar, but 1.5 to 0.8 mol of maleic anhydride per mol of sorbic acid is effective.

As the fatty acid used in the present invention, drying oil fatty acids having an iodine value of 130 or more are suitable. Such dry fatty acids include linseed oil)
? 1fl Sukufuran, Inuzume, etc. are included. In addition to drying oil fatty ridges, semi-drying oil with an iodine value of 100 to 1300, Si 1.
For example, cotton leaf oil, rapeseed oil, rice bran oil, etc., or non-drying oils with an iodine value of 100 or less, such as fatty acids such as palm oil and coconut oil, may be used.

One or more of these fatty acids may be used. However, in order to obtain sufficient normal temperature drying properties, the resin composition of the present invention must be contained in a fatty acid-deficient resin raw material having at least one unsaturated carbon-carbon bond in an amount of 20 to 60% by weight. If it is less than 20, sufficient normal temperature drying properties cannot be obtained, and if it is more than 60, the initial hardness is low. More preferably, the resin raw material should contain 30 to 50% fatty acid by weight. The above-mentioned fatty acids may be introduced directly as fatty acids [7], or may be added as glycerin esters (oils and fats) of fatty acids.

As the epoxy resin used in the present invention, a diglycidyl ether type epoxy resin of bisphenol A is suitable, and the epoxy resin must have a molecular t'r: i of 1.1500 or more. If it is less than 500, sufficient quick-drying properties and 6 degrees of history cannot be obtained. Other epoxy resins include bisphenol F1
Polyglycyl ethers such as phenol novolak and cresol novolak with a melting point of 40°C or higher can be used. The resin composition must contain at least 1 to 30% of the above-mentioned epoxy resins.

For epoxy resins with low molecular weights (500-1.000), 10-30% by weight is desirable, and for epoxy resins with high molecular weights (2,000-7.000), 1-20% by weight. The weight staff is promising.

In addition to the above-mentioned raw materials, the composition of "Mizumotori" includes mono- to trivalent acids used as raw materials for ordinary alkyds and mono- to trivalent acids.
A tetrahydric alcohol may be included as a raw material. Finally,
Number average molecular weight) 1. o o o ~ 6,000, frost amount average molecular j: 'f 5.000 ~ 200.000 I/C to add 1.25 ~ 100, necessary 1 inch 1
~ Trivalent acid, 1 to 41 pieces of alcohol each
! Using the above, product (/7) can be synthesized.

Examples of the monovalent to trivalent enemies mentioned above include aliphatic Cal71 of iJ7? Acetic acids, such as acetic acid, butyric acid, oleic acid, various aromatic carboxylic acids such as benzoic acid, tert-cutyl benzoic acid, phthalic acid, isophthalic acid, and other dimer acids, unique fatty acids and maleic acid. additions, or trimerite enemies. Examples of the above-mentioned mono- to tetrahydric alcohols include various aliphatic alcohols, such as tert-butyl alcohol, amyl alcohol,
Examples include 2-ethylhexyl alcohol, various aromatic alcohols such as benzyl alcohol 'IL'C, ethylene glycol/pepropylene glycol, neopentyl glycol, glycerol, trimethylolethane, pentaerythritol and the like.

The resin of the present invention can be synthesized by reacting the above raw materials all at once or in several batches. These reactions include, in addition to the Diels-Alder addition reaction,
These include addition or condensation reactions between alcohol groups, carboxylic acid groups, carboxylic anhydride groups, and epoxy groups, and polymerization reactions between unsaturated fatty acids.

The Diels-Alder reaction is generally carried out in parallel at temperatures above 50°C. Maleic anhydride (ηyp53°C1bp20
2℃) and norbic acid (mp 135℃, decomposition point 228℃)
It is important to carry out the Diels reaction at 140 to 190'C. Since the ring-opening reaction of Lr-oxy resin with carboxylic acid is promoted by an amine-based melting medium, a high 7-point amine such as dimethylbenolamine is used as the Z between the epoxy groups. . -O. . . It is effective to add it. The esterification reaction between alcohol group and carboxyl group is 150 to 250
It is unreasonable to do it at ℃. At temperatures above 200°C, the reaction of the unsaturated carbon-charcoal 5 double bonds of the unsaturated fatty acid and norbic acid becomes significant, so it is necessary to control the reaction temperature to avoid excessive reaction. In particular, since oxygen in the reaction system reacts with carbon-carbon double bonds, it is necessary to proceed with the reaction under an atmosphere of inert gas (nitrogen, carbon dioxide, etc.).

The reaction is carried out using a predetermined molecular weight (number average 1.00 (1 to a,
o o o) or when the viscosity or acid value higher than that is reached, the process can be stopped by lowering the temperature or mixing a water-soluble solvent or the like. The water-soluble solvent that can be used is preferably an alkanol such as methanol, ethanol, clobyl alcohol, monoargyl ethylene glycol, monoargyl ethylene glycol, etc., but other water-soluble solvents may also be used. , the j”
E, aceto/, THF, dioxane, etc. can also be used.

Aqueous bath solution for benthic acids (A): Neutralize with neutralizing agents, such as organic amines such as triethylamine and ethanolamine, or ammonia, and sodium hydroxide, and add to deionized water. By adding , a stable aqueous solution or dispersion can be obtained.

The dispersion referred to herein generally consists of a resin phase having a particle size of 10 μm or less and a continuous aqueous phase. This dispersion may be optically transparent or opaque.

When performing electrodeposition coating, this aqueous solution or dispersion is
First, a container is filled so that the isoelectric cathode and the conductive anode to be coated are immersed in the container, and then a voltage is applied between both L electrodes to coat the viscous film of the coating composition. Electrodeposit it on top. Voltage conditions are 1-1000V, typically 50-3
It is 00V. The electrolyte density usually decreases to a maximum of 0.1 during the electrodeposition process.
Upper A/criK will decrease from 770 units. ρB can usually be set to 7 to 10. Electrodeposition coating with the composition of the invention is suitable for tetraelectric substrates such as iron, aluminum, copper, etc.

Curing and drying of the adhesive film is usually carried out at 120 to 200'C, but when the composition of the present invention is used, the temperature is 60 to 100'C.
It is possible even at 20°C, and sufficient hardness, corrosion resistance and other physical properties can be obtained.

The paint according to the present invention can be applied to lj and li coated objects other than full flexure using any coating method such as brush coating, spray coating, roller coating, dip coating, etc. It is most suitable for electrodeposition coating on exclusive electric gold products such as those mentioned above.

Next, the present invention will be specifically explained using Examples and Comparative Examples. Percentage and parts (-1: weighted 2 points).

Example 1 N2 "In a reaction vessel with 2 exchanges, linseed oil fatty acid 315
Heat part to 180°C. Add 200 parts of epoxy resin (Dainippon Ink KKl Oil O50) and 0.2 part of catalyst dimethylbenzylamine, raise the temperature to 180°C again, and keep at 180°C for 1 hour.

After cooling to 150°C, 168 parts of phthalic anhydride, 200 parts of trimethylolethane, 14 parts of trimethylpentanfol
Add 0 parts of maleic anhydride, 48 parts of maleic anhydride, and 53 parts of Sorbin 1maki, and gradually heat to raise the temperature to 180°C VC over 3 hours. The condensation reaction was continued at 180°C until the acid value reached 5.
0. When the donor viscosity of the 60% butyl cellosolve solution of the resin reaches V, the temperature is immediately lowered to 80 ° c-i,
Add about 400 g of isopropyl alcohol, and remove the resin mixture.
i2 shot part 70% solution type: equipped.

143 parts of the Iji 1 fat bath liquid and 21 Sensitized Titanium (Teikoku Kako K)
Mix 100 parts of Inpropyl Al r-/l/s 7 i'rVrk sand mill with 100 parts of K, Jl II 6001 to prepare a mill base of IVV 67, pWc50+.

While stirring a mixture consisting of 107 parts of the resin C, 75 parts of the millbase and 6.5 parts of triethylamine,
Gradually add 811.5 parts of ion-exchanged water to form an aqueous electrodeposition coating dispersion of 1. o o O part is made.

Carving' * G "ti"k 'gQ (7) m jE
4.The electric current LtE was 300'V and the plaftd was 8.4, and the mold was applied on an iron phosphate-treated mild steel plate anode at x50V for 2 minutes and dried at 100°C for 15 minutes to obtain a film thickness of 20.
A smooth hard coating of μ was obtained. The coating film has a scratched pencil hardness) and has a salt water resistance test of 150.
Cellotef'>'r, (l W':!Width was within 31η?n on one side.

Example 2 In a reaction vessel purged with N2, 355 parts of tall oil fatty acid, 54 parts of maleic anhydride, and 59 parts of iron rubic acid are charged and heated to 150°C. After keeping at 150°C for 1 hour, 189 parts of phthalic anhydride, 200 parts of trimethylolethane
Name blocking, IY Kishi) IIIll blindness (Ebikuron 7050
), 40 parts of hydrogenated bisphenol A, and 1,01 parts of nomethylbenolamine were added, and the mixture was gradually heated.
Raise the temperature to 18o ”C over 3 hours. Then 180℃
The acid value is 80, and the resin is 60'I.
) When the Gardner viscosity of the Butylceroserp solution reaches RK, immediately reduce γIi^, add about 300 parts of isopropyl alcohol and about 100 parts of Butylceroserp,
Prepare the resin solution for the resin non-explosion section 70.

Using the above resin solution, millbase was heated in the same manner as in Example 1.
After mixing 107 parts of the above 100% fat solution, 75 parts of the mill base, and 5 parts of TEAIL, 306.5 parts of ion-exchanged water was gradually added to prepare an aqueous electrodeposition coating dispersion.

The pressure of the aqueous dispersion was ILOV and pjl was 7.8.
By curing at 100° C. for 15 minutes, a hard, flat, reversible coating film was obtained.

The coating film has a hard pencil grade H, and the peeling width of the cellophane tape is within 3 and 7 on one side in a 150-hour salt water spray test.

Comparative Example 1 In a reaction vessel purged with N2, 363 parts of linseed oil fatty acid, 371 parts of phthalic anhydride, and 80 parts of trimethylolpropane were added.
and 1.11 parts of Hichentaerys were added and gradually heated to 190°C over 3 hours. 190℃
Ox-1 maintained at: The cross reaction progresses, the acid value is 55, and the Gardner viscosity of the 60% butyl cellosolve solution of the resin is RK.
When this temperature is reached, the temperature is immediately lowered to 80 parts, and about 400 parts of inopropyl alcohol is added to prepare a resin solution containing 70% resin solids.

Prepare a 1g aqueous dispersion of paint in the same manner as in Example 1!
1. Electrodeposition coating and coating film test were performed on the terrarium.

The coating film had a yellow pencil hardness of 4 H or less, and a width of cellophane tape n11-1 after 150 hours of salt water spray resistance test of 8 stops or more on one side.

Comparative Example 2 466 parts of linseed oil fatty acids are heated to 180° C. in a reaction vessel fitted with N2 substitution. Epoxy resin (Epicron 4
050) 95 parts and M medium methylhennolamine 0.1
of the mixture was added, the temperature was raised to 180°C, and the temperature was kept at 180°C for 1 hour. After the temperature was lowered to 150°C, 2321 parts of anhydrous phthalic BH and 218 parts of pentaerythritol were added, and the temperature was gradually heated to 190°C over 3 hours. Ill do it.

The condensation reaction was carried out at 190°C, and the dispersion value was 70,
When the Gardner viscosity of the 60% plastic resin melt reached Ii/V, the temperature was immediately lowered to 80°C (C), about 400 parts of inopropyl alcohol was added by force, and the same molded part of the resin was heated to 1 Learn 14 monthly lessons.

In the same manner as in Example 1, an aqueous electrodeposition paint dispersion was prepared, and electrodeposition was carried out on a plate and a coating film test was performed. The coating film has a Yapre lead IL hardness of F-B, and the cellophane peeling width after 100 hours of salt water spray resistance test is approximately 5111i1 on one side.
Met.

Claims (1)

[Claims] Sorbic acid 1-10 heavy DI% % Maleic anhydride 1-10
Epoxy resin 1 to 30 with a weight of 10 and a molecular weight of 500 or more
Heavy weight, unsaturated fatty acids 20-60 weight, and 1-3
Value of 'rR (e and mono- to tetrahydric alcohol combined 0-
Number average molecular weight obtained by condensing 70% by weight 1.000
~6. OOO1 weight average molecular weight 5,000-200.
000, and a product having an acid value of 25 to 100 is dispersed or dissolved in water using amine or alkali neutralized VC.