JPS60155254A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. for paints, which has excellent pigment dispersion and gives a coating film having excellent weather resistance and gloss retention, consisting of a specified copolymer and an (alkyl-etherified) amino resin. CONSTITUTION:100pts.wt. of the combined quantity of a monomer mixture consisting of 5-50pts.wt. hydrogenated dicyclopentadiene derivative of the formula (wherein R is H, methyl, halogen; R' is a bivalent org. group such as a 1-18C alkylene, etc.; n is 0, 1), 5-30pts.wt. monoethylenically, unsaturated monomer contg. a hydroxyl group, such as 2-hydroxyethyl acrylate, and a copolymerizable unsaturated monomer such as methyl (meth)acrylate is copolymerized in the presence of 0.1-5wt% (based on the total quantity of the monomers) polymn. catalyst such as benzoly peroxide to obtain a copolymer (A). Component A is blended with an amino resin or an alkyl-etherified amino resin (B) obtd. by etherifying the amino resin with an alcohol, in a weight ratio of 95:5-60:40.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermosetting resin composition that provides a coating film with excellent weather resistance and pigment dispersibility.

In recent years, in the paint industry, there has been a demand for paints that have excellent weather resistance (thus requiring no maintenance of the paint film) and are curable at room or low temperatures, from the viewpoint of resource and energy conservation. Conventionally, acrylic resins have been commonly used for applications requiring weather resistance, but there is a desire for further improvement. As for thermosetting resin paints, those containing acrylic resin and amine resin are weather resistant and water resistant.

It is known for its excellent coating properties such as chemical resistance.

However, thermosetting resin paints containing acrylic resins generally have poor compatibility with highly oil-absorbing pigments and have poor pigment dispersibility.

Therefore, in order to improve the pigment dispersibility, a method using an acrylic resin synthesized in the presence of an alkyd resin having unsaturated double bonds has been carried out, but compared to the original performance of acrylic resin, the weather resistance is Poor properties, chemical resistance, etc. Also, fluoroolefins, hydroxyalkyl vinyl ethers.

Copolymers containing alkyl vinyl ether and cyclohexyl vinyl ether as essential components are known, but they have the drawback of poor pigment dispersibility. Also, dicyclopentenyl methacrylate.

The use of copolymers such as dicyclopentenyl acrylate, dicyclopentenoxyethyl methacrylate, and dicyclopentenoxyethyl acrylate is also known, but they have the disadvantage of poor weather resistance.

The present invention is intended to solve these problems, and is to provide a thermosetting resin that has excellent pigment dispersibility (dispersibility of pigments with large oil absorption in %) and further improves the weather resistance of acrylic resins. The composition is provided by Ruru.

That is, the present invention provides (5) general formula (X) (wherein the middle hole of formula 9 is hydrogen, methyl group or ) rogene, R' represents a divalent organic group, and n is 0 or 1) Hydrogenated dicyclopentadiene derivative 5-
50 parts by weight CB) Monoethylenically unsaturated monomer having hydroxyl group 5
A copolymer (1
) as well as amine resins or alkyl etherified resins (II
).

The hydrogenated dicyclopentadiene derivative represented by the general formula (X) as the component (5) of the present invention can be obtained by numbering the dicyclopentenyl group carbon atoms in the compound as shown in the following general formula ([). are combined.

In the general formula (Xl, π is a divalent organic group, and the number of carbon atoms is 1 to 18, preferably 2 to 12. π is preferably an alkylene group or a group represented by -Q'-oiπ''-) Here, R'' and π' are alkylene groups having 2 or more carbon atoms, and π' and π' may be the same or different. m is an integer of 1 or more.

Specifically, tricyclodecyloxy such as tricyclodecyl acrylate, tricyclodecyl methacrylate, tricyclodecyloxyethyl acrylate, tricyclodecyloxyethyl methacrylate, tridizI:1 decyloxyprobyl acrylate, tricyclodecyloxyethyl methacrylate, etc. Examples include alkyl acrylates or methacrylates, acrylic esters or methacrylic esters of polyalkylene glycol tricyclodecyl monoether, such as acrylic esters or methacrylic esters of diethylene glycol tricyclodecyl monoether.

The monoethylenically unsaturated monomer having a hydroxyl group in component (B) includes 2-hydroxyethyl acrylate, 2-hydroxyethyl acrylate,
Examples include hydroxyalkyl acrylates such as -hydroxyalkyl acrylate, hydroxyalkyl methacrylates such as 2-hydroxyethyl methacrylate, and 2-hydroxyalkyl acrylate.

Other copolymerizable monomers of component (C) include methyl acrylate, ethyl acrylate, n-propyl acrylate, and isopropyl acrylate.

n-butyl acrylate, isobutyl acrylate, 2
- Alkyl acrylates such as ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n
-Propyl methacrylate.

Alkyl methacrylates such as isoglobil methacrylate, n-butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, styrene,
Styrenic monomers such as vinyltoluene and α-methylstyrene, vinyl esters of saturated basic acids such as vinyl acetate, vinyl propionate, and vinyl stearate, and unsaturated monomers containing epoxy groups such as glycidyl acrylate and glycidyl methacrylate. , vinyl cyanide such as acryl tetranitrile, methacrylate, and acrylamide.

methacrylamide, N-methylolacrylamide, N
Examples include unsaturated amides such as -butoxymethylacrylamide, α,β-unsaturated dicarboxylic acids such as acrylic acid, methacrylic acid, and maleic acid monoester, and these may be used alone or in combination of two or more.

The above component (3) is used (A1. 5 to 50 parts by weight, preferably 7 to 45 parts by weight, based on 100 parts by weight of the total amount of components (B) and (C). The flexibility of the coating film decreases, and if it is too small, the effect of improving weather resistance by using component (5) will decrease.

The above component (B) is used in an amount of 5 to 30 parts by weight, preferably 7 to 25 parts by weight, based on 100 parts by weight of the total amount of components (A), (B) and (C). If the amount of component (B) is too large, the coating film will not have water resistance, and if it is too small, there will be fewer crosslinking points with the amino resin or alkyl etherified amino resin.

The above component (C) is adjusted and used so that the total amount of components (A), (B), and (C) is 100 parts by weight.

Copolymerization of component (A), component (B) and component (C) is as follows:
If necessary, organic solvents such as toluene, xylene, methyl isobutyl ketone, butyl acetate, cellosolve acetate, n-butanol, etc. are used as a reaction solvent or a diluting solvent. Peroxides such as chabutyl peroxide and azo compounds such as azobisisobutyronitrile and azobisvaleronitrile are preferred.

It is used in an amount of 0.1 to 5% by weight based on the total amount of monomers, and the reaction temperature is about 80 to 130° C. and the reaction time is about 2 to 10 hours.

In the present invention, the amine resin refers to an amine resin obtained by addition-condensation reaction with formaldehyde of amino compounds such as urea, melamine, benzoguanamine, acedoguanamine, etc. alone or in combination with formaldehyde, and an alkyl etherified amine resin. and C. It is obtained by etherifying the amine resin with an alcohol such as methanol, ethanol, gropanol, n-butanol, isobutanol, or the like.

In the present invention, the copolymer (1) and the amine resin or alkyl etherified amino resin (U) are (I)/(It
) is preferably blended in a weight ratio of 9515 to 60/40, particularly preferably 85/15 to 70/30. Outside the above range, the performance of the coating film tends to deteriorate.

The thermosetting resin composition according to the present invention is titanium white.

Inorganic pigments such as cadmium yellow and carbon black,
Inorganic pigments and r that can contain phthalocyanine-based, azo-based organic pigments, and other silicone-based additives.
The amount of the organic pigment used is approximately 9 for the resin solid content of the thermosetting resin composition for paint according to the present invention. 5-20% by weight
, titanium white is 50''-150% by weight, and carbon black is about 1-10% by weight. Pigments and other additives are preferably kneaded with the copolymer before use.

Next, examples related to the present invention will be shown.

Synthesis Examples 1 to 3 and Comparative Synthesis Examples 1 to 3 Using the formulation shown in Table 1 and the polymerization catalyst, 1.5 parts of azobisisobutytetranitrile and 0.5 part of di-t-butyl peroxide were used as follows. A copolymer was produced.

i.e. stirrer, thermometer, reflux condenser.

Into a 10100O flask equipped with a dropping funnel and an inert gas inlet, 50 parts of petroleum mixed solvent Tsurupetz 100 (trade name of Esso Petrochemicals Co., Ltd.) and 10 parts of n-butanol were charged, and the above formulation and polymerization catalyst were added while keeping the temperature at 100°C. A mixed solution was added dropwise over a period of 2 hours, and the mixture was further kept at the same temperature for 1 hour, and then heated to 140°C and reacted for 4 hours to obtain a copolymer. A solvent (Tsurpetz 100) was added to the obtained copolymer to make it about 50 ml. Table 1 shows the solid content, acid value, viscosity, 9-color number, and hydroxyl value of the obtained copolymer solution.

Examples 1 to 3 and Comparative Examples 1 to 1 75 parts (solid content) of the copolymer solutions obtained in Synthesis Examples 1 to 3 and Comparative Synthesis Examples 1 to 3, inbutyl etherified melamine resin (Melamine 289 Hitachi Chemical Co., Ltd. ■Product name) 25 parts (solid content) and leveling agent (Piketol special silicone type m Machining/Pick Mallinckrodt company product name)
0.02 part (solid content) was mixed, and a petroleum-based mixed solvent [equal weight mixture of Tsurupetz 100 and Tsurupetz 150 (both trade names of Esso Petrochemical Co., Ltd.)] was added thereto.

The mixture was diluted with a Ford Cubner 4 to a viscosity of 25 seconds (25° C.) to obtain a thermosetting resin composition.

Table 2 shows the results of the accelerated weathering test of the obtained composition. The test plate was prepared as follows.

Preparation of test plate Primer surfacer was spray coated on a Bonply Donna 144 treated steel plate (100 mm x 300 Peng xo, st), and dried at room temperature for 20 minutes and then at 140°C for 20 minutes.

The film thickness of the primer surfacer was set at 30 to 35 μm. Next, undercoat paint [acrylic resin (Hitaloid 2577T).

Hitachi Chemical ■Product name) 80 parts (solid content) Mela 728 (
Mix 20 parts (solid content) of Hitachi Chemical (trade name) and 5 parts (solid content) of aluminum paste.

Add a solvent (a mixed solvent consisting of 60 parts of xylene, 20 parts of butyl acetate, 10 parts of n-butanol, and 10 parts of cellosolve acetate) and heat in a Ford cup +4 for 18 seconds (2
(adjusted to 0°C)] to a film thickness of 15 to 20 μm, left at room temperature for 2 minutes, and then spray-painted the above thermosetting resin composition to a film thickness of 20 to 25 μm. then at room temperature for 20 minutes, then at 140°C for 20 minutes.
After drying for a few minutes, a coating film was obtained.

Accelerated weathering test method This test plate was tested using a Q-UV accelerated weathering tester (USA).

After exposing the sample for a predetermined period of time under a cycle of ultraviolet irradiation at 50° C. for 4 hours and dew condensation at 50° C. for 4 hours, the 60 degree specular reflectance was measured.

Examples 4 to 6 and Comparative Examples 4 to 6 lti polymer solutions obtained in Synthesis Examples 1 to 3 and Comparative Synthesis Examples 1 to 3, isobutyl etherified melamine resin (Melan 281 Hitachi Chemical ■ trade name) and epoxy resin ( 70 parts, 20 parts, and 10 parts of Epicoat 1001 (trade name of Ciel Chemical Co., Ltd.) are mixed in terms of solid content, and titanium white 50 is mixed with this, and the powder is powdered with a three-roll roll to a particle size of 10 μm using a grain gauge.
A thermosetting resin composition for paints was obtained by kneading the mixture until the mixture was reduced to m or less.

This is a Bonply Donna 144 treated steel plate (150mm
70 mm x O, 8 t) to a film thickness of 30 to 35/Am, and baked at 150° C. for 20 minutes to prepare a test plate and test it. The results are shown in Table 3.

Test method (1) Accelerated weathering test method Same as Example 1 (2) Vertical test Make cuts with a knife at 1 mm intervals on the coating film, and
Make 720,100 pieces so that there are 100 pieces.

A peel test was conducted using cellophane tape. Evaluation,
The number of squares that were not peeled off in the peeling test was recorded in the numerator.

(3) Corrosion Resistance Test After cross-cutting the test plate, expose it to salt water spray for 500 hours and perform a cellophane tape peeling test.

It was conducted according to JIS-Z-2351. Evaluation indicates peeling width.

(4) Chemical resistance A 5% aqueous sulfuric acid solution was spotted on the coating film of the test plate.

After 24 hours, wipe it off and observe the condition of the paint film.

The evaluation was as follows.

◎...No whitening ○...Slight whitening ■...Obvious whitening △...Kana whitening ×...Paint peeling or close to it (5) Stain resistance Tested with red Magic Ben Magic ink was applied on the coating film of the board, and after keeping it warm at 30°C for 24 hours, the state was observed with the naked eye after wiping with butanol.

The evaluation is as follows.

◎...No trace ○...Slight trace■...
There are obvious traces Δ... Significant traces ×... can hardly be wiped away (6) 100 parts of the thermosetting resin composition for paint obtained above and 50 parts of titanium white in place of the above. carbon black 3
After thoroughly mixing 10 parts of the thermosetting resin composition for paint using 10 parts of the mixture, the mixture was spray-painted.

Thereafter, a flow coat was applied on the paint film, and the difference in hue between the non-flow coated area and the flow coated area was observed. The evaluation was ◎...no difference ○...slight difference △...considerably different X...pigment separated.

The thermosetting resin composition for paint according to the present invention has excellent pigment dispersibility, and the coating film thereof has excellent weather resistance (glossy retention).

Claims (1)

[Claims] 1. (A) General formula fX) (However, in formula 1, R is hydrogen, a methyl group, or a halogen, R' represents a divalent organic group, and n is 0 or 1) Hydrogenated dicyclopentadiene derivative 5-5 represented by
0 parts by weight (B) Monoethylenically unsaturated monomer having hydroxyl group 5
Copolymer (I) obtained by blending ~30 parts by weight and (C1 and other copolymerizable unsaturated monomers so that the total is 100 parts by weight) and polymerizing the mixture, and amine resin or alkyl etherified amino A thermosetting resin composition containing resin (n).