JPH0623222B2 - Air-drying unsaturated polyester resin composition - Google Patents

Description

The present invention relates to an air-drying unsaturated polyester resin composition,
In particular, the present invention relates to an air-drying unsaturated polyester resin composition having excellent air-drying property, high durability, high hardness, high glossiness and high durability.

(Prior Art) An unsaturated polyester resin composition having an allyl group has been conventionally known as an air-drying imparting agent, and there is no inhibition of curing by air. Therefore, general woodworking coating is used instead of the wax-type unsaturated polyester resin composition. , Car repair putty and UV
It is used for a wide range of applications such as high-grade floorboard coating by curing.

However, this unsaturated polyester resin composition containing an allyl group is not satisfactory for all uses, and when it is used as a coating film for musical instruments such as pianos, electric tones and organs, (1) wax Since the residual rate of the coating film after curing is lower than that of the type paint, a high-quality finish cannot be obtained. (2) The coating surface becomes white and wavy due to frictional heat during buffing. (3) When buffing is performed. If the coating film is hardened in order to prevent the whitening, there is a defect that cracking occurs in the cold heat test.

In the coating film of musical instruments, a high-grade feeling is required, and durability is required under severe conditions, that is, high durability to maintain a high-grade feeling, buff burning in the painting process, and It is necessary to prevent scratches and have a high degree of durability so that cracking does not occur even under extremely cold conditions.

(Problems to be Solved by the Invention) An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to have excellent air-drying property, high durability, high hardness, high gloss and high durability. Another object of the present invention is to provide an air-drying unsaturated polyester resin composition suitable for coating.

(Means for Solving Problems) As a result of intensive studies by the present inventors, the above object can be achieved by limiting the composition of the air-drying unsaturated polyester resin composition. The present invention has been accomplished by finding that high-quality finish, good workability such as grinding and buffing, and tough coating properties can be obtained.

The present invention relates to an unsaturated polyester resin having an allyl group.
In an air-drying unsaturated polyester resin composition containing (A) and a polymerizable monomer (B), (1) (A) is a viscosity when diluted with styrene to a heating residue of 75% (Gardner, 25 ° C. ) Is 4 to 30 poise, and the content of allyl glycidyl ether as an allyl group-containing component of (2) (A) is 5 to 30% by weight in the resin as the amount of condensed water removed. As the polybasic acid component, an acid anhydride of the same mole or more as that of the above allyl glycidyl ether is used, and the unsaturated polybasic acid is 80 mol% or more in the total polybasic acid component, and the polybasic acid of (4) (A) is used. As a polyhydric alcohol component, 8 polyhydric alcohols having no ether bond are used.
Use 0 mol% or more, and (1) add (5) polymerizable monomer (B) to 1
The present invention relates to an air-drying unsaturated polyester resin composition containing 0 to 60% by weight.

The unsaturated polyester resin (A) having an allyl group used in the unsaturated polyester resin composition of the present invention comprises an allyl glycidyl ether and an acid anhydride in the same mole or more as the ring-opening catalyst and a part of the polyhydric alcohol. Or, in the presence of the whole amount, it is heated at 40 to 140 ° C. for 20 minutes to 3 hours, after completion of the ring-opening reaction of allyl glycidyl ether, the remaining polyhydric alcohol and polybasic acid are further added, and at 150 to 220 ° C. Obtained by condensation for 20 hours.

The viscosity (Gardner, 25 ° C.) of this unsaturated polyester resin (A) when diluted with styrene to a heating residue of 75% imparts curability and high-thickness characteristics sufficient to obtain sufficient coating strength. Therefore, it is set to 4 to 30 poises, preferably 6 to 25 poises. When the viscosity is less than 4 poise, the curing rate is slow because the molecular weight is small, and a tough coating cannot be obtained. When it exceeds 30 poise, a large amount of polymerizability is required to obtain an appropriate coating viscosity. A monomer is required, and the durability of the coating film after curing is reduced, and a high-quality finish feeling cannot be obtained.

The unsaturated polyester resin (A) has an allyl glycidyl ether as an allyl group-containing component in an amount of 5 to 30% by weight, preferably 6 to 25% by weight as the amount of condensed water removed from the resin.
contains.

In the present invention, focusing on the reactivity of the epoxy group of allyl glycidyl ether, and from the relationship between the type of allyl group-containing component and the buffing aptitude that is absolutely necessary for piano coating,
Allyl glycidyl ether is used as the allyl group-containing component.

That is, when the trimethylolpropane diallyl ether, glycerin gin aryl ether or glycerin monoallyl ether was used as the polyhydric alcohol allyl ether, and when the allyl glycidyl ether used in the present invention was used, the allyl group content, Keep the type and molar ratio of basic acid and polyhydric alcohol constant,
The viscosity when diluted to 75% with styrene (Gardner,
At 25 ° C.), a cured coating film of a composition adjusted to 15 to 17 poise was observed for the coating surface state after buffing (buff burning, smoothness). As a result, the coating surface state was trimethylolpropane diallyl ether. (Whitening wavy due to buff burning), glycerin diallyl ether, glycerin monoallyl ether, and allyl glycidyl ether (smooth without buff burning) were good in this order. This is allyl glycidyl ether It has an epoxy group in the molecule as shown in Fig. 3 and is highly reactive, so the unreacted allyl glycidyl ether in the resin is small, or the molecular chain of the allyl group component is higher than that of polyhydric alcohol allyl ether. Since it is small, it is presumed that deterioration due to frictional heat during buffing is small.

The amount of allyl glycidyl ether of unsaturated polyester resin (A) (the amount after removing the condensation water) is 5 to 30% by weight, preferably 6 to 25% by weight. If this amount is less than 5% by weight, sufficient air-drying property cannot be obtained, drying is slow, and grinding workability for removing dust and the like adhering to the cured coating (water-resistant paper, according to # 600 to 800). (Grinding) significantly decreases, and when it exceeds 30% by weight, the unsaturated group concentration of the resin decreases and the curability decreases, so a high hardness coating cannot be obtained and the coating after buffing has a wavy shape. Becoming a phenomenon.

Examples of the allyl glycidyl ether used in the present invention include Epiol A (trade name) manufactured by NOF CORPORATION, Neoallyl G (trade name) manufactured by Osaka Soda Co., Ltd., and the like.

The unsaturated polyester resin (A) uses, as a polybasic acid component, an acid anhydride of the same mole or more as the above allyl glycidyl ether, and contains 8 or more unsaturated polybasic acids in all polybasic acid components.
It is used in an amount of 0 mol% or more.

The acid anhydride in the same mole or more as the allyl glycidyl ether is used so that the ring-opening reaction of the epoxy group of the allyl glycidyl ether is sufficiently performed.

The ring-opening reaction of the epoxy group is carried out, for example, by using a quaternary ammonium salt (eg, tetraammonium chloride, dimethyldodecylbenzylammonium chloride, etc.) or an alkali metal salt (eg, potassium benzoate, etc.) as a ring-opening catalyst.
(Sodium benzoate, etc.) is used in an amount of 0.05 to 5.0% by weight based on allyl glycidyl ether, and 40 to 140% in the presence of some or all of the polyhydric alcohol in order to prevent heat generation that occurs when the epoxy group is opened. It is carried out by heating at 0 ° C. for 20 minutes to 3 hours.

As described above, the unsaturated polybasic acid is used in an amount of 80 mol% or more in the total polybasic acid component of the unsaturated polyester resin (A). When it is less than 80 mol%, a black colorant (for example, carbon In a paint system using black, aniline black, etc.), the curability is lowered and the workability of the coating is significantly impaired. In addition, the coating film is messy, and a high-quality finish cannot be obtained.

Examples of the polybasic acid component used in the present invention include unsaturated polybasic acids such as maleic anhydride, maleic acid, itaconic anhydride, itaconic acid and fumaric acid, phthalic anhydride, tetrahydrophthalic anhydride and 3-methyl. -Saturated polybasic acids such as tetrahydrophthalic anhydride, hymic acid, trimellitic acid, isophthalic acid, terephthalic acid, adipic acid and sebacic acid. These polybasic acids may be one type or two types.
Used as a mixture of two or more species.

For the unsaturated polyester resin (A), 80 mol% or more of polyhydric alcohol having no ether bond is used as the polyhydric alcohol component.

In order to investigate the relationship between the type of polyhydric alcohol component and the buffing aptitude, the present inventors have developed a resin composition obtained by using a polyhydric alcohol having an ether bond, such as diethylene glycol or dipropylene glycol, with an ether bond. A comparative observation was carried out with a resin composition comprising propylene glycol, ethylene glycol, neopentyl glycol, etc., which are polyhydric alcohols that do not have them. As a result, the former resin composition had whitening and wavy phenomena in the coating film after 100% buffing, whereas the latter resin composition did not have these phenomena. It is presumed that this is because the ether bond portion in the resin composition has some deterioration phenomenon due to frictional heat and dynamic action during buffing on the surface of the coating film.

In order to prevent these whitening and wavy phenomena and obtain a practical coating film, the unsaturated polyester resin is used in the present invention.
As the polyhydric alcohol component (A), a polyhydric alcohol having no ether bond is used in an amount of 80 mol% or more. When it is less than 80 mol%, the above-mentioned whitening and wavy phenomenon occur,
A high-quality coating cannot be obtained.

Examples of the polyhydric alcohol having no ether bond used in the present invention include ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, hydrogenated bisphenol A, glycerin and penta. Examples thereof include erythritol, trimethylolpropane, trimethylolethane and the like. These polyhydric alcohols are used alone or in combination of two or more.

Examples of the polyhydric alcohol having an ether bond include diethylene glycol, dipropylene glycol,
Triethylene glycol or the like is used.

The unsaturated polyester resin composition of the present invention contains the polymerizable monomer (B) in an amount of 10 to 60% by weight, preferably 15 to 50% by weight.

When the content of the polymerizable monomer (B) is less than 10% by weight, the reaction with the unsaturated polyester resin (A) is insufficient and a coating film with high hardness cannot be obtained, and the content is 60% by weight. When it exceeds the above range, the durability is deteriorated, a high-quality coating film cannot be obtained, and the curability tends to decrease.

Examples of the polymerizable monomer (B) used in the present invention include styrene, vinyltoluene, α-methylstyrene, divinylbenzene, t-butylstyrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester,
Methylene bis acrylamide, glycidyl methacrylate, 2-hydroxy methacrylate, etc. may be mentioned.

The air-drying unsaturated polyester resin composition of the present invention comprises the above-mentioned unsaturated polyester resin (A) having an allyl group and the above-mentioned polymerizable monomer (B) It is obtained by blending so that the content is 10 to 60% by weight.

The curing catalyst used for curing this composition is
Combination of radical polymerization initiator with metallic soap, amine, amine salt, etc., such as methyl ethyl ketone peroxide, benzoyl peroxide, cyclohexanone peroxide, t-butyl peroxide, etc., cobalt octenoate, manganese naphthenate, copper naphthenate ，
A combination with dimethylaniline, diethylaniline, dimethylacetoacetamide and the like is preferable.

If desired, the unsaturated polyester resin composition of the present invention contains a filler, a pigment, a coloring agent, a leveling agent, an anti-sagging agent,
An abrasive or the like can be added.

Fillers and pigments include calcium carbonate, kaolin, clay, alumina, talc, lithopone, and mica. Colorants include red iron oxide, aniline black, titanium white, cyanine blue, iron black, black yellow, carbon black, and the like. , As the leveling agent, silicone,
Cellulose acetate butyrate, various surfactants, etc. are used, anti-sagging agents are silicon dioxide, etc., and abrasives are fine talc, zinc stearate, etc.

(Effect of the Invention) The air-drying unsaturated polyester resin composition of the present invention is excellent in air-drying property, and has high durability, high hardness, high gloss and high durability. The resin composition of the present invention comprises a piano, an organ,
Not only is it suitable for painting musical instruments such as Electone, but it can also be applied for general woodworking and as a UV-curable paint in combination with a photosensitizer, and its practical effects are remarkable. .

(Examples) Hereinafter, the present invention will be specifically described with reference to Examples. Parts and% in the following examples mean parts by weight and% by weight.

Comparative Example 1 In a two flask equipped with a stirrer, a gas introduction tube, a reflux condenser and a thermometer, 443 parts (4.52 mol) of maleic anhydride, 107 parts (0.723 mol) of phthalic anhydride and 380 parts (5.0 mol of propylene glycol). ), 20 parts of xylene and 0.2 part of hydroquinone were added, and the mixture was reacted at 150 to 180 ° C. while blowing nitrogen gas until the acid value reached 98 (KOHmg / g). Then, the mixture was cooled to 120 ° C., 200 parts (0.935 mol) of trimethylolpropane diallyl ether was added, the temperature was raised to 180 ° C. again, and the esterification reaction proceeded while measuring the viscosity of the contents in the kettle at the same temperature. Regarding the viscosity, 75 parts of the content was dissolved in 25 parts of styrene, and the Gardner viscosity was determined at 25 ° C. with the remaining heating of 75%. When the viscosity reaches 5.8 poise, cool to 160 ° C and measure the viscosity of the contents in the kettle in the same manner as above while depressurizing (1 mmHg) to remove xylene in the system, and finish when the viscosity is 11.2 poise. And The removed condensed water was 85.2 parts. (0% by weight of allyl glycidyl ether, 86.2 unsaturated polybasic acid
Mol%, 100 polyhydric alcohol having no ether bond
Mol%) Styrene was added to the obtained resin so that the heating residue became 75%, and the acid value was 18.5 and the viscosity was 13.6 poise (Gardner, 25 ° C).
To obtain a pale yellow transparent resin composition.

Comparative Example 2 213 parts (1.868 mol) of Epiol A (allyl glycidyl ether manufactured by NOF CORPORATION), 96 parts (0.649 mol) of phthalic anhydride, and 150 parts (1.5 parts of maleic anhydride) were placed in a 2 flask.
31 mol), 1.0 part of dimethyldodecylbenzylammonium chloride (manufactured by NOF CORPORATION), 0.2 part of hydroquinone and 163 parts of propylene glycol (2.145 mol), and while blowing nitrogen gas, pay attention to heat generation and keep the temperature at 80 ° C.
The temperature was raised to. After heating at the same temperature for 1 hour, the temperature was raised to 120 ° C. to further promote the reaction, and after heating at the same temperature for 2 hours, it was cooled. Next, the amount of residual Epiol A (allyl glycidyl ether) in the contents of the kettle was measured by gas chromatography, and as a result, only traces remained.

Further, 251 parts (2.561 mol) of maleic anhydride, 227 parts (2.142 mol) of diethylene glycol and 20 parts of xylene were added, the temperature was raised to 180 ° C. again, and the condensation reaction was carried out in the same manner as in Comparative Example 1 after adding trimethylolpropane diallyl ether. Was done. The viscosity was measured in the same manner as in Comparative Example 1, and when the viscosity reached 4.9 poise, it was cooled to 160 ° C,
Similarly, the viscosity was measured under reduced pressure (1 mmHg), and the time when the viscosity was 12.8 poise was regarded as the end. The condensed water removed is
It was 70.2 copies. (Content of allyl glycidyl ether
20.7% by weight, unsaturated polybasic acid 86.3 mol%, polyhydric alcohol without ether bond 50.0 mol%) Add styrene to the obtained resin so that the heating residue becomes 75%, acid value 20.1, viscosity 14.2 Poise (Gardner, 25
C.) yellowish transparent resin composition was obtained.

Comparative Example 3 213 parts of Epiol A (1.868 mol), 399 parts of phthalic anhydride (2.696 mol), 1.0 part of dimethyldodecylbenzylammonium chloride, 0.2 part of hydroquinone and 178 parts of propylene glycol (2.342 mol) were placed in a two-flask. The ring-opening reaction of Epiol A was terminated in the same manner as in 2.

Further, 264 parts (2.694 mol) of maleic anhydride, 177 parts (2.329 mol) of propylene glycol and 20 parts of xylene were added and the condensation reaction was carried out in the same manner as in Comparative Example 1. The viscosity was measured in the same manner as in Comparative Example 1, and when the viscosity reached 7.0 poise, it was cooled to 160 ° C., and the viscosity was measured similarly under reduced pressure (1 mmHg), and the point when the viscosity was 13.6 poise was ended. . The removed condensed water was 70.2 parts.
(Content of allyl glycidyl ether 18.4% by weight, unsaturated polybasic acid 50.0% by mole, polyhydric alcohol without ether bond 100% by mole) Styrene was added to the obtained resin so that the remaining heating was 75%. Acid value 14.8, viscosity 12.6 poise (Gardner, 25
A transparent resin composition having a yellowish (.degree. C.) was obtained.

Comparative Example 4 In a two flask, 450 parts of Epiol A (3.947 mol), 118 parts of phthalic anhydride (0.797 mol), 320 parts of maleic anhydride (3.265 mol), 2.0 parts of dimethyldodecylbenzylammonium chloride, 0.2 parts of hydroquinone.
Parts and 100 parts of propylene glycol (1.316 mol)
Was added to complete the ring-opening reaction of Epiol A in the same manner as in Comparative Example 2. Furthermore, 151 parts of maleic anhydride (1.54
1 mol) and 26 parts (0.342 mol) of propylene glycol were added and a condensation reaction was carried out in the same manner as in Comparative Example 1. The viscosity was measured in the same manner as in Comparative Example 1, and when the viscosity reached 4.2 poise, it was cooled to 160 ° C. and the viscosity was measured in the same manner while reducing the pressure (1 mmHg). . The removed condensed water was 30.3 parts. (Content of allyl glycidyl ether 39.7% by weight, unsaturated polybasic acid 85.8% by mole, polyhydric alcohol without ether bond 100% by mole) Styrene was added to the obtained resin so that the heating residue would be 75%. Acid value 3.5, viscosity 6.1 poise (Gardner, 25 ℃)
To obtain a deep yellowish transparent resin composition.

Example 1 In a 2 flask, 213 parts (1.868 mol) of Epiol A, 110 parts (0.743 mol) of phthalic anhydride, 150 parts (1.531 mol) of maleic anhydride, 1.0 part of dimethyldodecylbenzylammonium chloride, 0.2 parts of hydroquinone.
Parts and 178 parts of propylene glycol (2.342 mol)
Was added to complete the ring-opening reaction of Epiol A in the same manner as in Comparative Example 2.

Further, 305 parts (3.112 mol) of maleic anhydride, 177 parts (2.329 mol) of propylene glycol and 20 parts of xylene were added and the condensation reaction was carried out in the same manner as in Comparative Example 2. The viscosity was measured in the same manner as in Comparative Example 1, and when the viscosity reached 6.8 poise, it was cooled to 160 ° C and the viscosity of the contents in the kettle was measured in the same manner while reducing the pressure (1 mmHg).
3.2 The time for poise has ended. Condensed water removed is 71.9
I was in the department. (Allyl glycidyl ether content 20.1
% By weight, unsaturated polybasic acid amount 86.2 mol%, polyhydric alcohol amount without ether bond 100 mol%) Styrene was added to the obtained resin so that the heating residue became 75%, acid value 17.8, viscosity 14.8 Poise (Gardner, 25
C.) yellowish transparent resin composition was obtained.

Example 2 In a two-flask, 213 parts of Epiol A (1.868 mol), 110 parts of phthalic anhydride (0.743 mol%), 228 parts of maleic anhydride (2.327 mol), 1.0 part of dimethyldodecylbenzylammonium chloride, hydroquinone.
0.2 parts and 178 parts (2.342 mol) of propylene glycol were added, and the ring-opening reaction of Epiol A was terminated in the same manner as in Comparative Example 2.

Further, 269 parts (2.319 mol) of fumaric acid, 177 parts (2.329 mol) of propylene glycol and 20 parts of xylene.
Then, a condensation reaction was carried out in the same manner as in Comparative Example 2.
The viscosity was measured in the same manner as in Comparative Example 1, and when the viscosity reached 7.2 poise, it was cooled to 160 ° C, and the viscosity of the contents in the kettle was similarly measured while reducing the pressure (1 mmHg). The time point was ended. The removed condensed water was 97 parts. (The content of allyl glycidyl ether is 19.8% by weight, the amount of unsaturated polybasic acid is 86.2 mol%, and the amount of polyhydric alcohol having no ether bond is 100 mol%.) Add acid value 20.6, viscosity 15.9 poise (Gardner, 25
C.) yellowish transparent resin composition was obtained.

Example 3 In a two flask, 213 parts of Epiol A (1.868 mol), 112 parts of tetrahydrophthalic anhydride (0.737 mol), 150 parts of maleic anhydride (1.531 mol), 1.0 part of dimethyldodecylbenzylammonium chloride, 0.2 part of hydroquinone and propylene glycol. 178
Part (2.342 mol) was added and the ring-opening reaction of Epiol A was terminated in the same manner as in Comparative Example 2.

Further, 257 parts (2.622 mol) of maleic anhydride, 177 parts (2.329 mol) of propylene glycol and 20 parts of xylene were added, and a condensation reaction was carried out in the same manner as in Comparative Example 2. The viscosity was measured in the same manner as in Comparative Example 1, and the viscosity was 4.8.
When it becomes a poise, it is cooled to 160 ℃ and decompressed (1 mmHg)
While measuring the viscosity of the contents in the pot in the same way,
11.3 The time of the poise was ended. Condensed water removed is 7
It was 0.8 copies. (Content of allyl glycidyl ether 2
1.0 wt%, unsaturated polybasic acid amount 85 mol%, polyhydric alcohol amount without ether bond 100 mol%) Styrene was added to the obtained resin so that the heating residue became 75%, and the acid value was 16.8, Viscosity 12.2 Poise (Gardner, 25
C.) yellowish transparent resin composition was obtained.

Test Example (Coating Performance of Resin Composition) The coating performance of the resin compositions obtained in Comparative Examples 1 to 3 and Examples 1 to 3 was tested as follows.

(1) Coating composition and preparation 50 parts of the resin composition, 3 parts of Carbon Black MA-100 (manufactured by Mitsubishi Kasei Co., Ltd.), and 0.2 parts of Erosil 200 (manufactured by Nippon Irosil Co., Ltd.) were kneaded three times with a three-roll mill. 50 parts of resin composition, 20 parts of styrene, 2 parts of 1% toluene solution of Bayer Silicon PL (manufactured by Bayer), 6 parts of this roll kneaded product
% Cobalt octenoate (manufactured by Dainippon Ink and Chemicals, Inc.) 1.5 was uniformly dispersed, and then a coating material was prepared in which styrene cut product # 4 had a viscosity (25 ° C.) of 55 to 70 seconds.

(2) Preparation of test plate 55% methyl ethyl ketone peroxide 1.5% was added to the coating material obtained in (1), and it was dispersed evenly to give a film thickness of 450-500μ on a wood plywood plate (10 cm x 20 cm). A test plate was prepared by applying a spray gun as described above, drying at 25 ° C. for 24 hours, and then curing at 60 ° C. for 1 hour. Using this test plate, the following tests (3) and below were performed.

(3) Coating film performance results The following coating film performances were tested for the resin compositions of Comparative Examples and Examples, and the results are shown in Table 1.

1) Curability: The time until the coating gels after the addition of 55% methyl ethyl ketone peroxide 1.5% to the coating obtained in (1) (25 ° C).

2) Air-drying: The time until the fingerprints are no longer left after pressing the surface of the coated plywood with a finger strongly after spray coating (25
C).

3) Coating residual rate: 4) Meatability: The finish of the coating film was visually observed.

 ⊚: A feeling of high flesh is exhibited, and the base grain does not appear on the painted surface.

 ◯: The feeling of flesh is slightly inferior, but the base grain does not appear on the painted surface.

 Δ: The surface of the plywood plywood is exposed on the coated surface.

5) Grindability: The grindability was shown when the coated surface was polished with water resistant paper # 600.

 ⊚: Can be ground well with light polishing.

 ◯: Grinding requires a little force.

Δ: There is entanglement in the paper, and grinding is somewhat difficult.

6) Suitability for buffing: The coating film surface was buffed for 2 minutes with a high-speed sander covered with a waste, and the finished state was visually observed.

 Whitening of coating film: The coated surface is whitened and blurred.

 Smoothness: Presence or absence of coated surface.

7) Gloss: 6) buff-polished test plate for 2 minutes Suga Test Instruments Co., Ltd. gloss measuring instrument model UGV-50 (light receiving angle 60
) Was used for the measurement.

8) Pencil hardness: Hardness with which a Mitsubishi Uni-Pencil is used and hard pressed at an angle of 45 ° on the coated surface until no scratch marks remain.

9) Heat cycle property: The coated plate was left in a freezer at -20 ° C for 1 hour, and then immediately put in a constant temperature dryer at + 60 ° C and left for 1 hour. This state was repeated and the number of times until cracks occurred on the coated surface was examined.

The results in Table 1 show that the resin composition according to the present invention is excellent in air-drying property, and has high wall thickness, high hardness and high durability.

Claims (1)

[Claims] 1. An unsaturated polyester resin having an allyl group.
In an air-drying unsaturated polyester resin composition containing (A) and a polymerizable monomer (B), (1) (A) is a viscosity when diluted with styrene to a heating residue of 75% (Gardner, 25 ° C. ) Is 4 to 30 poises, and (2) 5 to 30% by weight of allyl glycidyl ether as an allyl group-containing component in the resin is contained in the resin as an allyl group-containing component of (3) (A). As the polybasic acid component, an acid anhydride of the same mole or more as the allyl glycidyl ether is used, and the unsaturated polybasic acid is 80 mol% or more in all the polybasic acid components, and the polybasic acid of (4) or (A) is used. An air-drying unsaturated polyester resin composition containing 80 mol% or more of a polyhydric alcohol having no ether bond as a polyhydric alcohol component and (5) containing 10 to 60% by weight of a polymerizable monomer (B). .