JPS59217768A - Method for producing coating resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a test resin composition containing a high molecular weight polyester resin as a main component. More specifically, the polynisdel precondensate (A) obtained by the reaction of dihydric carboxylic acids and/or their alkyl esters with dihydric alcohols contains at least 2
Relating to a method for producing a resin composition for stocks containing as a main component a high molecular weight polyester resin obtained by reacting a polyepoxy compound (B) having epoxy groups and a polycarboxylic anhydride (C). It is something.

It has been known that high-molecular weight saturated polyester made by reacting a 2#i acid such as terephthalic acid or isophthalic acid with a dihydric alcohol can be applied to paints, adhesive inks, etc. Methods for producing high molecular weight polyesters include transesterification, in which lower alkyl esters of dibasic acids such as terephthalic acid and isophthalic acid are transesterified with ethylene glycol, purified, and then polycondensed;
Alternatively, a direct esterification method is used, in which dibasic acids such as terephthalic acid and isophthalic acid are directly esterified with a dihydric alcohol and then polycondensed, but in either method, a degree of vacuum is required in the polycondensation reaction step. However, it had the disadvantage that it required high-vacuum production equipment for industrial use, resulting in expensive polyester. Furthermore, even if this type of high molecular weight linear polyester is used as a baking additive by blending it with a crosslinking agent such as an amine resin or a polyisocyanate compound, it will not contain functional groups at the molecular ends that will react with the crosslinking agent. Because there is only
The drawback was that a coating film with excellent performance could not be obtained. Also, it has poor compatibility with amine resin, which is a crosslinking agent.

Several methods have been proposed to overcome these drawbacks. For example, according to JP-A No. 54-24998, a saturated dibasic acid and glycol are reacted according to known procedures to form an initial condensate, and diincyanate is added to this to increase the molecular weight. A method is proposed. However, although such a method does not require high-vacuum production equipment, it only yields a polyester in which the functional groups that participate in the crosslinking reaction are located at the terminals of the molecule, and are unable to exhibit excellent coating film performance.

According to JP-A-55-155060, an acid component consisting of an aromatic dibasic acid and an aliphatic saturated dibasic acid and an aliphatic saturated glycol having 2 to 10 carbon atoms are combined. Using the usual esterification reaction V (thus, an initial polyester condensate is prepared), an epoxy compound having two epoxy groups in one molecule is added to this, and the amount of epoxy groups relative to the carboxyl groups in the initial polyester condensate is A method has been proposed in which the molecular weight is increased by reacting in a proportion that makes them at least equivalent, and a hydroxyl group as a crosslinkable functional group is generated in the molecule by the reaction between a carboxyl group and an epoxy group. In this method, an equivalent or larger amount of epoxy groups is reacted with the carboxyl groups in the initial polyester condensate, so the acid value of the final resin is inevitably low. Even if a cross-linking agent such as an amino resin is added to the 411 resin binder for paints, which is mainly composed of saturated polyester, the acid value has little effect as an internal catalyst due to the low acid value of the resin. Under these printing conditions, sufficient experience performance cannot be obtained.

In order to compensate for this drawback, external catalysts such as para-toluenesulfonic acid are sometimes used together, but such external catalysts have the disadvantage that their effectiveness gradually decreases during the storage of the raw materials when used in combination with paints. Furthermore, since the resin acid value is low, the compatibility of the amine resin with the curing agent is also poor. On the other hand, if an attempt is made to keep the acid value at a high value, the reaction stops before the reaction between carboxyl groups and epoxy groups has progressed sufficiently, making it impossible to obtain the desired polyester with a sufficiently high molecular weight.

The present inventors have made intensive studies to overcome the above-mentioned drawbacks of conventional methods, and as a result, we have developed a polyester precondensate (A), a polyepoxy compound ( B) and polycarboxylic anhydride (C)
The present invention has completed a method for producing a resin composition for a nuclide, the main component of which is a high molecular weight polyester resin having an appropriate amount of carboxyl groups that exhibits internal acid catalytic effect.

The resin composition for roots produced by the production method of the present invention comprises one or more dicarboxylic acids having no ethylenically unsaturated double bonds and/or their alkyl esters (a
) and one or more dihydric (5) alcohols (bl and (aQb) in a molar ratio of 0.9 to 1
．． A polyester precondensate (A) with an acid value of 3 to 20 obtained by condensation reaction at a ratio of 1.
The main component is a polyester resin with an acid value of 5 to 30 and a cylinder molecular weight that is obtained by reacting a polyepoxy compound (B) having at least two epoxy groups in the molecule and a polycarboxylic anhydride (C). That is. Incidentally, the acid value in the present invention means the acid value in terms of non-volatile content.

Dihydric carbonic acid and/or alkyl ester thereof (
The molar ratio of a) and dihydric alcohol (b) is (butt b+ is in the range of 0.9 to 1.1, and if this value is less than 0.9, the molecular weight of the polyester precondensate [A) is becomes small, and ultimately high molecular weight polyester cannot be obtained.
Conversely, if it exceeds 1.1, there is a drawback that it becomes difficult to control the acid value of the polyester precondensate (A) within the range of 3 to 20.

The acid value of the polyester precondensate CA) is in the range of 3 to 20, and those with an acid value of less than 3 can be reacted with polyevo(6)oxy compound [B] and polycarboxylic anhydride [C'3]. The amount of crosslinkable functional groups generated is insufficient, and excellent performance is not exhibited. In addition, if the acid value exceeds 20f, the molecular weight of the polyester precondensate becomes small, making it unfavorable, and furthermore, the crosslinkable functional group produced by the reaction with the polyepoxy compound CB) and the polyhydric carboxylic anhydride (C). There are too many errors, which is unfavorable in terms of performance balance, especially in terms of visibility.

The polyester precondensate [A] is prepared by combining a dihydric carboxylic acid and/or an alkyl ester thereof) and a dihydric alcohol (b) in an amount of 160 to 260% according to a conventionally known procedure.
It can be easily prepared by carrying out a condensation reaction at a temperature of 0.degree. C. with or without an esterification catalyst.

The ratio of the epoxy equivalent of the polyepoxy compound CB) to 1 carboxyl equivalent of the polyester precondensate [A) is 07 to 1.3 sb, and if it is outside this range, it is not possible to prepare a polyester resin with a high molecular weight. Powerful.

The amount of polycarboxylic anhydride [C] used is such that the acid value of the final high molecular weight polyester resin is in the range of 5 to 3o. For example, when polycarboxylic anhydride (C) is reacted with the reaction product of polyester precondensate (A) and polyepoxy compound CB), polycarboxylic anhydride (C
The equivalent ratio of acid anhydride groups in ) is 1.0 or less with respect to the hydroxyl equivalent of the reaction product, and if it exceeds 1.0, it is unfavorable in terms of performance such as splintability of the a-film.

The acid value of the high molecular weight polyester resin in the present invention is 5 to
If the acid value is less than 5, the effect as an internal acid catalyst is low, and the compatibility with curing agents such as amino resins is also poor. Moreover, when the acid value exceeds 30, the storage stability as a resin composition for roots is significantly inferior.

The divalent carboxylic acids and/or their alkyl esters (a) used in preparing the polyester preassembly (A) include aromatic divalent carboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc. Examples include aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sepamic acid, acid anhydrides thereof, and alkaline esters thereof.

It is preferable to use an aromatic divalent carboxylic acid and an aliphatic divalent carboxylic acid together. The dihydric alcohol (b) includes ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, butanediol, hexanediol, 1,4-cyclohexane dimetatool, bisphenol A or hydrogenated bisphenol A alkyl 1
e-oxide compound, 2.2.4-trimethyl-1,
Examples include 3-bentanediol, hydroxy-2,2-dimethylpropionate, 3-methylpentane-1,5-diol, and one or more of these can be used effectively.

The polyepoxy compound (B) is a compound having at least two epoxy groups in one molecule that are reactive with carboxyl groups. For example, “Epikote 828°1001,
Bisphenol type epoxy compounds such as 1004, 1007" (Shell Chemical Products), 'Ebicuron 800, 1000, 4000" (raw products of Inu Nippon Ink Kagaku (9)),
'Denacol EX-211, EX-321, EX-42
1. Aliphatic ether type epoxy compound such as EX-611'' (Nagase Kasei Kogyo product), 'Yunox 201,
Examples include alicyclic epoxy compounds such as 207'' (Union Carbide Products), ester-type epoxy compounds such as diglycidyl phthalate, and epoxy compounds with a triazine nucleus such as TEPIC (Nippon Kagaku Products).These compounds Among these, bisphenol type epoxy compounds can be used particularly effectively.

Examples of the polycarboxylic anhydride (C) include phthalic anhydride, succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, het's acid anhydride, himic anhydride, trimellitic anhydride, and the like.

The polymeric polyester resin according to the present invention is obtained by reacting a polyester precondensate [A], a polyepoxy compound CB), and a polycarboxylic anhydride (C),
The acid value is in the range of 5 to 30, and the number (10) average molecular weight is in the range of 3.000 to 20.000.

Regarding the reaction method, for example, polyester precondensate (
A), a method of mixing and reacting polyepoxy compound CB) and polycarboxylic anhydride (C)'; after reacting the polyester precombination (A) and the polyepoxy compound (B), the reaction product Polycarboxylic anhydride (
C) Method of adding and reacting; polyester preliminary W, 4
After reacting the additive (A) with the polycarboxylic anhydride (C), the polyepoxy compound (B) is added to the system containing the reaction product.
'Th may be added and reacted, and there are no particular limitations. At this time, the reaction temperature was 100°C to 20°C.
It can be in the range of 0°C. Further, if necessary, Trupetz (hydrocarbon solvent from Esso), xylene, etc. can be used as a reaction solvent. Even if the reaction solvent is not removed from the system after the reaction, it can be used as a part of the resin g drink for the first katsura to be described later.

The standby resin composition according to the present invention is mainly composed of the high molecular weight polyester resin according to the present invention, and optionally contains additives commonly used in this fit composition, such as a flow control agent, a pigment dispersant, etc. can include. Since the polymer 1 polyester resin has a hydroxyl group and/or a spanning carboxyl group as a crosslinkable functional group, it can be used with a crosslinking agent such as an amine resin, a polyisocyanate compound, or a 4-functional poxy compound, if necessary. By incorporating pigments into the material, a wrinkled material with excellent performance can be obtained without using an external acid catalyst.

Hereinafter, the present invention will be explained in more detail with reference to Examples. still,
In the examples, parts refer to parts by weight, and acid values refer to non-volatile content. It also means the number average molecular weight measured by molecular gel permeability chromatography (manufactured by Waterjet Co., Ltd.).

Example 1 In a reactor equipped with a stirrer, a flocculator, and a lagoon, 266 parts of terrental acid, 250 parts of isophthalic acid, 160 parts of sesibanic acid, 124 parts of ethylene glycol, 204 parts of neopentyl glycol, and 4 parts of dibutyltinoxa were added.
10.5 parts and heated to 160℃ under inert gas atmosphere.
The temperature was gradually raised from 10 to 240° C., and a polyester precondensate having an acid value of 15 (hereinafter referred to as polyester-CI) was removed. This polyester (
After dissolving 350 parts of 0.035 parts in 161 parts of "Turupetz 150" (aromatic hydrocarbon solvent manufactured by Esso), 18 parts of "Epicote 828" (bisphenol type epoxy compound manufactured by Shell Chemical), 05 parts of triethylamine and 7 parts of phthalic anhydride. 8 parts were added and reacted at 150° C. for 4 hours to obtain a high molecular weight polyester resin having a molecular weight of about 6000 and an acid value of 102. Next, "Tsurupez 150' and soybean soda rub acetate were added to make the non-volatile content 50.1",
Acid value 10.2. Gardner viscosity 2. A resin composition for v-core was obtained.

Example 2 After dissolving 350 parts of the polyester-(I) of Example 1 in 158 parts of "Tsurupets 150", "Ebicoat 8" was dissolved.
Add 18 parts of 28" and 0.5 parts of triethylamine to 1
React at 50°C for 4 hours to achieve a non-volatile content of 70%.

(13) A reaction product with an acid value of 21 (hereinafter referred to as reaction product-CI). ) was obtained. Antioxidant, product - [:I) 526.5 parts K
7.8 parts of water, 7.8 parts of talic acid, and 3 parts of "Tsurupez 150" were added and reacted at 150°C for 1 hour, resulting in a molecular weight of about 600.
A polymer l'' polyester resin having an acid value of 10.0 was obtained.

Next, "Tsurupez 150" and Kamiguchi I-lube acetate were added to obtain a resin composition HV having a non-volatile content of 49.8"J/value of 10.0 and a Gardner viscosity of 2.

Example 3 Polyester of Example 1 - (I) 35051 (dissolved in 161 parts of "Tsurpetz 150", added 7.8 parts of phthalic anhydride and reacted at 150"C for 1 hour,
18 parts of "Epicote 828" and 0.0 parts of triethylamine.
Add 5 parts and react at 150"C for 4 hours until the molecular weight is 6.
100, a madder molecular weight polyester resin having an acid value of 10.0 was obtained. Next, "Tsurupez 150" and cellosolve acetate were added to obtain a resin composition for Me having a nonvolatile content of 50.3%, an acid value of 10.0, and a Gardner viscosity of Zl+.

(14) Example 4 In the same manner as in Example 1, 166 parts of terephthalic acid, 322 parts of isophthalic acid, 292 parts of adipic acid, 124 parts of ethylene glycol, 312 parts of neopentyl glycol, and 1 part of dibutyltin oxide were reacted. A polyester precondensate having a value of 7 was obtained.

After dissolving the J aso part of this polyester precondensate in 156 parts of "Tsurupez 150", it was dissolved in "Bunacol EX".
-211″ 4.4 parts, “Bunacol EX-421” 1
．． 9 parts (all manufactured by Nagase Chemical Industries, aliphatic ether type epoxy compound), 05 parts of dimethylbenzylamine and 7 parts of trimellitic anhydride were added and reacted at 170°C for 3 hours to obtain a compound with a molecular weight of about 7300 and an acid value of 131. A high molecular weight polyester resin was obtained. Next, "Tsurpetz 150", cellosolve acetate and butyl cellosolve were added to give a non-volatile content of 50.6%, an acid value of 13.1, and a Gardner viscosity of 2. A resin composition for nucleation was obtained.

Torase 1+115 Same method as Example 1 322 parts of terephthalic acid, 322 parts of isophthalic acid, 146 parts of adipic acid, ethyl L/7
/f 124 parts of IJ Cole, 312 parts of neopentyl glycol, and 1 part of dibutyltin oxoid were reacted to obtain a polyester precondensate having an acid value of 10. Add 350 parts of this polyester precondensate to "Tsurupets 1"
After dissolving 167 parts of ``Epicoat 100''
1", 0.5 parts of dimethylbenzylamine, and maleic anhydride were added and reacted at 150°C for 4 hours to obtain a high molecular weight polyester resin with a molecular weight of 6880 and an acid value of 18.0. ″ Add cyclohexanone and methyl isobutyl ketone to reduce the non-volatile content to 4
A resin composition for nucleation was obtained having a concentration of 9.7%, an acid value of 180, and a Gardner viscosity of z4.

Example 498 parts of isophthalic acid, 62 parts of ethylene glycol, 236 parts of 1,6-hexibundiol and 0.5 part of dibutyltin oxide were reacted in the same manner as in Example 1, and the acid value was 1.
A polyester precondensate of No. 6 was obtained. Add 350 parts of this polyester pre-0* condensate to "Tsurupets 150"10
After dissolving in 3 parts, 56 parts of "Epikote 1001",
05 parts of dimethylbenzylamine and 66 parts of succinic anhydride were added and reacted at 150°C for 4 hours, resulting in a molecular weight of about 530.
0, and a high molecular weight polyester resin with an acid value of 6.0 was obtained. Next, xylene and cellosolve acetate were added to obtain a resin composition for nucleation having a nonvolatile content of 49.6%, an acid value of 60, and a Gardner viscosity of Z1.

Example 7 Using the same method as in Example 1, 723 parts of adipic acid, 208 parts of neopentyl glycol, 288 parts of 1,4-cyclohexane dimetatool, 340 parts of hydrogenated bisphenol A with 2 moles of ethylene oxide, and dibutyltin. One part of nuxide was reacted to obtain a polyester preassembly with an acid value of 5. This polyester preliminary (+1if
After dissolving 400 parts of the condensate in 105 parts of "Tsurupez 150", "Bunacol EX-321" 4.7
4 parts and 7.2 parts of maleic anhydride at 180°C.
The reaction was carried out for a period of time to obtain a high molecular weight polyester resin having a molecular weight of 7,500 and an acid value of 11. Next is “Tsurupets 150”
, methyl isobutyl keto (17), and butyl cellosolve were added to make the first JJti for stocks with a nonvolatile content of 49.9%, an acid value of 11.0, and a Gardner viscosity of Z4.
I obtained a paraboloid.

Comparative Example 1 Polyester-III) in Example 1 at lmmHg
The combination reaction proceeded at a vacuum degree of 240℃ and an acid value of 2.
A comparatively high molecular weight polyester of 0 was obtained. Next, "Tsurupez 150°1" and cellosolve acetate were added to obtain a comparative 4/1 fat composition having a non-volatile content of 50, an aqueous acid value of 2.0, and a Gardner viscosity of 2.

Comparative Example 2 The reaction product-[I] in Example 2 was
50'' and Cellosolve Acetitola plus non-volatile content 50
A comparative resin composition for root stocks with an acid value of 21 and a Gardner viscosity of z and - was obtained.

Comparative Example 3 Borienetheru (I) 350H1 in Example 1
After dissolving f in 157 parts of "Tsurupez 150", 18 parts of "Epicoat 828" and 0 parts of triethylamine were added.
．． 5 parts and 1 part of phthalic anhydride were added and reacted at 150"C for 4 hours (18) to obtain a comparatively high molecular weight polyester resin with a molecular weight of about 5900 and an acid value of 2.9. Acetate was added to obtain a comparative coating resin composition having a nonvolatile content of 497%, an acid value of 29, and a Gardner viscosity of zI-.

Comparative Example 4 After dissolving 350 parts of the polyester-(I) in Example 1 in 174 parts of "Tsurupez 150", 18 parts of "Epicoat 828", 05 parts of triethylamine and 38 parts of anhydrous phthalate were added, and the mixture was heated at 150°C. time reaction,
A relatively high molecular weight polyester resin having a molecular weight of about 6,100 and an acid value of 37 was obtained. Next, "Tsurupez 150" and Cellosolve Acedate were added to give a non-volatile content of 503% and an acid value of 3.
7.0, Gardner viscosity 2! - A comparative coating resin composition was obtained.

Comparative Example 5 A polyester preliminary combination having an acid value of 30 was obtained using the same formulation and method as in Example 1. This polyester pre-assembly 350
After dissolving 1 part in 169 parts of "Tsurupets 150"
36 parts of Epikote 828°'', 05 parts of triethylamine and 7.8 parts of phthalic anhydride were added and reacted at 150°C for 6 hours to obtain a relatively high molecular weight polyester resin with a molecular weight of about 5500 and an acid value of 11.2. Next, "Tsurupez 150" and cellosolve acetate were added to obtain a comparative coating resin composition having a nonvolatile content of 495, an acid value of 11.2, and a Gardner viscosity of 2.

Example 8 Each of the coating resin compositions obtained in Examples 1 to 7 and each comparative coating resin composition obtained in Comparative Examples 1 to 5 was treated with melamine resin as a crosslinking agent according to the following procedure. The compatibility was measured. The results were as shown in Table 1.

☆ Compatibility with melamine resin The appearance of the composition when the latter is added to the former until the solid content ratio of the coating resin composition and the melamine resin becomes 5 is observed.

◎: Completely transparent ○: Shows slight fluorescence.

△: Slight turbidity is shown.

×: Cloudy, sometimes separated.

Furthermore, paints were prepared with the following formulations for each of the resin composition for cedar covering and the comparative resin composition for covering, and an ax film was formed using the following coating method, and the film performance was measured. The results were as shown in Table 1.0 ☆Paint formulation:) Coating resin composition/"Super Beckamine L-11"
7” (Melamine resin manufactured by Dainippon Ink Chemical Co., Ltd.) = 55 (solid content weight ratio) 1i) P, W, C, = 50% (Titanium white is used as pigment) +++ ) Painted with thinner (xylene/butyl cellosolve) Diluted to viscosity ☆ Painting method, etc. I) Base material: 03 parts thick “Bonderite + 37” treated galvanized iron plate II) Bar coater painting: Dry film thickness 20 μm 11) Baking conditions = 230°C x 60 seconds (21) (22) ☆ Measurement method: Measure the 60° reflection gloss value using a gloss meter.

Adhesion: 111+1TI x 1m with a cutter to the coating film
Cut out the m gongs and perform a peel test with cellophane tape.

Addition 1: Strength: 180° bending test with vise ◎: Excellent, ○
: Good, △: Tsukasa, ×: Impossible Impact resistance: Measured using a Devon impact tester.

O: Excellent, ○: *, △: Fair, ×: Impossible Stain resistance: 9 rare, 24 when rubbing magic ink on the paint film
After leaving it for a while, wash it off with ethanol and determine the state of the paint film's contamination.

◎: Excellent, ○: Good, △: Fair, X: Poor Xylene resistance: The coating surface is rubbed with gauze impregnated with xylene, and the state of destruction of the coating film is observed.

・: Excellent, ○: Good, △: Fair, ×: Not possible (23) 483-

Claims (1)

[Claims] One or more dihydric carboxylic acids and/or their alkyl esters having no ethylenically unsaturated double bonds (a) and 1eit or 2m or more of 2x1 alcohol (bl) and (a i b ) with an acid value of 3 to 20 obtained by condensation reaction at a molar ratio of 0.9 to 1.1, containing at least two epoxy groups in one molecule. A method for producing a resin condensate for coating, the main component of which is a high molecular weight polyester resin with an acid value of 5 to 30 obtained by reacting a polyepoxy compound (B) and a polycarboxylic anhydride (C).