JP2001278966A - Method for producing polyester resin and resin composition for coating material using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing a polyester that is less forming in the polymerization and less lot dispersion on the dry coating film. SOLUTION: In the method for producing a polyester resin (B) that consists of the aromatic dicarbonic acid of 50-100 mol% as the acid component, the aliphatic and/or alicycic dicarbonic acid of 0-50 mol%, the alkylene oxide adduct of the bisphenol (A) and/or bispheol (B) shown by formula (1) as the glycol component and the polyol of 0-95%, the method for producing the polyester resin is characterized by applying the alkylene oxide adduct of the isopropenyl phenol and/or the alkylene oxide adduct (A) of the bisphenol A and/or bisphenol (B) that the content of the alkylene oxide adduct of the vinylphenol is below 20,000 ppm, as a row material. [In the formula, R1, R2 or R3 is hydrogen or methyl group, while m or n is one or more integer, respectively, it is 2<=m+n<=8].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a polyester resin. The production of polyester resins, especially high molecular weight polyester resins having a number average molecular weight of 2,000 or more, is usually carried out by a three-can method of esterification, initial polymerization, late polymerization, or a two-can method in which this polymerization step is performed in one stage. . At this time, when foaming occurs during esterification, transesterification, and polymerization under reduced pressure, a significant problem arises because the resin and raw materials during polymerization overflow from the reaction vessel. In addition, the quality of the obtained polyester resin must be stable for each lot.

[0002]

2. Description of the Related Art Polyester resins using an alkylene oxide adduct of bisphenol A and / or bisphenol F as a raw material, mainly for coating resins, are known. For example, as a coating resin, Japanese Patent Publication No. Sho 62-54
No. 67, Japanese Unexamined Patent Publication No. 3-217471, and the like are known.

[0003]

However, when producing a polyester resin using such an alkylene oxide adduct of bisphenol A and / or bisphenol F as a raw material, it is difficult to produce a polystyrene resin using a conventional monomer system represented by polyethylene terephthalate. Not possible, during esterification,
At the time of transesterification, foaming may occur remarkably regardless of the time of polymerization under reduced pressure, which is a major problem. The polyester resin produced by the production method of the present invention is useful as a coating resin or a coating agent, and is particularly suitable as a resin for a primer coating of a metal plate or an image recording medium such as a thermal sublimation transfer type image receiving paper. Although used, those manufactured by the conventional method have problems in that, in addition to the foaming problem at the time of the manufacturing described above, the physical properties of the coating film are insufficient and the dispersion is large.
For example, there is a problem that corrosion resistance, poor appearance after a boiling water test, and fingerprint resistance vary, and recent severe demand for physical properties of a coating film is insufficient in corrosion resistance, pressure mark resistance, and the like.

[0004]

The causes of these problems have been unknown for many years, but as a result of intensive studies by the present inventors, they are contained as trace impurities in the alkylene oxide adduct of bisphenol A and / or bisphenol F. The inventors have found that an alkylene oxide adduct of isopropenyl phenol or vinyl phenol affects foaming during polymerization and physical properties of a coating film, and has reached the present invention.

That is, according to the present invention, the acid component is an aromatic dicarboxylic acid of 50 to 100 mol%, the aliphatic and / or alicyclic dicarboxylic acid is 0 to 50 mol%, and a bisphenol represented by the general formula (1) as a glycol component: The alkylene oxide adduct of A and / or bisphenol F is 5 to
In the method for producing a polyester resin (B) comprising 100 mol% and other polyols of 0 to 95 mol%, the content of an alkylene oxide adduct of isopropenylphenol and / or an alkylene oxide adduct of vinylphenol as a raw material is reduced. A method for producing a polyester resin, comprising using an alkylene oxide adduct (A) of bisphenol A and / or bisphenol F at 20,000 ppm or less.

Embedded image (Wherein R ₁ , R ₂ and R ₃ are hydrogen or a methyl group;
m and n are each 1 or more, and at the same time, 2 ≦ m + n
≦ 8. )

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing a polyester resin of the present invention is applied when the glycol component contains bisphenol A and / or bisphenol F alkylene oxide adduct (A) in an amount of 5 to 100 mol%.

The alkylene oxide adduct (A) of bisphenol A and / or bisphenol F is prepared by adding an alkylene oxide to bisphenol A and / or F in the presence of an alkali catalyst and then neutralizing with an acid. At this time, it was found that bisphenol A or bisphenol F as a raw material was thermally decomposed to generate a small amount of isopropenyl phenol or vinyl phenol, to which alkylene oxide was added. Furthermore, it has been found that when these impurities remain in a certain amount or more, they foam during polyester production or adversely affect the physical properties of the coating film. The present inventors have also confirmed that the higher the reaction temperature at the time of adding an alkylene oxide, the more these impurities are generated.

The content of the alkylene oxide adduct of isopropenylphenol and / or the alkylene oxide adduct of vinylphenol is 20,000 ppm or less based on the amount of the alkylene oxide adduct of bisphenol A and / or bisphenol F used. And more preferably 10,000
ppm, more preferably 8,000 ppm or less, and most preferably 5,000 ppm or less. When the content of these by-products exceeds 20,000 ppm, foaming occurs at the time of polymerization, and the physical properties of the coating film described above deteriorate.

The alkylene oxide adduct of bisphenol A and / or bisphenol F (A) used in the polyester resin production method of the present invention is 5 to 100 mol%, preferably 1 to 100 mol%, based on all glycol components.
The content is 5 to 80 mol%, more preferably 25 to 60 mol%. If it is less than 5 mol%, the excellent properties of the glycol (A) such as corrosion resistance and workability cannot be obtained.

In the method for producing a polyester resin of the present invention, the acid component used in the produced polyester resin (B) is an aromatic dicarboxylic acid of 50 to 100 mol%, preferably 70 to 100 mol%, more preferably 80 to 100 mol%. 10
0 mol%. If the amount of the aromatic dicarboxylic acid is less than 50 mol%, good acid resistance, chemical resistance, corrosion resistance and scratch resistance cannot be obtained.

Examples of the aromatic dicarboxylic acid copolymerized with the polyester resin (B) of the present invention include terephthalic acid, isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid and the like. As the aromatic dicarboxylic acid, it is particularly preferable to use terephthalic acid and isophthalic acid in combination from the viewpoint of the properties of the coating film and the solubility. The content of the aromatic dicarboxylic acid is preferably 50 to 100 mol%, more preferably 70 to 100 mol%, and still more preferably 80 to 100 mol%.
Mol%.

The aliphatic and / or alicyclic dicarboxylic acid copolymerized with the polyester resin (B) of the present invention is preferably from 0 to 50.
Mol%, preferably 0 to 30 mol%. These dicarboxylic acids are not essential, but by copolymerizing,
Mainly flexibility can be given, so that workability can be improved.

The aliphatic dicarboxylic acid copolymerized with the polyester resin (B) of the present invention includes succinic acid, glutaric acid, adipic acid, sebacic acid, dodecandionic acid, azelaic acid, dimer acid and the like. Examples of the alicyclic dicarboxylic acid copolymerized with the polyester resin (A) include alicyclic dicarboxylic acids such as 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid. Of these, adipic acid, sebacic acid, and 1,4-cyclohexanedicarboxylic acid are more preferable from the viewpoint of workability, and the content is preferably 30 mol% or less from the viewpoint of acid resistance.

As the glycol component to be copolymerized with the polyester resin (B), other glycols other than the ethylene oxide and / or propylene oxide adduct of bisphenol A and / or bisphenol F represented by the general formula (I) are usually used. Use in combination.

Other glycols include ethylene glycol, neopentyl glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-
Propanediol, 2-butyl-2-ethyl-propanediol, 1,4-butanediol, 1,2-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, , 7-octanediol, 1,9-nonanediol, 3-methyl-1,
5-pentanediol, 3-methyl, 8-methyl-1,
Alkylene glycols such as 8-octanediol,
Examples thereof include alicyclic glycols such as 1,4-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, and TCD glycol, diethylene glycol, polyethylene glycol, and polypropylene glycol.
Other glycols are appropriately selected from economics, physical properties of the coating film, etc., and ethylene glycol, neopentyl glycol, diethylene glycol, 1,4-cyclohexanedimethanol, 1,5-pentanediol, 1,6-hexanediol and the like are used. preferable.

Further, a polycarboxylic acid such as trimellitic acid or pyromellitic acid or a polyhydric polyol such as trimethylolethane, trimethylolpropane, glycerin or pentaerythritol is used in an amount of 0.1 to 3 with respect to the total acid or glycol. When mol% is used, the acid resistance can be further improved.

In the method for producing a polyester resin of the present invention, a direct polymerization method in which dicarboxylic acid and glycol are directly esterified and polymerized at normal pressure or pressure as exemplified in this embodiment, a dimethyl ester of dicarboxylic acid and glycol are used. It is synthesized by a known method such as a transesterification method of polymerizing after transesterification or a method of adding a small amount of xylene and performing a dehydration reaction at normal pressure. As the polymerization catalyst, known catalysts such as a titanium compound such as tetrabutyl titanate shown in this embodiment, a zinc compound, an antimony compound, a tin compound, and a germanium compound are used.

Although the resin properties of the polyester resin (B) of the present invention can be changed depending on the use, the glass transition temperature is preferably from 0 to 80 ° C. If the temperature is lower than 0 ° C., the workability is good, but the scratch resistance, chemical resistance, boiling water resistance, blocking resistance and the like may decrease, which is not preferable. If the temperature exceeds 80 ° C., the acid resistance is good, but the workability may decrease, which is not preferable. Further, the polyester resin (B) of the present invention preferably has a number average molecular weight of 2,000 or more, more preferably 5,000 to 35,000.
If the number average molecular weight is less than 2,000, physical properties such as workability and impact resistance may be reduced.

In the polyester resin (B) of the present invention, a dicarboxylic acid or a glycol containing a sulfonic acid metal base may be used in an amount of 5 mol% or less. Examples of the dicarboxylic acid containing a sulfonic acid metal base include metal salts such as sulfoterephthalic acid, 5-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, and 5 [4-sulfophenoxy] isophthalic acid. it can.
Examples of the glycol containing a sulfonic acid metal base include metal salts such as 2-sulfo-1,4-butanediol, 2,5-dimethyl-3-sulfo-2, and 5-hexanediol. As the metal salt, Li, Na, K, Mg, Ca, C
salts such as u and Fe.

The polyester resin (B) of the present invention may be modified with vinyl with a vinyl polymerizable monomer, modified with an epoxy resin with an epoxy compound, or modified with urethane with an isocyanate compound. When a polyester resin is vinyl-modified with a vinyl polymerizable monomer, an unsaturated double bond containing an unsaturated double bond such as fumaric acid or oleic acid is copolymerized with the polyester resin to introduce an unsaturated double bond into the polyester resin. Then, a method of radically polymerizing the unsaturated double bond and a vinyl compound such as (meth) acrylic ester, styrene, or vinyl acetate in a solution, or a method in which one terminal synthesized from (meth) acrylic ester or styrene is used. It is synthesized by a known method such as directly copolymerizing a macromonomer containing two hydroxy groups into a polyester.

The epoxy resin-modified polyester resin is modified with a terminal carboxy by adding an acid anhydride such as trimellitic anhydride or phthalic anhydride to the terminal hydroxy group of the polyester resin. It can be synthesized by a known method such as a method of epoxy modification in the presence of a catalyst such as phosphine.
The carboxyl group may be introduced by using any carboxyl group-containing glycol of dimethylolpropionic acid as the chain extender.

The urethane-modified polyester resin is synthesized by a known method such as blending a low molecular weight polyester diol with a chain extender if necessary and reacting with a diisocyanate compound. In addition, a carboxyl group may be introduced into a side chain by using a carboxyl group-containing diol such as dimethylolpropionic acid as a chain extender.

The polyester resin (B) of the present invention and / or
Alternatively, a modified polyester (C) obtained by modifying them and a curing agent (D) capable of reacting with them can be blended and used for coating. By adding a curing agent, solvent resistance can be imparted, and various coating film properties such as workability, hardness, stain resistance, chemical resistance, and corrosion resistance can be improved. The amount of the curing agent (D) is {(B) + (C)} / (D) = 95 /
5-60 / 40 is preferable, and 90/10 is more preferable.
７０70/30 (weight ratio). If the blending amount of {(B) + (C)} exceeds 95/5, the coating properties such as chemical resistance, corrosion resistance, and scratch resistance become poor, and if it is less than 60/40, good workability cannot be obtained. There is.

As the curing agent capable of reacting with the polyester resin (B) and / or the modified polyester resin (C), alkyl etherified aminoformaldehyde resin,
Epoxy compounds and isocyanate compounds, phenol resins and the like are mentioned. Among them, an alkyl etherified aminoformaldehyde resin, an isocyanate compound, and a resol-type phenol resin are preferable from the viewpoint of processability. Further, an isocyanate compound is particularly preferable from the viewpoint of acid resistance, and it is preferable to use the isocyanate compound after blocking from storage stability.

As the isocyanate compound, there are aromatic and aliphatic diisocyanates and trivalent or higher polyisocyanates, and either low molecular weight compounds or high molecular weight compounds may be used. For example, tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate or trimers of these isocyanate compounds, and excess of these isocyanate compounds Amount and, for example, ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, low-molecular-weight active hydrogen compounds such as triethanolamine or various polyester polyols,
Examples of the compound include a terminal isocyanate group-containing compound obtained by reacting a polyether polyol, a polyamide with a polymer active hydrogen compound, or the like.

The isocyanate compound is preferably a blocked isocyanate. Examples of the isocyanate blocking agent include phenols such as phenol, thiophenol, methylthiophenol, ethylthiophenol, cresol, xylenol, resorcinol, nitrophenol, chlorophenol, acetoxime, methylethylketoxime, oximes thereof such as cyclohexanone oxime, methanol, ethanol,
Alcohols such as propanol and butanol, halogen-substituted alcohols such as ethylene chlorohydrin and 1,3-dichloro-2-propanol, t-butanol,
Tertiary alcohols such as t-pentanol, lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, β-propyrolactam, and other aromatic amines, imides, Active methylene compounds such as acetylacetone, acetoacetic ester, and malonic acid ethyl ester, mercaptans, imines, ureas, diaryl compounds and sodium bisulfite are also included. The blocked isocyanate can be obtained by subjecting the above isocyanate compound to an isocyanate blocking agent to undergo an addition reaction by a conventionally known appropriate method.

Alkyl etherified aminoformaldehyde resins include, for example, formaldehyde or paraformaldehyde alkyletherified with an alcohol having 1 to 4 carbon atoms such as methanol, ethanol, n-propanol, isopropanol, n-butanol, and urea; Condensation products with N, N-ethylene urea, dicyandiamide, aminotriazine and the like; Butoxylated methylol melamine, mixed methoxylated / butoxylated methylol melamine, butoxylated methylol benzoguanamine, and the like. It preferred from the viewpoint of workability, methoxylated methylolmelamine, butoxy methylol melamine or methoxylated / butoxylated mixed melamine, may be used alone, or in combination.

As the epoxy compound, bisphenol A
Diglycidyl ethers and oligomers thereof, diglycidyl ethers of hydrogenated bisphenol A and oligomers thereof, diglycidyl orthophthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl p-oxybenzoate, tetrahydrophthalate Acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol di Glycidyl ether, 1,6-hexanediol diglycidyl ether and polyalkylene glycol diglycidyl ethers, trime Triglycidyl citrate, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylol ethane triglycidyl ether, trimethylol propane triglycidyl ether, pentaerythritol tetraglycidyl ether And glycerol alkylene oxide adduct triglycidyl ether.

Examples of the phenol resin include a resol type resin obtained by reacting an aldehyde with a phenol in the presence of an alkali catalyst, and a novolak type resin obtained by reacting an aldehyde with a phenol in the presence of an acidic catalyst. And a resol type resin is particularly preferable. Phenols used in these phenolic resins include phenol, o-cresol, p-cresol,
m-cresol, m-methoxyphenol, 2,3-xylenol, 2,5-xylenol, p-tert-butylphenol, p-ethylphenol, bisphenol A, bisphenol F and the like. A condensate thereof, an alkyl etherified product thereof, or a product obtained by subjecting these to various modifications such as epoxy modification, oil modification, melamine modification, and amide modification can be used. Preferable phenols used as a raw material include phenols having three or more functional groups, such as phenol, m-cresol, bisphenol A, and bisphenol F.

It is preferable to use a known curing agent or accelerator selected in accordance with the type of the curing agent in combination with these curing agents.

The baking temperature of the (modified) polyester resin of the present invention is arbitrarily selected depending on the size and thickness of the metal plate, the capability of the baking furnace, the curability of the paint, and the like. A mixer such as a roll mill, a ball mill, a sand mill, and a blender is used for the production of the coating composition. Roller coating, roll coater, spray coating,
Electrostatic painting is selected as appropriate.

The (modified) resin composition of the present invention can be used in accordance with the purpose and use thereof, depending on the purpose and application, such as extender pigments such as titanium oxide, talc, barium sulfate, and clay; Silica, non-polyphosphates such as aluminum tripolyphosphate, zinc phosphate, phosphite, phosphomolybdate, molybdate, cyanamide zinc calcium, borate, calcium silica A chromium-based rust-preventive pigment, a known coloring agent, additives such as silica and wax, a flame retardant, and glass fiber can be blended.

The coating resin composition of the present invention is usually used in the form of a solution in an organic solvent. However, when an ionic group such as the above-mentioned sulfonic acid metal base is introduced, it may be used as an aqueous dispersion. Can also be used. As the organic solvent, for example, toluene, xylene, Solvesso 100,
150, ethyl acetate, butyl acetate, methyl cellosolve,
Ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, methyl cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, methyl carbitol acetate, butyl carbitol acetate, methyl ethyl ketone, cyclohexanone, isophorone, N-methylpyrrolidone, dibasic acid ester, etc. Is appropriately selected in consideration of solubility and evaporation rate. When the (modified) polyester resin of the present invention is used for paints, even if it is applied and baked itself, it shows sufficient performance, so it is suitable for a back coat of a painted metal plate, etc., but is further used as a primer. Preferably, a topcoat known as a topcoat can be applied for the purpose of improving weather resistance, stain resistance, alkali resistance and the like. Further, the (modified) polyester resin of the present invention can be used as an image recording medium by coating it on paper or a plastic film. As compared with the prior art, excellent characteristics such as printability and fingerprint resistance are obtained.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments. In the examples, "parts" means "parts by weight". Each measurement item was in accordance with the following method.

1. Reduced viscosity ηsp / c (dl / g) 0.10 g of a polyester resin was dissolved in 25 cc of a mixed solvent of phenol / tetrachloroethane (volume ratio: 6/4) and measured at 30 ° C.

2. Determination of molecular weight of polyester and addition mole number of alkylene oxide of bisphenol A or bisphenol F By gel filtration chromatography (GPC), the solvent was measured using tetrahydrofuran, and the standard sample was measured using polystyrene. The column is Shodec KF when measuring molecular weight.
802, KF804 and KF806 (Showa Denko KK) were connected in series and used. When measuring the number of moles of alkylene oxide added, use TSKgel SUPERH4000, H
3000 and H2000 (manufactured by Tosoh Corporation) were used in series. The detector used was RI.

3. Determination of the alkylene oxide adduct of isopropenylphenol and the alkylene oxide adduct of vinylphenol as impurities Impurities were measured by gel filtration chromatography (GPC) using tetrahydrofuran as a solvent. The column is TSKg
el SUPERH4000, H3000, H2000
(Manufactured by Tosoh Corporation) were used in series. The detector used UV (254 nm).

4. Glass transition temperature Measured at a heating rate of 20 ° C./min using a differential scanning calorimeter (DSC). The sample was prepared by placing 5 mg of the sample in an aluminum holding lid type container and crimping it.

5. Acid value 0.2 g of sample was precisely weighed and dissolved in 20 ml of chloroform. Then, it was determined by titration with 0.01 N potassium hydroxide (ethanol solution). Phenolphthalein was used as the indicator.

6. Determination of Phosphorus Content A 0.2 g sample was precisely weighed in an Erlenmeyer flask, and 3 ml of sulfuric acid, 0.5 ml of perchloric acid and 3.5 ml of nitric acid were added, and the mixture was gradually heated and decomposed on a hot plate to obtain sulfuric acid white smoke. After allowing to cool to room temperature, the mixture was diluted to about 15 ml with water. One drop of a 0.2% paranitrophenol solution was added, and ammonia water was gradually added while cooling with running water to neutralize sulfuric acid. Then, transfer all the contents to a 50 ml volumetric flask while washing with water, add 5 ml of a 2% ammonium molybdate solution and 2 ml of a 0.2% hydrazine sulfate solution, and adjust the marked lines with water. Mixed. Then, the flask was placed in a boiling water bath for 10 minutes to heat and develop color, and this was water-cooled to room temperature to obtain a test solution. An empty experiment was performed in the same manner. The obtained test solution was measured with a spectrophotometer at a wavelength of 830 nm.
The absorbance was measured using the blank test solution as a control, and the phosphorus content was quantified using a calibration curve prepared in advance. As the phosphorus standard solution, one prepared by dissolving the reagent express potassium dihydrogen phosphate in water was used.

7. Workability The coated steel sheet was bent at 180 degrees, and cracks generated at the bent portions were observed and judged with a 10-fold loupe. 3T refers to a case where three sheets of the same thickness are sandwiched in the bent portion, and 0T refers to a case where the sheet is folded 180 degrees without sandwiching the board.

8. The coated steel sheet was immersed in boiling water for 3 hours, and the state of blisters on the coated surface was evaluated according to ASTM D714-56. When there was no abnormality, it was set to 10.

9. Corrosion resistance The coated steel sheet is a method described in JIS K5400,
A 5% NaCl salt water spray test was performed at 35 ° C. for 1000 hours, and the occurrence of blisters was visually determined. The corrosion resistance was measured for the cross cut portion, the 1T processed portion, and the end face portion.
The evaluation criteria are shown below. 1T processed part or 2T processed part ◎: No abnormality ○: Almost no blister △:
Blister generation ×: remarkable blister generation Cross cut portion (blister blister width) ： １: 1 mm or less ○: 1 to 5 mm △: 5 to 10 m
mx: 10 mm or more End face (blister blister width) ： １: 1 mm or less ：: 1 to 5 mm ：: 5 to 10 m
mx: 10 mm or more

10. Pressure Mark Resistance Styrofoam cut into a cube having a side of 1 cm was placed on a coated steel sheet, and a weight of 1 kg / cm ² was applied thereto and left at 60 ° C. for 2 hours. It was determined based on the appearance of the coating film after the test. ：: No abnormality ○: Styrofoam traces slightly appear ×: Styrofoam traces clearly appear XX: Styrofoam traces are noticeable, and in some cases Styrofoam adheres to painted surface

11. Preparation of Top Coating Paint (I) Commercially available high molecular weight polyester dissolved in advance, Byron 300, 80 solid parts, Byron 200, 20 solid parts (all manufactured by Toyobo Co., Ltd.), methyl etherified methylolmelamine, Sumimar M40S (non-volatile 80%,
25 parts of Sumitomo Chemical Co., Ltd.), 2.5 parts of a 10% benzyl alcohol solution of p-toluenesulfonic acid, 125 parts of titanium oxide, and Polyflow S (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) as a surface smoothing agent. The mixture was dispersed with a glass bead-type high-speed shaker for 8 hours to prepare an overcoat. The solvent used was an appropriate amount of a cyclohexanone / solvesso 150 = 50/50 mixture.

12. Preparation of Topcoat Paint Polyester Resins A to C of the Present Invention
Or comparative polyester resins I to K, 30 solids, methyl etherified methylol melamine, Sumimar M40S
(Non-volatile content 80%, manufactured by Sumitomo Chemical Co., Ltd.) 10 parts, p
-0.5 parts of a 20% benzyl alcohol solution of toluenesulfonic acid, 40 parts of titanium oxide, and 0.2 parts of Polyflow S (manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.) as a surface smoothing agent were added and kneaded in a ball mill for 24 hours. A top coat was prepared. The solvent was cyclohexanone / solvesso 150 =
An appropriate amount of the 50/50 mixture was used.

13. Preparation of Painted Steel Sheet (Specimen) A predetermined primer was applied to a zinc phosphate-treated zinc-coated steel sheet having a thickness of 0.5 mm to a dry film thickness of 5 μm.
Baking was performed at 20 ° C. for 60 seconds. Then, 11. Apply the top coat prepared in step 2 so that the dry film thickness becomes 20 μm.
Baking was performed at 30 ° C. for 60 seconds to produce a coated steel sheet.

Synthesis of Bisphenol A Ethylene Oxide Adduct (a) According to a known method, 2.3 mol of ethylene oxide was added to bisphenol A under pressure using potassium hydroxide as a catalyst and then neutralized with phosphoric acid. . After the reaction, the catalyst residue was filtered by adsorption filtration. The content of phosphorus contained in the obtained ethylene oxide adduct of bisphenol A was measured and found to be 5 ppm. The content of ethylene oxide adduct of isopropenyl phenol is 120
ppm. The results are shown in Table 1.

Synthesis of Bisphenol A Ethylene Oxide Adduct (d) According to a known method, an average of 4.0 mol of ethylene oxide was added to bisphenol A using triethylamine as a catalyst, and then neutralized with succinic acid. It was used as it was without filtration after the reaction. When the phosphorus content of the obtained bisphenol A ethylene oxide adduct was measured, it was less than 2 ppm (lower than the measurement limit). The content of the ethylene oxide adduct of isopropenylphenol was 7,600 ppm. Table 1 shows the results.

In the same manner, alkylene oxide adducts (b) to (j) of bisphenol A or bisphenol F shown in Tables 1 and 2 were synthesized. Synthesis examples (g) to (j) in Table 2 are comparative synthesis examples. In each of the catalysts using potassium hydroxide as a catalyst, the catalyst residue was removed by adsorption filtration so as not to inhibit polymerization, and the phosphorus content was set to approximately 25 ppm or less. Further, the amount of the alkylene oxide adduct of isopropenylphenol or vinylphenol as an impurity is changed by adjusting the reaction temperature. As the reaction temperature increases, bisphenol A or F decomposes, and the amount of these impurities increases.

[0051]

[Table 1]

[0052]

[Table 2]

In Tables 1 and 2, bis A: bisphenol A bis F: bisphenol F EO: ethylene oxide PO: propylene oxide KOH: potassium hydroxide TEA: triethylamine.

Example 1 (Synthesis of Polyester Resin A) 485 parts of dimethyl terephthalate, 485 parts of dimethyl isophthalate, 512 parts of ethylene glycol, and 2.3 mol of bisphenol A ethylene oxide were placed in a reaction vessel equipped with a stirrer, a condenser, and a thermometer. Additive (a) 9
07 parts, zinc acetate 0.44 parts, antimony trioxide 0.4
Three parts were charged and transesterification was performed from 140 ° C. to 220 ° C. over 4 hours. Then, the pressure inside the system was gradually reduced, and the pressure was reduced to 1 mmHg over 60 minutes. Further, the polycondensation reaction was performed at 270 ° C. under a reduced pressure of 0.1 to 0.3 mmHg. The reduced viscosity reached 0.64 dl / g and the number average molecular weight of 21,000 per minute. As a result of composition analysis such as NMR, the obtained polyester resin (A) has an acid component in a molar ratio of terephthalic acid / isosophthalic acid = 50/50 and a glycol component in a molar ratio of ethylene glycol / bisphenol A ethylene oxide.2. 3 mol adduct = 45/55. Also,
The acid value was 12 equivalents / 10 ⁶ g and the glass transition temperature was 76 ° C. There was no abnormal foaming during transesterification and polymerization. This polyester resin (A) is treated with cyclohexanone /
Solvesso 150 (Exxon Chemical Co., Ltd.) = 50/5
0 (weight ratio) at a solid content of 40% to give a varnish with a transparent hue (APHA) of 100. Table 3 shows the results.

Thereafter, Examples 2 to 7 were carried out in the same manner to synthesize polyester resins (B) to (G). Tables 3 and 4 show the results.
Shown in In each case, a good polymerization rate was obtained. In addition, those having low acid value and hue were obtained. However, in Example 6, in which a raw material containing a large amount of an ethylene oxide adduct of isopropenylphenol, which is an impurity, was used, foaming was observed more than in the case where the amount of the impurity was small.

[0056]

[Table 3]

[0057]

[Table 4]

Example 8 (Synthesis of Polyester Resin H) 415 parts of terephthalic acid, 415 parts of isophthalic acid, 384 parts of ethylene glycol, and 2.2 mol of bisphenol F ethylene oxide were added to a reaction vessel equipped with a stirrer, a condenser, and a thermometer. 1128 parts of product (f) and 0.51 part of tetrabutyl titanate were charged,
The esterification reaction was performed for 4 hours up to ° C. Then, the pressure inside the system was gradually reduced, and then reduced to 1 mmHg over 60 minutes.
When the polycondensation reaction was carried out at 70 ° C., the polymer was rapidly polymerized, and reached a reduced viscosity of 0.55 dl / g and a number average molecular weight of 16,000 in 90 minutes. As a result of composition analysis such as NMR, the obtained polyester resin (H) had an acid component in a molar ratio of terephthalic acid / isosophtalic acid = 50/50 and a glycol component in a molar ratio of ethylene glycol / bisphenol F ethylene oxide. 2 mol adduct = 24 /
76. Further, the acid value was 13 equivalents / 10 ⁶ g and the glass transition temperature was 68 ° C. There was no abnormal foaming during esterification and polymerization. When this polyester resin (H) was dissolved in cyclohexanone / solvesso 150 (manufactured by Exxon Chemical Co., Ltd.) = 50/50 (weight ratio) at a solid content of 40%, a varnish having a transparent hue (APHA) 150 was obtained. Table 4 shows the results.

Comparative Example 1 (Synthesis of Comparative Polyester Resin (I)) 485 parts of dimethyl terephthalate, 485 parts of dimethyl isophthalate, 512 parts of ethylene glycol, and ethylene oxide 2 of bisphenol A were placed in a reaction vessel equipped with a stirrer, a condenser, and a thermometer. 0.3 mol adduct (g) 9
07 parts, zinc acetate 0.44 parts, antimony trioxide 0.4
Three parts were charged and transesterification was performed from 140 ° C. to 220 ° C. over 4 hours. At this time, since considerable foaming was observed, it was necessary to reduce the stirring speed and carefully carry out the reaction. Then, the pressure inside the system was gradually reduced.
The pressure was reduced to 1 mmHg over 0 minutes, and the pressure was further reduced to 0.1 to 0.1 mmHg.
The polycondensation reaction was carried out at 270 ° C. under a reduced pressure of 3 mmHg. As a result, remarkable foaming occurred, and a part of the contents came out of the system. Over 80 minutes, a polyester resin having a reduced viscosity of 0.64 dl / g and a number average molecular weight of 21,000 was obtained. As a result of composition analysis such as NMR, the obtained polyester resin (I) was found to have an acid component in a molar ratio of terephthalic acid / isosophthalic acid = 50 /
The molar ratio of the glycol component was ethylene glycol / bisphenol A ethylene oxide 2.3 mol adduct = 45/55. In addition, acid value 40 equivalents / 1
0 ⁶ g, and a glass transition temperature of 76 ° C.. This polyester resin (A) is mixed with cyclohexanone / solvesso 150
(Exxon Chemical Co., Ltd.) = 50/50 (weight ratio) when dissolved at a solid content of 40% to give a transparent hue (APHA)
200 varnishes were obtained.

Thereafter, Comparative Examples 2 to 7 were carried out in the same manner. The results are shown in Tables 5 and 6. In each case, foaming was remarkable as compared with the examples under the same conditions, and polymerization was sometimes difficult under ordinary conditions.

[Table 5]

[0061]

[Table 6]

Example 9 (Evaluation of physical properties of coating film) 40 parts of titanium oxide, 40 parts of strontium chromate, and methyl etherified methylolmelamine as a curing agent (trade name: Sumimar M40S, 100 parts) were dissolved in 100 solid parts of polyester resin (A). 10 parts of a nonvolatile content of 80%, manufactured by Sumitomo Chemical Co., Ltd.) and 2.5 parts of a 10% benzyl alcohol solution of p-toluenesulfonic acid as a curing catalyst were added and dispersed in a bead disperser for 8 hours to prepare a primer coating. . This primer coating composition is used for 13. The coated steel sheet was prepared by applying and baking in the order of the primer and the top coat according to the method described in (1), and a predetermined test was performed. The top coat used was the top coat (I). Table 7 shows the results. Thus, it can be seen that the resin composition for coatings produced by the production method of the present invention is excellent in workability, corrosion resistance and boiling water resistance, and particularly excellent in corrosion resistance and boiling water resistance as compared with the corresponding comparative examples.

The coating compositions of Examples 10 to 16 and Comparative Examples 8 to 12 were prepared in the same manner with the compositions shown in Tables 7 to 9 and applied and baked. Tables 7 to 9 show the test results of the obtained coated steel sheets. However, the mixing ratio of the paint was shown in terms of solid content. Each of the examples shows better coating film properties than the corresponding comparative example, and it can be seen that the comparative polyester has considerably inferior corrosion resistance and boiling water resistance as compared with the corresponding examples. Also in the examples, it can be seen that those using a high-purity raw material containing a small amount of an alkylene oxide adduct of isopropenylphenol or vinylphenol, which are impurities of the raw material, are more remarkably excellent in corrosion resistance and boiling water resistance.

[0064]

[Table 7]

[0065]

[Table 8]

[0066]

[Table 9]

Example 17 (Evaluation as Top Coating Paint) Using a melt of the polyester resin (A),
An overcoat was prepared by the method described in (1). This is referred to as 11. Dry film thickness of 20 without primer
It was applied to a thickness of μm and baked at 230 ° C. for 30 seconds to produce a coated steel sheet. The product was evaluated for pressure-mark resistance and found to be very good, with no trace. Also, it has excellent boiling water resistance. Table 10 shows the results.

The coating compositions of Examples 18 and 19 and Comparative Examples 13 and 14 were prepared in the same manner with the compositions shown in Table 10, and applied and baked. Table 10 shows the test results of the obtained coated steel sheets. All the examples show better pressure mark resistance than the corresponding comparative examples, and it can be seen that the polyester (I), polyester (J), and the like have considerably lower pressure mark resistance than the examples. Also in the examples, it can be seen that those using a high-purity raw material containing a small amount of an alkylene oxide adduct of isopropenylphenol or vinylphenol, which are impurities of the raw material, are more excellent in pressure resistance and boiling water resistance.

[0069]

[Table 10]

Example 20 (Evaluation as Sublimation-Type Thermal Transfer Image-Receiving Layer) The polyester resin (A) was dissolved in a mixed solvent of toluene / methyl ethyl ketone (50/50) to obtain a 20% solution. An epoxy-modified silicone oil (KF-102 manufactured by Shin-Etsu Chemical Co., Ltd.) was added to this solution at 10% by weight based on the resin.
Compounded by Oji Yuka, a synthetic paper with a thickness of 150 μm: Yupo PP
G-150) using a wire bar, and then coated at 120 ° C.
For 30 minutes to obtain a sublimation type thermal transfer image receptor having a dyeing layer having a thickness of 4 μm. It was a sublimation type thermal transfer image receptor having high whiteness. A photographic image was recorded thereon using a commercially available video printer. An image having an excellent color tone without discomfort in both the white portion and the colored portion was obtained. As an evaluation of the durability of the image receiving body, the image receiving body on which the image was recorded was placed in a dark place at 60 ° C. for 1 hour.
It was left for 68 hours. In addition, the image receiver on which an image was recorded was left for two weeks on a window (room) exposed to direct sunlight. In each case, no discoloration or fading was observed, and the image receiver was highly durable. Also, on the surface of the image receiving body on which the image is recorded,
Press your thumb hard so that the fingerprint remains on the image surface,
This image receiver was left in an environment of 40 ° C. After 48 hours, the image was taken out and the image was observed. As a result, there was no aggregation of the dye, no discoloration (color loss), no residue after the fingerprint, and the like, and the image receptor was excellent in fingerprint resistance.

[0071]

According to the production method of the present invention, good workability with less foaming during polymerization can be obtained, so that the contents of the reaction vessel do not overflow, and the polymerization under a higher vacuum and the higher stirring speed can be achieved. It becomes possible and the polymerization rate can be increased.
Further, the obtained polyester resin has less lot variation, and the productivity is greatly improved as compared with the conventional technology.
For this reason, the hue and the acid value of the resin can be kept small. Therefore, by using the coating resin of the present invention as a primer, excellent workability, corrosion resistance, and boiling water resistance can be obtained as compared with conventional polyester resins or epoxy resins, and particularly high workability and corrosion resistance It is useful for home appliances such as refrigerators, washing machines, air conditioner outdoor units, fan heaters, etc., which require boiling water resistance, and for building materials such as metal siding. It is also useful as a top coat or as a one-coat paint which also serves as a primer and provides excellent boiling water resistance and pressure mark resistance. Further, it can be used as an image recording medium by coating on paper or plastic film. By coating with the resin of the present invention, excellent color tone, printability and fingerprint resistance can be obtained as compared with the prior art.

Continued on front page F-term (reference) 4J029 AA01 AB01 AB04 AC01 AC02 AE11 BA02 BA03 BA04 BA05 BA07 BA08 BA10 BD06A BD07A BF09 BF25 BF26 CA02 CA04 CA05 CA06 CA09 CB04A CB05A CB06A CC06A CD03 FC03 FC04 FC05 FC08 FC35 FC36 LA02 NA01 NA03 NA04 NA11 PB11 PC02 PC08 PC10

Claims (3)

[Claims] (1) an aromatic dicarboxylic acid having an acid component of 50 to 1;
0 to 50 mol% of an aliphatic and / or alicyclic dicarboxylic acid, and bisphenol A and / or bisphenol F represented by the general formula (1) as a glycol component
In a process for producing a polyester resin (B) comprising 5 to 100 mol% of an alkylene oxide adduct of the above and 0 to 95 mol% of other polyols, the alkylene oxide adduct of isopropenylphenol and / or the vinyl A process for producing a polyester resin, comprising using an alkylene oxide adduct (A) of bisphenol A and / or bisphenol F having an alkylene oxide adduct content of 20,000 ppm or less. Embedded image (Wherein R ₁ , R ₂ and R ₃ are hydrogen or a methyl group;
m and n are each 1 or more, and at the same time, 2 ≦ m + n
≦ 8. ) 2. A modified polyester resin (C) obtained by further modifying the polyester resin (B) obtained by the method for producing a polyester resin according to claim 1.
Manufacturing method. 3. The polyester resin (B) obtained by the production method according to claim 1 and / or the modified polyester resin (C) obtained by the production method according to claim 2 react with these resins. A resin composition for paints, which comprises the obtained curing agent (D).