JP3434591B2 - Polyol resin and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyol resin and a method for producing the same, and in particular, a cured coating film having excellent flexibility can be obtained by using it as a polyol component of paint, and further, it has a high crosslinking reactivity. The present invention relates to a polyol resin that can be preferably used as a component of a baking paint and the like, and a method for producing the same.

[0002]

2. Description of the Related Art A high molecular weight bisphenol type epoxy resin has a considerable amount of a secondary alcoholic hydroxyl group in the side chain of its molecular chain and can be considered as a kind of polyol resin. Therefore, a high molecular weight bisphenol type epoxy resin is used, for example, as a polyol component of a urethane paint.

[0003]

However, a cured coating film obtained by curing a urethane coating containing a bisphenol type epoxy resin as a polyol component has a drawback that it is brittle due to the rigidity of the bisphenol type epoxy resin itself. is there. Further, in order to save energy in the coating line, a coating composition having a short baking time, that is, a short curing time is required, and the appearance of a polyol component having higher reactivity than that of a conventional bisphenol epoxy resin or the like. Is desired.

Therefore, a first object of the present invention is to obtain a cured coating film having excellent flexibility by using a bisphenol type epoxy resin as a starting material and as a polyol component of a coating material, and further, having a high crosslinking reactivity. Therefore, it is an object of the present invention to provide a method for producing a novel polyol resin capable of obtaining a coating material having a short curing time.

A second object of the present invention is to provide a novel polyol resin obtained by the above method, which is suitable as a polyol component for baking paints and the like.

[0006]

Means for Solving the Problems The present inventors have conducted extensive studies in order to improve the drawbacks of the bisphenol type epoxy resin as such a polyol component. As a result, the bisphenol-type epoxy resin is reacted with bisphenols and a carboxylic acid-terminated polyester resin having an average of two or more carboxyl groups in the molecule to extend the chain length, and at the same time the epoxy groups at both ends of the bisphenol-type epoxy resin are By reacting a monovalent active hydrogen compound capable of reacting with substantially all of the epoxy groups present, it was found that the bisphenol type epoxy resin is hard and brittle and has an appropriate degree of flexibility. I arrived. When a carboxylic acid-terminated polyester resin having an average of two or more carboxyl groups in the molecule is used as the chain extender, the reactivity of the resulting polyol resin with the methylol group-containing compound and the isocyanate compound is improved, It has been found that time baking or lowering of the curing temperature is possible.

That is, according to the present invention, in the presence or absence of the bisphenol (C), (i) the epoxy group in the bisphenol type epoxy resin (A) and two or more carboxyl groups on average in the molecule. Reacting the carboxylic acid-terminated polyester resin (B) with, (ii) reacting the epoxy group in the bisphenol type epoxy resin (A) with the compound (D) having one active hydrogen in the molecule. The present invention provides a method for producing a polyol resin containing substantially no epoxy group, which is characterized in that the steps are carried out so as to satisfy the following formula (1).

[Equation 3] In the above formula, w: amount of bisphenol (C) used (g) x: amount of compound (D) having one active hydrogen in the molecule (g) y: average of 2 carboxyl groups in the molecule Use amount (g) of the carboxylic acid-terminated polyester resin (B) z: Use amount of epoxy resin (g) α: Hydroxyl equivalent of bisphenol (C) (g / eq) β: 1 active hydrogen in the molecule Hydroxyl equivalent or carboxyl group equivalent (g / eq) of the compound (D) having γ: Carboxyl group equivalent (g / eq) of the carboxylic acid terminated polyester resin (B) δ: Epoxy equivalent of epoxy resin (g / eq)

In the present invention, the bisphenol type epoxy resin (A) is obtained as the polyol resin obtained by the above method in the presence or absence of the bisphenol (C).
Average of 2 epoxy groups and 2 carboxyl groups in the molecule
A carboxylic acid-terminated polyester resin (B) having at least one
And a compound (D) having one active hydrogen in the molecule so as to satisfy the following formulas (1) and (2), and the content of the carboxylic acid-terminated polyester resin (B) is 1 to 30. It is intended to provide a polyol resin that is substantially free of epoxy groups, which is weight percent.

[0009]

[Equation 4]

[0010]

[Equation 5]

In the above formulas (1) and (2), w: amount of bisphenol (C) used (g) x: amount of compound (D) having one active hydrogen in the molecule (g) y: Amount of carboxylic acid terminated polyester resin (B) having an average of two or more carboxyl groups in the molecule (g) z: amount of epoxy resin (A) (g) α: hydroxyl group equivalent of bisphenol (C) ( g / eq) β: hydroxyl group equivalent or carboxyl group equivalent (g / eq) of the compound (D) having one active hydrogen in the molecule γ: carboxyl group equivalent (g / eq) of the carboxylic acid terminated polyester resin (B) δ: Epoxy equivalent of epoxy resin (A) (g / eq)

The method for producing the polyol resin of the present invention (hereinafter referred to as "the method of the present invention") and the polyol resin obtained by the production method will be described in detail below.

The method of the present invention comprises bisphenols (C)
In the presence or absence of (i) the epoxy group in the bisphenol type epoxy resin (A) and the carboxylic acid-terminated polyester resin (B) having an average of two or more carboxyl groups in the molecule are reacted. It is a method including a step, and (ii) a step of reacting the epoxy group in the bisphenol type epoxy resin (A) with the compound (D) having one active hydrogen in the molecule. In the method of the present invention, step (i)
The order of performing the step (ii) and the step (ii) is not particularly limited, and the step (ii) may be performed after the step (i), or the step (ii) is performed and then the step (i) is performed. Alternatively, step (i) and step (ii) may be performed simultaneously. Usually, process (i) and process (i
i) can be performed simultaneously without any particular distinction.

The bisphenol type epoxy resin (A) used in the step (i) and the step (ii) carried out by the method of the present invention is, for example, the following general formula:

[0015]

[Chemical 1]

R ² is a hydrogen atom or a methyl group, and R 2
³ is a hydrogen atom, a methyl group or a halogen atom, and n
Is the number of repeating units and is an integer of 0 or more]

Examples include those represented by: The bisphenol-type epoxy resin (A) is obtained by the reaction of bisphenols with epichlorohydrin or β-methylepichlorohydrin, and optionally with chain extension reaction with bisphenols. be able to. In the method of the present invention, the bisphenol type epoxy resin (A) represented by the general formula (I).
Can be used alone or in combination of two or more.

This bisphenol type epoxy resin (A)
Examples of 2,2-bis (4-hydroxyphenyl) propane (commonly known as bisphenol A), bis (4
Examples thereof include glycidyl ethers or bis-methylglycidyl ethers of bisphenols such as -hydroxyphenyl) methane (commonly called bisphenol F) and 1,1-bis (4-hydroxyphenyl) ethane (commonly called bisphenol AD). Among these bisphenol type epoxy resins (A), 2,2-bis (4
The glycidyl ether of -hydroxyphenyl) propane is preferred.

This bisphenol type epoxy resin (A)
Usually has an epoxy equivalent of about 150 to 3500, particularly preferably 170 to 2000. In particular, when the step (i) or the step (ii) is carried out in the presence of a bisphenol (C), the bisphenol type epoxy resin (A) usually has an epoxy equivalent of 160 to 50.
It is preferable to use one of 0. The number average molecular weight (Mn) is usually 300 to 5000, and particularly 35
Those of 0 to 4000 are preferable. The amount of hydrolyzable chlorine in the bisphenol type epoxy resin (A) is 0.002
It is preferably 1.0% by weight, particularly 0.01 to
It is preferably 0.50% by weight.

The bisphenols (C) used in the method of the present invention may be the same as or different from the bisphenols constituting the skeleton of the bisphenol type epoxy resin (A). The bisphenols (C) may be used alone or in combination of two or more.

The carboxylic acid-terminated polyester resin (B) used in step (i) of the method of the present invention has an average of 2 or more, preferably 2 to 3, carboxyl groups in the molecule.
It is a linear polyester resin or a non-linear polyester resin having a carboxyl group at the molecular end. Examples of the linear polyester resin include those obtained by polycondensing a dihydric alcohol and a divalent carboxylic acid, and examples of the non-linear polyester resin include a divalent alcohol and a divalent carboxylic acid, and a polyhydric compound having a valence of 3 or more. Examples thereof include those obtained by polymerizing a polyhydric alcohol or a polyvalent carboxylic acid.

Examples of the dihydric alcohol include ethylene glycol, diethylene glycol, polyethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol and 1,4-butenediol. And diols such as 1,4-bis (hydroxymethyl) cyclohexane, bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A, polyoxypropyleneized bisphenol A, and other etherified bisphenols.

Examples of the divalent carboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, succinic acid, fumaric acid, adipic acid,
Maleic acid, sebacic acid, decamethylene dicarboxylic acid,
Aliphatic dicarboxylic acids such as mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, maconic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, etc. Examples thereof include dicarboxylic acids, acid anhydrides thereof, dimers of lower alkyl esters and linoleic acid, and the like.

Examples of trihydric or higher polyhydric alcohols include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, sucrose, 1 , 2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol,
Trimethylol butane, trimethylol propane, 1,
3,5-trihydroxymethylbenzene etc. can be mentioned.

Examples of the trivalent or higher polycarboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5
-Benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,
2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxylic propane, tetra (methylenecarboxyl) methane, 1,2,7,8- Examples thereof include octane tetracarboxylic acid, acid anhydrides thereof, lower alkyl esters and the like.

The carboxylic acid-terminated polyester resin (B) having these components may be used alone or in combination of two or more. In particular, in the method of the present invention, the carboxylic acid-terminated polyester resin (B) is a carboxylic acid having a minimum constitutional unit of a divalent carboxylic acid such as terephthalic acid and a divalent alcohol such as ethylene glycol or neopentyl alcohol. Acid terminated polyester resins are preferred.

The carboxylic acid terminated polyester resin (B) preferably has an acid value (mgKOH / g) of 20 to 7.
0, more preferably 25 to 40. Also,
The carboxylic acid-terminated polyester resin (B) preferably has a number average molecular weight (Mn) of 1500 to 6000, and particularly has a number average molecular weight (Mn) of 2000 to 500.
Those of 0 are preferred.

As the compound (D) having one active hydrogen in the molecule used in the step (ii), monohydric phenols or monohydric carboxylic acids are usually used. Examples of monohydric phenols include phenol, cresol, isopropylphenol, amylphenol, nonylphenol, todecylphenol, xylenol, p
-Cumylphenol, p-octylphenol and the like. Among these, those having 6 to 40 carbon atoms are preferable. Further, as the monovalent carboxylic acid, for example, acetic acid,
Examples thereof include propionic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, acrylic acid, oleic acid, arachidic acid, linoleic acid, castor oil fatty acid, tall oil fatty acid and the like. Among these, carbon number 6
The thing of -25 is preferable. In the present invention, the compound (D) comprising these components may be used alone or in combination of two or more. Particularly, as the compound (D),
Monohydric phenols such as p-cumylphenol and p-octylphenol are preferable.

The reaction of the epoxy group with the carboxylic acid-terminated polyester resin (B) or compound (D) in the presence of the bisphenol (C) in steps (i) and (ii) is
Usually, it can be carried out at a temperature of 50 to 250 ° C, preferably 100 to 200 ° C.

In the method of the present invention, the reaction in the step (i) or (ii) can be carried out in the presence of a catalyst. Examples of the catalyst to be used include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide, alkali metal alcoholates such as sodium methylate, tertiary amines such as dimethylbenzylamine, triethylamine and pyridine, and tetraamines. Quaternary ammonium salts such as methylammonium chloride and benzyltrimethylammonium chloride, organic phosphorus compounds such as triphenylphosphine, triethylphosphine and triphenylphosphine, sodium carbonate, alkali metal salts such as lithium chloride, boron trifluoride, aluminum chloride, Tin tetrachloride,
A preferable example is a diethyl ether complex of Lewis acids such as boron trifluoride.

The amount of this catalyst used varies depending on the reaction temperature, but is usually 0.1 to 1000 relative to the weight of the product.
ppm, preferably 1 to 100 ppm.

The reaction in steps (i) and (ii) may be carried out without using a solvent or may be carried out using a solvent. When a solvent is used, a solvent having no active hydrogen such as hydrocarbons such as toluene and xylene, ketones such as methyl isobutyl ketone, methyl ethyl ketone and cyclohexanone can be used.

In the above method of the present invention, the carboxylic acid-terminated polyester resin (B) used in step (i) and the compound (D) having one active hydrogen in the molecule used in step (ii) are as follows: The polyol resin is produced by selecting the amount to be used so as to satisfy the two expressions (1) and (2).

[0034]

[Equation 6]

[0035]

[Equation 7]

In the above formulas (1) and (2), w: amount of bisphenol (C) used (g) x: amount of compound (D) having one active hydrogen in the molecule (g) y: Amount of carboxylic acid-terminated polyester resin (B) having an average of two or more carboxyl groups in the molecule (g) z: amount of epoxy resin (A) (g) α: hydroxyl group equivalent of bisphenol (C) (g) / Eq) β: hydroxyl group equivalent or carboxyl group equivalent (g / eq) of compound (D) having one active hydrogen in the molecule γ: carboxyl group equivalent (g / eq) δ of carboxylic acid terminated polyester resin (B) : Epoxy equivalent of epoxy resin (A) (g / eq)

The polyol resin of the present invention obtained by the above-mentioned method of the present invention is substantially free of epoxy groups and is hard and breaks due to a rigid bisphenol skeleton and an ether bond having flexibility. It is a novel resin which has both excellent elongation (tenacity) and excellent flexibility due to the polyester skeleton coexisting in the resin main chain skeleton.

The polyol resin of the present invention has a content of the carboxylic acid terminated polyester resin (B) of 1 to 30.
% By weight.

The hydroxyl value of this polyol resin is
Usually, it is about 150 to 250 KOHmg / g and the softening point is about 70 to 180 ° C. Furthermore, the glass transition temperature is about 50 to 90 ° C., and the number average molecular weight (M
n) is about 800 to 5000.

The polyol resin of the present invention is a baking paint combined with a melamine resin, an amine resin such as a urea resin, a resin having a methylol group such as resole, or a room temperature dry paint containing an isocyanate or a blocked isocyanate, or It can be used as a baking paint.

Further, the polyol resin of the present invention is blended with other polyol resins such as polyester polyol and acrylic polyol, polyethers such as polyethylene glycol and polypropylene glycol, polyester resin, acrylic resin, fiber resin and the like, It can be used as a modifier for these resins.

The polyol resin of the present invention has a temperature of 55 ° C.
Since it has the above Tg, it exhibits good blocking resistance. Therefore, it also has the feature of exhibiting extremely good storage stability in applications where it is stored in a powder state for a long period of time.

When used for various purposes, the polyol resin of the present invention may be inorganic or organic such as talc, calcium carbonate, silica, carbon, petroleum resin, various vinyl compound polymers, tar and asphalt, if necessary. The fillers, pigments, etc. can also be used in combination.

[0044]

EXAMPLES The present invention will be specifically described below with reference to examples. The present invention is not limited to these examples. In the following examples, the epoxy equivalent and the hydroxyl value were measured according to the following methods.

Epoxy equivalent resin 0.2 to 10 g is precisely weighed and put in a 200 ml Erlenmeyer flask, and 25 ml of dioxane is added and dissolved. 1 /
After accurately adding 25 ml of a 5 N hydrochloric acid solution (dioxane solution), the mixture is tightly capped, sufficiently mixed, and then left to stand for 30 minutes. Next, after adding 50 ml of a toluene-ethanol (1: 1, volume ratio) mixed solution, the mixture is titrated with a 1/10 N sodium hydroxide solution using cresol red as an indicator.
Based on the titration result, the epoxy equivalent is calculated according to the following formula.

[0046]

[Equation 8]

W: weight of sample (g) S: titer of 1/10 normal sodium hydroxide solution (m
l) f: titer of 1 / 10N sodium hydroxide Q: titration amount of 1 / 10N sodium hydroxide solution in a blank test (ml)

1.5 to 2.0 g of a hydroxyl value resin is precisely weighed and put in a 25 ml volumetric flask, and filtered with molecular sieve 4A to remove ethanol and purified chloroform from which water is added and dissolved.
After completely dissolving, add 25 ml of purified chloroform.
The sample solution was prepared by adjusting the marked line to l. Next, the sample solution is placed in a KBr solution cell (thickness: 0.2 mm), and the absorbance at a wavelength of 4000 to 3000 cm ^-1 is measured using purified chloroform as a control solution. The absorbances T ₁ and T ₂ of the _two absorption peaks appearing in the absorbance curve are determined with the absorbance of the control solution as the zero standard.

Next, based on the calibration curve prepared in advance according to the following method, T ₁ + T obtained above is calculated.
_The hydroxyl group concentration (eq / l) is calculated from the value of ₂ , and the hydroxyl value is calculated according to the following formula.

[0050]

[Equation 9]

Where F = cell thickness correction factor, F = L
₁ / L ₂ L ₁ = cell thickness at the time of creating the calibration curve (mm) L ₂ = cell thickness used for absorbance measurement (mm)

Preparation of calibration curve Add molecular sieves to each of the six 25 ml flasks.
Purified Diethylene Glycol filtered and dehydrated with a tube 4A
To 0.1, 0.2, 0.3, 0.4, 0.5 and
Collect 0.6 g, add purified chloroform and add 25 ml.
Adjusted to the marked lines, 0.075, 0.151, 0.
226, 0.301, 0.376 and 0.452eq
A standard solution having a hydroxyl equivalent of 1 / l is prepared. These standard solutions
Using a KBr liquid cell (0.2 mm).
Wavelength 4000-3000 cm with rum as control liquid^-1To
The absorbance curve is measured. The two that appear in the absorbance curve
Absorbance T of absorption peak₁And T₂Is the absorbance of the control solution
Is taken as the zero reference, and T₁+ T ₂Value and hydroxyl equivalent
Plot the relationship and use it as the calibration curve.

Number average molecular weight (Mn) Tetrahydrofuran as elution solvent, elution temperature 40 ° C,
It is measured by GPC using HSG20, 40, 50 and 60 manufactured by Shimadzu Corporation as a column. The number average molecular weight is calculated using a bisphenol A type epoxy resin or polystyrene whose molecular weight is known in advance as a standard substance.

Example 1 A bisphenol A type epoxy resin [solid content concentration: 75.2% by weight, xylene concentration was placed in a separable flask having an internal volume of 20 l equipped with a stirrer, a thermometer, an N ₂ inlet and a cooling tube. : 248% by weight, epoxy equivalent of resin: 472, hydrolyzable chlorine concentration:
0.004% by weight, hereinafter referred to as "A-1"] 8533
g, bisphenol A type epoxy resin with high hydrolyzable chlorine content [epoxy equivalent: 214, hydrolyzable chlorine concentration:
2.0% by weight, hereinafter referred to as "A-2"] 575 g, bisphenol A 1117 g, p-cumylphenol 13
91 g, and a carboxylic acid-terminated polyester resin [manufactured by Nippon Yupica Co., Ltd., GV335, acid value: 30 mg KOH /
g, softening point: 135 ° C., number average molecular weight (Mn, GP
C): 3200] (500 g) was charged, and the mixture was melted and homogenized by stirring at a temperature of about 100 ° C.

Then, a lithium chloride aqueous solution (concentration: 0.
(05 g / ml) 37 ml was added, and the temperature was gradually started to rise. In order to suppress heat generation during the reaction, xylene was distilled off under reduced pressure when the temperature of the reaction mixture reached about 130 ° C. Finally set the temperature of the reaction mixture to 1
The mixture was kept at 60 ° C. and stirred for about 8 hours for reaction. As a result of sampling a part of the reaction mixture, the number average molecular weight (M
n) 2510, softening point 129 ° C, Tg by DSC
Is 69 ° C, acid value is 1 mgKOH / g or less, and hydroxyl value is 1
It was 85 mg KOH / g. At this time, the reaction mixture was immediately diluted with an equal weight mixed solvent of cyclohexanone and toluene to obtain a polyol resin solution having a solid content concentration of 44.8% by weight.

(Examples 2 to 8 and Comparative Examples 1 to 3) Bisphenol A type epoxy resin having the properties and amounts shown in Table 1, bisphenols (B), and active hydrogen in the molecule are 1
A polyol resin was produced in the same manner as in Example 1 except that the individual compound and the carboxylic acid terminated polyester resin were used. With respect to the obtained polyol resin, the properties of the solid polyol resin before solvent dilution and the solid content concentration of the solution after solvent dilution were measured. The results are shown in Table 1.

[0057]

[Table 1]

[0058]

[Table 2]

Next, urethane resins (Takenate D-10, manufactured by Takeda Pharmaceutical Co., Ltd.) were added to each of the polyol resins obtained in Examples 1 to 8 and Comparative Examples 1 and 2.
2) was blended so that the NCO / OH equivalent ratio would be 0.8 to prepare a mixture of a polyol resin and a urethane resin.
The mixture of this polyol resin and urethane resin was applied to a polished mild steel plate (SS41) sprayed with a release agent to give a film thickness of 40
A 0μ semi-dry coating was formed. Apply this coating at room temperature for 33
It was left for an hour and further heated at 60 ° C. for 24 hours to obtain a cured coating film. The tensile strength, tensile modulus and elongation of this cured coating film were measured according to the following methods. The results are shown in Table 2.

Tensile strength, tensile modulus and elongation-hardening coating film of the cured coating film were removed from the mild steel plate, and then JIS K-7 was used.
A No. 2 type test piece specified in 113 was cut out. Using this test piece, a tensile test was performed according to JIS K-7113 to measure the tensile strength, tensile elastic modulus and elongation. At this time, the crosshead speed of the tester Tensilon was set to 1 mm / min.

[0061]

Further, the polyol resins obtained in Examples 1 to 8 and Comparative Examples 1 and 2 were subjected to a storage stability test according to the following method. The results are shown in Table 3.

Storage stability test The polyol resin is pulverized using a sample mill.
Next, using a vibrating and sieving machine, 7 mesh (2.83 mm)
A powder of ˜150 mesh (0.105 mm) is classified and collected. Then, 50 cm ³ of the powder prepared above is charged into a glass container having a diameter of 5 cm and a height of 15 cm, and a load of 800 g is applied to the glass container with a weight of SUS made of 5 cm. After being left for 5 days in an atmosphere having a humidity of 60% RH and a temperature of 40 ° C., it is left at room temperature for 3 hours. After the weight was removed, the ease of flow of the powder was visually observed when the glass container containing the powder was horizontally inverted. The results are shown in Table 3.

[0064] Note 1) No problem; powder does not block at all, and it easily flows out in a powder state when falling.

[0065]

According to the method of the present invention, a cured coating film having excellent flexibility can be obtained by using a bisphenol type epoxy resin as a starting material and used as a polyol component of a coating material, and further, it has a high crosslinking reactivity. Therefore, it is possible to produce a novel polyol resin that can obtain a coating material having a short curing time.

Further, since the polyol resin of the present invention can be used as a polyol component of a coating material to obtain a cured coating film having excellent flexibility, and further has a high crosslinking reactivity,
It is useful as a component capable of obtaining a coating material having a short curing time. In particular, when the polyol resin of the present invention is used as the main curing agent and a thermosetting polyester-based resin is used as the overcoat layer as a primer for a pre-coated metal (PCM) coating, a good coating that can withstand severe processing is sufficiently applied. A membrane can be provided.

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-5-247403 (JP, A) JP-A-55-155060 (JP, A) JP-A-48-89248 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C08G 59/00-59/72

Claims (4)

(57) [Claims] 1. A carboxylic acid terminal having (i) an epoxy group in a bisphenol type epoxy resin (A) and an average of two or more carboxyl groups in the molecule in the presence or absence of a bisphenol (C). The steps of reacting the polyester resin (B) and (ii) reacting the epoxy group in the bisphenol type epoxy resin (A) with the compound (D) having one active hydrogen in the molecule are described below. A method for producing a polyol resin containing substantially no epoxy group, which is carried out so as to satisfy the formula (1). [Equation 1] In the above formula, w: amount of bisphenol (C) used (g) x: amount of compound (D) having one active hydrogen in the molecule (g) y: average of 2 carboxyl groups in the molecule Use amount (g) of the carboxylic acid-terminated polyester resin (B) z: Use amount of epoxy resin (g) α: Hydroxyl equivalent of bisphenol (C) (g / eq) β: 1 active hydrogen in the molecule Hydroxyl equivalent or carboxyl group equivalent (g / eq) of the compound (D) having γ: Carboxyl group equivalent (g / eq) of the carboxylic acid terminated polyester resin (B) δ: Epoxy equivalent of epoxy resin (g / eq) 2. The bisphenol type epoxy resin (A)
Has an epoxy equivalent (g / equivalent) of 170 to 2000, a molecular weight of 350 to 4000, and a hydrolyzable chlorine content of 0.02 to 0.50% by weight. Production method. 3. The polyol resin according to claim 1, wherein the carboxylic acid terminated polyester resin (B) has an acid value (mgKOH / g) of 20 to 70 and a number average molecular weight (Mn) of 1500 to 6000. Manufacturing method. 4. A carboxylic acid-terminated polyester resin having an epoxy group in a bisphenol type epoxy resin (A) in the presence or absence of a bisphenol (C) and an average of two or more carboxyl groups in the molecule ( B) and a compound (D) having one active hydrogen in the molecule are reacted so as to satisfy the following formulas (1) and (2),
The content of the carboxylic acid-terminated polyester resin (B) is 1 to
A polyol resin substantially free of epoxy groups, which is 30% by weight. [Equation 1] [Equation 2] In the above formula, w: amount of bisphenol (C) used (g) x: amount of compound (D) having one active hydrogen in the molecule (g) y: average of 2 carboxyl groups in the molecule Use amount (g) of carboxylic acid terminated polyester resin (B) z: Use amount of epoxy resin (A) (g) α: Hydroxyl equivalent of bisphenol (C) (g / eq) β: Active in molecule Hydroxyl equivalent or carboxyl group equivalent (g / eq) of compound (D) having one hydrogen γ: Carboxyl group equivalent (g / eq) of carboxylic acid terminated polyester resin (B) δ: Epoxy equivalent of epoxy resin (A) (G / eq)