JPH0571609B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a copolymerized polyester coating agent,
This invention relates to copolyester useful as various binders. Aromatic polyesters, represented by polyethylene terephthalate, have excellent mechanical, chemical, and electrical properties, and are therefore used in fibers, films, molded products, and the like. However, it has poor solubility in many general-purpose organic solvents, which limits its use in applications such as binders.
Furthermore, although Japanese Patent Publication No. 39-24729 discloses an aromatic copolyester that is soluble in general-purpose organic solvents, it is not sufficiently soluble, and if the dissolved product is stored for a long period of time, There were many practical problems, such as insoluble low-molecular compounds precipitating and the solution becoming cloudy. When used as a coating agent, it significantly impairs the smoothness of the coated surface, and when used as a binder for ink or various paints, it may impede the dispersibility of pigments or cause reaggregation of uniformly dispersed pigments in ink paints. I was getting used to it. In view of the above circumstances, the present inventors have developed a material that can be widely used as a binder for coating agents, inks, paints, etc., has excellent general-purpose solvent solubility and long-term solution stability, and has excellent pigment dispersibility. As a result of intensive study on polymerized polyester, the present invention was arrived at. That is, the present invention provides copolymerized polyesters (excluding crystalline ones) obtained by reacting (a) at least two glycols or their ester-forming derivatives and (b) at least one carboxylic acid or its ester-forming derivatives. ), the 3 glycol components are (1) neopentyl glycol, (2) cyclohexanedimethanol, and (3) the carboxylic acid components other than (1) and (2) are (4) isophthalic acid, (5) orthophthalic acid. It is a copolymerized polyester consisting of an acid and (6) the above (4), (5) and a dicarboxylic acid other than terephthalic acid, each component falling within the range shown by the following formula, and having excellent solubility in organic solvents. 90／10＞(1)／(2)≧20／80 40／100≧(3)／(1)＋(2)＋(3)≧0 99／1≧(4)／(5)≧50／ 50 20/100>(6)/(4)+(5)+(6)≧0 By including neheopentyl glycol and cyclohexanedimethanol, the solubility in general-purpose organic solvents is improved and This enables long-term storage of products. Therefore, when the copolyester obtained by the present invention is used as a coating agent, ink, paint, binder, etc., it has excellent coating film smoothness, pigment dispersibility, etc. The copolyester of the present invention is produced from at least two glycols or ester-forming derivatives thereof and at least one dicarboxylic acid or ester-forming derivative thereof. The glycol used in the present invention contains neopentyl glycol and cyclohexanedimethanol as essential components, and glycols used in addition to these glycols include aliphatic glycols having 2 to 13 carbon atoms. Aliphatic glycols having 2 to 13 carbon atoms include ethylene glycol, propylene glycol, 1,3
-propanediol, 1,4-butadiol,
Aliphatic glycols such as 1,5-pentanediol, 1,6-hexanediol, 1,10-decamethylene diol, diethylene glycol, and 2
-Methyl-2-(dimethylaminomethyl)-1,3
-propanediol, 2-ethyl-2-(diethylaminomethyl)-1,3-propanediol,
Examples include nitrogen-containing fatty acid glycols such as N-methyldiethanolamine and N-butyldiethanolamine. In the present invention, it is necessary that the ratio of glycol component (1) to component (2) be less than 90/10 to 20/80. When (1)/(2) becomes 90/10 or more or less than 20/80, solubility in solvents and storage stability decrease. In addition, the proportion of the glycol component (3) in the gold glycol component is preferably 40 mol% or less.
It is 0.5-20 mol%. If it exceeds 40 mol%, solubility in organic solvents, storage stability, and adhesion will decrease. Carboxylic acids that can be used in the present invention include aromatic dicarboxylic acids such as isophthalic acid, orthophthalic acid, and 2,6-naphthalene dicarboxylic acid, and aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedioic acid. be. The essential components are (4) isophthalic acid and (5) orthophthalic acid. (4), (5) and dicarboxylic acids other than terephthalic acid
Examples of (6) include aromatic dicarboxylic acids such as 2,6-naphthalenedicarboxylic acid, dicarphonic acids containing sulfonic acid metal bases such as 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid, and sodium sulfoterephthalic acid; and phosphorus-containing dicarboxylic acids represented by the following general formulas [], [], and succinic acid, adipic acid, sebacic acid,
Mention may be made of aliphatic dicarboxylic acids such as dodecanedioic acid.

[Formula, R ₁ is a monovalent ester-forming functional group. _{R 2} and R ₃ are the same or different groups,
It is selected from the group consisting of a monovalent hydrocarbon group having 1 to 10 carbon atoms, a halogen atom, and a monovalent ester-forming functional group. A represents a divalent or trivalent organic residue. Further, n ₁ is 1 or 2, and n ₂ and n ₃ each represent an integer of 0 to 4. )

[Chemical formula] (In the formula, R ₄ is a hydrogen atom, a carbon hydrogen group having 1 to 12 carbon atoms that may contain an ester-forming functional group, or M ₂ . _{R 5} is a divalent or trivalent group having 1 to 6 carbon atoms.
valent carbon-hydrogen group. R ₆ is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms that may contain a hydroxyl group, or
M ₃ , M ₁ , M ₂ and M ₃ are alkali metal atoms. m is 0
Or 1l represents an integer of 1 or 2. ) In the present invention, in the copolymerized polyester from which the acid component is obtained, the molar ratio is 99/1≧(4)/(5)≧50/50 20/100≧(6)/(4)+(5)+ It is preferable to react so that the ratio of (6)≧0 is achieved. If the ratio of component (4) to component (5) in the copolymerized polyester exceeds 99/1, the solubility in organic solvents will be poor, and if it is less than 50/50, the adhesion to polyester films, etc. will decrease. There is.
The proportion of the copolymerized polyester component (6) in the total dicarboxylic acid components ranges from 0.5 mol% to less than 20 mol%, and when it exceeds 20 mol%. The cohesive force of the copolymerized polyester may decrease, it may become sticky, and its hydrolysis resistance may deteriorate, making it unsuitable for practical use as a coating agent, binder, etc. The copolymerized polyester of the present invention has greatly improved solvent solubility and storage stability compared to known polyesters, and is also excellent when used as a binder for fine powder particles in pigments, magnetic paints, etc. Demonstrates dispersibility of fine powder particles such as pigments. For use as a binder, particularly desirable polyester compositions are as follows. Acid components include isophthalic acid 90-50 mol%, orthophthalic acid 9-49 mol%, sulfonic acid metal base-containing dicarboxylic acid and/or general formula [], []
1 to 20 mol% of phosphorus-containing dicarboxylic acid. Neopentyl glycol as a glycol component
80-30 mol%, 20-50 mol% 1,4-cyclohexanedimethanol, and 0-25 mol% aliphatic glycol having 2-4 carbon atoms. The method for producing the copolyester in the present invention is not particularly special, and may be a direct esterification method between an acid and a glycol, a transesterification method between an alkyl ester of a carboxylic acid and a glycol, or a glycol decomposition method for a high-molecular polyester. This may be used to obtain a glycol ester of an acid, which is then polymerized by any known method such as melt polymerization. In addition to the above-mentioned components when producing a copolyester, other ingredients such as glycerin, pentaerythritol, trimellitic acid, pyromellitic acid, etc. can also be used within the range that does not impair the performance of the copolyester that yields trifunctional or higher functional polyols or polycarboxylic acids. . The copolymerized polyester obtained by the present invention is amorphous, and not only has excellent solubility and storage stability in organic solvents, but also has excellent adhesion to polyester films, etc., and also has various pigments. It has excellent dispersibility. The copolymerized polyester of the present invention has excellent solubility in organic solvents, and the organic solvents used in the present invention include aromatic hydrocarbons such as toluene and xylene, methyl ethyl ketone, methyl isobutyl ketone, Ketones such as cyclohexanone,
Examples include ester types such as ethyl acetate, butyl acetate, and cellosolve acetate, cyclic ether types such as tetrahydrofuran and dioxane, and amide types such as dimethylformamide, each of which may be used alone or in combination of two or more types as required. can be used. Although the copolymerized polyester of the present invention can be used alone, it can be used in combination with a curing agent such as a polyisocyanate compound, a polyepoxy compound, or an alkyl etherified formaldehyde resin. In addition, other polyester resins, vinyl chloride resins, acrylic resins, polyurethane resins,
It can also be used in a mixed system with known resins such as phenoxy resins. Furthermore, it can also be used for modified resins using diisocyanate compounds or modified resins using diisocyanate compounds and hydroxyacrylate compounds. The copolymerized polyester of the present invention is used after being dissolved in an organic solvent, but it can also be used in the form of the dissolved product as it is, or if necessary, in the form of blending fine powder particles.The fine powder particles include calcium carbonate. , silica, magnesium oxide, tin oxide, carbon, ferrite, cobalt oxide, silver powder, iron powder, alloy powder such as iron-cobalt-nickel, and the like. The copolyester of the present invention not only has excellent thermal properties, mechanical properties, adhesive properties, and pigment dispersibility, but also has excellent solvent solubility and storage stability, and can be used as a coating agent for metal and plastic films. It can be used as a binder for paints and inks. This will be explained in more detail with reference to Examples below.
Of course, it is not limited to these. In addition, in the examples, parts simply mean parts by weight. Example 1 581 parts of isophthalic acid, 200 parts of phthalic anhydride, 5-
Sodium sulfoisophthalic acid 40 parts, ethylene glycol 248 parts, cyclohexanedimethanol 350 parts
1 part, 364 parts of neopentyl glycol, and 0.53 parts of tetrabutoxytitanium were charged into 3 autoclaves, and an esterification reaction was carried out at 200°C to 230°C for 3 hours. Next, the temperature was raised to 250°C over 30 minutes, and at the same time the pressure was gradually reduced to distill off excess glycol at 250°C and 10 mmHg.Finally, a polycondensation reaction was carried out for 90 minutes at 260°C and 0.1 to 0.3 mmHg, resulting in a pale yellow color with a reduced viscosity of 0.58. A transparent copolymerized polyester (A) was obtained. According to the analysis results such as NMR, the composition of the copolyester was as follows. Acid components include 70 mol% of isophthalic acid, 27 mol% of orthophthalic acid, and 3 mol% of 5-sodium sulfoisophthalic acid. Glycol components include cyclohexanedimethanol 49 mol%, neopentyl glycol 47 mol%, and ethylene glycol 14 mol%. The reduced viscosity was measured at 30°C in phenol/tetrachloroethane = 60/40 (weight ratio). Copolymerized polyester (A) was dissolved in a mixed solvent of methyl ethyl ketone/toluene = 20/80 (weight ratio) to a solid content concentration of 40% by weight, and left to stand in an atmosphere at 4°C for 6 months, but no gel formed. No changes such as clouding or clouding were observed, and the product had excellent storage stability. Similarly, copolymerized polyesters (B) to (I) were prepared and their solubility in organic solvents and storage stability were evaluated. The results are also shown in Table 1.

【table】

[Table] Example 2 After dissolving the copolymerized polyesters (A) to (D) of the present invention in methyl ethyl ketone/toluene 20/80 (weight ratio) to a solid content concentration of 40%, Coronate L
(manufactured by Nippon Polyurethane Industries) was added in a solid content of 10% by weight, and then applied to the surface of a 25μ thick polyethylene terephthalate film to a film thickness of 10μ.
After drying at 100°C for 5 minutes, it was cured at 80°C for one day and night. After making 25 squares with a width of 2 mm on this coating film, an adhesion test using cellophane tape was conducted, and no peeling of the coating film was observed. Comparative Example 1 When an adhesion test was conducted using copolymerized polyester (J) instead of the copolymerized polyester of Example 2, 60% of the grid patterns were peeled off. The reduced viscosity of the copolymerized polyester (J) was 0.18, and its composition was 100 mol% of orthophthalic acid as an acid component, 85 mol% of neopentyl glycol and 15 mol% of ethylene glycol as glycol components. Example 3 After dissolving 1200 parts of copolymerized polyester (B) in 544 parts of methyl ethyl ketone and 1000 parts of toluene, 243 parts of diphenylmethane diisocyanate and 0.24 parts of dibutyltin dilaurate were added, and the mixture was reacted at 70 to 80°C for 2 hours. , 52 parts of neopentyl glycol were added, followed by 1200 parts of methyl ethyl ketone and toluene.
744 parts were added and reacted at 80°C for 5 hours. The obtained isocyanate-modified polyester (K) solution had a solid content concentration of 30% by weight and was transparent and pale yellow. When this solution was stored at 4°C for 6 months, no change in appearance was observed and it had excellent storage stability. Approx. 25μ thick polyester film
A coating film of 10μ polyester (K) was created, and Example 2
A cellotape peeling test was conducted in the same manner as above, and it was found to have excellent adhesion. Comparative Example 3 In the same manner as in Example 1, the acid components were 32 mol% of isophthalic acid, 50 mol% of terephthalic acid, and 18 mol% of sebacic acid, and the glycol components were 56 mol% of neopentyl glycol and 20 mol% of 1,4-cyclohexanedimethanol. A copolymerized polyester (L) having a mol% of ethylene glycol of 24 mol% and a reduced viscosity of 0.60 was obtained, and the solvent solubility and solution retention stability were evaluated in the same manner as in Example 1. Methyl ethyl ketone/toluene 20/80 (polymerization ratio)
It was easy to dissolve the solid content in a mixed solvent of 40% by weight, but when this solution was left to stand in an atmosphere at 4°C, it became cloudy within a month and its storage stability was poor. It was hot.

Claims (1)

[Scope of Claims] 1. A copolymerized polyester (crystalline (excluding those in Acid component (4)
isophthalic acid, (5) orthophthalic acid and (6) the above
A copolymerized polyester consisting of (4), (5) and a dicarboxylic acid other than terephthalic acid, each component falling within the range shown by the following formula, and having excellent solubility in organic solvents. 90／10＞(1)／(2)≧20／80 40／100≧(3)／(1)＋(2)＋(3)≧0 99／1≧(4)／(5)≧50／ 50 20／100＞(6)／(4)＋(5)＋(6)≧0