JP2002371128A - Solvent-soluble crystalline polyester resin and adhesive composition using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crystalline polyester resin useful for an adhesive to various plastic films, woods, paper, leathers, metals, and anchor coat agents and resin modifiers, having excellent heat resistance and mechanical characteristics, in particular, for electronic wiring parts, as bonding metals to plastic films, having good solubility to general solvents and retraining excellent stability in varnish having high solid concentration. SOLUTION: This solvent-soluble crystalline polyester resin is obtained by including an alicyclic dicarboxylic acid into a component constituting a polyester resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to adhesiveness to various plastic films, wood, paper, leather, metal, etc., and is also useful as various anchor coating agents and resin modifiers. The present invention relates to a polyester resin having excellent properties, exhibiting excellent solubility in a general-purpose solvent, and having good storage stability, and an adhesive composition using the same, for applications such as electric wiring parts for adhering a resin.

[0002]

2. Description of the Related Art Conventionally, polyester resins have been used as adhesives for various materials, and a non-solvent type hot-melt adhesive and a solvent type solvent-based adhesive are used for different purposes and devices. Is the current situation. In recent years, non-solvent type hot melt adhesives have tended to be used frequently due to environmental issues, etc. There is a demand for an adhesive having the same performance as a melt adhesive, being soluble in a solvent, and having excellent storage stability.

[0003] Amorphous polyester resins are easily soluble in solvents but generally have poor heat resistance and low cohesive strength, and thus have low adhesiveness. On the other hand, crystalline polyester resins generally used as hot-melt adhesives have excellent cohesive strength and good adhesiveness, but are generally hardly soluble in solvents, and are solvent-based polyester resins which can satisfy both. Obtaining an adhesive is very difficult.

To solve this problem, Japanese Patent Laid-Open Publication No. Sho 53-7113
No. 8 discloses a method using a block copolymer of polytetramethylene oxide glycol. However, it is not easy to dissolve in toluene, which is a general-purpose solvent. There is a problem with storage stability. Further, as disclosed in JP-A-4-164957, in a method of melting and mixing a non-crystalline polyester resin soluble in a solvent with a crystalline polyester resin,
There is a problem that a large-scale apparatus must be introduced because a melt mixing step is required.

[0005] Saturated polyester-based hot melt resins that have been used in various applications up to now are, for example, despite high heat resistance being listed as a required performance.
To emphasize the production efficiency during bonding (lamination), the softening point of the resin has been lowered to realize low-temperature lamination.

[0006] When the softening point is low, the properties of the resin are impaired, depending on the application and the use environment, such as the workability of the resin being softened and flowing, and the decrease in cohesive force and the decrease in adhesive strength. May go on. Therefore, when the softening point of the resin is increased, the solubility of the solvent tends to be extremely poor. Therefore, it is very important to balance these properties. In particular, when used as an adhesive for electrical wiring components and the like, it is generally necessary to satisfy required performances such as heat resistance, insulation resistance, and wet heat resistance of the adhesive layer.
Due to problems in manufacturing equipment, there is a demand for an adhesive composition that is soluble in a solvent and has excellent storage stability.

For example, Japanese Patent Application Laid-Open No. 06-184515 proposes a crystalline polyester resin having improved solvent solubility and storage stability. Examination of these resins shows that they are excellent in solubility and stability, but have a low softening point, tend to be insufficient in heat resistance, and hardly exhibit performance under severe conditions. When the resin is actually used, it is necessary to increase the solid concentration of the resin with respect to the varnish in consideration of productivity, cost, and the like, but the solution stability at a level that does not cause a practical problem. It is very difficult to make sex possible.

That is, a crystalline polyester resin having high heat resistance, good solubility in a general-purpose solvent, and maintaining excellent stability even in a varnish having a high solid content,
Not yet found.

[0009]

The present invention is useful as an adhesive agent for various plastic films, wood, paper, leather, metal, etc., and also as an anchor coating agent and a resin modifier. For applications such as electronic wiring parts for bonding plastic films, it has excellent heat resistance and mechanical properties, has good solubility in general-purpose solvents, and maintains excellent stability with a varnish with a high solid content. It is an object to provide a crystalline polyester resin.

[0010]

Means for Solving the Problems The present inventors have found that not only are they soluble in general-purpose solvents, but they also have stability in dissolution and storage at high solids concentrations, and have improved adhesiveness, heat resistance, and mechanical properties. As a result of intensive studies to obtain a polyester resin having an excellent softening point, the present invention has been achieved. That is, in the components constituting the polyester resin, a solvent-soluble crystalline polyester resin containing an alicyclic dicarboxylic acid component and an adhesive composition using the same, various plastic films, wood,
It has excellent adhesion to paper, leather, and metal, and is also useful as various anchor coating agents and resin modifiers. Particularly, it has excellent properties for applications such as electronic wiring parts that bond metal and plastic films. Further, the present inventors have found that the varnish has good solubility in general-purpose solvents and retains excellent stability with a varnish having a high solid content, thereby completing the present invention. Hereinafter, the present invention will be described in detail.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The solvent-soluble crystalline polyester resin of the present invention is characterized in that an alicyclic dicarboxylic acid is contained in the constituent components. The alicyclic dicarboxylic acid is a compound having an alicyclic structure in a compound and having two carboxyl groups. By containing the alicyclic dicarboxylic acid, the polyester resin can increase solubility in a solvent while maintaining appropriate crystallinity, and is suitable as a solvent-soluble crystalline polyester resin used for a hot melt adhesive or the like. Show characteristics.

The alicyclic dicarboxylic acid constituting the polyester resin includes 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and (hereinafter sometimes collectively referred to as cyclohexanedicarboxylic acid).
Examples thereof include 1,2-cyclohexanedicarboxylic acid and hydrogenated phthalic anhydride. Among these, 1,4-cyclohexanedicarboxylic acid is preferred.

The preferred upper limit of the content of the alicyclic dicarboxylic acid in the total acid component is 45 mol%, the more preferred upper limit is 40 mol%, the most preferred upper limit is 35 mol%, the preferred lower limit is 5 mol%, and the most preferred lower limit is 10 mol%.

When the content of the alicyclic dicarboxylic acid in all the acid components constituting the polyester resin is less than 5 mol%, the solvent solubility of the resin may be reduced, and the solution stability may be deteriorated. On the other hand, when the content is 45 mol% or more, the cohesive strength of the adhesive is lost and the adhesiveness may be reduced, or the film is stored under a high temperature and high humidity condition in a state of being coated and dried on a film or dissolved in a solvent. In some cases, molecules may be reduced.

The solvent-soluble polyester resin of the present invention preferably contains terephthalic acid as a dicarboxylic acid component in addition to the alicyclic dicarboxylic acid. By using an alicyclic dicarboxylic acid and terephthalic acid together, it is possible to achieve both crystallinity and solvent solubility at a high level.

The preferred upper limit of the terephthalic acid content in the total acid component is 80 mol%, the more preferred upper limit is 75 mol%, the most preferred upper limit is 70 mol%, and the preferred lower limit is 4 mol%.
0 mol%, a more preferred lower limit is 50 mol%, and a most preferred lower limit is 55 mol%.

If the terephthalic acid content in the total acid component is less than 40 mol%, the heat resistance is lost, the adhesiveness is reduced, or the film is dried and coated in a solvent or dissolved in a solvent under high temperature and high humidity conditions. However, when the content exceeds 80 mol%, the softening point becomes extremely high, and the solution stability of the adhesive may be poor.

Further, the solvent-soluble polyester resin of the present invention preferably contains 20% by mole or less of isophthalic acid. It is more preferably at most 15 mol%, further preferably at most 10 mol%, most preferably at most 8 mol%. If the amount of isophthalic acid is more than 20 mol%, it may become cloudy or gel during storage, possibly due to high crystallinity.

By copolymerizing a fatty acid having 6 or more carbon atoms with the solvent-soluble polyester resin of the present invention, the glass transition point (Tg) of the resin can be lowered, and the adhesiveness, particularly the copper foil adhesiveness, can be improved. . The aliphatic dicarboxylic acid having 6 or more carbon atoms referred to herein means that the chain portion and the side chain portion have 6 carbon atoms.
The above aliphatic carboxylic acids are not particularly limited, and for example, adipic acid, azelaic acid, sebacic acid, dodecane diacid, dimer acid and the like can be copolymerized within the above range. In the total acid component,
The preferable upper limit of the content of the aliphatic dicarboxylic acid having 6 or more carbon atoms is 45 mol%, and the more preferable upper limit is 40 mol%. When the content exceeds 45 mol%, the cohesive strength of the resin is reduced and the adhesiveness is reduced. In some cases, the molecules may be reduced during storage under high temperature and high humidity conditions, such as in a state of being coated on a film and dried or in a state of being dissolved in a solvent.

Further, the solvent-soluble crystalline polyester resin of the present invention preferably also contains an alicyclic diol.
The alicyclic diol has an alicyclic structure in the compound and has two hydroxyl groups. By using an alicyclic diol, the balance between crystallinity and solvent solubility can be kept higher.

The alicyclic diols include 1,4-cyclohexane dimethanol, 1.3-cyclohexane dimethanol, 1,2 cyclohexane dimethanol, tricyclodecane dimethanol, hydrogenated bisphenol A, hydrogenated bisphenol S, hydrogen Bisphenol A ethylene oxide adduct, hydrogenated bisphenol S ethylene oxide adduct, hydrogenated bisphenol A propylene oxide adduct, hydrogenated bisphenol S
And propylene oxide adducts. Among them, 1,4-cyclohexanedimethanol, 1.3
-Cyclohexanedimethanol and 1,2 cyclohexanedimethanol are preferred.

The preferred upper limit of the content of the alicyclic diol in the total glycol component is 70 mol%, the more preferred upper limit is 65 mol%, the most preferred upper limit is 60 mol%, the preferred lower limit is 10 mol%, and the more preferred lower limit is 15 mol%, and the most preferred lower limit is 20 mol%.

The glycol component in the polyester resin is 1
When the amount of alicyclic diol is 100 mol%, the amount is 10 mol%
If it is less than 1, the solvent solubility of the resin may be reduced, and the solution stability may be poor. On the contrary, 70 mol%
If it exceeds, the resin softening point may be extremely high, and the solvent solubility and the solution stability may be poor.

The solvent-soluble polyester resin of the present invention preferably contains 1,6-hexanediol as a diol component. By using 1,6-hexanediol, the solubility in a solvent can be improved, and the glass transition point (Tg) can be reduced.

The preferred upper limit of the 1,6-hexanediol content in the total glycol component is 75 mol%, the more preferred upper limit is 70 mol%, the most preferred upper limit is 65 mol%, the preferred lower limit is 10 mol%, and the more preferred lower limit. Is 1
5 mol%, the most preferable lower limit is 20 mol%.

When the content of 1,6-hexanediol in all the glycol components is less than 10 mol%, the solution stability of the adhesive becomes poor, and when it exceeds 75 mol%, the adhesiveness may be reduced.

When the total glycol component constituting the polyester resin of the present invention contains 60 mol% or less of 1,4-butanediol, the softening point is increased, and the heat resistance can be improved. When heat resistance is important, 1,
The preferred content of 4-butanediol is at most 60 mol%, more preferably at most 55 mol%, further preferably at most 50 mol%, preferably at least 25%, more preferably at least 30 mol%. When the content of 1,4-butanediol exceeds 60 mol%, the solvent solubility and the solution stability when used as an adhesive are significantly reduced. When the balance between solvent solubility and solution stability is important,
The content of 4-butanediol is preferably 40 mol% or less, more preferably 30 mol% or less, further preferably 20 mol% or less, particularly preferably 15 mol% or less, and most preferably 10 mol% or less. , 4-butanediol may not be contained.

When the total glycol component constituting the polyester resin of the present invention contains 30 mol% or less of ethylene glycol, the softening point is increased and the heat resistance can be improved, but ethylene glycol decreases the solvent solubility. In some cases, molecules may be reduced during storage under high temperature and high humidity conditions, for example, in a state of being applied to a film, dried and dissolved in a solvent. The preferred amount of ethylene glycol content is 3
It is 0 mol% or less, more preferably 20 mol% or less, further preferably 10 mol% or less, and most preferably 5 mol% or less, and ethylene glycol may not be contained. If the content exceeds 30 mol%, the solvent solubility and the solution stability when used as an adhesive may decrease.

Here, the polyester resin of the present invention may be appropriately copolymerized with the following dibasic acid component and glycol component within the above-mentioned range. Examples of the acid component include orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 2,2′-diphenyldicarboxylic acid, and 4,4′-diphenyletherdicarboxylic acid Aromatic dibasic acids such as acids, adipic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid,
It is an aliphatic or alicyclic dibasic acid such as 4-methyl-1,2-cyclohexanedicarboxylic acid.

The glycol components include propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, and 1,2-butanediol.
1,3-butanediol, 1,5-pentanedio-
, 3-methyl-1,5-pentanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentaneddiol, neopentyl hydroxypivalic acid Esters, ethylene oxide adducts and propylene oxide adducts of bisphenol A, ethylene oxide adducts and propylene oxide adducts of hydrogenated bisphenol A, 1,9-nonanediol, 2-methyloctanediol, Examples thereof include 10-decanediol, 2-butyl-2-ethyl-1,3-propanediol, and tricyclodecanedimethanol. Examples of the polyether polyol include polyethers such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

The glass transition point of the polyester resin of the present invention is preferably in the range of -60 ° C to 20 ° C. A more preferred lower limit is −30 ° C., and a most preferred lower limit is −10 ° C.
° C. When the glass transition point is lower than −60 ° C., the elastic modulus at a high temperature decreases, and the adhesive strength may be insufficient.
For example, when used as an adhesive for automotive parts and home appliances, the adhesive strength decreases in a high temperature environment in summer,
In some cases, it may be difficult to sufficiently adhere the parts to each other. Further, the resin may be easily blocked, and it may be difficult to handle a substrate such as a film after applying the adhesive. On the other hand, when the glass transition point exceeds 20 ° C., the modulus of elasticity near room temperature is increased, and the resin itself is too hard to exhibit adhesiveness to an adherend in some cases.

The softening point of the polyester resin of the present invention (JI
The preferable upper limit of the ring and ball method of S standard K2207 is 1
At 60 ° C, a more preferred upper limit is 150 ° C, a most preferred upper limit is 145 ° C, a preferred lower limit is 100 ° C, a more preferred lower limit is 110 ° C, and a most preferred lower limit is 115 ° C.
It is. When the softening point of the resin is less than 100 ° C., the solubility in a solvent is very good, but the softening point is lowered and the heat resistance may be lowered.

When the softening point of the resin exceeds 160 ° C., the heat resistance is improved, but the solvent solubility tends to be poor. Regarding solvent solubility, even resins having the same softening point differ depending on the magnitude of energy for melting the crystalline state, that is, the degree of crystallinity. When dissolved in a general-purpose solvent, particularly a mixed solvent of toluene and ketone, the crystal melting energy (by differential scanning calorimetry) of the resin of the present invention is 15 mJ / mg.
It is preferably less than 14 mJ / mg, more preferably less than 12.5 mJ / mg, even more preferably 12 mJ / mg or less, particularly preferably 11 mJ / mg or less, and most preferably 10 mJ / mg or less. . When the crystal melting energy is less than 15 mJ / mg, the solvent solubility is good and the stability is further excellent. This is because when the heat of crystal fusion is small, the solubility of the solvent is improved because the degree of crystallinity is low.

[0034] In the solvent-soluble crystalline polyester resin of the present invention, the solvent solubility means toluene, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, ethyl acetate alone or an arbitrary mixing ratio of any plural kinds thereof. 3% or more dissolved at 25 ° C. in any one or more of the following mixed solvents (concentration 3
%, And after storage at 25 ° C. for 24 hours, no gelation or precipitation occurs). In practical use, it is desired that 5% or more, more preferably 10% or more, further preferably 15% or more, particularly preferably 20% or more, and most preferably 22%, be dissolved in at least one of the above solvents.

The term "crystallinity" means that a melting point peak is observed by differential scanning calorimetry (heating rate: 20 ° C./min), and the crystal melting energy is preferably 2 mJ / mg from the viewpoint of maintaining the crystallinity. Above, more preferably 4m
J / mg or more, more preferably 5 mJ / mg or more, particularly preferably 6 mJ / mg or more, most preferably 7 mJ / mg.
/ Mg or more.

When the polyester resin of the present invention is used particularly as an adhesive for electronic parts, it is required to have high adhesiveness to a conductive wire, a substrate and a circuit made of the metal. For this reason, by introducing a carboxyl group into the resin and increasing the adhesion to the metal, the adhesion can be improved. The method for introducing a carboxyl group into the polyester resin is not particularly limited, and can be performed according to a known ordinary method. For example, there is a method in which after the production of polyester, a divalent or higher valent acid anhydride is added to complete the reaction in a molten state. The dihydric or higher acid anhydride includes, for example, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, dodecenyl succinic anhydride, ethylene glycol bistrimellitate, diphenylsulfonetetracarboxylic dianhydride, benzophenonetetracarboxylic acid Anhydrides and the like.

[0037] The acid value of the present invention the polyester resin is preferably 40 eq / 10 ⁶ g or more. Further, it is preferably at least 45 equivalents / 10 ⁶ g. Further, the acid value is preferably from 200 eq / 10 ⁶ g, more preferably 170 or less equivalent / 10 ⁶ g, more preferably 150 equivalents / 10 ⁶ g, even more preferably 130 eq / 10 ⁶
g, particularly preferably 110 equivalents / 10 ⁶ g or less, most preferably equivalents / 10 ⁶ g or less.

When the acid value of the resin is less than 40 equivalents / 10 ⁶ g, the adhesiveness to metal may decrease. Conversely 200
If the equivalent weight is more than 10 ⁶ g, the polyester itself may be hydrolyzed during storage under high-temperature and high-humidity conditions, such as in a state of being coated and dried on a film or in a state of being dissolved in a solvent, and the molecule may be reduced.

The number average molecular weight of the polyester resin of the present invention is preferably about 5,000 to 5,000 (measured by GPC, in terms of styrene), more preferably 10,000 or more, most preferably 15,000 or more, and 45,000.
Or less, more preferably 38000 or less. When the number average molecular weight is small, the adhesive has no cohesive strength and the adhesive strength is reduced. Conversely, if it is large, it becomes hardly soluble in the solvent.

Further, in the present invention, the solvent for dissolving the polyester resin having the above composition to produce a varnish is not particularly limited, but toluene and ketone solvents are more preferable from the viewpoint of versatility and economy. When dissolving the polyester resin of the present invention, the ratio of toluene / ketone is 5/95.
To 50/50% by weight, more preferably 5/50% by weight.
95-30 / 70% by weight, most preferably 10 / 90-
It is characterized by being dissolved in a mixed solvent of 25/75% by weight. At this mixed solvent ratio, the solubility of the resin and the stability of the solution can be sufficiently exhibited.

The ketone is methyl ethyl ketone,
The term refers to ketones such as methyl isobutyl ketone, cyclohexanone, and isophorone, of which methyl ethyl ketone and methyl isobutyl ketone are preferably used. Here, the compounding ratio of the polyester resin of the present invention and the mixed solvent of toluene / ketone is 5/95 to 40/60% by weight.
Is preferably 10/90 to 35/65% by weight, and most preferably 15/85 to 30/70% by weight. When the polyester resin concentration increases, the solution stability of the adhesive becomes poor, and when it decreases, the operation of increasing the number of times of application of the adhesive is required when increasing the thickness of the adhesive layer, resulting in poor efficiency and poor productivity. descend.

When the solubility of a polyester resin such as xylene, ethyl acetate, butyl acetate, ethyl cellosolve, cellosolve acetate, etc. is improved by adding a small amount of a good solvent, these solvents can be used effectively. .

The polyester resin of the present invention can be mixed with various additives and used for an adhesive or a coating agent. As additives, phosphates, phosphorus-based flame retardants such as polyphosphates, nitrogen-based flame retardants such as melamine cyanurates, various flame retardants such as halogen-based flame retardants, talc,
Examples include nucleating agents such as mica, polyethylene, and various metal salts, coloring pigments, inorganic and organic fillers, crosslinking agents, and tackiness improving agents.

The polyester resin of the present invention can be heated and melted as it is to be used as a hot melt adhesive. However, the polyester resin is dissolved in the above organic solvent, coated on a plastic film, and dried. 200 μm to 3 as dry film thickness
μm is preferred. It is more preferably 100 μm or less, further preferably 70 μm or less, more preferably 10 μm or more, and even more preferably 15 μm or more.

As the plastic film, any plastic film such as a polyester film, a polyamide film, a polycarbonate film, a polypropylene film, a polystyrene film, a polyimide film, a polyamideimide film, and a polyoxabenzazole film is used, but a polyester film is preferable. . An easy-adhesion layer can be provided on the plastic film.

The thus-obtained plastic film coated with the polyester resin of the present invention can be superimposed on another material or plastic film, and bonded by heating and pressing. As other materials, metals are preferred, and copper foil and copper wire are preferred when used as electric wiring parts and electric circuits.

The polyester resin of the present invention and the adhesive composition using the same exhibit excellent adhesiveness to PET films and copper foils. It is very suitable for use as an adhesive for cables and the like.

[0048]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. The measured values described in the examples were measured by the following methods.

[0049] Composition: dissolving the resin in heavy chloroform, ¹
It was quantified by 1 H-NMR and ¹³ C-NMR. Glass transition point: Using a differential scanning calorimeter, measurement sample 10 m
g into an aluminum pan, hold the lid tightly and seal, 20 ℃ / m
The temperature was measured at a rate of temperature increase of in. Acid value: The resin was dissolved in chloroform and determined by neutralization titration with an ethanol solution of potassium hydroxide. Number average molecular weight: Measured by gel permeation chromatography using a tetrahydrofuran solvent and a polystyrene standard. Softening point: Evaluated according to the ring and ball method according to JIS K2207. Heat of crystal fusion: using a differential scanning calorimeter, measurement sample 10 mg
Into an aluminum pan, hold the lid tightly and seal, 20 ℃ / mi
n was measured at a heating rate of n to determine the heat of fusion. The device is DS
C220C (manufactured by Seiko Instruments) was used. Varnish stability: toluene / methyl ethyl ketone = 80/2 so that the polyester resin has a solid concentration of 25%.
It was dissolved in 0% of a mixed solvent, and the B-type viscosity (25 ° C.) was measured. Next, the varnish was allowed to stand at 25 ° C. for one week,
The mold viscosity (25 ° C.) was measured and evaluated by the increase rate of the B-type viscosity shown below.

Adhesion to PET: An adhesive composition was prepared by dissolving a polyester resin in a mixed solvent of toluene / methyl ethyl ketone = 80/20% so as to have a solid content concentration of 25%. It was applied on a stretched PET film and dried at 120 ° C. for 15 minutes. The coating thickness was adjusted so that the thickness of the adhesive layer was 30 μm. The adhesive layers were combined and bonded using a roll laminator manufactured by Tester Sangyo Co., Ltd. The lamination was performed at a temperature of 170 ° C., a pressure of 9.8 × 10 ⁴ Pa, and a speed of 0.5 m / min. The adhesive strength was measured using an autograph manufactured by Shimadzu Corporation.
The T-peel adhesion was measured in a 5 ° C. and 60 ° C. atmosphere at a pulling speed of 50 mm / min.

Adhesion to copper foil: Polyester resin was dissolved in a mixed solvent of toluene / methyl ethyl ketone = 80/20% so as to have a solid concentration of 25% to prepare an adhesive composition. It was applied on an axially stretched PET film and dried at 120 ° C. for 15 minutes. The coating thickness was adjusted so that the thickness of the adhesive layer was 30 μm. The adhesive layer and the copper foil were combined and bonded using a roll laminator manufactured by Tester Sangyo. The lamination was performed at a temperature of 170 ° C., a pressure of 9.8 × 10 ⁴ Pa, and a speed of 0.5 m / min. The adhesive strength was measured using an autograph manufactured by Shimadzu Corporation.
The T-peel adhesion after one day of storage at room temperature was measured at a pulling speed of 50 mm / min in an atmosphere of 5 ° C. and 60 ° C.

<Example 1> The present invention is specifically illustrated by examples. In the examples, “parts” means “parts by weight”. In the examples, "%" means on a weight basis unless otherwise specified. In a reaction vessel equipped with a stirrer, a thermometer, and an outflow cooler, 272 parts of dimethyl terephthalate,
162 parts of 1,4-butanediol, 142 parts of 1,6-hexanediol, 1,4-cyclohexanedimethanol 1
44 parts, 0.27 parts of tetrabutyl titanate were charged,
The transesterification was carried out at 180-220 ° C for 2 hours. Next, after the transesterification reaction, the reaction system was heated to 175 ° C.
The temperature was lowered to 1,4-cyclohexanedicarboxylic acid 3
4 parts and 81 parts of sebacic acid were charged, and an esterification reaction was performed at 240 ° C. After the completion of the esterification reaction,
While the temperature was raised from 275 ° C. to 275 ° C., the pressure inside the system was gradually reduced to 500 Pa over 60 minutes. Then, a polycondensation reaction was further performed at 130 Pa or less for 65 minutes to obtain a polyester. After completion of the polymerization, the reaction system was cooled to 200 ° C., 1.9 parts of trimellitic anhydride was added, and the mixture was stirred in a molten state for 30 minutes to obtain a target polyester. As a result of ¹ H-NMR and ¹³ C-NMR analysis, the polyester resin of the present invention showed 70 mol% of terephthalic acid, 11 mol% of 1,4-cyclohexanedicarboxylic acid, 19 mol% of sebacic acid, 1,4
-Butanediol 35 mol%, 1,6-hexanediol 35 mol%, 1,4-cyclohexanedimethanol 3
It has a composition of 0 mol% and a number average molecular weight of 2500.
0, glass transition point is 0 ° C, softening point is 141 ° C, acid value is 110
Equivalent weight / 10 ⁶ g of a white crystalline resin.

<Examples 2 to 8, Comparative Examples 1 to 5>
In the same manner as in Example 1, a polyester resin was obtained using the raw materials shown in Tables 1 and 2, and each evaluation of the resin composition was performed in the same manner as in Example 1. As shown in Table 1, it is understood that the polyester adhesive of the present invention has higher solution stability, adhesiveness, and softening point (heat resistance) as compared with the prior art.

On the other hand, as can be seen from Table 2, Comparative Examples 1 and 2 are excellent in heat resistance and PET adhesion, but since the alicyclic dicarboxylic acid is not copolymerized, the crystallization heat of fusion is low. And the solvent solubility and dissolution stability are poor.

Comparative Example 3 was excellent in heat resistance, PET adhesion at 25 ° C. and adhesion to copper foil, but was poor in solvent solubility and dissolution stability because alicyclic dicarboxylic acid was not copolymerized. is there. Also, since the Tg of the resin is low, PE at 60 ° C.
T adhesion is also low.

Comparative Example 4 is excellent in heat resistance, PET adhesion at 25 ° C. and adhesion to copper foil, but has poor solvent solubility and dissolution stability because the alicyclic dicarboxylic acid is not copolymerized. is there. Also, since the Tg of the resin is low, PE at 60 ° C.
T adhesion is also low.

Comparative Example 5 is excellent in PET adhesion at 25 ° C. and adhesion to copper foil, but is poor in solvent solubility and dissolution stability because alicyclic dicarboxylic acid is not copolymerized.
Further, since the Tg of the resin is low, the PET adhesion at 60 ° C. is also low.

Comparative Example 6 was excellent in PET adhesion, but was not copolymerized with an alicyclic dicarboxylic acid.
Poor dissolution stability.

[0059]

[Table 1]

[0060]

[Table 2]

[0061]

The crystalline polyester resin obtained by the present invention has excellent adhesiveness to various plastic films, wood, paper, leather, metal, etc., and has good solubility in general-purpose solvents, and has high solubility. Superior stability is maintained with a varnish having a solid concentration. Further, it is also useful as various anchor coating agents and resin modifiers, and exhibits excellent heat resistance and mechanical properties particularly in applications such as electronic wiring parts for bonding a metal and a plastic film.

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 4J029 AA03 AB01 AD01 AD02 AD05 AD08 AE13 BA02 BA03 BA05 BA07 BA08 BA09 BA10 BD03A BD07A BD10 BF25 BF26 CA02 CA06 CB06A CD03 4J040 ED041 KA23 LA01 LA02 LA06 LA08 MA02 MA10 MA10 MA10

Claims (3)

[Claims] Claims: 1. A polyester resin comprising:
Solvent-soluble crystalline polyester resin containing an alicyclic dicarboxylic acid 2. An adhesive composition comprising the polyester resin according to claim 1 and an organic solvent. 3. A laminate comprising at least a plastic film layer, an adhesive layer containing the polyester resin according to claim 1, and a metal layer.