JP5799987B2 - Crystalline polyester resin and adhesive composition using the same - Google Patents

Description

  The present invention is excellent in adhesiveness to various plastic films, wood, paper, leather, metals, etc., and in particular, in flexible flat cable applications used for wiring of electric and electronic devices, polyester film, tin-plated copper and A crystalline polyester resin having excellent adhesion and heat resistance to electrolytic copper foil, excellent solubility in general-purpose solvents, and good storage stability, and an adhesive composition using the same It is.

Conventionally, polyester resins have been used as adhesives for various materials. Currently, solvent-free hot-melt adhesives and solvent-based solvent-based adhesives are used differently depending on applications and devices used. In recent years, solvent-free hot-melt adhesives tend to be used frequently due to environmental problems, etc., but there is still a lot of demand due to the thin film coating that is characteristic of solvent-based adhesives and ease of work. There is a need for a crystalline polyester adhesive that has the same performance as a melt adhesive, is soluble in a solvent, and has excellent storage stability.

An amorphous polyester resin is easily soluble in a solvent, but generally has poor heat resistance, and its cohesive force is small, so that the adhesiveness is also low. On the other hand, a crystalline polyester resin generally used as a hot-melt adhesive is generally a solvent-based polyester resin system that has excellent cohesive strength and good adhesion, but is generally poorly soluble in solvents and can satisfy both. Obtaining an adhesive is very difficult.

In order to solve this problem, as shown in Patent Document 1, in the method of melt-mixing a crystalline polyester resin and a non-crystalline polyester resin soluble in a solvent, a large-scale apparatus is introduced because a melt-mixing step is required. The problem of having to do arises.
JP-A-4-164957

Saturated polyester hot melt resins that have been used in various applications so far, for example, in order to place importance on production efficiency at the time of bonding (laminate), despite the fact that high heat resistance has been cited as a required performance The low melting point of the resin has been achieved to achieve low temperature lamination. If the melting point is low, depending on the application and usage environment, the resin will soften and flow, so the workability will decrease, and the cohesive strength will decrease and the adhesive strength will decrease, and the properties of the resin will be impaired. is there. Therefore, since the solvent solubility tends to be very poor when the melting point of the resin is increased, it is very important to balance these characteristics.

For example, Patent Document 2 proposes a crystalline polyester resin having improved solvent solubility and storage stability. When these resins were examined, they were excellent in solubility and stability, but because of their low melting point, they seem to have insufficient heat resistance and cannot be used in high temperature environments. In addition, when actually using a resin, it is necessary to increase the solid concentration of the resin relative to the varnish, considering the productivity, cost, etc., but the solution stability at a level that does not cause any practical problems. It is very difficult to make sex possible.
JP-A-6-184515

In particular, when used as an adhesive for wiring of electrical and electronic equipment, it is necessary to satisfy the required performance of the heat resistance, blocking resistance, and adhesiveness of the adhesive layer. There is a need for an adhesive composition that is soluble in water and is excellent in storage stability.

A multi-core flat type flexible flat cable (hereinafter sometimes abbreviated as FFC) frequently used for wiring between circuit boards of electric and electronic devices is an insulating film made of tin-plated copper, which is a conductor, through an adhesive. That is, an insulating film / adhesive / metal conductor / adhesive / insulating film structure. As the insulating film, a biaxially stretched polyethylene terephthalate film layer having excellent mechanical properties and electrical properties is often used.

Recently, FFC is often used in various parts of automobile applications, and accordingly, the use environment temperature is increased and the demand for heat resistance is increased. So far, amorphous polyester has been mainly used for FFC adhesives, but mechanical strength is reduced at 80 ° C or higher, resulting in poor adhesion and deformation of the adhesive layer. Unbearable to use. In other words, there is a need for a crystalline polyester resin that has excellent heat resistance, blocking resistance, adhesion, solubility in general-purpose solvents, and excellent stability even in varnishes with a high solid content. Yes.

  The present invention is excellent in adhesiveness to various plastic films, wood, paper, leather, metals, etc., and in particular, in flexible flat cable applications used for wiring of electric and electronic devices, polyester film, tin-plated copper and A crystalline polyester resin having excellent adhesion and heat resistance to an electrolytic copper foil, excellent solubility in general-purpose solvents, and having a good storage stability in a dissolved material, and an adhesive composition using the same It is about things.

As a result of intensive studies, the present inventors have found that the above problems can be solved by the following means, and have reached the present invention. That is, the present invention has the following configuration.
(1) When the total amount of all the acid components and all glycol components of the polyester resin is 100 mol%, 60 to 85 mol% terephthalic acid, 10 to 20 mol% isophthalic acid, 1,4- 5 to 10 mol% of cyclohexanedicarboxylic acid, 80 to 30 mol% of 1,4-butanediol as a glycol component, 20 to 70 mol% of triethylene glycol and / or diethylene glycol, and a melting point of 80 to A crystalline polyester resin having a glass transition temperature of -20 to 30 ° C. at 160 ° C.
(2) The crystal according to (1), wherein the total mass of triethylene glycol residue, diethylene glycol residue and 1,4-cyclohexanedicarboxylic acid residue occupies 15 to 40% by mass of the polyester resin. Polyester resin.
(3) The crystalline polyester resin has a solid content concentration of 5% by mass in at least one mixed solvent in which the total concentration of toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate is 20% by mass or more of the total mixed solvent. It is soluble, and the solution viscosity measured by a B-type rotational viscometer measured at 25 ° C. when stored at 25 ° C. for 3 days is not more than twice that immediately after dissolution (1 Crystalline polyester resin as described in).
(4) The crystalline polyester resin according to (1) is contained, including at least one solvent selected from toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate as a solvent, and a total of the five solvents Occupies 20% by mass or more of the total solvent.
(5) The adhesive composition according to (4) , comprising at least one of a flame retardant, a pigment, and an antiblocking agent.
Details of the present invention will be described below.

According to the present invention, it is excellent in adhesiveness to various plastic films, wood, paper, leather, metal, etc., and particularly in flexible flat cable applications used for wiring of electric and electronic devices, polyester film, tin-plated copper and A crystalline polyester resin having excellent adhesion and heat resistance to an electrolytic copper foil, excellent solubility in general-purpose solvents, and having a good storage stability in a dissolved material, and an adhesive composition using the same Things can be obtained.

As an acid component constituting the crystalline polyester resin of the present invention, terephthalic acid is 60 to 100 mol%, preferably 65 to 95 mol%, more preferably 70 to 90 mol%, and further preferably 75 to 85 mol%. . If it is less than 60 mol%, the crystallinity and mechanical strength of the resin are insufficient, and the adhesiveness and heat resistance tend to decrease.

The acid component constituting the crystalline polyester resin of the present invention preferably contains an alicyclic dibasic acid component in addition to terephthalic acid. By including the alicyclic dibasic acid, the polyester resin can enhance solubility in a solvent while maintaining appropriate crystallinity. Examples of the alicyclic dibasic acid include 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, and dimer acid. It is done. Among these, 1,4-cyclohexanedicarboxylic acid is preferable. The content of 1,4-cyclohexanedicarboxylic acid in the total acid component is 5 to 30 mol%, preferably 10 to 20 mol%. If it exceeds 30 mol%, the mechanical strength of the resin will be insufficient, and the adhesiveness and heat resistance will decrease, and if it is less than 5 mol%, the solubility in the solvent and the storage stability will tend to decrease. It is in.

  In addition, the crystalline polyester resin of the present invention can be appropriately copolymerized with the dibasic acid component shown below within the aforementioned range. As aromatic dibasic acids, isophthalic acid, orthophthalic acid, 1,5-naphthalic acid, 2,6-naphthalic acid, 4,4′-diphenyldicarboxylic acid, 2,2′-diphenyldicarboxylic acid, 4,4 ′ Examples of the aliphatic dibasic acid such as -diphenyl ether dicarboxylic acid include adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, octadecanedioic acid and the like.

  Furthermore, the glycol component constituting the crystalline polyester resin of the present invention is characterized by containing triethylene glycol and / or diethylene glycol. By containing these glycols, the balance between crystallinity and solvent solubility can be highly controlled. The total content of triethylene glycol and diethylene glycol in all glycol components of the crystalline polyester resin of the present invention is 20 mol% or more and 70 mol% or less. It is preferably 25 mol% or more, more preferably 30 mol% or more. Moreover, it is preferable that it is 60 mol% or less, More preferably, it is 50 mol% or less. When the amount is more than 70 mol%, the crystallinity of the resin tends to decrease, and the adhesiveness and heat resistance tend to decrease. When the amount is less than 20 mol%, the resin has a high crystallinity and is soluble in a solvent. Storage stability tends to decrease. In the present invention, “the content of triethylene glycol or / and diethylene glycol in the total glycol component is 20 mol% or more and 70 mol% or less.” Means that the total content of triethylene glycol and diethylene glycol is the total glycol. This means that it is 20 mol% or more and 70 mol% or less of the component, and when either one of triethylene glycol and diethylene glycol is not contained, the content of only the other one is 20 mol% or more and 70 mol% or less. Refers to that.

  As a glycol component constituting the crystalline polyester resin of the present invention, 1,4-butanediol is contained. By containing 1,4-butanediol, crystallinity and melting point are increased, and heat resistance can be improved. The 1,4-butanediol content in the total glycol component is 30 to 80 mol%, preferably 40 to 75 mol%, more preferably 50 to 70 mol%. If it is more than 80 mol%, the melting point and crystallinity of the resin are high, and the solubility in a solvent and storage stability are reduced. If it is less than 30 mol%, the crystallinity of the resin is reduced, and the adhesiveness, Heat resistance tends to decrease.

  The glycol component constituting the crystalline polyester resin of the present invention is basically composed of diethylene glycol or / and triethylene glycol and 1,4-butanediol. However, other glycol components can be copolymerized as long as the effects of the crystalline polyester resin of the present invention are not impaired. Examples of other copolymerizable glycol components include aliphatic glycols such as ethylene glycol, alicyclic glycols such as 1,4-cyclohexanedimethanol, and aromatic glycols such as ethylene oxide adducts of bisphenol A. . The content of the other glycol component is preferably 20 mol% or less, more preferably 10 mol% or less, based on the total glycol component.

  Regarding the constituent components of the crystalline polyester resin of the present invention, increasing the copolymerization amount of diethylene glycol or / and triethylene glycol and 1,4-cyclohexanedicarboxylic acid reduces the crystallinity of the polyester resin and reduces the cohesive force. And has the effect of improving solubility. When the total amount of diethylene glycol and triethylene glycol is small, it is necessary to increase 1,4-cyclohexanedicarboxylic acid, and conversely, when the amount of 1,4-cyclohexanedicarboxylic acid is small, the total of diethylene glycol and triethylene glycol It is necessary to increase the amount. Specifically, the total amount of diethylene glycol residue, triethylene glycol residue and 1,4-cyclohexanedicarboxylic acid residue in the crystalline polyester resin preferably accounts for 10 to 40% by mass of the crystalline polyester resin. If it is 15-35 mass%, it is more preferable.

The crystallinity of the polyester resin of the present invention means that a melting point peak is observed by differential scanning calorimetry (temperature increase rate: 20 ° C./min). Melting | fusing point is 80-160 degreeC, Preferably it is 90-150 degreeC, More preferably, it is 100-140 degreeC, More preferably, it is 110-130 degreeC. When the melting point of the resin is less than 80 ° C., the solubility in the solvent is very good, but the heat resistance tends to decrease, and when the melting point of the resin exceeds 160 ° C., the heat resistance is improved. Solubility in water and storage stability tend to be greatly reduced. However, the solubility in a solvent differs depending on the energy for melting the crystalline state, that is, the degree of crystallinity, even for resins having the same melting point.

  The glass transition temperature of the polyester resin of the present invention is -20 ° C to 30 ° C, preferably -15 ° C to 20 ° C, more preferably -10 ° C to 10 ° C. When the glass transition temperature is less than −20 ° C., the elastic modulus at a high temperature is lowered, and the adhesive force may be insufficient. For example, when it is used as an adhesive for automobile parts and home appliances, the adhesive strength may decrease in a high temperature environment in summer, and it may be difficult to sufficiently bond the parts to each other. Furthermore, resin blocking may easily occur, and it may be difficult to handle a substrate such as a film after applying an adhesive. On the other hand, if the glass transition temperature exceeds 30 ° C., the modulus of elasticity near room temperature becomes high, and the resin itself is too stiff so that adhesion to the adherend may not be exhibited.

  The solvent used in the adhesive composition of the present invention preferably contains at least one solvent selected from toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate, and the five solvents are all included. More preferably, it is 20% by mass or more in the solvent. The five types of solvents are industrial general-purpose solvents having a boiling point of 70 to 140 ° C., and are excellent in cost and workability. If necessary, cyclohexanone, tetrahydrofuran, dimethylformamide, dioxane, dioxolane, phenol, benzyl alcohol, acetate-based organic solvents, and cellosolve-based organic solvents (the cyclohexanone and below, cellsolve-based organic solvents; Can be used in combination. When a solvent such as cyclohexanone is used in combination, the storage stability of the adhesive composition can be improved as compared with the case where only the above five solvents are used, but the solvent price is high and the boiling point of the solvent is high. There is one or a plurality of problems that it is likely to remain in the film and the solvent is highly harmful, and it is not preferred for industrial use. Chlorinated solvents such as dichloromethane, dichloroethane, trichloromethane, and trichloroethane are also effective in greatly improving the dissolution stability and can be used alone or in combination with the above-mentioned five solvents. In some cases, it may be difficult to actually use.

In the present invention, the crystalline polyester is dissolved at a solid content concentration of 5 mass% in at least one mixed solvent in which the total concentration of toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate is 20 mass% or more of the total mixed solvent. It is possible that the solution viscosity (measured at 25 ° C.) measured with a B-type viscometer when the dissolved material is stored at 25 ° C. for 3 days is preferably 2 times or less immediately after dissolution.

The crystalline polyester of the present invention is solvent-soluble. Solvent-soluble in the present invention means that when the mass of all solvents is 100% by mass, 5% by mass of toluene is dissolved in a mixed solvent of 20% by mass of toluene and 80% by mass of dichloromethane at 25 ° C. It indicates that the solution viscosity measured with a B-type rotational viscometer measured at 25 ° C. when stored at 25 ° C. for 3 days is 2 times or less immediately after dissolution. Practically, it is desired that 5% by mass or more, more preferably 10% by mass or more, further preferably 15% by mass or more, particularly preferably 20% by mass or more, and most preferably 25% by mass are dissolved in the aforementioned solvent.

  Here, in the adhesive composition of the present invention, the blending ratio of the polyester resin and the solvent is 5/95 to 40/60% by mass, preferably 10/90 to 35/65% by mass, more preferably 15 / It is 85-30 / 70 mass%. If the concentration of the polyester resin is greater than 40% by mass, the adhesive will have poor dissolution stability, and if it is less than 5% by mass, it is necessary to increase the number of times the adhesive is applied when increasing the thickness of the adhesive layer. As a result, work efficiency is poor and productivity is lowered.

  The reduced viscosity (unit dl / g) of the polyester resin of the present invention is 0.60 to 0.95, preferably 0.70 to 0.90, and more preferably 0.75 to 0.85. If the reduced viscosity is less than 0.60, the cohesive strength of the polyester resin may be low and the adhesive force may be reduced. If the reduced viscosity is more than 0.95, it may be hardly soluble in the solvent.

The polyester resin of the present invention thus obtained can be used in an adhesive composition by mixing various additives with the aforementioned solvent. As an additive, it is preferable to mix and use a flame retardant, a pigment, and an antiblocking agent. As flame retardants, brominated flame retardants such as decabromodiphenyl ether, bis (pentabromophenyl) ethane, tetrabromobisphenol A, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, triethyl phosphate, cresyl Diphenyl phosphate, xylenyl diphenyl phosphate, cresyl bis (2,6-xylenyl) phosphate, 2-ethylhexyl phosphate, dimethyl ethyl phosphate, resorcinol bis (diphenyl) phosphate, bisphenol A bis (diphenyl) phosphate, Bisphenol A bis (dicresyl) phosphate, diethyl-N, N-bis (2-hydroxyethyl) aminomethyl phosphate, phosphoric acid amide, organic phosphate Phosphorus flame retardants such as fin oxide and red phosphorus, ammonium polyphosphate, phosphazene, cyclophosphazene, triazine, melamine cyanurate, succinoguanamine, ethylene dimelamine, triguanamine, triazinyl cyanurate, melem, melam, tris (Β-cyanoethyl) isocyanurate, acetoguanamine, guanylmelamine sulfate, melem sulfate, melam sulfate, nitrogen flame retardants, potassium diphenylsulfone-3-sulfonate, aromatic sulfonimide metal salt, polystyrene sulfonate alkali metal salt, etc. Metal salt flame retardant, aluminum hydroxide, magnesium hydroxide, dolomite, hydrotalcite, barium hydroxide, basic magnesium carbonate, zirconium hydroxide, tin oxide and other hydrated metal compound flame retardants, silica, Aluminum oxide, iron oxide, titanium oxide, manganese oxide, magnesium oxide, zirconium oxide, zinc oxide, molybdenum oxide, cobalt oxide, bismuth oxide, chromium oxide, tin oxide, antimony oxide, nickel oxide, copper oxide, tungsten oxide, boric acid Inorganic flame retardants such as zinc, zinc metaborate, barium metaborate, zinc carbonate, magnesium carbonate, calcium carbonate, barium carbonate, zinc stannate, and silicon flame retardants such as silicone powder. Of these, brominated flame retardants such as bis (pentabromophenyl) ethane are particularly preferably used. Two or more of these flame retardants can be used in combination, and a combination of a brominated flame retardant such as bis (pentabromophenyl) ethane and an inorganic flame retardant such as antimony oxide is particularly preferable. As the pigment, titanium oxide, carbon black, or the like is used. Silica, calcium carbonate, talc and the like are used as the antiblocking agent, and silica is particularly preferable from the viewpoint of adhesiveness.

If necessary, the adhesive composition of the present invention may contain a silane coupling agent, a tackifier, a crystal nucleating agent, an ultraviolet absorber, an epoxy compound, an isocyanate compound, and the like.

In order to describe the present invention in more detail, examples are given below, but the present invention is not limited to the examples. In the examples, “parts” means parts by mass. In addition, the measured value described in the Example is measured by the following method.

Resin composition: The resin was dissolved in deuterated chloroform, and ¹ H-NMR analysis was performed using a nuclear magnetic resonance analyzer (NMR) Gemini-200 manufactured by Varian Inc., and the integral ratio was determined.

Melting point, glass transition temperature: Using a differential scanning calorimeter, 10 mg of a measurement sample is put in an aluminum pan, sealed with a lid, and using a differential scanning calorimeter (DSC) DSC-220 manufactured by Seiko Instruments Inc. It calculated | required by measuring with the temperature increase rate of 20 degrees C / min. The temperature showing the maximum value of the melting peak was taken as the melting point. Moreover, the temperature of the intersection of the extended line of the base line below a glass transition temperature and the tangent which shows the maximum inclination in a transition part was made into the glass transition temperature.

Number average molecular weight: Calculated from the results of GPC measurement using a gel filtration permeation chromatograph (GPC) 150c manufactured by Waters with tetrahydrofuran as the mobile phase at a column temperature of 30 ° C. and a flow rate of 1 ml / min. Measurements were obtained. However, Showa Denko Co., Ltd. shodex KF-802, 804, 806 was used for the column.

Acid value: 0.2 g of polyester was dissolved in 20 ml of chloroform, and titrated with a 0.1 N potassium hydroxide ethanol solution to obtain an equivalent (eq / 10 ⁶ g) per 10 ⁶ g of resin.

Reduced viscosity: 0.1 g of polyester was dissolved in 25 cc of a phenol / tetrachloroethane (mass ratio 6/4) mixed solvent and measured at 30 ° C. using an Ubbelohde viscosity tube to reduce the reduced viscosity η _sp / C (dl / g). Asked.

Storage stability: The polyester resin was heated and mixed as necessary so that the solid content concentration was 5%, and dissolved in a mixed solvent of toluene / dichloromethane = 20/80% by mass. The solution on the left was transferred to a 200 mL mayonnaise bottle, immersed in a thermostat adjusted to 25 ° C., and left to stand for 2 hours. Next, the solution viscosity was measured using a B-type rotational viscometer (manufactured by Tokyo Keiki Co., Ltd., EM type), and this was taken as the viscosity immediately after dissolution. The solution on the left was stored sealed in a dark place at 25 ° C. for 3 days, the solution viscosity was measured again using a B-type rotational viscometer, and the ratio to the viscosity immediately after dissolution was determined according to the following criteria to evaluate storage stability. .
The solution viscosity after 3 days is less than 1.2 times immediately after dissolution:
The solution viscosity after 3 days is 1.2 times to 2 times immediately after dissolution:
The solution viscosity after 3 days is more than twice that immediately after dissolution: x

<Synthesis example 1 of crystalline polyester resin>
In a reaction vessel equipped with a stirrer, a thermometer, and an outflow condenser, 199.2 parts of terephthalic acid, 24.9 parts of isophthalic acid, 25.8 parts of 1,4-cyclohexanedicarboxylic acid, 1,4-butanediol 135 parts, 159 parts of diethylene glycol, and 0.15 part of tetrabutyl titanate were added, and the temperature was gradually raised to 230 ° C. over 4 hours, and the esterification reaction was performed while removing distilled water out of the system. After completion of the esterification reaction, initial polymerization under reduced pressure was carried out to 10 mmHg over 30 minutes, the temperature was raised to 270 ° C., and the latter polymerization was carried out at 1 mmHg or less for 1.5 hours. In this way, a crystalline polyester resin synthesis example 1 was obtained. As a result of ¹ H-NMR analysis, the polyester resin of Synthesis Example 1 was found to have 80 mol% terephthalic acid, 10 mol% isophthalic acid, 10 mol% 1,4-cyclohexanedicarboxylic acid, 46 mol% 1,4-butanediol, diethylene glycol 54 It was a white crystalline resin having a composition of mol%, a reduced viscosity of 0.75 dl / g, a glass transition temperature of 14 ° C., a melting point of 127 ° C., and an acid value of 20 equivalents / 10 ⁶ g. The characteristic values of the crystalline polyester resin thus obtained are shown in Table 1.

<Preparation of Polyester Resin Solution in Synthesis Example 1>
In a reaction vessel equipped with a stirring blade, a thermometer, and a reflux condenser, 10 parts of the crystalline polyester resin obtained in Synthesis Example 1, 38 parts of toluene, and 152 parts of dichloromethane were charged, and the temperature was raised to 50 ° C. It completely dissolved over 3 hours to obtain a polyester resin solution. Table 1 shows the storage stability of the resin solution.

<Synthetic Examples 2, 6, 7, 9, 10 of Crystalline Polyester Resins , Reference Synthetic Examples 3-5, 8, Comparative Synthetic Example 1, Comparative Synthetic Examples 2 and 3 of Amorphous Polyester Resin>
In the same manner as in Synthetic Example 1, Synthetic Examples 2, 6, 7, 9, 10 for crystalline polyester resins , Reference Synthetic Examples 3 to 5, 8, Comparative Synthetic Example 1, Comparative Synthetic Example 2 for amorphous polyester resin, and 3 was synthesized. The characteristic values of the crystalline polyester resin and amorphous polyester resin thus obtained are shown in Table 1 or Table 2. BPE-20F represents an ethylene oxide adduct of bisphenol A manufactured by Sanyo Chemical Industries.

<Preparation of Resin Solutions of Polyester Resins in Synthesis Examples 2, 6, 7, 9, 10, Reference Synthesis Examples 3-5, 8, and Comparative Synthesis Examples 1-3>
In the same manner as in the case of the polyester resin of Synthesis Example 1, the polyester resins of Synthesis Examples 2, 6, 7, 9, 10, Reference Synthesis Examples 3 to 5, 8 and Comparative Synthesis Examples 1 to 3 are dissolved in a solvent, and polyester is prepared. A resin solution was obtained. Tables 1 and 2 show the storage stability of the crystalline polyester resin solution and the amorphous polyester resin solution thus obtained.

<Adhesive composition 1>
In a 100 ml glass bottle containing glass beads having a diameter of 2 mm, 333 parts of a crystalline polyester resin solution with a solid content adjusted to 30%, as in <Preparation of polyester resin resin solution of Synthesis Example 1> 50 parts of bis (pentabromophenyl) ethane (SAYTEX8010 manufactured by Albemarle), 36 parts of antimony trioxide, 10 parts of titanium oxide, and 4 parts of silica (Aerosil R972 manufactured by Nippon Aerosil Co., Ltd.) were charged in a shaker. Time dispersion was performed to obtain the intended adhesive composition 1.
Table 3 shows the composition of the adhesive composition 1 thus obtained.

<Adhesive composition 2, 6, 7, 9, 10, reference composition 3-5, 8, comparative composition 1-3>
In the same manner as in the adhesive composition 1, using the resins obtained in Synthesis Examples 2, 6, 7, 9, 10, Reference Synthesis Examples 3-5, 8, and Comparative Synthesis Examples 1-3 of the crystalline polyester resin, Additives were blended to obtain target adhesive compositions 2, 6, 7, 9, 10, reference compositions 3-5, 8, and comparative compositions 1-3. Table 3 shows the composition of the adhesive composition and the comparative composition thus obtained.

<Example 1>
The adhesive obtained with the adhesive composition 1 was evaluated according to the evaluation items as shown below. The evaluation results are shown in Table 3.

Adhesive strength: The adhesive composition obtained in the adhesive composition 1 was applied onto a 25 μm biaxially stretched PET film so that the thickness after drying was 30 μm, and dried at 120 ° C. for 10 minutes. . The adhesive composition-coated PET film thus obtained was laminated on the adhesive-coated surface and the glossy surface of the electrolytic copper foil using a roll laminator manufactured by Tester Sangyo Co., Ltd., laminating temperature 150 ° C., pressure 0.3 MPa, speed 1 m. Bonding was performed under the conditions of / min. The bonded product thus obtained was cut to a width of 1 cm, and a tensile test was carried out using a RTM100 manufactured by Toyo Baldwin Co., Ltd. at a pulling rate of 50 mm / min in an atmosphere of 25 ° C. Was measured.
As the electrolytic copper foil, USLPSE-18 μm manufactured by Nippon Electrolytic Co., Ltd. was used.
(Determination) A: 20 N / cm or more B: 10 N / cm or more and less than 20 N / cm Δ: 5 N / cm or more and less than 10 N / cm ×: less than 5 N / cm

Heat resistance: The adhesive composition obtained in the adhesive composition 1 was applied on a 25 μm biaxially stretched PET film so that the thickness after drying was 30 μm, and dried at 120 ° C. for 10 minutes. . Thus, the laminated body which apply | coated the adhesive composition obtained so that width of 0.8 mm and thickness 0.05mm may be ten tin plating copper wires, and the space | interval of a copper wire may become 1.0 mm width. In a state where a 50 μm biaxially stretched polypropylene film is overlaid as a release film on top of it, using a roll laminator manufactured by Tester Sangyo Co., Ltd., laminating temperature 150 ° C., pressure 0.3 MPa, speed 1 m / min. Bonding was performed under conditions. Thereafter, the polypropylene film was removed, a tin-plated copper wire was turned upward, a weight was placed so as to be 1 N / cm ^2, and heat treatment was performed at 80 ° C. for 72 hours. The depth of the sinking of the tin-plated copper wire of the sample heat-treated in this way into the adhesive layer was measured.
(Judgment) ◎: Less than 2 μm ○: 2 μm or more and less than 5 μm Δ: 5 μm or more and less than 10 μm ×: 10 μm or more

<Examples 2, 6, 7, 9, 10, Reference Examples 3-5, 8, and Comparative Examples 1-3>
Table 3 shows the results of evaluation of adhesive compositions 2, 6, 7, 9, 10, reference compositions 3-5, 8, and comparative compositions 1-3 in the same manner as adhesive composition 1. Shown in

Comparative composition 1 has excellent heat resistance, but is inferior in storage solubility and storage stability. The crystalline polyester resin contained in the comparative composition 1 has a high melting point of 198 ° C. and is outside the scope of the claims.
Comparative composition 2 has good adhesion and storage stability but is inferior in heat resistance. The polyester resin contained in the comparative composition 2 does not use 1,4-butanediol, is amorphous, and is outside the scope of the claims.
Comparative composition 3 is inferior in adhesiveness and heat resistance. The polyester resin contained in the comparative composition 3 does not use 1,4-butanediol, triethylene glycol, or diethylene glycol, is amorphous, has a high glass transition temperature, and is outside the scope of the claims.

  The crystalline polyester resin and adhesive composition obtained in the present invention have superior heat resistance and superior adhesion to polyester film, tin-plated copper and electrolytic copper foil as compared with the prior art, and can be used as a general-purpose solvent. It exhibits excellent solubility and good storage stability. For this reason, it is useful as an adhesive composition, and exhibits excellent performance particularly in flexible flat cable applications used for wiring of electric and electronic devices.

Claims (4)

When the total amount of all acid components and all glycol components of the polyester resin is 100 mol%, terephthalic acid is 60 to 85 mol%, isophthalic acid is 10 to 20 mol%, and 1,4-cyclohexanedicarboxylic acid as the acid component. the containing 5-10 mol%, and the glycol component 1,4-butanediol - Le to 72-46 mol%, triethylene glycol and / or diethylene glycol containing from 28 to 54 mol%, a melting point of 80 to 160 ° C., An adhesive comprising a crystalline polyester resin having a glass transition temperature of -20 to 30 ° C. and a solvent, and containing at least one of bis ( pentabromophenyl ) ethane, antimony trioxide, titanium oxide, and silica. Agent composition . The adhesive composition according to claim 1, wherein the total mass of the masses of triethylene glycol residue, diethylene glycol residue and 1,4-cyclohexanedicarboxylic acid residue occupies 15 to 40% by mass of the polyester resin. Thing . The crystalline polyester resin can be dissolved in at least one mixed solvent in which the total concentration of toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate is 20% by mass or more of the total mixed solvent at a solid content concentration of 5% by mass. The solution viscosity measured by a B-type rotational viscometer measured at 25 ° C. when the dissolved material is stored at 25 ° C. for 3 days is 2 times or less immediately after dissolution. Adhesive composition . The solvent contains at least one solvent selected from toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate, and the total of the five solvents occupies 20% by mass or more of the total solvent. The adhesive composition according to claim 1 .