TW201031728A - Adhesive composition - Google Patents

Abstract

The issue of this invention is to provide an adhesive composition which has excellent adhesive strength, heat resistance and workability without using halogen, and more particularly to an adhesive composition that is suitable for applications in electro-conductive adhesive agent which can be properly applied in connecting substrates. The solution means of this invention is to produce a composition containing resin components composed of A. 10 to 80 parts by weight of a polyamide elastomer, B. 10 to 80 parts by weight of a polyurethane elastomer, and C. 10 to 80 parts by weight of a styrene-isobutylene-styrene copolymer (with the total amount of A, B, and C being 100 parts by weight).

Description

201031728 VI. Description of the Invention: [Technical Advantages of the Invention] Field of the Invention The present invention relates to an adhesive composition excellent in adhesion strength, heat resistance, and workability, and more particularly to a composition suitable for application to a conductive adhesive. Adhesive composition. Background of the Invention A gas-butadiene-based conductive adhesive is used for adhesion of an electrode film of a touch panel to a connector, adhesion of various film substrates, and the like (for example, Patent Document 1). However, due to increased environmental and safety requirements in recent years, halogen-free is also strongly required for adhesives. In addition, the conventional chloroprene-based conductive adhesive does not necessarily satisfy the requirements in terms of adhesion strength, heat resistance, and workability depending on the application, particularly as an adhesive composition for substrate connection, and has heat resistance. Difficult to say that it is enough. Therefore, a halogen-free conductive adhesive which is excellent in adhesion strength, heat resistance, and workability is required, and in particular, the present invention is also applicable to materials having excellent characteristics as described above for substrate connection. [PRIOR ART DOCUMENT] [Patent Document 1] JP-A-2004-143219 SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION The present invention is based on the above needs, and aims to provide A kind of adhesive strength, materiality, and workability--all of them are excellent (four) money adhesive composition. The purpose of the towel is particularly to provide an adhesive composition suitable for use in a conductive adhesive used in the connection of a substrate. [Means for Solving the Problem] As a result of intensive research to solve the above problems, the present inventors have found that an adhesive having excellent adhesion strength and heat resistance can be obtained by using three kinds of thermoplastic elastomers having different polarities, and finally completed. this invention. That is, the adhesive composition of the present invention is composed of A. polyamine elastomer 10 to 80 wt%, B. polyaminophthalate elastomer 1 〇 8 〇, and C. stupid ethylene - The isobutylene-styrene copolymer is formed by a resin component having a weight fraction of 1 〇 to 8 〇 (but a total amount of a, B, and C is 1 〇〇 by weight). The above-mentioned adhesive domain towel-lipid component preferably has a phase separation structure in which the aforementioned B-polycarbamic acid (tetra)carboxylic acid and the aforementioned C. styrene-isobutylene-styrene copolymer are dispersed in the aforementioned A. polyamine elastomer. The adhesive composition of the present invention can be made to further contain a conductive filler. [Effect of the Invention] The adhesive composition of the present invention not only satisfies the requirement of dentate-free, but also has excellent adhesion strength, heat recovery, workability, and the like, which is superior to a conventional chloroprene adhesive, and is suitable for application to an electrode of a touch panel. Conductive adhesive used in the connection of the film to the connector and the connection of various film substrates. BRIEF DESCRIPTION OF THE DRAWINGS 201031728 [Fig. 1] is a plan view showing a flexible printed circuit board (hereinafter sometimes abbreviated as FPC) 1 used in an embodiment of the present invention. Fig. 2 is a plan view showing a polymer thick film circuit sheet (hereinafter sometimes abbreviated as PTF) substrate 2 used in the embodiment of the present invention. [Fig. 3] is a plan view showing the connection position of the FPcmRTT substrate 2. [Fig. 4] is a perspective view and a cross-sectional view showing a test method of 9-inch peel strength. [Fig. 5] is a plan view showing a method of measuring the connection resistance. t embodiment; J for carrying out the invention. The adhesive composition of the present invention will be described in detail below. The adhesive composition of the present invention contains a thermoplastic amine elastomer (hereinafter sometimes abbreviated as a polyamide elastomer or TPAE) or a polyurethane thermoplastic elastomer (hereinafter, abbreviated as follows) Polyurethane elastomer or tpu) ' and benzene (tetra) polymer (& both ends are polystyrene chains, which are fully saturated copolymers formed by polyisobutylene chains. Hereinafter, sometimes abbreviated as SIBS) The resin component formed. Here, "elastomer" means a synthetic rubber material having thermoplasticity. In particular, in the present invention, a hard segment having a large cohesive force and a flexible soft segment are used. The polyamidoline-based thermoplastic elastomer (TPAE) used in the present invention has a polyether or polyester chain which has a high melting point (Tm) polyamine as a hard segment and a low melting point or a low glass transition temperature (Tg), respectively. As the structure of the soft segment. 11&gt; Eight hard corners can be made of nylon 12 or nylon 6, etc. Soft segments are both available for 5 201031728 with aliphatic polyether or aliphatic polyester. More specifically, it can be dissolved in an amine solvent or a ketone solvent. The amine solvent may, for example, be diethylamine, triethylamine, propylamine, isopropylamine, dipropylamine, diisopropylamine, butylamine, isobutylamine, sec-butylamine, tert-butylamine, dibutylamine or diisoamine. Butylamine, tributylamine, pentylamine, diamylamine, triamylamine, 2-ethylhexylamine, allylamine, aniline, N-methylaniline, ethylenediamine, propylenediamine, diethylenetriamine, guanidine Indoleamine, N-methylformamide, N,N-didecylguanamine, hydrazine, hydrazine-diethylguanamine, acetamidine, N-mercaptoacetamide, N,N-di Methylacetamide, N-mercaptopropionamide, 2-pyrrolidone, N-methylpyrrolidone, ε-caprolactone, urethane, etc. The ketone solvent may, for example, be acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, methyl isobutyl ketone, 2-heptanone, 4-heptanone, diisobutyl ketone or acetone acetone. , isopropylideneacetone, phorbolone, isophorone, cyclohexanone, nonylcyclohexanone, and the like. For the commercially available product, for example, a ruthenium series (solvent solubility grade, polyether ester guanamine type, polyester guanamine type) manufactured by Fuji Chemical Industry Co., Ltd. can be used. Among them, ΤΡΑΕ-12, ΤΡΑΕ-31, ΤΡΑΕ-32, ΤΡΑΕ-617, ΤΡΑΕ-Η471Η are preferred. The polyurethane thermoplastic elastomer (TPU) is composed of a polyurethane hard segment and a polyester or polyether soft segment, and has a structure in which an isocyanate and a polyhydroxide are bonded via a urethane bond. The polyester-based polyol may, for example, be an adipate-based, polycaprolactone-based or polycarbonate-based polyhydric alcohol; and the polyether-based polyhydric alcohol may, for example, be polyoxytetramethylene glycol (PTMG). 201031728 The isocyanate may, for example, be diphenylmethane diisocyanate (MDI), hydrogenated MDI, isophorone diisocyanate (IPDI) or the like. For example, the Miractran (registered trademark) series manufactured by Nippon Polyurethane Industry Co., Ltd. can be used for the commercially available product. In particular, P390RSUP, R395SRNAT, P480RSUI, P485RSUI, P490RSUI, P890RSUI, P22MRNAT, P25MRNAT, P26MRNAT, P22SRNAT, and P26SRNAT can be used as appropriate. The SIBS used in the present invention is formed by a hard segment of styrene and a soft segment of isobutylene, and a triblock copolymer structure in which isobutylene and styrene are livingly polymerized is preferred. Since the SIBS has a good thermal stability because the main chain is saturated, it exerts an effect of greatly improving the heat aging resistance of the adhesive composition using the same. In the commercially available product, for example, the mixing ratio of シ7, 'SIBSTAR (registered trademark) 〇 the above polyamine elastomer, polyurethane elastomer' and SIBS manufactured by Kanaka Corporation can be used. When the total amount is 1 part by weight, the proportion of each component falls within the range of 10 to 80 parts by weight, and it is preferable that the ratio is in the range of 20 to 60 parts by weight, respectively. By setting the mixing amount of the polyamide elastomer in a range of from 1 Torr to 8 Torr, a product having good adhesion to a polyimide resin or a metal can be obtained. Further, by setting the mixing amount of the polyurethane elastomer to a range of 丨〇 8 to 8 Å, it is possible to obtain heat resistance, adhesion to metal, and thixotropic 'screen printing property. In addition, by setting the mixing amount of SIBS in the range of 1 〇 to 8 〇 by weight, a product having good adhesion and good heat with the polyethylene terephthalate resin or polyolefin resin 7 201031728 or metal can be obtained. . The above-mentioned three kinds of resin components are each formed into a polyamidamide elastomer having a polystyrene elastomer having a moderate polarity and a small styrene-isobutylene-styrene copolymer having a small polarity dispersed in the largest polarity. In the phase separation structure, an adhesive composition excellent in any of adhesion strength, heat resistance, and workability of the object of the present invention can be obtained. When a dispersion of the above three kinds of resins is obtained, if a kneader such as a planetary kneader is used, a solvent is added to the three kinds of resins, and the mixture is heated and dissolved. As the solvent, a nitrogen-based or guanamine-based solvent such as N-methylpyrrolidone, hexane, heptane, decane, toluene, diphenylbenzene, cyclohexane or solvent oil, or isophorone can be used. The amount of the solvent to be used is preferably in the range of 10 to 50% by weight based on the solid content of the adhesive composition. If the solid content concentration is less than 10% by weight, the coating thickness cannot be ensured, and if it exceeds 50% by weight, the viscosity is too high and printing becomes difficult. In addition, the relationship with the resin component is such that the nitrogen-based or guanamine-based solvent and the ketone-based solvent are each in an amount of 0 to 375 parts by weight, and the hydrocarbon-based solvent is in the range of 0 to 125 parts by weight, based on 100 parts by weight of the resin component. It is better. To the adhesive composition of the present invention, conductive particles such as metal powder may be added to impart anisotropic conductivity. Examples of the conductive particles include metal powders such as copper, silver, lead, zinc, iron, and nickel, or particles of nickel, gold, silver, copper, and the like, such as inorganic powders such as metal powders or plastic powders or glass powders. . 201031728 The shape of the conductive particles is not particularly limited, and any particles such as a sphere, a scale, a potato, a needle, or a filament can be used. The size is preferably in the range of an average particle diameter of 1 to 50 μm. The amount of the conductive particles to be mixed depends on the use of the adhesive composition, but is usually in the range of 丨 to the weight of the resin component. The adhesive composition of the present invention may further add other components which will be used in the adhesive composition towel, that is, an viscosifier &amp; coffee, a stabilizer, an antioxidant, a filler, an enhancer, Pigments, defoamers, etc. EXAMPLES Examples of the invention are shown below, but the invention is not limited by the following examples. [Examples 1 to 6 and Comparative Examples 1 to 4] The three kinds of resin components shown in Table 1 were each mixed at a ratio (weight ratio, converted into a resin solid content) shown in the table, and dispersed. The dispersion was carried out by a planetary kneader at a temperature of 85 C and a number of revolutions of 50 rpm for 6 hours. To the resin component, 100 parts by weight (calculated as a solid component), a cerium component was added and mixed to prepare an adhesive composition. Conductive particles: metal powder (Ni powder, average particle size 35μπι) 55 heavy solvent: dimethylformamide (DMF) 180 parts by weight cyclohexanone 80 parts by weight toluene 45 parts by weight filler (talc, average particle size 4~5μηι) 50 parts by weight 9 201031728 Adhesive agent (PenselD_125, manufactured by Arakawa Chemical Co., Ltd.) 3 〇 Weights · Female Pharmacy (manufactured by Ciba Specialty Chemicals, IRGANOX (Note) 1010) 1.3 Weight With respect to the obtained adhesive composition, the 9-degree peel strength, the connection resistance, and the aging resistance were measured, and the printing workability and the press workability were evaluated. For the test sample, the measurement and evaluation methods are as follows. The results are shown in Table i. The sample for the test of the 90-degree peeling strength, the connection resistance, and the aging resistance is the flexible printed circuit board 1 (hereinafter abbreviated as FPC) which is shown in the following table, and is shown in the second. Figure polymer thick film road # 〇 (hereinafter sometimes abbreviated as PTF) substrate 2 ' as shown in Figure 3, with the adhesive composition 3 'pressed at a pressing temperature, pressure 3 〇 kgf / cm 2 for 15 seconds The film thickness when the connection was made to dry was 2 〇 ± 5 μιη. <FPC: ΝΙΚΚΑΝIndustry Co., Ltd.> Composition. Polyaniline 25μηι/铜簿Ι8μηι Electrode plating: Ni3p/Au〇.%m Pitch: 3 mm Electrode width (a): 10 mm ® <PTF substrate> Polymerization Toray Polyethylene Terephthalate (pET) 188μιη Silver Glue: About ΙΟμιη * Coating resist pitch on silver paste: 3mm <90 degree peel strength> As shown in Figure 4 It is shown that the tensile tester (for redundancy, ud. 10 201031728 PT-200N) was peeled at a tensile speed of 100 mm/min and a peeling direction of 90 degrees, and the maximum value at the time of breaking was measured. <Connection resistance> As shown in Fig. 5, the low resistance meter (11100 system, DC type 3227 111-〇11111 twisted 63161·) was used to measure ab and bc, respectively, between the FPC end of the FPC/PTF test sample. The connection resistance between cd and cd is calculated as the average value. <Aging resistance> After maintaining at 80 ° C for 1,000 hours, the 90-degree peel strength was measured and evaluated on the following basis: 〇: 5 N/cm or more, Δ: 3 N/cm or more, and X: less than 3 N/cm 〈 Printing workability> Printing was carried out by using a 80-mesh screen (Tetoron (registered trademark)) to maintain a dry film thickness (pBH20 ° C '15 minutes during drying) at 20 ± 5 μm. By visual observation, the presence or absence of wire drawing, plate peeling, foaming, and bleeding between the screen and the printed matter was observed and evaluated according to the following criteria: 〇: good workability, △: ordinary, poor 〈 [pressing workability] using a constant heater type press (manufactured by Asahi Kasei Co., Ltd., HBM-10) was rolled at a pressing temperature of 130 to 140 ° C and a pressure of 30 kgf/cm 2 for 15 seconds. The resin flow and voids were visually observed and evaluated by the following criteria:印刷. Good printing workability, △: ordinary, χ [ [Comparative Example 5] The same treatment as described in the above 11 201031728 except that the chloroprene-based composition was used as the adhesive composition, and the 90-degree peel strength and the connection resistance were measured. The anti-aging property was measured, and the printing workability and the press workability were evaluated. [Table 1] Lean application Comparative Example 1 2 3 4 5 6 1 2 1 4 &lt; Polyamide elastomer 43 56 ———. 38 ~~ — Bu 80 30 39 η Λ (\ 聚 Polyurethane Elastomer 40 24 h---- 20 / 11 οΖ _10_ 60 22 52 Q 83 SIBS 17 20 42, Ό J 10 10 39 41 57 6 15 _ Gas Butadiene Adhesive - - - 100 90 degree peeling strong ( N/cm) 7 1U 8 6 10 4 8 3 6 7 Connection resistance (Ω) 0.5 0.1 0.2 0.1 0.3 0.1 Λ勹 0.1 1 1.5 0.5 Anti-aging properties ----. 〇UZ 1 〇〇〇X Λ XX Λ Printing workability 〇〇〇〇〇 Δ Γ 〇〇 〇〇 pressing workability 〇〇 Δ UX Λ 〇 - - Δ Λ Δ ΖΛ [Industrial Applicability] Adhesive composition of the present invention It is especially suitable for the connection of various substrates, 'that is, the connection between the liquid crystal panel and the substrate, the connection of the membrane switch, the connection of the ELf light force', etc. [Simplified illustration of the drawing] [Fig. 1] shows the implementation of the present invention. The flexible printed circuit board used in the example (hereinafter sometimes abbreviated as FPC) 1 is a plan view. [Fig. 2] shows an embodiment of the present invention. A plan view of the polymer thick film sheet (hereinafter sometimes abbreviated as PTF) substrate 2. [Fig. 3] is a plan view showing the connection position of the FPC1 and the RTF substrate 2. [Fig. 4] shows 90 degrees. A perspective view and a cross-sectional view of the test method for peel strength. [Fig. 5] is a plan view showing a method of measuring the connection resistance. 12 201031728

[Description of main component symbols] 1···Flexible printed circuit board (FPC) 2.. Polymer thick film (PTE) substrate 3.. Adhesive composition 13

Claims (1)

201031728 VII. Patent application scope: 1. An adhesive composition containing 10 to 80 parts by weight of / A. Polyamide elastomer, "B. Polyurethane elastomer 10 to 80 parts by weight, and C A styrene-isobutylene-styrene copolymer is formed by a resin component having a composition of 10 to 80 parts by weight (but the total amount of A, B, and C is 100 parts by weight). 2. The adhesive composition as recited in claim 1 And the resin component comprises a phase separation structure in which the B. polyurethane elastomer and the C. styrene-isobutylene-styrene copolymer are dispersed in the A. polyamine elastomer. 3. The adhesive composition according to the first or second aspect of the patent application, further comprising a conductive filler.