TWI496863B - Conductive adhesive composition and conductive film - Google Patents

Description

Conductive adhesive composition and conductive adhesive film Field of invention

The present invention relates to an adhesive composition excellent in adhesion strength, long-term reliability, workability, and the like, and particularly relates to an adhesive composition suitable for use in an anisotropic conductive paste or a conductive adhesive film, and This is followed by a film.

Background of the invention

Heretofore, an anisotropic conductive paste has been used for connection between a signal pull-out circuit of a touch panel and a flexible printed circuit board. The problem of the anisotropic conductive paste has been to improve the uniformity of the film thickness. Recently, as the electrostatic capacitance type increases, the connection to the portion which is further finely pitched is also required.

The conventional anisotropic conductive paste is generally in the form of a chloroprene (for example, Patent Document 1). This form refers to the dryness of the touch, and although it is a short period of time, it has the advantage of being preserved at room temperature.

However, since environmental requirements or safety requirements have increased in recent years, it is strongly desired that the adhesive is also halogen-free. Further, depending on the use, the conventional chloroprene-based paste may not be satisfactory in terms of adhesion strength, long-term reliability, or workability, and particularly, when it is used as an adhesive composition for connection of a substrate, Long-term reliability cannot be considered sufficient.

Therefore, the present state of the art is to provide a halogen-free anisotropic conductive paste which is excellent in the following strength, long-term reliability, and workability, and is particularly suitable for use as a connector of the above substrate.

Moreover, the adhesive composition can be printed on the FPC used in the conventional resistive touch panel, and after printing and drying, it is crimped to the touch panel, however, in the electrostatic capacitive touch panel, due to the parts It is installed in the FPC. Therefore, it is difficult to print the paste. It is imperative to develop an anisotropic conductive film that replaces the conventional paste.

The anisotropic conductive film is, for example, a thermosetting resin such as a blend of an acrylic rubber and an epoxy resin, and has been used as a terminal product of a liquid crystal display. However, such products have problems in that they cannot be stored at room temperature, or have poor pluggability due to stickiness, and are expensive compared to conventional materials for touch panels.

Advanced technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2004-143219

The present invention has been made in view of the foregoing, and an object of the present invention is to provide an adhesive composition which is a halogen-free adhesive composition excellent in strength, long-term reliability, and workability, and is suitable for use in a substrate. In the connected anisotropic conductive paste.

Further, an object of the present invention is to provide an adhesive film which is suitable for use in a case where printing of a paste is difficult, and can be stored at room temperature, and is excellent in insertability by controlling viscosity, and is also cost-effective. It is beneficial.

As a result of intensive studies to solve the above problems, the inventors have found that the following adhesive composition can solve the above problems, and the present invention can be accomplished by adding a specific olefin resin to a specific polyetheresteramine as a substrate, and then, as needed It is composed of a urethane resin, a polyester resin, an acrylic resin or an epoxy resin.

That is, the adhesive composition of the present invention is prepared in an amount of from 1 part by weight to 300 parts by weight based on 100 parts by weight of the polyether ester amide (but is a resin solid, the same applies hereinafter). One or two or more kinds of the isobutylene-styrene-based olefin elastomer, the styrene-ethylene-butylene-styrene-based olefin elastomer, and the maleic anhydride-modified ones.

In the above-mentioned adhesive composition of the present invention, the urethane elastomer may be further contained, and the content thereof is preferably urethane based on 100 parts by weight of the polyether phthalamide. The elastomer is 10 parts by weight to 100 parts by weight.

In the above-mentioned adhesive composition of the present invention, or may further contain a polyester resin, the content thereof is preferably 1 part by weight to 100 parts by weight based on 100 parts by weight of the polyether ester decylamine. Parts by weight.

Further, in the above-mentioned adhesive composition of the present invention, an acrylic resin may be further contained, and the content thereof is preferably 1 part by weight to 100 parts by weight based on 100 parts by weight of the polyether ester guanamine. Parts by weight.

Further, in the adhesive composition of the present invention, the urethane elastomer, the polyester resin or the acrylic resin may be replaced, or together with the aforementioned urethane elastomer, polyester resin or acrylic resin. The epoxy resin is contained in an amount of 5 parts by weight to 50 parts by weight based on 100 parts by weight of the polyether ester amide.

Further, the adhesive composition of the present invention may further contain conductive particles.

The adhesive film of the present invention is composed of the above-described adhesive composition of the present invention.

The adhesive composition of the present invention not only satisfies the requirement of halogen-free, but also has superior strength, long-term reliability, workability, and the like than a conventional chloroprene-based adhesive, and is suitable for application to a signal applied to a touch panel. In an anisotropic conductive paste such as a connection between a circuit and a flexible printed circuit board.

The film obtained by using the above-described adhesive composition of the present invention can be stored at room temperature, and is excellent in insertability and is also advantageous in terms of cost.

Simple illustration

Fig. 1 is a plan view showing a flexible printed circuit board (hereinafter, abbreviated as FPC) 1 used in an embodiment of the present invention.

Fig. 2 is a plan view showing a thick film of a polymer (hereinafter sometimes abbreviated as PTF) used in the embodiment of the present invention.

Fig. 3 is a plan view showing the connection position of the aforementioned FPC1 and the PTF substrate 2.

Fig. 4 is a perspective view and a cross-sectional view showing a test method of 90-degree peel strength.

Fig. 5 is a plan view showing a method of measuring the connection resistance.

Form for implementing the invention

Hereinafter, the adhesive composition of the present invention will be described in detail.

The polyether ester decylamine (hereinafter, abbreviated as PEEA) used in the present invention has a melting point of 80 ° C to 135 ° C and a melt index of 5 g/10 min to 100 g/10 min (190 ° C, 21.18 N). Polyamine elastomer, and is preferably soluble in solvents. In the past, it has been difficult to film an elastomer. However, by using a solvent-soluble polyether ester decylamine, film formation becomes easy.

When the polyetheresteramine meets the above various conditions, the blending of the olefin resin or the urethane resin is easy, and it is easily prepared into a form of a solution-like adhesive or a coating. Since these systems form a thixotropic ratio (but the measured viscosity ratio (viscosity at 2 rpm / viscosity at 20 rpm) by using the viscometer PVB-10 manufactured by Toki Sangyo Co., Ltd.) is a liquid of 2.0 to 6.0, It will constitute excellent printability (release, sticky silk).

As used herein, "elastomer" means a synthetic rubber material having thermoplasticity. Among them, those having the following structure, that is, a hard segment having a large cohesive force and a soft segment having flexibility are preferably used. The polyether ester guanamine has a structure in which a polytheneamine having a high melting point (Tm) is formed into a hard segment, and a polyether or polyester chain having a low melting point or a low glass transition point (Tg) is formed into a soft chain. Paragraph. The hard segment of PEEA uses nylon 12 or nylon 6, and the soft segment uses both an aliphatic polyether or an aliphatic polyester.

As described above, PEEA is those which are soluble in a solvent, and more specifically, are soluble in an amine solvent, an alcohol solvent or a ketone solvent.

Examples of the amine solvent include diethylamine, triethylamine, propylamine, isopropylamine, dipropylamine, diisopropylamine, butylamine, isobutylamine, sec-butylamine, tert-butylamine, dibutylamine, and diisoamine. Butylamine, tributylamine, pentylamine, diamylamine, triamylamine, 2-ethylhexylamine, allylamine, aniline, N-methylaniline, ethylenediamine, propylenediamine, diethylenetriamine, Formamide, N-methylformamide, N,N-dimethylformamide, N,N-diethylformamide, acetamide, N-methylacetamide, N,N- Dimethylacetamide, N-methylpropionamide, 2-pyrrolidone, N-methylpyrrolidone, ε-caprolactam, urethane, and the like.

Examples of the alcohol solvent include methanol, ethanol, isopropanol (IPA), and benzyl alcohol.

Examples of the ketone solvent include acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, methyl isobutyl ketone, 2-heptanone, 4-heptanone, and diisobutylene. Ketone, acetonylacetone, isopropylideneacetone, phorbolone, isophorone, cyclohexanone, methylcyclohexanone, and the like.

As the polyether ester decylamine, those having a function of introducing -NH ₂ or -COOH or the like can also be suitably used. By introducing a functional group, the adhesion to metals, resins, and the like can be improved. In this case, it is preferably introduced to form an amine value of 20 or less and an acid value of 20 or less. When the functional group is excessively introduced, there is a problem that the peel strength or the connection reliability in a moisture-resistant environment is lowered.

PEEA is commercially available, for example, a TPAE series (solvent solubility grade, polyether ester guanamine form, polyester decyl form) manufactured by T&K TOKA Co., Ltd. can be used. Among them, TPAE-12, TPAE-31, TPAE-32, TPAE-617, TPAE-H471EP, TPAE-826, etc. of the TPAE series can be appropriately used depending on the use. These PEEAs may be used in combination of two or more kinds.

The styrene-isobutylene-styrene-based olefin elastomer used in the present invention (a fully saturated copolymer composed of a polystyrene chain at both ends and a polyisobutylene chain therebetween), hereinafter, abbreviated as SIBS The styrene is composed of styrene as a hard segment and isobutylene as a soft segment, and is preferably a triblock structure in which isobutylene and styrene are livingly polymerized. The main chain of the SIBS system is saturated, whereby it has excellent thermal stability and has an effect of greatly improving the heat aging resistance of the adhesive composition using the same. For example, SIBSTAR (registered trademark) manufactured by KANEKA Co., Ltd. can be used as a market maker.

Further, a styrene-ethylene-butylene-styrene-based olefin elastomer (a fully saturated copolymer composed of a polystyrene chain at both ends and an ethylene-butene chain therebetween) may be abbreviated as follows. SEBS.) is also composed of styrene as a hard segment and ethylene-butene as a soft segment, similarly to the aforementioned SIBS. Among the commercially available ones, H1052, H1053, H1051, H1041, M1943, M1911, M1913, MP10, P1500, etc. of TUFTEC (registered trademark) of Asahi Kasei Chemicals Co., Ltd. can be suitably used. When SEBS is used, as in the case of SIBS, the effect of improving the heat aging resistance of the adhesive composition which is achieved by the excellent thermal stability can be obtained, and in addition, since the gas permeability of SEBS is higher than that of SIBS, film formation is achieved. The solvent is well discharged and also has the advantages of a film that can achieve higher quality.

The olefin elastomer (SIBS or SEBS) can also be suitably used to be modified with maleic anhydride, whereby the adhesion to metals, resins, and the like can be improved.

The olefin elastomer (SIBS or SEBS or the maleic anhydride modified product) may be used alone or in combination of two or more.

The blending amount is preferably 1 part by weight to 300 parts by weight based on 100 parts by weight of the polyether ester decylamine, and blended with SIBS, SEBS or one of the maleic anhydride modified materials. Or two or more. By using an olefin elastomer in this range, adhesion to a polyethylene terephthalate resin or a polyolefin resin or a metal or long-term reliability can be improved.

In the present invention, a urethane elastomer (TPU) is further used, whereby the stability when the adhesive composition is used as a paste can be further improved. The urethane elastomer system is composed of a polyurethane hard segment and a polyester or polyether soft segment, and has a structure in which an isocyanate is bonded to a polyol by a urethane bond.

Examples of the polyester-based polyol include an adipate-based compound, a polycaprolactone-based compound, and a polycarbonate-based polyhydric alcohol. Examples of the polyether-based polyhydric alcohol include polyoxytetramethylene glycol (PTMG).

The isocyanate may, for example, be 4,4'-diphenylmethane diisocyanate (MDI), hydrogenated MDI, isophorone diisocyanate (IPDI) or the like.

For example, a MIRACTRAN (registered trademark) series manufactured by MIRACTRAN INDUSTRIAL CO., LTD. can be used. Among them, P390RSUP, P395SRNAT, P480RSUI, P485RSUI, P490RSUI, P890RSUA, P22MRNAT, P25MRNAT, P26MRNAT, P22SRNAT, P26SRNAT can be used as appropriate.

The urethane elastomer is preferably blended in a proportion of 10 parts by weight to 100 parts by weight based on 100 parts by weight of the polyether ester amide. When the content of the urethane elastomer is within this range, long-term reliability, adhesion to metal, touch modification, and screen printing properties can be improved.

Further, in the present invention, a polyester resin is further used, whereby the adhesion can be improved, and the workability when used as a paste can be improved. The polyester resin used in the present invention is preferably a functional group having a hydroxyl group, an epoxypropyl group or an amine group in the structure. Further, a crystalline polyester can also be used as the polyester resin.

As the polyester resin, for example, the FINEDIC (registered trademark) series manufactured by DIC Corporation can be used. Among them, M-8010, M-8020, M-8021, M-8023, M-8076, M-8100, M-8230, M-8240, M-8250, M-8830, M-8842 can be suitably used. M-8860, M-8630M-8961, M-8962, A-239-J, A-239-X, M-8420. As the crystalline polyester, a VYLON (registered trademark) series manufactured by Toyobo Co., Ltd. can be used. Among them, GA-6300, GA-3410, GM-913, GM-920, GA-6400, GA-5300, GA-5200, GM-900, and 30P can be suitably used. In addition, the NICHIGO POLYESTER (registered trademark) series manufactured by Nippon Synthetic Chemical Co., Ltd. may be used as the crystalline polyester, and SP-180, SR-100, VR-300, HR-200, and Z-1651ML may be suitably used. , Z-1606ML.

Further, in the present invention, an acrylic resin is further used, whereby the adhesion can be improved, and the workability when used as a paste can be improved. The acrylic resin is preferably a functional group having a hydroxyl group, a propylene group or an amine group in the structure. In the case of the market, for example, the FINEDIC (registered trademark) series manufactured by DIC Corporation can be used. Among them, A-247S, A-254, A-253, A-229-30, A-244-A, A-249, A-261, A-266, A-241, and A-251 can be suitably used.

Further, in the adhesive composition of the present invention, an epoxy resin may be further blended. The epoxy resin which can be suitably used may, for example, be based on bisphenol A, F, S or AF, and more specifically, for example, the product numbers 827 and 828 manufactured by Mitsubishi Chemical Corporation may be used. 828EL, 828XA, 834, 801N, 801PN, 802, 811, 813, 816A, 816C, 819, and the like.

ring

The oxygen resin is preferably blended in a proportion of 5 parts by weight to 50 parts by weight based on 100 parts by weight of the polyether ester guanamine. By using in this range, the film strength of the film obtained from the composition can be further enhanced.

The epoxy resin may be used instead of the aforementioned urethane elastomer, polyester resin or acrylic resin, or may be used together with the aforementioned urethane elastomer, polyester resin or acrylic resin.

The specific aspect of the adhesive composition composed of the above respective resin components is not particularly limited. For example, a medium-polarity urethane is dispersed in the polyether ester decylamine formed to be the most polar. When an elastomer, a polyester resin, an acrylic resin, and a phase-separation structure of a styrene-isobutylene-styrene copolymer having a small polarity are obtained, an adhesive which is excellent in adhesive strength and long-term reliability and workability as an object of the present invention can be obtained. Composition.

In order to obtain a dispersion in which the resin has been phase-separated as described above, for example, a kneader such as a planetary kneader can be used, and a solvent is added to the resin constituting the raw material to be heated, and dissolved and mixed.

In this case, a solvent such as a nitrogen-based or a guanamine-based solvent such as N-methylpyrrolidone; a hydrocarbon such as hexane, heptane, decane, toluene, xylene, cyclohexane, benzyl alcohol or solvent oil can be used. A solvent; a ketone solvent such as isophorone.

The amount of the solvent to be used is preferably in the range of 10% by weight to 50% by weight based on the resin solid content of the adhesive composition. When the resin solid content concentration is less than 10% by weight, the coating thickness cannot be ensured, and if it is more than 50% by weight, the viscosity becomes too high and printing is difficult. In addition, in the relationship with the resin component, the nitrogen-based or guanamine-based solvent and the ketone-based solvent are each preferably from 0 part by weight to 375 parts by weight, and the olefin-based solvent is preferably 0 part by weight, based on 100 parts by weight of the resin component. Parts are in the range of 125 parts by weight.

In the adhesive composition of the present invention, conductive particles such as metal powder can be added to form an electrically conductive paste having anisotropic conductivity.

Examples of the conductive particles are metal powders of copper, silver, lead, zinc, iron, nickel, etc.; or inorganic powders such as nickel, gold, silver, copper, etc., which are plated in such metal powders or plastic powders or glass powders. particle of.

The shape of the conductive particles is not particularly limited, and any of a true sphere, a scale, a potato shape, a needle shape, and an indefinite shape can be used. The size is preferably in the range of an average particle diameter of from 1 μm to 50 μm.

The content of the conductive particles varies depending on the use of the adhesive composition, but it is usually in the range of 1 part by weight to 100 parts by weight based on 100 parts by weight of the total resin solids in the adhesive composition. .

In the adhesive composition of the present invention, other components which are used in the adhesive composition, that is, an adhesive imparting agent (adhesive), a stabilizer, an antioxidant, a filler, and a reinforcing agent, may be further added as needed. Agents, pigments, defoamers, etc.

The adhesive film of the present invention can also be obtained from the adhesive composition of any of the foregoing inventions.

The adhesive film of the present invention is not only halogen-free, but also has the following features as compared with the adhesive film which has been used for the same purpose so far, that is, it is excellent in insertability due to controllability of viscosity, and is also advantageous in terms of cost.

The method of obtaining the adhesive film from the adhesive composition is not particularly limited, and the adhesive composition can be applied to a support such as a release paper by a coating method to form a predetermined thickness and dried. It is obtained by peeling off the release paper or the like. Specifically, an adhesive composition in which conductive particles are mixed as needed is dissolved in an amine solvent or a ketone solvent to obtain a desired viscosity, and is formed into a film by using a coater or the like. The thickness of the film can then be appropriately selected in accordance with the use, however, it is usually from 10 μm to 50 μm.

Further, when the adhesive film of the present invention is used, the desired adhesive strength can be obtained by pressure bonding at a temperature of 100 ° C to 160 ° C and a pressure of 1 MPa to 4 MPa for 5 seconds to 15 seconds.

According to the present invention, it is possible to solve the problem of paste printing which is difficult to mount after the components are mounted on the FPC in the recent electrostatic capacitance type touch panel, and the connection material can be crimped by transfer to a film form. Touch the panel.

Example

The embodiments of the present invention are shown below, however, the present invention is not limited to the following embodiments.

[Example 1 to Example 14, Comparative Example 1 to Comparative Example 5]

The following resin components shown in Table 1 were each blended and dispersed in a ratio (weight ratio, resin solid content) shown in the table. The dispersion was carried out by using a planetary kneader and kneading at a temperature of 85 ° C and a number of revolutions of 50 rpm for 6 hours.

Polyether ester decylamine: T&K TOKA Co., Ltd., TPAE-32

SIBS: manufactured by Zhong Yuan Co., Ltd., SIBSTAR 103T

SEBS: Asahi Kasei Chemicals Co., Ltd., TUFTEC M1911

Polyurethane elastomer: manufactured by Japan Mila Co., Ltd., MIRACTRAN P485RSUI

Epoxy resin: Mitsubishi Chemical Corporation, 828

Polyester resin: manufactured by Toyo Textile Co., Ltd., VYLON GA-5300

Acrylic resin: DIC Co., Ltd., FINEDIC A-254 The following components were added and mixed in 100 parts by weight of the resin component (solid content conversion) to prepare an adhesive composition.

Conductive particles: metal powder (Ni powder, average particle size 35 μm) 55 parts by weight

Solvent: dimethylformamide (DMF) 180 parts by weight

80 parts by weight of cyclohexanone

45 parts by weight of toluene

Filler (talc, average particle size 4 μm to 5 μm) 50 parts by weight

Adhesive imparting agent (PENSEL D-125, manufactured by Arakawa Chemical Industry Co., Ltd.) 30 parts by weight

Stabilizer (Ciba (CIBA) special chemical company, IRGANOX (registered trademark) 1010) 1.3 parts by weight

With respect to the obtained adhesive composition, 90-degree peel strength, connection resistance, and heat aging resistance were measured, and coating workability, printing workability, dry touch, and press workability were evaluated. Determination ‧ Evaluation method is as follows. Table 1 shows the results.

The test sample for 90-degree peel strength, connection resistance, and heat aging resistance is a flexible printed circuit board (FPC) 1 and 2 shown in Fig. 1 which are formed by the following specifications, via an adhesive composition layer. The polymer thick film (PTF) substrate 2 shown in the figure is connected as shown in Fig. 3 so that the end portion of the FPC is placed on one of the upper portions of the PTF substrate 2. Subsequently, in the first embodiment to the eighth embodiment, the eleventh embodiment, the twelfth embodiment, the comparative example 1, the comparative example 2, and the comparative example 4, the paste-like adhesive composition was applied to have a film thickness of 35 μm, and Example 9 was carried out. In Example 10, Example 13, Example 14, Comparative Example 3, and Comparative Example 5, the adhesive composition was previously formed to have a thickness of 35 μm, and the pressure was 130 ° C to 140 ° C and the pressure was 3 MPa. Pressing is carried out for 15 seconds. The film of Example 9 and the like was formed from the above-mentioned adhesive composition at a drying temperature of 110 ° C and a linear velocity of 10 m / min using a coating machine (manufactured by Inoue Metal Industries Co., Ltd., CED coater).

<FPC: Nikon (NIKKAN) Industrial Co., Ltd.>

Construction: Polyimine 25μm / copper foil 18μm

Electrode plating: Ni 3μm/Au 0.3μm

Spacing: 3mm

Electrode width (a): 10mm

<PTF substrate>

Polymer: Toray (TORAY) Co., Ltd., polyethylene terephthalate (PET) 188μm

Silver paste: about 10μm

* Apply resist to silver paste

Spacing: 3mm

<90 degree peel strength>

As shown in Fig. 4, the sample for FPC/PTF test was peeled off at a tensile speed of 100 mm/min and a peeling direction of 90 degrees by a tensile tester (PT-200N manufactured by MINEBEA Co., Ltd.). And determine the maximum value at the time of the fracture.

<connection resistance>

As shown in Fig. 5, a low resistance meter (HIOKI system, DC mode 3227 milliohm tester (MILLIOHM HiTester)) was used between the FPC terminal terminals of the FPC/PTF test samples to measure ab, bc, and Connect the resistance between cd and find the average.

<heat aging resistance>

After maintaining at 80 ° C for 1,000 hours, the 90-degree peel strength was measured by the above method, and evaluated by the following criteria: A: 5 N/cm or more; B: less than 5 N/cm.

<Printing workability>

The printing of the adhesive composition was carried out using a screen 80 mesh (TETORON (registered trademark)), and the dried film thickness (drying temperature 120 ° C, 15 minutes) was maintained at 20 ± 5 μm. By visual observation, the presence or absence of problems such as sticking, detachment, foaming, and penetration between the screen and the printed matter was observed and evaluated by the following criteria:

A: No problems such as sticking, stripping, foaming, and penetration, and the printing workability is good;

B: There are a number of problems, but the printability is slightly good for the allowable range;

C: There is obviously a problem, and the printing workability is not good.

<Touch dry>

The adhesive composition was applied to a smooth surface at a thickness of 20 ± 5 μm, and dried at a temperature of 100 ° C for 15 minutes, and then the coating film was touched with a fingertip to investigate the presence or absence of adhesion (viscosity), and was evaluated on the following basis:

A: no stickiness, good;

B: There are a few stickiness, slightly better;

C: Obviously sticky, not good.

<Pressure workability>

Using a thermostatic heater type press machine (HBM-10, manufactured by Bridge Manufacturing Co., Ltd.), pressure-bonding was performed at a pressure of 130 ° C to 140 ° C, a pressure of 3 MPa, and a time of 15 seconds, and visual observation was carried out. The presence or absence of problems such as resin flow and voids is evaluated by the following criteria:

A: No problem, good pressurization workability;

B: There are a number of problems, but for the allowable range, the pressurization workability is slightly good;

C: Obviously problematic, the pressurization workability is not good.

<Coating workability>

The adhesive composition was applied to a smooth surface at a thickness of 20 ± 5 μm, and dried at a temperature of 120 ° C for 5 minutes, and then visually judged whether or not the coating film was adhered (adhesive), and the presence or absence of voids in the coating film. And evaluated by the following benchmarks:

A: no adhesion and no gap, good;

B: There are some gaps, but no adhesion, slightly better;

C: There are adhesions and voids, which is not good.

<Thickness uniformity>

With respect to Example 9, Example 10, Example 13, Example 14, and Comparative Example 3, the adhesive composition was applied onto a smooth surface and dried to form a film having a thickness of 35 μm and a width of 300 mm in width. In the three directions (left, center, and right), the film thickness was measured 10 times (n=30) every 10 cm in the longitudinal direction, and evaluated based on the following criteria. In the film thickness measurement system, the film is embedded in the resin and hardened, whereby the cross section in the thickness direction of the film is exposed, and the cross section is observed by a CCD camera, and the thickness is measured.

A: less than the standard deviation of 3 μm;

B: standard deviation of 3 μm or more and less than 5 μm;

C: standard deviation of 5 μm or more and less than 7 μm;

D: The standard deviation is 7 μm or more.

Industrial availability

The adhesive composition of the present invention can be suitably used as a paste or a film for connection to various substrates, that is, a connection between a liquid crystal panel and a substrate, or a connection of a film switch, and connection of an EL backlight terminal.

1. . . Flexible printed circuit board (FPC)

2. . . Polymer thick film (PTF) substrate

3. . . Substance composition (paste or film)

Fig. 1 is a plan view showing a flexible printed circuit board (hereinafter, abbreviated as FPC) 1 used in an embodiment of the present invention.

Fig. 2 is a plan view showing a thick film of a polymer (hereinafter sometimes abbreviated as PTF) used in the embodiment of the present invention.

Fig. 3 is a plan view showing the connection position of the aforementioned FPC1 and the PTF substrate 2.

Fig. 4 is a perspective view and a cross-sectional view showing a test method of 90-degree peel strength.

Fig. 5 is a plan view showing a method of measuring the connection resistance.

Claims (9)

A conductive adhesive composition comprising a resin component, a solvent, and an electroconductive particle, wherein the resin component is a polyether ester decylamine, and a styrene-isobutylene-styrene-based olefin elastomer, styrene- One or more selected from the group consisting of an ethylene-butylene-styrene-based olefin elastomer and an olefin elastomer selected from the maleic anhydride-modified materials, and the polyether ester decylamine and the olefin elastomer The blending ratio is from 1 part by weight to 300 parts by weight based on 100 parts by weight of the polyether ester decylamine. The conductive adhesive composition of claim 1, which further comprises 10 parts by weight to 100 parts by weight of the urethane elastomer based on 100 parts by weight of the polyether ester guanamine. The conductive adhesive composition according to the first aspect of the invention, which further comprises 1 part by weight to 100 parts by weight of the polyester resin based on 100 parts by weight of the polyether ester decylamine. The conductive adhesive composition of the first aspect of the invention is further contained in an amount of from 1 part by weight to 100 parts by weight based on 100 parts by weight of the polyether phthalamide. The conductive adhesive composition of claim 1, which further comprises 5 parts by weight to 50 parts by weight of the epoxy resin based on 100 parts by weight of the polyether ester guanamine. The conductive adhesive composition according to any one of claims 1 to 5, wherein the content of the conductive particles is relative to the conductive adhesive group The total resin solid content in the product is in the range of 1 part by weight to 100 parts by weight based on 100 parts by weight of the total. The conductive adhesive composition according to any one of claims 1 to 5, wherein the solvent is used in an amount such that the resin solid content of the conductive adhesive composition is in the range of 10% by weight to 50% by weight. . The conductive adhesive composition of claim 6, wherein the solvent is used in an amount such that the resin solid content of the conductive adhesive composition is in the range of 10% by weight to 50% by weight. A conductive adhesive film comprising the adhesive composition according to any one of claims 1 to 8.