KR102469837B1 - Connection structure, and anisotropic conductive adhesive - Google Patents

Abstract

(assignment)
Provided is a connection structure and an anisotropic conductive adhesive capable of preventing the appearance of a decorative printing unit from being damaged even when a defect such as a pinhole occurs in the decorative printing unit.
(solution)
A connection structure comprising: a first electronic component (10) in which an electrode (13) is formed on a decorative layer (12), and a second electronic component (10) in which an electrode (22) facing the electrode (13) of the first electronic component (10) is formed. An anisotropic conductive film 30 connecting the electronic component 20 and the electrode 13 of the first electronic component 10 and the electrode 22 of the second electronic component 20 are provided, and the anisotropic conductive film 30 ) is made of a cured product of an anisotropic conductive adhesive containing conductive particles 31 and black pigment 32. Thereby, the light leakage of the pinhole of the decorative printing part can be reduced, and the design of the decorative printing part can be maintained.

Description

Connection structure and anisotropic conductive adhesive {CONNECTION STRUCTURE, AND ANISOTROPIC CONDUCTIVE ADHESIVE}

The present invention relates to a connection structure in which electronic components are connected using an anisotropic conductive adhesive and an anisotropic conductive adhesive.

In recent years, in order to improve design freedom, for example, in a cover glass integrated touch panel, it has been proposed to form electrodes on a decorative layer decorated and printed in a frame shape on the outer periphery, and bonded to a circuit member on the decorative layer. .

However, when a defect such as a pinhole occurs in the decorative printed portion, light leakage or the like occurs due to irradiation light from the backlight, and the appearance is damaged. In addition, even if a pinhole is found in the decorative printing portion by inspection, it is difficult to repair it because wiring has already been formed on the decorative layer.

Japanese Unexamined Patent Publication No. 2009-088465

The present invention has been proposed in view of such a conventional situation, and provides a connection structure and an anisotropic conductive adhesive capable of preventing the appearance of the decorative printing unit from being damaged even when a defect such as a pinhole occurs in the decorative printing unit aims to

In order to solve the above problems, a connection structure according to the present invention comprises: a first electronic component having an electrode formed on a decorative layer; a second electronic component having an electrode facing the electrode of the first electronic component; An anisotropic conductive film connecting an electrode of one electronic component and an electrode of the second electronic component is provided, and the anisotropic conductive film is made of a cured product of an anisotropic conductive adhesive containing conductive particles and a black pigment.

Further, a touch panel according to the present invention includes a display window having a touch panel function, a decorative layer formed on a periphery other than the display window, a first electronic component on which electrodes are formed on the decorative layer, and the first electronic component. and an anisotropic conductive film connecting the electrode of the first electronic component and the electrode of the second electronic component, wherein the anisotropic conductive film comprises conductive particles and a black pigment. It is characterized in that it consists of a cured product of an anisotropic conductive adhesive containing

Further, the anisotropic conductive adhesive according to the present invention is characterized by containing a film forming resin, a radical polymerizable resin, a radical polymerization initiator, conductive particles, and a black pigment in which carbon is not the main ingredient.

Further, in the method for manufacturing a bonded structure according to the present invention, an anisotropic conductive film containing conductive particles and a black pigment is temporarily applied onto an electrode of a first electronic component in which an electrode is formed on a decorative layer, and on the anisotropic conductive film A second electronic component is placed on the second electronic component, and pressurized with a compression head from the upper surface of the second electronic component.

According to the present invention, since the black pigment of the anisotropic conductive film reduces light leakage in the decorative printing section, it is possible to prevent the appearance of the decorative printing section from being damaged.

1 is a cross-sectional view showing a connection structure to which the present invention is applied.
2 is a perspective view showing an example of a connection structure.
Fig. 3 is a photograph of a bonded structure manufactured using an anisotropic conductive film of Example 3, observed with a metallographic microscope from the side of the FPC for evaluation with illumination being applied from the side of the glass substrate for evaluation.
Fig. 4 is a photograph of a bonded structure manufactured using an anisotropic conductive film of Comparative Example 1, observed with a metallographic microscope from the side of the FPC for evaluation with illumination being applied from the side of the glass substrate for evaluation.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail in the following order, referring drawings.

1. Connection structure

2. Anisotropic conductive adhesive

3. Examples

<1. connection structure>

1 is a cross-sectional view showing a bonded structure to which the present invention is applied. As shown in FIG. 1, the bonded structure includes a first electronic component 10 in which an electrode 13 is formed on a decorative layer 12, and an electrode facing the electrode 13 of the first electronic component 10 ( 22) is formed on the second electronic component 20, and an anisotropic conductive film 30 connecting the electrode 13 of the first electronic component 10 and the electrode 22 of the second electronic component 20 is provided. . Further, the anisotropic conductive film 30 is made of a cured product of an anisotropic conductive adhesive containing conductive particles 31 and a black pigment 32 . Thus, even when a defect such as a pinhole occurs in the decorative printing portion, the black pigment 32 of the anisotropic conductive film 30 reduces light leakage in the decorative printing portion, thereby preventing the appearance of the decorative printing portion from being damaged. can

The first electronic component 10 includes a transparent substrate 11, a decorative layer 12 decorated and printed on the transparent substrate, and an electrode 13 formed on the decorative layer 12.

As the transparent substrate 11, for example, one having a transmittance of 80% or more with respect to visible light can be used, and one having a transmittance of 95% or more preferably can be used. Inorganic transparent substrates, such as glass generally used in liquid crystal display devices, or transparent resin substrates, such as polycarbonate, polymethyl methacrylate, polyethylene terephthalate, and cyclic olefin copolymer, can be used.

The decorative layer 12 is formed by the hardened|cured material of a colored resin composition. The colored resin composition is prepared by dispersing a coloring agent in a resin binder containing, for example, a monomer, a photopolymerization initiator, a sensitizer, a solvent and the like. The coloring agent colors the decorative layer 12 in a desired color, and a pigment or dye can be used. As a pigment, either an organic pigment or an inorganic pigment may be sufficient, and the compounding quantity is not specifically limited. As the color of the decorative layer 12, black with light-shielding properties is preferably used from the viewpoints of design and productivity. When design is important, a metal layer may be formed, but even in this case, in many cases, a resin layer is formed on the outermost surface of a coating material or the like, and the material of the adhesive surface does not differ greatly.

As such a 1st electronic component 10, a cover glass integrated touch panel is mentioned, for example. The cover glass-integrated touch panel includes a display window having a touch panel function in which a signal line for detecting a touch position is formed, formed on a surface opposite to the viewing side of the transparent substrate 11, and formed on a periphery other than the display window. It has a decorative layer (12). In the display window portion, for example, as a capacitive touch panel layer, transparent electrodes such as indium tin oxide (ITO), indium zinc oxide (IZO), and silicon nitride (SiNx) are formed. Even if the cover glass is replaced with a glass substitute material, there is no problem in particular because it does not relate to the essence of the invention.

The second electronic component 20 includes a substrate 21 and an electrode 22 formed on the substrate 21 . As such a 2nd electronic component, FPC (Flexible Printed Circuits), IC (Integrated Circuit), etc. are mentioned.

The anisotropic conductive film 30 is made of a cured product of an anisotropic conductive adhesive containing conductive particles 31 and a black pigment 32, and the first electronic component 10 and the second electronic component 10 are formed by the conductive particles 31. The electronic component 20 is electrically connected.

As the anisotropic conductive adhesive, any of a radical polymerization type, anionic polymerization type, cationic polymerization type, etc. may be used, but a radical polymerization type that can be cured at a lower temperature and causes less thermal damage to the decorative layer 12 is preferable. .

A radical polymerization type anisotropic conductive adhesive contains a film forming resin, a radical polymerization resin, a radical polymerization initiator, conductive particles, and a black pigment. Here, since carbon black generally used as a black pigment has radical complementarity and becomes a factor of curing inhibition, a black pigment in which carbon is not the main ingredient is used for the radical polymerization type anisotropic conductive adhesive. Black pigments in which carbon is not the main raw material include titanium-based black pigments.

In the connection structure having such a configuration, an anisotropic conductive film is temporarily attached to an electrode 13 of a first electronic component 10, the second electronic component 20 is disposed on the anisotropic conductive film, and a second electronic component 20 is formed. It is produced by pressing with a crimping head from the upper surface of the electronic component 20. According to such a manufacturing method, while electrically connecting the electrode 13 of the 1st electronic component 10 and the electrode 22 of the 2nd electronic component 20 via the electroconductive particle 31, anisotropic conduction The first electronic component 10 and the second electronic component 20 can be bonded by the anisotropic conductive film 30 obtained by curing the film.

<2. Anisotropic conductive adhesive>

Next, the anisotropic conductive adhesive used for the above-described connection structure will be described. The anisotropic conductive adhesive in the present embodiment contains a film-forming resin, a radical polymerizable resin, a radical polymerization initiator, conductive particles, and a black pigment in which carbon is not the main ingredient.

The film-forming resin corresponds to a high molecular weight resin having an average molecular weight of 10000 or more, and preferably has an average molecular weight of about 10000 to 80000 from the viewpoint of film formation. Examples of the film-forming resin include various resins such as phenoxy resins, polyester urethane resins, polyester resins, polyurethane resins, acrylic resins, polyimide resins, and butyral resins, and these may be used alone. You may use a combination of more than one type. Among these, a phenoxy resin is preferably used from the viewpoints of film formation state, connection reliability and the like. The content of the film-forming resin is usually 30 to 80 parts by mass, preferably 40 to 70 parts by mass, based on 100 parts by mass of the adhesive composition.

The radically polymerizable resin is a substance having a functional group polymerized by a radical, and examples thereof include epoxy acrylate, urethane acrylate, and polyester acrylate, and these may be used alone or in combination of two or more. can also Among these, epoxy acrylate is preferably used in this embodiment. The content of the radically polymerizable resin is usually 10 to 60 parts by mass, preferably 20 to 50 parts by mass, based on 100 parts by mass of the adhesive composition.

A known radical polymerization initiator can be used, and organic peroxides can be preferably used among them. Examples of organic peroxides include peroxyketals, diacyl peroxides, peroxydicarbonates, peroxyesters, dialkyl peroxides, hydroperoxides, and silyl peroxides. , and may be used in combination of two or more types. Among these, peroxyketals are preferably used in the present embodiment. The content of the radical polymerization initiator is usually 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, based on 100 parts by mass of the radical adhesive composition.

Further, as the conductive particles, for example, metal particles such as gold particles, silver particles, nickel particles, and resin particles such as benzoguanamine resin and styrene resin are coated with a metal such as gold, nickel, or zinc. Resin particles and the like can be used. The average particle diameter of these conductive particles is 1 to 30 µm, more preferably 3 to 20 µm.

The black pigment is not particularly limited as long as carbon is not the main raw material, and titanium-based black pigments such as titanium oxide, oxides of iron (magnetite-type triiron tetroxide), composite oxides of copper and chromium, composites of copper, chromium, and zinc Oxide type black pigments, such as an oxide, etc. can be used.

When using a titanium-based black pigment, it is preferable that the average primary particle size is 60 nm or more and 800 nm or less. In addition, it is preferable to blend 2 to 40 parts by mass of the titanium-based black pigment with respect to 100 parts by mass of the adhesive component. Thus, a bonded structure excellent in conduction resistance, peeling strength and light-shielding properties can be obtained.

Moreover, it is preferable to add a silane coupling agent as another additive composition to the binder. As a silane coupling agent, an epoxy type, an amino type, a mercapto type, a sulfide type, a ureido type, etc. are mentioned.

Further, in order to improve the adhesion to the inorganic substrate, it is preferable to add phosphoric acid acrylate. Examples of phosphoric acid acrylate include curable phosphoric acid ester compounds that are reaction products of 2-hydroxyethyl methacrylate and phosphoric acid.

Moreover, you may add an inorganic filler. As an inorganic filler, silica, talc, calcium carbonate, magnesium oxide, etc. can be used, and the kind of inorganic filler is not specifically limited. Further, when blending the respective components of these binders, toluene, ethyl acetate or a mixed solvent thereof is preferably used.

Since the anisotropic conductive adhesive having such a configuration is formulated with black pigment instead of carbon as the main raw material, it can reduce the light leakage from the pinhole of the decorative printed portion without inhibiting the radical reaction, thereby preventing the appearance of the decorative printed portion from being damaged. can

<3. Example>

Hereinafter, embodiments of the present invention will be described. In this example, a radical curable anisotropic conductive film containing a black pigment was prepared, and transmittance of the anisotropic conductive film was measured. Further, a bonded structure was prepared using the anisotropic conductive film, and conduction resistance, peeling strength, and light-shielding properties of the bonded structure were evaluated. In addition, this invention is not limited to these Examples.

Measurement of the transmittance of the anisotropic conductive film, preparation of the connected structure, measurement of conduction resistance, measurement of peel strength, and evaluation of light-shielding properties were performed as follows.

[Measurement of Transmittance of Anisotropic Conductive Film]

The transmittance of the anisotropic conductive adhesive film in an uncured state was measured using a spectrophotometer (UV-3600 manufactured by Shimadzu Corporation).

[Manufacture of connection structure]

Fig. 2 is a perspective model diagram showing a connection structure in the present embodiment. Glass for evaluation that becomes glass/black ink layer/ITO by coating the surface of glass having a thickness of 0.7 mm with black ink (GLS-HF919 manufactured by Teikoku Ink Co., Ltd.) to a thickness of 5 μm, and coating the surface with ITO (Indium Tin Oxide) A substrate 51 was produced. Further, in the black ink layer, 150 to 200 pinholes were formed per mm 2 with a size of 1 μm to 6 μm. The glass substrate 51 for evaluation is the same as the well-known ITO (Indium Tin Oxide) coated glass substrate for evaluation (the whole surface ITO coating, glass thickness of 0.7 mm) except having a black ink layer as an intermediate|middle layer. The glass substrate 51 for evaluation and the FPC (400 μmP, Cu 18 μmt-Au plating, 25 μmt-Espanex-S substrate) 52 for evaluation are bonded using an anisotropic conductive film 53 made it

An anisotropic conductive film 53 slit to a width of 1.5 mm was attached to a glass substrate 51 for evaluation, and the FPC 52 was temporarily fixed thereon, and then a buffer material (polytetrafluoroethylene) with a thickness of 100 μm was applied. Using a heat tool with a width of 1.5 mm, bonding was performed under conditions of 150°C - 4 MPa - 10 sec to prepare a bonded structure.

[Measurement of conduction resistance]

About the bonded structure, connection resistance was measured about the initial stage and after the high-temperature, high-humidity test of 60 degreeC/95%/500 hr. Connection resistance when a current of 1 mA was passed was measured by the 4-terminal method using a digital multimeter (product number: digital multimeter 7555, manufactured by Yokogawa Electric Co., Ltd.).

[Measurement of Peel Strength]

Peel strength was measured for the bonded structure at an initial stage and after a high-temperature, high-humidity test at 60°C/95%/500 hr. The 90° peeling test (JIS K 6854-1) in which the FPC 52 for evaluation is peeled from the glass substrate 51 for evaluation in the 90° direction was conducted, and the peel strength (N/cm) was measured.

[Evaluation of light-shielding properties]

Regarding the bonded structure, irradiated with illumination from the side of the glass substrate 51 for evaluation on which pinholes were formed in advance, observed with a metallographic microscope from the side of the FPC 52 for evaluation, and the case where the number of pinholes per 1 mm was less than 10 was "◎", The case where the number of pinholes per 1 mm 2 was 10 or more and less than 50 was evaluated as “○”, and the case where the number of pinholes per 1 mm 2 was 50 or more was evaluated as “x”.

[Total Judgment]

A case where the evaluation of the light shielding property was "◎" and the conduction resistance after the high temperature, high humidity test was less than 5.0 Ω was evaluated as "A". In addition, the case where evaluation of light-shielding property was "◎", and the case where the conduction resistance after a high-temperature, high-humidity test was 5.0 Ω or more and less than 10.0 Ω was evaluated as "B". A case where the light-shielding property was evaluated as "◎", and a case where the conduction resistance after the high-temperature, high-humidity test was 10.0 Ω or more was evaluated as "C". In addition, the case where evaluation of the light-shielding property was "○" and the conduction resistance after the high-temperature, high-humidity test was less than 5.0 Ω was evaluated as "B". In addition, the case where evaluation of the light-shielding property was "○" and the conduction resistance after the high-temperature, high-humidity test was 5.0 Ω or more was evaluated as "C". In addition, the case where evaluation of light-shielding property was "x" was evaluated as "C".

[Example 1]

As film forming resin, polyester urethane resin (product name: UR8200, manufactured by Toyobo Co., Ltd., dissolved at 20% by mass in a mixed solvent of methyl ethyl ketone/toluene = 50/50) 60 parts by mass, radically polymerizable resin (product name: EB-600, manufactured by Daicel Cytech Co., Ltd.) 34 parts by mass, silane coupling agent (product name: KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) 1 part by mass, phosphoric acid acrylate (product name: P-1M, manufactured by Kyoei Chemical Co., Ltd.) 1 Conductive particles (product name: AUL705, manufactured by Sekisui Chemical Industry Co., Ltd.) were dispersed to a particle density of 5000/mm2 in an adhesive containing 4 parts by mass of parts by mass and a reaction initiator (product name: Perhexa C, manufactured by Nippon Oil Co., Ltd.). An anisotropic conductive film having a thickness of 20 μm was prepared by dispersing 12 parts by mass of a titanium-based black pigment (product name: 12S, manufactured by Mitsubishi Material Co., Ltd.) having an average primary particle size of 60 nm.

The transmittance of the anisotropic conductive film of Example 1 was 13.4%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 2.2 Ω, and the conduction resistance after the high-temperature, high-humidity test was 7.0 Ω. Moreover, the initial peeling strength was 6.0 N/cm, and the peeling strength after a high-temperature, high-humidity test was 4.1 N/cm. Moreover, evaluation of the light-shielding property was (double-circle). Therefore, the total judgment was B. Table 1 shows these results.

[Example 2]

An anisotropic conductive film was produced in the same manner as in Example 1, except that 12 parts by mass of titanium-based black pigment (product name: 13M-C, manufactured by Mitsubishi Material) having an average primary particle size of 100 nm was dispersed.

The transmittance of the anisotropic conductive film of Example 2 was 13.3%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 2.0 Ω, and the conduction resistance after the high-temperature, high-humidity test was 5.5 Ω. Moreover, the initial peeling strength was 6.1 N/cm, and the peeling strength after a high-temperature, high-humidity test was 4.0 N/cm. In addition, evaluation of the light-shielding property was (double-circle). Therefore, the total judgment was B. Table 1 shows these results.

[Example 3]

An anisotropic conductive film was manufactured in the same manner as in Example 1, except that 12 parts by mass of a titanium-based black pigment (trade name: Tilack D, manufactured by Ako Kasei) having an average primary particle size of 800 nm was dispersed.

The transmittance of the anisotropic conductive film of Example 3 was 13.8%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 1.8 Ω, and the conduction resistance after the high-temperature, high-humidity test was 3.2 Ω. Moreover, the initial peeling strength was 6.0 N/cm, and the peeling strength after a high-temperature, high-humidity test was 4.3 N/cm.

3 is a photograph of the bonded structure manufactured using the anisotropic conductive film of Example 3, observed with a metallographic microscope from the side of the FPC for evaluation with illumination from the side of the glass substrate for evaluation in which pinholes were formed in advance. A pinhole was not observed, and the evaluation of the light-shielding property was ◎. Therefore, the total judgment was A. Table 1 shows these results.

[Comparative Example 1]

An anisotropic conductive film was prepared in the same manner as in Example 1, except that the black pigment was not dispersed.

The transmittance of the anisotropic conductive film of Comparative Example 1 was 84.6%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 1.8 Ω, and the conduction resistance after the high-temperature, high-humidity test was 3.0 Ω. Moreover, the initial peeling strength was 5.8 N/cm, and the peeling strength after a high-temperature, high-humidity test was 4.0 N/cm.

4 is a photograph of the bonded structure manufactured using the anisotropic conductive film of Comparative Example 1, observed with a metallographic microscope from the side of the FPC for evaluation with illumination from the side of the glass substrate for evaluation on which pinholes were formed in advance. A pinhole was observed, and the evaluation of the light-shielding property was x. Therefore, the total judgment was C. Table 1 shows these results.

[Comparative Example 2]

An anisotropic conductive film was manufactured in the same manner as in Example 1, except that 1 part by mass of a titanium-based black pigment (product name: Tilack D, manufactured by Ako Kasei Co., Ltd.) having an average primary particle diameter of 800 nm was dispersed.

The transmittance of the anisotropic conductive film of Comparative Example 2 was 67.4%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 1.8 Ω, and the conduction resistance after the high-temperature, high-humidity test was 3.2 Ω. Moreover, the initial peel strength was 5.9 N/cm, and the peel strength after a high-temperature, high-humidity test was 4.0 N/cm. Moreover, evaluation of the light-shielding property was x. Therefore, the total judgment was C. Table 1 shows these results.

[Example 4]

An anisotropic conductive film was manufactured in the same manner as in Example 1, except that 2 parts by mass of a titanium-based black pigment (product name: Tilack D, manufactured by Ako Kasei Co., Ltd.) having an average primary particle size of 800 nm was dispersed.

The transmittance of the anisotropic conductive film of Example 4 was 50.3%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 1.8 Ω, and the conduction resistance after the high-temperature, high-humidity test was 3.0 Ω. Moreover, the initial peeling strength was 6.0 N/cm, and the peeling strength after a high-temperature, high-humidity test was 4.2 N/cm. Moreover, evaluation of the light-shielding characteristic was (circle). Therefore, the total judgment was B. Table 1 shows these results.

[Example 5]

An anisotropic conductive film was produced in the same manner as in Example 1, except that 5 parts by mass of a titanium-based black pigment (product name: Tilack D, manufactured by Ako Kasei) having an average primary particle diameter of 800 nm was dispersed.

The transmittance of the anisotropic conductive film of Example 5 was 17.9%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 1.8 Ω, and the conduction resistance after the high-temperature, high-humidity test was 3.1 Ω. Moreover, the initial peeling strength was 6.1 N/cm, and the peeling strength after a high-temperature, high-humidity test was 4.0 N/cm. Moreover, evaluation of the light-shielding property was (double-circle). Therefore, the total judgment was A. Table 1 shows these results.

[Example 6]

An anisotropic conductive film was manufactured in the same manner as in Example 1 except that 36 parts by mass of a titanium-based black pigment (product name: Tilack D, manufactured by Ako Kasei) having an average primary particle size of 800 nm was dispersed.

The transmittance of the anisotropic conductive film of Example 6 was 11.2%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 2.3 Ω, and the conduction resistance after the high-temperature, high-humidity test was 7.9 Ω. Moreover, the initial peeling strength was 6.3 N/cm, and the peeling strength after a high temperature, high humidity test was 4.1 N/cm. Moreover, evaluation of the light-shielding property was (double-circle). Therefore, the total judgment was B. Table 1 shows these results.

[Comparative Example 3]

An anisotropic conductive film was manufactured in the same manner as in Example 1 except that 48 parts by mass of a titanium-based black pigment (product name: Tilack D, manufactured by Ako Kasei) having an average primary particle size of 800 nm was dispersed.

The transmittance of the anisotropic conductive film of Comparative Example 3 was 10.7%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 2.5 Ω, and the conduction resistance after the high-temperature, high-humidity test was 11.3 Ω. Moreover, the initial peeling strength was 6.5 N/cm, and the peeling strength after a high-temperature, high-humidity test was 4.2 N/cm. Moreover, evaluation of the light-shielding property was (double-circle). Therefore, the total judgment was C. Table 1 shows these results.

[Comparative Example 4]

An anisotropic conductive film was produced in the same manner as in Example 1, except that 12 parts by mass of carbon black (product name: #2350, manufactured by Mitsubishi Chemical) having an average primary particle size of 15 nm was dispersed as a black pigment.

The transmittance of the anisotropic conductive film of Comparative Example 4 was 12.0%. Further, the initial conduction resistance of the bonded structure manufactured using the anisotropic conductive film was 5.2 Ω, and the conduction resistance after the high-temperature, high-humidity test was 10.6 Ω. Moreover, the initial peeling strength was 1.5 N/cm, and the peeling strength after a high-temperature, high-humidity test was 0.5 N/cm. Moreover, evaluation of the light-shielding property was (double-circle). Therefore, the total judgment was C. Table 1 shows these results.

As shown in Table 1, it was found that by blending an appropriate amount of black pigment, a repair function for preventing light leakage from a pinhole could be imparted, and the design of the decorative portion could be maintained. As shown in Examples 1 to 6, in the case of using a titanium-based black pigment, by blending 2 to 40 parts by mass of an average primary particle size of 60 nm or more and 800 nm or less with respect to 100 parts by mass of the adhesive component, conduction resistance, It was found that a bonded structure excellent in peeling strength and light-shielding properties was obtained. In addition, as shown in Comparative Example 4, since carbon black has radical replenishment properties and becomes a factor of curing inhibition, in the case of a radical curable anisotropic conductive film, it is necessary to use a black pigment other than carbon black.

10: first electronic component
11: transparent substrate
12: decorative layer
13: electrode
20: second electronic component
21: Substrate
22; electrode
30: anisotropic conductive film
51: glass substrate
52: FPC
53: anisotropic conductive film

Claims (13)

delete delete delete delete delete delete delete delete A second electronic component is disposed on an electrode of a first electronic component having an electrode formed on the decorative layer through an anisotropic conductive film containing conductive particles and a black pigment that does not contain carbon;
Pressing with a crimping head from the upper surface of the second electronic component,
The anisotropic conductive film contains a film forming resin, a radical polymerizable resin, a radical polymerization initiator, conductive particles, and a black pigment that does not contain carbon, and when the thickness is 20 μm, 11.2% or more with respect to visible light has a transmittance of 17.9% or less;
When the anisotropic conductive film is used and the first electronic component and the second electronic component in which electrodes are formed are connected on a decorative layer in which pinholes having a diameter of 1 μm to 6 μm are formed, the number of pinholes through which illumination light is transmitted is 1 The manufacturing method of the bonded structure which is less than 50 per mm<2>. a first electronic component having electrodes formed on the decorative layer;
a second electronic component having an electrode facing the electrode of the first electronic component;
an anisotropic conductive film connecting an electrode of the first electronic component and an electrode of the second electronic component;
The anisotropic conductive film contains a film-forming resin, a radical polymerizable resin, a radical polymerization initiator, conductive particles, and a carbon-free black pigment, and when the thickness is 20 μm, 11.2% or more with respect to visible light 17.9 An anisotropic conductive film having a transmittance of 1% or less, wherein the anisotropic conductive film is used to connect a first electronic component and a second electronic component in which electrodes are formed on a decorative layer in which pinholes having a diameter of 1 μm to 6 μm are formed. In one case, a connection structure made of a cured product of an anisotropic conductive film in which the number of pinholes through which illumination light is transmitted is less than 50 per 1 mm 2 . According to claim 10,
The anisotropic conductive film is a cured product of a radical polymerization type anisotropic conductive adhesive,
A connected structure in which the black pigment does not contain carbon. According to claim 10,
A bonded structure in which the black pigment is a titanium-based black pigment. A display window having a touch panel function, a decorative layer formed on a periphery other than the display window, and a first electronic component on which electrodes are formed on the decorative layer;
a second electronic component having an electrode facing the electrode of the first electronic component;
An anisotropic conductive film connecting an electrode of the first electronic component and an electrode of the second electronic component, wherein the anisotropic conductive film comprises a film forming resin, a radical polymerizable resin, a radical polymerization initiator, conductive particles, and carbon. An anisotropic conductive film that contains a black pigment that does not contain and has a visible light transmittance of 11.2% or more and 17.9% or less when the thickness is 20 μm, wherein the anisotropic conductive film is used and has a diameter of 1 μm to 6 μm A touch panel made of a cured product of an anisotropic conductive film in which the number of pinholes through which illumination light is transmitted is less than 50 per 1 mm 2 when a first electronic component in which an electrode is formed on a decorative layer having a phosphorus pinhole and a second electronic component are connected. .

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