JP2018116959A - Circuit board device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit board device which is excellent in connection reliability and hardly causes troubles even when stress due to bending and pulling is applied.SOLUTION: A circuit board device according to an embodiment of the present invention includes a deformable circuit board, an electronic member provided on at least one main surface of the circuit board, and a cured product of a liquid resin composition (a) for sealing at least a part of the electronic member, and the stretch recovery ratio of the cured product of the resin composition (a) is 80% or more.SELECTED DRAWING: None

Description

  The present invention relates to a circuit board device.

  In recent years, in addition to being small in size, electronic devices have been required to be usable on curved surfaces such as the body so that they can be easily worn on the body, and to be difficult to cause poor connection even when attached and detached. There is an increasing demand for wearable devices having flexibility and elasticity.

  A flexible printed circuit (FPC) has flexibility but does not have elasticity. Therefore, a circuit board is known in which a rigid substrate is laminated on a corrugated FPC etched (Patent Document 1). In this circuit board, the FPC can be deformed by twisting, but the FPC itself does not expand and contract.

  In addition, in order to provide a circuit board having elasticity, a stretchable cable composed of a wiring having elasticity on a sheet-like base material having elasticity has been proposed (Patent Document 2,). 3).

Special table 2009-533839 JP 2016-178121 A Japanese Patent No. 6002322

  The flexible printed circuit board can be deformed by twisting and bending, and the stretchable cable itself can be deformed. On the other hand, electronic components including semiconductor elements such as IC (Integrated Circuit) chips, memories, capacitors, inductors, etc. remain as conventional undeformed components. When this component is mounted on a deformable circuit board (for example, a stretchable cable), a connection failure occurs due to stress (deformation stress) caused by twisting, bending, stretching, etc. A bug may occur. In addition, when wiring that cannot be deformed is provided on the circuit board, problems such as disconnection may occur due to stress (deformation stress) caused by twisting, bending, stretching (pulling), or the like.

  Further, circuit board devices such as semiconductor devices are required to improve connection reliability in addition to the suppression of the occurrence of the above problems.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a circuit board device that is excellent in connection reliability and that is less likely to fail even when stress due to bending and pulling is applied.

  A circuit board device according to one aspect of the present invention includes a deformable circuit board, an electronic member (for example, an electronic component, a wiring, and the like) provided on at least one main surface of the circuit board, and at least one of the electronic members. And a liquid resin composition (a) for sealing the part, and the stretch recovery rate of the cured product of the resin composition (a) is 80% or more.

  In the said circuit board apparatus, since the expansion-contraction recovery rate of the hardened | cured material of a resin composition (a) is 80% or more, the stress by bending and a tension | pulling is relieved. Therefore, according to the circuit board device, even when stress due to bending or pulling is applied, defects (for example, peeling and cracking of electronic components, cutting of wiring, etc.) are unlikely to occur.

  In one embodiment, the tensile elastic modulus at 25 ° C. of the circuit board may be 3 MPa or more. In this case, since the mechanical properties (particularly toughness and wear resistance) are excellent, it is possible to make the circuit board thinner even in applications where strength is required.

  In one aspect, the tensile modulus at 25 ° C. of the circuit board may be less than 3 MPa. In this case, there is little stress when deforming (especially when expanding and contracting).

  In one embodiment, the resin composition (a) may be photocurable. In this case, the resin composition (a) can be cured at room temperature.

  In one aspect, the circuit board may have a deformable wiring on at least one main surface. In this case, the wiring is deformed by pulling or the like, but since the cured product of the resin composition (a) has stretchability, it can follow the deformation of the wiring, relieve the stress on the wiring, and suppress the disconnection of the wiring.

  In one embodiment, the resin composition (a) comprises (A) a styrenic elastomer, (B) a monofunctional (meth) acrylate having an alkyl chain, and (C) a monofunctional (meta) having an alicyclic skeleton. ) An acrylate, (D) a bifunctional or higher functional compound having two or more ethylenically unsaturated groups, and (E) a polymerization initiator. Since this resin composition (a) is excellent in stretchability and adhesion, in this embodiment, the occurrence of problems due to the stress (for example, peeling and cracking of electronic components, cutting of wiring, etc.) tends to be further suppressed. is there. Moreover, there exists a tendency for the connection reliability of a circuit board apparatus to improve further by using the said resin composition (a). The reason why the connection reliability is further improved by this embodiment is not clear, but it is considered that one of the causes is that the styrene-based elastomer as the component (A) contributes to the improvement of the connection reliability. That is, the elastomer (polymer) component in the resin composition greatly affects the physical properties at high temperatures (100 ° C. or higher). Since the styrene elastomer has a styrene skeleton, the elastic modulus decreases at high temperatures (100 ° C. or higher). Can be suppressed. Further, since the styrene elastomer is hydrophobic, the moisture permeability and water supply rate at a high temperature can be lowered. As described above, the styrene elastomer contributes to the improvement of reliability under high temperature and high humidity. In this aspect, the component (A), which is an elastomer component, contributes to the improvement of reliability at high temperatures, so that it is considered that the connection reliability of the circuit board device is further improved.

  In one embodiment, the component (A) may be a hydrogenated elastomer. In this case, the weather resistance tends to be excellent.

  In one embodiment, the component (E) may be a radical photopolymerization initiator. In this case, in addition to being able to cure at room temperature, the workability is excellent because the curing speed is high.

  In one embodiment, the carbon number of the alkyl chain in the component (B) may be 12 or less. In this case, since the compatibility with the component (A) (particularly the hydrogenated styrene elastomer) is excellent, the resin composition (a) tends not to be clouded.

  In one embodiment, the content of the component (D) may be 0.3 to 20% by mass with respect to the total amount of the component (A), the component (B), the component (C), and the component (D). .

  In one aspect, a circuit board device is a film-like resin that is provided on a main surface of a circuit board on which a cured product of the resin composition (a) is formed so as to cover an electronic member and has elasticity after curing. A cured product of the composition (b) is further provided. In this aspect, since the stretched cured product (cured product of the resin composition (b)) covers the electronic member, the occurrence of problems due to the stress (for example, peeling and cracking of electronic components, cutting of wiring, etc.). There is a tendency to be less likely to occur. Furthermore, the cured product of the resin composition (b) protects the electronic member from contaminants such as dust and water.

  In one embodiment, the resin composition (b) may be a resin composition containing (A ′) a styrenic elastomer, (F) a polymerizable compound, and (E ′) a polymerization initiator. Since this film-like resin composition (b) is excellent in stretchability and adhesion, in this embodiment, the occurrence of problems due to the stress (for example, peeling and cracking of electronic components, cutting of wiring, etc.) is further suppressed. Tend to be. Moreover, there exists a tendency for the connection reliability of a circuit board apparatus to improve further by using the said film-form resin composition (b).

  In one embodiment, the component (E ′) may be a radical photopolymerization initiator. In this case, in addition to being able to cure at room temperature, the workability is excellent because the curing speed is high.

  In one embodiment, the content of the component (A ′) is 50 to 90% by mass with respect to the total amount of the component (A ′) and the component (F), and the content of the component (F) is (A ′ ) Component and the total amount of component (F) are 10 to 50% by mass, and the content of component (E ′) is based on 100 parts by mass of component (A ′) and component (F). It may be 0.1 to 10 parts by mass.

  ADVANTAGE OF THE INVENTION According to this invention, while being excellent in connection reliability, even when the stress by bending and a tension | tensile_strength is added, the circuit board apparatus which does not produce a malfunction easily can be provided.

FIG. 1 is a cross-sectional view showing an example of a circuit board device according to the first embodiment. FIG. 2 is a cross-sectional view showing an example of the circuit board device according to the first embodiment. FIG. 3 is a cross-sectional view showing an example of the circuit board device according to the first embodiment. FIG. 4 is a top view showing an example of the circuit board device according to the first embodiment. FIG. 5 is a top view showing an example of the circuit board device according to the first embodiment. FIG. 6 is a cross-sectional view showing a sealed state of the electronic member in one embodiment. FIG. 7 is a cross-sectional view showing a sealed state of the electronic member in one embodiment. FIG. 8 is a cross-sectional view showing a sealed state of the electronic member in one embodiment. FIG. 9 is a cross-sectional view showing an example of a circuit board device according to the second embodiment. FIG. 10 is a cross-sectional view showing an example of a circuit board device according to the second embodiment. FIG. 11 is a cross-sectional view showing an example of a circuit board device according to the second embodiment. FIG. 12 is a cross-sectional view showing an example of a circuit board device according to the second embodiment. FIG. 13 is a top view showing an example of a circuit board device according to the second embodiment. FIG. 14 is a cross-sectional view showing a method for manufacturing a circuit board device of the present invention. FIG. 15 is a top view showing a method for manufacturing a circuit board device of the present invention. FIG. 16 is a cross-sectional view showing a cutting step in the method for manufacturing a circuit board device of the present invention. FIG. 17 is a diagram showing a measurement example of the expansion / contraction recovery rate of the cured resin (a) and the cured resin (b) according to the present embodiment. FIG. 18 is a diagram showing a state of measurement of the expansion / contraction recovery rate of the deformable circuit board on which the cured resin (a) according to the present embodiment is provided on the main surface. FIG. 19 is a diagram illustrating a circuit board D in the embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions may be omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Furthermore, for convenience of illustration, the dimensional ratios in the drawings do not necessarily match those described.

<First embodiment>
1-3 are sectional views showing a circuit board device according to the first embodiment, and FIGS. 4 and 5 are top views showing the circuit board device according to the first embodiment. As shown in FIGS. 1 to 5, a circuit board device (semiconductor device) 50 according to the present embodiment includes a deformable circuit board 4 and an electronic member (including a semiconductor element) provided on the main surface of the circuit board 4. And a cured product 1 of the resin composition (a) 5 that seals the electronic member 3 (hereinafter also referred to as “resin cured product (a)”). In such a circuit board device, the stretch recovery rate after curing of the resin composition (a) 5 is 80% or more. That is, the stretch recovery rate of the cured resin (a) is 80% or more. 1 to 5, the electronic member 3 is an electronic component including a semiconductor element, but the electronic member 3 may be a wiring (except for a deformable wiring).

  The circuit board device 50 according to the present embodiment is excellent in connection reliability by including the above configuration. Further, even when stress due to bending or pulling is applied, defects (for example, peeling and cracking of electronic components, cutting of wiring, etc.) are unlikely to occur. Further, in the circuit board device 50 according to the present embodiment, even when stress due to torsion is applied, defects (for example, peeling and cracking of electronic components, cutting of wiring, etc.) are unlikely to occur.

  In the circuit board device 50 according to the present embodiment, the thickness of the layer made of the cured resin (a) 1 (height from the surface of the circuit board 4) may be uniform on the circuit board 4 and is not uniform. It may be. For example, as shown in FIG. 1, the cured resin (a) 1 is provided in accordance with the height of each electronic member 3 (height from the surface of the circuit board 4). The side opposite to the circuit board 4 of the layer made of may have irregularities, and as shown in FIGS. 2 and 3, the side opposite to the circuit board 4 of the layer made of the cured resin (a) 1 The surface may be a uniform plane. When the thickness of the layer made of the cured resin (a) 1 is uniform on the circuit board, the thickness of the layer made of the cured resin (a) 1 is the highest electronic member 3 as shown in FIG. And may be higher than the highest electronic member 3 as shown in FIG. The thickness of the layer made of the cured resin (a) 1 may be, for example, 0.1 μm to 4 mm. When the thickness is 0.1 μm or more, the layer made of the cured resin (a) 1 can maintain the shape of the film. When the thickness is 4 mm or less, it can be uniformly cured, and even if there is a difference between the inner and outer diameters when deformed by bending, the stress can be sufficiently relaxed, and the stress required for pulling does not need to be increased.

  In the circuit board device 50 according to the present embodiment, the cured resin (a) 1 covers the bottom part (pin part on the circuit board 4 side) and the side surface of the electronic component 3 as shown in FIG. As shown in FIG. 7, the electronic member 3 may be provided so as to cover the entire surface. In FIGS. 6 and 7, reference numerals 30 to 36 denote electronic members. Specifically, reference numeral 30 indicates a sensor, reference numeral 31 indicates an SOP (Small Outline Package), reference numerals 32-34 and 36 indicate an LED, a multilayer ceramic capacitor (capacitor), a fixed inductor, a multilayer chip EMC filter, or A surface mount component such as a square chip resistor is shown, and a reference numeral 35 denotes an IC package such as BGA (Ball Grid Array) or CSP (Chip Size / Scale Package). Reference numeral 41 denotes FPC (Flexible Printed Circuit). Reference numeral 7 denotes an underfill material.

  When the electronic member 3 is mounted on both main surfaces of the circuit board 4, the cured resin (a) 1 is mounted on both main surfaces of the circuit board 4 as shown in FIGS. 6 and 7. It may be provided so as to cover the electronic member 3. Moreover, as shown in FIG. 8, the cured resin (a) 1 may be provided in a portion where the electronic member 3 is not provided. Thereby, the thickness of the layer which consists of resin hardened | cured material (a) 1 increases, and an expansion-contraction recovery rate further improves. Further, by covering the entire surface (surface and side surfaces) of the circuit board 4 with the cured resin (a) 1, the electronic member 3 can be protected from water, dust and the like. If the cured resin (a) 1 having a low moisture absorption rate and moisture permeability is used, the waterproof property is improved, and the entire circuit board can be washed. Further, as shown in FIG. 4, the cured resin (a) 1 may be provided only on at least a part of the main surface of the circuit board 4, or may be provided on the entire main surface of the circuit board 4. Good. For example, the cured resin (a) 1 may be provided only on the electronic member 3 and its peripheral portion. Moreover, when the circuit board 4 has a deformable wiring, the wiring may be sealed with the cured resin (a) 1.

  The circuit board 4 is a circuit board that can be deformed by bending and pulling. The circuit board 4 may be a circuit board that can be deformed by twisting. For example, an FPC circuit board that can be twisted and bent, an FPC circuit board that is structurally devised so that it can expand and contract itself (for example, an FPC circuit board having a meander structure shown in FIG. 5), and a sheet shape that has elasticity A stretchable circuit board having a configuration in which a stretchable wiring is provided on the base material.

  As a constituent material of the circuit board 4, polyethylene terephthalate (PET) resin, polyethylene nitrile (PEN) resin, polyimide resin, epoxy resin, acrylic resin, urethane resin, silicone resin, polyethylene glycol resin, bismaleimide resin, and the like according to the purpose Are used as appropriate. The constituent material of the circuit board 4 is a polyimide resin having a siloxane structure, an aliphatic ether structure, or a diene structure; an acrylic resin; a silicone resin; a long-chain alkyl group (from the point that the circuit board 4 is excellent in stretchability and flexibility. For example, it may be one selected from the group consisting of a bismaleimide resin having an alkyl group having 5 to 20 carbon atoms; an epoxy resin; and a polyethylene glycol resin having a rotaxane structure. These can be used individually by 1 type or in combination of 2 or more types. Of these resins, a resin having a tensile elastic modulus at 25 ° C. of 5 MPa or less is preferable from the viewpoint of excellent stretchability and flexibility. Polyimide resins and epoxy resins having a tensile elastic modulus at 25 ° C. of 5 MPa or more are advantageous in terms of a large number of flexing resistances and a small thermal expansion coefficient, although they are inferior in stretchability and flexibility.

  The tensile elastic modulus at 25 ° C. of the circuit board 4 is preferably 3 Mpa or more from the viewpoint of excellent mechanical properties, particularly toughness and wear resistance, and capable of thinning even in applications where strength is required. In the case of deformation, it is preferably less than 3 Mpa from the viewpoint of less stress especially when expanding and contracting.

  In the present embodiment, the circuit board 4 may have wiring that can be deformed by twisting, bending, pulling, or the like on at least one main surface. When the circuit board 4 has a deformable wiring (wiring portion), the conductive material that is the wiring portion does not necessarily have to be stretchable, and the wiring shape is devised (for example, the wiring is thinned). In addition, the width of the circuit board is narrowed, and it is only necessary to be able to follow deformation due to a force such as twisting, bending, and pulling by a zigzag structure, a meander structure, or a spiral structure.

  When an electronic component is mounted as the electronic member 3, one type of electronic component may be mounted, or two or more types may be mixed and mounted. Further, one electronic component may be mounted, or a plurality of electronic components may be mounted. The height of the plurality of electronic components may be the same or different. The electronic component is a mounting component including semiconductor elements such as a light emitting diode (LED), a memory chip, a temperature sensor, an acceleration sensor, an NMOS, a PMOS, a coil (reference numeral 11 in FIG. 5), a battery, a switch, a diode, and a capacitor. It's okay.

  The liquid resin composition (a) 5 according to this embodiment is liquid at 25 ° C. Here, “liquid” means that the value of the viscosity of the resin composition maintained at 25 ° C. measured with an E-type viscometer at 0.5 rpm is 1000 Pa · s or less. The viscosity of the resin composition (a) 5 may be, for example, 1 mPa · s to 1000 Pa · s, or 20 mPa · s to 200 Pa · s.

  The liquid resin composition (a) 5 according to this embodiment has a stretch recovery rate after curing of 80% or more. The expansion / contraction recovery rate is determined in a tensile test using a cured resin (a) obtained by curing the liquid resin composition (a) 5 as a measurement sample. Specifically, the strain (displacement) applied in the first tensile test is X, and the difference between X and the position at which the load starts when the tensile test is performed again after returning to the initial position is Y. Then, R calculated by the formula: R (%) = Y / X × 100 is defined as the expansion / contraction recovery rate. In the present embodiment, the expansion / contraction recovery rate is a value measured when X is 50%. FIG. 17 shows a measurement example of the expansion / contraction recovery rate. If the expansion / contraction recovery rate is 80% or more, malfunctions (for example, peeling and cracking of electronic components, disconnection of wiring, etc.) will not occur even when stress due to twisting, bending, pulling, etc. is applied, and it will return to its original state after expansion / contraction. Can withstand repeated use. From such a viewpoint, the expansion / contraction recovery rate is more preferably 85% or more, and further preferably 90% or more.

  FIG. 18 shows the measurement of the expansion / contraction recovery rate of a circuit board (deformable circuit board) on which the cured resin (a) is provided on the main surface. When the stretch recovery rate of the cured resin itself is 80% or more, even when the circuit board is stretched, the circuit board is also returned by the return force of the cured resin, so that it can withstand repeated use. It also looks good.

  The liquid resin composition (a) 5 according to this embodiment is preferably a resin composition that is cured by irradiation with actinic rays such as ultraviolet rays or heating. When the resin composition (a) is a resin composition that is cured by heating, it is preferably a resin composition that is cured at a low temperature from the viewpoint of the heat resistance of the electronic member 3 (for example, an electronic component). The resin composition (a) 5 is preferably photocurable from the viewpoint that it can be cured at room temperature. Specifically, for example, (A) a styrene elastomer (hereinafter also referred to as “(A) component”) and (B) a monofunctional (meth) acrylate having an alkyl chain (hereinafter referred to as “(B) component”). And (C) a monofunctional (meth) acrylate having an alicyclic skeleton (hereinafter also referred to as “(C) component”), and (D) 2 having two or more ethylenically unsaturated groups. It may be a resin composition containing a functional or higher compound (hereinafter also referred to as “component (D)”) and (E) a polymerization initiator (hereinafter also referred to as “component (E)”). In this case, the resin cured product (a) obtained by curing the resin composition is excellent in stretchability and adhesion, and the connection reliability of the circuit board device tends to be further improved.

[(A) component]
Styrenic elastomer means an elastomer having a styrene skeleton. For example, it may be a copolymer containing polystyrene as a hard segment and a diene elastomer containing an unsaturated double bond as a soft segment.

  The diene elastomer is selected from, for example, polyethylene, polybutylene, and polyisoprene.

  Examples of commercially available styrene elastomers include “Dynalon SEBS Series” manufactured by JSR Corporation, “Clayton D Polymer Series” manufactured by Kraton Polymer Japan Co., Ltd., and “AR Series” manufactured by Aron Kasei Co., Ltd. is there.

  Styrene elastomer is a hydrogen adduct of diene elastomer (double bond by hydrogenation) formed by adding hydrogen to the hard segment polystyrene and unsaturated bond (double bond) of the diene elastomer. May be a diene elastomer saturated with a diene elastomer). In the present specification, a styrene elastomer whose soft segment is a hydrogenated product of the diene elastomer is referred to as a hydrogenated styrene elastomer. When the styrene elastomer is a hydrogenated styrene elastomer, more excellent effects can be expected in terms of weather resistance and the like.

  Hydrogenated styrene elastomers are, for example, “Dynalon HSBR Series” manufactured by JSR Corporation, “Clayton G Polymer Series” manufactured by Kraton Polymer Japan Co., Ltd., “Tough Tech Series” manufactured by Asahi Kasei Corporation, and Kuraray Co., Ltd. The “Septon series” manufactured by the company is suitable. Specifically, hydrogenated styrene isoprene copolymer (made by Kuraray Co., Ltd., trade name “Septon 2002”), hydrogenated styrene butadiene copolymer (made by Kraton Polymer Japan Co., Ltd., trade name “Clayton MD6951”). ), Hydrogenated styrene butadiene rubber (manufactured by JSR Corporation, trade name “Dynalon 2324P”).

  The weight average molecular weight of the styrene elastomer is preferably 30,000 to 200,000, more preferably 50,000 to 150,000, from the viewpoint of coating properties. A weight average molecular weight (Mw) can be calculated | required from the standard polystyrene conversion value by a gel permeation chromatography (GPC).

  It is preferable that content of (A) component is 10-50 mass% with respect to the total amount of (A) component, (B) component, (C) component, and (D) component, and 20-40 mass%. It is more preferable that When the content of the component (A) is 10% by mass or more, the stretchability tends to be sufficient, and the stretchability tends to be remarkably improved. (A) When content of a component is 50 mass% or less, since a viscosity does not become high too much, it is easy to perform a coating operation.

[Component (B)]
The monofunctional (meth) acrylate having an alkyl chain is an ester compound having one (meth) acryloyl group and a linear or branched alkyl group.

  Examples of the monofunctional (meth) acrylate having an alkyl chain include isooctyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, isostearyl acrylate, stearyl acrylate and tridecyl acrylate. These compounds can be used alone or in combination of two or more, and can also be used in combination with other polymerizable compounds.

  (B) Carbon number of the alkyl chain in component is preferably 12 or less, more preferably 10 or less. When the number of carbon atoms is 12 or less, the resin composition (a) 5 is not easily clouded because of excellent compatibility with styrene elastomers (particularly hydrogenated styrene elastomers). Examples of such component (B) include isooctyl (meth) acrylate, isodecyl (meth) acrylate, and lauryl (meth) acrylate.

  The content of the component (B) is preferably 10 to 50% by mass with respect to the total amount of the components (A), (B), (C) and (D), and 20 to 40% by mass. It is more preferable that When content of (B) component is 10 mass% or more, resin contained in resin hardened | cured material (a) cannot become rigid easily. For this reason, the elastic modulus of the cured resin (a) is hardly increased and the stretchability tends to be remarkably improved. When content of (B) component is 50 mass% or less, there exists a tendency for it to be excellent in adhesiveness.

[Component (C)]
Examples of the monofunctional (meth) acrylate having an alicyclic skeleton include cyclohexyl acrylate, 3,3,5-trimethylcyclohexanol (meth) acrylate, 4-tert-butylcyclohexanol (meth) acrylate, Examples include bornyl acrylate, tricyclodecyl acrylate and tetrahydrofurfuryl acrylate. These compounds can be used alone or in combination of two or more, and can also be used in combination with other polymerizable compounds.

  The content of the component (C) is preferably 10 to 50% by mass with respect to the total amount of the components (A), (B), (C) and (D), and 20 to 40% by mass. It is more preferable that (C) When content of a component is 10 mass% or more, there exists a tendency for adhesiveness to improve remarkably. When content of (C) component is 50 mass% or less, resin contained in resin hardened | cured material (a) cannot become rigid easily. For this reason, the elastic modulus of the cured resin (a) is hardly increased and the stretchability tends to be remarkably improved.

[(D) component]
Examples of the bifunctional or higher functional compound having two or more ethylenically unsaturated groups (excluding compounds corresponding to the component (A)) include (meth) acrylate, vinylidene halide, vinyl ether, vinyl ester, vinyl pyridine, Vinylamide and arylated vinyl are mentioned. Among these, from the viewpoint of the transparency of the cured resin (a), at least one of (meth) acrylate and arylated vinyl is preferable.

  Examples of the bifunctional (meth) acrylate having two (meth) acryloyl groups include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di ( (Meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, polypropylene glycol di (Meth) acrylate, ethoxylated polypropylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanedio Di (meth) acrylate, neopentyl glycol di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 2-butyl-2-ethyl -1,3-propanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, glycerin di (meth) acrylate, tricyclodecane dimethanol ( Aliphatic (meth) acrylates such as meth) acrylate and ethoxylated 2-methyl-1,3-propanediol di (meth) acrylate; cyclohexanedimethanol (meth) acrylate, ethoxylated cyclohexanedimethanol (meth) acrylate, propoxylation Cyclohexane Dime Nord (meth) acrylate, ethoxylated propoxylated cyclohexanedimethanol (meth) acrylate, tricyclodecane dimethanol (meth) acrylate, ethoxylated tricyclodecane dimethanol (meth) acrylate, propoxylated tricyclodecane dimethanol (meth) Acrylate, ethoxylated propoxylated tricyclodecanedimethanol (meth) acrylate, ethoxylated hydrogenated bisphenol A di (meth) acrylate, propoxylated hydrogenated bisphenol A di (meth) acrylate, ethoxylated propoxylated hydrogenated bisphenol A di ( (Meth) acrylate, ethoxylated hydrogenated bisphenol F di (meth) acrylate, propoxylated hydrogenated bisphenol F di (meth) acrylate, ethoxylated propoxylated hydrogenated bisphenol F-aliphatic (meth) acrylates such as di (meth) acrylate; ethoxylated bisphenol A di (meth) acrylate, propoxylated bisphenol A di (meth) acrylate, ethoxylated propoxylated bisphenol A di (meth) acrylate, ethoxy Bisphenol F di (meth) acrylate, propoxylated bisphenol F di (meth) acrylate, ethoxylated propoxy bisphenol F di (meth) acrylate, ethoxylated bisphenol AF di (meth) acrylate, propoxylated bisphenol AF di (meth) acrylate , Ethoxylated propoxylated bisphenol AF di (meth) acrylate, ethoxylated fluorene di (meth) acrylate, propoxylated fluorene di (meth) acrylate, ethoxylated propo Aromatic (meth) acrylates such as silylated fluorene di (meth) acrylate; ethoxylated isocyanuric acid di (meth) acrylate, propoxylated isocyanuric acid di (meth) acrylate, ethoxylated propoxylated isocyanuric acid di (meth) acrylate, etc. Heterocyclic (meth) acrylates; modified caprolactones thereof; aliphatic epoxy (meth) acrylates such as neopentyl glycol type epoxy (meth) acrylate; cyclohexanedimethanol type epoxy (meth) acrylate, hydrogenated bisphenol A type epoxy Aliphatic epoxy (meth) acrylate such as (meth) acrylate, hydrogenated bisphenol F type epoxy (meth) acrylate; resorcinol type epoxy (meth) acrylate, bisphenol A type epoxy (meth) acrylate Relate, bisphenol F type epoxy (meth) acrylate, bisphenol AF type epoxy (meth) acrylates, and aromatic epoxy (meth) acrylates such as fluorene epoxy (meth) acrylate.

  Examples of the trifunctional or higher polyfunctional (meth) acrylate having 3 or more (meth) acryloyl groups include trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, and propoxylated trimethylolpropane. Tri (meth) acrylate, ethoxylated propoxylated trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethoxylated pentaerythritol tri (meth) acrylate, propoxylated pentaerythritol tri (meth) acrylate, ethoxylated propoxy Pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, ethoxylated pentaerythritol tetra (meth) acrylate, Aliphatic (meth) acrylates such as poxylated pentaerythritol tetra (meth) acrylate, ethoxylated propoxylated pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol hexa (meth) acrylate; ethoxylated isocyanuric acid tri Heterocyclic (meth) acrylates such as (meth) acrylate, propoxylated isocyanuric acid tri (meth) acrylate and ethoxylated propoxylated isocyanuric acid tri (meth) acrylate; modified caprolactone thereof; phenol novolac-type epoxy (meth) acrylate And aromatic epoxy (meth) acrylates such as cresol novolac type epoxy (meth) acrylate.

  Among these, cyclohexanedimethanol (meth) acrylate, tricyclodecanedi from the viewpoints of compatibility with styrene elastomer, transparency and heat resistance of the cured resin (a), and adhesion to polyimide and copper foil. A (meth) acrylate having an alicyclic structure such as methanol (meth) acrylate is preferred. These compounds can be used alone or in combination of two or more, and can also be used in combination with other polymerizable compounds.

  The content of the component (D) is preferably 0.3 to 20% by mass with respect to the total amount of the components (A), (B), (C) and (D), and 0.5 More preferably, it is 10 mass%, More preferably, it is 1-5 mass%. When content of (D) component is 0.3 mass% or more, since it can fully harden | cure, tackiness does not remain easily and there exists a tendency for a stretching property to improve remarkably. When content of (D) component is 20 mass% or less, resin contained in resin hardened | cured material (a) does not become rigid easily. For this reason, the elastic modulus of the cured resin (a) is hardly increased and the stretchability tends to be remarkably improved.

[(E) component]
The polymerization initiator is not particularly limited as long as it initiates polymerization by heating or irradiation with actinic rays such as ultraviolet rays. For example, the components (B), (C) and (D) When (meth) acrylate is used, a thermal radical polymerization initiator and photoradical polymerization initiation are exemplified. The component (E) is preferably a radical photopolymerization initiator because the curing speed is high and room temperature curing is possible.

  Examples of the thermal radical polymerization initiator include ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, and methylcyclohexanone peroxide; 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t- Butylperoxy) -2-methylcyclohexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1- Peroxyketals such as bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane; hydroperoxides such as p-menthane hydroperoxide; α, α′-bis (t-butylperoxy) diisopropylbenzene , Dicumyl peroxide, t-butylcumylperoxy Dialkyl peroxides such as di- and t-butyl peroxide; diacyl peroxides such as octanoyl peroxide, lauroyl peroxide, stearyl peroxide and benzoyl peroxide; bis (4-t-butylcyclohexyl) peroxydicarbonate Peroxycarbonates such as di-2-ethoxyethyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-3-methoxybutyl peroxycarbonate; t-butyl peroxypivalate, t-hexyl peroxy Pivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane, t-hexylper Oxy-2-ethylhexano Tate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanoate , T-butyl peroxylaurate, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-butyl peroxybenzoate, t-hexyl peroxybenzoate, 2,5-dimethyl- Peroxyesters such as 2,5-bis (benzoylperoxy) hexane and t-butylperoxyacetate; 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile) ), 2,2′-azobis (4-methoxy-2′-) Such as methyl valeronitrile) and azo compounds, and the like. Among these, from the viewpoints of the curability of the resin composition (a) 5 and the transparency and heat resistance of the resin cured product (a), selected from the group consisting of the diacyl peroxide, peroxy ester and azo compound. It is preferable that it is at least one kind.

  Examples of the photo radical polymerization initiator include benzoinketals such as 2,2-dimethoxy-1,2-diphenylethane-1-one; 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane Α-hydroxy ketones such as -1-one and 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one; 2-benzyl-2-dimethylamino- Α-amino ketones such as 1- (4-morpholinophenyl) -butan-1-one and 1,2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one; Oxime esters such as [4- (phenylthio) phenyl] -1,2-octadion-2- (benzoyl) oxime; bis (2,4,6-tri Phosphine oxides such as methylbenzoyl) phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 2- (o-chlorophenyl) ) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer 2,4,5-triaryl such as 2-mer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer Imidazole dimer; benzophenone, N, N, N ′, N′-tetramethyl-4, Benzophenone compounds such as '-diaminobenzophenone, N, N, N', N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone; 2-ethylanthraquinone, phenanthrenequinone, 2- tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone Quinone compounds such as 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone and 2,3-dimethylanthraquinone; benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether Benzoin ethers such as benzoin; benzoin compounds such as benzoin, methylbenzoin and ethylbenzoin; benzyl compounds such as benzyldimethyl ketal; acridines such as 9-phenylacridine and 1,7-bis (9,9′-acridinylheptane) Compound: N-phenylglycine, coumarin and the like can be mentioned.

  In the 2,4,5-triarylimidazole dimer, the aryl group substituents of the two triarylimidazole moieties may give the same and symmetric compound, or differently give the asymmetric compound. Good. Also. A thioxanthone compound and a tertiary amine may be combined, such as a combination of diethylthioxanthone and dimethylaminobenzoic acid.

  From the viewpoints of the curability of the resin composition (a) 5 and the transparency and heat resistance of the cured resin (a), the radical photopolymerization initiator is at least one of the α-hydroxyketone and the phosphine oxide. It is preferable that These thermal and photo radical polymerization initiators can be used alone or in combination of two or more. Furthermore, it can also be used in combination with an appropriate sensitizer.

  It is preferable that content of (E) component is 0.1-10 mass parts with respect to 100 mass parts of total amounts of (A) component, (B) component, (C) component, and (D) component. When the content of the component (E) is 0.1 parts by mass or more, curing tends to be sufficient, and when the content of the component (E) is 10 parts by mass or less, sufficient light transmittance is obtained. It is easy to be done. From these viewpoints, the content of the component (E) is more preferably 0.3 to 7 parts by mass, and further preferably 0.5 to 5 parts by mass.

  If necessary, the liquid resin composition (a) 5 may contain an antioxidant, a yellowing inhibitor, a UV absorber, a visible light absorber, a colorant, a plasticizer, and a stabilizer in addition to the components described above. In addition, so-called additives such as fillers may be contained in proportions that do not adversely affect the effects of the present invention.

  The liquid resin composition (a) 5 according to this embodiment may be a resin varnish diluted with a suitable organic solvent. The organic solvent is not particularly limited as long as it can dissolve the resin composition (a) 5. For example, aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene, p-cymene; tetrahydrofuran, 1, 4 -Cyclic ethers such as dioxane; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone; methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone And esters such as ethylene carbonate and propylene carbonate; and amides such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone. Among these, from the viewpoints of solubility and boiling point, at least one of toluene and N, N-dimethylacetamide is preferable. These organic solvents can be used alone or in combination of two or more. It is preferable that the solid content concentration in the resin varnish is usually 20 to 80% by mass.

  The elastic modulus of the cured resin (a) according to this embodiment is preferably 0.1 MPa or more and 100 MPa or less, more preferably 0.2 MPa or more and 50 MPa or less, and 0.3 MPa or more and 30 MPa or less. Is more preferable. When the elastic modulus is 0.1 MPa or more, the problem that the cured resin products stick to each other due to blocking is unlikely to occur. When the elastic modulus is 100 MPa or less, the resin contained in the cured resin (a) is difficult to be rigid. Therefore, there exists a tendency for the softness | flexibility and elasticity of resin cured | curing material (a) to become more enough.

  The elongation at break of the cured resin (a) is preferably 100% or more. If it is 100% or more, more sufficient stretchability can be obtained. The elongation at break is more preferably 150% or more, and further preferably 200% or more.

  The resin cured product (a) according to this embodiment has a total light transmittance of 80% or more measured with a spectral haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., spectral haze meter “SH7000”), and a yellowness index (YI) of 5 0.0 or less and haze is preferably 5.0% or less. If it is in this range, sufficient transparency can be obtained. More preferably, the total light transmittance is 85% or more, the Yellowness Index is 4.0 or less, and the haze is 4.0% or less, the total light transmittance is 90% or more, the Yellowness Index is 3.0 or less, and the haze is More preferably, it is 3.0% or less.

<Second embodiment>
9 to 12 are cross-sectional views showing the circuit board device according to the second embodiment, and FIG. 13 is a top view showing the circuit board device according to the second embodiment. As shown in FIGS. 9 to 13, a circuit board device (semiconductor device) 100 according to this embodiment includes a deformable circuit board 4 and an electronic member (including a semiconductor element) provided on the main surface of the circuit board 4. The electronic component 3, the cured resin (a) 1 that seals the electronic member 3, and the main surface of the circuit board on which the cured resin (a) 1 is formed are provided so as to cover the electronic member 3. Further, a cured product 2 of a film-like resin composition (b) 6 having stretchability after curing (hereinafter also referred to as “resin cured product (b)”) is provided.

  In the circuit board device 100 according to the present embodiment, the electronic member is also covered with the cured resin (b). Therefore, according to the present embodiment, defects due to the stress (for example, peeling and cracking of electronic components, wiring) Occurrence of cutting or the like) is less likely to occur.

  Hereinafter, features unique to the second embodiment of the present invention will be mainly described. Except for the matters described below, the second embodiment is the same as the first embodiment. Hereinafter, common points between the second embodiment and the first embodiment will not be described.

  In the circuit board device 100 according to the present embodiment, the cured resin (b) may be provided on the entire main surface of the circuit board 4 as shown in FIG. It may be provided only in. For example, the cured resin (b) may be provided only on the electronic member 3 sealed with the cured resin (a) and on the peripheral portion thereof. In the circuit board device 100 according to the present embodiment, the distance from the surface of the circuit board 4 to the surface of the layer made of the resin cured product (b) 2 opposite to the circuit board 4 is on the circuit board 4. It may be uniform or non-uniform. For example, as shown in FIG. 9, the surface opposite to the circuit board 4 of the layer made of the cured resin (b) 2 may have unevenness, and the cured resin as shown in FIGS. (B) The surface opposite to the circuit board 4 of the layer made of 2 may be a flat surface. In addition, the cured resin (a) 1 and the cured resin (b) 2 may be provided in a portion where the electronic member 3 is not provided. Thereby, the thickness of the layer which consists of resin hardened | cured material (a) 1 and resin hardened | cured material (b) 2 increases, and an expansion-contraction recovery rate further improves. Further, by covering the entire surface of the circuit board 4 with the cured resin (a) 1 and the cured resin (b) 2, the electronic member 3 can be protected from water, dust and the like. If the cured resin (a) 1 and cured resin (b) 2 having a low moisture absorption rate and moisture permeability are used, the waterproof property is improved and the circuit board can be washed together. A polymer having a low molecular weight, a hydrophilic group, or a small number of C—C bonds (for example, having a Si—O bond or a C—O bond instead of a C—C bond) has a high moisture permeability. Tend.

  The film-like resin composition (b) 6 is a resin composition having elasticity after curing. The film-like resin composition (b) 6 is preferably a resin composition that is cured by irradiation with actinic rays such as ultraviolet rays or heating. Specifically, for example, (A ′) a styrene-based elastomer (hereinafter also referred to as “(A ′) component”), (F) a polymerizable compound (hereinafter also referred to as “(F) component”), ( It may be a resin composition containing E ′) a polymerization initiator (hereinafter also referred to as “component (E ′)”).

[(A ′) component]
Specific examples of the component (A ′) are the same as the component (A) described above. It is preferable that content of (A ') component is 50-90 mass% with respect to the total amount of (A') component and (F) component. When the content of the component (A ′) is 50% by mass or more, the stretchability after curing tends to be sufficient. When the content of the component (A ′) is 90% by mass or less, there is a tendency to be easily entangled by the component (F) during exposure. From the above viewpoint, the content of the component (A ′) is more preferably 55 to 85% by mass, and further preferably 60 to 80% by mass.

[(E ′) component]
Specific examples of the component (E ′) are the same as the component (E) described above. It is preferable that content of (E ') component is 0.1-10 mass parts with respect to 100 mass parts of total amounts of (A') component and (F) component. When the content of the component (E ′) is 0.1 part by mass or more, curing is likely to be sufficient. When the content of the component (E ′) is 10 parts by mass or less, sufficient light transmittance is easily obtained. From the above viewpoint, the content of the component (E ′) is more preferably 0.3 to 7 parts by mass, and further preferably 0.5 to 5 parts by mass.

[(F) component]
The polymerizable compound is not particularly limited as long as it is polymerized by heating or irradiation with actinic rays such as ultraviolet rays, but from the viewpoint of material selectivity and availability, for example, polymerization of ethylenically unsaturated groups and the like. Preferred examples include compounds having an ionic substituent. Specific examples include (meth) acrylates, vinylidene halides, vinyl ethers, vinyl esters, vinyl pyridines, vinyl amides, and arylated vinyls. From the viewpoint of transparency, at least one of (meth) acrylate or arylated vinyl is preferable. As the (meth) acrylate, any of monofunctional, bifunctional, or polyfunctional ones can be used. From the viewpoint of obtaining sufficient curability, it is preferable to use a bifunctional or polyfunctional one.

  Examples of the monofunctional (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, butoxyethyl (meth) acrylate, Isoamyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, octylheptyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate , Lauryl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, stearyl (Meth) acrylate, behenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, Aliphatics such as methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, ethoxypolypropylene glycol (meth) acrylate, mono (2- (meth) acryloyloxyethyl) succinate ( (Meth) acrylate; cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, dicyclopentanyl (meth) Alicyclic rings such as acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, mono (2- (meth) acryloyloxyethyl) tetrahydrophthalate, mono (2- (meth) acryloyloxyethyl) hexahydrophthalate Formula (meth) acrylate; benzyl (meth) acrylate, phenyl (meth) acrylate, o-biphenyl (meth) acrylate, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, phenoxyethyl (meth) acrylate, p -Cumylphenoxyethyl (meth) acrylate, o-phenylphenoxyethyl (meth) acrylate, 1-naphthoxyethyl (meth) acrylate, 2-naphthoxyethyl (meth) acrylate, phenoxypolyethylene glycol (Meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, phenoxypolypropylene glycol (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-hydroxy-3- (o-phenylphenoxy) propyl (meta Aromatic (meth) acrylates such as acrylate, 2-hydroxy-3- (1-naphthoxy) propyl (meth) acrylate, 2-hydroxy-3- (2-naphthoxy) propyl (meth) acrylate; 2-tetrahydrofurfuryl Heterocyclic (meth) acrylates such as (meth) acrylate, N- (meth) acryloyloxyethyl hexahydrophthalimide, 2- (meth) acryloyloxyethyl-N-carbazole, modified caprolactone thereof, etc. And the like. Among these, at least one of the aliphatic (meth) acrylate and the aromatic (meth) acrylate from the viewpoints of compatibility with the styrene-based elastomer and transparency and heat resistance of the cured resin (b). It is preferable.

  Examples of the bifunctional (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, and polyethylene glycol di (meth) acrylate. , Propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, ethoxylated polypropylene glycol di ( (Meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, neopentyl Recall di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 2-butyl-2-ethyl-1,3-propanediol di ( (Meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, glycerin di (meth) acrylate, tricyclodecane dimethanol (meth) acrylate, ethoxylated 2-methyl Aliphatic (meth) acrylates such as 1,3-propanediol di (meth) acrylate; cyclohexanedimethanol (meth) acrylate, ethoxylated cyclohexanedimethanol (meth) acrylate, propoxylated cyclohexanedimethanol (meth) acrylate, ethoxy Propoxylated cyclohexanedimethanol (meth) acrylate, tricyclodecane dimethanol (meth) acrylate, ethoxylated tricyclodecane dimethanol (meth) acrylate, propoxylated tricyclodecane dimethanol (meth) acrylate, ethoxylated propoxylated tricyclo Decandimethanol (meth) acrylate, ethoxylated hydrogenated bisphenol A di (meth) acrylate, propoxylated hydrogenated bisphenol A di (meth) acrylate, ethoxylated propoxylated hydrogenated bisphenol A di (meth) acrylate, ethoxylated hydrogenated Alicyclic (such as bisphenol F di (meth) acrylate, propoxylated hydrogenated bisphenol F di (meth) acrylate, ethoxylated propoxylated hydrogenated bisphenol F di (meth) acrylate, etc. Meth) acrylate; ethoxylated bisphenol A di (meth) acrylate, propoxylated bisphenol A di (meth) acrylate, ethoxylated propoxylated bisphenol A di (meth) acrylate, ethoxylated bisphenol F di (meth) acrylate, propoxylated bisphenol F Di (meth) acrylate, ethoxylated propoxylated bisphenol F di (meth) acrylate, ethoxylated bisphenol AF di (meth) acrylate, propoxylated bisphenol AF di (meth) acrylate, ethoxylated propoxylated bisphenol AF di (meth) acrylate, Ethoxylated fluorene-type di (meth) acrylate, propoxylated fluorene-type di (meth) acrylate, ethoxylated propoxylated fluorene-type di (meth) acrylate Aromatic (meth) acrylates such as: heterocyclic (meth) acrylates such as ethoxylated isocyanuric acid di (meth) acrylate, propoxylated isocyanuric acid di (meth) acrylate, ethoxylated propoxylated isocyanuric acid di (meth) acrylate; These modified caprolactones; aliphatic epoxy (meth) acrylates such as neopentyl glycol type epoxy (meth) acrylate; cyclohexanedimethanol type epoxy (meth) acrylate, hydrogenated bisphenol A type epoxy (meth) acrylate, hydrogenated bisphenol F Type epoxy (meth) acrylate and other cycloaliphatic epoxy (meth) acrylates; resorcinol type epoxy (meth) acrylate, bisphenol A type epoxy (meth) acrylate, bisphenol F type epoxy Meth) acrylate, bisphenol AF type epoxy (meth) acrylates, and aromatic epoxy (meth) acrylates such as fluorene epoxy (meth) acrylate. Among these, at least one of the aliphatic (meth) acrylate and the aromatic (meth) acrylate from the viewpoints of compatibility with the styrene-based elastomer and transparency and heat resistance of the cured resin (b). It is preferable.

  Examples of the trifunctional or higher polyfunctional (meth) acrylate include trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, and ethoxylated propoxylated tri Methylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethoxylated pentaerythritol tri (meth) acrylate, propoxylated pentaerythritol tri (meth) acrylate, ethoxylated propoxylated pentaerythritol tri (meth) acrylate, pentaerythritol Tetra (meth) acrylate, ethoxylated pentaerythritol tetra (meth) acrylate, propoxylated pentaerythritol tetra (me ) Aliphatic (meth) acrylates such as acrylate, ethoxylated propoxylated pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol hexa (meth) acrylate; ethoxylated isocyanuric acid tri (meth) acrylate, propoxylated Heterocyclic (meth) acrylates such as isocyanuric acid tri (meth) acrylate and ethoxylated propoxylated isocyanuric acid tri (meth) acrylate; these caprolactone modified products; phenol novolac epoxy (meth) acrylate, cresol novolac epoxy (meta) ) Aromatic epoxy (meth) acrylate such as acrylate. Among these, at least one of the aliphatic (meth) acrylate and the aromatic (meth) acrylate from the viewpoints of compatibility with the styrene-based elastomer and transparency and heat resistance of the cured resin (b). It is preferable.

  These compounds can be used alone or in combination of two or more, and can also be used in combination with other polymerizable compounds.

  It is preferable that content of (F) component is 10-50 mass% with respect to the total amount of (A ') component and (F) component. When the content of the component (F) is 10% by mass or more, it tends to be easily cured together with the (A ′) styrenic elastomer. When the content of the component (F) is 50% by mass or less, the strength and stretchability of the cured resin (b) are likely to be sufficient. From the above viewpoint, the content of the component (F) is more preferably 15 to 40% by mass.

  The film-like resin composition (b) 6 may contain, in addition to the above-described components, an antioxidant, an anti-yellowing agent, an ultraviolet absorber, a visible light absorber, a colorant, a plasticizer, and a stability, as necessary. You may contain what is called additives, such as an agent and a filler, in the ratio which does not have a bad influence on the effect of this invention.

  The elastic modulus of the cured resin (b) is preferably from 0.1 MPa to 1000 MPa. If it is 0.1 MPa or more and 1000 MPa or less, it is excellent in the handleability as a film and the elasticity of the resin cured product (b). From this viewpoint, the elastic modulus is more preferably 0.3 MPa or more and 100 MPa or less, and further preferably 0.5 MPa or more and 50 MPa or less.

  The elongation at break of the cured resin (b) is preferably 100% or more. If it is 100% or more, sufficient stretchability can be obtained. From this viewpoint, the elongation at break is more preferably 300% or more, and further preferably 500% or more.

  The stretch recovery rate of the cured resin (b) is preferably 80% or more. The stretch recovery rate of the cured resin (b) is defined in the same manner as the stretch recovery rate of the cured resin (a) 1 and exhibits the same behavior as the cured resin (a) in the strain-stress relationship. An example is shown in FIG. If the expansion / contraction recovery rate is 80% or more, stress due to twisting, bending, pulling, etc. can be further relaxed, and it can withstand repeated use. For this reason, the expansion / contraction recovery rate is more preferably 85% or more, and still more preferably 90% or more.

  The cured resin (b) has a total light transmittance of 80% or more, a Yellowness Index of 5.0 or less, and a haze of 5. or less as measured with a spectral haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., spectral haze meter “SH7000”). It is preferably 0% or less. If it is in this range, sufficient transparency can be obtained. From this viewpoint, it is more preferable that the total light transmittance is 85% or more, the Yellowness Index is 4.0 or less, and the haze is 4.0% or less. The total light transmittance is 90% or more, and the Yellowness Index is 3.0. Hereinafter, the haze is more preferably 3.0% or less.

  The cured resin (b) is obtained by performing a 90 ° peel test (peeling speed 50 mm / min, sample width 10 mm) after laminating and curing the resin composition (b) 6 on a silicon substrate or a polyimide substrate. Furthermore, it is preferable to have an adhesion strength of 5 N / cm or more. The higher the adhesion strength is, the more practical it is. From this viewpoint, it is more preferably 7 N / cm, and further preferably 10 N / cm.

  The thickness of the film-like resin composition (b) 6 is not particularly limited, but the thickness after drying is preferably 5 to 1000 μm. When the thickness is 5 μm or more, the thickness is sufficient, and the strength of the film-shaped resin composition (b) 6 or the cured product of the film-shaped resin composition (b) 6 (resin cured product (b)) is sufficient. Yes, when the thickness is 1000 μm or less, the cured product of the film-like resin composition (b) 6 was heated without increasing the amount of residual solvent in the film-like resin composition (b) 6 because drying can be performed sufficiently. Sometimes it does not foam.

  The film-like resin composition (b) 6 according to the present embodiment is preferably a base film made of, for example, a resin varnish containing the component (A ′), the component (F), the component (E ′) and an organic solvent. It can manufacture easily by apply | coating to and removing a solvent. The resin film thus obtained can be easily stored, for example, by winding it into a roll. Alternatively, a roll-shaped film can be cut into a suitable size and stored in a sheet shape.

  The organic solvent is not particularly limited as long as it can dissolve the resin composition. For example, aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene and p-cymene; aliphatic carbonization such as hexane and heptane. Hydrogen; Cyclic alkanes such as methylcyclohexane; Cyclic ethers such as tetrahydrofuran and 1,4-dioxane; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone; Methyl acetate, acetic acid Esters such as ethyl, butyl acetate, methyl lactate, ethyl lactate and γ-butyrolactone; carbonates such as ethylene carbonate and propylene carbonate; amides such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone Can be mentionedAmong these, from the viewpoints of solubility and boiling point, it is preferably at least one selected from the group consisting of toluene, xylene, heptane and cyclohexane. These organic solvents can be used alone or in combination of two or more. It is preferable that the solid content concentration in the resin varnish is usually 20 to 80% by mass.

  The material constituting the base film is not particularly limited. For example, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefins such as polyethylene and polypropylene; polycarbonates, polyamides, polyimides, polyamideimides, polyetherimides , Polyether sulfide, polyether sulfone, polyether ketone, polyphenylene ether, polyphenylene sulfide, polyarylate, polysulfone, liquid crystal polymer, and the like. The materials constituting the base film are polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polypropylene, polycarbonate, polyamide, polyimide, polyamideimide, polyphenylene ether, polyphenylene sulfide, polyarylate or polysulfone from the viewpoints of flexibility and toughness. It is preferable that

  The thickness of the base film may be appropriately changed depending on the intended flexibility, but is preferably 3 to 250 μm. When it is 3 μm or more, the film strength is sufficient, and when it is 250 μm or less, sufficient flexibility is obtained. From the above viewpoint, the thickness is more preferably 5 to 200 μm, and further preferably 7 to 150 μm. In addition, from the viewpoint of improving releasability from the film-like resin composition (b) 6, a film that has been subjected to a release treatment with a silicone compound, a fluorine-containing compound, or the like may be used as necessary.

  A resin film produced by applying a resin varnish on a base film is applied with a protective film on the film-like resin composition (b) 6 as necessary, and the base film and the film-like resin composition ( b) It is good also as a 3 layer structure which consists of 6 and a protective film.

  The protective film is not particularly limited, and examples thereof include polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefins such as polyethylene and polypropylene. Among these, from the viewpoint of flexibility and toughness, polyesters such as polyethylene terephthalate; polyolefins such as polyethylene and polypropylene are preferable. In addition, from the viewpoint of improving releasability from the film-like resin composition (b) 6, a film that has been subjected to a release treatment with a silicone compound, a fluorine-containing compound, or the like may be used as necessary. The thickness of the protective film may be appropriately changed depending on the intended flexibility, but is preferably 10 to 250 μm. When it is 10 μm or more, the film strength is sufficient, and when it is 250 μm or less, sufficient flexibility is obtained. From the above viewpoint, the thickness is more preferably 15 to 200 μm, further preferably 20 to 150 μm.

  The film-like resin composition (b) 6 is suitable as a flexible substrate for wearable devices, an electric circuit protective layer, and a sealing resin, and particularly suitable as a resin sealing material for wearable devices. Similarly, the resin film according to the present embodiment is suitable as a flexible substrate for wearable devices, an electrical circuit protective layer, and a sealing film.

<Method for Manufacturing Circuit Board Device>
Next, a method for manufacturing the circuit board device according to the first embodiment and the second embodiment will be described.

  In the method for manufacturing the circuit board device 50 according to the first embodiment, the electronic member 3 is sealed by providing the liquid resin composition (a) 5 on the main surface of the circuit board 4 on which the electronic member 3 is provided. Sealing step (hereinafter also referred to as “first sealing step”) and a curing step (hereinafter referred to as “first”) in which the liquid resin composition (a) 5 is cured to obtain a cured resin (a) 1. Also referred to as “a single curing step”).

  In the above manufacturing method, since the resin composition (a) 5 is in a liquid state, the resin composition (a) 5 is on the circuit board due to electronic members (for example, electronic components, wirings, etc.) having various heights. Can follow the irregularities. Moreover, in the said manufacturing method, the level | step difference by the unevenness | corrugation on the circuit board 4 can be eased by apply | coating the liquid resin composition (a) 5 to the recessed part on the circuit board 4, and making it harden | cure. Therefore, the stress concentrated on the uneven portion can be relieved and the entire main surface of the circuit board 4 can be covered with a good appearance. Further, in the above manufacturing method, the stress applied when the circuit board 4 of the circuit board device 50 is expanded and contracted is further reduced by providing the resin composition only on the necessary part (for example, on the electronic member 3 and its peripheral part). can do.

  By the way, the present inventors also examined sealing an electronic member with a film-like resin composition (hereinafter also referred to as “resin composition film”). As a result, it has been clarified that the film-like resin composition cannot sufficiently fill fine pin portions (particularly on the substrate side) of electronic components such as QFP (Quad Flat Package) and SOP (Small Outline Package). . In addition, when the resin composition is usually flowed by heating and the resin composition is pasted with a laminator or the like, the thickness of the resin tends to be thin at the corners of the IC chip or the like, and depending on the thickness of the resin composition film In some cases, the resin composition film was torn. Although it is conceivable to increase the resin thickness of the film in order to prevent the film from tearing, in this case, the force required for bending and pulling (the force necessary to deform the film) increases, so this application Is not suitable. Further, according to the study by the present inventors, the resin composition film is usually obtained by applying a coating liquid to a substrate such as a PET (Polyethylene terephthalate) film using a coater such as a knife coater or a curtain coater, and then drying. Therefore, it is difficult to obtain a thick film (for example, a film having a thickness of 0.3 mm or more). In the method of manufacturing a circuit board device, problems caused by using such a film-like resin composition can be solved.

  In addition to the manufacturing method of the circuit board device 50 according to the first embodiment, the manufacturing method of the circuit board device 100 according to the second embodiment is a resin curing after the liquid resin composition (a) 5 is cured. On the main surface of the circuit board 4 on which the product (a) 1 is formed, a film-like resin composition (b) 6 having stretchability after being cured is pasted, and the electronic member 3 is attached together with the resin cured product (a). A step of coating (hereinafter also referred to as “second sealing step”) and a step of curing the film-like resin composition (b) 6 to obtain a cured resin (hereinafter referred to as “second curing step”). It is also provided.

  The method for manufacturing the circuit board device according to the first embodiment and the second embodiment may further include a mounting step of mounting an electronic member (for example, an electronic component) 3 on at least one main surface of the circuit board 4. A cutting step of obtaining a plurality of circuit board devices having the electronic member 3 by cutting and separating the circuit board 4 may be further provided.

  Hereinafter, details of each step will be described with reference to the drawings. Hereinafter, as an example of the method for manufacturing the circuit board device according to the present embodiment, a method for manufacturing a semiconductor device including an electronic component including a semiconductor element as an electronic member will be described.

(Process 1: Mounting process)
FIG. 14 is a cross-sectional view showing a method for manufacturing a circuit board device (semiconductor device) according to the first embodiment and the second embodiment, and FIG. 15 is a circuit board device according to the first embodiment and the second embodiment. It is a top view which shows the manufacturing method of (semiconductor device). In the mounting process, first, as shown in FIGS. 14A and 15A, the electronic component 3 is mounted (mounted) on the deformable circuit board 4. As a result, a circuit board device 10 (unsealed) in which electronic parts including semiconductor elements are mounted on the main surface of the deformable circuit board is obtained.

(Step 2: First sealing step)
In the first sealing step, as shown in FIGS. 14B and 15B, the electronic member (electronic component) 3 is sealed with the liquid resin composition (a) 5. At this time, the circuit board 4 may be sealed. The electronic member 3 and the circuit board 4 can be sealed by, for example, a printing method, a dispensing method, a dipping method, or the like. Specifically, for example, the liquid resin composition (a) 5 is printed on the mounting surface of the circuit board 4, or the circuit board 4 is immersed in the liquid resin composition (a) 5 and dried. Can be sealed. Among these, the method that can be used in the roll-to-roll process is preferable because the manufacturing process can be shortened. In the first sealing step, as shown in FIG. 6, the liquid resin composition (a) 5 may be sealed so as to cover the bottom part (pin part on the circuit board 4 side) and the side surface of the electronic component 3. 7, the liquid resin composition (a) 5 may be sealed so as to cover the entire surface of the electronic component 3.

  When the electronic member 3 is mounted on both main surfaces of the circuit board 4, the electronic member 3 mounted on both main surfaces of the circuit board 4 is sealed as shown in FIGS. 6 and 7. It's okay. In the first sealing step, as shown in FIG. 15 (b), the resin composition (a) 5 may be provided only on at least a part of the circuit board 4, and the resin composition is entirely formed on the main surface of the circuit board 4. Object (a) 5 may be provided. For example, the resin composition (a) 5 may be provided only on the electronic member to be sealed and its peripheral portion. When the circuit board 4 has wiring, the wiring may be sealed with the resin composition (a) 5. In addition, when the circuit board 4 has only wiring as an electronic member, wiring is sealed with a liquid resin composition at a 1st process.

(Step 3: First curing step)
In the first curing step, as shown in FIGS. 14C and 15C, the electronic member 3 is sealed with the liquid resin composition (a) 5 in the first sealing step, and then the liquid state. The resin composition (a) 5 is cured. Thereby, the resin substrate (a) 1 is formed, and the circuit board device 50 in which the electronic member 3 is sealed with the resin substrate (a) 1 is obtained. As the curing, for example, heat curing by heating or photocuring by exposure can be performed.

(Step 4: Second sealing step)
In the second sealing step, as shown in FIGS. 14 (d) and 15 (d), a film-like resin having elasticity after curing the electronic member 3 sealed with the cured resin (a) 1. Seal with composition (b) 6. Specifically, a film-shaped resin composition (b) is attached to the main surface of the circuit board 4 on which the cured resin (a) 1 is formed, and the electronic member 3 together with the cured resin (a) 1. Coating. Sealing can be performed by a roll laminator, a vacuum laminator or the like. Among these, a method that can be used in the Roll to Roll process (for example, a method that uses a roll laminator) is preferable because the manufacturing process can be shortened. In the present embodiment, an electronic component and / or a wiring may be provided between the cured resin (a) 1 and the film-like resin composition (b) 6. Moreover, in this embodiment, as shown in FIG.14 (d) and FIG.15 (d), you may provide the film-form resin composition (b) 6 so that the whole main surface of the circuit board 4 may be covered, and a circuit The film-like resin composition (b) 6 may be provided only on at least a part of the main surface of the substrate 4.

(Step 5: Second curing step)
In the second curing step, as shown in FIGS. 14 (e) and 15 (e), the film-like resin composition (b) 6 is cured. Thereby, the resin cured product (b) 2 is formed, and the circuit board device 100 is obtained.

(Process 5: Cutting process)
FIG. 16 is a cross-sectional view showing a cutting step in the method of manufacturing a circuit board device according to this embodiment. In the cutting step, as shown in FIG. 16, the circuit board is cut and separated to obtain a plurality of circuit board devices 200 having electronic members (for example, circuit components). As a result, a plurality of circuit board devices can be manufactured at a large area at a time, and the manufacturing process can be easily reduced.

  Although the circuit board device and the method for manufacturing the circuit board device according to the first embodiment and the second embodiment have been described above, the invention is not limited to the above aspect.

  For example, instead of the film-like resin composition (b) 6, a liquid resin composition (c) having elasticity after curing may be used. The liquid resin composition (c) may be, for example, a resin composition that can be used as the above-mentioned liquid resin composition (a), and the film-like resin composition (b) 6 is replaced with a suitable organic resin. It may be diluted with a solvent to form a resin varnish. The organic solvent used here is the same as the organic solvent described above.

  The following examples of the present invention will be described more specifically, but the present invention is not limited to these examples.

<Preparation of resin composition>
[Preparation of liquid resin composition (a) LB1 having elasticity after curing]
As component (A), 30 parts by mass of a hydrogenated styrene isoprene copolymer (trade name “Septon 2002” manufactured by Kuraray Co., Ltd.), and as component (B), isodecyl acrylate (manufactured by Arkema Co., Ltd., product name “ SR395 ") 30 parts by mass, (C) component 4-tert-butylcyclohexanol acrylate (manufactured by Arkema Co., Ltd., trade name" SR217 ") 37 parts by mass, (D) component tricyclodecane dimethanol diacrylate ( Shin-Nakamura Chemical Co., Ltd., trade name “NK Ester A-DCP”) 2 parts by mass, as component (E), bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (manufactured by BASF, trade name) "Irgacure 819") 1 part by weight is added to a 500 ml flask and mixed by stirring at a constant temperature (60 ° C). It was obtained Narubutsu (a) LB1.

[Preparation of resin varnish VA1]
As component (A ′), hydrogenated styrene butadiene rubber (manufactured by JSR Corporation, trade name “Dynalon 2324P”, weight average molecular weight: 1.0 × 10 ⁵ ), 80 parts by mass, and as component (F), nonanediol di 20 parts by mass of acrylate (manufactured by Hitachi Chemical Co., Ltd., trade name “Fancryl FA-129AS”), (E ′) component, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (manufactured by BASF Name “Irgacure 819”) 1.5 parts by mass and 125 parts by mass of toluene as a solvent were mixed with stirring to obtain a resin varnish VA1.

[Production of Film Resin Composition (b) FA1]
Surface release-treated PET film (manufactured by Teijin DuPont Films, trade name “Purex A31”, thickness: 25 μm) is used as a base film, and a knife coater (Yasui Seiki Co., Ltd.) is formed on the release-treated surface. The resin varnish VA1 was applied using a product name “SNC-350”). Next, after drying for 20 minutes at 100 ° C. in a dryer (trade name “MSO-80TPS”, manufactured by Futaba Kagaku Co., Ltd.), the surface release treatment PET film is placed on the resin side as a protective film. The film-shaped resin composition (b) FA1 was obtained. The thickness of the film-like resin composition (b) FA1 can be arbitrarily adjusted by adjusting the gap of the coating machine, but in this example, the thickness after curing is adjusted to 100 μm. did.

  In the same manner as in the above method, liquid resin compositions (a) LB2 to LB14 were obtained according to the blending ratios shown in Tables 1 to 3. In Tables 1 to 3, “Kayaflex BPAM-155” is not (A) a styrene elastomer, but is described as a component (A) for convenience.

<Evaluation of cured resin>
[Preparation of cured film for physical property evaluation]
Surface release treatment PET film (trade name “Purex A31”, manufactured by Teijin DuPont Films Co., Ltd., thickness: 25 μm) is used, and knife coater (manufactured by Yasui Seiki Co., Ltd., product name) on this release treatment surface. The liquid resin compositions (a) LB1 to LB14 were applied using “SNC-350”). Thereafter, these samples were irradiated with ultraviolet rays (wavelength: 365 nm) at an exposure amount of 2000 mJ / cm ^{2 using} an ultraviolet exposure machine (trade name “ML-320FSAT” manufactured by Mikasa Co., Ltd.). A cured film for evaluating physical properties (film made of cured resin (a)) was obtained. At this time, the thickness of the cured film can be arbitrarily adjusted by adjusting the gap of the coating machine, but in this example, the thickness after curing was adjusted to 100 μm.

Further, ultraviolet rays (wavelength: 365 nm) were applied to the film-shaped resin composition (b) FA1 (thickness: 100 μm) with an ultraviolet exposure machine (trade name “ML-320FSAT” manufactured by Mikasa Co., Ltd.) at 2000 mJ / Irradiation was performed with an exposure amount of cm ² to obtain a cured film for evaluating the physical properties of FA1 (film made of a cured resin (b)).

[Preparation of film for physical property evaluation]
HT-6240 (trade name, film-like silicone resin, thickness: 100 μm) and TPU (manufactured by Flextronics, thermoplastic polyurethane film, thickness: 100 μm) were prepared as films for evaluating physical properties.

[Evaluation of elastic modulus and elongation]
The cured film for evaluating physical properties and the film for evaluating physical properties obtained above were cut into strips having a length of 40 mm and a width of 10 mm to prepare measurement samples. The elastic modulus and elongation of the measurement sample were measured under an environment of 25 ° C. using an autograph (manufactured by Shimadzu Corporation, trade name “EZ-S”), and a stress-strain curve was measured. The elastic modulus and elongation of the cured film were determined from (stress-strain curve). The distance between chucks at the time of measurement was 20 mm, and the pulling speed was 50 mm / min. In addition, the elasticity modulus measured here the value in the load of 0.5 to 1.0N, and the elongation rate measured the value at the time of a film fracture | rupture (breaking elongation rate). The results are shown in Tables 1-4.

[Evaluation of stretch recovery rate]
The cured film for evaluating physical properties and the film for evaluating physical properties obtained above were cut into strips having a length of 70 mm and a width of 5 mm to prepare measurement samples. The expansion / contraction recovery rate of the measurement sample was measured using a microforce tester (manufactured by Illinois Tool Works Inc., trade name “Instron 5948”) in an environment of 25 ° C. Here, the expansion / contraction recovery rate is the difference between X when the displacement amount (strain) applied in the first tensile test is X, and then when the tensile test is performed again after returning to the initial position and when the load starts to be applied. Is Y, and refers to R calculated by the formula: R (%) = Y / X × 100. In this measurement, the initial length (distance between chucks) was 50 mm, and X was 25 mm (strain 50%). The results are shown in Tables 1-4.

[Evaluation of total light transmittance, YI, haze]
The cured film for evaluating physical properties and the film for evaluating physical properties obtained above were cut into strips having a length of 30 mm and a width of 30 mm to prepare measurement samples. The total light transmittance, YI (Yellowness Index) and haze of this measurement sample were measured using a spectroscopic haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., trade name “SH7000”) under an environment of 25 ° C. The results are shown in Tables 1-4.

[Evaluation of adhesion]
Liquid resin composition using a knife coater (trade name “SNC-350”, manufactured by Yasui Seiki Co., Ltd.) on a polyimide film (trade name “Kapton 100H”, manufactured by Toray DuPont Co., Ltd.) having a thickness of 50 μm. (A) LB1 to LB14 were applied so that the film thickness after curing was 100 μm. In addition, a vacuum laminator (Nikko Materials Co., Ltd., trade name “V130”) was used on a polyimide film having a thickness of 50 μm (trade name “Kapton 100H” manufactured by Toray DuPont Co., Ltd.) under the following conditions. The film-like resin composition (b) FA1 (thickness: 100 μm) was attached. Thereafter, ultraviolet rays (wavelength: 365 nm) were irradiated with an exposure amount of 2000 mJ / cm ^{2 using} an ultraviolet exposure machine (trade name “ML-320FSAT” manufactured by Mikasa Co., Ltd.). Thereafter, the obtained cured film was cut into a strip shape having a length of 50 mm and a width of 10 mm to obtain samples for evaluating adhesion of LB1 to LB14 and FA1.
・ Heater temperature: upper 90 ℃, lower 40 ℃
・ Time: 60s
・ Pressure: 0.5 MPa

In addition, a vacuum laminator (Nikko Materials Co., Ltd., trade name “V130”) was used on a polyimide film having a thickness of 50 μm (trade name “Kapton 100H” manufactured by Toray DuPont Co., Ltd.) under the following conditions. And HT-6240 (trade name, film-like silicone resin, thickness: 100 μm) and TPU (manufactured by Flextronics, thermoplastic polyurethane film, thickness: 100 μm) were attached. Thereafter, the obtained film was cut into a strip shape having a length of 50 mm and a width of 10 mm to obtain a sample for evaluating adhesion of HT-6240 and TPU.
・ Heater temperature: Upper 100 ℃, Lower 100 ℃
・ Time: 60s
・ Pressure: 0.5 MPa

  The cured film side of the obtained adhesion evaluation sample was fixed to a copper plate using an adhesive (trade name “Cemedine Super X Gold” manufactured by Cemedine Co., Ltd.), and an autograph (( Using Shimadzu Corporation, trade name “EZ-S”), the polyimide film was peeled from the cured film fixed to the copper plate, and the adhesion strength was evaluated by measuring the adhesion strength. The polyimide film was peeled off by peeling off the polyimide film at a speed of 50 mm / min so that the cured film and the peeled polyimide film formed an angle of 90 degrees. The results are shown in Tables 1-4.

[Evaluation of moisture permeability]
The cured film for physical property evaluation and the film for physical property evaluation obtained above were evaluated in an environment of 40 ° C./90% according to the moisture permeation cup method (JIS Z0208), and the moisture permeability was determined. A sample having a moisture permeability of 100 g / m ² · 24 h or less was designated as A, and a sample having a moisture permeability of 100 g / m ² · 24 h or more was designated as B. The results are shown in Tables 1-4.

1) Hydrogenated styrene isoprene copolymer (trade name “Septon 2002” manufactured by Kuraray Co., Ltd.), weight average molecular weight: 55,000
2) Hydrogenated styrene-butadiene copolymer (Clayton Polymer Japan Co., Ltd., trade name “Clayton MD6951”), weight average molecular weight: 60,000
3) Rubber-modified polyamide (manufactured by Nippon Kayaku Co., Ltd., trade name “Kayaflex BPAM-155”), weight average molecular weight: 31,000
4) Isodecyl acrylate (trade name “Sartomer SR395” manufactured by Arkema Co., Ltd.)
5) Isooctyl acrylate (manufactured by Arkema Co., Ltd., trade name “Sartomer SR440”)
6) Lauryl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name “LA”)
7) 4-tert-butylcyclohexanol acrylate (manufactured by Arkema Co., Ltd., trade name “Sartomer SR217”)
8) 3,3,5-trimethylcyclohexanol acrylate (manufactured by Arkema Co., Ltd., trade name “Sartomer SR420”)
9) Tricyclodecyl acrylate (manufactured by Hitachi Chemical Co., Ltd., trade name “Fancryl FA-513AS”)
10) Cyclohexyl acrylate (manufactured by NOF Corporation, trade name “Blemmer CHA”)
11) Tricyclodecane dimethanol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “NK Ester A-DCP”)
12) Cyclohexanedimethanol diacrylate (trade name “Sartomer CD406” manufactured by Arkema Co., Ltd.)
13) Nonanediol diacrylate (manufactured by Hitachi Chemical Co., Ltd., trade name “Fancryl FA-129AS”)
14) Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (manufactured by BASF Japan Ltd., trade name “Irgacure 819”)

  As shown in Tables 1 to 3, LB1 to LB10 are excellent in stretchability (elongation rate and stretch recovery rate) and adhesion as a cured resin obtained by photoradical polymerization. In LB12 which is a composition which does not contain (B) component, and LB13 which is a composition which contains (D) component excessively, an elasticity modulus rose and elongation rate and expansion-contraction recovery property fell significantly. Moreover, LB14 is a composition which does not contain (A) component, and elongation rate and expansion-contraction recovery property fell significantly.

Example 1
[Fabrication of Semiconductor Device A]
A SOP having a thickness of 1.2 mm and a size of 10 mm × 10 mm was mounted on a copper-plated polyimide substrate to obtain a semiconductor device A. The elastic modulus of the polyimide substrate at 25 ° C. was 9.1 GPa.

[Fabrication of Semiconductor Device B]
A semiconductor device B was obtained by mounting a silicon chip having a thickness of 0.1 mm and a size of 10 mm × 10 mm on a copper-plated polyimide substrate. The elastic modulus of the polyimide substrate at 25 ° C. was 9.1 GPa.

[Fabrication of circuit board C]
Metal foil (product name, Kapton EN: 25 μm, plated copper: 7.5 μm, “METAL ROYAL” is a registered trademark) is etched on the metal foil and comb pattern (no gold plating) , Line 35 μm, space 35 μm, number of leads: minus side 35, plus side 34), and circuit board C was obtained. The elastic modulus of the circuit board C at 25 ° C. was 5.3 GPa.
[Fabrication of circuit board D]
Etching copper foil on 86mm long x 15mm wide Meta Royal (Toray Film Processing Co., Ltd., trade name, Kapton EN: 25 μm, plated copper: 7.5 μm, “Meta Royal” is a registered trademark) Patterns (length 12 mm x width 15 mm, no gold plating, wiring width 100 μm, repeat meander 5 times, meander length 2 mm, meander diameter 1 mm, angle 45 ° C.) in three vertical locations (from the vertical end) 19 mm position, 37 mm position to 49 mm position, and 59 mm position to 71 mm position), and the circuit board D shown in FIG. 19 is obtained by cutting the Kapton part by laser processing so that the Kapton width is 250 μm centering on the wiring. It was. In FIG. 19, reference numeral 12 indicates a copper wiring, and reference numeral 13 indicates a kapton. The elastic modulus of the circuit board D at 25 ° C. was 5.3 GPa.

[Fabrication of semiconductor device for appearance evaluation]
After applying the liquid resin composition (a) LB1 to the mounting surface of the semiconductor device A by the dispensing method and sealing the SOP, with an ultraviolet exposure machine (trade name “ML-320FSAT” manufactured by Mikasa Co., Ltd.) Ultraviolet rays (wavelength: 365 nm) were irradiated at an exposure amount of 2000 mJ / cm ² . Thereby, a semiconductor device for appearance evaluation was obtained.

[Fabrication of semiconductor device for peeling / cracking evaluation]
Except for using the semiconductor device B instead of the semiconductor device A, a semiconductor device for peeling / cracking evaluation was obtained in the same manner as the production of the semiconductor device for appearance evaluation.

[Production of circuit board for connection reliability evaluation]
A semiconductor device for connection reliability evaluation was obtained in the same manner as the production of the semiconductor device for appearance evaluation, except that the circuit board C was used instead of the semiconductor device A.

[Production of circuit board for stretch recovery rate evaluation]
Except that the circuit board D was used in place of the semiconductor device A, a semiconductor device for stretch recovery rate evaluation was obtained in the same manner as the fabrication of the semiconductor device for appearance evaluation.

(Example 2)
Except for using LB2 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

(Example 3)
Except for using LB3 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and an expansion / contraction recovery rate evaluation A circuit board was obtained.

Example 4
Except for using LB4 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

(Example 5)
Except for using LB5 instead of LB1, in the same manner as in Example 1, a semiconductor device for external appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and an expansion / contraction recovery rate evaluation A circuit board was obtained.

(Example 6)
Except for using LB6 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

(Example 7)
Except for using LB7 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and an expansion / contraction recovery rate evaluation A circuit board was obtained.

(Example 8)
Except for using LB8 in place of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

Example 9
Except for using LB9 in place of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

(Example 10)
Except for using LB10 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

(Example 11)
[Fabrication of semiconductor device for appearance evaluation]
Using a vacuum laminator (trade name “V130” manufactured by Nikko Materials Co., Ltd.), a film-like resin composition (on the mounting surface of the semiconductor device for appearance evaluation obtained in Example 1 under the following conditions ( b) FA1 was laminated.
・ Heater temperature: upper 90 ℃, lower 40 ℃
・ Time: 60s
・ Pressure: 0.5 MPa

Next, ultraviolet rays (wavelength: 365 nm) are irradiated with an exposure amount of 2000 mJ / cm ² with an ultraviolet exposure machine (trade name: “ML-320FSAT”, manufactured by Mikasa Co., Ltd.), and FA1 is photocured, whereby the external appearance is obtained. A semiconductor device for evaluation was obtained.

[Fabrication of semiconductor device for peeling / cracking evaluation]
Except for using the semiconductor device for peeling / cracking evaluation obtained in Example 1, a semiconductor device for peeling / cracking evaluation was obtained in the same manner as in the production of the semiconductor device for appearance evaluation.

[Production of circuit board for connection reliability evaluation]
A circuit board for connection reliability evaluation was obtained in the same manner as in the production of the semiconductor device for appearance evaluation except that the circuit board for connection reliability evaluation obtained in Example 1 was used.

[Production of circuit board for stretch recovery rate evaluation]
Except for using the circuit board D obtained in Example 1, a circuit board for stretch recovery rate evaluation was obtained in the same manner as the fabrication of the semiconductor device for appearance evaluation.

(Example 12)
[Fabrication of semiconductor device for appearance evaluation]
After dipping the semiconductor device A into the liquid resin composition (a) LB1, the semiconductor device A was placed on a wire mesh, and unnecessary LB1 was dropped. Next, ultraviolet rays (wavelength: 365 nm) were irradiated at an exposure amount of 2000 mJ / cm ^{2 using} an ultraviolet exposure machine (trade name “ML-320FSAT” manufactured by Mikasa Corporation). Thereby, a semiconductor device for appearance evaluation was obtained.

[Fabrication of semiconductor device for peeling / cracking evaluation]
Except that the semiconductor device B was used in place of the semiconductor device A, a semiconductor device for peeling / cracking evaluation was obtained in the same manner as in the production of the semiconductor device for appearance evaluation.

[Fabrication of semiconductor device for connection reliability evaluation]
A circuit board for connection reliability evaluation was obtained in the same manner as the fabrication of the semiconductor device for appearance evaluation, except that the circuit board C was used instead of the semiconductor device A.

[Production of circuit board for stretch recovery rate evaluation]
A circuit board for expansion / contraction recovery rate evaluation was obtained in the same manner as in the production of the semiconductor device for appearance evaluation, except that the circuit board D was used instead of the semiconductor device A.

(Example 13)
[Fabrication of semiconductor device for appearance evaluation]
A semiconductor device for appearance evaluation was obtained in the same manner as in Example 11 except that the semiconductor device for appearance evaluation obtained in Example 12 was used.

[Fabrication of semiconductor device for peeling / cracking evaluation]
A semiconductor device for peeling / cracking evaluation was obtained in the same manner as in Example 11 except that the semiconductor device for peeling / cracking evaluation obtained in Example 12 was used.

[Production of circuit board for connection reliability evaluation]
A circuit board for connection reliability evaluation was obtained in the same manner as in Example 11 except that the circuit board for evaluation of connection reliability obtained in Example 12 was used.

[Production of circuit board for stretch recovery rate evaluation]
A circuit board for stretch recovery rate evaluation was obtained in the same manner as in Example 11 except that the circuit board for stretch recovery rate evaluation obtained in Example 12 was used.

(Example 14)
Except for using LB2 instead of LB1, in the same manner as in Example 11, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

(Example 15)
Except for using LB11 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and an expansion / contraction recovery rate evaluation A circuit board was obtained.

(Comparative Example 1)
In Comparative Example 1, a semiconductor device B was prepared as a sample for peeling / cracking evaluation, and a circuit board C was prepared as a sample for evaluating connection reliability. A circuit board D was prepared as a sample for evaluating the recovery rate of the circuit board. In Comparative Example 1, no appearance evaluation was performed.

(Comparative Example 2)
In Comparative Example 2, the step caused by the electronic component was not relaxed with the liquid resin composition (a). Specifically, using a vacuum laminator (product name “V130”, manufactured by Nikko Materials Co., Ltd.), a film-like surface is mounted on the mounting surfaces of the semiconductor devices A and B and the circuit boards C and D under the following conditions. Resin composition (b) FA1 is laminated, and then irradiated with ultraviolet light (wavelength: 365 nm) at an exposure amount of 2000 mJ / cm ^{2 using} an ultraviolet exposure machine (trade name “ML-320FSAT” manufactured by Mikasa Co., Ltd.). A semiconductor device for external appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a circuit board for expansion / contraction recovery rate evaluation were obtained.
・ Heater temperature: upper 90 ℃, lower 40 ℃
・ Time: 60s
・ Pressure: 0.5 MPa

(Comparative Example 3)
[Fabrication of semiconductor device for appearance evaluation]
A liquid resin composition (a) LB1 is applied to the mounting surface of the semiconductor device A by a dispensing method and the SOP is sealed. Then, the LB1 is not cured, and a vacuum laminator (Nikko Materials Corporation, trade name) “V130”) was used to laminate the film-like resin composition (b) FA1 on the mounting surface of the semiconductor device A under the following conditions.
・ Heater temperature: upper 90 ℃, lower 40 ℃
・ Time: 60s
・ Pressure: 0.5 MPa

Next, ultraviolet rays (wavelength: 365 nm) were irradiated at an exposure amount of 2000 mJ / cm ^{2 using} an ultraviolet exposure machine (trade name “ML-320FSAT” manufactured by Mikasa Corporation). Thereby, a semiconductor device for appearance evaluation was obtained.

[Fabrication of semiconductor device for peeling / cracking evaluation]
Except that the semiconductor device B was used in place of the semiconductor device A, a semiconductor device for peeling / cracking evaluation was obtained in the same manner as in the production of the semiconductor device for appearance evaluation.

[Production of circuit board for connection reliability evaluation]
A circuit board for connection reliability evaluation was obtained in the same manner as the fabrication of the semiconductor device for appearance evaluation, except that the circuit board C was used instead of the semiconductor device A.

[Production of circuit board for stretch recovery rate evaluation]
A circuit board for expansion / contraction recovery rate evaluation was obtained in the same manner as in the production of the semiconductor device for appearance evaluation, except that the circuit board D was used instead of the semiconductor device A.

(Comparative Example 4)
The film-shaped resin composition (b) HT-6240 (trade name, film-shaped silicon resin, thickness: 100 μm) was used in place of FA1, and a vacuum laminator (Nikko Materials Co., Ltd.). Manufactured under the trade name “V130”), the semiconductor device for external appearance evaluation was performed in the same manner as in Comparative Example 2 except that the heater temperature was 100 ° C. in the upper part, 100 ° C. in the lower part, and no ultraviolet irradiation was performed. Then, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a circuit board for stretch recovery rate evaluation were obtained.

(Comparative Example 5)
In place of the film-like resin composition (b) FA1, the use of TPU (manufactured by Flextronics, thermoplastic polyurethane film, thickness: 100 μm), vacuum laminator (manufactured by Nikko Materials Co., Ltd., trade name “ V130 ") heater temperature was 100 ° C in the upper part and 100 ° C in the lower part, and the semiconductor device for appearance evaluation, peeling / cracking evaluation was performed in the same manner as in Comparative Example 2 except that the ultraviolet irradiation was not performed. A semiconductor device, a circuit board for connection reliability evaluation, and a circuit board for expansion / contraction recovery rate evaluation were obtained.

(Comparative Example 6)
Except for using LB12 in place of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

(Comparative Example 7)
Except for using LB13 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and an expansion / contraction recovery rate evaluation A circuit board was obtained.

(Comparative Example 8)
Except for using LB14 instead of LB1, in the same manner as in Example 1, a semiconductor device for appearance evaluation, a semiconductor device for peeling / cracking evaluation, a circuit board for connection reliability evaluation, and a stretch recovery rate evaluation A circuit board was obtained.

<Mounting evaluation>
About Examples 1-15 and Comparative Examples 1-8, external appearance evaluation, peeling / cracking evaluation, connection reliability evaluation, and circuit board recovery rate evaluation were performed.

(Evaluation of step following ability: Appearance evaluation)
The semiconductor device for appearance evaluation was visually observed to evaluate the step following ability. The case where bubbles were not included was designated as “A”, and the case where bubbles were contained, or the case where there were other defects was designated as “B”. The results are shown in Tables 5-8.

(Winding test: peeling / cracking evaluation)
A semiconductor device for peeling / cracking evaluation was wound around a tube having a diameter of 22 mm, thereby applying stress by bending and pulling to the semiconductor device. Thereafter, the semiconductor device was visually observed to evaluate the presence or absence of peeling and cracking of the silicon chip. The case where there was no change was designated as “A”, and the case where peeling or cracking of the silicon chip occurred was designated as “B”. The results are shown in Tables 5-8.

(Measurement of HAST resistance: connection reliability evaluation)
A circuit board for connection reliability evaluation was placed in an accelerated life test apparatus (trade name “PL-422R8” manufactured by HIRAYAMA), and the insulation resistance was measured under the conditions of 130 ° C., 85%, 100 hours. In the evaluation of connection reliability, over 100 hours, the case where the insulation resistance exceeded 10 ⁶ Ω was “A”, and the case where the insulation resistance was less than 10 ⁶ Ω was “B”. The results are shown in Tables 5-8.

(20% tensile test: Evaluation of expansion / contraction recovery rate of circuit board)
The expansion / contraction recovery rate of the circuit board for evaluating the expansion / contraction recovery rate was measured in a 25 ° C. environment using a microforce tester (product name “Instron 5948” manufactured by Illinois Tool Works Inc.). Here, the expansion / contraction recovery rate is the difference between X when the displacement amount (strain) applied in the first tensile test is X, and then when the tensile test is performed again after returning to the initial position and when the load starts to be applied. Represents Y calculated by the formula: R (%) = Y / X × 100. In this measurement, the initial length (distance between chucks) was 56 mm (between the 15 mm portions of the circuit board D), and X was 11.2 mm (strain 20%). The case where R exceeds 80 was designated as “A”, and the case where R was less than 80 was designated as “B”. The results are shown in Tables 5-8.

＊未硬化

* Uncured

In Comparative Example 1, there was a crack of the silicon chip in the peeling / cracking evaluation. In connection reliability evaluation, the resistance began to decrease in less than 1 hour, and the insulation resistance was less than 10 ⁶ Ω. In the evaluation of the recovery rate of the circuit board, it did not return to its original state. In Comparative Example 2, when the vacuum lamination was performed, the pin portion of the SOP could not be sufficiently embedded, and a gap was generated between the pin portion and the resin composition. In Comparative Example 3, since the liquid resin composition (a) was not cured and remained in a liquid state, the vacuum laminate could not be evacuated and a film-like resin composition (b) could not be formed. In Comparative Example 4, although vacuum lamination was performed, adhesion of the resin composition to the substrate was weak, and all evaluations were B. Although the comparative example 5 was able to affix the resin composition on a board | substrate by vacuum lamination, the level | step difference embedding property was bad and the external appearance evaluation was B. The peeling / cracking evaluation was A, but the connection reliability evaluation was B. In the evaluation of the recovery rate of the circuit board, it was peeled off from the circuit board when extended by 20%, and the evaluation was B. In Comparative Examples 6 and 7, appearance evaluation and connection reliability were A, but peeling / cracking evaluation and circuit board recovery rate evaluation were B. In Comparative Example 8, the appearance evaluation was A, but the peel / crack evaluation, connection reliability, and circuit board recovery rate evaluation were B.

DESCRIPTION OF SYMBOLS 1 ... Hardened | cured material of liquid resin composition (a), 2 ... Hardened | cured material of film-like resin composition (b), 3 ... Electronic member, 4 ... Circuit board, 5 ... Liquid resin composition (a), 6 ... Film-like resin composition (b), 10 ... Circuit board device (unsealed), 50, 100, 200 ... Circuit board device (after sealing).

Claims (14)

A deformable circuit board;
An electronic member provided on at least one main surface of the circuit board;
A cured product of a liquid resin composition (a) that seals at least a part of the electronic member,
The circuit board device, wherein the stretch recovery rate of the cured product of the resin composition (a) is 80% or more.   The circuit board device according to claim 1, wherein the circuit board has a tensile elastic modulus at 25 ° C. of 3 MPa or more.   The circuit board device according to claim 1, wherein a tensile elastic modulus at 25 ° C. of the circuit board is less than 3 MPa.   The circuit board device according to claim 1, wherein the resin composition (a) is photocurable.   The circuit board device according to claim 1, wherein the circuit board has a deformable wiring on at least one main surface. The resin composition (a) is (A) a styrenic elastomer,
(B) a monofunctional (meth) acrylate having an alkyl chain;
(C) a monofunctional (meth) acrylate having an alicyclic skeleton;
(D) a bifunctional or higher functional compound having two or more ethylenically unsaturated groups;
(E) The circuit board apparatus as described in any one of Claims 1-5 containing a polymerization initiator.   The circuit board device according to claim 6, wherein the component (A) is a hydrogenated styrene elastomer.   The circuit board device according to claim 6 or 7, wherein the component (E) is a radical photopolymerization initiator.   The circuit board device according to any one of claims 6 to 8, wherein the alkyl chain in the component (B) has 12 or less carbon atoms.   Content of the said (D) component is 0.3-20 mass% with respect to the total amount of the said (A) component, the said (B) component, the said (C) component, and the said (D) component. Item 10. The circuit board device according to any one of Items 6 to 9.   The film-like resin composition (b) having stretchability after curing, provided to cover the electronic member on the main surface of the circuit board on which the cured product of the resin composition (a) is formed. The circuit board device according to any one of claims 1 to 10, further comprising a cured product. The resin composition (b)
(A ′) a styrenic elastomer,
(F) a polymerizable compound;
The circuit board device according to claim 11, comprising (E ′) a polymerization initiator.   The circuit board device according to claim 12, wherein the component (E ′) is a radical photopolymerization initiator. The content of the component (A ′) is 50 to 90% by mass with respect to the total amount of the component (A ′) and the component (F),
Content of the said (F) component is 10-50 mass% with respect to the total amount of the said (A ') component and the said (F) component,
The content of the (E ') component is 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of the (A') component and the (F) component, according to claim 12 or 13. Circuit board device.

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