JPH10231354A - Epoxy resin composition, thermosetting resin film and method for forming cured resin film on substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid epoxy resin composition having photosetting and thermosetting properties and excellent storage stability, a thermosetting resin film and a process for forming a cured resin film on a substrate. SOLUTION: This epoxy resin composition is composed of (i) a liquid epoxy resin, (ii) a latent curing agent having an activation temperature of >=80 deg.C and (iii) a photopolymerizable compound having >=4 (meth)acryloyl groups in one molecule. This thermosetting film is composed of a solid polymer of a polymerizable compound having >=4 (meth)acryloyl groups in one molecule, a liquid epoxy resin contained in the solid polymer and a latent curing agent having an activation temperature of >=80 deg.C and contained in the solid polymer. The formation of a cured resin film on a substrate is carried out by forming a coating layer composed of the above composition on a substrate, irradiating the coating layer with actinic light to form a thermosetting resin film layer and heating the obtained thermosetting resin film to form a cured resin film layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid epoxy resin composition, a thermosetting film, and a method for forming a cured resin film on a substrate.

[0002]

2. Description of the Related Art Liquid epoxy resin compositions having both photocurability and thermosetting properties have been known. As such an epoxy resin composition, for example, JP-A-7-2
No. 28669 can be shown. This composition comprises a liquid epoxy resin and 4,4′-diaminodiphenyl sulfone or 9,9′-bis (3-chloro-4
An aromatic diamine compound having two aminophenyl groups such as -aminophenyl) fluorene and 2-hydroxy-
It comprises a compound having a (meth) acrylate group such as 3-phenoxypropyl acrylate or dicyclopentanyl methacrylate, and a radical generator. This liquid composition can be made into a solid film by irradiating the liquid film with ultraviolet rays, and then, by heating this solid film, it can be made into a cured film. However, the composition is still unsatisfactory in storage stability, and has a problem that gelation occurs when left at room temperature for a long time.

[0003]

SUMMARY OF THE INVENTION The present invention provides a liquid epoxy resin composition, a thermosetting resin film, and a method for forming a cured resin film on a substrate, which have both photocurability and thermosetting properties and excellent storage stability. Is to provide

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, according to the present invention, (i) a liquid epoxy resin, (ii) a latent curing agent having an activation temperature of 80 ° C. or higher, and (ii)
i) An epoxy resin composition comprising a photopolymerizable compound having four or more (meth) acryloyl groups in a molecule is provided. Further, according to the present invention, a solid polymer of a polymerizable compound having four or more (meth) acryloyl groups in a molecule, a liquid epoxy resin contained in the solid polymer, and a solid polymer There is provided a thermosetting film comprising a latent curing agent having an activation temperature of 80 ° C. or higher contained in the coalescence. Further, according to the present invention, a step of forming a coating layer comprising the composition on a substrate, a step of irradiating the coating layer with actinic rays to form a thermosetting resin film layer, A method for forming a cured resin film on a substrate is provided, comprising a step of forming a cured resin film layer by heating the resin film layer.

[0005]

DETAILED DESCRIPTION OF THE INVENTION The composition of the present invention contains a liquid epoxy resin. The liquid epoxy resin is a liquid epoxy resin that is liquid at room temperature or working temperature, and various types of conventionally known liquid epoxy resins are used. As such an epoxy resin, for example, bisphenol A-based epoxy resin,
Bisphenol AD epoxy resin, Bisphenol F
Epoxy resin, phenol borak epoxy resin,
Examples include hydrogenated bisphenol A-based epoxy resins, cycloaliphatic epoxy resins, and glycidyl ethers of organic carboxylic acids. In the present invention, one or more of these can be used. In addition, as long as the composition maintains a liquid state, an appropriate amount of a solid epoxy resin can be added at room temperature.

[0006] The composition of the present invention contains a latent curing agent. As the latent curing agent used in the present invention, various types of conventionally known curing agents can be used. In particular, those having an activation temperature of 80 ° C. or higher, preferably 90 ° C. or higher are advantageously used. Such curing agents include dicyandiamide-based curing agents, urea-based curing agents, organic acid hydrazide-based curing agents, polyamine salt-based curing agents, and amine adduct-based curing agents. The upper limit of the activation temperature is not particularly limited, but is preferably 150 ° C. or lower, and more preferably 140 ° C. or lower, from the viewpoint of obtaining a high curing rate. The amount of the curing agent
An appropriate amount is selected depending on the specific type, but usually,
The number of equivalents of the functional group of the curing agent is 1 per equivalent of epoxy group.
The ratio is from 0.7 to 0.7 equivalent, preferably from 1 to 0.8 equivalent.

[0007] The composition of the present invention contains a compound having four or more (meth) acryloyl groups in the molecule. As such a (meth) acryloyl group-containing compound,
Conventionally known various ones are used. Examples of such a material include those represented by the following general formula (1).

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In the above formula, X represents hydrogen or a methyl group;
R represents a tetravalent or more organic group, and n represents a number of 4 or more.
The organic group R includes an aliphatic group and an aromatic group. Such a group R is derived from a hydroxyl group compound having four or more hydroxyl groups. Such a hydroxyl group compound includes a compound having an alcoholic hydroxyl group and a compound having a phenolic hydroxyl group. Examples of the alcoholic hydroxyl group-containing compounds include sugars such as tetritol (erythritol, threitol, etc.), pentitol (ribitol, arabinitol, xylitol, etc.), hexitol (allitol, galactitol, sorivitol, glucitol, mannitol, idiitol, etc.), heptitol and the like. Alcohol; pentaerythritol;
Polyerythritol such as dipentaerythritol and tripentaerythritol; polyglycerin such as diglycerin and triglycerin; degradation products of cellulose; polyvinyl alcohol; On the other hand, examples of the compound containing a phenolic hydroxyl group include, for example, four or more polyhydric phenol compounds and phenol resins. The hydroxyl group compound used in the present invention is soluble in an organic solvent or water-soluble.

The poly (meth) represented by the general formula (1)
The acrylate compound can be obtained by subjecting a hydroxyl group compound and (meth) acrylic acid or a lower alkyl ester thereof to an esterification reaction or an exchange esterification reaction according to a conventionally known method. In this case, the reaction is
In the presence of a catalyst, in the presence or absence of a solvent,
This is performed at a temperature of about 50 ° C. As the catalyst, sulfuric acid or a sulfonic acid type ion exchange resin is used.

The (meth) acrylate compound used in the present invention must be a compound having 4 or more, preferably 5 or more (meth) acryloyl groups, and having 3 or less (meth) acryloyl groups. Compounds have insufficient film-forming ability. The upper limit of the number of (meth) acryloyl groups is not particularly limited, but is usually 200 or less,
Preferably, the number is 100 or less. The compound having a (meth) acryloyl group referred to in the present specification means a compound having an acryloyl group, a compound having a methacryloyl group, a compound having an acryloyl group and a methacryloyl group, and a mixture of two or more thereof. Is what you do. The (meth) acryloyl group-containing compound exhibits organic solvent solubility or water solubility, and has a number average molecular weight of 1,000.
Or less, preferably 5000 or less, more preferably 200
0 or less. The compound is used in an amount of 5 to 100 parts by weight, preferably 10 to 30 parts by weight, more preferably 10 to 20 parts by weight, per 100 parts by weight of the liquid epoxy resin.

[0011] A radical generator may be included to promote the photopolymerization of the (meth) acryloyl group. From the viewpoint of storage stability of the composition, the radical generator is preferably added at the time of applying the composition or forming a film. Of course, it can be added during the production of the composition, but in this case,
The composition is stored in a UV-blocking container to prevent exposure to UV radiation. The radical generator is a compound that generates a radical upon irradiation with an actinic ray such as an ultraviolet ray or an electron beam, and various conventionally known ones are used. Examples of such a substance include 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzoin, acetophenone and the like. The ratio of the radical generator used is (meth) acryloyl group-containing compound 1
The amount is 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, per 100 parts by weight.

The composition of the present invention may contain, if necessary, other auxiliary components such as a thermosetting accelerator, a rheological additive,
Reactive diluent, surfactant, filler, conductive agent, colorant,
A flame retardant or the like can be added.

The composition of the present invention can be made into a liquid film, and a solid (including semi-solid) film can be formed by irradiating the liquid film with actinic rays such as ultraviolet rays and electron beams. This solid film is irradiated with actinic rays by radicals generated from a radical generator, thereby producing (meth)
The acryloyl group-containing compound is formed by polymerization (gelling). This solid film is
A solid polymer of a (meth) acryloyl group-containing compound,
The thermosetting film comprises a liquid epoxy resin contained in the solid polymer and a latent curing agent contained in the solid polymer. The thermosetting film obtained as described above can be made into a cured film by heating it to a temperature not lower than the activation temperature of the latent curing agent. This cured film is formed by a reaction between an epoxy resin and a latent curing agent. The heating temperature for curing the thermosetting film is usually from 80 to 240 ° C, preferably from 150 to 180 ° C.
° C.

The composition of the present invention can be used as a liquid or film adhesive. In order to form the composition of the present invention into a film adhesive, the composition is formed into a liquid film, which is irradiated with actinic rays. Thereby, the (meth) acryloyl group-containing compound is polymerized (gelled),
A thermosetting solid film is formed. Since this solid film contains an epoxy resin having curing reactivity, it has good adhesiveness. The film-like adhesive of the present invention can be applied to a substrate or an article (IC
An object to be bonded such as an electronic component such as a chip) is pressed and heated to obtain a cured film in which the object to be bonded is firmly adhered. Further, by interposing the thermosetting film between the two adherends and heating the thermosetting film under pressure, the two adherends can be firmly bonded via the cured film. When the composition of the present invention is used as a liquid adhesive, the composition is applied on an adherend such as a substrate, and irradiated with actinic rays to form a solid film,
Next, another adherend is pressed onto the film and heated. Thereby, the other adherend can be firmly adhered to the one adherent via the cured film. The thermosetting solid film of the present invention can be advantageously used as an adhesive film for die bonding. In order to bond an electronic component such as an IC chip using the solid film, the electronic component is pressed on the film and heated. Thereby, a film in which the electronic component is firmly adhered to the surface can be obtained.

The composition of the present invention can be advantageously used as an adhesive for die bonding. Conventionally, thermosetting epoxy resins and thermoplastic polyimide films have been used as die bonding adhesives, but none of these have been satisfactory yet. In the case of a thermosetting epoxy resin, since it is in a liquid state before curing, there is a problem that the resin sticks to the side of the Si chip at the time of heat curing, and a low-molecular-weight low-boiling additive volatilizes at the time of heat curing, causing the Si chip to harden. Including the problem of contamination. On the other hand, in the case of a thermoplastic polyimide film, there is a problem that its melting temperature is high and its cost is high. By performing die bonding using the composition of the present invention, any of the above disadvantages can be solved.

[0016]

Next, the present invention will be described in more detail with reference to examples.

Example 1 A liquid epoxy resin composition having the component composition (parts by weight) shown in Table 1 was prepared, and the composition was cast on a glass plate in the form of a liquid film.
The composition was irradiated with ultraviolet rays to evaluate the solid film forming property of the composition. In this case, UV irradiation was performed using a high-pressure mercury lamp,
The irradiation was performed for 10 seconds at an irradiation intensity of 00 mJ / cm ² . The state of the composition in the form of a solid film was observed and evaluated. Table 1 shows the evaluation results. The evaluation criteria in this case are as follows. ：: A solid film with no stickiness was obtained. Δ: A solid film is formed, but soft and sticky. X: No solid film is formed. To evaluate the thermosetting property of the composition,
Heated at 00 ° C. for 20 seconds. In this case, regarding the obtained cured product, those whose glass transition point almost reached the saturation point were evaluated as ○, and those not so evaluated as ×. Table 1 shows the results. Further, in order to evaluate the storage stability of the composition, the composition was stored at 40 ° C. for 3 days, and the ratio between the viscosity of the composition after storage and the initial viscosity before storage was examined. evaluated. Table 1 shows the results. ：: The viscosity ratio is less than 2. Δ: The viscosity ratio is 2 to 3. ×: The viscosity ratio exceeds 3.

[0018]

[Table 1]

The specific contents of the materials indicated by the trade names in Table 1 are as follows. (1) Epoxy resin Bispher AD liquid epoxy resin (2) Latent curing agent A imidazole-based, active temperature 80 ° C, “NOVACURE HX3
741 "(manufactured by Asahi Kasei Corporation) (3) Latent curing agent B 2,4-diamino-6- [2'-methylimidazolyl-
(1) '] -ethyl-s-triazine / isocyanuric acid adduct, active temperature 120 ° C, (4) latent curing agent C imidazole, active temperature about 70 ° C, "Amicure PN2
3 "(manufactured by Ajinomoto Co.) (5) Latent curing agent D dicyandiamide, activation temperature about 200 ° C (6) HY956 non-latent curing agent, modified aliphatic polyamine, activation temperature about 10
(7) ST86PA Silicone defoamer, manufactured by Toray Dow Corning Co. (8) Photo-radical generator hydroxycyclohexyl phenyl ketone (9) Monomer A Phenoxyethyl acrylate (monofunctional acrylate) (10) Monomer B Neopentyl glycol diacrylate (bifunctional acrylate) (11) Monomer C Trimethylolpropane triacrylate (trifunctional acrylate) (12) Monomer D Ditrimethylolpropane tetraacrylate (tetrafunctional acrylate) (13) Monomer E di Pentaerythritol pentaacrylate (pentafunctional acrylate) (14) Monomer F Dipentaerythritol hexaacrylate (hexafunctional acrylate)

As can be seen from the results shown in Table 1, when acrylates having three or less functions are used (Comparative Examples 1 to 3), the film-forming properties of the composition are poor, while the activation temperature is lower than 80 ° C. When a latent curing agent is used (Comparative Examples 4 to
In 5), the storage stability of the composition is poor.

[0021]

The composition of the present invention has photo-curing properties and thermosetting properties and is excellent in storage stability. The composition of the present invention is advantageously applied in the field of electric and electronic components as a liquid adhesive and a film adhesive, and is particularly advantageously used as an adhesive for die bonding.

Claims (5)

[Claims] 1. An epoxy resin comprising: (i) a liquid epoxy resin; (ii) a latent curing agent having an activation temperature of 80 ° C. or higher; and (iii) a photopolymerizable compound having four or more (meth) acryloyl groups in a molecule. Epoxy resin composition. 2. The composition according to claim 1, which contains a radical generator. 3. The composition according to claim 1, which contains a filler. 4. A solid polymer of a polymerizable compound having four or more (meth) acryloyl groups in a molecule, a liquid epoxy resin contained in the solid polymer, and a solid polymer in the solid polymer. A thermosetting resin film comprising a latent curing agent having an activation temperature of 80 ° C. or higher. 5. A step of forming a coating layer comprising the composition according to claim 1 on a substrate, and a step of irradiating the coating layer with actinic rays to form a thermosetting resin film layer. Forming a cured resin film layer by heating the thermosetting resin film layer to form a cured resin film layer.