JPH09151334A - Protection material composition for electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition composed of an acrylic functional organopolysiloxane and a photopolymerization initiator, curable by ultraviolet irradiation and heating and useful for forming a cured coating film having high hardness and excellent adhesivity to an organic resin for electronic parts. SOLUTION: The objective composition contains (A) 100 pts.wt. of an acrylic functional organopolysiloxane consisting of a unit of the formula R<1> SiO3/2 [R<1> is a group of the formula (R<5> is H or methyl; (k) is an integer of 1-10)], a unit of the formula R<1> R<2> a SiO(3-a)/2 (R<2> is OH; (a) is 1 or 2), a unit of the formula R<2> b R<3> c SiO(4-b-c)/2 (R<3> is a univalent hydrocarbon group; (b) is 1 or 2; (c) is 0, 1 or 2) and a unit of the formula R<3> d SiO(4-d)/2 ((d) is 0, 1 or 2) wherein the amount of R<2> is 3-90mol% based on the total molar number of R<1> to R<3> , (B) 0.01-25 pts.wt. of a photpolymerization initiator and, preferably, (C) 0.01-5 pts.wt. of an organic peroxide (preferably di-t-butyl peroxide).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective material composition for electronic parts, and more specifically, it has a high hardness by being cured by irradiation with ultraviolet rays and heating, and has excellent adhesiveness to an organic resin used in electronic parts. The present invention relates to an electronic component protective material composition capable of forming a cured film.

[0002]

2. Description of the Related Art Conventionally, many compositions have been proposed as a UV-curable silicone composition containing an acrylic functional organopolysiloxane as a main component. For example, a composition comprising an acrylic functional silicone resin (JP-A-61-1)
11330), a composition comprising colloidal silica, a polyfunctional acrylate monomer and a hydrolyzate of acrylate silane (see JP-A-58-1756), an acrylic functional silicone resin and a polyfunctional acrylate monomer. A composition consisting of (Japanese Patent Publication No. 6-293
No. 82) and the like are known. However, these compositions have low hardness of the film formed after curing, and in particular,
Because of poor adhesion to organic resins used in electronic components, such as epoxy resin, which is a semiconductor encapsulating resin, its use as a protective material for electronic components has been limited.

[0003]

The present inventor has reached the present invention as a result of extensive studies to solve the above problems.
That is, an object of the present invention is to cure by ultraviolet rays and heating to form a film having high hardness, and particularly to form a cured film having excellent adhesiveness to a resin for semiconductor encapsulation used in electronic parts. It is to provide an electronic component protective material composition to be obtained.

[0004]

Means for Solving the Problems The above-mentioned objects are represented by the formula (A), R
A unit represented by ¹ SiO _3/2 , a formula, R ¹ R ² _a SiO _{(3-a) / 2}
An acrylic functional organopolycomprising a unit represented by the formula: R ² _b R ³ _c SiO _{(4-bc) / 2} and a unit represented by the formula: R ³ _d SiO _{(4-d) / 2} Siloxane [wherein R ¹ is a formula

Embedded image (In the formula, R ⁵ is a hydrogen atom or a methyl group, and k is 1
Is an integer of 10 to 10. ), R ² is a hydroxyl group, R ³ is a monovalent hydrocarbon group, and a and b
Is 1 or 2, c and d are 0, 1 or 2, and the ratio of R ¹ to the total number of moles of R ¹ , R ² and R ³ is 2
˜80 mole percent, and the ratio of R ² to the total number of moles of R ¹ , R ² , and R ³ is ³ to 90 mole percent. ] 100 parts by weight and (B) photopolymerization initiator 0.01-
It is achieved by an electronic component protective material composition comprising 25 parts by weight.

[0005]

DETAILED DESCRIPTION OF THE INVENTION As used in the present invention as the component (A) acrylic functional organopolysiloxanes are those having an acrylic group and a hydroxyl group at the same time, wherein, R ¹ SiO
A unit represented by _3/2 , a formula, a unit represented by R ¹ R ² _a SiO _{(3-a) / 2} , a formula, a unit represented by R ² _b R ³ _c SiO _{(4-bc) / 2} , and a formula , R ³ _d SiO _{(4-d) / 2} . In the above formula, R ¹ is a formula

Embedded image Is a group represented by. Here, in the formula, R ⁵ is a hydrogen atom or a methyl group, and preferably a methyl group. ) K
Is a positive number from 1 to 10, and is preferably 3. R ² is a hydroxyl group. R ³ is a monovalent hydrocarbon group exemplified by an alkyl group such as a methyl group, an ethyl group and a propyl group, an aryl group such as a phenyl group and a tolyl group, and an aryl group such as a phenyl group. Of these, a phenyl group is preferable. a and b are 1 or 2, and c and d are numbers of 2 or less. The ratio of R ¹ to the total number of moles of R ¹ , R ² and R ^{3 in} the organopolysiloxane is 2 to 80 mol%, preferably 10 to 60.
It is a mole percentage. This is because if it is less than 2 mol%, good curing characteristics cannot be obtained. R ¹ , R ² ,
The ratio of R ² to the total number of moles of R ³ is ³ to 90 mol%, preferably 10 to 70 mol%. This is because if it is less than 3 mol%, good adhesive strength cannot be obtained. The R ¹ SiO _3/2 unit in this organopolysiloxane has the functions of increasing the hardness and the toughness of the cured product and increasing the hardness of the R ¹ R ² _a SiO ^2.
_{The (3-a) / 2} unit has the effect of increasing the crosslink density of the hardness of the cured product. The R ³ _d SiO _{(4-d) / 2} unit has the effect of increasing the hardness of the cured product and, when R ³ is a phenyl group, increasing the curing rate of the composition of the present invention. Such organopolysiloxanes include, for example, acryloxyalkyltrichlorosilanes such as methacryloxypropyltrichlorosilane and acryloxypropyltrichlorosilane,
It can be easily produced by dehydrochlorination polycondensation of an organosilane such as diphenyldihydroxysilane or methylphenyldihydroxysilane in an organic solvent.

The photopolymerization initiator of the component (B) used in the present invention functions to accelerate the polymerization reaction of the acrylic functional organopolysiloxane of the component (A) and accelerate the curing of the composition of the present invention. . Examples of the photopolymerization initiator include acetophenone, propiophenone, benzophenone, xanthol, benzaldehyde, 4-methylacetophenone,
3-pentylacetophenone, 4-methoxyacetophenone, 3-bromoacetophenone, 4-allylacetophenone, 3-methoxybenzophenone, p-chlorobenzophenone, 4-dimethoxybenzophenone, 4-chloro-4-benzylbenzophenone, 3-chloroxanthol, Benzoin, benzoin methyl ether, benzoin-n-butyl ether, benzoin-i-butyl ether, bis (4-dimethylaminophenyl) ketone,
Benzyl methoxy ketal, diethyl acetophenone,
2,2-dimethoxy-2-phenylacetophenone, diethoxyacetophenone and the like can be mentioned. The content of this component is 0.01 to 25 parts by weight, preferably 0.1 to 100 parts by weight of the organopolysiloxane (A).
To 10 parts by weight.

The composition of the present invention comprises the above-mentioned components (A) and (B).
Consist of components (A) and (B)
In addition to the components, it is preferable to add and blend an organic peroxide as the component (C) in order to further accelerate the curing. Examples of the organic peroxide include benzoyl peroxide, dimethylbenzoyl peroxide,
Chlorobenzoyl peroxide, dichlorobenzoyl peroxide, di-t-butyl peroxide, 2,
5-di-t-butylperoxybutyl-2,5-dimethylhexane, 2,5-di-t-butylperoxybutyl-2,5-dimethylhexyne, t-butylcumyl peroxide, dicumyl peroxide , T-butylperoxybenzoate, t-butylperoxy-4-chlorobenzoate, t-butylperoxy-2,4-dichlorobenzoate, t-butylperoxy-4-toluoate, 1,1-di (t- Butylperoxy) cyclohexane, 1,1-di (t-butylperoxy) -3,3,5
Examples include -trimethylcyclohexane and 2,2-di (t-butylperoxy) butane. Among these, compatible di-t-butyl peroxide is preferable.
The amount of the organic peroxide blended is 0.01 to 5 with respect to 100 parts by weight of the organopolysiloxane as the component (A).
Parts by weight.

The composition of the present invention comprises the above-mentioned components (A) and (B).
Component or component (A), component (B) and component (C) can be easily produced by uniform mixing. In addition to these components, a diluent for improving the coating property on the substrate As a solvent, a reactive diluent may be added. Examples of the solvent include organic solvents such as toluene, xylene and butyl lactate. Examples of reactive diluents include monofunctional acrylates, difunctional acrylates, and polyfunctional acrylates.

A photosensitizer may be added to the composition of the present invention in order to accelerate the curing reaction by ultraviolet irradiation. Examples of the photosensitizer include dyes such as 4-methyl-7- (N, N-dimethylamino) -coumarin, ketone-based or ether-based compounds such as acetophenone, and quinone-based compounds such as benzoquinone. Further, an adhesion-imparting agent may be added to improve the adhesiveness with the base material. Examples of such an adhesive include alkoxysilanes such as γ- (2-aminoethyl) aminopropyltrimethoxysilane.

When the composition of the present invention is applied to an electronic component, the composition of the present invention can be applied to the surface of the electronic component, and the composition can be cured by irradiation with ultraviolet rays or heating. In this case, it is preferable to irradiate the composition with ultraviolet rays to cure the composition and then heat the composition to complete the curing. Here, the ultraviolet irradiation device for irradiating ultraviolet rays is not particularly limited, and a hydrogen discharge tube,
Examples thereof include a high pressure mercury lamp, a medium pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp and a carbon arc lamp. Moreover, as a device for heating, a heating device such as a hot air circulation type oven, a hot plate, and an infrared irradiation device is exemplified.

The composition of the present invention as described above is rapidly cured by ultraviolet rays and heating to form a film having high hardness, and in particular, it is excellent in adhesiveness to an organic resin used in electronic parts. Since it forms a film, it is preferably used as a protective material for various electronic components. Examples of protected electronic components include semiconductor elements, hybrid ICs, printed circuit boards, and liquid crystal display boards.

[0012]

EXAMPLES Next, the present invention will be described in detail with reference to Examples and Reference Examples. In the examples, “parts” means “parts by weight”.

[0013]

[Reference Example 1] In a four-necked flask equipped with a stirrer, a dropping funnel, a fractionating tube and a thermometer, 525 parts of γ-methacryloxypropyltrichlorosilane, 3124 parts of toluene, p
-Methylphenol (0.047 parts) was added and the mixture was stirred. Then, a mixed liquid of 329 parts of diphenyldihydroxysilane and 708 parts of triethylamine was gradually added dropwise to this reaction system, and this reaction system was stirred at 80 ° C. for 2 hours. Then, a small amount of aqueous hydrochloric acid solution was added to this system, and the mixture was reacted by stirring. Then, the toluene layer was separated, the reaction product was washed with water several times, and then the toluene layer was heated under reduced pressure to prepare 439 g of a colorless transparent viscous liquid. This viscous liquid
As a result of analysis by ¹³ C-nuclear magnetic resonance spectrum, ²⁹ Si-NMR and infrared spectroscopy, it was confirmed to be an organopolysiloxane represented by the following average unit formula. Also,
As a result of analyzing this organopolysiloxane by gel permeation chromatography, its weight average molecular weight was 1,700 in terms of polydimethylsiloxane.

Embedded image In the above formula, R ¹ is a group represented by the following chemical structural formula.

[Chemical 6]

[0014]

Example 1 65 parts by weight of the methacryloxyalkyl-functional organopolysiloxane obtained in Reference Example 1, 5 parts by weight of benzoin-iso-butyl ether and 29 parts by weight of butyl lactate were uniformly mixed to prepare a composition for protecting electronic parts. Was prepared. This composition was applied on a glass plate and dried to form a thin film on the glass plate. The thin film was irradiated with ultraviolet light having a light amount of 100 mJ / cm ² by a conveyor type ultraviolet irradiation device, and then further heated at 250 ° C. for 1 hour. When the hardness of the obtained cured film was measured, it was found that this cured film had a pencil hardness of 3H. In addition, this electronic component protective material composition has a film thickness of 20 μm on the semiconductor surface.
m and apply it with a conveyor type UV irradiator to irradiate it with UV light with a light intensity of 100 mJ / cm ² , and then further 2
It was cured by heating at 50 ° C. for 1 hour. Then, an epoxy resin for semiconductor encapsulation (bisphenol type epoxy resin) was applied thereon to a thickness of 1 mm, and heated at 180 ° C. to cure. After that, the cured epoxy resin was peeled off from the semiconductor, and the peeled surface was examined, and the cured film of the electronic component protective material composition was firmly adhered to the cured epoxy resin, and peeled off even if the interface was rubbed with a nail. There wasn't.

[0015]

Example 2 65 parts by weight of methacryloxyalkyl-functional organopolysiloxane obtained in Reference Example 1, 5 parts by weight of benzoin-iso-butyl ether, butyl lactate 29
By weight, 1 part by weight of di-t-butyl peroxide was uniformly mixed to prepare an electronic component protective material composition. This composition was applied on a glass plate and dried to form a thin film on the glass plate. The thin film was irradiated with ultraviolet light having a light amount of 100 mJ / cm ² by a conveyor type ultraviolet irradiation device, and then further heated at 250 ° C. for 1 hour. When the hardness of the obtained cured film was measured, it was found that this cured film had a pencil hardness of 4H. Further, this electronic component protection material composition was applied on the surface of a semiconductor so as to have a film thickness of 20 μm, and a light amount of 1 was applied by a conveyor type ultraviolet irradiation device.
After irradiating with ultraviolet rays of 00 mJ / cm ² , it was further cured by heating at 250 ° C. for 1 hour. Then, an epoxy resin for semiconductors (bisphenol type epoxy resin) was applied from above, and heated at 180 ° C. to cure. Then, the cured epoxy resin was peeled off from the semiconductor, and the peeled surface was examined. As a result, the cured organopolysiloxane film was firmly adhered to the epoxy resin and was not peeled off even if the interface was rubbed with a nail.

[0016]

The electronic component protective material composition of the present invention is (A)
Component and (B) component or (A) component, (B) component and
Since it is composed of the component (C), it has a feature that it can be cured by ultraviolet rays and heating to form a cured film having high hardness and excellent adhesiveness to an organic resin used in electronic parts. .

Claims (3)

[Claims] 1. A unit represented by the formula (A), R ¹ SiO _3/2 ,
Formula, unit represented by R ¹ R ² _a SiO _{(3-a) / 2} , Formula, R ² _b R
Units and formulas represented by ³ _c SiO _{(4-bc) / 2} , R ³ _d Si
Acrylic functional organopolysiloxane consisting of units represented by O _{(4-d) / 2} [wherein R ¹ is of the formula: (In the formula, R ⁵ is a hydrogen atom or a methyl group, and k is 1
Is an integer of 10 to 10. ), R ² is a hydroxyl group, R ³ is a monovalent hydrocarbon group, and a and b
Is 1 or 2, c and d are 0, 1 or 2, and the ratio of R ¹ to the total number of moles of R ¹ , R ² and R ³ is 2
˜80 mole percent, and the ratio of R ² to the total number of moles of R ¹ , R ² , and R ³ is ³ to 90 mole percent. ] 100 parts by weight and (B) photopolymerization initiator 0.01-
An electronic component protection material composition comprising 25 parts by weight. 2. A unit represented by the formula (A), R ¹ SiO _3/2 ,
Formula, unit represented by R ¹ R ² _a SiO _{(3-a) / 2} , Formula, R ² _b R
Units and formulas represented by ³ _c SiO _{(4-bc) / 2} , R ³ _d Si
Acrylic functional organopolysiloxane consisting of units represented by O _{(4-d) / 2} [wherein R ¹ is of the formula: (In the formula, R ⁵ is a hydrogen atom or a methyl group, and k is 1
Is an integer of 10 to 10. ), R ² is a hydroxyl group, R ³ is a monovalent hydrocarbon group, and a and b
Is 1 or 2, c and d are 0, 1 or 2, and the ratio of R ¹ to the total number of moles of R ¹ , R ² and R ³ is 2
˜80 mole percent, and the ratio of R ² to the total number of moles of R ¹ , R ² , and R ³ is ³ to 90 mole percent. ] 100 parts by weight, (B) photopolymerization initiator 0.01-25
An electronic component protective material composition comprising 0.01 part by weight and (C) 0.01 to 5 parts by weight of organic peroxide. 3. The electronic component protective material composition according to claim 1, wherein R ³ is a phenyl group.