JP2854749B2 - UV / Heat curable solder resist ink composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet / heat curable solder resist ink composition which is excellent in heat resistance, gold plating resistance and electric insulation used for a printed wiring board.

[0002]

2. Description of the Related Art In the field of printed wiring boards in recent years, the density of a printed wiring board has been increased, and the demand for a liquid photo-solder resist has been accordingly increased. However, the screen printing method has been applied in view of productivity and cost. ing. Conventionally, thermosetting solder resist ink compositions have been used for those with strict reliability requirements, and ultraviolet curable solder resist ink compositions have been used for those where productivity is important. . By the way, the thermosetting type has a problem that the curing time is long and the productivity is inferior, and that the heat exerts an adverse effect on the substrate, in particular, the dimensional accuracy is inferior and warpage occurs. Further, since the organic solvent is contained as an essential component, it has a problem of working environment, generation of voids and bleeds, and adverse effects on electric corrosion. On the other hand, the ultraviolet curing type hardly has the above-mentioned problems, but is inferior in reliability. Further, it is also well known to improve the properties by post heat treatment of the ultraviolet curable solder resist ink, the properties are not reached until the level of the heat-curable solder resist ink. From these viewpoints, development of a solder resist ink having both productivity and reliability is desired.

[0003] Techniques for curing by using both ultraviolet light and heat are widely used in various fields such as paints, adhesives, molded products, and the like, and are also applied to chip adhesives, potting agents and the like in printed wiring boards. in use. For example, Japanese Patent Application Laid-Open No. 53-14247 discloses a method in which an epoxy resin is cured with cations generated by ultraviolet rays and further thermally cured.
Nos. 7 and 61-272228 disclose a method of using a partially vinyl esterified epoxy resin, and JP-A-63-238174 discloses a method of combining an epoxy resin and an ultraviolet radical curable resin. It has been disclosed.

[0004]

[0007] However, the JP 53-142447, the technique disclosed in the 60-208377 Patent and the 61-272228 JP Sol
When used for a solder resist, there are fundamental problems such as curability, adhesion, and cost, and the properties required for the solder resist have not yet been satisfied. Further, the one disclosed in Japanese Patent Application Laid-Open No. 63-23817 has a problem that the strength of the coating film after ultraviolet curing is weak, and that the coating is easily damaged during operation. Further, since a compound having two or more polymerizable double bonds in one molecule is used as an unsaturated compound, if a large amount of the unsaturated compound is used, the thermosetting property is deteriorated and the final coating is performed. There was a problem that the resistance of the film was poor. Further, if the working viscosity of the resist ink is not reduced, the printing workability is significantly restricted, so that an organic solvent is necessary. Therefore, not only the touch drying property during ultraviolet curing is reduced, but also the voids are reduced. There is also a problem that the occurrence and the electrolytic corrosion are remarkably deteriorated.

Accordingly, an object of the present invention is to solve the above-mentioned problems in the conventional technology. That is, an object of the present invention is to form a resist film that is cured by ultraviolet light and heat without using an organic solvent, and has excellent coating strength after ultraviolet curing , and is formed after thermal curing. The resist film has excellent adhesion, solder heat resistance,
Ultraviolet light with electroless gold plating resistance, electrolytic corrosion and hardness
An object of the present invention is to provide a heat-curable solder resist ink composition.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of the above-mentioned problems, and as a result, as an ultraviolet curing component, one acryl group or metal compound in one molecule.
Using an acrylate or methacrylate compound having a ril group and having one or more hydroxyl groups as an essential component,
By using a specific epoxy curing agent in combination and making the ratio of the ultraviolet curing component and the thermosetting component 50% or more of the ultraviolet curing component, the strength of the coating film after the ultraviolet curing is increased and the post-thermosetting property is deteriorated. Without any problem, it was found that the productivity was good, and that the characteristics equal to or higher than those of the thermosetting solder resist ink were obtained, and the present invention was completed.

[0007] That is, the curable solder resist ink composition of the present invention is a combination of ultraviolet light and heat,
-1) have at least two acrylate or methacrylate groups per molecule, A no carboxyl group
A acrylate or methacrylate compound,
Line curable monomer or oligomer, (A-2) in a molecule
Has one acrylic or methacrylic group, and one or more
Acrylate or methacrylate compound having a hydroxyl group, (B) a photopolymerization initiator, (C) mainly made of epoxy resin, and (D) an epoxy curing agent having at least one epoxy group in one molecule, the epoxy hard
The dicyandiamide or a derivative thereof,
Rare or a derivative thereof, wherein component (A-1) + component (A-2): component (C) is 5% by weight.
0:50 to 95: 5, and the component (A-
2) is characterized in that the total solid content is 10% by weight or more.

Hereinafter, the curable solder resist ink composition of the present invention will be described in detail. In the present invention, the ultraviolet-curable component comprises the component (A-1) and the component (A-2), and the compounding amount thereof is based on the weight ratio to the epoxy resin of the thermosetting component (C). At 5
It is necessary that the ratio be in the range of 0:50 to 95: 5, and it is preferable to blend in the range of 60:40 to 80:20. When the ratio of the UV-curable component is lower than 50:50, the strength of the coating film after UV- curing becomes weak, and the ratio of 95:
If the value is higher than 5, problems occur in terms of reliability, corrosion resistance, electrolytic corrosion, and the like.

[0009] In the present invention, it has at least two acrylate or methacrylate groups in one molecule of the component to be used as one of the ultraviolet curable component (A-1), mosquitoes
Acrylates or methacrylates without ruboxyl groups
A UV-curable monomer ,
The following are exemplified. Polyhydric alcohol poly (meth)
Acrylates (hereinafter, both acrylate and methacrylate are abbreviated as “(meth) acrylate”),
For example, ethylene glycol di (meth) acrylate,
Propylene glycol di (meth) acrylate, 1,4
-Butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol diacrylate (for example, Nippon Kayaku Co., Ltd.)
Manufactured by: HDDA), 1,6-hexanediol dimethacrylate, diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate,
Polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane triacrylate (Toa Gosei Chemical Industry Co., Ltd .: Aronic M-309, Nippon Kayaku Co., Ltd.):
Kayahard TMPTA), trimethylolpropane trimethacrylate, glycerin tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta- or hexa (meth) acrylate, trismethacryloyloxyethyl isocyanurate, trisacryloyloxy isocyanurate ( Toa Gosei Chemical Industry Co., Ltd .: Aronic M-
215) and the like. As the acrylate oligomer, an acrylic acid or methacrylic acid adduct of an epoxy resin, for example, a diacrylate of a bisphenol A type epoxy resin (TOHRAD-3 manufactured by Toto Kasei KK)
700), phenol novolak type epoxy resin diacrylate (TOHRAD-632, manufactured by Toto Kasei Co., Ltd.)
23 and SP-4010 manufactured by Showa Polymer Co., Ltd., diacrylate of bisphenol F type epoxy resin (SP-1506 manufactured by Showa Polymer Co., Ltd.), terminal isocyanate obtained by previously reacting a diisocyanate compound with a polyol In a molecule obtained by reacting an alcoholic hydroxyl group-containing (meth) acrylate with a group-containing compound,
A urethane acrylate oligomer having at least two (meth) acryloyloxy groups (for example, Alonik M-1100, M-1200, manufactured by Toa Gosei Chemical Industry Co., Ltd.),
Oligoester acrylate in which a (meth) acryloyl group is introduced into a terminal of a polyester resin synthesized from a dihydric or trihydric alcohol and a dibasic acid (for example, Alonik M-6100, Aronic M, manufactured by Toa Gosei Chemical Industry Co., Ltd.) -6300, ARONIC M-8030, ARONIC M-8060) and the like.

One molecule of the component (A-2), which is another component of the ultraviolet-curable component, has one acryl group or one
Acrylate having one or more hydroxyl groups having a ril group
Alternatively, as the methacrylate compound, 2-hydroxy-3-phenoxypropyl (meth) acrylate,
Examples include hydroxyethyl acrylate, 2-hydroxyethyl methacrylate (light ester HO: manufactured by Kyoeisha Yushi Co., Ltd.), and 2-hydroxypropyl (meth) acrylate.

In the present invention, the component (A-2) needs to be at least 10% by weight or more of the total solids, and preferably in the range of 10 to 20% by weight. (A
When the blending amount of -2) is lower than 10% by weight, adhesion after ultraviolet curing becomes a problem.

Known photopolymerization initiators are used as the component (B). For example, ketals such as benzyl methyl ketal (manufactured by Ciba Geigy: Irgacure 651), benzoins such as benzoin methyl ether, benzoin ethyl ether, benzoin-1-propyl ether, benzoin and α-methylbenzoin;
10-anthraquinone, 1-chloroanthraquinone, 2
-Anthraquinones such as -chloroanthraquinone and 2-ethylanthraquinone; benzophenones such as benzophenone, p-chlorobenzophenone and p-dimethylaminobenzophenone; 2-hydroxy-2-methylpropiophenone (Darocur 1173, manufactured by Merck);
-(4-isopropylphenyl) -2-hydroxy-2
-Methylpropiophenone (Merck: Darocu)
r1116) and other propiophenones, 2-methyl-1
-[4- (methylthio) phenyl] -2-morpholinopropanone-1 (manufactured by Ciba Geigy : Irgacure 9)
07) can be used. Component (B) is used in an amount of 0.1 to 20 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the ultraviolet curing component.

In the present invention, the epoxy resin of component (C) which is a thermosetting component includes bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, alicyclic epoxy resin, phenol novolak type epoxy resin. Epoxy resins, cresol / novolak epoxy resins, resorcinol / diglycidyl ether, xylene resin-modified novolak epoxy resins, bisphenol S-modified epoxy resins, bisphenol A-modified novolak epoxy resins, glycidylamines, and the like can be used.

As specific examples of these, as a bisphenol A type epoxy resin, Epicoat 828, Epicoat 834, Epicoat 1001, Epicoat 1004
(The above are manufactured by Yuka Shell Epoxy Co., Ltd.), DER-33
0, DER-331, DER-661, DER-664
(The above are manufactured by Dow Chemical Co., Ltd.), Araldite GY-26
0, Araldite GY-280, Araldite 607
1. Araldite 6084 (all manufactured by Ciba Geigy)
And the like. As a bisphenol F type epoxy resin, Epicoat 807 (Yukaka Epoxy Co., Ltd.)
And Epicron 830 (manufactured by Dainippon Ink and Chemicals, Inc.). Examples of the alicyclic epoxy resin include Araldite CY-175, Araldite CY-1
77, Araldite CY-179, Araldite CY-
184, Araldite CY-192 (all manufactured by Ciba-Geigy), ERL-4221, ERL-4209, ER
L-4299 (above, manufactured by Union Carbide Co., Ltd.) and Epicoat 171 (manufactured by Yuka Shell Epoxy Co., Ltd.).

As the bisphenol AD type epoxy resin, Epomic R-710 (Mitsui Petrochemical Co., Ltd.)
Made) is a typical example. In addition, as a phenol novolak type epoxy resin, Epicoat 1
52, Epicoat 154 (Yuka Kasper Epoxy Co., Ltd.)
Manufactured by Araldite EPN-1138, Araldite E
PN-1139 (above, manufactured by Ciba Geigy), Epicron N-738, and Epicron N-770 (manufactured by Dainippon Ink and Chemicals, Inc.). Cresol novolak type epoxy resins include EOCN-102S, EO
CN-103, EOCN-104 (all manufactured by Nippon Kayaku Co., Ltd.), Epicron N-665, Epicron N-6
73 (manufactured by Dainippon Ink and Chemicals, Inc.).
As xylene resin-modified novolak epoxy resin,
Epicron EXA-1857 (manufactured by Dainippon Ink and Chemicals, Inc.) can be mentioned. Examples of bisphenol A-modified novolak type epoxy resin include epicron N-865 and epicron N-880 (manufactured by Dainippon Ink and Chemicals, Inc.)
Examples of the bisphenol S-modified novolak epoxy resin include Epiclon EXA-4004 (manufactured by Dainippon Ink and Chemicals, Inc.). Examples of the resorcinol-modified novolak epoxy resin include Epicron N.
-510. Further, as glycidylamines, Sumiepoxy ELN-125, Sumiepoxy EL
N-120, Sumiepoxy ELN-434 (all manufactured by Sumitomo Chemical Co., Ltd.) and TETRAD-X (Mitsubishi Gas Chemical Co., Ltd.).

As the epoxy resin curing agent of the component (D), imidazole compounds, dicyandiamide, biguanide compounds, organic acid anhydrides, polyhydric phenol compounds and the like are preferably used .
Is dicyandiamide or a derivative thereof and bisurea
Alternatively, it is necessary to use a derivative thereof in combination. Departure
Specifically, the epoxy resin curing agents used specifically include imidazole compounds such as Curezole 2MZ, Curezol 2E4MZ, Curezol 2PZ, Curezol C11Z, Curezol 1B2MZ, Curezol 2
MZ-CN, Curezol 2E4MZ-CN, Curezol 2PZ-CN, Curezol MZ-AZINE, Curezol 2E4MZ-AZINE, Curezol C1
1Z-AZINE, Curezol AMZ, Curezol 2PHZ, Curezol 2P4MHZ, Curezol 2
PHZ-CN, Cureazole 2E4MZ-BIS (all manufactured by Shikoku Chemicals Co., Ltd.), carboxylate of the imidazole compound, salt of the imidazole compound and a mono- or polyhydric phenol compound, isocyanurate of the imidazole compound ( Manufactured by Shikoku Chemical Industry Co., Ltd .: Cureazole 2MZ-OK, Cureazole 2PZ-OK, Curesol 2MA-OK), adducts of the above imidazole compounds with monoepoxy compounds or epoxy resins, and adducts of these with polyhydric phenol compounds Salt and the like.

As the biguanide compound, o-toluyl biguanide (manufactured by Ouchi Shinko Chemical Co., Ltd .: Noxeller B)
G), cyanoethylated o-toluyl biguanide, o
-Monoepoxy adducts and epoxy resin adducts of tolylbiguanide. Examples of the organic acid anhydride include Epicron B4400 (manufactured by Dainippon Ink and Chemicals, Inc.), 1,2,3,4-butanetetracarboxylic dianhydride, and long-chain dibasic acid anhydride (Okamura Oil Co., Ltd.) Made: I
PU-22AH, SB-20AH) and the like. Examples of the polyhydric phenol compound include pyrogallol and novolak resin (for example, BRG-55 manufactured by Showa Polymer Co., Ltd.).
8), cresol novolak resin and the like. Examples of the bisurea include an aromatic dialkyl urea, an aromatic monoalkyl urea, an alicyclic dialkyl urea, and an aliphatic dialkyl urea.
In consideration of storage stability and the like, alicyclic dialkyl ureas (for example, U-CAT3503N manufactured by San Apro) can be preferably used. Furthermore, Tris-
Tertiary amine compounds such as dimethylaminomethylphenol (K-54 manufactured by Anchor Chemical Co., Ltd.) and benzyldimethylamine can also be used.

The component (D) is used in an amount of 1 to 20 parts by weight based on 100 parts by weight of the component (C).
It is preferable to use in the range of 1 to 10 parts by weight.

The curable solder resist ink composition for combined use with ultraviolet light and heat of the present invention comprises the above components (A-1) and (A-
2) In addition to (B), (C) and (D), if necessary,
Inorganic fillers, inorganic and organic pigments for coloring, thixotropy-imparting agents for imparting appropriate printability, leveling agents and defoamers for forming smooth coating films,
A flame retardant for imparting self-extinguishing properties can be contained.

[0020]

The present invention will be described below with reference to examples , reference examples and comparative examples. “Parts” means “parts by weight” unless otherwise specified. Examples 1 and 2, Reference Examples 1 to 4 and Comparative Examples 1 to 5 Components and amounts shown in Table 1 below (numbers indicate parts).
And 60 parts of precipitated barium sulfate as a filler, 5 parts of finely divided silica, and 1 part of a coloring pigment (phthalocyanine green) were added to each mixture, and the particle diameter according to JIS K-5400 was 12.5 μm using a three-roll mill. The resulting mixture was kneaded sufficiently to obtain a resist ink composition.
The components in Table 1 are as follows.

Lipoxy SP-4010 (a phenol novolak type epoxy resin polyacrylate manufactured by Showa Polymer Co., Ltd.) Aronix M8060 (a terminal acryloyl group-introduced oligoester acrylate manufactured by Toa Gosei Chemical Industry Co., Ltd.) TOHRAD-3700 (Toto) Kasei Co., Ltd. bisphenol a type epoxy resin diacrylate) KAYAHARD TMPTA (manufactured by Nippon Kayaku Co., Ltd. of tri methylol <br/> Lumpur propane triacrylate) light ester HO (Kyoeisha Yushi Co., Ltd. 2 - hydroxyethyl methacrylate) Irgacure 651 (manufactured by Ciba-Geigy of dibenzyl
Methyl ketal) Epicoat 807 (bisphenol F type epoxy resin manufactured by Yuka Shell Epoxy Co., Ltd.) U-CAT3502T (aromatic dialkyl urea manufactured by San Apro Co.) U-CAT3503N (alicyclic dialkyl urea manufactured by San Apro Co.) Cureazole 2E4MZ (Imidazole compound manufactured by Shikoku Chemical Industry Co., Ltd.)

[0022]

[Table 1]

The characteristics of the obtained resist ink composition were evaluated as follows. That is, a circuit pattern was formed on both sides of a glass fiber reinforced epoxy resin laminate having copper clad on both sides by a conventional method, and an acid treatment, buffing, washing and drying were performed. A resist ink is applied to one surface of this epoxy resin plate by a screen printing method so as to have a film thickness of 15 to 25 μm, and an air-cooled 80 W / cm 3 lamp high-pressure mercury lamp (manufactured by Oak: HHM-8400 / E-FS) Type)
Then, after irradiating ultraviolet rays at a conveyor speed of 6 m / min, the other surface was coated with a resist ink in the same manner and irradiated with ultraviolet rays. The obtained epoxy resin plate was
A test piece was prepared by performing a heat curing treatment at 50 ° C. for 20 minutes. In the case of Comparative Example 2, the test piece was obtained by performing thermal curing on one side at 140 ° C. for 15 minutes and performing thermal curing on the other side at 140 ° C. for 20 minutes without performing ultraviolet irradiation after application of the resist ink. Was prepared.

With respect to the obtained test pieces, the properties of the coating film after curing with ultraviolet light and the coating film after curing with both ultraviolet light and heat were evaluated. Table 2 shows the results. The test conditions and evaluation criteria are as follows. 1) Dry to the touch To be measured in accordance with JIS K-5400 5.8. The sample that became dry to the touch was evaluated as ○, and the sample that did not dry to the touch was evaluated as ×. 2) Pencil hardness Measured according to JIS K-5400 6.14. 3) Adhesion In accordance with JIS D-0202, 100 1 x 1 mm grids are cut into the coating film and peeled off with cellophane tape. The result was indicated by x. The test was performed on both the copper foil and the coating film on the resin. 4) Solder heat resistance The test piece was immersed in molten solder at 260 ° C. for 30 seconds, immediately cooled under running water, and then the state of the coating film was observed.も の indicates that the coating film had no abnormality such as swelling, peeling, and melting, and X indicates that any abnormality was observed. 5) Resistance to electroless gold plating The plate was immersed in an electroless nickel plating solution at 80 ° C. for 30 minutes and then in an electroless gold plating solution at 95 ° C. for 30 minutes to perform plating (a nickel layer 3 μm and a gold layer 0.05 μm). Then, the state after sticking and peeling off a cellophane tape was observed.も の indicates that no abnormality was observed, and X indicates that the sample was peeled off. 6) Electrocorrosion The JIS Z-3197 comb electrode pattern is 60
The test piece was held in a 50 ° C., 95% relative humidity atmosphere with a direct current of 50 V applied.も の indicates that there was no abnormality for 1000 hours or more, X indicates that an abnormality such as discoloration of the conductor was observed within 100 hours, and Δ indicates that an abnormality was observed within 500 hours.

[0025]

[Table 2]

[0026]

As described above, the resist ink of the present invention can form a resist film showing curability to both ultraviolet rays and heat without using an organic solvent. The formed resist film has excellent coating strength after ultraviolet curing, and also has excellent post-heat curing properties, such as adhesion, solder heat resistance, electroless gold plating resistance, electrolytic corrosion resistance, and electrical resistance. A resist film excellent in insulation and hardness can be formed.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C09D 1/00-201/10 G03F 7/027-7/038 H05K 3/28

Claims (1)

(57) [Claims] [Claim 1] (A-1) have at least two acrylate or methacrylate groups in the molecule, carboxyl
Acrylate or methacrylate without sil group
A compound, an ultraviolet curable monomer or oligomer,
(A-2) One acryl group or methacryl in one molecule
Acrylate or methacrylate compound having one or more hydroxyl groups , (B) a photopolymerization initiator, (C)
An epoxy resin having at least one epoxy group in one molecule, and (D) an epoxy curing agent, wherein the epoxy curing agent is dicyandiamide or a dicyandiamide or the like.
Containing a derivative and bisurea or a derivative thereof
And than the component (A-1) + component (A-2): a component (C) weight ratio of 50: 50 to 95: in the range of 5,
In addition, the component (A-2) is at least 10% by weight of the total solid content, and the combined use of ultraviolet ray and heat curable solder resist ink composition.