JPS6310726B2 - - Google Patents

Description

[Detailed description of the invention]

[Field of Application of the Invention] The present invention relates to an epoxy resin composition, and in particular to a resist ink composition necessary for manufacturing printed circuit boards using electroless metal plating (chemical plating), which has excellent printability. The present invention relates to a solder resist ink composition which is excellent in the adhesion of a cured film, chemical resistance (plating liquid resistance), and heat resistance. [Prior art] Generally, the film thickness of conductor circuits on printed circuit boards is 30~
It is 35μm. Furthermore, the characteristics of the electroless metal plating film that forms this conductor circuit generally have a growth rate of 3% or more as proposed by the American Printed Circuit Board Association (IPC).
Tensile strength of 21Kg/mm or more is required. Electroless metal plating films that meet this requirement generally have a pH of 12 to 13.
It can only be obtained in a strong alkaline bath (60-80℃) at 20℃, and the deposition rate of electroless metal plating is about 0.5-5μm/h.
In order to obtain a thickness of 35 μm, it is necessary to conduct plating for a long time. Various resist films have been known to protect conductor patterns, but resist films like the one of the present invention have excellent printability, can withstand high-temperature, strongly alkaline plating solutions for long periods of time, and have good adhesion to substrates and conductors. There has been no epoxy resin composition suitable for a solder resist that can withstand soldering temperatures. [Object of the Invention] The first object of the present invention is to prevent the resin film from dissolving, whitening, cracking, or swelling even when immersed in an electroless metal plating solution for a long time, and to maintain close contact with the base material and conductor. An object of the present invention is to provide an epoxy resin composition that maintains properties. The second object of the present invention is to have excellent printability, and also to ensure that the resist film does not dissolve, whiten, crack, or swell even when immersed in an electroless metal plating solution for a long time, and that it adheres closely to the base material and conductor. An object of the present invention is to provide an ink composition for a solder resist that has excellent properties and withstands soldering work. [Summary of the Invention] For example, in a semi-additive method in which a conductor pattern formed on a substrate by an etching method is protected with a resist ink film and only the through-hole portion is formed by electroless plating, the conductor pattern connected to the through-hole is In most cases, poor adhesion occurs in the upper resist film, resulting in blisters in this area during soldering. This is because moisture infiltrates through the resist film and reduces the adhesive strength between the resist film and the conductor since the resist film is immersed in a high-temperature, strongly alkaline electroless plating solution for a long time. Therefore, the present inventors investigated various additives that improve the water resistance of adhesives, and as a result, they decided to add a modified 1-0-tolyl biguanide to the resist ink. We have found that the problem can be solved by combining 0-tolyl biguanide modified products. The epoxy resin composition of the present invention for the above purpose is characterized in that it contains (a) an epoxide compound and (b) a modified 1-0-tolyl biguanide. As the 1-0-tolylbiguanide modified product (b), an addition reaction product of 1-0-tolylbiguanide and a diepoxide compound, or
An addition reaction product of 1-0-tolylbiguanide and a polyfunctional epoxide compound is preferred. Note that the epoxy resin composition of the present invention further comprises (c)
It can contain a filler, (d) a thixotropic agent, (e) an organic solvent, and, if necessary, (f) a coloring agent and (g) an antifoaming agent. The epoxide compound (a) used in the present invention is a compound having two or more epoxy groups per molecule on average, such as polyhydric compounds such as bisphenol A, halogenated bisphenol A, catechol, resorcinol, etc. Polyglycidyl ether or polyglycidyl ester obtained by reacting a polyhydric alcohol such as phenol or glycerin with epichlorohydrin in the presence of a basic catalyst; an epoxy novolak obtained by condensing a novolak-type phenolic resin with epichlorohydrin; These include epoxidized polyolefin, epoxidized polybutadiene, dicyclopentadiene oxide, or epoxidized vegetable oil, which is epoxidized by a peroxidation method. The 1-0-tolyl biguanide modified product (b) used in the present invention is an addition reaction product of 1-0-tolyl biguanide and a diepoxide compound or a polyfunctional epoxide compound, and is represented by the following general formula. It is.

[Embodiments of the invention]

EXAMPLES Hereinafter, the present invention will be explained in more specific detail with reference to Examples and Comparative Examples. Example 1 100 parts by weight of Epicoat 152 (manufactured by Shell Kagaku Co., Ltd., novolak type epoxy resin, epoxy equivalent: 175) as an epoxide compound, 10 parts by weight of talc powder L-1 (manufactured by Nippon Talc Co., Ltd., average particle size 2 μm) as a filler, Ultrafine silicon oxide powder Aerosil as a thixotropic agent
A380 (manufactured by Nippon Aerosil) 6 parts by weight, silicone oil SC-5540 (Toray Silicone) as an antifoaming agent
2 parts by weight of phthalocyanine green as a coloring agent, and 10 parts by weight of n-butyl cellosolve as an organic solvent were sufficiently kneaded using a sieve machine and a three-roll mill to prepare a base resin. On the other hand, as a 1-0-tolyl biguanide modified product, 20 parts by weight of 1-0-tolyl biguanide, 19.9 parts by weight of Epicoat 828 (manufactured by Ciel Chemical Co., Ltd., bisphenol type epoxy resin, epoxy equivalent weight 190), n-
Mix and stir 20 parts by weight of butyl cellosolve, and heat at 80℃.
59.9 parts by weight of the addition reaction product obtained by heating for 90 minutes was mixed with the above base resin to obtain an epoxy resin composition, a so-called resist ink composition. The thixotropic index was 21 and the viscosity was 4305 poise. Here, the chemical structural formula of Epicote 828 is: It is. Conductor 0.3~20mm on copper-clad glass epoxy board,
The above resist ink composition was printed by screen printing on a printed circuit board on which a pattern with a conductor interval of 0.7 to 5 mm was formed so that a part of the conductor pattern was exposed. This was placed in a heating oven at 130°C for 30 minutes and cured. The thickness of the resist film is 10~
It was 15 μm. Next, it was immersed in the electroless copper plating solution shown below for 20 hours.

〔Effect of the invention〕

As explained above, the epoxy resin composition of the present invention is based on adding a modified 1-0-tolyl biguanide to an epoxide compound, and further adding a filler, a thixotropic agent, and an organic solvent. By adding colorants and antifoaming agents accordingly, we can improve adhesion to the base material and have excellent resistance to plating liquids.
Furthermore, it has good solder heat resistance and can be used as a solder resist ink.

Claims (1)

[Scope of Claims] 1 Contains an epoxide compound and a 1-0-tolyl biguanide modified product, and the 1-0-tolyl biguanide modified product contains an epoxide compound represented by the following general formula [] and a 1-0-tolyl biguanide modified product. 0
- An epoxy resin composition characterized in that it is a compound represented by the following general formula [] which is an addition reaction product with tolylbiguanide. Here, R represents a structure selected from the following formulas (a) to (d).