Curable resin composition for pore filling
阅读说明：本技术 填孔用固化性树脂组合物 (Curable resin composition for pore filling ) 是由 金泽康代 佐佐木光 于 2020-03-24 设计创作，主要内容包括：本发明为填孔用固化性树脂组合物。[课题]提供：适合作为印刷电路基板的通孔或导通孔的填孔用的固化性树脂组合物。[方案]一种填孔用固化性树脂组合物,其至少含有下述成分(A)～(C)：(A)双酚E型环氧树脂、(B)3官能以上的环氧树脂、和(C)多胺型固化剂,且所述填孔用固化性树脂组合物的依据JIS-C2161：2010测得的、100℃下的胶凝时间为30分钟以下。(The present invention relates to a curable resin composition for pore filling. [ problem ] to provide: the curable resin composition is suitable for filling through holes or via holes in printed circuit boards. [ solution ] A curable resin composition for pore filling, which contains at least the following components (A) to (C): (A) bisphenol E type epoxy resin, (B) epoxy resin with 3 or more functions, and (C) polyamine type curing agent, wherein the curable resin composition for pore filling has a composition ratio of (A) to (B) according to JIS-C2161: the gel time at 100 ℃ measured in 2010 is 30 minutes or less.)
1. A curable resin composition for pore filling, which contains at least the following components (A) to (C):
(A) bisphenol E type epoxy resin,
(B) An epoxy resin having 3 or more functional groups, and
(C) a polyamine-type curing agent which is a polyamine-type curing agent,
and the curable resin composition for pore filling has a composition according to JIS-C2161: the gel time at 100 ℃ measured in 2010 is 30 minutes or less.
2. The curable resin composition for pore filling according to claim 1, wherein the polyamine-type curing agent (C) has a curing initiation temperature of 95 ℃ or lower.
3. The curable resin composition for pore filling according to claim 1 or 2, further comprising an imidazole-type curing agent.
4. The curable resin composition for pore filling according to any one of claims 1 to 3, further comprising an inorganic filler.
5. A cured product comprising the curable resin composition for hole filling according to any one of claims 1 to 4.
6. An electronic component comprising the cured product according to claim 5.
Technical Field
The present invention relates to a curable resin composition, particularly to a curable resin composition for use in filling holes in through holes or via holes of printed circuit boards.
Background
In order to cope with an increase in the mounting density of components and complication of circuit wiring, a multilayer printed circuit board is formed by alternately laminating an insulating layer made of an insulating resin and a conductive layer on which a conductive pattern is printed. Then, plated through holes are formed so as to penetrate the plurality of conductive layers and the insulating layer.
Further, development of a resin composition for filling holes for filling the holes of the through-holes is inevitably desired, and a technique for dealing with the development has been proposed.
For example,
Disclosure of Invention
Problems to be solved by the invention
When the resin composition for via is filled in the via hole of the printed circuit board and cured, the surface thereof is generally convex. However, when an uncured resin layer, for example, an uncured solder resist layer after coating, drying, development and heat curing is previously laminated on a substrate, a hole resin composition is filled in a through hole and dried (precured) or cured in the main, or after the main curing is performed without a drying step, the composition is brought into contact with the uncured solder resist layer, and a part of the constituent components of the composition may diffuse and penetrate into the solder resist layer. As a result, the capacity of the resin composition for filling into the through-hole is reduced as a whole, the filling amount becomes insufficient, and after curing, a depression may be formed on the surface of the through-hole so as to be buried from the surface toward the inside of the through-hole.
This depression is one of the problems to be avoided, because it causes poor adhesion of plating in the subsequent plating step, poor adhesion in the further formation of a solder resist layer, and further prevents formation of a precise pattern.
In this regard, only by the technique of using the resin composition for filling holes described in
Therefore, based on the results of the studies by the present inventors, the following findings were obtained: the adjustment of the curing rate by the polyamine-type curing agent has a great influence on the occurrence of the depressions of the resin composition for pore filling after curing.
By increasing the curing speed with the polyamine-type curing agent, the penetration of the solution of the resin composition for via filling into the solder resist layer can be more effectively suppressed, and it is clear that the formation of the depression in the cured resin composition for via filling can be prevented.
From the above viewpoint, an object of the present invention is to provide a novel resin composition for pore filling, comprising: by using 2 kinds of epoxy resins in combination with a polyamine-type curing agent having a predetermined curing initiation temperature as a resin composition for via-filling of through-holes or via-holes, the curing speed can be increased, and thus even if the resin composition is cured in a state of being in contact with an uncured resin layer, for example, an uncured solder resist, it is possible to prevent a filling failure such as surface dishing from occurring.
Means for solving the problems
Namely, it was found that: the above problems can be solved by a curable resin composition for pore filling, comprising:
the curable resin composition for pore filling contains at least the following components (A) to (C):
(A) bisphenol E type epoxy resin,
(B) An epoxy resin having 3 or more functional groups, and
(C) a polyamine-type curing agent which is a polyamine-type curing agent,
and the curable resin composition for pore filling has a composition according to JIS-C2161: the gel time at 100 ℃ measured in 2010 is 30 minutes or less.
Among them, the polyamine-type curing agent (C) preferably has a curing initiation temperature of 95 ℃ or lower.
In another preferred embodiment, the curable resin composition for pore filling further contains an imidazole-type curing agent.
In a more preferred embodiment, the curable resin composition for pore filling further contains an inorganic filler.
Furthermore, in other preferred embodiments, the present invention further relates to: a cured product formed from the curable resin composition for filling holes, and an electronic component having the cured product.
In the present invention, (a) a bisphenol E type epoxy resin and (B) an epoxy resin having a 3-or more-functional group are used as main components of a curable resin composition for pore filling (hereinafter, also simply referred to as a curable resin composition), and (C) a polyamine type curing agent is used as a curing agent. Further, the structure is as follows: the curable resin composition of the present invention is prepared according to JIS-C2161: the gel time at 100 ℃ measured in 2010 is 30 minutes or less.
When the curable resin composition of the present invention having the above-described configuration is filled in a through hole or a via hole, even if the composition is in contact with an uncured resin layer such as an uncured solder resist, it is possible to suppress the occurrence of a filling failure in which a depression is generated on the surface of the composition after curing.
This is also related to the adjustment of the curing rate of the curable resin composition of the present invention by the polyamine-type curing agent. The details of the curable resin composition having the constitution of the present invention are described later in examples, but it was confirmed that the gel time is shorter, that is, the curing speed is faster, than the curable resin composition having the constitution other than these. This composition forms a cured product quickly after filling, and therefore it is considered that the component can be effectively inhibited from penetrating or diffusing into other uncured resin layers, for example, an uncured solder resist layer or the like, at the time of filling.
The respective components of the curable resin composition of the present invention will be described below.
[ (A) bisphenol E type epoxy resin ]
Resin compositions used for filling holes such as through holes in printed circuit boards are generally used as liquid resin compositions (filling inks), and therefore, in order to form a paste without a solvent, liquid epoxy resins, particularly, filling materials after curing, have excellent mechanical properties, electrical properties, and chemical properties, and good adhesion properties, and therefore, thermosetting epoxy resin compositions are widely used.
Among them, bisphenol E type epoxy resins are used in the present invention because of their low viscosity and high heat resistance, and are more suitable as resins for pore-filling applications.
As the bisphenol E epoxy resin, for example, EPOXMKR710 or R1710 (manufactured by AIR WATER INC) can be used. They are not easily crystallized and have good storage stability, and therefore, are suitable materials.
The content of the bisphenol E-type epoxy resin (a) is 1 to 40%, preferably 5 to 30%, based on the total mass of the curable resin composition.
[ (B) 3-functional or higher epoxy resin ]
The (B)3 or more functional epoxy resin used in the present invention is also understood to be a resin having 3 or more epoxy groups in 1 molecule.
In the present invention, the epoxy resin (B) having 3 or more functional groups is also used in combination, whereby more rapid curing can be achieved.
Examples of the (B) epoxy resin having 3 or more functions include a phenol novolac type epoxy resin, an alkylphenol novolac type epoxy resin, a liquid aminophenol type epoxy resin (particularly, a triglycidyl aminophenol type epoxy resin), a naphthalene type epoxy resin, a dicyclopentadiene type epoxy resin, a glycidyl amine type epoxy resin, a trishydroxyphenylmethane type epoxy resin, a tetrahydroxyphenylethane type epoxy resin, a diglycidyl phthalate resin, an alicyclic epoxy resin, and an alcohol ether type epoxy resin. Specific examples of the 3-or more-functional epoxy resin (B) include ADEKARESINEP-3980S (manufactured by ADEKA K.K.), ADEKA RESINEP-3950S (manufactured by ADEKA K.K.), and Jer-630 (manufactured by Mitsubishi chemical corporation).
Among them, liquid aminophenol type epoxy resins are preferable, and triglycidyl aminophenol type epoxy resins are particularly preferable.
The content of the (B) 3-or more-functional epoxy resin is 3 to 30%, preferably 5 to 20%, based on the total mass of the curable resin composition.
[ (C) polyamine-type curing agent ]
In the present invention, a polyamine-type curing agent is used as the curing agent, and examples thereof include modified aliphatic polyamines and modified aromatic polyamines.
Examples of the modified aliphatic polyamine include modified polyamines of ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, and pentaethylenehexamine.
Examples of the modified aromatic polyamine include modified polyamines of phenylenediamine and xylylenediamine.
Among them, from the viewpoint of faster curing speed, it preferably has a curing start temperature of 95 ℃ or lower, and more preferably has a curing start temperature of 80 ℃ or lower.
Specific examples of the polyamine-type curing agent (C) include FUJICURE FXR-1020 (manufactured by KOKAI T & K TOKA), and FUJICURE FXR-1081 (manufactured by KOKAI T & K TOKA).
In the present invention, (C) the polyamine-type curing agent may be used alone or in combination of 2 or more.
The content of the polyamine-type curing agent (C) is preferably adjusted so that the curing agent can be sufficiently cured by reacting with the bisphenol E-type epoxy resin (a) and the epoxy resin (B) having 3 or more functional groups.
The content thereof is 0.5 to 30% by mass, preferably 1 to 20% by mass, based on the total mass of the (a) bisphenol E type epoxy resin, (B)3 or more functional epoxy resin, and, when included, other epoxy resin in the curable resin composition of the present invention. When the content is in the range of 0.5 to 30% by mass, the curable resin composition is excellent in curability at low temperature and also good in storage stability.
[ imidazole type curing agent ]
In the present invention, in addition to the polyamine-type curing agent (C), an imidazole-type curing agent which has been conventionally used may be used in combination. In the above case, the heat resistance of a cured product formed from the curable resin composition is further improved, and therefore, it is preferable.
The gelation time was controlled to be fast by the imidazole type curing agent having a low curing initiation temperature, and the effect of preventing the occurrence of dishing when the polyamine type curing agent was used could not be obtained.
Examples of the imidazole-type curing agent include isocyanuric acid adducts of 2-methylimidazole, 2-ethyl-4-methylimidazole, 1, 2-dimethylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, and 2, 4-diamino-6- [2 '-methylimidazolyl- (1') ] -ethyl-s-triazine (isocyanuric acid is added to N at the 1-position of imidazole).
Further, examples of commercially available products thereof include 2MZ, 2MZ-P, 2PZ-PW, 2P4MZ, C11Z-CNS, 2PZ-CNS, 2PZCNS-PW, 2MZ-A, 2MZA-PW, C11Z-A, 2E4MZ-A, 2MA-OK, 2MAOK-PW, 2PZ-OK, 2MZ-OK, 2PHZ-PW, 2P4MHZ-PW, 2E4 MZ. BIS, VT-OK, MAVT-OK and MAVT-OK (manufactured by Kagaku Kogyo Co., Ltd.).
These imidazole-type curing agents may be used in combination of 2 or more.
The content of the imidazole-type curing agent is 0.5 to 12% by mass, preferably 1 to 10% by mass, based on the total mass of the bisphenol E-type epoxy resin (a), the epoxy resin having 3 or more functional groups (B), and the other epoxy resins when included in the curable resin composition of the present invention.
[ inorganic Filler ]
The curable resin composition of the present invention may further contain an inorganic filler used in a general resin composition.
Specific examples thereof include non-metal fillers such as silica, barium sulfate, calcium carbonate, silicon nitride, aluminum nitride, boron nitride, alumina, magnesium oxide, aluminum hydroxide, magnesium hydroxide, titanium oxide, mica, talc, nauburg silica (Neuburg silica), and organobentonite, and metal fillers such as copper, gold, silver, palladium, and silicon.
In the curable resin composition of the present invention, these inorganic fillers may be used alone or 2 or more kinds may be used in combination.
Among them, silica having low volume expansion and excellent printability and calcium carbonate having low volume expansion and excellent grindability are suitable.
The silica may be amorphous, crystalline, or a mixture thereof. Amorphous (fused) silica is particularly preferred. The calcium carbonate may be natural ground calcium carbonate or synthetic precipitated calcium carbonate. Particularly suitable is calcium carbonate having excellent grindability.
Examples of the shape of such an inorganic filler include a spherical shape, a needle shape, a plate shape, a scaly shape, a hollow shape, an indefinite shape, a hexagonal shape, a cubic shape, a flaky shape, and the like.
The average particle diameter of these inorganic fillers is preferably 0.1 to 25 μm. When the average particle diameter is 0.1 μm or more, the specific surface area is small, the filler is well dispersed due to the effect of aggregation of the fillers, and the filler loading amount is easily increased. On the other hand, if the thickness is 25 μm or less, the filling property into the through hole becomes good, and there is an effect that the smoothness becomes good when the conductive layer is formed in the hole-filled portion. More preferably 1 to 10 μm.
The average particle size refers to an average primary particle size. The average particle diameter (D50) can be measured by a laser diffraction/scattering method.
The content of these inorganic fillers is 300% or less, preferably 250% or less, based on the total mass of the (a) bisphenol E type epoxy resin, (B) 3-functional or more epoxy resin, and, when included, other epoxy resin in the curable resin composition of the present invention. If the content is 300% or less, the curable resin composition can be easily formed into a liquid paste, and good printability and pore-filling property can be obtained, and a cured product exhibits sufficiently low volume swelling property and also exhibits good polishing property.
[ other ingredients ]
The curable resin composition of the present invention may contain other components than the above components, depending on the desired properties.
Examples of such components include known and commonly used additives such as borate compounds, hydroquinone monomethyl ether, t-butylcatechol, pyrogallol, phenothiazine, and other known and commonly used thermal polymerization inhibitors, clay, kaolin, organobentonite, montmorillonite and other known and commonly used thickeners or thixotropic agents, silicone-based, fluorine-based, polymer-based defoaming agents and/or leveling agents, imidazole-based, thiazole-based, triazole-based, silane-coupling agents, and other adhesion-imparting agents.
[ cured product ]
The curable resin composition of the present invention can be easily filled into holes such as via holes and through holes of a printed circuit board by a conventionally employed method, for example, screen printing, roll coating, die coating, and the like. At this time, the filling is completely filled in a convex shape as if it slightly overflows from the hole. Next, the printed wiring board having the hole portion filled with the curable resin composition of the present invention is dried (precured) at, for example, 70 to 110 ℃ for about 10 to 120 minutes, and heated (main cured) at about 120 to 180 ℃ for about 10 to 180 minutes to cure the curable resin composition, thereby forming a cured product.
After curing the curable resin composition of the present invention as described above, unnecessary portions of the cured product that have overflowed from the surface of the printed wiring board can be removed by a known physical polishing method, and planarization can be achieved. Then, the wiring layer on the surface is patterned into a predetermined pattern, whereby a predetermined circuit pattern can be formed. If necessary, after roughening the surface of the cured product with an aqueous potassium permanganate solution or the like, a wiring layer can be formed on the cured product by electroless plating or the like.
[ electronic component ]
The present invention also provides an electronic component having the cured product.
By using the curable resin composition of the present invention, an electronic component with high quality, durability, and reliability maintained is provided.
The electronic component of the present invention is a component used in an electronic circuit, and further includes: active components such as printed circuit boards, transistors, light emitting diodes, laser diodes, and passive components such as resistors, capacitors, inductors, and connectors.
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, there is provided a curable resin composition for via filling of a through hole in a printed circuit board, comprising: even if other resin layers such as solder resist layers exist, the composition does not cause poor filling and does not cause surface depression after curing. Therefore, there is little concern about adverse effects on the formation of a precise pattern due to such a defect of filling the through hole.
Drawings
Fig. 1 is a sectional view schematically showing a state in which a through hole of a printed circuit board is filled with a curable resin composition for hole filling.
Fig. 2 is a sectional view schematically showing a state in which a through hole of a printed circuit board is filled with the curable resin composition for hole filling of the present invention and cured.
Fig. 3 is a cross-sectional view schematically showing a state in which a conventional curable resin composition for hole filling is filled in a through hole of a printed circuit board and cured.
Description of the reference numerals
1 printed
Detailed Description
The present invention will be specifically described below by way of examples and comparative examples, but the present invention is not limited to the following examples.
Unless otherwise specified, "part(s)" and "%" are based on mass.