U.S. patent application number 15/133838 was filed with the patent office on 2016-08-11 for thermosetting resin composition, method for producing resin composition varnish, prepreg and laminate.
The applicant listed for this patent is Hitachi Chemical Company, Ltd.. Invention is credited to Masahiro Aoshima, Hiroyuki Izumi, Yasuo Kamigata, Tomohiko Kotake, Masato Miyatake, Hikari Murai, Yoshihiro Takahashi, Shinji Tsuchikawa.
Application Number | 20160230037 15/133838 |
Document ID | / |
Family ID | 44195864 |
Filed Date | 2016-08-11 |
United States Patent
Application |
20160230037 |
Kind Code |
A1 |
Takahashi; Yoshihiro ; et
al. |
August 11, 2016 |
THERMOSETTING RESIN COMPOSITION, METHOD FOR PRODUCING RESIN
COMPOSITION VARNISH, PREPREG AND LAMINATE
Abstract
Discloses are a thermosetting resin composition containing a
maleimide compound including an unsaturated maleimide compound
having a specified chemical structure, a thermosetting resin, an
inorganic filler, and a molybdenum compound; a laminate plate for
wiring boards obtained by coating a base material with a
thermosetting resin composition containing a thermosetting resin,
silica, and a specified molybdenum compound and then performing
semi-curing to form a prepreg, and laminating and molding the
prepreg; and a method for manufacturing a resin composition varnish
including specified steps. According to the present invention,
electronic components having low thermal expansion properties and
excellent drilling processability and heat resistance, for example,
a prepreg, a laminate plate, an interposer, etc., can be
provided.
Inventors: |
Takahashi; Yoshihiro;
(Ibaraki, JP) ; Kamigata; Yasuo; (Ibaraki, JP)
; Murai; Hikari; (Ibaraki, JP) ; Aoshima;
Masahiro; (Ibaraki, JP) ; Tsuchikawa; Shinji;
(Ibaraki, JP) ; Miyatake; Masato; (Ibaraki,
JP) ; Kotake; Tomohiko; (Ibaraki, JP) ; Izumi;
Hiroyuki; (Ibaraki, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hitachi Chemical Company, Ltd. |
Tokyo |
|
JP |
|
|
Family ID: |
44195864 |
Appl. No.: |
15/133838 |
Filed: |
April 20, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13518578 |
Jun 22, 2012 |
|
|
|
PCT/JP2010/073376 |
Dec 24, 2010 |
|
|
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15133838 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08J 2300/24 20130101;
H05K 1/0306 20130101; C09D 7/63 20180101; B32B 15/08 20130101; C08K
13/02 20130101; C09D 7/61 20180101; Y10T 428/31529 20150401; C08K
2003/2206 20130101; C08K 2003/2227 20130101; H05K 1/0373 20130101;
C08K 2003/2296 20130101; C08J 2363/00 20130101; C08K 3/22 20130101;
C08K 2003/2255 20130101; Y10T 156/10 20150115; C08K 3/34 20130101;
C08K 3/36 20130101; C08K 5/3415 20130101; B32B 27/04 20130101; Y10T
428/31678 20150401; C09D 163/04 20130101; H05K 2201/0129 20130101;
H05K 2201/0209 20130101; H05K 3/0047 20130101; B32B 27/18 20130101;
C08L 63/00 20130101; H05K 1/0366 20130101; C09D 163/00 20130101;
C08K 3/013 20180101; C08J 5/24 20130101; C08K 5/3415 20130101; C08L
63/00 20130101 |
International
Class: |
C09D 163/04 20060101
C09D163/04; C08K 5/3415 20060101 C08K005/3415; C09D 7/12 20060101
C09D007/12; C08K 3/22 20060101 C08K003/22; C08K 3/34 20060101
C08K003/34; C08K 13/02 20060101 C08K013/02; C09D 163/00 20060101
C09D163/00; C08K 3/36 20060101 C08K003/36 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 25, 2009 |
JP |
2009-296058 |
Jul 15, 2010 |
JP |
2010-160979 |
Jul 23, 2010 |
JP |
2010-165556 |
Claims
1. A laminate plate for wiring boards, obtained by coating a
thermosetting resin composition containing (E) a thermosetting
resin (excluding a pre-reacted epoxy resin obtained by a
preliminary reaction of a phosphorus compound, a bifunctional epoxy
resin and a polyfunctional epoxy resin, or a preliminary reaction
of a phosphorus compound and a bifunctional epoxy resin), (F)
silica, and (G) at least one molybdenum compound selected from
calcium molybdate, and magnesium molybdate, with a content of the
silica (F) being 20% by volume or more and not more than 60% by
volume, on a base material in a film form or fiber form, then
performing semi-curing to form a prepreg, and laminating and
molding the prepreg.
2. The laminate plate for wiring boards according to claim 1,
wherein the silica (F) is fused spherical silica having an average
particle size of 0.1 .mu.m or more and not more than 1 .mu.m, and a
content of the molybdenum compound (G) is from 0.1% by volume or
more and not more than 10% by volume of the whole of the resin
composition.
3. The laminate plate for wiring boards according to claim 1,
obtained by coating the thermosetting resin composition after being
varnished.
4. The laminate plate for wiring boards according to claim 2,
obtained by coating the thermosetting resin composition after being
varnished.
5. The laminate plate for wiring boards according to claim 1,
wherein the base material in a film form or fiber form is a glass
cloth.
6. The laminate plate for wiring boards according to claim 2,
wherein the base material in a film form or fiber form is a glass
cloth.
7. The laminate plate for wiring boards according to claim 3,
wherein the base material in a film form or fiber form is a glass
cloth.
8. The laminate plate for wiring boards according to claim 4,
wherein the base material in a film form or fiber form is a glass
cloth.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a U.S. Divisional application of U.S. application
Ser. No. 13/518,578 filed Jun. 22, 2012, which is a U.S. national
phase application filed under 35 U.S.C. .sctn.371 of International
Application No. PCT/JP2010/073376, filed Dec. 24, 2010, designating
the United States, which claims priority from Japanese Patent
Applications 2010-165556 filed Jul. 23, 2010, 2010-160979 filed
Jul. 15, 2010, and 2009-296058 filed Dec. 25, 2009, the contents of
each of which are hereby incorporated herein by reference in their
entirety for all purposes.
TECHNICAL FIELD
[0002] The present invention relates to a thermosetting resin
composition which is especially low in thermal expansion properties
and excellent in drilling processability and heat resistance and
which is suitably used for electronic components, etc.; a prepreg
and a laminate plate each using the same; a laminate plate for
wiring boards requiring a drilling processing treatment at a
manufacturing stage for wiring board; a manufacturing method of a
resin composition varnish; and a prepreg and a laminate plate
fabricated utilizing the subject manufacturing method, each of
which is suitable for semiconductor packages and printed wiring
boards.
BACKGROUND ART
[0003] In a wiring board to be used for semiconductor packages
(hereinafter referred to as "interposer"), it is general to perform
a large number of drilling processing for interlayer connection of
wirings. In consequence, a laminate plate for interposers is
required to have high drilling processability.
[0004] Now, for a laminate plate for semiconductor packages, there
have hitherto been used a lot of curable resin compositions
composed of a bismaleimide compound and a cyanate resin (for
example, Patent Document 1). This is because in view of the fact
that the subject resin compositions are excellent in heat
resistance, the resin compositions were suitable as a resin
composition for the laminate plate for semiconductor packages,
which is frequently exposed to high temperatures in a reflow step
or the like at the time of mounting.
[0005] However, in recent years, requirements for thinning and
weight reduction of electronic appliances are increased, and
associated with rapid progress of thinning and high density of
semiconductor packages, laminate plates for semiconductor packages
have also been required to have higher characteristics other than
heat resistance over broad regions.
[0006] Above all, in order to suppress an increase of a warp at the
time of mounting to be caused due to thinning of a semiconductor
package, it is strongly required to make a coefficient of thermal
expansion of a laminate plate for semiconductor packages close to
that of a silicon chip, namely to realize low thermal
expansion.
[0007] While there are considered a variety of techniques for
realizing low thermal expansion of the laminate plate, it is
effective to allow a resin per se for laminate plates to realize
low thermal expansion, or to fill an inorganic filler in a high
density in a resin composition. For that reason, a novolak type
cyanate resin is used, or a content of the inorganic filler is
increased (for example, Patent Document 2).
[0008] But, the use of a cyanate resin or the filling of an
inorganic filler in a high density involved such a problem that
cutting properties of the resin composition are lowered, thereby
significantly impairing drilling processability of a laminate plate
using such a resin composition.
[0009] Then, there was made an attempt to prevent a lowering of the
drilling processability by adding a plate-shaped filler such as
burnt talc, etc. as an inorganic filler or reducing a content the
inorganic filler (for example, Patent Document 3). However, there
were such inconveniences that the effect for preventing a lowering
of the drilling processability is insufficient; the resin
composition becomes low in elasticity, so that the effect for
suppressing a warp of the semiconductor package is insufficient;
and so on. Thus, satisfactory results have not been obtained
yet.
[0010] In order to realize low thermal expansion of the laminate
plate, it is effective to increase a content of a filler having a
small coefficient of thermal expansion, such as silica, among
inorganic fillers in the resin composition used in the laminate
plate. But, if the content of a hard filler such as silica is
increased, there was encountered such a problem that the drilling
processability of the laminate plate is lowered.
[0011] Also, in order to enhance the drilling processability, there
is made an attempt to add a metal dichalcogenide such as molybdenum
disulfide as an inorganic solid lubricant particle (see, for
example, Patent Document 4). But, if molybdenum disulfide is added,
there is encountered such a problem that electrical insulating
properties of the laminate plate are significantly lowered. Thus,
satisfactory results have not been obtained yet.
[0012] Then, in order to solve this problem, the present inventors
investigated additives which even when an inorganic filler is
filled in high density, can inhibit the deterioration of the
drilling processability and then found that a molybdenum compound
has an excellent effect.
[0013] But, since the molybdenum compound has a large specific
gravity, when added directly to a resin composition varnish to be
used for the fabrication of a laminate plate, it easily
precipitates to cause defective manufacture. For that reason, it is
recommended to use a particle having a molybdenum compound
supported on talc or the like (for example, KEMIGARD 911C,
manufactured by Sherwin-Williams Company) (see, for example, Patent
Document 5). However, there are such drawbacks that the resin
composition varnish is thickened; aggregation of the molybdenum
compound-supported particles with each other easily occurs; and so
on. Thus, satisfactory results are not obtained.
PRIOR ART DOCUMENTS
Patent Documents
[0014] Patent Document 1: JP-A-3-52773
[0015] Patent Document 2: Japanese Patent No. 4132703
[0016] Patent Document 3: JP-A-2005-162787
[0017] Patent Document 4: JP-T-2002-527538
[0018] Patent Document 5: JP-A-2000-264986
DISCLOSURE OF THE INVENTION
[0019] Under such circumstances, the present invention has been
made. A first object of the present invention is to provide a
thermoplastic resin composition which is especially low in thermal
expansion properties and excellent in drilling processability and
heat resistance and which is suitably used for electronic
components, etc., and a prepreg and a laminate plate each using the
same; and a second object thereof is to provide a laminate plate
for wiring boards, which is very excellent in drilling
processability at the time of fabricating a wiring board and which
also has favorable electrical insulating properties and low thermal
expansion properties.
[0020] Furthermore, a third object of the present invention is to
provide a method for manufacturing a resin composition varnish, in
which precipitation or aggregation of a molybdenum compound hardly
occurs, and a prepreg and a laminate plate each having a low
coefficient of thermal expansion and high drilling
processability.
[0021] The present inventors made extensive and intensive
investigations. As a result, it has been found that the foregoing
first object can be achieved by a thermosetting resin composition
containing an unsaturated maleimide compound having an acidic
substituent composed of a specified chemical formula, a
thermosetting resin, an inorganic filler, and a molybdenum
compound; the foregoing second object can be achieved by forming a
laminate plate by using a thermosetting resin composition
containing a thermosetting resin, a specified amount of silica, and
a specified molybdenum compound; and furthermore, the foregoing
third object can be achieved by manufacturing a resin composition
varnish by a method in which after a molybdenum compound is
dispersed and mixed in a slurry having a specified silica particle
dispersed therein, this slurry is added to a varnish containing a
thermosetting resin, and thereafter, an inorganic filler is blended
therewith. The present invention has been accomplished on the basis
of such knowledge.
[0022] That is, the present invention provides the following.
(1) A thermosetting resin composition comprising (A) a maleimide
compound containing an unsaturated maleimide compound having an
acidic substituent, as represented by the following general formula
(I) or (II), (B) a thermosetting resin, (C) an inorganic filler,
and (D) a molybdenum compound:
##STR00001##
[0023] (In the formulae, R.sub.1 represents a hydroxyl group, a
carboxyl group, or a sulfonic acid group, each of which is the
acidic substituent; each of R.sub.2, R.sub.3, R.sub.4, and R.sub.5
independently represents a hydrogen atom, an aliphatic hydrocarbon
group having a carbon number of from 1 to 5, or a halogen atom; A
represents an alkylene group, an alkylidene group, an ether group,
a sulfonyl group, or a group represented by the following formula
(III); x represents an integer of from 1 to 5; y represents an
integer of from 0 to 4; and a sum of x and y is 5.)
##STR00002##
(2) The thermosetting resin composition as set forth above in (1),
wherein the molybdenum compound (D) is at least one member selected
from a molybdenum oxide and a molybdic acid compound, and a content
of the molybdenum compound is from 0.02 to 20% by volume of the
whole of the resin composition. (3) The thermosetting resin
composition as set forth above in (1) or (2), wherein the
thermosetting resin (B) is an epoxy resin; a total sum content of
the component (A) and the component (B) is from 30 to 80% by volume
of the whole of the resin composition; and a mass ratio of the
component (A) and the component (B) is from 20 to 90 parts by mass
in terms of the component (A) based on 100 parts by mass of the
total sum content of the component (A) and the component (B). (4)
The thermosetting resin composition as set forth above in any one
of (1) to (3), wherein the inorganic filler (C) is fused spherical
silica, and a content of the inorganic filler is from 10 to 60% by
volume of the whole of the resin composition. (5) A prepreg
obtained by impregnating or coating a base material with the
thermosetting resin composition asset forth above in any one of (1)
to (4) and then performing B-staging. (6) A laminate plate obtained
by laminating and molding the prepreg as set forth above in (5).
(7) The laminate plate as set forth above in (6), which is a metal
clad laminate plate obtained by superimposing a metal foil on at
least one surface of the prepreg and then performing heat pressure
molding. (8) A laminate plate for wiring boards, obtained by
coating a thermosetting resin composition containing (E) a
thermosetting resin, (F) silica, and (G) at least one molybdenum
compound selected from zinc molybdate, calcium molybdate, and
magnesium molybdate, with a content of the silica (F) being 20% by
volume or more and not more than 60% by volume, on a base material
in a film form or fiber form, then performing semi-curing to form a
prepreg, and laminating and molding the prepreg. (9) The laminate
plate for wiring boards as set forth above in (8), wherein the
silica (F) is fused spherical silica having an average particle
size of 0.1 .mu.m or more and not more than 1 .mu.m, and a content
of the molybdenum compound (G) is from 0.1% by volume or more and
not more than 10% by volume of the whole of the resin composition.
(10) The laminate plate for wiring boards as set forth above in (8)
or (9), wherein the thermosetting resin composition is varnished.
(11) The laminate plate for wiring boards as set forth above in any
one of (8) to (10), wherein the base material in a film form or
fiber form is a glass cloth. (12) A method for manufacturing a
resin composition varnish comprising
[0024] a first dispersing and mixing step of dispersing and mixing
(I) a molybdenum compound in (H) a slurry containing a silica
particle having an average particle size of 0.01 .mu.m or more and
not more than 0.1 .mu.m and a specific surface area of 30 m.sup.2/g
or more and not more than 270 m.sup.2/g,
[0025] a second dispersing and mixing step of dispersing and mixing
the slurry having gone through the first dispersing and mixing step
in a varnish containing (J) a thermosetting resin, and
[0026] a third dispersing and mixing step of dispersing and mixing
(K) an inorganic filler exclusive of the silica particle and the
molybdenum compound in the varnish having gone through the second
dispersing and mixing step.
(13) The method for manufacturing a resin composition varnish as
set forth above in (12), further comprising a curing accelerator
adding step of adding a curing accelerator to the varnish after the
third dispersing and mixing step. (14) The method for manufacturing
a resin composition varnish as set forth above in (12) or (13),
wherein the molybdenum compound (I) is one member or a mixture of
two or more members selected from the group consisting of zinc
molybdate, calcium molybdate, and magnesium molybdate. (15) A
prepreg comprising a base material impregnated and coated with a
resin composition varnish obtained through a first dispersing and
mixing step of dispersing and mixing (I) a molybdenum compound in
(H) a slurry containing a silica particle having an average
particle size of 0.01 .mu.m or more and not more than 0.1 .mu.m and
a specific surface area of 30 m.sup.2/g or more and not more than
270 m.sup.2/g; a second dispersing and mixing step of dispersing
and mixing the slurry having gone through the first dispersing and
mixing step in a varnish containing (J) a thermosetting resin; and
a third dispersing and mixing step of dispersing and mixing (K) an
inorganic filler in the varnish having gone through the second
dispersing and mixing step. (16) A laminate plate obtained by
laminating and molding the prepreg as set forth above in (15).
[0027] The thermosetting resin composition of the present invention
is especially low in thermal expansion properties and excellent in
drilling processability and heat resistance and is suitably used
for electronic components, etc.
[0028] For that reason, according to the present invention, a
prepreg and a laminate plate each having an excellent performance,
and so on can be provided by using the subject thermosetting resin
composition.
[0029] Also, according to the present invention, a laminate plate
for wiring boards, which is very excellent in drilling
processability at the time of fabricating a wiring board and which
also has favorable electrical insulating properties and low thermal
expansion properties, can be provided. In consequence, when an
interposer is manufactured by using the laminate plate for wiring
boards of the present invention, a semi-conductor package which is
less in a warp at low costs can be obtained.
[0030] Furthermore, according to the present invention, a method
for manufacturing a resin composition varnish, in which
precipitation or aggregation of a molybdenum compound hardly
occurs, and a prepreg and a laminate plate each having a low
coefficient of thermal expansion and high drilling processability
can be provided.
MODES FOR CARRYING OUT THE INVENTION
[0031] First of all, the thermosetting resin composition of the
present invention is described.
[Thermosetting Resin Composition]
[0032] The thermosetting resin composition of the present invention
is a resin composition containing, as essential components, (A) a
maleimide compound containing an unsaturated maleimide compound
having an acidic substituent, as represented by the following
general formula (I) or (II), (B) a thermosetting resin, (C) an
inorganic filler, and (D) a molybdenum compound.
##STR00003##
[0033] In the formulae, R.sub.1 represents a hydroxyl group, a
carboxyl group, or a sulfonic acid group, each of which is the
acidic substituent; each of R.sub.2, R.sub.3, R.sub.4, and R.sub.5
independently represents a hydrogen atom, an aliphatic hydrocarbon
group having a carbon number of from 1 to 5, or a halogen atom,
R.sub.2 to R.sub.5 may be the same as or different from each other;
A represents an alkylene group, an alkylidene group, an ether
group, a sulfonyl group, or a group represented by the following
formula (III); x represents an integer of from 1 to 5; y represents
an integer of from 0 to 4; and a sum of x and y is 5.
##STR00004##
[0034] First of all, the unsaturated maleimide compound having an
acidic substituent, as represented by the general formula (I) or
(II), which is the component (A), can be, for example, manufactured
by allowing a maleimide compound having at least two N-substituted
maleimide groups in one molecule thereof and an amine compound
having an acidic substituent represented by the following general
formula (IV) to react with each other in an organic solvent.
##STR00005##
[0035] In the formula, each R.sub.1 independently represents a
hydroxyl group, a carboxyl group, or a sulfonic acid group, which
is the acidic substituent; each R.sub.2 independently represents a
hydrogen atom, an aliphatic hydrocarbon group having a carbon
number of from 1 to 5, or a halogen atom; x represents an integer
of from 1 to 5; y represents an integer of from 0 to 4; and a sum
of x and y is 5.
[0036] Examples of the maleimide compound having at least two
N-substituted maleimide groups in one molecule thereof include
bis(4-maleimidophenyl)methane, bis(4-maleimidophenyl)ether,
bis(4-maleimidophenyl)sulfone,
3,3-dimethyl-5,5-diethyl-4,4-diphenylmethane bismaleimide,
4-methyl-1,3-phenylene bismaleimide, m-phenylene bismaleimide,
2,2-bis-(4-(4-maleimidophenoxy)phenyl)propane, and so on.
[0037] Of these, bis(4-maleimidophenyl)methane, m-phenylene
bismaleimide, and bis(4-maleimidophenyl)sulfone are preferable
because these compounds have high reactivity and are able to
realize higher heat resistance; m-phenylene bismaleimide and
bis(4-maleimidophenyl)methane are more preferable from the
standpoint of inexpensiveness; and bis(4-maleimidephenyl)methane is
especially preferable from the standpoint of solubility in a
solvent.
[0038] Examples of the amine compound having an acidic substituent
represented by the general formula (IV) include m-aminophenol,
p-aminophenol, o-aminophenol, p-aminobenzoic acid, m-aminobenzoic
acid, o-aminobenzoic acid, o-aminobenzenesulfonic acid,
m-aminobenzenesulfonic acid, p-aminobenzenesulfonic acid,
3,5-dihydroxyaniline, 3,5-dicarboxyaniline, and so on. Of these,
m-aminophenol, p-aminophenol, p-aminobenzoic acid, m-aminobenzoic
acid, and 3,5-dihydroxyaniline are preferable from the standpoints
of solubility and synthetic yield; and m-aminophenol and
p-aminophenol are more preferable from the standpoint of heat
resistance.
[0039] Though the organic solvent which is used for this reaction
is not particularly limited, examples thereof include an alcohol
based solvent such as ethanol, propanol, butanol, methyl
cellosolve, butyl cellosolve, propylene glycol monomethyl ether,
etc.; a ketone based solvent such as acetone, methyl ethyl ketone,
methyl isobutyl ketone, cyclohexanone, etc.; an ether based solvent
such as tetrahydrofuran, etc.; an aromatic solvent such as toluene,
xylene, mesitylene, etc.; a nitrogen atom-containing solvent such
as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.;
a sulfur atom-containing solvent such as dimethyl sulfoxide, etc.;
and so on. These can be used singly or in admixture of two or more
kinds thereof.
[0040] Of these organic solvents, cyclohexanone, propylene glycol
monomethyl ether, and methyl cellosolve are preferable from the
standpoint of solubility; cyclohexanone and propylene glycol
monomethyl ether are more preferable from the standpoint of low
toxicity; and propylene glycol monomethyl ether is especially
preferable in view of the fact that it is high in the volatility
and hardly remains as a residual solvent at the time of
manufacturing a prepreg.
[0041] A use amount of the organic solvent is preferably from 10 to
1,000 parts by mass, more preferably from 100 to 500 parts by mass,
and especially preferably from 200 to 500 parts by mass based on
100 parts by mass of a total sum of the maleimide compound having
at least two N-substituted maleimide groups in one molecule thereof
and the amine compound having an acidic substituent represented by
the general formula (IV).
[0042] When the use amount of the organic solvent is 10 parts by
mass or more, the solubility is sufficient, whereas when it is not
more than 1,000 parts by mass, the reaction time is not excessively
long.
[0043] As for use amounts of the maleimide compound having at least
two N-substituted maleimide groups in one molecule thereof and the
amine compound having an acidic substituent represented by the
general formula (IV), an equivalent ratio of a maleimide group
equivalent of the maleimide compound and an equivalent of the amine
compound as reduced into an --NH.sub.2 group is preferably in the
range represented by the following expression.
1.0<(Maleimide group equivalent)/(Equivalent as reduced into an
--NH.sub.2 group).ltoreq.10.0
[0044] The subject equivalent ratio is more preferably in the range
of from 2.0 to 10.0. By allowing the subject equivalent ratio to
fall within the foregoing range, the solubility in a solvent does
not become insufficient, the gelation is not caused, and the heat
resistance of the thermosetting resin is not lowered.
[0045] Also, preferably, a reaction temperature is in the range of
from 50 to 200.degree. C., and a reaction time is in the range of
from 0.1 to 10 hours; and more preferably, the reaction temperature
is in the range of from 100 to 160.degree. C., and the reaction
time is in the range of from 1 to 8 hours.
[0046] Incidentally, a reaction accelerator can be used in this
reaction, as the need arises. Examples of the reaction accelerator
include an amine such as triethylamine, pyridine, tributylamine,
etc.; an imidazole such as methyl imidazole, phenyl imidazole,
etc.; and an organic phosphorus based compound such as triphenyl
phosphine, etc. These can be used singly or in admixture of two or
more kinds thereof.
[0047] By allowing the thermosetting resin composition of the
present invention to contain the unsaturated maleimide compound
having an acidic substituent represented by the foregoing general
formula (I) or (II) as the component (A), low thermal expansion
properties and excellent heat resistance are revealed. Though the
component (A) may contain other maleimide compound, it is
preferable that the component (A) contains 60% by mass or more of
the unsaturated maleimide compound having an acidic substituent
represented by the general formula (I) or (II).
[0048] Examples of the thermosetting resin as the component (B)
include an epoxy resin, a phenol resin, an unsaturated imide resin,
a cyanate resin, an isocyanate resin, a benzoxazine resin, an
oxetane resin, an amino resin, an unsaturated polyester resin, an
allyl resin, a dicyclopentadiene resin, a silicone resin, a
triazine resin, a melamine resin, and so on. These can be used
singly or in admixture of two or more kinds thereof.
[0049] Of these, an epoxy resin is preferable from the standpoints
of moldability and electrical insulating properties. Examples of
such an epoxy resin include a bisphenol A type epoxy resin, a
bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a
phenol novolak type epoxy resin, a cresol novolak type epoxy resin,
a bisphenol A novolak type epoxy resin, a bisphenol F novolak type
epoxy resin, a biphenyl type epoxy resin, a xylylene type epoxy
resin, a biphenyl aralkyl type epoxy resin, a naphthalene type
epoxy resin, a dicyclopentadiene type epoxy resin, an alicyclic
epoxy resin, a diglycidyl ether compound of a polyfunctional phenol
or a polycyclic aromatic compound such as anthracene, etc., and so
on. These can be used singly or in admixture of two or more kinds
thereof.
[0050] In the case of using an epoxy resin as the thermosetting
resin, a curing agent or a curing accelerator of the epoxy resin
can be used, as the need arises. Examples of the curing agent
include a polyfunctional phenol compound such as phenol novolak,
cresol novolak, etc.; an amine compound such as dicyandiamide,
diaminodiphenylmethane, diaminodiphenylsulfone, etc.; an acid
anhydride such as phthalic anhydride, pyromellitic anhydride,
maleic anhydride, a maleic anhydride copolymer, etc.; and so on.
These can be used singly or in admixture of two or more kinds
thereof.
[0051] Also, examples of the curing accelerator include an
imidazole and a derivative thereof, an organic phosphorus based
compound, a secondary amine, a tertiary amine, a quaternary
ammonium salt, and so on. These can be used singly or in admixture
of two or more kinds thereof.
[0052] As for contents of the component (A) and the component (B),
a total sum content of the component (A) and the component (B) is
preferably from 30 to 80% by volume, and more preferably from 40 to
70% by volume of the whole of the resin composition. By allowing
the total sum content of the component (A) and the component (B) to
fall within the range of from 30 to 80% by volume, the moldability
and low thermal expansion properties of the resin composition can
be kept favorable.
[0053] Also, a mass ratio of the component (A) and the component
(B) is preferably from 20 to 90 parts by mass, and more preferably
from 30 to 80 parts by mass in terms of the component (A) based on
100 parts by mass of the total sum content of the component (A) and
the component (B). By allowing the content of the component (A) to
fall within the range of from 20 to 90 parts by mass, the
incombustibility, adhesion, and heat resistance of the resin
composition can be kept favorable.
[0054] Examples of the inorganic filler as the component (C)
include silica, alumina, talc, mica, kaolin, aluminum hydroxide,
magnesium hydroxide, zinc borate, zinc stannate, zinc oxide,
titanium oxide, boron nitride, calcium carbonate, barium sulfate,
aluminum borate, potassium titanate, a glass powder of E-glass,
S-glass, D-glass, etc., a hollow glass bead, and so on. These can
be used singly or in admixture of two or more kinds thereof.
[0055] Of these, silica is preferable from the standpoint of low
thermal expansion properties. Examples of the silica include
precipitated silica which is manufactured by a wet process and
which has a high water content; and dry process silica which is
manufactured by a dry process and which does not substantially
contain bonding water, etc. Furthermore, the dry process silica
includes crushed silica, fumed silica, and fused spherical silica
depending upon a difference of the manufacturing method. Of these,
from the standpoints of low thermal expansion properties and high
fluidity upon being filled in the resin, fused spherical silica is
preferable.
[0056] In the case of using fused spherical silica as the inorganic
filler as the component (C), its average particle size is
preferably from 0.1 to 10 .mu.m, and more preferably from 0.3 to 8
.mu.m.
[0057] When the average particle size of the fused spherical silica
is controlled to 0.1 .mu.m or more, the fluidity at the time of
filling the fused spherical silica in a high density in the resin
composition can be kept favorable, whereas when it is controlled to
not more than 10 .mu.m, a probability of incorporation of coarse
particles is reduced, thereby enabling one to suppress the
generation of failure to be caused due to the coarse particles.
[0058] When a cumulative distribution curve by particle size is
determined while defining the whole volume of the particles as
100%, the average particle size as referred to herein means a
particle size corresponding to just 50% of the volume, and it can
be measured by a particle size distribution analyzer adopting a
laser diffraction scattering method, or the like.
[0059] A content of the inorganic filler as the component (C) is
preferably from 10 to 60% by volume, and more preferably from 20 to
50% by volume of the whole of the resin composition. By allowing
the content of the inorganic filler to fall within the range of
from 10 to 60% by volume of the whole of the resin composition, the
moldability and low thermal expansion properties of the resin
composition can be kept favorable.
[0060] Examples of the molybdenum compound as the component (D)
include a molybdenum oxide and a molybdic acid compound such as
molybdenum trioxide, zinc molybdate, ammonium molybdate, magnesium
molybdate, calcium molybdate, barium molybdate, sodium molybdate,
potassium molybdate, phosphomolybdic acid, ammonium
phosphomolybdate, sodium phosphomolybdate, silicomolybdic acid,
etc.; and an inorganic molybdenum compound such as molybdenum
boride, molybdenum disilicate, molybdenum nitride, molybdenum
carbide, etc. These can be used singly or in admixture of two or
more kinds thereof.
[0061] Of these, a molybdenum oxide and a molybdic acid compound
are preferable from the standpoint that the effect for preventing a
lowering of the drilling processability is favorable; and
furthermore, zinc molybdate, calcium molybdate, and magnesium
molybdate are especially preferable from the standpoints of low
water solubility and toxicity and high electrical insulating
properties.
[0062] In the case where zinc molybdate, calcium molybdate, or
magnesium molybdate is used as the component (D), by supporting
such a molybdenum compound on talc, silica, zinc oxide, calcium
carbonate, magnesium hydroxide, or the like and using it, it is
possible to contrive to prevent precipitation and enhance
dispersibility at the time of dissolving the resin composition in
an organic solvent to form a varnish. Examples of such a molybdenum
compound include KEMGARD 911C, manufactured by Sherwin-Williams
Company, which is one having zinc molybdate supported on talc.
[0063] A content of the molybdenum compound as the component (D) is
preferably from 0.02 to 20% by volume, and more preferably from 0.1
to 15% by volume of the whole of the resin composition. By allowing
the content of the molybdenum compound to fall within the range of
from 0.02 to 20% by volume of the whole of the resin composition,
not only the adhesion of the resin composition can be kept
favorable, but the effect for preventing a lowering of the drilling
processability can be sufficiently obtained.
[0064] Furthermore, the thermosetting resin composition of the
present invention can arbitrarily contain known thermoplastic
resin, elastomer, organic filler, flame retarder, ultraviolet ray
absorber, antioxidant, and adhesion enhancer, and the like to an
extent such that thermosetting properties as the resin composition
are not impaired.
[0065] Examples of the thermoplastic resin include polyethylene,
polypropylene, polystyrene, a polyphenylene ether resin, a phenoxy
resin, a polycarbonate resin, a polyester resin, a polyamide resin,
a polyamide-imide resin, a polyimide resin, a xylene resin, a
polyphenylene sulfide resin, a polyether imide resin, a
polyetheretherketone resin, a polyether imide resin, a silicone
resin, a tetrafluoroethylene resin, and so on.
[0066] Examples of the elastomer include polybutadiene,
polyacrylonitrile, epoxy-modified polybutadiene, maleic
anhydride-modified polybutadiene, phenol-modified polybutadiene,
carboxy-modified polyacrylonitrile, and so on.
[0067] Examples of the organic filler include a resin filler having
a homogeneous structure, which is composed of polyethylene,
polypropylene, polystyrene, a polyphenylene ether resin, a silicone
resin, a tetrafluoroethylene resin, or the like; a resin filler of
a core-shell structure having a core layer in a rubber state, which
is composed of an acrylic acid ester based resin, a methacrylic
acid ester based resin, a conjugated diene based resin, or the
like, and a shell layer in a vitreous state, which is composed of
an acrylic acid ester based resin, a methacrylic acid ester based
resin, an aromatic vinyl based resin, a vinyl cyanide based resin,
or the like; and so on.
[0068] Examples of the flame retarder include a halogen-containing
flame retarder containing bromine or chlorine; a phosphorus based
flame retarder such as triphenyl phosphate, tricresyl phosphate,
trisdichloropropyl phosphate, red phosphorus, etc.; a nitrogen
based flame retarder such as guanidine sulfamate, melamine sulfate,
melamine polyphosphate, melamine cyanurate, etc.; a phosphazene
based flame retarder such as cyclophosphazene, polyphosphazene,
etc.; an inorganic flame retarder such as antimony trioxide, etc.;
and so on.
[0069] Examples of the ultraviolet ray absorber include a
benzotriazole based ultraviolet ray absorber and so on.
[0070] Examples of the antioxidant include a hindered phenol based
or hindered amine based antioxidant. Examples of the adhesion
enhancer include a coupling agent such as a silane series, a
titanate series, an aluminate series, etc.; and so on.
[0071] The thermosetting resin composition of the present invention
is impregnated into or coated on a base material, subsequently
subjected to B-staging, and then used as a prepreg. At the time of
use for the prepreg, it is preferable to render the thermosetting
resin composition in a state of a varnish in which the respective
components are finally dissolved or dispersed in an organic
solvent.
[0072] Examples of the organic solvent which is used on that
occasion include an alcohol based solvent such as methanol,
ethanol, propanol, butanol, methyl cellosolve, butyl cellosolve,
propylene glycol monomethyl ether, etc.; a ketone based solvent
such as acetone, methyl ethyl ketone, methyl isobutyl ketone,
cyclohexanone, etc.; an ester based solvent such as butyl acetate,
propylene glycol monomethyl ether acetate, etc.; an ether based
solvent such as tetrahydrofuran, etc.; an aromatic solvent such as
toluene, xylene, mesitylene, etc.; a nitrogen atom-containing
solvent such as dimethylformamide, dimethylacetamide,
N-methylpyrrolidone, etc.; a sulfur atom-containing solvent such as
dimethyl sulfoxide, etc.; and so on. These can be used singly or in
admixture of two or more kinds thereof.
[0073] Of these, from the standpoint of solubility, methyl ethyl
ketone, methyl isobutyl ketone, cyclohexanone, methyl cellosolve,
and propylene glycol monomethyl ether are preferable; and from the
standpoint of low toxicity, methyl isobutyl ketone, cyclohexanone,
and propylene glycol monomethyl ether are more preferable.
[0074] Also, at the time of blending in the varnish, it is
preferable to subject the inorganic filler to a pre-treatment with
a surface treating agent such as a coupling agent, e.g., a silane
series, a titanate series, etc., a silicone oligomer, or the like,
or to an integral blend treatment.
[0075] A content of the resin composition in the finally obtained
varnish is preferably from 40 to 90% by mass, and more preferably
from 50 to 80% by mass of the whole of the varnish. By allowing the
content of the resin composition in the varnish to fall within the
range of from 40 to 90% by mass, the coating properties can be kept
favorable, and a prepreg having an appropriate attachment amount of
the resin composition can be obtained.
[0076] The prepreg of the present invention is one obtained by
impregnating or coating a base material with the thermosetting
resin composition of the present invention and then performing
B-staging. That is, the prepreg of the present invention is
manufactured by impregnating or coating a base material with the
thermosetting resin composition of the present invention and then
performing semi-curing (B-staging) by heating or the like. The
prepreg of the present invention is hereunder described in
detail.
[0077] For the base material which is used for the prepreg of the
present invention, well-known materials which are used for various
laminate plates for electrical insulating materials can be used.
Examples of the material include fibers of an inorganic material
such as E-glass, D-glass, S-glass, Q-glass, etc.; fibers of an
organic material such as aramid, polyester,
polytetrafluoroethylene, etc.; mixtures thereof; and so on.
[0078] Though such a base material has a form of, for example, a
woven fabric, a nonwoven fabric, a roving, a chopped strand mat, a
surfacing mat, etc., the material and the shape are selected
depending on an application or a performance of the target molded
article, and the material and the shape can be employed solely or
in combination of two or more kinds thereof, as the need
arises.
[0079] Though the base material is not particularly limited with
respect to its thickness, for example, those having a thickness of
from about 0.01 to 0.2 mm can be used. Those having been subjected
to a surface treatment with a silane coupling agent, etc., or those
having been subjected to a mechanical opening treatment are
suitable from the standpoints of heat resistance, moisture
resistance, and processability. The prepreg of the present
invention can be obtained by impregnating or coating the base
material with the resin composition in such a manner that an
attachment amount thereof relative to the base material is from 20
to 90% by mass in terms of a resin content of the prepreg after
drying, and then heating for drying usually at a temperature of
from 100 to 200.degree. C. for from 1 to 30 minutes to achieve
semi-curing (B-staging).
[0080] The laminate plate of the present invention is one obtained
by laminating and molding the prepreg of the present invention.
That is, the laminate plate is, for example, one obtained by
lamination and molding in a configuration in which from 1 to 20
sheets of the prepreg of the present invention are superimposed,
and a metal foil such as copper, aluminum, etc. is disposed on one
surface or both surfaces thereof. As for a molding condition, for
example, techniques for a laminate plate or multi-layered board for
electrical insulating materials can be applied. The molding can be
performed within the range at a temperature of from 100 to
250.degree. C. under a pressure of from 0.2 to 10 MPa for a heating
time of from 0.1 to 5 hours by using, for example, a multi-stage
press, a multi-stage vacuum press, a continuous molding machine, an
autoclave molding machine, etc. Also, a multi-layered board can be
manufactured by combining the prepreg of the present invention with
a wiring board for internal layer and laminating and molding the
combination.
[0081] Next, the laminate plate for wiring boards of the present
invention is described.
[Laminate Plate for Wiring Boards]
[0082] The laminate plate for wiring boards of the present
invention is one obtained by coating a thermosetting resin
composition containing (E) a thermosetting resin, (F) silica, and
(G) at least one molybdenum compound selected from zinc molybdate,
calcium molybdate, and magnesium molybdate, with a content of the
silica (F) being 20% by volume or more and not more than 60% by
volume, on a base material in a film form or fiber form and then
performing semi-curing to forma prepreg, and laminating and molding
the prepreg.
[0083] Of these, examples of the thermosetting resin as the
component (E) include an epoxy resin, a phenol resin, an
unsaturated imide resin, a cyanate resin, an isocyanate resin, a
benzoxazine resin, an oxetane resin, an amino resin, an unsaturated
polyester resin, an allyl resin, a dicyclopentadiene resin, a
silicone resin, a triazine resin, a melamine resin, and so on.
These can be used singly or in admixture of two or more kinds
thereof.
[0084] Of these, from the standpoints of moldability and electrical
insulating properties, it is preferable to use the epoxy resin
alone or in admixture.
[0085] Examples of the epoxy resin which is used include a
bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a
bisphenol S type epoxy resin, a phenol novolak type epoxy resin, a
cresol novolak type epoxy resin, a bisphenol A novolak type epoxy
resin, a bisphenol F novolak type epoxy resin, a biphenyl type
epoxy resin, a xylylene type epoxy resin, a biphenyl aralkyl type
epoxy resin, a naphthalene type epoxy resin, a dicyclopentadiene
type epoxy resin, an alicyclic epoxy resin, a diglycidyl ether
compound of a polyfunctional phenol or a polycyclic aromatic
compound such as anthracene, etc., and so on. These can be used
singly or in admixture of two or more kinds thereof.
[0086] In the case of using an epoxy resin as the thermosetting
resin, a curing agent or a curing accelerator of the epoxy resin
can be used, as the need arises.
[0087] Examples of the curing agent include a polyfunctional phenol
compound such as phenol novolak, cresol novolak, etc.; an amine
compound such as dicyandiamide, diaminodiphenylmethane,
diaminodiphenylsulfone, etc.; an acid anhydride such as phthalic
anhydride, pyromellitic anhydride, maleic anhydride, a maleic
anhydride copolymer, etc.; and so on. These can be used singly or
in admixture of two or more kinds thereof.
[0088] Also, examples of the curing accelerator include an
imidazole and a derivative thereof, an organic phosphorus based
compound, a secondary amine, a tertiary amine, a quaternary
ammonium salt, and so on. These can be used singly or in admixture
of two or more kinds thereof.
[0089] Examples of the silica as the component (F) include
precipitated silica which is manufactured by a wet process and
which has a high water content; and dry process silica which is
manufactured by a dry process and which does not substantially
contain bonding water, etc. The dry process silica includes crushed
silica, fumed silica, and fused spherical silica depending upon a
difference of the manufacturing method. Of these, from the
standpoints of low thermal expansion properties and high fluidity
upon being blended in the resin, fused spherical silica is
preferable.
[0090] In the case of using fused spherical silica as the silica,
its average particle size is preferably from 0.1 .mu.m or more and
not more than 1 .mu.m. When the average particle size of the fused
spherical silica is controlled to 0.1 .mu.m or more, the fluidity
at the time of blending in the resin can be kept favorable, whereas
when it is controlled to not more than 1 .mu.m, the wear of a drill
blade at the time of drilling processing can be suppressed.
[0091] When a cumulative distribution curve by particle size is
determined while defining the whole volume of the particles as
100%, the "average particle size" as referred to in this
specification means a particle size corresponding to just 50% of
the volume, and it can be measured by a particle size distribution
analyzer adopting a laser diffraction scattering method, or the
like.
[0092] It is necessary that a content of the silica is 20% by
volume or more and not more than 60% by volume of the whole of the
resin composition. When the content of the silica is controlled to
20% by volume or more of the whole of the resin composition, low
thermal expansion of the laminate plate can be realized, whereas
when it is controlled to not more than 60% by volume, the
moldability and drilling processability can be kept favorable. The
content of the silica is preferably 30% by volume or more and not
more than 60% by volume, and more preferably 40% by volume or more
and not more than 56% by volume.
[0093] It is necessary to use, as the component (G), at least one
molybdenum compound selected from zinc molybdate, calcium
molybdate, and magnesium molybdate.
[0094] At the time of using such a molybdenum compound together
with the silica for a laminate plate, the effect for preventing a
lowering of the drilling processability is larger than that in
burnt talc or the like, and the electrical insulating properties
are not significantly lowered unlikely those in molybdenum
disulfide. At the time of blending such a molybdenum compound, a
particle thereof may be used as it is, or such a molybdenum
compound may be used upon being supported on a particle of talc,
silica, zinc oxide, calcium carbonate, magnesium hydroxide, or the
like. On that occasion, an average particle size of such a particle
is preferably 0.3 .mu.m or more and not more than 3 .mu.m, and more
preferably 0.5 .mu.m or more and not more than 2 .mu.m.
[0095] When the average particle size is controlled to 0.3 .mu.m or
more, the dispersibility at the time of blending in the resin can
be kept favorable, whereas when it is controlled to not more than 3
.mu.m, the abrupt precipitation in the case of dissolving the resin
composition in an organic solvent to form a varnish can be
prevented from occurring.
[0096] A content of the molybdenum compound is preferably 0.1% by
volume or more and not more than 10% by volume, and more preferably
0.2% by volume or more and not more than 7% by volume of the whole
of the resin composition.
[0097] When the content of the molybdenum compound is controlled to
0.1% by volume or more, the drilling processability of a laminate
plate can be kept favorable, whereas when it is controlled to not
more than 10% by volume, a lowering of the moldability can be
prevented from occurring.
[0098] In the thermosetting resin composition according to the
present invention, in addition to the foregoing, known
thermoplastic resin, elastomer, inorganic filler, organic filler,
flame retarder, ultraviolet ray absorber, antioxidant, and adhesion
enhancer, and the like can be arbitrarily used.
[0099] Examples of such a thermoplastic resin include polyethylene,
polypropylene, polystyrene, a polyphenylene ether resin, a phenoxy
resin, a polycarbonate resin, a polyester resin, a polyamide resin,
a polyamide-imide resin, a polyimide resin, a xylene resin, a
polyphenylene sulfide resin, a polyether imide resin, a
polyetheretherketone resin, a polyether imide resin, a silicone
resin, a tetrafluoroethylene resin, and so on.
[0100] Examples of the elastomer include polybutadiene,
acrylonitrile, epoxy-modified polybutadiene, maleic
anhydride-modified polybutadiene, phenol-modified polybutadiene,
carboxy-modified acrylonitrile, and so on.
[0101] Examples of the inorganic filler include alumina, talc,
mica, kaolin, aluminum hydroxide, magnesium hydroxide, zinc borate,
zinc stannate, zinc oxide, titanium oxide, boron nitride, calcium
carbonate, barium sulfate, aluminum borate, potassium titanate, a
glass powder of E-glass, S-glass, D-glass, etc., a hollow glass
bead, and so on.
[0102] Examples of the organic filler include a resin particle
having a homogeneous structure, which is composed of polyethylene,
polypropylene, polystyrene, a polyphenylene ether resin, a silicone
resin, a tetrafluoroethylene resin, or the like; a resin particle
of a core-shell structure having a core layer in a rubber state,
which is composed of an acrylic acid ester based resin, a
methacrylic acid ester based resin, a conjugated diene based resin,
or the like, and a shell layer in a vitreous state, which is
composed of an acrylic acid ester based resin, a methacrylic acid
ester based resin, an aromatic vinyl based resin, a vinyl cyanide
based resin, or the like; and so on.
[0103] Examples of the flame retarder include a halogen-containing
flame retarder containing bromine or chlorine; a phosphorus based
flame retarder such as triphenyl phosphate, tricresyl phosphate,
trisdichloropropyl phosphate, red phosphorus, etc.; a nitrogen
based flame retarder such as guanidine sulfamate, melamine sulfate,
melamine polyphosphate, melamine cyanurate, etc.; a phosphazene
based flame retarder such as cyclophosphazene, polyphosphazene,
etc.; an inorganic flame retarder such as antimony trioxide, etc.;
and so on.
[0104] Examples of the ultraviolet ray absorber include a
benzotriazole based ultraviolet ray absorber and so on; examples of
the antioxidant include a hindered phenol based or hindered amine
based antioxidant; and examples of the adhesion enhancer include a
coupling agent such as a silane series, a titanate series, and an
aluminate series, and so on.
[0105] The laminate plate for wiring boards of the present
invention can be obtained by laminating and molding a material
obtained by coating the thermoplastic resin composition using the
foregoing components according to the present invention on a base
material in a film form or fiber form, followed by semi-curing. At
the time of coating the thermosetting resin composition according
to the present invention, it is preferable to use the subject
thermosetting resin composition after being dissolved in an organic
solvent to form a varnish. By coating the resin composition after
being varnished, a laminate plate which is homogenous and less in a
defect such as a void, etc. can be obtained.
[0106] Examples of the organic solvent which is used at the time of
varnishing the thermosetting resin composition include an alcohol
based solvent such as methanol, ethanol, propanol, butanol, methyl
cellosolve, butyl cellosolve, propylene glycol monomethyl ether,
etc.; a ketone based solvent such as acetone, methyl ethyl ketone,
methyl isobutyl ketone, cyclohexanone, etc.; an ester based solvent
such as butyl acetate, propylene glycol monomethyl ether acetate,
etc.; an ether based solvent such as tetrahydrofuran, etc.; an
aromatic solvent such as toluene, xylene, mesitylene, etc.; a
nitrogen atom-containing solvent such as dimethylformamide,
dimethylacetamide, N-methylpyrrolidone, etc.; a sulfur
atom-containing solvent such as dimethyl sulfoxide, etc.; and so
on. These can be used singly or in admixture of two or more kinds
thereof.
[0107] Of these, from the standpoint of solubility of the resin,
methyl cellosolve, propylene glycol monomethyl ether, methyl ethyl
ketone, methyl isobutyl ketone, and cyclohexanone are preferable;
and from the standpoint of low toxicity, propylene glycol
monomethyl ether, methyl isobutyl ketone, and cyclohexanone are
more preferable.
[0108] A proportion of the resin composition in the varnish is
preferably 50% by mass or more and not more than 80% by mass of the
whole of the varnish. By allowing the proportion of the resin
composition in the varnish to fall within the range of 50% by mass
or more and not more than 80% by mass, the coating properties on
the base material can be kept favorable.
[0109] As for the base material which is used at the time of
coating, examples of the base material in a film form include a
metal foil made of copper, aluminum, etc.; and an organic film made
of polyethylene terephthalate, polyimide, etc. Examples of the base
material in a fiber form include fibers of an inorganic material
such as E-glass, D-glass, S-glass, Q-glass, etc.; fibers of an
organic material such as aramid, polyester,
polytetrafluoroethylene, etc.; and mixtures thereof such as a woven
fabric, a nonwoven fabric, a roving mat, a chopped strand mat, and
a surfacing mat.
[0110] Above all, it is preferable to use a woven fabric of fibers
of an inorganic material such as E-glass, S-glass, D-glass,
Q-glass, etc., namely a glass cloth. By using a glass cloth as the
base material, it is possible to satisfy both low thermal expansion
and high drilling processability of the laminate plate.
[0111] In the case of using a glass cloth as the base material,
those having been subjected to a mechanical opening treatment, or
those having been subjected to a surface treatment with a coupling
agent, etc. can be used in a thickness of from 0.01 mm to 0.2
mm.
[0112] In order to obtain a prepreg by coating a thermoplastic
resin composition varnish on a glass cloth and semi-curing it, for
example, there can be adopted a method in which after the glass
cloth is dipped in the resin composition varnish to impregnate the
varnish therein, an attachment amount of the varnish is adjusted
using a cut bar, a squeeze roll, or the like such that a proportion
of the resin composition in the prepreg is from 20% by mass to 90%
by mass, and the resultant is subsequently allowed to pass through
a drying furnace at from about 100.degree. C. to 200.degree. C. for
from about one minute to 30 minutes, thereby achieving semi-curing,
or the like.
[0113] In order to obtain the laminate plate of the present
invention by laminating and molding the thus obtained prepreg, for
example, there can be adopted a method in which from 1 to 20 sheets
of the prepreg are superimposed so as to have a required thickness,
a metal foil such as copper, aluminum, etc. is disposed on one
surface or both surfaces thereof, and heat pressure molding is
performed under a condition at a temperature of from about 100 to
250.degree. C. under a pressure of from about 0.2 to 10 MPa for
from about 0.1 to 5 hours by using a multi-stage press, a
multi-stage vacuum press, a continuous molding machine, an
autoclave molding machine, etc., or the like.
[0114] Next, a manufacturing method of the resin composition
varnish of the present invention is described.
[Manufacturing Method of Resin Composition Varnish]
[0115] The manufacturing method of the resin composition varnish of
the present invention includes a first dispersing and mixing step
of dispersing and mixing (I) a molybdenum compound in (H) a slurry
containing a prescribed silica particle, a second dispersing and
mixing step of dispersing and mixing the slurry having gone through
the first dispersing and mixing step in a varnish containing (J) a
thermosetting resin, and a third dispersing and mixing step of
dispersing and mixing (K) an inorganic filler in the varnish having
gone through the second dispersing and mixing step.
(First Dispersing and Mixing Step)
[0116] The silica particle in the slurry (H) in the first
dispersing and mixing step is required to have an average particle
size of 0.01 .mu.m or more and not more than 0.1 .mu.m and a
specific surface area of 30 m.sup.2/g or more and not more than 270
m.sup.2/g.
[0117] When the average particle size is 0.01 .mu.m or more and not
more than 0.1 .mu.m, and the specific surface area is 30 m.sup.2/g
or more and not more than 270 m.sup.2/g, at the time of dispersing
and mixing the molybdenum compound, the molybdenum compound can be
stably kept in a finely dispersed state such that it does not
precipitate over a long period of time.
[0118] Incidentally, when a cumulative distribution curve by
particle size is determined while defining the whole volume of the
particles as 100%, the "average particle size" as referred to in
this specification means a particle size corresponding to just 50%
of the volume, and it can be measured by a particle size
distribution analyzer adopting a laser diffraction scattering
method, or the like.
[0119] Also, the "specific surface area" refers to a total sum of
surface areas of the whole of particles contained in the powder per
unit mass, and it can be measured by a specific surface area
analyzer adopting the BET method, or the like.
[0120] Examples of the organic solvent in the slurry include an
alcohol such as methanol, ethanol, propanol, butanol, etc.; a
glycol ether such as methyl cellosolve, butyl cellosolve, propylene
glycol monomethyl ether, etc.; and a ketone such as acetone, methyl
ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.
[0121] Of these, from the standpoint that the dispersibility of the
molybdenum compound is easily kept in the second dispersing and
mixing step, an organic solvent the same as the organic solvent
which is used for the varnish containing (J) a thermosetting resin
is preferable.
[0122] A blending amount of the silica particle in the slurry is
preferably 10% by mass or more and not more than 50% by mass, and
more preferably 20% by mass or more and not more than 40% by mass.
When the blending amount is 10% by mass or more and not more than
50% by mass, the dispersibility of the silica particle in the
slurry is excellent, and the dispersibility and stability of the
molybdenum compound are favorable.
[0123] As the silica slurry satisfying the foregoing requirements,
for example, there can be exemplified ADMANANO, manufactured by
Admatechs Company Limited.
[0124] Examples of the molybdenum compound (I) include molybdenum
trioxide, zinc molybdate, ammonium molybdate, magnesium molybdate,
calcium molybdate, barium molybdate, sodium molybdate, potassium
molybdate, phosphomolybdic acid, ammonium phosphomolybdate, sodium
phosphomolybdate, silicomolybdic acid, molybdenum disulfide,
molybdenum diselenide, molybdenum ditelluride, molybdenum boride,
molybdenum disilicide, molybdenum nitride, molybdenum carbide, and
so on. These can be used singly or in admixture of two or more
kinds thereof.
[0125] Of these, zinc molybdate, calcium molybdate, and magnesium
molybdate are preferable because these compounds have low water
solubility and low toxicity, have high electrical insulating
properties, and have a large improving effect of drilling
processability.
[0126] In the case of defining the volume of the silica particle
contained in the slurry as 1, a blending amount of the molybdenum
compound in the silica slurry is preferably 0.2 or more and not
more than 5, and more preferably 0.3 or more and not more than 4 in
terms of a volume ratio (Mo compound/SiO.sub.2). When the volume
ratio is 0.2 or more and not more than 5, at the time of dispersing
and mixing the molybdenum compound in the slurry, the
dispersibility and stability are favorable.
[0127] Examples of a method for dispersing and mixing the
molybdenum compound in the silica slurry in the first dispersing
and mixing step include a method in which the molybdenum compound
is first gradually added and well mixed while stirring the slurry,
and the mixture is subsequently subjected to a dispersion treatment
by a media mill such as a bead mill, a ball mill, etc., a
high-speed disperser such as a dissolver, etc., a high-pressure
homogenizer such as a nanomizer, etc., a colloid mill, an
ultrasonic processor, or the like.
[0128] Above all, a method for performing the treatment by a
high-speed homogenizer is preferable because incorporation of
impurities is small, and the dispersion can be efficiently
achieved. Also, a coupling agent such as a silane series, a
titanate series, an aluminate series, etc., a modified silicone
such as polyether-modified polysiloxane, etc., a polycarboxylic
acid, a polymer dispersant such as a urethane series, an acrylate
series, etc., or the like can also be added as a dispersant at the
time of dispersing and mixing.
(Second Dispersing and Mixing Step)
[0129] Examples of the thermosetting resin (J) in the step of the
second dispersing and mixing step include an epoxy resin, a phenol
resin, an unsaturated imide resin, a cyanate resin, an isocyanate
resin, a benzoxazine resin, an oxetane resin, an amino resin, an
unsaturated polyester resin, an allyl resin, a dicyclopentadiene
resin, a silicone resin, a triazine resin, a melamine resin, and so
on. These can be used singly or in admixture of two or more kinds
thereof.
[0130] Of these, an epoxy resin is preferable from the standpoints
of moldability and electrical insulating properties.
[0131] Examples of such an epoxy resin include a bisphenol A type
epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type
epoxy resin, a phenol novolak type epoxy resin, a cresol novolak
type epoxy resin, a bisphenol A novolak type epoxy resin, a
bisphenol F novolak type epoxy resin, a biphenyl type epoxy resin,
a xylylene type epoxy resin, a biphenyl aralkyl type epoxy resin, a
naphthalene type epoxy resin, a dicyclopentadiene type epoxy resin,
an alicyclic epoxy resin, a diglycidyl ether compound of a
polyfunctional phenol or a polycyclic aromatic compound such as
anthracene, etc., and so on. These can be used singly or in
admixture of two or more kinds thereof.
[0132] In the case of using an epoxy resin as the thermosetting
resin, a curing agent of the epoxy resin can be used, as the need
arises.
[0133] Examples of the curing agent include a polyfunctional phenol
compound such as phenol novolak, cresol novolak, etc.; an amine
compound such as dicyandiamide, diaminodiphenylmethane,
diaminodiphenylsulfone, etc.; an acid anhydride such as phthalic
anhydride, pyromellitic anhydride, maleic anhydride, a maleic
anhydride copolymer, etc.; and so on. These can be used singly or
in admixture of two or more kinds thereof.
[0134] Examples of the organic solvent which is used for the
varnish containing a thermosetting resin include an alcohol based
solvent such as methanol, ethanol, propanol, butanol, methyl
cellosolve, butyl cellosolve, propylene glycol monomethyl ether,
etc.; a ketone based solvent such as acetone, methyl ethyl ketone,
methyl isobutyl ketone, cyclohexanone, etc.; an ester based solvent
such as butyl acetate, propylene glycol monomethyl ether acetate,
etc.; an ether based solvent such as tetrahydrofuran, etc.; an
aromatic solvent such as toluene, xylene, mesitylene, etc.; a
nitrogen atom-containing solvent such as dimethylformamide,
dimethylacetamide, N-methylpyrrolidone, etc.; a sulfur
atom-containing solvent such as dimethyl sulfoxide, etc.; and so
on. These can be used singly or in admixture of two or more kinds
thereof.
[0135] Of these, from the standpoints of excellent solubility of
the thermosetting resin and low toxicity, methyl ethyl ketone,
methyl isobutyl ketone, cyclohexanone, and propylene glycol
monomethyl ether are preferable.
[0136] A solid content concentration of the varnish containing a
thermosetting resin is preferably 40% by mass or more and not more
than 90% by mass, and more preferably 50% by mass or more and not
more than 80% by mass. By allowing the solid content of the varnish
to fall within the range of 40% by mass or more and not more than
90% by mass, the dispersibility and stability of the molybdenum
compound in the second dispersing and mixing step can be kept
favorable.
[0137] When the whole of the resin composition excluding the
organic solvent finally contained in the resin composition varnish
is defined as 100% by volume, a blending amount of the slurry
having the molybdenum compound dispersed therein into the varnish
is preferably 0.1% by volume or more and not more than 10% by
volume in terms of an amount of the molybdenum compound. By
allowing the amount of the molybdenum compound to fall within the
range of 0.1% by volume or more and not more than 10% by volume, it
is possible to realize low thermal expansion of the resin
composition while keeping the drilling processability
favorable.
[0138] Examples of a method for dispersing and mixing the slurry
having the molybdenum compound dispersed therein in the varnish
containing a thermosetting resin in the second dispersing and
mixing step include a method in which the slurry is gradually added
and well mixed while stirring the varnish.
(Third Dispersing and Mixing Step)
[0139] As the inorganic filler (K) in the third dispersing and
mixing step, various material exclusive of the silica particle as
the already-described component (H) and the molybdenum compound as
the already-described component (I) can be used. Examples thereof
include silica, alumina, talc, mica, kaolin, aluminum hydroxide,
magnesium hydroxide, zinc borate, zinc stannate, zinc oxide,
titanium oxide, boron nitride, calcium carbonate, barium sulfate,
aluminum borate, potassium titanate, a glass powder of E-glass,
S-glass, D-glass, etc., a hollow glass bead, and so on. These can
be used singly or in admixture of two or more kinds thereof.
[0140] Of these, silica is preferable from the standpoint of its
low coefficient of thermal expansion.
[0141] Examples of the silica include precipitated silica which is
manufactured by a wet process and which has a high water content;
and dry process silica which is manufactured by a dry process and
which does not substantially contain bonding water, etc.
Furthermore, the dry process silica includes crushed silica, fumed
silica, and fused spherical silica depending upon a difference of
the manufacturing method. Of these, from the standpoint of
excellent fluidity upon being filled in the resin, fused spherical
silica is preferable.
[0142] In the case of using fused spherical silica as the inorganic
filler, its average particle size is preferably from 0.1 .mu.m or
more and not more than 10 .mu.m, and more preferably from 0.3 .mu.m
or more and not more than 8 .mu.m. When the average particle size
of the fused spherical silica is controlled to 0.1 .mu.m or more,
the fluidity at the time of filling in the resin can be kept
favorable, whereas when it is controlled to not more than 10 .mu.m,
a probability of incorporation of coarse particles is reduced,
thereby enabling one to suppress the generation of failure.
[0143] Incidentally, the average particle size is made to be larger
than that of the silica particle as the already-described component
(H).
[0144] When the whole of the resin composition excluding the
organic solvent finally contained in the resin composition varnish
is defined as 100% by volume, a blending amount of the inorganic
filler into the varnish is preferably 20% by volume or more and not
more than 60% by volume, and more preferably 30% by volume or more
and not more than 55% by volume. By allowing the blending amount of
the inorganic filler to fall within the range of 20% by volume or
more and not more than 60% by volume, it is possible to realize low
thermal expansion of the resin composition while keeping the
moldability favorable.
[0145] Examples of a method for dispersing and mixing the inorganic
filler in the varnish containing the molybdenum compound and the
thermosetting resin in the third dispersing and mixing step include
a method in which the inorganic filler is added as it is and mixed;
and a method in which the inorganic filler is dispersed in the
organic solvent in advance to form a slurry, which is then added
and mixed.
[0146] Of these, from the standpoint of dispersibility of the
inorganic filler in the varnish, a method in which the inorganic
filler is converted into a slurry and then added is preferable. At
the time of converting the inorganic filler into a slurry, it is
preferable to subject the inorganic filler to a pre-treatment with
a surface treating agent such as a coupling agent, e.g., a silane
series, a titanate series, etc., a silicone oligomer, or the like
in advance, or to an integral blend treatment.
[0147] In the resin composition varnish having been manufactured
through the foregoing respective steps, in addition to the
foregoing components, a curing accelerator, a thermoplastic resin,
an elastomer, an organic filler, a flame retarder, an ultraviolet
ray absorber, an antioxidant, an adhesion enhancer, and the like
can be added and used.
[0148] Examples of the curing accelerator include an imidazole and
a derivative thereof, an organic phosphorus based compound, a
secondary amine, a tertiary amine, a quaternary ammonium salt, and
so on. These can be used singly or in admixture of two or more
kinds thereof.
[0149] Examples of the thermoplastic resin include polyethylene,
polypropylene, polystyrene, a polyphenylene ether resin, a phenoxy
resin, a polycarbonate resin, a polyester resin, a polyamide resin,
a polyamide-imide resin, a polyimide resin, a xylene resin, a
polyphenylene sulfide resin, a polyether imide resin, a
polyetheretherketone resin, a polyether imide resin, a silicone
resin, a tetrafluoroethylene resin, and so on.
[0150] Examples of the elastomer include polybutadiene,
acrylonitrile, epoxy-modified polybutadiene, maleic
anhydride-modified polybutadiene, phenol-modified polybutadiene,
carboxy-modified acrylonitrile, and so on.
[0151] Examples of the organic filler include a resin filler having
a homogeneous structure, which is composed of polyethylene,
polypropylene, polystyrene, a polyphenylene ether resin, a silicone
resin, a tetrafluoroethylene resin, or the like; a resin filler of
a core-shell structure having a core layer in a rubber state, which
is composed of an acrylic acid ester based resin, a methacrylic
acid ester based resin, a conjugated diene based resin, or the
like, and a shell layer in a vitreous state, which is composed of
an acrylic acid ester based resin, a methacrylic acid ester based
resin, an aromatic vinyl based resin, a vinyl cyanide based resin,
or the like; and so on.
[0152] Examples of the flame retarder include a halogen-containing
flame retarder containing bromine or chlorine; a phosphorus based
flame retarder such as triphenyl phosphate, tricresyl phosphate,
trisdichloropropyl phosphate, red phosphorus, etc.; a nitrogen
based flame retarder such as guanidine sulfamate, melamine sulfate,
melamine polyphosphate, melamine cyanurate, etc.; a phosphazene
based flame retarder such as cyclophosphazene, polyphosphazene,
etc.; an inorganic flame retarder such as antimony trioxide, etc.;
and so on.
[0153] Besides, examples of the ultraviolet ray absorber include a
benzotriazole based ultraviolet ray absorber and so on; examples of
the antioxidant include a hindered phenol based or hindered amine
based antioxidant; and examples of the adhesion enhancer include a
coupling agent such as a silane series, a titanate series, an
aluminate series, etc.
[0154] Incidentally, it is preferable to carryout the addition of
these components to the resin composition varnish after the third
dispersing and mixing step. Also, a solid content of the finally
obtained resin composition varnish is preferably from 40 to 80% by
mass, and more preferably from 45 to 75% by mass.
[0155] When the solid content is from 40 to 80% by mass, the
coating properties of the varnish are favorable, and a prepreg
having an appropriate attachment amount of the resin composition
can be obtained.
[Prepreg and Laminate Plate]
[0156] Next, a prepreg and a laminate plate each using the
foregoing resin composition varnish are described.
(Prepreg)
[0157] The prepreg of the present invention is one obtained by
impregnating or coating a base material with the resin composition
varnish obtained by the already-described method for manufacturing
a resin composition varnish of the present invention and then
performing semi-curing (B-staging) by heating or the like.
[0158] Examples of the base material which is used for the prepreg
of the present invention include fibers of an inorganic material
such as E-glass, D-glass, S-glass, Q-glass, etc.; fibers of an
organic material such as an aramid resin, a polyester resin, a
tetrafluoroethylene resin, etc.; and mixtures thereof.
[0159] Though such a base material has a form of, for example, a
woven fabric, a nonwoven fabric, a roving, a chopped strand mat, a
surfacing mat, etc., the material and the shape are selected
depending on an application or a performance of the target laminate
plate, and the material and the shape can be employed solely or in
combination of two or more kinds thereof, as the need arises. Also,
those having been subjected to a surface treatment with a silane
coupling agent, etc., or those having been subjected to a
mechanical opening treatment are preferable from the standpoints of
heat resistance, moisture resistance, and processability. As for a
thickness of the base material, for example, those having a
thickness of from 0.01 to 0.2 mm can be used.
(Laminate Plate)
[0160] The laminate plate of the present invention is one obtained
by lamination and molding by using the prepreg of the present
invention. For example, a metal clad laminate plate can be
manufactured by performing lamination and molding in a
configuration in which from 1 to 20 sheets of the prepreg of the
present invention are superimposed, and a metal foil such as
copper, aluminum, etc. is disposed on one surface or both surfaces
thereof, within the range at a temperature of from about 100 to
250.degree. C. under a pressure of from about 0.2 to 10 MPa for a
heating time of from about 0.1 to 5 hours by using a press, a
vacuum press, a continuous molding machine, an autoclave molding
machine, or the like.
[0161] The metal foil is not particularly limited so far as it is
one to be used for an application of electronic components. Also, a
multi-layered board can be manufactured by combining the prepreg of
the present invention with a wiring board for internal layer and
laminating and molding the combination.
[0162] Each of the above-described prepreg and laminate plate of
the present invention has such characteristic features as a low
coefficient of thermal expansion and high drilling
processability.
EXAMPLES
[0163] Next, the present invention is described in more detail with
reference to the following Examples, but it should be construed
that these Examples do not limit the present invention.
Manufacturing Example 1
Manufacture of Maleimide Compound (A-1)
[0164] In a reaction vessel having a capacity of 2 liters and
capable of being heated and cooled, which was equipped with a
thermometer, an agitator, and a reflux condenser-equipped water
quantity meter, 358.0 g of bis(4-maleimidophenyl)methane, 54.5 g of
p-aminophenol, and 412.5 g of propylene glycol monomethyl ether
were charged and allowed to react with each other for 5 hours while
refluxing, thereby obtaining a maleimide compound (A-1).
Manufacturing Example 2
Manufacture of Maleimide Compound (A-2)
[0165] In a reaction vessel having a capacity of 2 liters and
capable of being heated and cooled, which was equipped with a
thermometer, an agitator, and a reflux condenser-equipped water
quantity meter, 358.0 g of bis(4-maleimidophenyl) methane, 68.5 g
of p-aminobenzoic acid, and 322.5 g of N-dimethylacetamide were
charged and allowed to react with each other at 140.degree. C. for
5 hours, thereby obtaining a maleimide compound (A-2).
Examples 1 to 3
[0166] The unsaturated maleimide compound (A) having an acidic
substituent obtained in Manufacturing Example 1 or 2, and (B) a
thermosetting resin and a curing accelerator, (C) an inorganic
filler, and (D) a molybdenum compound as described below were
dispersed and dissolved in a blending proportion shown in Table 1
in propylene glycol monomethyl ether, thereby obtaining a
homogeneous varnish having a content of the resin composition of
70% by mass. This resin composition varnish was impregnated and
coated on an E-glass cloth [WEA116E, manufactured by Nitto Boseki
Co., Ltd.] having a thickness of 0.1 mm, followed by heating for
drying at 150.degree. C. for 5 minutes to obtain a prepreg having a
content of the resin composition of 50% by mass. Four sheets of
this prepreg were superimposed, and an 18 .mu.m-thick electrolytic
copper foil was disposed on the top and bottom, followed by vacuum
pressing under a pressure of 3.5 MPa at a temperature of
185.degree. C. for 90 minutes, thereby obtaining a copper clad
laminate plate.
[0167] Each of the obtained copper clad laminate plates was used
and then measured and evaluated with respect to drilling
processability, coefficient of thermal expansion, and heat
resistance by the following methods. The results are shown in Table
1.
(B) Thermosetting Resin:
[0168] B-1: Biphenyl aralkyl type epoxy resin [NC-3000,
manufactured by Nippon Kayaku Co., Ltd.]
[0169] B-2: Phenol novolak type epoxy resin [EPICLON N-770,
manufactured by DIC Corporation]
[0170] B-3: Cresol novolak type phenol resin [PHENOLITE KA-1165,
manufactured by DIC Corporation]
Curing accelerator: 2-Ethyl-4-methyl imidazole [2E4MI, manufactured
by Shikoku Chemicals Corporation]
(C) Inorganic Filler:
[0171] C-1: Fused spherical silica slurry [SC2050-KC, manufactured
by Admatechs Company Limited, average particle size: 0.5 .mu.m,
solid content: 70% by mass]
[0172] C-2: Aluminum hydroxide [CL-310, manufactured by Sumitomo
Chemical Co., Ltd.]
[0173] C-3: Burnt talc [ST-100, manufactured by Fuji Talc
Industrial Co., Ltd.]
(D) Molybdenum Compound:
[0174] D-1: Zinc molybdate [a reagent, manufactured by Strem
Chemicals Inc.]
[0175] D-2: Zinc molybdate-supported talc [KEMIGARD 911C,
manufactured by Sherwin-Williams Company, zinc molybdate: 20% by
mass]
[0176] D-3: Calcium molybdate [a reagent, manufactured by Strem
Chemicals Inc.]
Comparative Example 1
[0177] A copper clad laminate plate using a resin composition was
obtained in the same manner as that in Example 1, except that the
molybdenum compound (D) was not blended. The measurement and
evaluation results are shown in Table 1.
Comparative Example 2
[0178] A copper clad laminate plate using a resin composition was
obtained in the same manner as that in Example 1, except that the
unsaturated maleimide compound (A) having an acidic substituent was
not blended. The measurement and evaluation results are shown in
Table 1.
Comparative Example 3
[0179] A copper clad laminate plate using a resin composition was
obtained in the same manner as that in Example 1, except that the
inorganic filler (C) was not blended. The measurement and
evaluation results are shown in Table 1.
<Evaluation of Drilling Processability, Coefficient of Thermal
Expansion, and Heat Resistance of Copper Clad Laminate
Plate>
(1) Evaluation of Drilling Processability:
[0180] Two sheets of the copper clad laminate plate were
superimposed; an aluminum foil having a thickness of 0.1 mm was
disposed thereabove, whereas a paper phenol board having a
thickness of 1.5 mm was disposed thereunder; 6,000 holes were
drilled with a drill having a diameter of 0.2 mm by using a
drilling machine [ND-1V212, manufactured by Hitachi Via Mechanics,
Ltd.] under a condition at a rotation number of 160 krpm and a feed
rate of 2 m/min under a chip load of 12.5 .mu.m/rev; and a wear
amount of drill cutting blade and hole registration accuracy were
measured by the following methods, thereby evaluating the drilling
processability.
(a) Wear Amount of Drill Cutting Blade:
[0181] A drilling cutting blade portion before and after drilling
was observed from the drill central axis by using an inspection
microscope [MX50, manufactured by Olympus Corporation], and a wear
retreat amount of cutting blade edge was measured and defined as
the wear amount of drill cutting blade.
(b) Hole Registration Accuracy:
[0182] Of the two-ply copper clad laminate plates, a registration
deviation amount of holes of the lower side (drill exit side) of
the second sheet was measured using a hole registration accuracy
analyzer [HT-1AM, manufactured by Hitachi Via Mechanics, Ltd.], and
average+3.sigma. (.sigma.: standard deviation) of registration
deviation amounts of the 4,001st to 6,000th hit holes was
calculated and defined as the hole registration accuracy.
(2) Measurement of Coefficient of Thermal Expansion:
[0183] After removing the copper foil of the copper clad laminate
plate with an etching liquid, the resulting laminate plate was cut
into a size of 5 mm square, thereby fabricating a specimen. A
coefficient of thermal expansion of this specimen in the machine
direction (longitudinal direction of the glass cloth) at from
50.degree. C. to 120.degree. C. was measured at a temperature
rising rate of 10.degree. C./min by using a TMA test apparatus
(TMA2940, manufactured by TA Instruments).
(3) Evaluation of Heat Resistance (Glass Transition
Temperature):
[0184] After removing the copper foil of the copper clad laminate
plate with an etching liquid, the resulting laminate plate was cut
into a size of 5 mm square, thereby fabricating a specimen. A
temperature-dimension change curve of this specimen in the
thickness direction was measured at a temperature rising rate of
10.degree. C./min by using a TMA test apparatus (TMA2940,
manufactured by Du Pont), and a temperature of a point of
intersection between an approximate straight line of low
temperature side and an approximate straight line of high
temperature side in the temperature-dimension change curve was
determined as a glass transition temperature and evaluated for the
heat resistance.
TABLE-US-00001 TABLE 1 Comparative Comparative Comparative Example
1 Example 2 Example 3 Example 1 Example 2 Example 3 Use amount
(parts by mass) A: Unsaturated maleimide compound having an acidic
substituent A-1 (Manufacturing Example 1) 65 65 65 65 A-2
(Manufacturing Example 2) 50 B: Thermosetting resin B-1 (Biphenyl
aralkyl type epoxy resin) 35 35 35 35 B-2 (Phenol novolak type
epoxy resin) 50 61 B-3 (Cresol novolak type phenol resin) 39 Curing
accelerator: 2-Ethyl-4-methyl 0.5 0.25 0.5 0.5 0.15 0.5 imidazole
C: Inorganic filler C-1 (Fused spherical silica slurry: 199 124 81
199 124 SC2050-KC) C-2: (Aluminum hydroxide: CL-310) 34 34 C-3:
(Burnt talc: ST-100) 48 54 D: Molybdenum compound D-1 (Zinc
molybdate) 86 154 D-2 (Zinc molybdate-supported talc, 6.0 6.0 10%
supported) D-3 (Calcium molybdate) 5.6 Composition (% by volume) A
+ B: Unsaturated maleimide compound + 50 60 79 50 60 70
Thermosetting resin C: Inorganic filler 38 38.5 20 38 38.5 D:
Molybdenum compound 12 1.5 1.0 12 1.5 30 Measurement and evaluation
(1) Drilling processability Wear amount of drill cutting blade
(.mu.m) 11 9 7 31 8 5 Hole registration accuracy (.mu.m) 31 30 28
48 29 25 (2) Coefficient of thermal expansion (10.sup.-6/.degree.
C.) 10.8 11.4 11.7 10.7 14.1 14.5 (3) Heat resistance (glass
transition 210 220 215 212 175 199 temperature: .degree. C.)
[0185] The use amount (parts by mass) in Table 1 is a blending
amount of each of the components regarding the resin compositions
of the Examples and Comparative Examples, as expressed in terms of
parts by mass in the case where a total sum blending amount of the
unsaturated maleimide compound (A) having an acidic substituent and
the thermosetting resin (B) is defined as 100 parts by mass.
However, in Comparative Example 2, since the maleimide compound (A)
is not blended, the total sum blending amount of the thermosetting
resin (B) and the cresol novolak type phenol resin was shown as 100
parts by mass.
[0186] As is clear from Table 1, all of the Examples of the present
invention are low in the coefficient of thermal expansion and
excellent in the drilling processability and heat resistance.
[0187] On the other hand, though Comparative Example 1 is low in
the coefficient of thermal expansion and excellent in the heat
resistance, it is significantly inferior in the drilling
processability because the molybdenum compound (D) of the present
invention is not contained therein.
[0188] Also, though Comparative Examples 2 and 3 are excellent in
the drilling processability, they are high in the coefficient of
thermal expansion and inferior in the heat resistance because the
unsaturated maleimide compound (A) having an acidic substituent or
the inorganic filler (C) of the present invention is not contained
therein.
Examples 4, 6 and 7 and Comparative Example 4
[0189] In blends shown in Tables 2 and 3, first of all, (E) a
thermosetting resin and a curing agent were completely dissolved in
an organic solvent; subsequently, (F) a silica slurry was added;
and stirring was performed until the both were thoroughly mixed.
Thereafter, (G) a molybdenum compound was gradually added; stirring
was continued until an aggregated block disappeared; and finally, a
curing accelerator was added, and stirring was performed for one
hour such that the whole of the varnish became homogenous.
[0190] Each of the thus obtained thermosetting resin composition
varnishes was impregnated and coated on an E-glass cloth (WEA116E,
manufactured by Nitto Boseki Co., Ltd.) having a thickness of 0.1
mm, followed by heating for drying at 160.degree. C. for 5 minutes
to achieve semi-curing, thereby obtaining a prepreg having a
proportion of the resin composition of 48% by mass.
[0191] A prescribed number of sheets of this prepreg were
superimposed so as to be a required thickness, an electrolytic
copper foil [GTS-12, manufactured by Furukawa Electric Co., Ltd.]
having a thickness of 12 .mu.m was disposed on the both surfaces,
followed by heat pressure molding under a pressure of 4 MPa at a
temperature of 185.degree. C. for 90 minutes by using a vacuum
press, thereby obtaining a copper clad laminate plate.
Example 5 and Comparative Example 5
[0192] Copper clad laminate plates were obtained in the same manner
as that in Examples 4, 6 and 7 and Comparative Example 4, except
that at the time of blending the thermosetting resin composition
varnish, after adding the silica slurry (F) and before adding the
molybdenum compound (G), an inorganic filler (aluminum hydroxide)
was added, and the components were thoroughly stirred and
mixed.
Comparative Examples 6 and 7
[0193] Copper clad laminate plates were obtained in the same manner
as that in Examples 4, 6 and 7 and Comparative Example 4, except
that at the time of blending the thermosetting resin composition
varnish, after adding the silica slurry (F), an inorganic filler
(burnt talc or molybdenum disulfide) was added; the components were
stirred until an aggregated block disappeared; and finally, a
curing accelerator was added, and stirring was performed for one
hour such that the whole of the varnish became homogenous.
TABLE-US-00002 TABLE 2 Component Example 4 Example 5 Example 6
Example 7 (E) Thermosetting E-1 100 100 resin E-2 60 60 E-3 40 40
Curing agent 52 63 52 63 Curing accelerator 0.3 0.2 0.32 0.25 (F)
Silica F-1 170 (23) 391 (49) 282 (40) F-2 558 (56) (G) Molybdenum
G-1 54.6 (4) compound G-2 13.1 (2) G-3 10.4 (1) G-4 4.5 (0.5)
Inorganic filler 3 96 Organic solvent 89 117 70 72
TABLE-US-00003 TABLE 3 Compar- Compar- Compar- Compar- ative ative
ative ative Component Example 4 Example 5 Example 6 Example 7 (E)
Thermosetting E-1 100 100 resin E-2 60 60 E-3 40 40 Curing agent 52
63 52 63 Curing accelerator 0.25 0.2 0.32 0.35 (F) Silica F-1 110
(15) 391 (49) 282 (40) F-2 824 (62) (G) Molybdenum G-1 146 (8)
compound G-2 6.6 (1) Inorganic filler 1 8.1 Inorganic filler 2 5.4
Inorganic filler 3 148 Organic solvent 128 136 69 72
[0194] Here, a blending amount of each of the components in Tables
2 and 3 was expressed in terms of parts by mass in the case where a
total sum blending amount of the thermosetting resin (E) as defined
as 100. However, with respect to the silica (F) and the molybdenum
compound (G), a value of % by volume relative to the whole of the
resin composition was also expressed in each of the parentheses.
Also, the following materials were used as the respective
components in Tables 2 and 3.
(E) Thermosetting Resin:
[0195] E-1: Phenol novolak type epoxy resin [EPICLON N-770,
manufactured by DIC Corporation]
[0196] E-2: Bisphenol A novolak type epoxy resin [EPICLON N-865,
manufactured by DIC Corporation]
[0197] E-3: Biphenyl aralkyl type epoxy resin [NC-3000,
manufactured by Nippon Kayaku Co., Ltd.]
Curing agent: Cresol novolak type phenol resin [PHENOLITE KA-1165,
manufactured by DIC Corporation] Curing accelerator:
2-Ethyl-4-methylimidazole [CUREZOL 2E4MZ, manufactured by Shikoku
Chemicals Corporation]
(F) Silica:
[0198] F-1: Fused spherical silica slurry [SC2050-KC, manufactured
by Admatechs Company Limited, average particle size: 0.5 .mu.m,
solid content: 70% by mass]
[0199] F-2: Fused spherical silica slurry [SC4050-KNA, manufactured
by Admatechs Company Limited, average particle size: 1.0 .mu.m,
solid content: 70% by mass]
(G) Molybdenum Compound:
[0200] G-1: Zinc molybdate [a reagent, manufactured by Strem
Chemicals Inc., average particle size: 2 .mu.m]
[0201] G-2: Zinc molybdate-supported talc [KEMIGARD 911C,
manufactured by Sherwin-Williams Company, average particle size: 3
.mu.m]
[0202] G-3: Calcium molybdate [a reagent, manufactured by Strem
Chemicals Inc., average particle size: 2 .mu.m]
[0203] G-4: Magnesium molybdate [a reagent, manufactured by Mitsuwa
Chemicals Co., Ltd., average particle size: 3 .mu.m]
Inorganic filler 1: Burnt talc [BST, manufactured by Nippon Talc
Co., Ltd.] Inorganic filler 2: Molybdenum disulfide [A Powder,
manufactured by Nichimoly Division, Daizo Corporation] Inorganic
filler 3: Aluminum hydroxide [C-303, manufactured by Sumitomo
Chemical Co., Ltd.] Organic solvent: Cyclohexanone [manufactured by
Godo Co., Ltd.]
[0204] Each of the copper clad laminate plates obtained in the
foregoing Examples and Comparative Examples was measured and
evaluated with respect to characteristics by the following methods.
The measurement and evaluation results are shown in Tables 4 and
5.
(1) Evaluation of Drilling Processability:
[0205] Two sheets of a copper clad laminate plate having a
thickness of 0.4 mm were superimposed; a paper phenol board having
a thickness of 0.4 mm was disposed thereabove, whereas a paper
phenol board having a thickness of 1.5 mm was disposed thereunder;
6,000 holes were drilled with a drill having a diameter of 0.2 mm
by using a drilling machine [ND-1V212, manufactured by Hitachi Via
Mechanics, Ltd.] under a condition at a rotation number of 160 krpm
and a feed rate of 1.8 m/min under a chip load of 11.25 .mu.m/rev;
and a wear amount of drill cutting blade and hole registration
accuracy were measured by the following methods, thereby evaluating
the drilling processability.
(a) Wear Amount of Drill Cutting Blade:
[0206] A drilling cutting blade portion of a new product (before
drilling) and after drilling was observed from the drill central
axis by using a scanning electron microscope [S-4700, manufactured
by Hitachi, Ltd.], and a wear retreat amount of cutting blade edge
was measured and defined as the wear amount of drill cutting
blade.
(b) Hole Registration Accuracy:
[0207] Of the two-ply copper clad laminate plates, a registration
deviation amount of holes of the lower side (drill exit side) of
the second sheet was measured using a hole registration accuracy
analyzer [HT-1AM, manufactured by Hitachi Via Mechanics, Ltd.], and
average+3.sigma. (.sigma.: standard deviation) of registration
deviation amounts of the 4,001st to 6,000th hit holes was
calculated and defined as the hole registration accuracy. So far as
the hole registration accuracy is not more than 35 .mu.m, favorable
results are revealed without causing a problem in view of the
practical use.
(2) Measurement of Coefficient of Thermal Expansion:
[0208] After removing a copper foil of a copper clad laminate plate
having a thickness of 0.8 mm with an etching liquid, the resulting
laminate plate was cut into a size of 5 mm square, thereby
fabricating a specimen. An average coefficient of linear thermal
expansion of this specimen in the machine direction (longitudinal
direction of the glass cloth) at from 50.degree. C. to 120.degree.
C. was measured at a temperature rising rate of 10.degree. C./min
by using a TMA test apparatus [TMA2940, manufactured by TA
Instruments]. The closer the coefficient of thermal expansion to a
coefficient of thermal expansion of a silicon chip (from
4.times.10.sup.-6/.degree. C. to 5.times.10.sup.-6/.degree. C.),
the more favorable the results are.
(3) Measurement of Electrical Insulating Properties:
[0209] After removing a copper foil on one surface of a copper clad
laminate plate having a thickness of 0.1 mm with an etching liquid
while leaving a circular portion having a diameter of 20 mm, the
resulting laminate plate was cut into a size of 50 mm square such
that the circular portion was located in the center, thereby
fabricating a specimen. This specimen was dipped in FLUORINERT
[manufactured by Sumitomo 3M Limited] and subjected to a dielectric
breakdown test under a condition at a pressure rising rate of 5
kV/10 sec. by using a withstanding voltage meter [PT-1011,
manufactured by TOA Electronics Ltd.], thereby measuring a
dielectric breakdown voltage. So far as the dielectric breakdown
voltage is 6 kV or more, favorable results are revealed without
causing a problem in view of the practical use.
(4) Evaluation of Moldability:
[0210] A copper clad laminate plate having a thickness of 0.4 mm
was cut into a size of 5 mm square and cast with a casting resin,
and the cut surface was polished to fabricate a specimen for cross
section observation. The polished surface of this specimen was
subjected to milling by a flat milling apparatus [E-3200,
manufactured by Hitachi, Ltd.] and then observed by using a
scanning electron microscope [S-4700, manufactured by Hitachi,
Ltd.] to examine the presence or absence of a void, thereby
evaluating the moldability.
TABLE-US-00004 TABLE 4 Item Unit Example 4 Example 5 Example 6
Example 7 Drilling Wear amount of .mu.m 11 8 9 10 processability
drill cutting blade Hole registration .mu.m 34 31 30 31 accuracy
Coefficient of thermal expansion 10.sup.-6/.degree. C. 10.8 13.1
11.3 13.1 Electrical insulating properties kV 6.9 7.7 7.1 8.0
Moldability (presence or absence -- Absent Absent Absent Absent of
void)
TABLE-US-00005 TABLE 5 Comparative Comparative Comparative
Comparative Item Unit Example 4 Example 5 Example 6 Example 7
Drilling Wear amount of .mu.m 18 7 28 13 processability drill
cutting blade Hole registration .mu.m 42 31 50 38 accuracy
Coefficient of thermal expansion 10.sup.-6/.degree. C. 10.3 14.9
11.3 13.2 Electrical insulating properties kV 3.5 7.6 7.1 2.6
Moldability (presence or absence -- Present Absent Absent Absent of
void)
[0211] As is clear from Table 4, all of the Examples of the present
invention are excellent in the drilling processability and low
thermal expansion properties and are of no problem in the
electrical insulating properties and moldability.
[0212] On the other hand, as is clear from Table 5, in Comparative
Example 4, since the content of silica exceeds 60% by volume of the
whole of the resin composition, the moldability is significantly
inferior and lowered in the drilling processability and electrical
insulating properties. In Comparative Example 5, since the content
of silica is less than 20% by volume of the whole of the resin
composition, there is such a problem that the coefficient of
thermal expansion is large. In Comparative Example 6, since the
molybdenum compound of the present invention is not contained, the
drilling processability is significantly inferior. Similarly, in
Comparative Example 7, since the molybdenum compound of the present
invention is not contained, and molybdenum disulfide is contained,
the electrical insulating properties are significantly
inferior.
Examples 8 and 9 and Comparative Examples 8 and 9
[0213] In blends of resin composition varnishes shown in Table 6,
first of all, (I) a molybdenum compound was gradually added to (H)
a silica slurry and mixed while stirring such that an aggregated
block was not formed. This silica slurry having the molybdenum
compound mixed therewith was treated three times under a condition
at an air pressure of 0.5 MPa by using a nanomizer (NM2000-AR,
manufactured by Yoshida Kikai Co., Ltd.), thereby thoroughly
dispersing and mixing the molybdenum compound and the silica
particles.
[0214] Subsequently, this molybdenum compound-dispersed silica
slurry was gradually added to a resin varnish which had been
prepared by dissolving (J) a thermosetting resin and a curing agent
in an organic solvent, while stirring, and after the whole amount
was completely added, the components were stirred for one hour
until the whole became homogenous.
[0215] Thereafter, (K) an inorganic filler slurry was added to the
resin varnish while stirring, to which was then further added a
curing accelerator, and the components were stirred for one hour
until the whole became homogenous, thereby preparing a resin
composition varnish.
[0216] A solid content concentration of each of the resin
composition varnishes of Examples 8 and 9 and Comparative Examples
8 and 9 was 70% by mass.
Comparative Example 10
[0217] In a blend of a resin composition varnish shown in Table 6,
(I) a molybdenum compound was gradually added to a resin varnish
which had been prepared by dissolving (J) a thermosetting resin and
a curing agent in an organic solvent, while stirring, and after the
whole amount was completely added, the components were stirred for
one hour until the whole became homogenous.
[0218] Thereafter, (K) an inorganic filler slurry was added to the
resin varnish while stirring, to which was then further added a
curing accelerator, and the components were stirred for one hour
until the whole became homogenous, thereby preparing a resin
composition varnish.
[0219] A solid content concentration of the resin composition
varnishes of Comparative Example 10 was 70% by mass.
Comparative Example 11
[0220] In a blend of a resin composition varnish shown in Table 6,
first of all, (I) a molybdenum compound was gradually added to (H)
a silica slurry and mixed while stirring such that an aggregated
block was not formed. This silica slurry having the molybdenum
compound mixed therewith was treated three times under a condition
at an air pressure of 0.5 MPa by using a nanomizer (NM2000-AR,
manufactured by Yoshida Kikai Co., Ltd.), thereby thoroughly
dispersing and mixing the molybdenum compound and the silica
particles.
[0221] Subsequently, this molybdenum compound-dispersed silica
slurry was gradually added to a slurry of (K) an inorganic filler
while stirring, and after the whole amount was completely added,
the components were stirred for one hour until the whole became
homogenous.
[0222] Thereafter, this slurry was added to a resin varnish which
had been prepared by dissolving (J) a thermosetting resin and a
curing agent in an organic solvent, while stirring, to which was
then further added a curing accelerator, and the components were
stirred for one hour until the whole became homogenous, thereby
preparing a resin composition varnish.
[0223] A solid content concentration of the resin composition
varnishes of Comparative Example 11 was 70% by mass.
[0224] Each of the resin composition varnishes manufactured in the
foregoing Examples and Comparative Examples was impregnated and
coated on an E-glass cloth (WEA116E, manufactured by Nitto Boseki
Co., Ltd.) having a thickness of 0.1 mm, followed by heating for
drying at 160.degree. C. for 5 minutes, thereby obtaining a prepreg
having a content of the resin composition of 48% by mass. Four
sheets of this prepreg were superimposed, and an electrolytic
copper foil having a thickness of 12 .mu.m was disposed on the top
and bottom, followed by vacuum pressing under a pressure of 3.8 MPa
at a temperature of 185.degree. C. for 90 minutes, thereby
obtaining a copper clad laminate plate.
[0225] By using the thus obtained resin composition varnish and
copper clad laminate plate, precipitation properties of the resin
composition varnish, the presence or absence of an aggregate in the
varnish, drilling processability of the copper clad laminate plate,
and a coefficient of thermal expansion were measured and evaluated
by the following methods. The evaluation results are summarized in
Table 7.
(1) Evaluation of Precipitation Properties of Resin Composition
Varnish:
[0226] 500 cm.sup.3 of the resin composition varnish was taken in a
glass-made settling tube having a diameter of 5 cm and a length of
35 cm and allowed to stand at room temperature of 25.degree. C.,
and a time until a precipitate accumulated on the bottom of the
settling tube was measured, thereby evaluating the precipitation
properties.
(2) Evaluation of Presence or Absence of Aggregate in Resin
Composition Varnish:
[0227] 100 cm.sup.3 of the resin composition varnish was taken in a
flask, to which was then added 400 cm.sup.3 of an organic solvent
the same as that used in the varnish, and the mixture was well
shaken. This dilute varnish was filtered through a nylon mesh
having an opening of 20 .mu.m, and whether or not a residue
remained on the mesh was visually confirmed, thereby evaluating the
presence or absence of an aggregate.
(3) Evaluation of Drilling Processability of Copper Clad Laminate
Plate:
[0228] Two sheets of a copper clad laminate plate were
superimposed; an aluminum foil having a thickness of 0.15 mm was
disposed thereabove, whereas a paper phenol board having a
thickness of 1.5 mm was disposed thereunder; 6,000 holes were
drilled with a drill .phi.0.2 mm by using a drilling machine
[ND-1V212, manufactured by Hitachi Via Mechanics, Ltd.] under a
condition at a rotation number of 160 krpm and a feed rate of 2
m/min under a chip load of 12.5 .mu.m/rev; and a wear amount of
drill cutting blade and hole registration accuracy were measured by
the following methods, thereby evaluating the drilling
processability.
(a) Wear Amount of Drill Cutting Blade:
[0229] A drilling cutting blade portion before and after drilling
was observed from the drill central axis by using a scanning
electron microscope (S-4700, manufactured by Hitachi, Ltd.), and a
wear retreat amount of cutting blade edge was measured and defined
as the wear amount of drill cutting blade.
(b) Hole Registration Accuracy:
[0230] Of the two-ply copper clad laminate plates, a registration
deviation amount of holes of the lower side (drill exit side) of
the second sheet was measured using a hole registration accuracy
analyzer (HT-1AM, manufactured by Hitachi Via Mechanics, Ltd.), and
average+3a (a: standard deviation) of registration deviation
amounts of the 4,001st to 6,000th hit holes was calculated and
defined as the hole registration accuracy.
(4) Measurement of Coefficient of Thermal Expansion of Copper Clad
Laminate Plate:
[0231] After removing a copper foil of a copper clad laminate plate
with an etching liquid, the resulting laminate plate was cut into a
size of 5 mm square, thereby fabricating a specimen. A coefficient
of thermal expansion of this specimen in the machine direction
(longitudinal direction of the glass cloth) at from 50.degree. C.
to 120.degree. C. was measured at a temperature rising rate of
10.degree. C./min by using a TMA test apparatus (TMA2940,
manufactured by TA Instruments).
TABLE-US-00006 TABLE 6 Comparative Comparative Comparative
Comparative Component Example 8 Example 9 Example 8 Example 9
Example 10 Example 11 (H) Slurry having H-1 20 20 silica particle
H-2 30 dispersed in H-3 12 organic solvent H-4 60 (I) Molybdenum
I-1 23.4 23.4 23.4 23.4 compound I-2 23.9 I-3 19.0 (J)
Thermosetting resin 100 100 100 100 100 100 Curing agent 63 63 63
63 63 63 Curing accelerator 1 1 1 1 1 1 Organic solvent 69 59 77 29
79 69 (K) Inorganic filler 402 (47) 402 (47) 402 (47) 402 (47) 406
(47.5) 402 (47) Unit: Parts by mass (however, % by volume in the
parenthesis)
[0232] Table 6 shows a blend regarding the resin composition
varnish manufactured by the manufacturing method of each of the
Examples and Comparative Examples, as expressed in terms of parts
by mass in the case where the blending amount of the thermosetting
resin (J) is defined as 100 parts by mass. However, with respect to
each of the slurry having the silica particle (H) dispersed in an
organic solvent and the inorganic filler (K), the blending amount
including the organic solvent contained therein is shown. Of these,
with respect to (K), a value of % by volume of the inorganic filler
in the case where the whole of the resin composition exclusive of
the organic solvent contained in the resin composition varnish is
defined 100% by volume was also expressed in each of the
parentheses. Also, with respect to the molybdenum compound (I), in
the case of using a particle in which the molybdenum compound is
supported by other substance, a blending amount as the supported
particle but not the molybdenum compound alone is shown.
[0233] Also, the following materials were used as the respective
components in Table 6.
(H) Silica slurry H-1: Slurry in which silica having an average
particle size of 0.05 .mu.m and a specific surface area of 55
m.sup.2/g is dispersed in a silica blending amount of 30% by mass
in propylene glycol monomethyl ether (ADMANANO, manufactured by
Admatechs Company Limited) (H) Silica slurry H-2: Slurry in which
silica having an average particle size of 0.025 .mu.m and a
specific surface area of 110 m.sup.2/g is dispersed in a silica
blending amount of 20% by mass in propylene glycol monomethyl ether
(ADMANANO, manufactured by Admatechs Company Limited) (H) Silica
slurry H-3: Slurry in which silica (SO-25R, manufactured by
Admatechs Company Limited) having an average particle size of 0.5
.mu.m and a specific surface area of 7 m.sup.2/g is dispersed in a
silica blending amount of 50% by mass in propylene glycol
monomethyl ether (H) Silica slurry H-4: Slurry in which silica
(380, manufactured by Nippon Aerosil Co., Ltd.) having an average
particle size of 0.05 .mu.m and a specific surface area of 380
m.sup.2/g is dispersed in a silica blending amount of 10% by mass
in propylene glycol monomethyl ether (I) Molybdenum compound I-1:
Zinc molybdate (a reagent, manufactured by Strem Chemicals Inc.)
(I) Molybdenum compound I-2: Calcium molybdate (a reagent,
manufactured by Strem Chemicals Inc.) (I) Molybdenum compound I-3:
Zinc molybdate-supported talc, zinc molybdate content: 10% by mass
(KEMIGARD 911C, manufactured by Sherwin-Williams Company) (J)
Thermosetting resin: Phenol novolak type epoxy resin (EPICLON
N-770, manufactured by DIC Corporation) Curing agent: Cresol
novolak type phenol resin (PHENOLITE KA-1165, manufactured by DIC
Corporation) Curing accelerator: 2-Ethyl-4-methyl imidazole
[(2E4MI, manufactured by Shikoku Chemicals Corporation) Organic
solvent: Propylene glycol monomethyl ether (manufacture by Godo
Co., Ltd.) (K) Inorganic filler: Fused spherical silica slurry,
average particle size: 0.5 .mu.m, specific surface area: 7
m.sup.2/g, silica blending amount: 70% by mass (SC2050-KC,
manufactured by Admatechs Company Limited)
TABLE-US-00007 TABLE 7 Comparative Comparative Comparative
Comparative Item Unit Example 8 Example 9 Example 8 Example 9
Example 10 Example 11 Precipitation properties h 72 84 12 84 48 72
Aggregate -- No No No Yes Yes Yes Drilling Wear amount of .mu.m 10
9 12 10 12 10 processability drill cutting blade Hole registration
.mu.m 30 31 30 34 35 31 accuracy Coefficient of thermal expansion
10.sup.-6/ 11.5 11.7 11.4 12.0 11.3 11.5 .degree. C.
[0234] As is clear from Table 7, the Examples of the present
invention are excellent in all of the issues regarding the
precipitation properties and presence or absence of an aggregate of
the resin composition varnish, and the drilling processability and
coefficient of thermal expansion of the copper clad laminate
plate.
[0235] On the other hand, in Comparative Example 8, since the
silica particle in the slurry (H) is large in the average particle
size and small in the specific surface area, the precipitation
properties of the resin composition varnish are significantly
inferior.
[0236] Also, in Comparative Example 9, since the silica particle in
the slurry (H) is large in the specific surface area, the aggregate
remains in the resin composition varnish, and the hole registration
accuracy is slightly deteriorated. In Comparative Example 10, since
the molybdenum compound-supported talc is added directly to the
resin varnish, the precipitation properties of the resin
composition varnish are inferior, and the aggregate remains.
Furthermore, the hole registration accuracy is slightly
deteriorated. In Comparative Example 11, since the molybdenum
compound-dispersed silica slurry is added to the inorganic filler
slurry and then added to the resin varnish, the aggregate remains
in the resin composition varnish.
[0237] Incidentally, if a printed wiring board is fabricated in a
state in which the aggregate remains in the resin composition
varnish, there is a concern that abnormal deposition of a plating
to be caused due to molybdenum, or the like is easily generated
during the manufacture, thereby impairing the reliability as an
electronic appliance, and therefore, such is not preferable.
[0238] In the light of the above, according to the present
invention, a resin composition varnish in which the precipitation
or aggregation of a molybdenum compound hardly occurs can be
manufactured, and by using this, a prepreg and a laminate plate,
each of which has a low coefficient of thermal expansion and high
drilling processability and which is suitable for semi-conductor
packages or printed wiring boards, can be obtained.
INDUSTRIAL APPLICABILITY
[0239] The thermosetting resin composition of the present invention
is especially low in thermal expansion properties and excellent in
drilling processability and heat resistance, and it is suitably
used for electronic components, etc. Also, according to the
laminate plate for wiring boards of the present invention, it is
possible to provide a laminate plate for wiring boards, which is
very excellent in drilling processability at the time of
fabricating a wiring board and which also has favorable electrical
insulating properties and low thermal expansion properties.
Furthermore, according to the varnish obtained by the method for
manufacturing a resin composition varnish of the present invention,
it is possible to provide a prepreg and a laminate plate each
having high drilling processability.
* * * * *