U.S. patent application number 10/735708 was filed with the patent office on 2004-07-08 for electronic device packaging and curable resin composition.
This patent application is currently assigned to Ube Industries, Ltd.. Invention is credited to Ishikawa, Seiji, Kinouchi, Masayuki, Matsui, Yuji, Naiki, Masahiro, Tanaka, Yoshiki.
Application Number | 20040132888 10/735708 |
Document ID | / |
Family ID | 32686316 |
Filed Date | 2004-07-08 |
United States Patent
Application |
20040132888 |
Kind Code |
A1 |
Naiki, Masahiro ; et
al. |
July 8, 2004 |
Electronic device packaging and curable resin composition
Abstract
A process for packaging an electronic device employs an
insulating protective resin layer produced from one or more of the
resin compositions: (1) 100 parts of an organic solvent-soluble
resin having a polysiloxane skeleton and a polar group, 0.5 to 30
parts of an epoxy compound having an epoxy equivalent of more than
800, and an organic solvent; (2) 100 parts of an organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group, 0.1 to 10 parts of an epoxy compound having an epoxy
equivalent of 100 to 800, 2 to 30 weight parts of a polyvalent
isocyanate compound, and an organic solvent; and (3) 100 parts of
an organic solvent-soluble resin having a polysiloxane skeleton and
a polar group, 0.1 to 20 parts of an epoxy compound having an epoxy
equivalent of more than 800, 2 to 30 parts of a polyvalent
isocyanate compound, and an organic solvent.
Inventors: |
Naiki, Masahiro; (Yamaguchi,
JP) ; Kinouchi, Masayuki; (Yamaguchi, JP) ;
Ishikawa, Seiji; (Chiba, JP) ; Matsui, Yuji;
(Yamaguchi, JP) ; Tanaka, Yoshiki; (Yamaguchi,
JP) |
Correspondence
Address: |
NIXON PEABODY, LLP
401 9TH STREET, NW
SUITE 900
WASINGTON
DC
20004-2128
US
|
Assignee: |
Ube Industries, Ltd.
Ube-shi
JP
|
Family ID: |
32686316 |
Appl. No.: |
10/735708 |
Filed: |
December 16, 2003 |
Current U.S.
Class: |
524/449 ;
257/E23.12; 427/402; 427/96.2; 427/98.5; 438/127; 524/492 |
Current CPC
Class: |
H05K 2201/0162 20130101;
Y10T 29/49171 20150115; Y10T 29/49224 20150115; H05K 3/285
20130101; H01L 23/296 20130101; H05K 3/3452 20130101; H01L
2224/16225 20130101; H01L 2924/3011 20130101; H01L 2924/00014
20130101; H01L 2924/00014 20130101; H01L 2224/0401 20130101 |
Class at
Publication: |
524/449 ;
427/096; 427/402; 524/492 |
International
Class: |
B05D 005/12; B05D
001/36; C08K 003/34 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 16, 2002 |
JP |
2002-363399 |
Jan 29, 2003 |
JP |
2003-020936 |
Jul 15, 2003 |
JP |
2003-197050 |
Oct 8, 2003 |
JP |
2003-349227 |
Oct 23, 2003 |
JP |
2003-363187 |
Claims
What is claimed is:
1. In a process for packaging an electronic device comprising the
steps of: preparing a printed wiring board which has wiring copper
layers coated with a metal layer comprising a metal other than
copper; coating the metal layer with an insulating protective resin
layer, keeping an area for mounting an electronic device exposed;
mounting the electronic device on the exposed area via an
electroconductive material; and coating the mounted electronic
device and a portion of the insulating protective resin layer with
an encapsulant; an improvement in which the insulating protective
resin layer is produced by employing at least one of the following
resin compositions (1) to (3): (1) a resin composition comprising
100 weight parts of an organic solvent-soluble resin having a
polysiloxane skeleton and a polar group, 0.5 to 30 weight parts of
an epoxy compound having an epoxy equivalent of more than 800, and
an organic solvent; (2) a resin composition comprising 100 weight
parts of an organic solvent-soluble resin having a polysiloxane
skeleton and a polar group, 0.1 to 10 weight parts of an epoxy
compound having an epoxy equivalent of 100 to 800, 2 to 30 weight
parts of a polyvalent isocyanate compound, and an organic solvent;
and (3) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.1 to 20 weight parts of an epoxy compound having an
epoxy equivalent of more than 800, 2 to 30 weight parts of a
polyvalent isocyanate compound, and an organic solvent.
2. The process of claim 1, wherein the metal layer comprises
tin.
3. The process of claim 1, wherein the organic solvent-soluble
resin is an organic solvent-soluble polyimide-siloxane.
4. The process of claim 3, wherein the organic solvent-soluble
polyimide siloxane is produced by a reaction of a tetracarboxylic
acid compound with a diamine compound comprising 30 to 95 mol. % of
a diaminopolysiloxane compound, 0.5 to 40 mol. % of an aromatic
diamine compound having a polar group on an aromatic ring thereof
and 0 to 69.5 mol. % of an diamine compound other than the aromatic
diamine compound.
5. The process of claim 1, wherein the resin composition contains a
curing catalyst.
6. The process of claim 1, wherein the resin composition contains a
filler.
7. The process of claim 1, wherein the resin composition is curable
at a temperature of lower than 130.degree. C.
8. A resin composition comprising a combination of 100 weight parts
of an organic solvent-soluble resin having a polysiloxane skeleton
and a polar group, 0.1 to 10 weight parts of an epoxy compound
having an epoxy equivalent of 100 to 800, 2 to 30 weight parts of a
polyvalent isocyanate compound, and an organic solvent, or a
combination of 100 weight parts of an organic solvent-soluble resin
having a polysiloxane skeleton and a polar group, 0.1 to 20 weight
parts of an epoxy compound having an epoxy equivalent of more than
800, 2 to 30 weight parts of a polyvalent isocyanate compound, and
an organic solvent.
9. The resin composition of claim 8, wherein the organic
solvent-soluble resin is an organic solvent-soluble
polyimide-siloxane.
10. The resin composition of claim 9, wherein the organic
solvent-soluble polyimide siloxane is produced by a reaction of a
tetracarboxylic acid compound with a diamine compound comprising 30
to 95 mol. % of a diaminopolysiloxane compound, 0.5 to 40 mol. % of
an aromatic diamine compound having a polar group on an aromatic
ring thereof and 0 to 69.5 mol. % of an diamine compound other than
the aromatic diamine compound.
11. The resin composition of claim 8, which further contains a
curing catalyst.
12. The resin composition of claim 8, which further contains a
filler.
13. The resin composition of claim 8, which is curable at a
temperature of lower than 130.degree. C.
14. A cured resin material which is produced by curing at least one
of the following resin compositions (1) to (3) for producing: (1) a
resin composition comprising 100 weight parts of an organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group, 0.5 to 30 weight parts of an epoxy compound having an epoxy
equivalent of more than 800, and an organic solvent; (2) a resin
composition comprising 100 weight parts of an organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group, 0.1 to 10 weight parts of an epoxy compound having an epoxy
equivalent of 100 to 800, 2 to 30 weight parts of a polyvalent
isocyanate compound, and an organic solvent; and (3) a resin
composition comprising 100 weight parts of an organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group, 0.1 to 20 weight parts of an epoxy compound having an epoxy
equivalent of more than 800, 2 to 30 weight parts of a polyvalent
isocyanate compound, and an organic solvent, and which shows no
glass transition temperature of higher than 160.degree. C.
15. The cured resin material of claim 14, wherein the organic
solvent-soluble resin is an organic solvent-soluble
polyimide-siloxane.
16. The cured resin material of claim 15, wherein the organic
solvent-soluble polyimide siloxane is produced by a reaction of a
tetracarboxylic acid compound with a diamine compound comprising 30
to 95 mol. % of a diaminopolysiloxane compound, 0.5 to 40 mol. % of
an aromatic diamine compound having a polar group on an aromatic
ring thereof and 0 to 69.5 mol. % of an diamine compound other than
the aromatic diamine compound.
17. The cured resin material of claim 14, which further contains a
curing catalyst.
18. The cured resin material of claim 14, which further contains a
filler.
Description
FIELD OF THE INVENTION
[0001] This invention relates to an improvement of a process for
packaging an electronic device, and a curable resin composition
favorably employable for the electronic device packaging
process.
BACKGROUND OF THE INVENTION
[0002] Heretofore, there are known a number of systems for
packaging an electronic device such as TCP (tape carrier package)
and COF (chip on film). The COF is paid attention because the COF
is favorably employable for packaging an electronic device with an
increased density.
[0003] The conventional COF is illustrated in FIG. 1. The process
for packaging an electronic device according to the conventional
COF system is performed by the following steps:
[0004] preparing a printed wiring board 1 which has wiring copper
layers 2 coated with an insulating protective resin layer 4,
keeping an area for mounting an electronic device exposed;
[0005] plating the exposed area with tin to produce a tin layer
3;
[0006] mounting the electronic device 6 on the tin-plated area via
an electroconductive material 5; and
[0007] coating the mounted electronic device 6 and an edge of the
insulating protective resin layer 4 with an encapsulant 7.
[0008] It is known that the insulating protective resin layer can
be favorably produced by coating the wiring copper layers with a
heat curable resin composition comprising an organic
solvent-soluble resin having a polysiloxane skeleton (or
polysiloxane chain) and a polar group, a heat curable compound and
an organic solvent, and heating the coated resin composition. The
heating is generally carried out at approx. 160.degree. C.
[0009] U.S. Pat. No. 5,252,703 describes that a heat curable resin
composition comprising 100 weight parts of a polyimide-siloxane, 1
to 50 weight parts of an epoxy resin, and an organic solvent can be
employed for preparing an insulating protective layer on a flexible
wiring board.
[0010] U.S. Pat. No. 6,461,738 describes a heat curable resin
composition comprising 100 weight parts of a polyimide-siloxane, 2
to 40 weight parts of a polyvalent isocyanate, and an organic
solvent can be employed for preparing an insulating protective
layer on a flexible wiring board.
[0011] It has been recently noted that the conventional COF has a
problem that disturbs packaging of an electronic device with a more
increased density. The problem is that the plated tin enters
between the wiring copper layer and the insulating protective layer
and then reacts with copper in the wiring copper layer, resulting
in production of a damaged portion in the wiring copper layer. The
production of the damage portion in the wiring copper layer is
particularly troublesome when the wiring copper layer is made
thinner to further increase the packaging density.
[0012] In order to obviate the above-mentioned problem in the
conventional COF packaging, an improved COF packaging system has
been developed. The improved COF packaging system is described
below, referring to FIG. 2.
[0013] The improved COF packaging system comprises the steps
of:
[0014] preparing a printed wiring board 1 which has wiring copper
layers 2 coated with a metal layer 3 comprising a metal (e.g., tin)
other than copper;
[0015] plating the metal layer 3 with an insulating protective
resin layer 4, keeping an area for mounting an electronic device
exposed;
[0016] mounting the electronic device 6 on the exposed area via an
electroconductive material 5; and
[0017] coating the mounted electronic device 6 and a portion of the
insulating protective resin layer 4 with an encapsulant 7.
[0018] The improved COF packaging system is favorably employable
for packaging an electronic device with a more increased density,
because the electronic device can be mounted on a printed wiring
board having a very thin wiring layer with no trouble of damage of
the wiring copper layer.
[0019] However, there arises a new problem in that the heat curable
resin composition comprising a polyimide-siloxane, a polyvalent
isocyanate, and an organic solvent can be cured only at a high
temperature such as approx. 160.degree. C. and, at that
temperature, tin of the plated tin layer rapidly diffuses into
copper in the wiring copper layer to produce a tin-copper alloy.
The tin-copper alloy is not appropriate because the tin-copper
alloy formed on the exposed tin layer cannot firmly fix the
electronic device via the electroconductive material (typically,
gold).
[0020] There also is a problem in that the insulating protective
resin layer prepared from a heat curable resin composition
comprising a polyimide-siloxane, an epoxy resin, and an organic
solvent has poor affinity and poor compatibility with the
encapsulant.
SUMMARY OF THE INVENTION
[0021] Accordingly, it is an object of the present invention
[0022] Accordingly, it is an object of the present invention to
provide a resin composition which is curable at a temperature of
130.degree. C. or lower, to produce an insulating protective resin
layer having satisfactory affinity and compatibility with an
encapsulant.
[0023] The present invention resides in an improvement in a process
for packaging an electronic device comprising the steps of:
[0024] preparing a printed wiring board which has wiring copper
layers coated with a metal layer comprising a metal (e.g., tin)
other than copper;
[0025] coating the metal layer with an insulating protective resin
layer, keeping an area for mounting an electronic device
exposed;
[0026] mounting the electronic device on the exposed area via an
electroconductive material; and
[0027] coating the mounted electronic device and a portion of the
insulating protective resin layer with an encapsulant (including an
underfill material);
[0028] in which the insulating protective resin layer is produced
by employing at least one of the following curable resin
compositions (1) to (3):
[0029] (1) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.5 to 30 weight parts of an epoxy compound having an
epoxy equivalent of more than 800, and an organic solvent;
[0030] (2) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.1 to 10 weight parts of an epoxy compound having an
epoxy equivalent of 100 to 800, 2 to 30 weight parts of a
polyvalent isocyanate compound, and an organic solvent; and
[0031] (3) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.1 to 20 weight parts of an epoxy compound having an
epoxy equivalent of more than 800, 2 to 30 weight parts of a
polyvalent isocyanate compound, and an organic solvent.
[0032] The invention further resides in a curable resin composition
comprising a combination of 100 weight parts of an organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group, 0.1 to 10 weight parts of an epoxy compound having an epoxy
equivalent of 100 to 800, 2 to 30 weight parts of a polyvalent
isocyanate compound, and an organic solvent, or a combination of
100 weight parts of an organic solvent-soluble resin having a
polysiloxane skeleton and a polar group, 0.1 to 20 weight parts of
an epoxy compound having an epoxy equivalent of more than 800, 2 to
30 weight parts of a polyvalent isocyanate compound, and an organic
solvent.
[0033] The invention furthermore resides in a cured resin material
which is produced by curing at least one of the following curable
resin compositions (1) to (3):
[0034] (1) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.5 to 30 weight parts of an epoxy compound having an
epoxy equivalent of more than 800, and an organic solvent;
[0035] (2) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.1 to 10 weight parts of an epoxy compound having an
epoxy equivalent of 100 to 800, 2 to 30 weight parts of a
polyvalent isocyanate compound, and an organic solvent; and
[0036] (3) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.1 to 20 weight parts of an epoxy compound having an
epoxy equivalent of more than 800, 2 to 30 weight parts of a
polyvalent isocyanate compound, and an organic solvent,
[0037] and which shows no glass transition temperature of higher
than 160.degree. C.
[0038] In the invention, the organic solvent-soluble resin
preferably is an organic solvent-soluble polyimide-siloxane. The
organic solvent-soluble polyimide siloxane is preferably produced
by a reaction of a tetracarboxylic acid compound with a diamine
compound and comprises 30 to 95 mol. % of a diaminopolysiloxane
compound, 0.5 to 40 mol. % of an aromatic diamine compound having a
polar group on an aromatic ring thereof and 0 to 69.5 mol. % of an
diamine compound other than the aromatic diamine compound.
[0039] The curable resin composition preferably contains a curing
catalyst and a filler.
[0040] The curable resin composition preferably is curable at a
temperature of lower than 130.degree. C.
BRIEF DESCRIPTION OF DRAWINGS
[0041] FIG. 1 illustrates a conventional chip on film (COF)
packaging.
[0042] FIG. 2 illustrates an improved chip on film (COF)
packaging.
[0043] FIG. 3 illustrates glass transition temperatures of a cured
resin composition of the invention (Example 1) which are observed
on a curve of loss tangent (tan .delta.) against a temperature
increase.
[0044] FIG. 4 illustrates glass transition temperatures of a cured
resin composition of the invention (Example 7) which are observed
on a curve of loss tangent (tan .delta.) against a temperature
increase.
[0045] FIG. 5 illustrates glass transition temperatures of a cured
known resin composition (Comparison Example 1) which are observed
on a curve of loss tangent (tan .delta.) against a temperature
increase.
[0046] FIG. 6 illustrates glass transition temperatures of a cured
known resin composition (Comparison Example 3) which are observed
on a curve of loss tangent (tan .delta.) against a temperature
increase.
DETAILED DESCRIPTION OF THE INVENTION
[0047] The present invention provides a curable resin composition
that is favorably employable for packaging an electronic device
according to COF system. The resin composition is one of the
following resin compositions (1) to (3):
[0048] (1) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.5 to 30 weight parts, preferably 0.5 to 20 weight
parts, of an epoxy compound having an epoxy equivalent of more than
800, and an organic solvent;
[0049] (2) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.1 to 10 weight parts, preferably 0.1 to 7 weight
parts, of an epoxy compound having an epoxy equivalent of 100 to
800, 2 to 30 weight parts of a polyvalent isocyanate compound, and
an organic solvent; and
[0050] (3) a resin composition comprising 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group, 0.1 to 20 weight parts, preferably 0.5 to 15 weight
parts, of an epoxy compound having an epoxy equivalent of more than
800, 2 to 30 weight parts of a polyvalent isocyanate compound, and
an organic solvent.
[0051] [Organic Solvent-Soluble Resin Having a Polysiloxane
Skeleton and a Polar Group]
[0052] The organic solvent-soluble resin has a polysiloxane
skeleton and a polar group. The polar group is capable of reacting
with an epoxy group of the epoxy compound and/or an isocyanate
group of the polyvalent isocyanate compound. The organic
solvent-soluble resin preferably has in its skeleton a rigid
segment such as a benzene ring or an imide ring and a cohesive
segment such as an amide bonding or a urethane bonding in addition
to the flexible polysiloxane skeleton. Preferred is a
polyimide-siloxane compound.
[0053] The polyimide-siloxane is preferably produced by a reaction
of a tetracarboxylic acid compound with a diamine compound in
approximately equimolar amounts. The diamine compound preferably
comprises 30 to 95 mol. % (preferably 50 to 95 mol. %, more
preferably 60 to 95 mol. %) of a diaminopolysiloxane compound, 0.5
to 40 mol. % of an aromatic diamine compound having a polar group
on an aromatic ring thereof, and 0 to 69.5 mol. % of a diamine
compound other than the aromatic diamine compound having a polar
group on an aromatic ring thereof.
[0054] Examples of the tetracarboxylic acid compounds include
aromatic tetracarboxylic acids such as
2,3,3',4'-biphenyltetracarboxylic acid,
3,3',4,4'-biphenyltetracarboxylic acid,
3,3',4,4'-diphenylethertetracarbo- xylic acid,
3,3',4,4'-diphenylsulfonetetracarboxylic acid,
3,3',4,4'-benzophenonetetracarboxylic acid,
2,2-bis(3,4-benzenedicarboxyl- ic acid)hexafluoropropane,
pyromellitic acid, 1,4-bis(3,4-benzenedicarboxy- lic acid)benzene,
2,2-bis[4-(3,4-phenoxydicarboxylic acid)phenyl]propane,
2,3,6,7-naphthalenetetracarboxylic acid,
1,2,5,6-naphthalenetetracarboxyl- ic acid,
1,2,4,5-naphthalnetetracarboxylic acid, 1,4,5,8-naphthalenetetrac-
arboxylic acid, and 1,1-bis(2,3-dicarboxyphenyl)ethane; alicyclic
tetracarboxylic acids such as cyclopentanetetracarboxylic acid,
1,2,4,5-cyclohexanetetracarboxylic acid, and
3-methyl-4-cyclohexene-1,2,4- ,5-tetracarboxylic acid; and their
dianhydrides and esters.
[0055] The diaminopolysiloxane compound preferably has the
following formula (1): 1
[0056] in which two R.sub.1 independently represents a divalent
hydrocarbyl group or a divalent aromatic group, four R.sub.2
independently represents a monovalent hydrocarbyl group or a
monovalent aromatic group, n1 represents an integer of 3 to 50.
[0057] Examples of the diaminopolysiloxane compounds of the formula
(1) include .alpha., .omega.-bis(2-aminoethyl)polydimethylsiloxane,
.alpha.,.omega.-bis(3-aminopropyl)polydimethylsiloxane,
.alpha.,.omega.-bis(4-aminophenyl)polydimethylsiloxane,
.alpha.,.omega.-bis(4-amino-3-methylphenyl)polydimethylsiloxane,
.alpha.,.omega.-bis(3-aminopropyl)polydiphenylsiloxane, and
.alpha.,.omega.-bis(4-amino-butyl)polydimethylsiloxane.
[0058] The aromatic diamine compound having a polar group on an
aromatic ring thereof preferably has the following formula (2):
2
[0059] in which X and Y independently represents a single bond,
CH.sub.2, C(CH.sub.3).sub.2, C(CF.sub.3).sub.2, O, a benzene ring,
or SO.sub.2; r1 is COOH or OH; n2 is 1 or 2; and n3 and n4
independently is 0, 1 or 2, under such condition as
n3+n4.noteq.0.
[0060] Representative examples of the aromatic diamine compounds of
the formula (2) are aromatic diamine compounds having an OH group
on an aromatic ring thereof or aromatic diamine compounds having a
COOH group on an aromatic ring thereof.
[0061] Examples of the aromatic diamine compounds having an OH
group on an aromatic ring thereof include diaminophenol Compounds
such as 2,4-diaminophenol; hydroxybiphenyl compounds such as
3,3'-diamino-4,4'-dihydroxybiphenyl,
4,4'-diamino-3,3'-dihydroxybiphenyl,
4,4'-diamino-2,2'-dihydroxybiphenyl, and
4,4'-diamino-2,2',5,5'-tetrahydr- oxybiphenyl;
hydroxydiphenylalkane compounds such as
3,3'-diamino-4,4'-dihydroxydiphenylmethane,
4,4'-diamino-3,3'-dihydroxydi- phenylmethane,
4,4'-diamino-2,2'-dihydroxydiphenylmethane,
2,2-bis(3-amino-4-hydroxyphenyl)propane,
2,2-bis(4-amino-3-hydroxyphenyl)- propane,
2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and
4,4'-diamino-2,2',5,5'-tetrahydroxydiphenylmethane; hydroxydiphenyl
ether compounds such as 3,3'-diamino-4,4'-dihydroxydiphenyl ether,
4,4'-diamino-3,3'-dihydroxydiphenyl ether,
4,4'-diamino-2,3'-dihydroxydip- henyl ether, and
4,4'-diamino-2,2',5,5'-tetrahydroxydiphenyl ether;
hydroxydiphenylsulfone compounds such as
3,3'-diamino-4,4'-dihydroxydiphe- nylsulfone,
4,4'-diamino-3,3'-dihydroxydiphenylsulfone,
4,4'-diamino-2,2'-dihydroxydiphenylsulfone, and
4,4'-diamino-2,2',5,5'-te- trahydroxydiphenylsulfone;
bis(hydroxyphenoxyphenyl)alkane compounds such as
2,2-bis[4-(4-amino-3-hydroxyphenoxy)phenyl]propane;
bis(hydroxyphenoxy)biphenyl compounds such as
4,4-bis(4-amino-3-hydroxyph- enoxy)biphenyl; and
bis(hydroxyphenoxyphenyl)sulfone compounds such as
2,2-bis[4-(4-amino-3-hydroxyphenoxy)phenyl]sulfone.
[0062] Examples of the aromatic diamine compounds having a COOH
group on an aromatic ring thereof include benzene carboxylic acid
compounds such as 3,5-diaminobenzoic acid and 2,4-diaminobenzoic
acid; carboxybiphenyl compounds such as
3,3'-diamino-4,4'-dicarboxybiphenyl,
4,4'-diamino-3,3'-dicarboxybiphenyl,
4,4'-diamino-2,2'-dicarboxybiphenyl, and
4,4'-diamino-2,2',5,5'-tetracarboxybiphenyl; carboxydiphenylalkane
compounds such as 3,3'-diamino-4,4'-dicarboxydiphenylmethane,
4,4'-diamino-3,3'-dicarboxydiphenylmethane,
4,4'-diamino-2,2'-dicarboxydi- phenylmethane,
2,2-bis(3-amino-4-carboxyphenyl)propane,
2,2-bis(4-amino-3-carboxyphenyl)propane,
2,2-bis(3-amino-4-carboxyphenyl)- hexafluoropropane, and
4,4'-diamino-2,2',5,5'-tetracarboxybiphenyl; carboxydiphenyl ether
compounds such as 3,3'-diamino-4,4'-dicarboxydiphen- yl ether,
4,4'-diamino-3,3'-dicarboxydiphenyl ether,
4,4'-diamino-2,2'-dicarboxydiphenyl ether, and
4,4'-diamino-2,2',5,5'-tet- racarboxydiphenyl ether;
carboxydiphenylsulfone compounds such as
3,3'-diamino-4,4'-dicarboxydiphenylsulfone,
4,4'-diamino-3,3'-dicarboxydi- phenylsulfone, and
4,4'-diamino-2,2',5',5'-tetracarboxydiphenylsulfone;
bis(carboxyphenoxyphenyl)alkane compounds such as
2,2-bis[4-(4-amino-3-ca- rboxyphenoxy)phenyl]propane;
bis(carboxyphenoxy)biphenyl compounds such as
4,4'-bis(4-amino-3-carboxyphenoxy)biphenyl; and
bis(carboxyphenoxyphenyl)- sulfone compounds such as
2,2-bis[4-(4-amino-3-carboxyphenoxy)phenyl]sulfo- ne.
[0063] The diamine compound other than the aromatic diamine
compound having a polar group on an aromatic ring thereof
preferably is an aromatic diamine compound having the following
formula (3): 3
[0064] in which X and Y independently represents a single bond,
CH.sub.2, C(CH.sub.3).sub.2, C(CF.sub.3).sub.2, O, a benzene ring,
or SO.sub.2; and n5 is 1 or 2.
[0065] Examples of the aromatic diamine compounds of the formula
(3) include diamine compounds having one benzene ring such as
1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, and
1,4-diamino-2,5-dihalogenobenzene; diamine compounds having two
benzene rings such as bis(4-aminophenyl)ether,
bis(3-aminophenyl)ether, bis(4-aminophenyl)sulfone,
bis(3-aminophenyl)sulfone, bis(4-aminophenyl)methane,
bis(3-aminophenyl)methane, bis(4-aminophenyl)sulfide,
bis(3-aminophenyl)sulfide, 2,2-bis(4-aminophenyl)propane,
2,2-bis(3-aminophenyl)propane,
2,2-bis(4-aminophenyl)hexafluroropropane, o-dianisidine,
o-tolidine, and tolidinesulfonic acid; diamine compounds having
three benzene rings such as 1,4-bis(4-aminophenoxy)benzene,
1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene,
1,4-bis(3-aminophenyl)benzene,
.alpha.,.alpha.'-bis(4-aminophenyl)-1,4-diisopropylbenzene, and
.alpha.,.alpha.'-bis-(4-aminophenyl)-1,3-diisopropylbenzene; and
diamine compounds having four or more benzene rings such as
2,2-bis-[4-(4-aminophenoxy)phenyl]propane,
2,2-bis[4-(4-aminophenoxy)phen- yl]hexafluoropropane,
2,2-bis[4-(4-aminophenoxy)phenyl]sulfone,
4,4'-(4,4-aminophenoxy)biphenyl, 9,9-bis(4-aminophenyl)fluorene,
and 5,10-bis(4-aminophenyl)anthracene.
[0066] An aliphatic amine compounds such as hexamethylenediamine or
diaminododecane can be employed in combination with the
above-mentioned aromatic diamine compounds.
[0067] The polyimide-siloxane compound can be prepared from the
above-mentioned compounds by known methods such as those described
in the aforementioned U.S. Pat. No. 5,252,703.
[0068] The polyimide-siloxane preferably has a high molecular
weight and has a high imidation ratio. Accordingly, the
polyimide-siloxane preferably has a logarithmic viscosity (0.5
g/100 mL of N-methyl-2-pyrrolidone, at 30.degree. C.) of 0.15 or
more, more preferably 0.16 to 2. The imidation ratio preferably is
90% or higher, more preferably 95% or more, most preferably
essentially 100%.
[0069] The polyimide-siloxane compound preferably is in the form of
a solution in an organic solvent having a solution viscosity
(measured by E-type rotary viscometer) of 1 to 10,000 poises, more
preferably 1 to 100 poises.
[0070] [Epoxy Compound]
[0071] The epoxy compound preferably has an epoxy equivalent in the
range of 100 to 4,000, more preferably 100 to 3,000. The epoxy
compounds preferably are bisphenol A-type epoxy resins, bisphenol
F-type epoxy resins, bi-functional epoxy resins, tri-functional
epoxy resins, and epoxy-modified polysiloxanes.
[0072] Examples of the epoxy compounds commercially available
include a series of compounds available under tradename of Epikote
(Japan Epoxy Resin Co., Ltd.), a series of compounds available
under tradename of EPICLON (Dainippon Ink & Chemical Industry
Co., Ltd.), MT0163 (Ciba Geigy Corp.), a series of compounds
available under tradename of DENACOL or TENALX (Nagase Chemtech
Co., Ltd.), Hycar ETBN1300.times.40 (Ube Industries, Ltd.), and
KF105 (Shin-etsu Chemical Industries Co., Ltd.).
[0073] In the curable resin compositions, an epoxy compound having
a epoxy equivalent of 100 to 800 is employed in combination with
the organic solvent-soluble resin having a polysiloxane skeleton
and a polar group and a polyvalent isocyanate compound, while an
epoxy compound having a epoxy equivalent of more than 800 can be
employed in combination with the organic solvent-soluble resin
having a polysiloxane skeleton alone or with a polyvalent
isocyanate compound.
[0074] In the former case, 100 weight parts of an organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group is used in combination with 0.1 to 10 weight parts,
preferably 0.5 to 7 weight parts, more preferably 0.5 to 5 weight
parts, of an epoxy compound having an epoxy equivalent of 100 to
800, 2 to 30 weight parts, preferably 5 to 20 weight parts, of a
polyvalent isocyanate compound, and an organic solvent.
[0075] In the latter case, 100 weight parts of the organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group is used in combination with 0.5 to 30 weight parts,
preferably 1 to 20 weight parts, more preferably 2 to 15 weight
parts, of an epoxy compound having an epoxy equivalent of more than
800, and an organic solvent. Otherwise, 100 weight parts of an
organic solvent-soluble resin having a polysiloxane skeleton and a
polar group is used in combination with 0.1 to 20 weight parts,
preferably 0.5 to 15 weight parts, more preferably 0.5 to 10 weight
parts, of an epoxy compound having an epoxy equivalent of more than
800, 2 to 30 weight parts, preferably 5 to 20 weight parts, of a
polyvalent isocyanate compound, and an organic solvent.
[0076] The epoxy compound having an epoxy equivalent of more than
800 is preferably used in combination with the organic
solvent-soluble resin having a polysiloxane skeleton and a polar
group under such condition that a molar ratio of the polar group
against the epoxy group of the epoxy compound is in the range of
1/1 to 13/1, specifically 2/1 to 12/1.
[0077] [Polyvalent Isocyanate Compound]
[0078] The polyvalent isocyanate compound has two or more
isocyanate groups in a molecule. Aliphatic, alicyclic or aromatic
diisocyanate can be employed. Examples of the diisocyanate
compounds include 1,4-tetramethylene diisocyanate,
1,5-pentamethylene diisocyanate, 1,6-hexamethylene diisocyanate,
2,2,4-trimethyl-1,6-hexamethylene diisocyanate, lysine
diisocyanate, 3-isocynatemethyl-3,5,5-trimethylcyclo- hexyl
isocyanate [=isophorone diisocyanate],
1,3-bis(isocyanatemethyl)cycl- ohexane, 4,4'-dicyclohexylmethane
diisocyanate, tolylene diisocyanate, 4,4'-diphenylmethane
diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate,
and xylylene diisocyanate.
[0079] Derivatives of the aliphatic, alicyclic and aromatic
polyvalent isocyanate compounds such as isocyanulate-modified
polyvalent isocyanate, biulet-modified polyvalent isocyanate, and
urethane-modified polyvalent isocyanate can be employed. The
polyvalent isocyanate compounds can be blocked by a blocking
agent.
[0080] Other details of the polyvalent isocyanate compounds
employable in the invention are described in the afore-mentioned
U.S. Pat. No. 6,461,738.
[0081] [Organic Solvent]
[0082] Examples of the organic solvents employable in the invention
can be nitrogen atom-containing solvents such as
N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide,
N,N-diethylformamide, N-methyl-2-pyrrolidone,
1,3-dimethyl-2-imidazolidinone, and N-methylcaprolactam; sulfur
atom-containing solvents such as dimethyl sulfoxide, diethyl
sulfoxide, dimethylsulfone, diethylsulfone, and
hexamethylsulforamide; phenol solvents such as cresol, phenol, and
xylenol; diglyme solvents such as diethylene glycol dimethyl ether
(diglyme), triethylene glycol dimethyl ether (triglyme), and
tetraglyme; acetone; acetophenone; propiophenone; ethylene glycol;
dioxane; tetrahydrofuran; and .gamma.-butylolactone. Preferred are
N-methyl-2-pyrrolidone, N,N-dimethyl sulfoxide,
N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide,
N,N-diethylacetamide, .gamma.-butylolactone, triethylene glycol
dimethyl ether, and diethylene glycol dimethyl ether.
[0083] There are no specific limitations with respect to the amount
of the organic solvent in the curable resin composition. However,
th organic solvent can be employed preferably in an amount of 60 to
200 weight parts, based on 100 weight parts of the siloxane
skeleton-containing resin.
[0084] The organic solvent can be incorporated into the curable
resin composition in the form of a solution of the polysiloxane
skeleton-containing resin in an organic solvent.
[0085] [Optionally Incorporatable Compounds]
[0086] The curable resin composition preferably contains a
dissociation catalyst and/or a curing catalyst. The dissociation
catalyst serves to dissociate the blocking agent from the blocked
polyisocyanate. The curing catalyst serves to accelerate the
crosslinking reaction between the polysiloxane skeleton-containing
resin and the epoxy compound (and further the polyvalent isocyanate
compound). The dissociation catalyst can be dibutyltin laurate or a
tertiary amine. The curing catalyst can be an imidazole compound
(e.g., 2-ethyl-4-methylimidazole), hydrazine, or a tertiary amine.
The tertiary amine is preferably incorporated. Examples of the
tertiary amines include 1,8-diazobicyclo[5,4,0]-7-undecene (DBU),
N,N-dimethylbenzylamine (DMBA), and
N,N,N',N'-tetramethylhexanediamine. The tertiary diamine can be
employed in an amount of 0.3 to 20 weight parts, preferably 0.5 to
10 weight parts, based on 100 weight parts of the polysiloxane
skeleton-containing resin.
[0087] The curable reresin composition of the invention can contain
a fine filler such as micro-powdery silica, talc, mica, barium
sulfate, or cross-linked NBR powder. The fine filler preferably has
a mean size in the range of 0.001 to 15 .mu.m, more preferably
0.005 to 10 .mu.m. The fine filler can be incorporated into the
resin composition in an amount of 20 to 150 weight parts,
preferably 40 to 125 weight parts, based on 100 weight parts the
polysiloxane skeleton-containing resin.
[0088] The curable resin composition of the invention can contain a
pigment such as a colored organic pigment or a colored inorganic
pigment.
[0089] The curable resin composition of the invention can contain a
anti-foaming agent.
[0090] [Utilization of the Curable Resin Composition]
[0091] The curable resin composition of the invention can be
employed for producing insulating resin coats in various technical
fields. The curable resin composition is particularly
advantageously employable when the curing temperature should be low
such as 130.degree. C. or lower. Accordingly, the curable resin
composition of the invention is particularly favorably employable
in the aforementioned electronic device packaging process according
to the improved COF packaging system (see FIG. 2) which comprises
the steps of:
[0092] preparing a printed wiring board 1 which has wiring copper
layers 2 coated with a metal layer 3 comprising a metal other than
copper;
[0093] coating the metal layer 3 with an insulating protective
resin layer 4, keeping an area for mounting an electronic device
exposed;
[0094] mounting the electronic device 6 on the exposed area via an
electroconductive material 5; and
[0095] coating the mounted electronic device 6 and a portion of the
insulating protective resin layer 4 with an encapsulant 7.
[0096] In the step for coating the mounted electronic device and a
portion (particularly the edge) of the insulating protective resin
layer with an encapsulant, an applied encapsulant is generally
heated to approx. 160.degree. C. for curing the encapsulant. At the
same time, the already cured insulating protective resin layer is
further hardened.
[0097] The present invention is further described by the following
examples. In the examples, the term "part(s)" means "weight
part(s)", unless otherwise indicated.
REFERENCE EXAMPLE 1
Production of Polyimide-Siloxane
[0098] In a 500 mL-volume glass flask were heated to 180.degree. C.
under stirring 58.84 g (0.2 mol) of
2,3,3',4'-biphenyltetracarboxylic dianhydride and 120 g of triglyme
(solvent) under nitrogen gas atmosphere. To the reaction mixture
were added 154.7 g (0.17 mol) of
.alpha.,.omega.-bis(3-aminopropyl)polydimethylsiloxane (amino
equivalent: 455) and 70 g of triglyme, and the resulting mixture
was further heated to 180.degree. C. for 60 minutes. To thus
obtained reaction mixture were added 8.59 g (0.03 mol) of
bis(3-carboxy-4-aminophenyl)methane and 23.4 g of triglyme, and the
resulting mixture was further heated to 180.degree. C. for 5 hours.
Thus obtained reaction mixture was filtered, to give a
polyimide-siloxane solution of .eta..sub.inh of 0.18 having a solid
content (polymer content) of 50 wt. %. The imidation ratio is
almost 100%. The obtained polyimide-siloxane solution was named
polyimide-siloxane solution A.
REFERENCE EXAMPLE 2
Production of Polyimide-Siloxane
[0099] In a 500 mL-volume glass flask were heated to 180.degree.C.
under stirring 58.84 g (0.2 mol) of
2,3,3',4'-biphenyltetracarboxylic dianhydride and 170 g of triglyme
(solvent) under nitrogen gas atmosphere. The reaction mixture were
cooled to approx. 100.degree. C., and to this were added 127.4 g
(0.14 mol) of .alpha.,.omega.-bis(3-aminop-
ropyl)polydimethylsiloxane (amino equivalent: 455) and 50 g of
triglyme, and the resulting mixture was further heated to
180.degree. C. for 60 minutes. Thus obtained reaction mixture was
cooled to room temperature, and to this were added 13.52 g (0.03
mol) of 2,2-bis[4-(4-aminophenoxy)ph- enyl]propane, 4.56 g (0.03
mol) of 3,5-diaminobenzoic acid, and 79 g of triglyme, and the
resulting mixture was further heated to 180.degree. C. for 5 hours.
Thus obtained reaction mixture was filtered, to give a
polyimide-siloxane solution of .eta..sub.inh of 0.20 having a solid
content (polymer content) of 40 wt. %. The imidation ratio is
almost 100%. The obtained polyimide-siloxane solution was named
polyimide-siloxane solution B.
EXAMPLE 1
[0100] In a glass vessel, the following components were stirred to
give a uniform polyimide-siloxane solution composition (solution
viscosity: 360 poises):
[0101] polyimide-siloxane solution A: 100 parts in terms of solid
content;
[0102] Epikote 1007 (epoxy equivalent: 2,000): 10 parts;
[0103] DBU (tertiary amine): 2 parts;
[0104] silicone antifoaming agent: 4 parts;
[0105] Aerogil 50 (micropowdery silica): 15.8 parts;
[0106] Aerogil 130 (micropowdery silica): 1.8 parts;
[0107] barium sulfate: 44 parts;
[0108] talc: 11 parts;
[0109] mica: 11 parts.
[0110] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0111] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C., and showed an electric insulation of
5.times.10.sup.13 .OMEGA..multidot.cm (volume resistance).
[0112] A polyimide-siloxane solution composition containing no
filler components was prepared and cured at 120.degree. C. to give
a cured sheet (thickness: 150 .mu.m). The cured composition was cut
to give a specimen (5 mm.times.30 mm.times.150 .mu.m). The specimen
was subjected to determination of Tg by obtaining a variation of
loss tangent (tan .delta.) depending on variation of temperature by
means of a viscoelastic analyzer RSA-II (available from Rheometric
Scientific Corp.) in tension-compression mode from the temperature
of -150.degree. C. at a frequency of 10 Hz under nitrogen stream.
The measurements were carried out by increasing the temperature
stepwise by 2.degree. C., and keeping the temperature for 30
minutes at each temperature.
[0113] The obtained curve of variation of tan .delta. is shown in
FIG. 3. The highest peak (i.e., the peak observed at the higher
temperature side, which indicates Tg) is observed at 110.degree.
C.
EXAMPLE 2
[0114] A uniform polyimide-siloxane solution composition (solution
viscosity: 340 poises) was obtained by the same procedures as those
in Example 1 except that Epikote 1007 was replaced with a
combination of 5 parts of Epikote 1007 and 5 parts of Epikote 1004
(epoxy equivalent: 900).
[0115] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0116] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 3. The highest peak (indicating
Tg) is observed at 109.degree. C.
EXAMPLE 3
[0117] A uniform polyimide-siloxane solution composition (solution
viscosity: 300 poises) was obtained by the same procedures as those
in Example 1 except that Epikote 1007 was replaced with 10 parts of
Epikote 1004 (epoxy equivalent: 900).
[0118] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0119] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C., and showed an electric insulation of
4.times.10.sup.14 .OMEGA..multidot.cm (volume resistance).
[0120] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 3. The highest peak (indicating
Tg) is observed at 105.degree. C.
EXAMPLE 4
[0121] A uniform polyimide-siloxane solution composition (solution
viscosity: 480 poises) was obtained by the same procedures as those
in Example 1 except that Epikote 1007 was replaced with 10 parts of
Epikote 1004 (epoxy equivalent: 900) and that 0.3 part of
2-ethyl-4-methylimidazo- le (curing catalyst) was added.
[0122] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0123] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C., and showed an electric insulation of
1.times.10.sup.14.OMEGA..multidot.cm (volume resistance).
[0124] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 3. The highest peak (indicating
Tg) is observed at 116.degree. C.
EXAMPLE 5
[0125] A uniform polyimide-siloxane solution composition (solution
viscosity: 480 poises) was obtained by the same procedures as those
in Example 1 except that Epikote 1007 was replaced with 13.8 parts
of Hycar ETBN1300.times.40 (epoxy equivalent: 2,770, 50% xylene
solution).
[0126] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0127] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C., and showed an electric insulation of
2.times.10.sup.13 .OMEGA..multidot.cm (volume resistance).
[0128] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 3. The highest peak (indicating
Tg) is observed at 121.degree. C.
EXAMPLE 6
[0129] In a glass vessel, the following components were stirred to
give a uniform polyimide-siloxane solution composition (solution
viscosity: 430 poises):
[0130] polyimide-siloxane solution B (diluted with triglyme to give
a solid content of 37%): 100 parts in terms of solid content;
[0131] Epikote 1007 (epoxy equivalent: 2,000): 10 parts;
[0132] DBU (tertiary amine): 2 parts;
[0133] silicone antifoaming agent: 4 parts;
[0134] Aerogil 50 (micropowdery silica): 14 parts;
[0135] barium sulfate: 12 parts;
[0136] talc: 40 parts;
[0137] mica: 10 parts.
[0138] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0139] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C., and showed an electric insulation of
1.times.10.sup.13 .OMEGA..multidot.cm (volume resistance).
[0140] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 3. The highest peak (indicating
Tg) is observed at 95.degree. C.
EXAMPLE 7
[0141] In a glass vessel, the following components were stirred to
give a uniform polyimide-siloxane solution composition (solution
viscosity: 300 poises):
[0142] polyimide-siloxane solution A: 100 parts in terms of solid
content;
[0143] Epikote 157S70 (epoxy equivalent: 210): 1 part;
[0144] Burnock D-550 (methyl ethyl ketoxime-blocked
1,6-hexamethylene diisocyalnate, available from Dai-nippon Ink and
Chemical Industries, Co., Ltd.): 10 parts;
[0145] DBU (tertiary amine): 5 parts;
[0146] phthalocyanine green (pigment): 1 part silicone antifoaming
agent: 2 parts;
[0147] Aerogil 50 (micropowdery silica): 18 parts;
[0148] barium sulfate: 40 parts;
[0149] talc: 20 parts;
[0150] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0151] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C. The polyimide-siloxane solution
composition was heated to 80.degree. C., for 30 min., and to
160.degree. C., for 60 min, and showed an electric insulation of
1.0.times.10.sup.15 .OMEGA..multidot.cm (volume resistance).
[0152] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg.
[0153] The obtained curve of variation of tan 6 is shown in FIG. 4.
The highest peak (indicating Tg) is observed at 129.degree. C.
EXAMPLE 8
[0154] A uniform polyimide-siloxane solution composition (solution
viscosity: 550 poises) was obtained by the same procedures as those
in Example 7 except that Burnock D-550 was replaced with 10 parts
of burnock D-500 and that DBU was used in an amount of 0.5
part.
[0155] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0156] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 127.degree. C.
EXAMPLE 9
[0157] A uniform polyimide-siloxane solution composition (solution
viscosity: 370 poises) was obtained by the same procedures as those
in Example 7 except that Barnock D-550 was replaced with 10 parts
of Takenate B-842N (methyl ethyl ketoxime-blocked
1,3-bis(isocyanatemethyl)c- yclohexane, available from
Mitsui-Takeda Chemical Co., Ltd.) and that DBU was used in an
amount of 1 part.
[0158] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0159] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 106.degree. C.
EXAMPLE 10
[0160] A uniform polyimide-siloxane solution composition (solution
viscosity: 570 poises) was obtained by the same procedures as those
in Example 7 except that Epicote 157S70 was replaced with 10 parts
of Epikote 1007 (epoxy equivalent: 2,000) and that DBU was used in
an amount of 0.5 part.
[0161] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0162] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 78.degree. C.
EXAMPLE 11
[0163] A uniform polyimide-siloxane solution composition (solution
viscosity: 330 poises) was obtained by the same procedures as those
in Example 7 except that Barnock D-550 was replaced with 10 parts
of Takenate B-815N (methyl ethyl ketoxime-blocked
4,4'-dicyclohexylmethane diisocyanate, available from Mitsui-Takeda
Chemical Co., Ltd.) and that DBU was used in an amount of 1
part.
[0164] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0165] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 107.degree. C.
EXAMPLE 12
[0166] A uniform polyimide-siloxane solution composition (solution
viscosity: 340 poises) was obtained by the same procedures as those
in Example 7 except that Epikote 157S70 was replaced with 3 parts
of KF105 (epoxy equivalent: 490, available from Sin-etsu Chemical
Industries, Co., Itd.) and that DBU was replaced with 7 parts of
N,N-dimethylbenzylamine (DMBA).
[0167] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0168] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 100.degree. C.
EXAMPLE 13
[0169] A uniform polyimide-siloxane solution composition (solution
viscosity: 300 poises) was obtained by the same procedures as those
in Example 7 except that that DBU was used in an amount of 3
parts.
[0170] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0171] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 118.degree. C.
EXAMPLE 14
[0172] A uniform polyimide-siloxane solution composition (solution
viscosity: 480 poises) was obtained by the same procedures as those
in Example 7 except that Barnock D500 was used in an amount of 10
parts, that Epikote 157S70 was replaced with 1 part of Epikote
828EL (epoxy equivalent: 190), and that DBU was used in an amount
of 0.5 part.
[0173] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0174] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C. The polyimide-siloxane solution
composition was heated to 80.degree. C., for 30 min., and to
160.degree. C., for 60 min, and showed an electric insulation of
2.0.times.10.sup.14 .OMEGA..multidot.cm (volume resistance).
[0175] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 90.degree. C.
EXAMPLE 15
[0176] A uniform polyimide-siloxane solution composition (solution
viscosity: 740 poises) was obtained by the same procedures as those
in Example 7 except that Barnock D500 was used in an amount of 10
parts, that Epikote 157S70 was replaced with 10 parts of Epikote
1007 (epoxy equivalent: 2,000), and that DBU was used in an amount
of 0.5 part.
[0177] The polyimide-siloxane solution composition showed little
viscosity change after keeping at approx. 5.degree. C. for 2 weeks
and can be printing by screen-printing procedure.
[0178] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C. The polyimide-siloxane solution
composition was heated to 80.degree. C., for 30 min., and to
160.degree. C., for 60 min, and showed an electric insulation of
2.0.times.10.sup.14 .OMEGA..multidot.cm (volume resistance).
[0179] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is similar to that of FIG. 4. The highest peak (indicating
Tg) is observed at 111.degree. C.
COMPARISON EXAMPLE 1
[0180] A uniform polyimide-siloxane solution composition (solution
viscosity: 380 poises) was obtained by the same procedures as those
in Example 1 except that Epikote 1007 was replaced with 10 parts of
Epikote 157S70 (epoxy equivalent: 210) and that DBU was used in an
amount of 2 parts.
[0181] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C.
[0182] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is shown in FIG. 5. The highest peak (indicating Tg) is
observed at 170.degree. C. This means that the cured protective
layer is rigid and hence has no enough flexibility to closely
contact with an encapsulant when the encapsulant was heated to
160.degree. C. for curing for final packaging.
COMPARISON EXAMPLE 2
[0183] A uniform polyimide-siloxane solution composition (solution
viscosity: 270 poises) was obtained by the same procedures as those
in Example 7 except that Epikote 157S70 was not used, Barnock D550
was used in an amount of 10 parts, and that DBU was used in an
amount of 5 parts.
[0184] The polyimide-siloxane solution composition could not cured
by heating to 120.degree. C.
COMPARISON EXAMPLE 3
[0185] A uniform polyimide-siloxane solution composition (solution
viscosity: 380 poises) was obtained by the same procedures as those
in Example 7 except that Epikote 157S70 was replaced with 15 parts
of Epikote 157S70 (epoxy equivalent: 210) and that DBU was used in
an amount of 1 part.
[0186] The polyimide-siloxane solution composition was cured by
heating to 120.degree. C.
[0187] A polyimide-siloxane solution composition containing no
filler components was prepared and cured in the same manner as in
Example 1. A specimen was prepared in the same manner and subjected
to the determination of Tg. The obtained curve of variation of tan
.delta. is shown in FIG. 6. The highest peak (indicating Tg) is not
clear but the peak-forming area is observed in the temperature
range of 90 to 220.degree. C. This means that the cured protective
layer is rigid and hence has no enough flexibility to closely
contact with an encapsulant when the encapsulant was heated to
160.degree. C. for curing for final packaging.
[0188] [Evaluation of Cured Resin Composition on Affinity and
Fixation to Cured Encapsulant]
[0189] Each of the curable resin compositions prepared in Examples
1 to 15 and Comparison Examples 1 to 3 was coated on a luster
surface of an electrolytic copper foil (thickness: 35 .mu.m) to
give an insulating protective film of 30 .mu.m thick, and heated to
give a cured film. On the cured film was dropped a commercially
available encapsulant CEL-C-5020 (available from Hitachi Chemical
Industry Co., Ltd.) to give a liquid disc film (diameter: approx.
0.5 cm, thickness: approx. 1 mm). The liquid disc film was cured by
heating to 160.degree. C. for one hour. Thus obtained specimen was
manually bent to observe whether the cured disc film separated from
the insulating protective film or not.
[0190] The specimens prepared using the curable resin compositions
of Examples 1, 2, 5-8, and 10-15, and Comparison Example 2 showed
no separation between the cured disc film and the insulating
protective film. The specimens prepared using the curable resin
compositions of Examples 3, 4, and 9 showed partly separation
between the cured disc film and the insulating protective film. The
specimens prepared using the curable resin compositions of
Comparison Examples 1 and 3 showed apparent separation between the
cured disc film and the insulating protective film.
* * * * *