U.S. patent application number 15/470683 was filed with the patent office on 2017-07-13 for interlayer for laminated glass and laminated glass.
The applicant listed for this patent is SEKISUI CHEMICAL CO., LTD.. Invention is credited to Tatsuya Iwamoto, Kohei Kani, Shota Matsuda, Michio Shimamoto, Sinyul Yang.
Application Number | 20170197387 15/470683 |
Document ID | / |
Family ID | 45893255 |
Filed Date | 2017-07-13 |
United States Patent
Application |
20170197387 |
Kind Code |
A1 |
Shimamoto; Michio ; et
al. |
July 13, 2017 |
INTERLAYER FOR LAMINATED GLASS AND LAMINATED GLASS
Abstract
The present invention aims to provide an intermediate film for
laminated glass which, in the case of being used for constituting a
laminated glass, enables to improve the sound-insulating property
of a laminated glass to be obtained; and a laminated glass. The
intermediate film 1 for laminated glass of the present invention
comprises a first layer 2 which contains a polyvinyl acetal resin
and a plasticizer and the degree of acetylation of the polyvinyl
acetal resin contained in the first layer 2 exceeds 30 mol %; and
The laminated glass of the present invention comprises first and
second components for laminated glass, and the intermediate film 1
for laminated glass sandwiched between the first and second
components for laminated glass.
Inventors: |
Shimamoto; Michio; (Osaka,
JP) ; Matsuda; Shota; (Osaka, JP) ; Yang;
Sinyul; (Osaka, JP) ; Kani; Kohei;
(Kouka-city, JP) ; Iwamoto; Tatsuya; (Kouka-city,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SEKISUI CHEMICAL CO., LTD. |
Osaka |
|
JP |
|
|
Family ID: |
45893255 |
Appl. No.: |
15/470683 |
Filed: |
March 27, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13876062 |
Mar 26, 2013 |
9649828 |
|
|
PCT/JP2011/072615 |
Sep 30, 2011 |
|
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15470683 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B32B 2605/10 20130101;
B32B 7/02 20130101; B32B 17/10036 20130101; C08K 5/0016 20130101;
Y10T 428/31909 20150401; B32B 27/22 20130101; B32B 2250/03
20130101; B32B 27/08 20130101; B32B 27/30 20130101; B32B 2307/102
20130101; B32B 2605/18 20130101; B32B 2605/12 20130101; B32B
2605/08 20130101; Y10T 428/24942 20150115; C08L 29/14 20130101;
Y10T 428/3163 20150401; B32B 17/10761 20130101; C08K 5/0016
20130101 |
International
Class: |
B32B 17/10 20060101
B32B017/10; C08K 5/00 20060101 C08K005/00; B32B 7/02 20060101
B32B007/02; B32B 27/22 20060101 B32B027/22; B32B 27/30 20060101
B32B027/30 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 30, 2010 |
JP |
2010-222873 |
Jan 20, 2011 |
JP |
2011-009787 |
Jun 29, 2011 |
JP |
2011-144861 |
Claims
1. An intermediate film for laminated glass with a single layer
structure or a laminated structure of two or more layers,
comprising: a first layer containing a polyvinyl acetal resin and a
plasticizer, wherein a degree of acetylation of the polyvinyl
acetal resin contained in the first layer exceeds 30 mol %.
2. The intermediate film for laminated glass with a laminated
structure of two or more layers according to claim 1, further
comprising a second layer disposed at the side of a first surface
of the first layer.
3. The intermediate film for laminated glass according to claim 2,
wherein the second layer contains a polyvinyl acetal resin, and a
degree of acetylation of the polyvinyl acetal resin contained in
the second layer is lower than the degree of acetylation of the
polyvinyl acetal resin contained in the first layer.
4. The intermediate film for laminated glass according to claim 3,
wherein the degree of acetylation of the polyvinyl acetal resin
contained in the second layer is 30 mol % or lower.
5. The intermediate film for laminated glass according to claim 2,
wherein the second layer contains the polyvinyl acetal resin and a
plasticizer, and an amount of the plasticizer for each 100 parts by
weight of the polyvinyl acetal resin in the second layer is less
than an amount of the plasticizer for each 100 parts by weight of
the polyvinyl acetal resin in the first layer.
6. The intermediate film for laminated glass according to claim 2,
wherein the second layer is laminated on the first source of the
first layer.
7. The intermediate film for laminated glass with a laminated
structure of two or more layers according to claim 1, further
comprising a second layer which is laminated on a first surface of
the first layer and which contains a polyvinyl acetal resin and a
plasticizer, wherein an amount of the plasticizer is 50 parts by
weight or more for each 100 parts by weight of the polyvinyl acetal
resin in the first layer, a hydroxy group content in the polyvinyl
acetal resin contained in the first layer is lower than a hydroxy
group content in the polyvinyl acetal resin contained in the second
layer, the difference between the hydroxy group content in the
polyvinyl acetal resin contained in the first layer and the hydroxy
group content in the polyvinyl acetal resin contained in the second
layer is 9.2 mol % or smaller.
8. The intermediate film for laminated glass according to claim 1,
wherein the polyvinyl acetal resin contained in the first layer
contain a high-molecular-weight component with an absolute
molecular weight of 1,000,000 or higher and a proportion of the
high-molecular-weight component in the polyvinyl acetal resin
contained in the first layer is 7.4% or higher, or the polyvinyl
acetal resin contained in the first layer contains a
high-molecular-weight component with a molecular weight in terms of
polystyrene of 1,000,000 or higher and a proportion of the high
molecular-weight component in the polyvinyl acetal resin contained
in the first layer is 9% or higher.
9. The intermediate film for laminated glass according to claim 1,
wherein a ratio (G'(Tg+80)/G'(Tg+30)) of an elastic modulus
G'(Tg+80) at (Tg+80).degree. C. to an elastic modulus G'(Tg+30) at
(Tg+30) .degree. C. is 0.65 or higher, provided that the first
layer is used as a resin film and a viscoelasticity of the resin
film is measured, and that Tg(.degree. C.) represents a glass
transition temperature of the resin film.
10. The intermediate film for laminated glass according to claim 1,
wherein a ratio (G'(Tg+80)/G'(Tg+30)) of an elastic modulus
G'(Tg+80) at (Tg+80).degree. C. to an elastic modulus G'(Tg+30) at
(Tg+30).degree. C. is 0.65 or higher, provided that a resin film
containing 100 parts by weight of the polyvinyl acetal resin
contained in the first layer and 60 parts by weight of triethylene
glycol di-2-ethyl hexanoate (3GO) as a plasticizer is prepared and
a viscoelasticity of the resin film is measured, and that
Tg(.degree. C.) represents a glass transition temperature of the
resin film.
11. The intermediate film for laminated glass according to claim 1,
wherein the polyvinyl acetal resin contained in the first layer is
obtained by acetalizing a polyvinyl alcohol resin having an average
degree of polymerization exceeding 3,000.
12. The intermediate film for laminated glass with a laminated
structure of three or more layers according to claim 1, further
comprising: a second layer disposed at the side of a first surface
of the first layer; and a third layer disposed at the side of a
second surface that is opposite to the first surface of the first
layer.
13. The intermediate film for laminated glass according to claim
12, wherein the third layer contains a polyvinyl acetal resin, and
a degree of acetylation of the polyvinyl acetal resin contained in
the third layer is lower than a degree of acetylation of the
polyvinyl acetal resin contained in the first layer.
14. The intermediate film for laminated glass according to claim
13, wherein the degree of acetylation of the polyvinyl acetal resin
contained in the third layer is 30 mol % or lower.
15. The intermediate film for laminated glass according to claim
12, wherein the third layer contains a polyvinyl acetal resin and a
plasticizer, and an amount of the plasticizer for each 100 parts by
weight of the polyvinyl acetal resin in the third layer is lower
than an amount of the plasticizer for each 100 parts by weight of
the polyvinyl acetal resin in the first layer.
16. The intermediate film for laminated glass according to claim
12, wherein the third layer is laminated on the second surface of
the first layer.
17. A laminated glass, comprising a first component for laminated
glass; a second component for laminated glass; and an intermediate
film sandwiched between the first component for laminated glass and
the second component for laminated glass, wherein the intermediate
film is the intermediate film for laminated glass according to
claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation application of patent
application Ser. No. 13/876,062, filed on Mar. 26, 2013, which is a
371 application of application Ser. No. PCT/JP2011/072615, filed on
Sep. 30, 2011, which is based on Japanese Patent Application Nos.
2010-222873, 2011-009787 and 2011-144861 filed on Sep. 30, 2010,
Jan. 20, 2011 and Jun. 29, 2011, respectively, the entire contents
of which are hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to an intermediate film for
laminated glass used for laminated glasses of automobiles and
buildings. The present invention specifically relates to an
intermediate film for laminated glass containing a polyvinyl acetal
resin and a plasticizer, and a laminated glass comprising the
intermediate film for laminated glass.
BACKGROUND ART
[0003] Laminated glasses scatter fewer pieces of broken glass when
they are damaged by external impact, and thus are excellently safe.
Therefore, such laminated glasses are widely used in automobiles,
railway carriages, aircrafts, ships, buildings, and the like. The
laminated glass is produced by interposing an intermediate film
between a pair of glass plates.
[0004] In order to reduce the weight of a laminated glass, studies
have recently been performed for making a laminated glass thin. A
thinner laminated glass, however, has a reduced sound-insulating
property. It a laminated glass with a reduced sound-insulating
property is used for the windshield of an automobile, its
sound-insulating property is disadvantageously insufficient against
sounds at a register of about 5,000 Hz, such as wind noise and
driving sound of wipers.
[0005] Then, additional studies have been performed for increasing
the sound-insulating property of a laminated glass by changing
materials of an intermediate film.
[0006] Patent Document 1 discloses, as one example of an
intermediate film for laminated glass, a sound-insulating layer
comprising 100 parts by weight of a polyvinyl acetal resin with a
degree of acetalization of 60 to 85 mol %, 0.001 to 1.0 parts by
weight of at least one metal salt selected from alkali metal salts
and alkaline earth metal salts, and 30 parts by weight or more of a
plasticizer. This sound-insulating layer can be used alone as an
intermediate film, or can be laminated with another layer and used
as a multilayer intermediate film.
PRIOR ART DOCUMENT
Patent Document
[0007] Patent Document 1: JP 2007-070200 A
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
[0008] The intermediate film for laminated glass disclosed in the
above Patent Document 1 can improve the sound-insulating property
of a laminated glass to some extent, but a further improved
sound-insulating property is required.
[0009] In the case of forming a laminated glass using the
intermediate film disclosed in Patent Document 1, for example, the
sound-insulating property of the laminated glass in a relatively
high frequency range is insufficient, and thus reduction in the
sound-insulating property due to the coincidence effect cannot be
avoided in some cases. In particular, the sound-insulating property
of this laminated glass may be insufficient at around 20.degree.
C.
[0010] Here, the coincidence effect is a phenomenon that, when
sound waves strike a glass plate, the transverse wave is propagated
on the glass surface due to the rigidity and inertia of the glass
plate, and then the transverse wave resonates with the incident
sound, so that the sound is transmitted.
[0011] Further, in the case of forming a laminated glass using a
multilayer intermediate film disclosed in Patent Document 1 in
which the sound-insulating layer and other layers are laminated,
the sound-insulating property of the laminated glass at around
20.degree. C. can be improved to some extent. In this case,
however, the multilayer intermediate film has the sound-insulating
layer, and thus bubble formation may occur in the laminated glass
including the multilayer intermediate film.
[0012] Furthermore, recently, it has been studied to increase the
amount of a plasticizer contained in an intermediate film in order
to improve the sound-insulating property of a laminated glass. As
the amount of a plasticizer in an intermediate film increases, the
sound-insulating property of the laminated glass can be improved.
If the amount of a plasticizer increases, however, bubble formation
may occur in the laminated glass.
[0013] An object of the present invention is to provide an
intermediate film for laminated glass which, if it is used for
forming a laminated glass, can improve the sound-insulating
property of the laminated glass to be obtained; and a laminated
glass comprising the intermediate film for laminated glass.
[0014] A limitative object of the present invention is to provide
an intermediate film for laminated glass which can provide a
laminated glass that not only has a high sound-insulating property
but also suppresses bubble formation and bubble growth; and a
laminated glass comprising the intermediate film for laminated
glass.
Means for Solving the Problems
[0015] According to one wide aspect of the present invention, an
intermediate film for laminated glass with a single layer structure
or a laminated structure of two or more layers is provided, the
intermediate film comprising: a first layer containing a polyvinyl
acetal resin and a plasticizer, wherein a degree of acetylation of
the polyvinyl acetal resin contained in the first layer exceeds 30
mol %. The intermediate film for laminated glass of the present
invention may be a single layer intermediate film for laminated
glass only comprising the first layer, or may be a multilayer
intermediate film for laminated glass comprising the first
layer.
[0016] In a certain specific aspect of the intermediate film for
laminated glass of the present invention, the intermediate film for
laminated glass has a laminated structure of two or more layers,
further comprising a second layer disposed at the side of a first
surface of the first layer.
[0017] In another specific aspect of the intermediate film for
laminated glass of the present invention, the second layer contains
a polyvinyl acetal resin, and a degree of acetylation of the
polyvinyl acetal resin contained in the second layer is lower than
the degree of acetylation of the polyvinyl acetal resin contained
in the first layer.
[0018] In still another specific aspect of the intermediate film
for laminated glass of the present invention, the degree of
acetylation of the polyvinyl acetal resin contained in the second
layer is 30 mol % or lower.
[0019] In another specific aspect of the intermediate film for
laminated glass of the present invention, the second layer contains
the polyvinyl acetal resin and a plasticizer, and an amount of the
plasticizer for each 100 parts by weight of the polyvinyl acetal
resin in the second layer is less than an amount of the plasticizer
for each 100 parts by weight of the polyvinyl acetal resin in the
first layer.
[0020] In still another specific aspect of the intermediate film
for laminated glass of the present invention, the second layer is
laminated on the first surface of the first layer.
[0021] In another specific aspect of the intermediate film for
laminated glass of the present invention, the intermediate film for
laminated glass has a laminated structure of two or more layers,
the intermediate film further comprising a second layer which is
laminated on a first surface of the first layer and which contains
a polyvinyl acetal resin and a plasticizer, wherein an amount of
the plasticizer is 50 parts by weight or more for each 100 parts by
weight of the polyvinyl acetal resin in the first layer, a hydroxy
group content in the polyvinyl acetal resin contained in the first
layer is lower than a hydroxy group content in the polyvinyl acetal
resin contained in the second layer, the difference between the
hydroxy group content in the polyvinyl acetal resin contained in
the first layer and the hydroxy group content in the polyvinyl
acetal resin contained in the second layer is 9.2 mol % or smaller,
and the degree of acetylation of the polyvinyl acetal resin
contained in the first layer is 8 mol % or lower if the difference
between the hydroxy group content in the polyvinyl acetal resin
contained in the first layer and the hydroxy group content in the
polyvinyl acetal resin contained in the second layer is greater
than 8.5 mol % but not greater than 9.2 mol %.
[0022] In still another specific aspect of the intermediate film
for laminated glass of the present invention, the polyvinyl acetal
resin contained in the first layer contains a high-molecular-weight
component with an absolute molecular weight of 1,000,000 or higher
and a proportion of the high-molecular-weight component in the
polyvinyl acetal resin contained in the first layer is 7.4% or
higher, or the polyvinyl acetal resin contained in the first layer
contains a high-molecular-weight component with a molecular weight
in terms of polystyrene of 1,000,000 or higher and a proportion of
the high-molecular-weight component in the polyvinyl acetal resin
contained in the first layer is 9% or higher.
[0023] In another specific aspect of the intermediate film for
laminated glass of the present invention, a ratio
(G'(Tg+80)/G'(Tg+30)) of an elastic modulus G'(Tg+80) at
(Tg+80).degree. C. to an elastic modulus G'(Tg+30) at
(Tg+30).degree. C. is 0.65 or higher, provided that the first layer
is used as a resin film and a viscoelasticity of the resin film is
measured, and that Tg(.degree. C.) represents a glass transition
temperature of the resin film.
[0024] In still another specific aspect of the intermediate film
for laminated glass of the present invention, a ratio
(G'(Tg+80)/G'(Tg+30)) of an elastic modulus G'(Tg+80) at
(Tg+80).degree. C. to an elastic modulus G'(Tg+30) at
(Tg+30.degree.).degree. C. is 0.65 or higher, provided that a resin
film containing 100 parts by weight of the polyvinyl acetal resin
contained in the first layer and 60 parts by weight of triethylene
glycol di-2-ethyl hexanoate (3GO) as a plasticizer is prepared and
a viscoelasticity of the resin film is measured, and that
Tg(.degree. C.) represents a glass transition temperature of the
resin film.
[0025] In another specific aspect of the intermediate film for
laminated glass of the present invention, the polyvinyl acetal
resin contained in the first layer is obtained by acetalizing a
polyvinyl alcohol resin having an average degree of polymerization
exceeding 3,000.
[0026] In another specific aspect of the intermediate film for
laminated glass of the present invention, the intermediate film for
laminated glass has a laminated structure of three or more layers,
the intermediate film further comprising: a second layer disposed
at the side of a first surface of the first layer; and a third
layer disposed at the side of a second surface that is opposite to
the first surface of the first layer.
[0027] In another specific aspect of the intermediate film for
laminated glass of the present invention, the third layer contains
a polyvinyl acetal resin, and a degree of acetylation of the
polyvinyl acetal resin contained in the third layer is lower than a
degree of acetylation of the polyvinyl acetal resin contained in
the first layer.
[0028] In still another specific aspect of the intermediate film
for laminated glass of the present invention, the degree of
acetylation of the polyvinyl acetal resin contained in the third
layer is 30 mol % or lower.
[0029] In another specific aspect of the intermediate film for
laminated glass of the present invention, the third layer contains
a polyvinyl acetal resin and a plasticizer, and an amount of the
plasticizer for each 100 parts by weight of the polyvinyl acetal
resin in the third layer is lower than an amount of the plasticizer
for each 100 parts by weight of the polyvinyl acetal resin in the
first layer.
[0030] In still another specific aspect of the intermediate film
for laminated glass of the present invention, the third layer is
laminated on the second surface of the first layer.
[0031] The laminated glass of the present invention comprises a
first component for laminated glass; a second component for
laminated glass; and an intermediate film sandwiched between the
first component for laminated glass and the second component for
laminated glass, wherein the intermediate film is the intermediate
film for laminated glass formed according to the present
invention.
Effect of the Invention
[0032] The intermediate film for laminated glass of the present
invention comprises a first layer which contains a polyvinyl acetal
resin and a plasticizer, and the degree of acetylation of the
polyvinyl acetal resin contained in the first layer exceeds 30 mol
%. Thus, the sound-insulating property of a laminated glass
comprising the intermediate film for laminated glass of the present
invention can be improved.
BRIEF DESCRIPTION OF DRAWINGS
[0033] FIG. 1 is a partially cut cross-sectional view schematically
showing an intermediate film for laminated glass according to one
embodiment of the present invention.
[0034] FIG. 2 is a partially cut cross-sectional view schematically
showing one example of a laminated glass using the intermediate
film for laminated glass shown in FIG. 1.
[0035] FIG. 3 is a diagram for illustrating the relationship
between the loss factor tan .delta. and the temperature and the
relationship between the elastic modulus G' and the temperature in
the case that a resin film containing a polyvinyl acetal resin and
triethylene glycol di-2-ethyl hexanoate contained in the first
layer is prepared and the viscoelasticity of the resin film is
measured.
MODE(S) FOR CARRYING OUT THE INVENTION
[0036] The following will describe specific embodiments and
examples of the present invention referring to the drawings, and
thereby clarify the present invention.
[0037] FIG. 1 is a partially cut cross-sectional view schematically
showing an intermediate film for laminated glass according to one
embodiment of the present invention.
[0038] An intermediate film 1 shown in FIG. 1 is a multilayer
intermediate film. The intermediate film 1 is used for obtaining a
laminated glass. The intermediate film 1 is an intermediate film
for laminated glass. The intermediate film 1 comprises a first
layer 2, a second layer 3 disposed on the side of a first surface
2a of the first layer 2, and a third layer 4 disposed on the side
of a second surface 2b opposite to the first surface 2a of the
first layer 2. The second layer 3 is laminated on the first surface
2a of the first layer 2. The third layer 4 is laminated on the
second surface 2b of the first layer 2. The first layer 2 is an
intermediate layer, and mainly functions as a sound-insulating
layer. The second layer 3 and the third layer 4 are protecting
layers, and are surface layers in the present embodiment. The first
layer 2 is disposed between the second layer 3 and the third layer
4. The first layer 2 is sandwiched between the second layer 3 and
the third layer 4. Thus, the intermediate film 1 has a multilayer
structure in which the second layer 3, the first layer 2, and the
third layer 4 are laminated in this order.
[0039] In addition, other layers may be laminated between the first
layer 2 and the second layer 3 and between the first layer 2 and
the third layer 4. Preferably, the first layer 2 and the second
layer 3, and the first layer 2 and the third layer 4 each are
laminated directly. Examples of other layers include layers
containing a thermoplastic resin such as polyvinyl acetal resin,
and layers containing polyethylene terephthalate.
[0040] The first layer 2 contains a polyvinyl acetal resin with a
degree of acetylation exceeding 30 mol % and a plasticizer. The
second layer 3 preferably contains a polyvinyl acetal resin, and
preferably contains a polyvinyl acetal resin and a plasticizer. The
second layer 3 contains, for example, a polyvinyl acetal resin with
a degree of acetylation of 30 mol % or lower and a plasticizer. The
third layer 4 preferably contains a polyvinyl acetal resin, and
preferably contains a polyvinyl acetal resin and a plasticizer. The
third layer 4 contains, for example, a polyvinyl acetal resin with
a degree of acetylation of 30 mol % or lower and a plasticizer. The
composition of the first layer 2 and the compositions of the second
layer 3 and the third layer 4 are preferably different from each
other. The compositions of the second layer 3 and the third layer 4
may be the same as or different from each other.
[0041] The main features of the present embodiment are that the
first layer 2 containing a polyvinyl acetal resin and a plasticizer
is comprised and a degree of acetylation of the polyvinyl acetal
resin contained in the first layer 2 has a degree of acetylation
exceeds 30 mol %. In particular, the present embodiment has an
important feature in that the degree of acetylation of the
polyvinyl acetal resin contained in the first layer 2 is as high as
exceeding 30 mol %. Thereby, the sound-insulating property of a
laminated glass comprising the intermediate film 1 can be
improved.
[0042] Especially, the first layer 2 containing a polyvinyl acetal
resin with a degree of acetylation exceeding 30 mol % can improve
the sound-insulating property within a temperature range of
20.degree. C. to 30.degree. C.
[0043] In recent years, fuel automobiles using internal-combustion
engines are being switched over to electric vehicles using electric
motors, and hybrid electric vehicles using internal-combustion
engines and electric motors, and the like. Laminated glasses used
for fuel automobiles using internal-combustion engines are
particularly required to have a sound-insulating property against
sounds in a relatively low frequency range. Even laminated glasses
used for fuel automobiles using internal-combustion engines also
preferably have a high sound-insulating property against sounds in
a high frequency range. In contrast, laminated glasses used for
electric vehicles and hybrid electric vehicles utilizing electric
motors are particularly required to have a high sound-insulating
property against sounds in a high frequency range in order to
effectively insulate driving sounds of their electric motors.
[0044] The present inventors have also found that the first layer 2
containing a polyvinyl acetal resin with a degree of acetylation
exceeding 30 mol % can effectively and sufficiently improve the
sound-insulating property in a high frequency range of a laminated
glass.
[0045] In the intermediate film 1, the second layer 3 and the third
layer 4 are laminated on the respective faces of the first layer 2.
The second layer is preferably disposed on the side of a first
surface of the first layer, and the second layer is preferably
laminated on the first surface of the first layer. The second layer
may be disposed only on the side of the first surface of the first
layer, and the third layer may not be disposed on the side of a
second surface of the first layer. Nevertheless, it is preferable
that the second layer is disposed on the side of the first surface
of the first layer and the third layer is disposed on the second
surface of the first layer. The third layer is preferably laminated
on the second surface of the first layer. As the third layer is
laminated on the second surface of the first layer, the penetration
resistance of a laminated glass comprising the intermediate film 1
can be further improved.
[0046] With an intermediate film for laminated glass having a
multilayer structure that provides an improved sound-insulating
property, bubble formation problematically easily occurs in the
laminated glass. With respect to such a problem, the present
inventors have found that, in an intermediate film for laminated
glass with a multilayer structure, plasticizers transfer between
the respective layers and, as a result, a layer containing a larger
amount of plasticizer is formed, that is, for example, the
plasticizers transfer from the second layer and the third layer to
the first layer so that the amount of the plasticizer in the first
layer increases. The present inventors have further found that, as
the layer containing a larger amount of plasticizer is formed, in
other words, as the amount of the plasticizer in the first layer
increases, bubble formation is likely to occur in a laminated glass
comprising the intermediate film for laminated glass, and bubble
formation once occurs, the generated bubbles tend to serve as cores
and thereby to cause bubble growth.
[0047] From the viewpoint of suppressing bubble formation and
bubble growth in a laminated glass, preferably, the amount of the
plasticizer is 50 parts by weight or more for each 100 parts by
weight of the polyvinyl acetal resin in the first layer 2; the
hydroxy group content in the polyvinyl acetal resin contained in
the first layer 2 is lower than the hydroxy group content in the
polyvinyl acetal resin contained in the second layer 3; the
difference between the hydroxy group content in the polyvinyl
acetal resin contained in the first layer 2 and the hydroxy group
content in the polyvinyl acetal resin contained in the second layer
3 (hereinafter, also referred to as a content difference (1-2)) is
9.2 mol % or smaller; and if the difference between the hydroxy
group content in the polyvinyl acetal resin contained in the first
layer 2 and the hydroxy group content in the polyvinyl acetal resin
contained in the second layer 3 (content difference (1-2)) is
greater than 8.5 mol % but not greater than 9.2 mol %, the degree
of acetylation of the polyvinyl acetal resin contained in the first
layer 2 is preferably 8 mol % or lower. The content difference
(1-2) may be greater than 8.5 mol % but not greater than 9.2 mol %,
and further may be 8.5 mol % or smaller.
[0048] Preferably, the hydroxy group content in the polyvinyl
acetal resin contained in the first layer 2 is lower than the
hydroxy group content in the polyvinyl acetal resin contained in
the third layer 4; the difference between the hydroxy group content
in the polyvinyl acetal resin contained in the first layer 2 and
the hydroxy group content in the polyvinyl acetal resin contained
in the third layer 4 (hereinafter, also referred to as a content
difference (1-3)) is 9.2 mol % or smaller; and if the difference
between the hydroxy group content in the polyvinyl acetal resin
contained in the first layer 2 and the hydroxy group content in the
polyvinyl acetal resin contained in the third layer 4 (content
difference (1-3)) is greater than 8.5 mol % but not greater than
9.2 mol %, the degree of acetylation of the polyvinyl acetal resin
contained in the first layer 2 is 8 mol % or lower. Even in the
case that the content difference (1-3) is 8.5 mol % or smaller,
however, the degree of acetylation of the polyvinyl acetal resin
contained in the first layer 2 is preferably 8 mol % or lower if
the content difference (1-2) is greater than 8.5 mol % but not
greater than 9.2 mol %. The content difference (1-3) may be greater
than 8.5 mol % but not greater than 9.2 mol % or lower, and further
may be 8.5 mol % or smaller.
[0049] The present inventors have performed studies for suppressing
bubble formation and bubble growth, and thereby found that the
aforementioned control of the hydroxy group contents in the
polyvinyl acetal resins contained in the first layer, the second
layer and the third layer enables to sufficiently suppress bubble
formation and bubble growth in a laminated glass. Since transition
of the plasticizer can be suppressed and bubble formation and
bubble growth in a laminated glass can be sufficiently suppressed,
the amount of the plasticizer in each layer, especially the amount
of the plasticizer in the first layer 2, can be increased. As a
result, the sound-insulating property of the laminated glass can be
furthermore improved.
[0050] If the amount of the plasticizer for each 100 parts by
weight of the polyvinyl acetal resin in the first layer 2 is more
than the amount of the plasticizer for each 100 parts by weight of
the polyvinyl acetal resin in each of the second layer 3 and the
third layer 4, bubble formation tends to more easily occur. In
addition, bubble formation once occurs, the generated bubbles tend
to serve as cores and thereby to cause bubble growth. In contrast,
if the hydroxy group contents in the polyvinyl acetal resins
contained in the first layer, the second layer and the third layer
are controlled as mentioned above, bubble formation and bubble
growth in a laminated glass can be sufficiently suppressed.
[0051] From the viewpoint of further suppressing bubble formation
and bubble growth in a laminated glass, with respect to the
difference between the hydroxy group content in the polyvinyl
acetal resin contained in the first layer 2 and each of the hydroxy
group contents in the polyvinyl acetal resins contained in the
second layer 3 and the third layer 4 (content difference (1-2) and
content difference (1-3)), the lower limit thereof is preferably
0.1 mol %, more preferably 1 mol %, and still more preferably 2 mol
%, whereas the upper limit thereof is preferably 8.5 mol %, more
preferably 7.8 mol %, still more preferably 7 mol %, and
particularly preferably 5.6 mol %. Because bubble formation and
bubble growth can be furthermore suppressed in a laminated glass,
the difference between the hydroxy group content in the polyvinyl
acetal resin contained in the first layer 2 and each of the hydroxy
group contents in the polyvinyl acetal resins contained in the
second layer 3 and the third layer 4 (content difference (1-2) and
content difference (1-3)) is preferably 5 mol % or smaller, more
preferably 4.5 mol % or smaller, still more preferably 4 mol % or
smaller, and furthermore preferably 3.5 mol % or smaller.
[0052] Preferably, the polyvinyl acetal resin contained in the
first layer 2 contains a high-molecular-weight component with an
absolute molecular weight of 1,000,000 or higher (hereinafter, also
referred to as a high-molecular-weight component X), or the
polyvinyl acetal resin contained in the first layer 2 contains a
high-molecular-weight component with a polystyrene-equivalent
molecular weight (hereinafter, also referred to as a molecular
weight y) of 1,000,000 or higher (hereinafter, also referred to as
a high-molecular-weight component Y). The high-molecular-weight
component X and the high-molecular-weight component Y are polyvinyl
acetal resins. The proportion of the high-molecular-weight
component X in the polyvinyl acetal resin contained in the first
layer 2 is preferably 7.4% or higher, or the proportion of the
high-molecular-weight component Y in the polyvinyl acetal resin
contained in the first layer 2 is preferably 9% or higher.
[0053] As the polyvinyl acetal resin contained in the first layer 2
contains the high-molecular-weight component X with an absolute
molecular weight of 1,000,000 or higher at the aforementioned
specific proportion, bubble formation in a laminated glass can be
suppressed. As the polyvinyl acetal resin contained in the first
layer 2 contains the high-molecular-weight component Y with a
molecular weight y of 1,000,000 or higher at the aforementioned
specific proportion, bubble formation in a laminated glass can also
be suppressed.
[0054] The proportion of the high-molecular-weight component X in
the polyvinyl acetal resin contained in the first layer 2 is
defined as a value in terms of percentage (%) of the ratio of the
area of a region corresponding to the high-molecular-weight
component X in the peak area of the polyvinyl acetal resin
component obtained upon measuring the absolute molecular weight.
Also, the proportion of the high-molecular-weight component Y in
the polyvinyl acetal resin contained in the first layer 2 is
defined as a value in terms of percentage (%) of the ratio of the
area of a region corresponding to the high-molecular-weight
component Y in the peak area of the polyvinyl acetal resin
component obtained upon measuring the molecular weight in terms of
polystyrene.
[0055] The compositions of the second layer 3 and the third layer 4
each are preferably different from the composition of the first
layer 2. The polyvinyl acetal resin in each of the second layer 3
and the third layer 4 may contain a high-molecular-weight component
X with an absolute molecular weight of 1,000,000 or higher and the
proportion of the high-molecular-weight component X in the
polyvinyl acetal resin contained in each of the second layer 3 and
the third layer 4 may be 7.4% or higher. It may also contain a
high-molecular-weight component Y with a molecular weight y of
1,000,000 or higher and the proportion of the high-molecular-weight
component Y in the polyvinyl acetal resin contained in each of the
second layer 3 and the third layer 4 may be 9% or higher.
[0056] From the viewpoints of further improving the
sound-insulating property of a laminated glass and further
suppressing bubble formation and bubble growth, with respect to the
proportion of the high-molecular-weight component X with an
absolute molecular weight of 1,000,000 or higher in the polyvinyl
acetal resin contained in the first layer 2, a preferable lower
limit is 8%, a more preferable lower limit is 8.5%, a still more
preferable lower limit is 9%, a particularly preferable lower limit
is 9.5%, and a most preferable lower limit is 10%. Because the
sound-insulating property of a laminated glass can be further
improved and bubble formation and bubble growth can be further
suppressed, the proportion of the high-molecular-weight component X
is preferably 11% or higher, more preferably 12% or higher, still
more preferably 14% or higher, and particularly preferably 16% or
higher. The upper limit of the proportion of the
high-molecular-weight component X is not particularly limited, and
a preferable upper limit is 40%, a more preferable upper limit is
30%, and a still more preferable upper limit is 25%.
[0057] In the case that the polyvinyl acetal resin contained in the
first layer 2 contains the high-molecular-weight component Y with a
molecular weight y of 1,000,000 or higher, with respect to the
proportion of the high-molecular-weight component Y with a
molecular weight y of 1,000,000 or higher in the polyvinyl acetal
resin contained in the first layer 2 containing the
high-molecular-weight component Y, a preferable lower limit is 10%,
a more preferable lower limit is 11%, a still more preferable lower
limit is 11.5%, and a particularly preferable lower limit is 12%.
Because the sound-insulating property of a laminated glass can be
further improved and bubble formation and bubble growth can be
further improved, the proportion of the high-molecular-weight
component Y is preferably 12.5% or higher, more preferably 13.5% or
higher, still more preferably 14% or higher, particularly
preferably 15% or higher, and most preferably 18% or higher. The
upper limit of the proportion of the high-molecular-weight
component Y is not particularly limited, and a preferable upper
limit is 40%, a more preferable upper limit is 30%, and a still
more preferable upper limit is 25%. If the proportion of the
high-molecular-weight component Y is not lower than the lower
limit, the sound-insulating property of a laminated glass can be
further improved and bubble formation and bubble growth can be
further suppressed.
[0058] In the case that a resin film A containing 100 parts by
weight of the polyvinyl acetal resin contained in the first layer 2
and 60 parts by weight of triethylene glycol di-2-ethyl hexanoate
(3GO) as a plasticizer is used and the viscoelasticity of the resin
film A is measured (test method A), the ratio (G'(Tg+80)/G'(Tg+30))
of the elastic modulus G'(Tg+80) at (Tg+80) .degree. C. to the
elastic modulus G'(Tg+30) at (Tg+30).degree. C. is preferably 0.65
or higher, provided that Tg(.degree. C.) represents a glass
transition temperature of the resin film A.
[0059] Also, in the case that the first layer 2 is used as a resin
film B and the viscoelasticity of the resin film B is measured
(test method B), the ratio (G'(Tg+80)/G'(Tg+30)) of the elastic
modulus G'(Tg+80) at (Tg+80) .degree. C. to the elastic modulus
G'(Tg+30) at (Tg+30.degree.).degree. C. is preferably 0.65 or
higher, provided that Tg(.degree. C.) represents the glass
transition temperature of the resin film B.
[0060] In the test method B, the first layer 2 is used as the resin
film B, and the first layer 2 itself is the resin film B.
[0061] The resin film B is the first layer 2, and it contains the
polyvinyl acetal resin and the plasticizer at the weight ratio as
in the first layer 2. In the test method B, preferably, the
plasticizer is transferred in the intermediate film 1 for laminated
glass, and then the elastic modulus G'(Tg+80) and the elastic
modulus G'(Tg+30) are measured. In the test method B, more
preferably, the intermediate film 1 for laminated glass is stored
at a humidity of 30% (.+-.3%) and at a temperature of 23.degree. C.
for one month so that the plasticizer is transferred in the
intermediate film 1 for laminated glass, and then the elastic
modulus G'(Tg+80) and the elastic modulus G'(Tg+30) are
measured.
[0062] The present inventors have performed studies for suppressing
bubble formation and bubble growth, and thereby also found that a
ratio (G'(Tg+80)/G'(Tg+30)) of 0.65 or higher in the test method A
or the test method B enables to sufficiently suppress bubble
formation and bubble growth in a laminated glass. Even in the case
that the amount of the plasticizer in the first layer 2 is large,
bubble formation and bubble growth in a laminated glass can be
sufficiently suppressed. Thus, the sound-insulating property of the
laminated glass can be improved. In particular, use of an
intermediate film 1 for laminated glass in which the second layer 3
and the third layer 4 are laminated on the respective surfaces of
the first layer 2 configured to have a ratio (G'(Tg+80)/G'(Tg+30))
of 0.65 or higher leads to further suppression of bubble formation
and bubble growth in a laminated glass.
[0063] The ratio (G'(Tg+80)/G'(Tg+30)) is 0.65 or higher, and
preferably 1.0 or lower. A ratio (G'(Tg+80)/G'(Tg+30)) of 0.65 or
higher may enable to sufficiently suppress bubble formation and
bubble growth in a laminated glass even after the laminated glass
is stored under considerably severe conditions or for a long term.
Further, a ratio (G'(Tg+80)/G'(Tg+30)) not lower than the lower
limit and not higher than the upper limit may enable to more
effectively suppress bubble formation and bubble growth in a
laminated glass even after the laminated glass is stored under
considerably severe conditions or for a long term.
[0064] From the viewpoint of sufficiently improving the
sound-insulating property of a laminated glass, the amount of the
plasticizer is preferably 40 parts by weight or more for each 100
parts by weight of the polyvinyl acetal resin in the first layer 2.
Even in the case that the amount of the plasticizer in the first
layer is large, the first layer configured to have a ratio
(G'(Tg+80)/G'(Tg+30)) of 0.65 or higher may enable to suppress
bubble formation and bubble growth in a laminated glass.
[0065] The glass transition temperature Tg(.degree. C.) indicates a
peak temperature of the loss factor tan .delta. obtainable from the
measurement result of the viscoelasticity. From the viewpoint of
further suppressing bubble formation and bubble growth in a
laminated glass, the ratio (G'(Tg+80)/G'(Tg+30)) is more preferably
0.7 or higher, whereas more preferably 0.95 or lower, and still
more preferably 0.75 or higher, whereas still more preferably 0.9
or lower. Particularly, in the case of controlling the ratio
(G'(Tg+80)/G'(Tg+30)) by the average degree of polymerization of
polyvinyl alcohol resin, the ratio (G'(Tg+80)/G'(Tg+30)) is
preferably 0.65 or higher, more preferably 0.66 or higher, still
more preferably 0.67 or higher, and particularly preferably 0.7 or
higher, whereas preferably 0.82 or lower, and more preferably 0.8
or lower, because bubble formation and bubble growth in a laminated
glass can be sufficiently suppressed and the sound-insulating
property of the laminated glass can be further improved.
Furthermore, if the ratio (G'(Tg+80)/G'(Tg+30)) is 0.82 or lower,
or 0.8 or lower, an intermediate film can be easily formed.
[0066] Examples of the method for controlling the ratio
(G'(Tg+80)/G'(Tg+30)) measured by the test method A or the test
method B to 0.65 or higher include a method of using a polyvinyl
alcohol resin with a relatively high average degree of
polymerization upon synthesis of a polyvinyl acetal resin to be
contained in the first layer 2; and a method of strengthening the
inter-molecular interaction of the polyvinyl acetal resin contained
in the first layer 2. Examples of the method of strengthening the
inter-molecular interaction of the polyvinyl acetal resin contained
in the first layer 2 include a method of physically cross-linking
the molecules of the polyvinyl acetal resin, and a method of
chemically cross-linking the molecules. Particularly preferable are
a method of using a polyvinyl alcohol resin with a relatively high
average degree of polymerization upon synthesis of a polyvinyl
acetal resin to be contained in the first layer 2 and a method of
physically cross-linking the molecules of the polyvinyl acetal
resin contained in the first layer 2 because the intermediate film
1 can be easily formed using an extruder.
[0067] The following will describe one example of the relationship
between the loss factor tan .delta. and the temperature and the
relationship between the elastic modulus G' and the temperature
obtained by the aforementioned measurement of the viscoelasticity
referring to FIG. 3.
[0068] The loss factor tan .delta. and the temperature show the
relationship shown in FIG. 3. The temperature at the peak P of the
loss factor tan .delta. is the glass transition temperature Tg.
[0069] In FIG. 3, the glass transition temperature Tg in the
elastic modulus G' drawn with the broken line A2 and the glass
transition temperature Tg in the elastic modulus G' drawn with the
solid line A1 are the same temperature. For example, as the amount
of change D of the elastic modulus G'(Tg+80) based on the elastic
modulus G'(Tg+30) is smaller, bubble formation and bubble growth in
a laminated glass can be more effectively suppressed. The amount of
change D1 in the elastic modulus G' drawn with the solid line A1 is
smaller than the amount of change D2 in the elastic modulus G'
drawn with the broken line A2. Thus, in FIG. 3, bubble formation
and bubble growth in a laminated glass can be more effectively
suppressed in the case of the elastic modulus G' drawn with the
solid line A1 in which the amount of change D1 is relatively small
than in the case of the elastic modulus G' drawn with the broken
line A2 in which the amount of change D2 is relatively large.
[0070] The elastic modulus G'(Tg+30) is preferably 200,000 Pa or
higher. The elastic modulus G'(Tg+30) is more preferably 220,000 Pa
or higher, still more preferably 230,000 Pa or higher, and
particularly preferably 240,000 Pa or higher, whereas preferably
10,000,000 Pa or lower, more preferably 5,000,000 Pa or lower,
particularly preferably 1,000,000 Pa or lower, most preferably
500,000 Pa or lower, and still most preferably 300,000 Pa or lower.
An elastic modulus G'(Tg+30) not lower than the lower limit may
enable to further suppress bubble formation and bubble growth in a
laminated glass.
[0071] Here, the relationship between the elastic modulus G' and
the temperature is greatly influenced by the type of a polyvinyl
acetal resin and, in particular, it is greatly influenced by the
average degree of polymerization of the polyvinyl alcohol resin
used for providing a polyvinyl acetal resin. The relationship is
not greatly influenced by the type of a plasticizer and, if the
plasticizer is used in a usual amount of plasticizer, the amount of
the plasticizer does not have a great influence thereon. In the
case of using a plasticizer such as a monobasic organic acid ester
other than 3GO instead of 3GO, especially in the case of using a
diester plasticizer represented by the following formula (1) other
than 3GO, or using triethylene glycol di-2-ethyl butyrate (3GH) and
triethylene glycol di-n-heptanoate (3G7), the ratio
(G'(Tg+80)/G'(Tg+30)) is not greatly different from the ratio
(G'(Tg+80)/G'(Tg+30)) in the case of using 3GO. Further, in the
case that the amount of the plasticizer is 50 to 80 parts by weight
for each 100 parts by weight of the polyvinyl acetal resin, the
ratios (G'(Tg+80)/G'(Tg+30)) are not greatly different from each
other. The ratio (G'(Tg+80)/G'(Tg+30)) measured using a resin film
containing 100 parts by weight of a polyvinyl acetal resin and 60
parts by weight of triethylene glycol di-2-ethyl hexanoate (3GO) as
a plasticizer is not greatly different from the ratio
(G'(Tg+80)/G'(Tg+30)) measured using the first layer 2 itself. The
ratios (G'(Tg+80)/G'(Tg+30)) obtained by the test method A and the
test method B each are preferably 0.65 or higher, and it is more
preferable that the ratio (G'(Tg+80)/G'(Tg+30)) obtained by the
test method B is 0.65 or higher.
[0072] Also, in order to suppress bubble formation in the
intermediate film for laminated glass, the polyvinyl acetal resin
contained in the first layer 2 is preferably obtained by
acetalization of a polyvinyl alcohol resin with an average degree
of polymerization exceeding 3,000. In this case, the ratio
(G'(Tg+80)/G'(Tg+30)) is not necessarily 0.65 or higher, but is
preferably 0.65 or higher. From the viewpoint of further
suppressing bubble formation and bubble growth in a laminated
glass, the amount of the plasticizer is preferably 40 parts by
weight or more for each 100 parts by weight of the polyvinyl acetal
resin obtained by acetalizing a polyvinyl alcohol resin with an
average degree of polymerization exceeding 3,000 in the first layer
2. In addition, from the viewpoint of further suppressing bubble
formation and bubble growth in a laminated glass, the hydroxy group
content is preferably 30 mol % or lower in the polyvinyl acetal
resin obtained by acetalizing a polyvinyl alcohol resin with an
average degree of polymerization exceeding 3,000 in the first layer
2.
[0073] From the viewpoint of further improving the sound-insulating
property of a laminated glass, the amount of the plasticizer is
preferably 40 parts by weight or more, more preferably 50 parts by
weight or more, still more preferably 55 parts by weight or more,
and particularly preferably 60 parts by weight or more, for each
100 parts by weight of the polyvinyl acetal resin in the first
layer 2. Even in the case that the amount of the plasticizer is
large in the first layer 2 as mentioned above, bubble formation and
bubble growth in a laminated glass can be more effectively
suppressed by controlling the hydroxy group contents in the
polyvinyl acetal resins contained in the first layer, the second
layer and the third layer as mentioned above, by controlling the
proportion of the high-molecular-weight component X with an
absolute molecular weight of 1,000,000 or higher or the proportion
of the high-molecular-weight component Y with a molecular weight y
of 1,000,000 or higher, or by controlling the ratio
(G'(Tg+80)/G'(Tg+30)).
[0074] The following will describe the details of the first layer,
the second layer and the third layer forming the intermediate film
for laminated glass of the present invention and the details of the
polyvinyl acetal resins and the plasticizers contained in the first
layer, the second layer and the third layer.
[0075] (Thermoplastic Resin)
[0076] The polyvinyl acetal resin contained in the first layer
(hereinafter, also referred to as a polyvinyl acetal resin (1)) is
not particularly limited as long as the degree of acetylation
(acetyl group amount) exceeds 30 mol %. The second layer preferably
contains a thermoplastic resin, and more preferably contains a
polyvinyl acetal resin (hereinafter, also referred to as a
polyvinyl acetal resin (2)). The third layer preferably contains a
thermoplastic resin, and more preferably contains a polyvinyl
acetal resin (hereinafter, also referred to as a polyvinyl acetal
resin (3)). If the thermoplastic resins contained in the second
layer and the third layer are the polyvinyl acetal resin (2) and
the polyvinyl acetal resin (3), the adhesive forces between the
second layer and the third layer and the respective components of
laminated glass become sufficiently high.
[0077] Examples of the thermoplastic resin include polyvinyl acetal
resin, ethylene/vinyl acetate copolymerized resin, ethylene/acryl
copolymerized resin, polyurethane resin, and polyvinyl alcohol
resin. Thermoplastic resins other than these may be used.
[0078] The degree of acetylation of the polyvinyl acetal resin (1)
exceeds 30 mol %. A preferable lower limit thereof is 30.5 mol %, a
more preferable lower limit is 32 mol %, a still more preferable
lower limit is 35 mol %, and a particularly preferable lower limit
is 40 mol %, whereas a preferable upper limit is 90 mol %, a still
more preferable upper limit is 80 mol %, a particularly preferable
upper limit is 70 mol %, and a most preferable upper limit is 50
mol %. If the degree of acetylation is not lower than the lower
limit, the sound-insulating property of an intermediate film and a
laminated glass is high. As the degree of acetylation is not lower
than the lower limit, the compatibility between the polyvinyl
acetal resin (1) and the plasticizer may be high.
[0079] The degree of acetylation of each of the polyvinyl acetal
resin (2) and the polyvinyl acetal resin (3) is preferably lower
than the degree of acetylation of the polyvinyl acetal resin (1).
As the degree of acetylation of each of the polyvinyl acetal resin
(2) and the polyvinyl acetal resin (3) is lower than the degree of
acetylation of the polyvinyl acetal resin (1), the penetration
resistance of a laminated glass can be further improved.
[0080] The degree of acetylation of each of the polyvinyl acetal
resin (2) and the polyvinyl acetal resin (3) is preferably 0 mol %
or higher, more preferably 0.1 mol % or higher, and still more
preferably 0.5 mol % or higher, whereas preferably 30 mol % or
lower, more preferably 20 mol % or lower, still more preferably 10
mol % or lower, particularly preferably 5 mol % or lower, and most
preferably 3 mol % or lower. If the degree of acetylation is not
higher than the upper limit, the penetration resistance of an
intermediate film and a laminated glass may be high. Further, if
the degree of acetylation is not higher than the upper limit, bleed
out of the plasticizer can be suppressed.
[0081] If the degree of acetylation of each of the polyvinyl acetal
resin (2) and the polyvinyl acetal resin (3) is 3 mol % or lower,
the mechanical properties of an intermediate film may be further
improved. As a result, the penetration resistance of a laminated
glass can be further improved.
[0082] The degree of acetylation is a value of mole fraction in
terms of percentage (mol %) obtained by subtracting the amount of
ethylene groups bonded with acetal groups and the amount of
ethylene groups bonded with hydroxy groups from the total amount of
ethylene groups in the main chain, and then dividing this value by
the total amount of ethylene groups in the main chain. The amount
of ethylene groups bonded with acetal groups can be measured in
conformity with JIS K6728 "Testing Methods for Polyvinyl Butyral",
for example.
[0083] The difference between the degree of acetylation of the
polyvinyl acetal resin (1) and the degree of acetylation of the
polyvinyl acetal resin (2), and the difference between the degree
of acetylation of the polyvinyl acetal resin (1) and the degree of
acetylation of the polyvinyl acetal resin (3) each are preferably
10 mol % or higher, and more preferably 20 mol % or higher, whereas
preferably 50 mol % or lower, and more preferably 30 mol % or
lower. If the difference between the degree of acetylation of the
polyvinyl acetal resin (1) and that of each of the polyvinyl acetal
resin (2) and the polyvinyl acetal resin (3) is not lower than the
lower limit and not higher than the upper limit, the
sound-insulating property and the penetration resistance of an
intermediate film and a laminated glass can be further
improved.
[0084] The polyvinyl acetal resin (1), polyvinyl acetal resin (2)
and the polyvinyl acetal resin (3) can be produced by, for example,
acetalizing polyvinyl alcohol with an aldehyde. The polyvinyl
alcohol can be obtained by, for example, saponifying polyvinyl
acetate. The degree of saponification of the polyvinyl alcohol is
generally within a range of 70 to 99.9 mol %, and it is preferably
within a range of 75 to 99.8 mol %, and more preferably 80 to 99.8
mol %.
[0085] The average degree of polymerization of the polyvinyl
alcohol for obtaining each of the polyvinyl acetal resin (1),
polyvinyl acetal resin (2) and the polyvinyl acetal resin (3) is
preferably 200 or higher, more preferably 500 or higher, still more
preferably 1,600 or higher, particularly preferably 2,600 or
higher, and most preferably 2,700 or higher, whereas preferably
5,000 or lower, more preferably 4,000 or lower, and still more
preferably 3,500 or lower. If the average degree of polymerization
is not lower than the lower limit, the penetration resistance of a
laminated glass can be further improved. If the average degree of
polymerization is not higher than the upper limit, an intermediate
film can be easily formed.
[0086] From the viewpoint of further improving the penetration
resistance of a laminated glass, the average degree of
polymerization of the polyvinyl alcohol is particularly preferably
2,700 or higher and 5,000 or lower.
[0087] From the viewpoint of further suppressing bubble formation
and bubble growth in a laminated glass, with respect to the average
degree of polymerization of the polyvinyl alcohol resin for
obtaining the polyvinyl acetal resin (1) contained in the first
layer, a preferable lower limit is 3,010, a preferable lower limit
is 3,050, a preferable lower limit is 3,500, a preferable lower
limit is 3,600, a preferable lower limit is 4,000, and a preferable
lower limit is 4,050, whereas a preferable upper limit is 7,000, a
preferable upper limit is 6,000, a preferable upper limit is 5,000,
a preferable upper limit is 4,900, and a preferable upper limit is
4,500. In particular, because bubble formation and bubble growth in
a laminated glass can be further suppressed, the sound-insulating
property of a laminated glass can be sufficiently improved, and an
intermediate film can be easily formed, the average degree of
polymerization of the polyvinyl alcohol resin for obtaining the
polyvinyl acetal resin (1) contained in the first layer is
preferably 3,010 or higher, and more preferably 3,020 or higher,
whereas preferably 4,000 or lower, more preferably lower than
4,000, still more preferably 3,800 or lower, particularly
preferably 3,600 or lower, and most preferably 3,500 or lower.
[0088] The polyvinyl acetal resin (2) and the polyvinyl acetal
resin (3) contained in the second layer and the third layer,
respectively, can be produced by acetalizing a polyvinyl alcohol
resin. With respect to the average degree of polymerization of the
polyvinyl alcohol resin for obtaining the polyvinyl acetal resin
(2) and the polyvinyl acetal resin (3) contained in the second
layer and the third layer, a preferable lower limit is 200, a more
preferable lower limit is 500, a still more preferable lower limit
is 1,000, and a particularly preferable lower limit is 1,500,
whereas a preferable upper limit is 4,000, a more preferable upper
limit is 3,500, a still more preferable upper limit is 3,000, and a
particularly preferable upper limit is 2,500. If the average degree
of polymerization satisfies the above preferable lower limit, the
penetration resistance of a laminated glass can be further
improved. If the average degree of polymerization satisfies the
above preferable upper limit, an intermediate film can be easily
formed.
[0089] The average degree of polymerization of the polyvinyl
alcohol resin for obtaining the polyvinyl acetal resin (1)
contained in the first layer is preferably higher than the average
degree of polymerization of the polyvinyl alcohol resin for
obtaining the polyvinyl acetal resin (2) and the polyvinyl acetal
resin (3) contained in the second layer and the third layer,
preferably by 500 or higher, preferably by 800 or higher, more
preferably by 1,000 or higher, still more preferably by 1,300 or
higher, and particularly preferably 1,800 or higher.
[0090] The average degree of polymerization of the polyvinyl
alcohol can be determined in conformity with JIS K6726 "Testing
methods for polyvinyl alcohol".
[0091] The carbon number of the acetal group contained in the
polyvinyl acetal resin is not particularly limited. The aldehyde to
be used upon producing the polyvinyl acetal resin is not
particularly limited. The carbon number of the acetal group in the
polyvinyl acetal resin is preferably 3 to 5, and more preferably 3
or 4. If the carbon number of the acetal group in the polyvinyl
acetal resin is 3 or greater, the glass transition temperature of
an intermediate film is sufficiently low, so that the
sound-insulating property against structure-borne sound at low
temperatures can be further improved.
[0092] The aldehyde is not particularly limited. In general, a
C1-C10 aldehyde is suitably used as the aforementioned aldehyde.
Examples of the C1-C10 aldehyde include propionaldehyde, n-butyl
aldehyde, isobutyl aldehyde, n-valeraldehyde, 2-ethylbutyl
aldehyde, n-hexyl aldehyde, n-octyl aldehyde, n-nonyl aldehyde,
n-decyl aldehyde, formaldehyde, acetaldehyde, and benzaldehyde. In
particular, propionaldehyde, n-butyl aldehyde, isobutyl aldehyde,
n-hexyl aldehyde, or n-valeraldehyde is preferable;
propionaldehyde, n-butyl aldehyde, or isobutyl aldehyde is more
preferable; and n-butyl aldehyde is still more preferable. Each of
the aldehydes may be used alone, or two or more of these may be
used in combination.
[0093] The polyvinyl acetal resin is preferably a polyvinyl butyral
resin. The intermediate film for laminated glass of the present
invention preferably contains a polyvinyl butyral resin as each of
the polyvinyl acetal resins contained in the first layer, the
second layer and the third layer. The polyvinyl butyral resin can
be easily synthesized. Further, use of polyvinyl butyral resin
allows an intermediate film to more suitably exert its adhesive
force to components for laminated glass. In addition, properties
such as the light resistance and weather resistance can be further
improved.
[0094] The hydroxy group content (hydroxy group amount) in the
polyvinyl acetal resin (1) is preferably 45 mol % or lower, more
preferably 35 mol % or lower, still more preferably 30 mol % or
lower, much more preferably 25 mol % or lower, particularly
preferably 20 mol % or lower, and most preferably 15 mol % or
lower. If the hydroxy group content is not higher than the upper
limit, the sound-insulating property of a laminated glass can be
further improved. In addition, the flexibility of an intermediate
film can be improved and the intermediate film can be easily
handled. From the viewpoint of further improving the
sound-insulating property in a high frequency range of a laminated
glass, the hydroxy group content in the polyvinyl acetal resin (1)
is preferably as low as possible. The hydroxy group content in the
polyvinyl acetal resin (1) can be 0 mol %.
[0095] The hydroxy group content (hydroxy group amount) in each of
the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3)
is preferably higher than the hydroxy group content in the
polyvinyl acetal resin (1). The hydroxy group content (hydroxy
group amount) in each of the polyvinyl acetal resin (2) and the
polyvinyl acetal resin (3) is preferably 20 mol % or higher, more
preferably 25 mol % or higher, and still more preferably 30 mol %
or higher, whereas preferably 50 mol % or lower, more preferably 45
mol % or lower, still more preferably 40 mol % or lower, and
particularly preferably 35 mol % or lower. If the hydroxy group
content is not lower than the lower limit, the penetration
resistance of a laminated glass can be further improved. If the
hydroxy group content is not higher than the upper limit, bleed out
of a plasticizer is less likely to occur. In addition, the
flexibility of an intermediate film can be improved and the
intermediate film may be easily handled.
[0096] Each of the hydroxy group contents in the polyvinyl acetal
resin (1), the polyvinyl acetal resin (2) and the polyvinyl acetal
resin (3) is a value of mole fraction in terms of percentage (mol
%) obtained by dividing the amount of ethylene groups bonded with
hydroxy groups by the total amount of ethylene groups in the main
chain. The amount of ethylene groups bonded with hydroxy groups can
be determined by measuring the amount of ethylene groups bonded
with the hydroxy groups in polyvinyl alcohol as a material in
conformity with JIS K6726 "Testing Methods for Polyvinyl Alcohol",
for example.
[0097] The degree of acetalization of the polyvinyl acetal resin
(1) (in the case of polyvinyl butyral resin, degree of
butyralization) is preferably 20 mol % or higher, more preferably
25 mol % or higher, and still more preferably 30 mol % or higher,
whereas preferably 65 mol % or lower, more preferably 60 mol % or
lower, and still more preferably 55 mol % or lower. If the degree
of acetalization is not lower than the lower limit, the
compatibility between the polyvinyl acetal resin (1) and the
plasticizer can be improved, and bleed out of the plasticizer can
be suppressed. If the degree of acetalization is not higher than
the upper limit, the reaction time required for producing a
polyvinyl acetal resin can be shortened.
[0098] The degree of acetalization of each of the polyvinyl acetal
resin (2) and the polyvinyl acetal resin (3) (in the case of
polyvinyl butyral resin, degree of butyralization) is preferably 55
mol % or higher, more preferably 60 mol % or higher, and still more
preferably 63 mol % or higher, whereas preferably 85 mol % or
lower, more preferably 75 mol % or lower, and still more preferably
70 mol % or lower. If the degree of acetalization is not lower than
the lower limit, the compatibility between the polyvinyl acetal
resin (2) and the polyvinyl acetal resin (3) and the plasticizer
can be improved. If the degree of acetalization is not higher than
the upper limit, the reaction time required for producing a
polyvinyl acetal resin can be shortened.
[0099] The degree of aetalization is a value of mole fraction in
terms of percentage (mol %) obtained by dividing the amount of
ethylene groups bonded with acetal groups by the total amount of
ethylene groups in the main chain.
[0100] The degree of acetalization can be calculated by measuring
the degree of acetylation (degree of acetylation) and the hydroxy
group content (vinyl alcohol amount), calculating the molar
fractions thereof based on the obtained measurement results, and
subtracting the degree of acetylation and the hydroxy group content
from 100 mol %, according to the method in conformity with JIS
K6728 "Testing Methods for Polyvinyl Butyral".
[0101] The degree of acetalization can be calculated by measuring
the degree of acetylation (degree of acetylation) and the hydroxy
group content (vinyl alcohol amount), calculating the molar
fractions thereof based on the obtained measurement results, and
subtracting the degree of acetylation and the hydroxy group content
from 100 mol %, according to the method in conformity with JIS
K6728 "Testing Methods for Polyvinyl Butyral".
[0102] In the case that the polyvinyl acetal resin is a polyvinyl
butyral resin, the degree of acetalization (degree of
butyralization) and the degree of acetylation can be calculated
based on the measurement results according to the method in
conformity with JIS K6728 "Testing Methods for Polyvinyl Butyral"
or ASTM D1396-92. It is preferable to measure the values according
to the method in conformity with ASTM D1396-92.
[0103] With respect to the weight average molecular weight of each
of the polyvinyl acetal resin (1), the polyvinyl acetal resin (2)
and the polyvinyl acetal resin (3), the lower limit thereof is
preferably 100,000, and more preferably 300,000, whereas the upper
limit thereof is preferably 10,000,000, and more preferably
5,000,000. If the weight average molecular weight of the polyvinyl
acetal resin is not higher than the preferable lower limit, the
strength of an intermediate film may be low. If the weight average
molecular weight of the polyvinyl acetal resin exceeds the
preferable upper limit, the strength of an intermediate film to be
obtained may be too high. The weight average molecular weight
herein indicates a weight average molecular weight in terms of
polystyrene by gel permeation chromatography (GPC) measurement.
[0104] The aforementioned weight average molecular weight and
number average molecular weight are a weight average molecular
weight and a number average molecular weight in terms of
polystyrene obtained by gel permeation chromatography (GPC)
measurement. For example, in order to measure the weight average
molecular weight and number average molecular weight in terms of
polystyrene, polystyrene standard samples with known molecular
weights are subjected to GPC measurement. As the polystyrene
standard samples ("Shodex Standard SM-105", "Shodex Standard
SH-75", SHOWA DENKO K.K.) are used 14 samples with the respective
weight average molecular weights of 580, 1,260, 2,960, 5,000,
10,100, 21,000, 28,500, 76,600, 196,000, 630,000, 1,130,000,
2,190,000, 3,150,000, and 3,900,000. Molecular weights are plotted
with respect to the corresponding elution times indicated by the
peak tops of the peaks of the respective standard samples, and the
obtained approximate straight line is used as a calibration curve.
A multilayer intermediate film is left in a constant temperature
and humidity facility (humidity: 30% (.+-.3%), temperature:
23.degree. C.) for one month, and then the surface layers (the
second layer and the third layer) and the intermediate layer (the
first layer) are separated. The separated first layer (intermediate
layer) is dissolved in tetrahydrofuran (THF) to prepare a 0.1 wt %
solution. The obtained solution is analyzed using a GPC device, and
thereby the weight average molecular weight and the number average
molecular weight are measured. The GPC device used for analyzing
the weight average molecular weight and the number average
molecular weight may be a GPC device (Hitachi High-Technologies
Corp., RI: L2490, auto-sampler: L-2200, pump: L-2130, column oven:
L-2350, columns: GL-A120-S and GL-A100MX-S in series) connected
with a light scattering detector for GPC (VISCOTEK, Model 270
(RALS+VISCO)).
[0105] (Method of Producing Polyvinyl Acetal Resin Containing
High-Molecular-Weight Component X with Absolute Molecular Weight of
1,000,000 or Higher or High-Molecular-Weight Component Y with
Molecular Weight y of 1,000,000 or Higher)
[0106] The following will describe in detail the method of
producing a polyvinyl acetal resin containing a
high-molecular-weight component X with an absolute molecular weight
of 1,000,000 or higher or a high-molecular-weight component Y with
a molecular weight y of 1,000,000 or higher.
[0107] First, polyvinyl alcohol is prepared. The polyvinyl alcohol
can be obtained by saponifying polyvinyl acetate, for example. The
degree of saponification of the polyvinyl alcohol is usually within
the range of 70 to 99.9 mol %, preferably within the range of 75 to
99.8 mol %, and more preferably within the range of 80 to 99.8 mol
%.
[0108] With respect to the degree of polymerization of the
polyvinyl alcohol, a preferable lower limit is 200, a more
preferable lower limit is 500, a still more preferable lower limit
is 1,000, and a particularly preferable lower limit is 1,500,
whereas a preferable upper limit is 3,000, a more preferable upper
limit is 2,900, a still more preferable upper limit is 2,800, and a
particularly preferable upper limit is 2,700. If the degree of
polymerization is too low, the penetration resistance of a
laminated glass tends to be low. If the degree of polymerization is
too high, it may be difficult to form an intermediate film.
[0109] Next, the polyvinyl alcohol and an aldehyde are reacted
using a catalyst, and thereby the polyvinyl alcohol is acetalized.
At this time, a solution containing the polyvinyl alcohol may be
used. Examples of the solvent used for the solution containing the
polyvinyl alcohol include water.
[0110] The method for producing the polyvinyl acetal resin
contained in the first layer is preferably a production method in
which the polyvinyl alcohol and an aldehyde are reacted using a
catalyst so that the polyvinyl alcohol is acetalized, and thereby a
polyvinyl acetal resin is obtained.
[0111] The method of producing the first layer preferably comprises
a step of preparing a polyvinyl acetal resin by reacting a
polyvinyl alcohol and an aldehyde using a catalyst so that the
polyvinyl alcohol is acetalized, and a step of preparing the first
layer using a mixture of the obtained polyvinyl acetal resin and a
plasticizer. In this step of preparing the first layer, or after
the first layer is obtained, a multilayer intermediate film can be
obtained by laminating a second layer and, if necessary, laminating
a third layer, on the first layer. Alternatively, a multilayer
intermediate film can be produced by co-extruding the first layer
and the second layer, or a multilayer intermediate film can be
produced by co-extruding the first layer, the second layer, and the
third layer.
[0112] The aldehyde is not particularly limited. A suitable
aldehyde is commonly a C1-C10 aldehyde. Examples of the C1-C10
aldehyde include propionaldehyde, n-butyl aldehyde, isobutyl
aldehyde, n-valeraldehyde, 2-ethylbutyl aldehyde, n-hexyl aldehyde,
n-octyl aldehyde, n-nonyl aldehyde, n-decyl aldehyde, formaldehyde,
acetaldehyde, and benzaldehyde. In particular, n-butyl aldehyde,
n-hexyl aldehyde, or n-valeraldehyde is preferable, and n-butyl
aldehyde is more preferable. Each of the aldehydes may be used
alone, or two or more of these may be used in combination.
[0113] From the viewpoint of easily obtaining a polyvinyl acetal
resin containing high-molecular-weight component X with an absolute
molecular weight of 1,000,000 or higher or high-molecular-weight
component Y with a molecular weight y of 1,000,000 or higher in the
aforementioned specific ratio, for example, the following methods
can be exemplified: a method of adding a cross-linker such as
dialdehyde for cross-linking the main chains of adjacent polyvinyl
alcohols before or in the middle of the acetalizing reaction with
an aldehyde; a method of adding an excessive amount of aldehyde to
proceed the acetalizing reaction between the molecules; and a
method of adding a polyvinyl alcohol with a high degree of
polymerization. Each of these methods may be used alone, or two or
more of these may be used in combination.
[0114] The catalyst is preferably an acid catalyst. Examples of the
acid catalyst include nitric acid, hydrochloric acid, sulfuric
acid, phosphoric acid, and para-toluenesulfonic acid.
[0115] The molecular weight in terms of polystyrene is a molecular
weight in terms of polystyrene by gel permeation chromatography
(GPC) measurement. The proportion (%) of the high-molecular-weight
component Y with a molecular weight y of 1,000,000 or higher in the
polyvinyl acetal resin is calculated from the ratio of the area
corresponding to a region where the molecular weight y is 1,000,000
or higher among the peak area detected by an RI detector upon
measuring the molecular weight in terms of polystyrene by GPC on
the polyvinyl acetal resin. The peak area means an area between the
peak and the baseline of the component to be measured.
[0116] The molecular weight in terms of polystyrene can be measured
as follows, for example.
[0117] In order to measure the molecular weight in terms of
polystyrene standard, polystyrene standard samples with known
molecular weights are subjected to GPC measurement. As the
polystyrene standard samples ("Shodex Standard SM-105", "Shodex
Standard SH-75", SHOWA DENKO K.K.) are used 14 samples with the
respective weight average molecular weights of 580, 1,260, 2,960,
5,000, 10,100, 21,000, 28,500, 76,600, 196,000, 630,000, 1,130,000,
2,190,000, 3,150,000, and 3,900,000. Weight average molecular
weights are plotted with respect to the corresponding elution times
indicated by the peak tops of the peaks of the respective standard
samples, and the obtained approximate straight line is used as a
calibration curve. In the case of measuring the proportion (%) of
the high-molecular-weight component Y with the molecular weight y
of 1,000,000 or higher in the polyvinyl acetal resin contained in
the intermediate layer in a multilayer intermediate film having a
surface layer, the intermediate layer, and a surface layer
laminated in the stated order, for example, the multilayer
intermediate film is left in a constant temperature and humidity
facility (humidity: 30% (.+-.3%), temperature: 23.degree. C.) for
one month, and then the surface layers and the intermediate layer
are separated. The separated intermediate layer is dissolved in
tetrahydrofuran (THF) to prepare a 0.1 wt % solution. The obtained
solution is analyzed using a GPC device, and thereby the peak area
of the polyvinyl acetal resin in the intermediate layer is
measured. Next, based on the elution time and the calibration curve
of the polyvinyl acetal resin contained in the intermediate layer,
the area corresponding to a region where the molecular weight in
terms of polystyrene of the polyvinyl acetal resin contained in the
intermediate layer is 1,000,000 or higher is calculated. By
representing in percentage (%) a value obtained by dividing the
area corresponding to a region where the molecular weight in terms
of polystyrene of the polyvinyl acetal resin contained in the
intermediate layer is 1,000,000 or higher by the peak area of the
polyvinyl acetal resin contained in the intermediate layer, the
proportion (%) of the high-molecular-weight component Y with the
molecular weight y of 1,000,000 or higher in the polyvinyl acetal
resin can be calculated. For example, the molecular weight in terms
of polystyrene can be measured using a gel permeation
chromatography (GPC) device (Hitachi High-Technologies Corp., RI:
L2490, auto-sampler: L-2200, pump: L-2130, column oven: L-2350,
columns: GL-A120-S and GL-A100MX-9 in series).
[0118] (Plasticizer)
[0119] The first layer contains a plasticizer (hereinafter, also
referred to as a plasticizer (1)). The second layer preferably
contains a plasticizer (hereinafter, also referred to as a
plasticizer (2)). The third layer preferably contains a plasticizer
(hereinafter, also referred to as a plasticizer (3)). The
plasticizer (1), the plasticizer (2) and the plasticizer (3)
contained in the first layer, the second layer and the third layer
are not particularly limited. Conventionally known plasticizers can
be used as the plasticizer (1), the plasticizer (2) and the
plasticizer (3). Each of the plasticizer (1), the plasticizer (2)
and the plasticizer (3) may be used alone, or two or more of these
may be used in combination.
[0120] Examples of the plasticizer (1), the plasticizer (2) and the
plasticizer (3) include organic ester plasticizers such as
monobasic organic acid esters and polybasic organic acid esters,
and phosphate plasticizers such as organophosphate plasticizers and
organophosphite plasticizers. Preferable among these are organic
ester plasticizers. The plasticizers are preferably liquid
plasticizers.
[0121] The monobasic organic acid esters are not particularly
limited. Examples thereof include glycol esters obtainable by
reaction of a glycol and a monobasic organic acid, and esters of
triethylene glycol or tripropylene glycol and a monobasic organic
acid. Examples of the glycol include triethylene glycol,
tetraethylene glycol, and tripropylene glycol. Examples of the
monobasic organic acid include butyric acid, isobutyric acid,
caproic acid, 2-ethylbutyric acid, heptanoic acid, n-octylic acid,
2-ethylhexylic acid, n-nonylic acid, and decylic acid.
[0122] The polybasic organic acid esters are not particularly
limited. Examples thereof include ester compounds of a polybasic
organic acid and a C4-C8 linear or branched alcohol. Examples of
the polybasic organic acid include adipic acid, sebacic acid, and
azelaic acid.
[0123] The organic ester plasticizers are not particularly limited.
Examples thereof include triethylene glycol di-2-ethyl butyrate,
triethylene glycol di-2-ethyl hexanoate, triethylene glycol
dicaprylate, triethylene glycol di-n-octanoate, triethylene glycol
di-n-heptanoate, tetraethylene glycol di-n-heptanoate, dibutyl
sebacate, dioctyl azelate, dibutyl carbitol adipate, ethylene
glycol di-2-ethyl butyrate, 1,3-propylene glycol di-2-ethyl
butyrate, 1,4-butyrene glycol di-2-ethyl butyrate, diethylene
glycol di-2-ethyl butyrate, diethylene glycol di-2-ethyl hexanoate,
dipropylene glycol di-2-ethyl butyrate, triethylene glycol
di-2-ethyl pentanoate, tetraethylene glycol di-2-ethyl butyrate,
diethylene glycol dicaprylate, dihexyl adipate, dioctyl adipate,
hexyl cyclohexyl adipate, a mixture of heptyl adipate and nonyl
adipate, diisononyl adipate, diisodecyl adipate, heptylnonyl
adipate, dibutyl sebacate, oil-modified alkyd sebacate, and a
mixture of a phosphate and an adipate. Organic ester plasticizers
other than these may also be used.
[0124] The organophosphate plasticizers are not particularly
limited. Examples thereof include tributoxyethyl phosphate,
isodecylphenyl phosphate, and triisopropyl phosphate.
[0125] The plasticizer (1), the plasticizer (2) and the plasticizer
(3) each are preferably a diester plasticizer represented by the
following formula (1).
##STR00001##
[0126] In the formula (1), R1 and R2 each represent a C3-C10
organic group; R3 represents an ethylene group, an isopropylene
group, or an n-propylene group; and p is an integer of 3 to 10. In
the formula (1), R1 and R2 each are preferably a C5-C10 alkyl
group.
[0127] The plasticizers preferably include at least one of
triethylene glycol di-2-ethyl hexanoate (3GO), triethylene glycol
dibutyrate (3 GB), dibutyl adipate, and triethylene glycol
di-2-ethyl butyrate (3GH), and more preferably include triethylene
glycol di-2-ethyl hexanoate or triethylene glycol dibutyrate.
[0128] In the first layer, the amount of the plasticizer (1) is
preferably 25 to 60 parts by weight for each 100 parts by weight of
the polyvinyl acetal resin (1). The amount of the plasticizer (1)
for each 100 parts by weight of the polyvinyl acetal resin (1) is
more preferably parts by weight or more, and still more preferably
40 parts by weight or more, whereas more preferably 55 parts by
weight or less, and still more preferably 50 parts by weight or
less. If the amount of the plasticizer (1) is not lower than the
lower limit, the flexibility of an intermediate film may be high,
and thereby the intermediate film can be easily handled. If the
amount of the plasticizer (1) is not higher than the upper limit,
the transparency of an intermediate film can be higher.
[0129] In the second layer (2), the amount of the plasticizer (2)
is preferably 15 to 45 parts by weight for each 100 parts by weight
of the polyvinyl acetal resin (2). In addition, in the third layer
(3), the amount of the plasticizer (3) is preferably 15 to 45 parts
by weight for each 100 parts by weight of the polyvinyl acetal
resin (3). The amount of each of the plasticizer (2) and the
plasticizer (3) for each 100 parts by weight of the polyvinyl
acetal resin (2) and the polyvinyl acetal resin (3) is more
preferably 20 parts by weight or more, whereas more preferably 40
parts by weight or less. If each of the amounts of the plasticizer
(2) and the plasticizer (3) is not lower than the lower limit, the
flexibility of an intermediate film may be high, and thereby the
intermediate film can be easily handled. If each of the amounts of
the plasticizer (2) and the plasticizer (3) is not higher than the
upper limit, the penetration resistance of an intermediate film can
be higher.
[0130] The amount of the plasticizer (2) (hereinafter, also
referred to as an amount (2)) for each 100 parts by weight of the
polyvinyl acetal resin (2) in the second layer is preferably less
than the amount of the plasticizer (1) (hereinafter, also referred
to as an amount (1)) for each 100 parts by weight of the polyvinyl
acetal resin (1) in the first layer. Also, the amount of the
plasticizer (3) (hereinafter, also referred to as an amount (3))
for each 100 parts by weight of the polyvinyl acetal resin (3) in
the third layer is preferably less than the amount of the
plasticizer (1) (hereinafter, also referred to as an amount (1))
for each 100 parts by weight of the polyvinyl acetal resin (1) in
the first layer. As the amount (2) and the amount (3) each are less
than the amount (1), the penetration resistance of a laminated
glass can be higher.
[0131] With respect to the difference between the amount (1) and
each of the amount (2) and the amount (3), a preferable lower limit
is 1 part by weight, a more preferable lower limit is 5 parts by
weight, a still more preferable lower limit is 10 parts by weight,
a particularly preferable lower limit is 15 parts by weight, and a
most preferable lower limit is 20 parts by weight, whereas a
preferable upper limit is 40 parts by weight, a more preferable
upper limit is 35 parts by weight, a still more preferable upper
limit is 30 parts by weight, and a particularly preferable upper
limit is 25 parts by weight. If the difference between the amount
(1) and each of the amount (2) and the amount (3) is not lower than
the lower limit, the sound-insulating property of a laminated glass
can be higher, whereas if the difference is not higher than the
upper limit, the penetration resistance of a laminated glass can be
higher. The difference between the amount (1) and each of the
amount (2) and the amount (3) is a value obtained by subtracting
either the amount (2) or the amount (3) from the amount (1).
[0132] (Other Components)
[0133] The intermediate film for laminated glass of the present
invention may contain additives such as an ultraviolet absorber, an
antioxidant, a photostabilizer, a flame retardant, an antistatic
agent, pigments, dyes, adhesiveness adjuster, an anti-humidity
agent, a fluorescent brightener, and an infrared radiation
absorber, if necessary. Each of these additives may be used alone,
or two or more additives may be used in combination.
[0134] (Intermediate Film for Laminated Glass)
[0135] The thickness of the first layer is preferably within a
range of 0.02 to 1.8 mm. The thickness of the first layer is more
preferably 0.05 m or higher, and still more preferably 0.08 m or
higher, whereas more preferably 0.5 ma or lower, and still more
preferably 0.15 ma or lower. As the first layer has such a
preferable thickness, an intermediate film may not be too thick,
and the sound-insulating property of the intermediate film and a
laminated glass can be further improved.
[0136] The thicknesses of the second layer and the third layer each
are preferably within a range of 0.1 to 1 mm. The thicknesses of
the second layer and the third layer each are more preferably 0.2
mm or higher, and still more preferably 0.3 mm or higher, whereas
more preferably 0.5 mm or lower, and still more preferably 0.4 am
or lower. If the thicknesses of the second layer and the third
layer each are not lower than the lower limit and not higher than
the upper limit, an intermediate film may not be too thick, the
sound-insulating property of the intermediate film and a laminated
glass can be further improved, and bleed out of the plasticizers
can be suppressed.
[0137] In the case that the intermediate film has a laminated
structure of two or more layers, as the ratio of the thickness of
the first layer to the thickness of the intermediate film
((thickness of first layer)/(thickness of intermediate film)) is
smaller and the amount of the plasticizer contained in the first
layer is larger, bubble formation and bubble growth in a laminated
glass is more likely to occur and the bubbles are more likely to
grow. Particularly in the case that the ratio in the intermediate
film is 0.05 or higher and 0.35 or lower, bubble formation and
bubble growth in a laminated glass can be sufficiently suppressed
and the sound-insulating property of a laminated glass can be
further improved even though the amount of the plasticizer for each
100 parts by weight of the polyvinyl acetal resin is large in the
first layer. The ratio ((thickness of first layer)/(thickness of
intermediate film)) is preferably 0.06 or higher, more preferably
0.07 or higher, still more preferably 0.08 or higher, and
particularly preferably 0.1 or higher, whereas preferably 0.3 or
lower, more preferably 0.25 or lower, still more preferably 0.2 or
lower, and particularly preferably 0.15 or lower.
[0138] The thickness of the intermediate film for laminated glass
of the present invention is preferably within a range of 0.1 to 3
mm. The thickness of the intermediate film is more preferably 0.25
mm or higher, whereas more preferably 1.5 mm or lower. If the
thickness of the intermediate film is not lower than the lower
limit, the penetration resistance of the intermediate film and a
laminated glass may be sufficiently high. If the thickness of the
intermediate film is not higher than the upper limit, the
transparency of an intermediate film may be better.
[0139] The method for producing the intermediate film for laminated
glass of the present invention is not particularly limited. Any
conventionally known method may be used as the method for producing
the intermediate film. For example, a polyvinyl acetal resin and a
plasticizer, and other components added as appropriate are kneaded,
and then the kneaded product is formed into an intermediate film. A
production method including extrusion-molding is preferable because
such a method is suitable for continuous production.
[0140] The kneading method is not particularly limited. For
example, a method using an extruder, a plastograph, a kneader, a
Banbury mixer, or a calendar roll may be applied. Preferable among
these is a method using an extruder, and a method using a
twin-screw extruder is more suitable because it is suitable for
continuous production. With respect to the intermediate film for
laminated glass of the present invention, the first layer, the
second layer and the third layer may be separately produced, and
then laminated to provide a multilayer intermediate film, or the
first layer, the second layer and the third layer may be laminated
by co-extrusion to provide an intermediate film.
[0141] Because the producibility of the intermediate film is
excellent, the second layer and the third layer preferably contain
the same polyvinyl acetal resin; the second layer and the third
layer more preferably contain the same polyvinyl acetal resin and
the same plasticizer; and the second layer and the third layer are
still more preferably formed from the same resin composition.
[0142] (Laminated Glass)
[0143] FIG. 2 is a cross-sectional view showing one example of a
laminated glass using the intermediate film for laminated glass
according to one embodiment of the present invention.
[0144] A laminated glass 11 shown in FIG. 2 comprises an
intermediate film 1, a first component for laminated glass 21 and a
second component for laminated glass 22. The intermediate film 1 is
sandwiched between the first component for laminated glass 21 and
the second component for laminated glass 22. The component for
laminated glass 21 is laminated on a first surface 1a of the
intermediate film 1. The component for laminated glass 22 is
laminated on a second surface 1b opposite to the first surface 1a
of the intermediate film 1. The first component for laminated glass
21 is laminated on an outer surface 3a of the second layer 3. The
second component for laminated glass 22 is laminated on an outer
surface 4a of the third layer 4.
[0145] As mentioned above, the laminated glass of the present
invention comprises a first component for laminated glass, a second
component for laminated glass, and an intermediate film sandwiched
between the first component for laminated glass and the second
component for laminated glass, wherein the intermediate film is the
intermediate film for laminated glass of the present invention.
[0146] Examples of the first component for laminated glass and the
second component for laminated glass include glass plates and PET
(polyethylene terephthalate) films. The laminated glass includes
not only a laminated glass in which an intermediate film is
sandwiched between two glass plates, but also a laminated glass in
which an intermediate film is sandwiched between a glass plate and
a PET film, for example. The laminated glass is a laminate
comprising a glass plate, and at least one glass plate is
preferably used.
[0147] Examples of the glass plate include inorganic glass and
organic glass. Examples of the inorganic glass include float plate
glass, heat-absorbing plate glass, heat-reflective plate glass,
polished plate glass, patterned glass, wired glass, linear-wired
glass and green-tinted glass. The organic glass is synthetic resin
glass used instead of inorganic glass. Examples of the organic
glass include polycarbonate plates and poly(meth)acryl resin
plates. Examples of the poly(meth)acryl resin plate include
polymethyl (meth)acrylate plates.
[0148] The thickness of each of the first component for laminated
glass and the second component for laminated glass is not
particularly limited, and it is preferably within a range of 1 to 5
am. In the case that the component for laminated glass is a glass
plate, the thickness of the glass plate is preferably within a
range of 1 to 5 mm. In the case that the component for laminated
glass is a PET film, the thickness of the PET film is preferably
within a range of 0.03 to 0.5 mm.
[0149] The method for producing the laminated glass is not
particularly limited. For example, the intermediate film is
sandwiched between the first component for laminated glass and the
second component for laminated glass, and then passed through a
press roll or put into a rubber bag and decompression-sucked, so
that the air remained between the first component for laminated
glass and the second component for laminated glass and the
intermediate film is removed. Thereafter, the workpiece is
pre-bonded at about 70.degree. C. to 110.degree. C. so that a
laminate is provided. Next, the laminate is put into an autoclave
or pressed so that the laminate is press-bonded at about
120.degree. C. to 150.degree. C. and a pressure of 1 to 1.5 MPa,
and thereby a laminated glass is obtained.
[0150] The laminated glass can be used for automobiles, railway
carriages, aircrafts, ships, buildings, and the like. The laminated
glass can also be used for other applications. The intermediate
film is preferably an intermediate film for buildings or vehicles,
and more preferably for vehicles. The laminated glass is preferably
a laminated glass for buildings or vehicles, and more preferably
for vehicles. The intermediate film and the laminated glass can be
suitably used for electric vehicles using electric motors and
hybrid electric vehicles using internal-combustion engines and
electric motors. The laminated glass can be used for windshields,
side glasses, rear glasses, and roof glasses of automobiles.
[0151] The following will describe the present invention in detail
referring to, but not limited to, examples.
[0152] In the examples and comparative examples, the following
polyvinyl butyral resins (polyvinyl acetal resins) were used. The
degree of butyralization (degree of acetalization), the degree of
acetylation, and the hydroxy group content of each polyvinyl
butyral resin were measured by the method in conformity with ASTM
D1396-92. Also, in the case of measuring the values in conformity
with JIS K6728 "Testing Methods for Polyvinyl Butyral", the same
values were indicated as in the method in conformity with ASTM
D1396-92.
Synthesis Example 1
Synthesis of Polyvinyl Butyral Resin a
[0153] A polyvinyl butyral resin (average degree of polymerization:
3,000) having a degree of acetylation of 0.5 mol %, a degree of
butyralization of 40 mol %, and a hydroxy group content of 59.5 mol
% was dissolved in pyridine. To the dissolved polyvinyl butyral
resin was added 30 mol equivalents of acetic anhydride, and the
mixture was stirred at 80.degree. C. for 120 minutes. The pyridine
was removed, and then the polyvinyl butyral resin was washed with
water and dried. Thereby, a polyvinyl butyral resin a (average
degree of polymerization: 3,000) was obtained. With respect to the
obtained polyvinyl butyral resin a, the degree of acetylation was
30.5 mol %, the degree of butyralization was 40 mol %, and the
hydroxy group content was 29.5 mol %.
Synthesis Example 2
Synthesis of Polyvinyl Butyral Resin b
[0154] A polyvinyl butyral resin (average degree of polymerization:
3,000) having a degree of acetylation of 0.5 mol %, a degree of
butyralization of 35 mol %, and a hydroxy group content of 64.5 mol
% was dissolved in pyridine. To the dissolved polyvinyl butyral
resin was added 39.5 mol equivalents of acetic anhydride, and the
mixture was stirred at 80.degree. C. for 120 minutes. The pyridine
was removed, and then the polyvinyl butyral resin was washed with
water and dried. Thereby, a polyvinyl butyral resin b (average
degree of polymerization: 3,000) was obtained. With respect to the
obtained polyvinyl butyral resin b, the degree of acetylation was
40 mol %, the degree of butyralization was 35 mol %, and the
hydroxy group content was 25 mol %.
Synthesis Example 3
Synthesis of Polyvinyl Butyral Resin c
[0155] A polyvinyl butyral resin (average degree of polymerization:
3,000) having a degree of acetylation of 0.5 mol %, a degree of
butyralization of 25 mol %, and a hydroxy group content of 74.5 mol
% was dissolved in pyridine. To the dissolved polyvinyl butyral
resin was added 49.5 mol equivalents of acetic anhydride, and the
mixture was stirred at 80.degree. C. for 120 minutes. The pyridine
was removed, and then the polyvinyl butyral resin was washed with
water and dried. Thereby, a polyvinyl butyral resin c (average
degree of polymerization: 3,000) was obtained. With respect to the
obtained polyvinyl butyral resin c, the degree of acetylation was
50 mol %, the degree of butyralization was 25 mol %, and the
hydroxy group content was 25 mol %.
Synthesis Example 4
Synthesis of Polyvinyl Butyral Resin d
[0156] To 2,910 g of pure water was added 190 g of polyvinyl
alcohol with a degree of polymerization of 1,700, and then the
mixture was heated so that the polyvinyl alcohol was dissolved into
the pure water. The temperature of the solution was controlled to
12.degree. C. To the solution were added 201 g of 35 wt %
hydrochloric acid and 134 g of n-butyl aldehyde, and a polyvinyl
butyral resin was precipitated. Thereafter, the reaction system was
kept at 50.degree. C. for 4 hours, and the reaction was finished.
The resin was washed with excess water so that unreacted n-butyl
aldehyde was washed away. Further, the hydrochloric acid catalyst
was neutralized and the salt was removed, and then the product was
dried. Thereby, a polyvinyl butyral resin d was obtained. With
respect to the obtained polyvinyl butyral resin d, the degree of
acetylation was 1 mol %, the degree of butyralization was 68.5 mol
%, and the hydroxy group content was 30.5 mol %.
Synthesis Example 5
Synthesis of Polyvinyl Butyral Resin e
[0157] To 2,890 g of pure water was added 191 g of polyvinyl
alcohol with a degree of polymerization of 3,000, and then the
mixture was heated so that the polyvinyl alcohol was dissolved into
the pure water. The temperature of the solution was controlled to
12.degree. C. To the solution were added 201 g of 35 wt %
hydrochloric acid and 150 g of n-butyl aldehyde, and a polyvinyl
butyral resin was precipitated. Thereafter, the reaction system was
kept at 50.degree. C. for 5 hours, and the reaction was finished.
The resin was washed with excess water so that unreacted n-butyl
aldehyde was washed away. Further, the hydrochloric acid catalyst
was neutralized and the salt was removed, and then the product was
dried. Thereby, a polyvinyl butyral resin e was obtained. With
respect to the obtained polyvinyl butyral resin e, the degree of
acetylation was 12.8 mol %, the degree of butyralization was 63.5
mol %, and the hydroxy group content was 23.7 mol %.
Synthesis Example 6
Synthesis of Polyvinyl Butyral Resin f
[0158] A polyvinyl butyral resin (average degree of polymerization:
3,000) having a degree of acetylation of 13 mol %, a degree of
butyralization of 59 mol %, and a hydroxy group content of 28 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 22 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin f was obtained. With
respect to the obtained polyvinyl butyral resin f, the degree of
acetylation was 35 mol %, the degree of butyralization was 59 mol
%, and the hydroxy group content was 6 mol %.
Synthesis Example 7
Synthesis of Polyvinyl Butyral Resin g
[0159] A polyvinyl butyral resin (average degree of polymerization:
3,000) having a degree of acetylation of 20 mol %, a degree of
butyralization of 45 mol %, and a hydroxy group content of 35 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 20 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin g was obtained. With
respect to the obtained polyvinyl butyral resin g, the degree of
acetylation was 40 mol %, the degree of butyralization was 45 mol
%, and the hydroxy group content was 15 mol %.
Synthesis Example 8
Synthesis of Polyvinyl Butyral Resin h
[0160] A blended product (weight ratio is 1:1) of a polyvinyl
butyral resin (average degree of polymerization: 2,800) with a
degree of acetylation of 20 mol %, a degree of butyralization of 58
mol %, and a hydroxy group content of 22 mol % and a polyvinyl
butyral resin (average degree of polymerization: 4,000) with a
degree of acetylation of 20 mol %, a degree of butyralization of 58
mol %, and a hydroxy group content of 22 mol % was dissolved in
pyridine. To the dissolved polyvinyl butyral resins was added 15
mol equivalents of acetic anhydride, and the mixture was stirred at
80.degree. C. for 120 minutes. The pyridine was removed, and then
the polyvinyl butyral resin was washed with water and dried.
Thereby, a polyvinyl butyral resin h was obtained. With respect to
the obtained polyvinyl butyral resin h, the degree of acetylation
was 35 mol %, the degree of butyralization was 58 mol %, and the
hydroxy group content was 7 mol %. The proportion of the
high-molecular-weight component X (polyvinyl butyral resin) with an
absolute molecular weight of 1,000,000 or higher was 19.6% in the
obtained polyvinyl butyral resin. The proportion of the
high-molecular-weight component Y (polyvinyl butyral resin) with a
molecular weight y of 1,000,000 or higher was 23.1% in the obtained
polyvinyl butyral resin Z.
Synthesis Example 9
Synthesis of Polyvinyl Butyral Resin i
[0161] A polyvinyl butyral resin (average degree of polymerization:
3,050) having a degree of acetylation of 20 mol %, a degree of
butyralization of 26 mol %, and a hydroxy group content of 54 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 47 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin i was obtained. With
respect to the obtained polyvinyl butyral resin i, the degree of
acetylation was 67 mol %, the degree of butyralization was 26 mol
%, and the hydroxy group content was 7 mol %.
Synthesis Example 10
Synthesis of Polyvinyl Butyral Resin j
[0162] A polyvinyl butyral resin (average degree of polymerization:
3,050) having a degree of acetylation of 30 mol %, a degree of
butyralization of 13 mol %, and a hydroxy group content of 57 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 50 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin j was obtained. With
respect to the obtained polyvinyl butyral resin j, the degree of
acetylation was 80 mol %, the degree of butyralization was 13 mol
%, and the hydroxy group content was 7 mol %.
Synthesis Example 11
Synthesis of Polyvinyl Butyral Resin k
[0163] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 20 mol %, a degree of
butyralization of 58 mol %, and a hydroxy group content of 22 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 20 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin k was obtained. With
respect to the obtained polyvinyl butyral resin k, the degree of
acetylation was 40 mol %, the degree of butyralization was 58 mol
%, and the hydroxy group content was 2 mol %.
Synthesis Example 12
Synthesis of Polyvinyl Butyral Resin l
[0164] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 20 mol %, a degree of
butyralization of 52 mol %, and a hydroxy group content of 28 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 12 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin l was obtained. With
respect to the obtained polyvinyl butyral resin l, the degree of
acetylation was 32 mol %, the degree of butyralization was 52 mol
%, and the hydroxy group content was 16 mol %.
Synthesis Example 13
Synthesis of Polyvinyl Butyral Resin m
[0165] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 20 mol %, a degree of
butyralization of 50 mol %, and a hydroxy group content of 30 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 10.5 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin m was obtained. With
respect to the obtained polyvinyl butyral resin a, the degree of
acetylation was 30.5 mol %, the degree of butyralization was 50 mol
%, and the hydroxy group content was 19.5 mol %.
Synthesis Example 14
Synthesis of Polyvinyl Butyral Resin n
[0166] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 20 mol %, a degree of
butyralization of 55 mol %, and a hydroxy group content of 25 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 10.5 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin n was obtained. With
respect to the obtained polyvinyl butyral resin n, the degree of
acetylation was 30.5 mol %, the degree of butyralization was 55 mol
%, and the hydroxy group content was 14.5 mol %.
Synthesis Example 15
Synthesis of Polyvinyl Butyral Resin q
[0167] A polyvinyl butyral resin (average degree of polymerization:
3,000) having a degree of acetylation of 10 mol %, a degree of
butyralization of 65 mol %, and a hydroxy group content of 25 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 20.5 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin q was obtained. With
respect to the obtained polyvinyl butyral resin q, the degree of
acetylation was 30.5 mol %, the degree of butyralization was 65 mol
%, and the hydroxy group content was 4.5 mol %.
Synthesis Example 16
Synthesis of Polyvinyl Butyral Resin r
[0168] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 30 mol %, a degree of
butyralization of 45 mol %, and a hydroxy group content of 25 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 10 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin r was obtained. With
respect to the obtained polyvinyl butyral resin r, the degree of
acetylation was 40 mol %, the degree of butyralization was 45 mol
%, and the hydroxy group content was 15 mol %.
Synthesis Example 17
Synthesis of Polyvinyl Butyral Resin t
[0169] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 20 mol %, a degree of
butyralization of 50 mol %, and a hydroxy group content of 30 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 20 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin t was obtained. With
respect to the obtained polyvinyl butyral resin t, the degree of
acetylation was 40 mol %, the degree of butyralization was 50 mol
%, and the hydroxy group content was 10 mol %.
Synthesis Example 18
Synthesis of Polyvinyl Butyral Resin u
[0170] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 20 mol %, a degree of
butyralization of 45 mol %, and a hydroxy group content of 35 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 30.7 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin u was obtained. With
respect to the obtained polyvinyl butyral resin u, the degree of
acetylation was 50.7 mol %, the degree of butyralization was 45 mol
%, and the hydroxy group content was 4.3 mol %.
Synthesis Example 19
Synthesis of Polyvinyl Butyral Resin v
[0171] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 30 mol %, a degree of
butyralization of 33.5 mol %, and a hydroxy group content of 36.5
mol % was dissolved in pyridine. To the dissolved polyvinyl butyral
resin was added 20.2 mol equivalents of acetic anhydride, and the
mixture was stirred at 80.degree. C. for 120 minutes. The pyridine
was removed, and then the polyvinyl butyral resin was washed with
water and dried. Thereby, a polyvinyl butyral resin v was obtained.
With respect to the obtained polyvinyl butyral resin v, the degree
of acetylation was 50.2 mol %, the degree of butyralization was
33.5 mol %, and the hydroxy group content was 16.3 mol %.
Synthesis Example 20
Synthesis of Polyvinyl Butyral Resin w
[0172] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 30 mol %, a degree of
butyralization of 28.4 mol %, and a hydroxy group content of 41.6
mol % was dissolved in pyridine. To the dissolved polyvinyl butyral
resin was added 20.5 mol equivalents of acetic anhydride, and the
mixture was stirred at 80.degree. C. for 120 minutes. The pyridine
was removed, and then the polyvinyl butyral resin was washed with
water and dried. Thereby, a polyvinyl butyral resin w was obtained.
With respect to the obtained polyvinyl butyral resin w, the degree
of acetylation was 50.5 mol %, the degree of butyralization was
28.4 mol %, and the hydroxy group content was 21.1 mol %.
Synthesis Example 21
Synthesis of Polyvinyl Butyral Resin x
[0173] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 30 mol %, a degree of
butyralization of 35 mol %, and a hydroxy group content of 35 mol %
was dissolved in pyridine. To the dissolved polyvinyl butyral resin
was added 30 mol equivalents of acetic anhydride, and the mixture
was stirred at 80.degree. C. for 120 minutes. The pyridine was
removed, and then the polyvinyl butyral resin was washed with water
and dried. Thereby, a polyvinyl butyral resin x was obtained. With
respect to the obtained polyvinyl butyral resin x, the degree of
acetylation was 60 mol %, the degree of butyralization was 35 mol
%, and the hydroxy group content was 5 mol %.
Synthesis Example 22
Synthesis of Polyvinyl Butyral Resin y
[0174] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 30 mol %, a degree of
butyralization of 29.5 mol %, and a hydroxy group content of 40.5
mol % was dissolved in pyridine. To the dissolved polyvinyl butyral
resin was added 30 mol equivalents of acetic anhydride, and the
mixture was stirred at 80.degree. C. for 120 minutes. The pyridine
was removed, and then the polyvinyl butyral resin was washed with
water and dried. Thereby, a polyvinyl butyral resin y was obtained.
With respect to the obtained polyvinyl butyral resin y, the degree
of acetylation was 60 mol %, the degree of butyralization was 29.5
mol %, and the hydroxy group content was 10.5 mol %.
Synthesis Example 23
Synthesis of Polyvinyl Butyral Resin z
[0175] A polyvinyl butyral resin (average degree of polymerization:
3,200) having a degree of acetylation of 30 mol %, a degree of
butyralization of 24.3 mol %, and a hydroxy group content of 45.7
mol % was dissolved in pyridine. To the dissolved polyvinyl butyral
resin was added 30 mol equivalents of acetic anhydride, and the
mixture was stirred at 80.degree. C. for 120 minutes. The pyridine
was removed, and then the polyvinyl butyral resin was washed with
water and dried. Thereby, a polyvinyl butyral resin z was obtained.
With respect to the obtained polyvinyl butyral resin z, the degree
of acetylation was 60 mol %, the degree of butyralization was 24.3
mol %, and the hydroxy group content was 15.7 mol %.
Synthesis Example 24
Synthesis of Polyvinyl Butyral Resin o
[0176] To 3,000 g of pure water was added 190 g of polyvinyl
alcohol with a degree of saponification of 98.2% and a degree of
polymerization of 1,700, and then the mixture was heated so that
the polyvinyl alcohol was dissolved into the pure water. The
temperature of the solution was controlled to 12.degree. C. To the
solution were added 212 g of 35 wt % hydrochloric acid and 136 g of
n-butyl aldehyde, and a polyvinyl butyral resin was precipitated.
Thereafter, the reaction system was kept at 50.degree. C. for 4
hours, and the reaction was finished. The resin was washed with
excess water so that unreacted n-butyl aldehyde was washed away.
Further, the hydrochloric acid catalyst was neutralized and the
salt was removed, and then the product was dried. Thereby, a
polyvinyl butyral resin o was obtained. With respect to the
obtained polyvinyl butyral resin o, the degree of acetylation was
1.8 mol %, the degree of butyralization was 68.5 mol %, and the
hydroxy group content was 29.7 mol %.
Synthesis Example 25
Synthesis of Polyvinyl Butyral Resin p
[0177] To 3,000 g of pure water was added 190 g of polyvinyl
alcohol with a degree of saponification of 98.8% and a degree of
polymerization of 1,700, and then the mixture was heated so that
the polyvinyl alcohol was dissolved into the pure water. The
temperature of the solution was controlled to 12.degree. C. To the
solution were added 206 g of 35 wt % hydrochloric acid and 142 g of
n-butyl aldehyde, and a polyvinyl butyral resin was precipitated.
Thereafter, the reaction system was kept at 50.degree. C. for 4
hours, and the reaction was finished. The resin was washed with
excess water so that unreacted n-butyl aldehyde was washed away.
Further, the hydrochloric acid catalyst was neutralized and the
salt was removed, and then the product was dried. Thereby, a
polyvinyl butyral resin p was obtained. With respect to the
obtained polyvinyl butyral resin p, the degree of acetylation was
1.2 mol %, the degree of butyralization was 72.4 mol %, and the
hydroxy group content was 26.4 mol %.
Synthesis Example 26
Synthesis of Polyvinyl Butyral Resin s
[0178] To 2,910 g of pure water was added 190 g of polyvinyl
alcohol with a degree of polymerization of 1,700, and then the
mixture was heated so that the polyvinyl alcohol was dissolved into
the pure water. The temperature of the solution was controlled to
12.degree. C. To the solution were added 201 g of 35 wt %
hydrochloric acid and 122 g of n-butyl aldehyde, and a polyvinyl
butyral resin was precipitated. Thereafter, the reaction system was
kept at 50.degree. C. for 4 hours, and the reaction was finished.
The resin was washed with excess water so that unreacted n-butyl
aldehyde was washed away. Further, the hydrochloric acid catalyst
was neutralized and the salt was removed, and then the product was
dried. Thereby, a polyvinyl butyral resin s was obtained. With
respect to the obtained polyvinyl butyral resin s, the degree of
acetylation was 1 mol %, the degree of butyralization was 62.5 mol
%, and the hydroxy group content was 36.5 mol %.
Synthesis Example 27
Synthesis of Polyvinyl Butyral Resin AA
[0179] To 3,000 g of pure water was added 190 g of polyvinyl
alcohol with a degree of saponification of 99.0% and a degree of
polymerization of 1,700, and then the mixture was heated so that
the polyvinyl alcohol was dissolved into the pure water. The
temperature of the solution was controlled to 12.degree. C. To the
solution were added 212 g of 35 wt % hydrochloric acid and 124 g of
n-butyl aldehyde, and a polyvinyl butyral resin was precipitated.
Thereafter, the reaction system was kept at 50.degree. C. for 4
hours, and the reaction was finished. The resin was washed with
excess water so that unreacted n-butyl aldehyde was washed away.
Further, the hydrochloric acid catalyst was neutralized and the
salt was removed, and then the product was dried. Thereby, a
polyvinyl butyral resin AA was obtained. With respect to the
obtained polyvinyl butyral resin AA, the degree of acetylation was
1.0 mol %, the degree of butyralization was 62.5 mol %, and the
hydroxy group content was 36.5 mol %.
Synthesis Example 28
Synthesis of Polyvinyl Butyral Resin AB
[0180] A resin AB was obtained by butyralization of polyvinyl
alcohol with a degree of saponification of 87.2% and a degree of
polymerization of 2,300 by a common method. With respect to the
obtained polyvinyl butyral resin AB, the degree of acetylation was
12.8 mol %, the degree of butyralization was 63.5 mol %, and the
hydroxy group content was 23.7 mol %.
Synthesis Example 29
Synthesis of Polyvinyl Butyral Resin AC
[0181] A resin AC was obtained by butyralization of polyvinyl
alcohol with a degree of saponification of 70.5% and a degree of
polymerization of 2,300 by a common method. With respect to the
obtained polyvinyl butyral resin AC, the degree of acetylation was
29.5 mol %, the degree of butyralization was 34 mol %, and the
hydroxy group content was 36.5 mol %.
Synthesis Example 30
Synthesis of Polyvinyl Butyral Resin AD
[0182] A resin AD was obtained by butyralization of polyvinyl
alcohol with a degree of saponification of 70.5% and a degree of
polymerization of 2,300 by a common method. With respect to the
obtained polyvinyl butyral resin AD, the degree of acetylation was
29.5 mol %, the degree of butyralization was 30.0 mol %, and the
hydroxy group content was 40.5 mol %.
Example 1
[0183] (1) Preparation of Intermediate Film
[0184] The obtained polyvinyl butyral resin a (degree of
acetylation: 30.5 mol %, 100 parts by weight) and triethylene
glycol di-2-ethyl hexanoate (50 parts by weight) as a plasticizer
were sufficiently kneaded using a mixing roll, and thereby a
composition for intermediate layer was obtained.
[0185] The polyvinyl butyral resin d (degree of acetylation: 1 mol
%, 100 parts by weight) and triethylene glycol di-2-ethyl hexanoate
(3GO, 20 parts by weight) as a plasticizer were sufficiently
kneaded, and thereby a composition for protecting layer was
obtained.
[0186] The obtained composition for intermediate layer and
composition for protecting layer were molded using a co-extruder,
and thereby a multilayer intermediate film (thickness: 0.8 mm)
having a laminated structure of protecting layer B (thickness: 0.35
mm)/intermediate layer A (thickness: 0.1 mm)/protecting layer B
(thickness: 0.35 mm) was prepared.
[0187] (2) Preparation of Laminated Glass Used for Measurement of
Loss Factor
[0188] The obtained multilayer intermediate film was cut into a
size of 30 mm in length.times.320 mm in width. Next, the multilayer
intermediate film was sandwiched between two transparent float
glasses (25 mm in length.times.305 mm in width.times.2.0 mm in
thickness). The workpiece was maintained and vacuum-pressed at
90.degree. C. for 30 minutes using a vacuum laminator, and thereby
a laminate was obtained. Portions of the multilayer intermediate
film bulged out of the glasses in the laminate were cut away, and
thereby a laminated glass to be used for measurement of loss factor
was obtained.
[0189] (3) Preparation of Laminated Glass Used in Bubble Formation
Test A and Bubble Formation Test B
[0190] The obtained multilayer intermediate film was cut into a
size of 30 cm in length.times.15 cm in width, and then stored for
10 hours under the 23.degree. C. condition. Embossment was formed
on both surfaces of the obtained multilayer intermediate film, and
the 10-point average roughness of the embossment was 30 .mu.m. On
the cut multilayer intermediate film, 6-mm-diameter through holes
were formed at four respective points, each point being an
intersection of a position that is 8 cm inside from one edge of the
multilayer intermediate film in the length direction and a position
that is 5 cm inside from one edge of the multilayer intermediate
film in the width direction.
[0191] The multilayer intermediate film with the through holes was
sandwiched between two transparent float glasses (30 cm in
length.times.15 cm in width.times.2.5 mm in thickness), and thereby
a laminate was obtained. The peripheral edge of the laminate was
heat-sealed by 2 ac in width from the edge, and thereby the air
remained in the embossment and the air remained in the through
holes were sealed. This laminate was press-bonded at 135.degree. C.
and 1.2 MPa for 20 minutes, and thereby the residual air was
dissolved into the multilayer intermediate film. As a result, a
laminated glass to be used in the Bubble formation test A and the
Bubble formation test B was obtained. The laminated glass to be
used in the Bubble formation test A and the Bubble formation test B
was prepared using one of the multilayer intermediate films of
Examples 6 to 41 and Comparative Examples 2 to 4.
Examples 2 to 41 and Comparative Examples 1 to 4
[0192] Except that the types and amounts of the polyvinyl butyral
resin and the types and amounts of the plasticizer used in the
intermediate layer A and the protecting layers B were those shown
in Tables 1 to 5, a multilayer intermediate film and a laminated
glass were obtained in the same manner as in Example 1. Further, in
Examples 12, 19, and 27, the thickness of the intermediate layer A
was 0.13 mm and the thickness of each protecting layer B was 0.375
mm. In Examples 13, 20, and 28, the thickness of the intermediate
layer A was 0.08 mm and the thickness of each protecting layer B
was 0.36 mm.
[0193] (Evaluation)
[0194] (1) Peak Temperature of Tan .delta. at Low-Temperature Side,
Peak Maximum Value of Tan .delta. at Low-Temperature Side, and Peak
Maximum Value of Tan .delta. at High-Temperature Side
[0195] The obtained intermediate film was stored in a 20.degree. C.
environment for one month, and then the intermediate film was cut
out into a 8-mm-diameter circular shape. The temperature variance
of the dynamic viscoelasticity was measured by a shear method using
a rheometer ("ARES", Rheometric Scientific, Inc.) under the
following conditions: a strain of 1.0%, a frequency of 1 Hz, and a
temperature-increasing rate of 5.degree. C./min. Thereby, the peak
temperature of tan .delta. at low-temperature side, the peak
maximum value of tan .delta. at low-temperature side, and the peak
maximum value of tan .delta. at high-temperature side were
measured.
[0196] (2) Loss Factor
[0197] A Laminated glass to be used for the measurement of loss
factor was stored in a 20.degree. C. environment for one month. The
loss factor of the laminated glass stored in the 20.degree. C.
environment for one month was measured by a center exciting method
at 20.degree. C. using a measurement device "SA-01" (RION Co.,
Ltd.). The loss factor (loss factor at 20.degree. C.) in the 4th
mode of resonant frequency (around 3,150 Hz) of the loss factor
obtained was evaluated.
[0198] Further, the loss factor of the laminated glass stored in
the 20.degree. C. environment for one month was measured by a
center exciting method at 30.degree. C. using a measurement device
"SA-01" (RION Co., Ltd.). The loss factor (loss factor at
30.degree. C.) in the 6th mode of resonant frequency (around 6,300
Hz) of the loss factor obtained was evaluated.
[0199] (3) Bubble Formation Test A (State of Bubble Formation)
[0200] With respect to each of the multilayer intermediate films in
Examples 6 to 41 and Comparative Examples 2 to 4, five laminated
glasses to be used in the bubble formation test A were produced,
and then left to stand for 100 hours in a 50.degree. C. oven. The
left laminated glasses were visually observed for the presence of
bubble formation and the size of the bubbles in a plan view, and
the state of bubble formation was evaluated based on the following
criteria.
[0201] [Criteria for the State of Bubble Formation in the Bubble
Formation Test A]
[0202] The bubbles generated in the five laminated glasses each
were approximated to an ellipse, and the area of the ellipse was
defined as the area of the bubble. The areas of the ellipses
observed in the five laminated glass were averaged, and the
proportion (percentage) of the averaged value (bubble formation
area) of the areas of the ellipses to the area (30 cm.times.15 cm)
of the laminated glass was determined.
[0203] oo: No bubble formation was observed in any of five
laminated glasses
[0204] o: The ratio of the average value (bubble formation area) of
the areas of bubble formation was lower than 5%
[0205] .DELTA.: The ratio of the average value (bubble formation
area) of the areas of bubble formation was 5% or higher and lower
than 10%
[0206] x: The ratio of the average value (bubble formation area) of
the areas of bubble formation was 10% or higher
[0207] (4) Bubble Formation Test B (State of Bubble Formation)
[0208] With respect to each of the multilayer intermediate films in
Examples 6 to 41 and Comparative Examples 2 to 4, laminated glasses
to be used in the bubble formation test B were produced, and then
left to stand for 24 hours in a 50.degree. C. oven. The number of
laminated glasses in which bubble formation was visually observed
among the left laminated glasses was counted, and the state of
bubble formation was evaluated based on the following criteria.
[0209] [Criteria for the State of Bubble Formation in the Bubble
Formation Test B]
[0210] oo: The number of laminated glasses in which bubble
formation was visually observed was 5 or less
[0211] o: The number of laminated glasses in which bubble formation
was visually observed was 6 or more and 10 or less
[0212] .DELTA.: The number of laminated glasses in which bubble
formation was visually observed was 11 or more and 15 or less
[0213] x: The number of laminated glasses in which bubble formation
was visually observed was 16 or more
[0214] (5) Measurement of Elastic Modulus G' by Test Method A
[0215] The polyvinyl acetal resin to be contained in the
intermediate layer (first layer) of the intermediate film for
laminated glass of each of Examples 6 to 41 and Comparative
Examples 2 to 4 (the polyvinyl acetal resin used for intermediate
layer) (100 parts by weight) and triethylene glycol di-2-ethyl
hexanoate (3GO) (60 parts by weight) as a plasticizer were
sufficiently kneaded, and thereby a kneaded product was obtained.
The obtained kneaded product was press-molded using a press-molding
machine, and thereby a resin film A with an average thickness of
0.35 mm was obtained. The obtained resin film A was left for two
hours at a temperature of 25.degree. C. and a relative humidity of
30%. After two hours, the viscoelasticity was measured using
ARES-G2 (TA INSTRUMENTS). The geometry used here was a
8-mm-diameter parallel plate. The measurement was performed under
the condition wherein the temperature was lowered from 100.degree.
C. to -10.degree. C. at a lowering rate of 3.degree. C./min and
under the condition with a frequency of 1 Hz and a strain of 1%. In
the obtained measurement results, the peak temperature of the loss
factor was defined as a glass transition temperature Tg (.degree.
C.). Further, Based on the obtained measurement results and the
glass transition temperature Tg, the value of the elastic modulus
G'(Tg+30) at (Tg+30.degree.).degree. C. and the value of the
elastic modulus G'(Tg+80) at (Tg+80.degree.).degree. C. were read,
and the ratio (G'(Tg+80)/G'(Tg+30)) was determined.
[0216] (6) Measurement of Elastic Modulus G' by Test Method B
[0217] The intermediate film for laminated glass of each of
Examples 6 to 41 and Comparative Examples 2 to 4 was stored in a
constant temperature and humidity facility (humidity: 30%(.+-.3%),
temperature: 23.degree. C.) for one month. Immediately after the
storage for one month, the surface layer, the intermediate layer,
and the surface layer were separated, and thereby the intermediate
layer was taken out. One gram of the separated intermediate layer
was placed in a mold (2 cm in length.times.2 cm in width.times.0.76
mm in thickness) disposed between two polyethylene terephthalate
(PET) films. The intermediate layer was preheated at a temperature
of 150.degree. C. and a pressure of 0 kg/cm.sup.2 for 10 minutes,
and then press-molded at 80 kg/cm.sup.2 for 15 minutes. The
press-molded intermediate layer was placed in a hand press set to
20.degree. C. in advance, and then pressed at 10 MPa for 10
minutes. Thereby, the intermediate layer was cooled down. Next, one
of the two PET films was peeled off from the mold disposed
therebetween, and it was stored in a constant temperature and
humidity facility (humidity: 30% (.+-.3%), temperature: 23.degree.
C.) for 24 hours. Then, the viscoelasticity was measured using
ARES-G2 (TA INSTRUMENTS). The geometry used here was a
8-mm-diameter parallel plate. The measurement was performed under
the condition wherein the temperature was lowered from 100.degree.
C. to -10.degree. C. at a lowering rate of 3.degree. C./min and
under the condition with a frequency of 1 Hz and a strain of 1%. In
the obtained measurement results, the peak temperature of the loss
factor was defined as a glass transition temperature Tg(.degree.
C.). Further, based on the obtained measurement results and the
glass transition temperature Tg, the value of the elastic modulus
G'(Tg+30) at (Tg+30.degree.).degree. C. and the value of the
elastic modulus G'(Tg+80) at (Tg+80.degree.).degree. C. were read.
In addition, the ratio (G'(Tg+80)/G'(Tg+30)) was determined.
[0218] (7) Measurement of Absolute Molecular Weight and Molecular
Weight y
[0219] (Measurement of Absolute Molecular Weight)
[0220] The absolute molecular weight and the molecular weight in
terms of polystyrene for determining the ratio of the
high-molecular-weight component X and the high-molecular-weight
component Y mentioned in Synthesis Example 8 were values determined
by separating the surface layers and the intermediate layer of the
obtained multilayer intermediate film, and then performing the
following steps.
[0221] In order to measure the absolute molecular weight, the
multilayer intermediate film was left in a constant temperature and
humidity facility (humidity: 30% (.+-.3%), temperature: 23.degree.
C.) for one month. After one month, the surface layers and the
intermediate layer of the intermediate film were separated. The
separated intermediate layer was dissolved in tetrahydrofuran (THF)
to prepare a 0.1 wt % solution. The obtained solution was analyzed
using a Gel Permeation Chromatography (GPC) device (Hitachi
High-Technologies Corp., RI: L2490, auto-sampler: L-2200, pump:
L-2130, column oven: L-2350, columns: GL-A120-S and GL-A100MX-S in
series). This GPC device was connected with a light scattering
detector for GPC (VISCOTEK, Model 270 (RALS+VISCO)), and thus the
chromatograms of the respective detectors can be analyzed. The
peaks of the polyvinyl acetal resin component in the chromatograms
of the RI detector and RALS detector were analyzed using an
analysis software (OmniSEC), and thereby the absolute molecular
weight at each elution time of the polyvinyl acetal resin was
determined. The ratio of the area of a region where the absolute
molecular weight of the polyvinyl acetal resin is 1,000,000 or
higher in the peak area of the polyvinyl acetal resin detected by
the RI detector was represented in percentage (%).
[0222] The following formulas hold for the peaks of the respective
components in the chromatograms.
A.sub.RI=c.times.(dn/dc).times.K.sub.RI (1)
A.sub.RALS=c.times.M.times.(dn/dc).sup.2.times.K.sub.RALS (2)
[0223] In the formulas, c represents the polymer concentration in
solution, (dn/dc) represents the increment of refractive index, M
represents the absolute molecular weight, and K represents the
system's coefficient.
[0224] In the specific measurement procedure, first, 0.1 wt % THF
solution was prepared using a polystyrene standard sample (VISCOTEK
Corp., PolyCAL (registered trademark) TDS-PS-NB, Mw=98,390,
dn/dc=0.185) with known c, M, and (dn/dc) values. Based on the GPC
measurement result of the obtained polystyrene solution, the
system's coefficient K of each detector was determined using the
formula (1) and the formula (2).
[0225] Next, the separated intermediate layer was dissolved in THF,
and thereby a THF solution was prepared. Based on the GPC
measurement result of the obtained polyvinyl acetal resin solution,
the absolute molecular weight M of the polyvinyl acetal resin was
determined using the formula (1) and the formula (2).
[0226] Here, in order to analyze the intermediate layer (containing
polyvinyl acetal resin and plasticizer), the concentration of the
polyvinyl acetal resin in the polyvinyl acetal resin solution needs
to be determined. The concentration of the polyvinyl acetal resin
was calculated from result of the following measurement of amount
of plasticizer.
[0227] Measurement of Amount of Plasticizer:
[0228] The plasticizer was dissolved in THF such that the amount of
the plasticizer was to be 10% by weight, 15% by weight, 20% by
weight, 25% by weight, 30% by weight, 35% by weight, 40% by weight,
45% by weight, or 50% by weight, and thereby a plasticizer-THF
solution was prepared. The obtained plasticizer-THF solution was
subjected to GPC measurement, and the peak area of the plasticizer
was determined. The peak areas of the plasticizer were plotted with
respect to each concentration of the plasticizer, and thereby an
approximate straight line was obtained. Next, the THF solution
containing the intermediate layer dissolved in THF was subjected to
GPC measurement, and the amount of the plasticizer was determined
from the peak area of the plasticizer using the approximate
straight line.
[0229] (Measurement of Molecular Weight y)
[0230] In the same manner as in the aforementioned measurement
method of the absolute molecular weight, the molecular weight in
terms of polystyrene was measured by gel permeation chromatography
(GPC). The proportion (%) of the high-molecular-weight component Y
with a molecular weight y of 1,000,000 or higher in the polyvinyl
acetal resin was calculated from the ratio of the area
corresponding to a region where the molecular weight was 1,000,000
or higher among the peak areas detected by the RI detector
(measurement results of GPC).
[0231] In order to measure the molecular weight in terms of
polystyrene, the polystyrene standard samples with known molecular
weights were subjected to GPC measurement. As the polystyrene
standard samples ("Shodex Standard SM-105", "Shodex Standard
SH-75", SHOWA DENKO K.K.) were used 14 samples with the respective
weight average molecular weights of 580, 1,260, 2,960, 5,000,
10,100, 21,000, 28,500, 76,600, 196,000, 630,000, 1,130,000,
2,190,000, 3,150,000, and 3,900,000. Weight average molecular
weights were plotted with respect to the corresponding elution
times indicated by the peak tops of the peaks of the respective
standard samples, and the obtained approximate straight line was
used as a calibration curve. A multilayer intermediate film was
left in a constant temperature and humidity facility (humidity: 30%
(.+-.3%), temperature: 23.degree. C.) for one month, and then the
surface layers and the intermediate layer were separated. The
separated intermediate layer was dissolved in tetrahydrofuran (THF)
to prepare a 0.1 wt % solution. The obtained solution was analyzed
using a GPC device, and the peak area of the polyvinyl acetal resin
in the intermediate layer was measured. Next, the area
corresponding to the region where the molecular weight in terms of
polystyrene of the polyvinyl acetal resin in the intermediate layer
was 1,000,000 or higher was calculated from the elution time and
the calibration curve of the polyvinyl acetal resin in the
intermediate layer. The proportion (%) of the high-molecular-weight
component Y with a molecular weight y of 1,000,000 or higher in the
polyvinyl acetal resin was calculated by representing in percentage
(%) the value obtained by dividing the area corresponding to the
region where the molecular weight in terms of polystyrene of the
polyvinyl acetal resin in the intermediate layer was 1,000,000 or
higher by the peak area of the polyvinyl acetal resin in the
intermediate layer.
[0232] The results are shown in the following Tables 1 to 5. In the
following Tables 1 to 5, "3GO" represents triethylene glycol
di-2-ethyl hexanoate, "DBA" represents dibutyl adipate, and "3 GB"
represents triethylene glycol dibutyrate.
TABLE-US-00001 TABLE 1 Example Example Example Example Example
Comparative 1 2 3 4 5 Example 1 Intermediate Resin Type a b c f g e
layer A Degree of butyralization (mol %) 40 35 25 59 45 63.5 Degree
of acetylation (mol %) 30.5 40 50 35 40 12.8 Amount (parts by
weight) 100 100 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO
3GO 3GO Amount (parts by weight) 50 45 40 40 40 60 Protecting Resin
Type d d d d d d layer B Degree of butyralization (mol %) 68.5 68.5
68.5 68.5 68.5 68.5 Degree of acetylation (mol %) 1 1 1 1 1 1
Amount (parts by weight) 100 100 100 100 100 100 Plasticizer Type
3GO 3GO 3GO 3GO 3GO 3GO Amount (parts by weight) 20 20 20 38.5 38.5
38.5 Layer structure B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B Peak
temperature of tan .delta. at low-temperature side -2.4 -3.2 -4
-2.8 -3.6 -1.8 Peak maximum value of tan .delta. at low-temperature
side 1.38 1.48 1.51 1.58 1.84 1.05 Peak maximum value of tan
.delta. at high-temperature side 0.56 0.59 0.55 0.52 0.51 0.54 Loss
factor at 20.degree. C. around 3.150 Hz 0.31 0.33 0.36 0.49 0.5
0.28 Loss factor at 30.degree. C. around 6.300 Hz 0.12 0.14 0.16
0.17 0.18 0.09
TABLE-US-00002 TABLE 2 Example Example Example Example Example
Example 6 7 8 9 10 11 Intermediate Resin Type h i j k l m layer A
Degree of butyralization 58 26 13 58 52 50 (mol %) Degree of
acetylation 35 67 80 40 32 30.5 (mol %) Amount (parts by weight)
100 100 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO 3GO
Amount (parts by weight) 50 50 50 50 50 50 Protecting Resin Type d
d d d d d layer B Degree of butyralization 68.5 68.5 68.5 68.5 68.5
68.5 (mol %) Degree of acetylation 1 1 1 1 1 1 (mol %) Amount
(parts by weight) 100 100 100 100 100 100 Plasticizer Type 3GO 3GO
3GO 3GO 3GO 3GO Amount (parts by weight)) 28 30 34 27 30 33 Layer
structure B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B Peak temperature of
tan .delta. at low-temperature side (.degree. C.) -1.7 -2.2 -2.7
-3.1 -2.9 -3.52 Peak maximum value of tan .delta. at
low-temperature side 1.66 1.84 1.59 1.74 1.68 1.57 Peak maximum
value of tan .delta. at high-temperature side 0.55 0.56 0.55 0.56
0.68 0.55 Loss factor at 20.degree. C. around 3.150 Hz 0.53 0.62
0.51 0.56 0.49 0.49 Loss factor at 30.degree. C. around 6.300 Hz
0.18 0.17 0.17 0.2 0.15 0.16 Bubble formation test A (state of
Bubble formation) .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. Bubble formation test B (state of Bubble
formation) .smallcircle. .smallcircle. .smallcircle. .smallcircle.
.smallcircle. .smallcircle. Test method A: glass transition
temperature (Tg) (.degree. C.) -2.51 -2.9 -3.2 -3.7 -3.5 -2.88 Test
method A: G' (Tg + 30) (Pa) 231500 223000 219000 212000 214500
234000 Test method A: G' (Tg + 80) (Pa) 158000 154800 149800 143000
145000 159000 Test method A: G' (Tg + 80)/G' (Tg + 30) 0.68 0.69
0.68 0.67 0.66 0.68 Test method B: glass transition temperature
(Tg) (.degree. C.) -4.72 -4.22 -6.2 -5.8 -6.41 -4.12 Test method B:
G' (Tg + 30) (Pa) 221500 216900 198500 201500 204300 225600 Test
method B: G' (Tg + 80) (Pa) 150400 148300 132700 132500 135400
152700 Test method B: G' (Tg + 80)/G' (Tg + 30) 0.68 0.88 0.67 0.88
0.68 0.68 Proportion of high-molecule-weight component X (%) 19.5
-- -- -- -- -- Proportion of high-molecule-weight component Y (%)
23.1 -- -- -- -- -- Example Example Example Example Example 12 13
14 15 16 Intermediate Resin Type n n n n n layer A Degree of
butyralization 55 55 55 55 55 (mol %) Degree of acetylation 30.5
30.5 30.5 30.5 30.5 (mol %) Amount (parts by weight) 100 100 100
100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO Amount (parts by
weight) 50 50 50 50 50 Protecting Resin Type d d o p d layer B
Degree of butyralization 68.5 68.5 68.5 72.4 68.5 (mol %) Degree of
acetylation 1 1 1.8 1.2 1 (mol %) Amount (parts by weight) 100 100
100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO Amount (parts by
weight)) 31 31 35 36 32.5 Layer structure B/A/B B/A/B B/A/B B/A/B
B/A/B Peak temperature of tan .delta. at low-temperature side
(.degree. C.) -4.12 -4.21 -4.68 -5.12 -4.65 Peak maximum value of
tan .delta. at low-temperature side 1.74 1.62 1.64 1.62 1.67 Peak
maximum value of tan .delta. at high-temperature side 0.51 0.53
0.56 0.58 0.54 Loss factor at 20.degree. C. around 3.150 Hz 0.55
0.5 0.51 0.5 0.52 Loss factor at 30.degree. C. around 6.300 Hz 0.19
0.17 0.17 0.16 0.17 Bubble formation test A (state of Bubble
formation) .smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. Bubble formation test B (state of Bubble
formation) .smallcircle. .smallcircle. .smallcircle. .smallcircle.
.smallcircle. Test method A: glass transition temperature (Tg)
(.degree. C.) -4.67 -4.67 -4.67 -4.67 -4.67 Test method A: G' (Tg +
30) (Pa) 228500 228500 228500 228500 228500 Test method A: G' (Tg +
80) (Pa) 157900 157900 157900 157900 157900 Test method A: G' (Tg +
80)/G' (Tg + 30) 0.69 0.69 0.69 0.69 0.69 Test method B: glass
transition temperature (Tg) (.degree. C.) -4.53 -4.6 -5.12 -5.33
-5.02 Test method B: G' (Tg + 30) (Pa) 227500 227000 221300 220700
224300 Test method B: G' (Tg + 80) (Pa) 154300 156000 152800 150800
154200 Test method B: G' (Tg + 80)/G' (Tg + 30) 0.68 0.69 0.69 0.68
0.69 Proportion of high-molecule-weight component X (%) -- -- -- --
-- Proportion of high-molecule-weight component Y (%) -- -- -- --
--
TABLE-US-00003 TABLE 3 Example Example Example Example Example
Example 17 18 19 20 21 22 Intermediate Resin Type q r r r r r layer
A Degree of butyralization 65 45 45 45 45 45 (mol %) Degree of
acetylation 30.5 40 40 40 40 40 (mol %) Amount (parts by weight)
100 100 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO 3GO
Amount (parts by weight) 50 50 50 50 50 50 Protecting Resin Type d
d d d o p layer B Degree of butyralization 68.5 68.5 68.5 68.5 68.5
72.4 (mol %) Degree of acetylation 1 1 1 1 1.8 1.2 (mol %) Amount
(parts by weight) 100 100 100 100 100 100 Plasticizer Type 3GO 3GO
3GO 3GO 3GO 3GO Amount (parts by weight) 34 28 28 28 32 34 Layer
structure B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B Peak temperature of
tan .delta. at low-temperature side (.degree. C.) -3.77 -4.12 -4.65
-5.01 -4.22 -4.56 Peak maximum value of tan .delta. at
low-temperature side 1.75 1.69 1.76 1.63 1.67 1.65 Peak maximum
value of tan .delta. at high-temperature side 0.54 0.63 0.5 0.51
0.54 0.55 Loss factor at 20.degree. C. around 3.150 Hz 0.56 0.52
0.55 0.5 0.51 0.51 Loss factor at 30.degree. C. around 6.300 Hz 0.2
0.17 0.2 0.16 0.16 0.16 Bubble formation test A (state of Bubble
formation) .smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle. Bubble
formation test B (state of Bubble formation) .smallcircle.
.smallcircle. .smallcircle. .smallcircle. .smallcircle.
.smallcircle. Test method A: glass transition temperature (Tg)
(.degree. C.) -6.43 -8.21 -8.21 -8.21 -8.21 -8.21 Test method A: G'
(Tg + 30) (Pa) 202700 210600 210600 210600 210600 2106000 Test
method A: G' (Tg + 80) (Pa) 136000 145700 145700 145700 145700
145700 Test method A: G' (Tg + 80)/G' (Tg + 30) 0.67 0.69 0.69 0.69
0.69 0.69 Test method B: glass transition temperature (Tg)
(.degree. C.) -4.11 -4.56 -4.83 -5.33 -4.56 -5.02 Test method B: G'
(Tg + 30) (Pa) 219600 224600 22600 221500 225300 224600 Test method
B: G' (Tg + 80) (Pa) 145800 152400 153200 153700 153000 153200 Test
method B: G' (Tg + 80)/G' (Tg + 30) 0.68 0.68 0.68 0.69 0.68 0.68
Proportion of high-molecule-weight component X (%) -- -- -- -- --
-- Proportion of high-molecule-weight component Y (%) -- -- -- --
-- -- Example Example Example Example Example 23 24 25 26 27
Intermediate Resin Type r t u v v layer A Degree of butyralization
45 50 45 33.5 33.5 (mol %) Degree of acetylation 40 40 50.7 50.2
50.2 (mol %) Amount (parts by weight) 100 100 100 100 100
Plasticizer Type 3GO 3GO 3GO 3GO 3GO Amount (parts by weight) 50 50
50 50 50 Protecting Resin Type e d d d d layer B Degree of
butyralization 82.5 68.5 68.5 68.5 68.5 (mol %) Degree of
acetylation 1 1 1 1 1 (mol %) Amount (parts by weight) 100 100 100
100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO Amount (parts by
weight) 24 30 34 31 31 Layer structure B/A/B B/A/B B/A/B B/A/B
B/A/B Peak temperature of tan .delta. at low-temperature side
(.degree. C.) -4.33 -3.54 -4.77 -4.21 -4.51 Peak maximum value of
tan .delta. at low-temperature side 1.74 1.74 1.78 1.72 1.78 Peak
maximum value of tan .delta. at high-temperature side 0.55 0.56
0.52 0.54 0.57 Loss factor at 20.degree. C. around 3.150 Hz 0.55
0.56 0.57 0.55 0.56 Loss factor at 30.degree. C. around 6.300 Hz
0.19 0.2 0.21 0.19 0.2 Bubble formation test A (state of Bubble
formation) .smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. Bubble formation test B (state of Bubble
formation) .smallcircle. .smallcircle. .smallcircle. .smallcircle.
.smallcircle. Test method A: glass transition temperature (Tg)
(.degree. C.) -12.14 -5.77 -3.12 -5.68 -5.68 Test method A: G' (Tg
+ 30) (Pa) 200400 205300 228200 224500 224500 Test method A: G' (Tg
+ 80) (Pa) 134500 136900 152900 153900 153900 Test method A: G' (Tg
+ 80)/G' (Tg + 30) 0.67 0.67 0.67 0.69 0.69 Test method B: glass
transition temperature (Tg) (.degree. C.) -4.83 -4.1 -5.04 -4.51
-4.86 Test method B: G' (Tg + 30) (Pa) 225600 220100 206400 227400
226000 Test method B: G' (Tg + 80) (Pa) 149700 148000 135900 156100
155800 Test method B: G' (Tg + 80)/G' (Tg + 30) 0.66 0.67 0.68 0.69
0.69 Proportion of high-molecule-weight component X (%) -- -- -- --
-- Proportion of high-molecule-weight component Y (%) -- -- -- --
--
TABLE-US-00004 TABLE 4 Example Example Example Example Example
Example 28 29 30 31 32 33 Intermediate Resin Type v v v w x y layer
A Degree of butyralization 33.5 33.5 33.5 28.4 35 29.5 (mol %)
Degree of acetylation 50.2 50.2 50.2 50.5 60 60 (mol %) Amount
(parts by weight) 100 100 100 100 100 100 Plasticizer Type 3GO 3GO
3GO 3GO 3GO 3GO Amount (parts by weight) 50 50 50 50 50 50
Protecting Resin Type d o p d d d layer B Degree of butyralization
68.5 68.5 72.4 68.5 68.5 68.5 (mol %) Degree of acetylation 1 1.8
1.2 1 1 1 (mol %) Amount (parts by weight) 100 100 100 100 100 100
Plasticizer Type 3GO 3GO 3GO 3GO 3GO 3GO Amount (parts by weight)
31 34 36 33 35 33 Layer structure B/A/B B/A/B B/A/B B/A/B B/A/B
B/A/B Peak temperature of tan .delta. at low-temperature side
(.degree. C.) -4.77 -4.66 -5.24 -4.56 -3.88 -4.01 Peak maximum
value of tan .delta. at low-temperature side 1.66 1.7 1.68 1.81
1.74 1.73 Peak maximum value of tan .delta. at high-temperature
side 0.54 0.56 0.58 0.55 0.54 0.55 Loss factor at 20.degree. C.
around 3.150 Hz 0.61 0.52 0.52 0.5 0.55 0.54 Loss factor at
30.degree. C. around 6.300 Hz 0.18 0.18 0.18 0.17 0.2 0.2 Bubble
formation test A (state of Bubble formation)
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle. Bubble
formation test B (state of Bubble formation) .smallcircle.
.smallcircle. .smallcircle. .smallcircle. .smallcircle.
.smallcircle. Test method A: glass transition temperature (Tg)
(.degree. C.) -5.68 -5.68 -5.68 -3.84 -2.52 -3.85 Test method A: G'
(Tg + 30) (Pa) 224500 224500 224500 228400 231800 229800 Test
method A: G' (Tg + 80) (Pa) 153900 153900 153900 181000 154800
158000 Test method A: G' (Tg + 80)/G' (Tg + 30) 0.69 0.69 0.69 0.70
0.67 0.66 Test method B: glass transition temperature (Tg)
(.degree. C.) -5.22 -5.05 -5.64 -5.37 -4.11 -4.5 Test method B: G'
(Tg + 30) (Pa) 224700 218000 209300 210400 213000 220500 Test
method B: G' (Tg + 80) (Pa) 156000 150800 143600 147600 140700
146800 Test method B: G' (Tg + 80)/G' (Tg + 30) 0.69 0.69 0.69 0.70
0.68 0.67 Proportion of high-molecule-weight component X (%) -- --
-- -- -- -- Proportion of high-molecule-weight component Y (%) --
-- -- -- -- -- Example Example Example Example Example 34 35 36 37
38 Intermediate Resin Type y y y y z layer A Degree of
butyralization 29.5 29.5 29.5 29.5 24.3 (mol %) Degree of
acetylation 60 60 60 60 60 (mol %) Amount (parts by weight) 100 100
100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO Amount (parts by
weight) 50 50 50 50 50 Protecting Resin Type d d o p d layer B
Degree of butyralization 68.5 68.5 68.5 72.4 68.5 (mol %) Degree of
acetylation 1 1 1.8 1.2 1 (mol %) Amount (parts by weight) 100 100
100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO Amount (parts by
weight) 33 33 36 37.5 35 Layer structure B/A/B B/A/B B/A/B B/A/B
B/A/B Peak temperature of tan .delta. at low-temperature side
(.degree. C.) -4.23 -4.56 -4.22 -5.02 -4.65 Peak maximum value of
tan .delta. at low-temperature side 1.75 1.63 1.7 1.68 1.61 Peak
maximum value of tan .delta. at high-temperature side 0.51 0.53
0.57 0.58 0.57 Loss factor at 20.degree. C. around 3.150 Hz 0.56
0.5 0.52 0.51 0.49 Loss factor at 30.degree. C. around 6.300 Hz 0.2
0.18 0.18 0.18 0.17 Bubble formation test A (state of Bubble
formation) .smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle.
.smallcircle..smallcircle. Bubble formation test B (state of Bubble
formation) .smallcircle. .smallcircle. .smallcircle. .smallcircle.
.smallcircle. Test method A: glass transition temperature (Tg)
(.degree. C.) -3.86 -3.86 -3.86 -3.86 -4.29 Test method A: G' (Tg +
30) (Pa) 229800 229800 229800 229800 227700 Test method A: G' (Tg +
80) (Pa) 158000 158000 158000 158000 180400 Test method A: G' (Tg +
80)/G' (Tg + 30) 0.68 0.68 0.68 0.68 0.70 Test method B: glass
transition temperature (Tg) (.degree. C.) -4.52 -4.88 -4.56 -5.49
-4.87 Test method B: G' (Tg + 30) (Pa) 220700 222200 218900 208100
223700 Test method B: G' (Tg + 80) (Pa) 147100 147900 1488000
140600 157200 Test method B: G' (Tg + 80)/G' (Tg + 30) 0.67 0.67
0.68 0.68 0.70 Proportion of high-molecule-weight component X (%)
-- -- -- -- -- Proportion of high-molecule-weight component Y (%)
-- -- -- -- --
TABLE-US-00005 TABLE 5 Comparative Comparative Comparative Example
Example Example Example Example Example 39 40 41 2 3 4 Intermediate
Resin Type r r r AB AC AD layer A Degree of butyralization (mol %)
45 45 45 63.5 34 30 Degree of acetylation (mol %) 40 40 40 12.8
29.5 29.5 Amount (parts by weight) 100 100 100 100 100 100 Kind of
plasticizer 3GB DBA 3GH 3GO 3GO 3GO Amount of plasticizer (parts by
weight) 40 40 50 60 60 60 Protecting Resin Type AA AA d d d d layer
B Degree of butyralization (mol %) 62.5 52.5 68.5 68.5 68.5 68.5
Degree of acetylation (mol %) 1 1 1 1 1 1 Amount (parts by weight)
100 100 100 100 100 100 Kind of plasticizer 3GB DBA 3GH 3GO 3GO 3GO
Amount of plasticizer (parts by weight) 30 30 26.5 37.5 37.5 37.5
Layer structure B/A/B B/A/B B/A/B B/A/B B/A/B B/A/B Peak
temperature of tan .delta. at low-temperature side (.degree. C.)
-4.27 -4.02 -3.24 -2.43 -2.85 4.22 Peak maximum value of tan
.delta. at low-temperature side 1.85 1.75 1.73 1.03 1.05 1.07 Peak
maximum value of tan .delta. at high-temperature side 0.56 0.55
0.55 0.53 0.53 0.53 Loss factor at 20.degree. C. around 3.150 Hz
0.55 0.54 0.53 0.28 0.28 0.22 Loss factor at 30.degree. C. around
6.300 Hz 0.19 0.18 0.18 0.09 0.09 0.14 Bubble formation test A
(state of Bubble formation) .smallcircle..smallcircle.
.smallcircle..smallcircle. .smallcircle..smallcircle. x x x Bubble
formation test B (state of Bubble formation) .smallcircle.
.smallcircle. .smallcircle. x x x Test method A: glass transition
temperature (Tg) (.degree. C.) -12.58 -11.88 -10.45 1.8 1.98 7.21
Test method A: G' (Tg + 30) (Pa) 184500 187500 211600 236500 237700
265000 Test method A: G' (Tg + 80) (Pa) 123900 128400 143700 142000
143500 163500 Test method A: G' (Tg + 80)/G' (Tg + 30) 0.67 0.68
0.68 0.60 0.60 0.62 Test method B: glass transition temperature
(Tg) (.degree. C.) -5.01 -4.76 -4.14 -3.2 -3.33 3.77 Test method B:
G' (Tg + 30) (Pa) 224700 225600 228300 226000 227300 245700 Test
method B: G' (Tg + 80) (Pa) 150000 150800 153600 131000 132500
148500 Test method B: G' (Tg + 80)/G' (Tg + 30) 0.67 0.67 0.67 0.58
0.58 0.60 Proportion of high-molecule-weight component X (%) -- --
-- -- -- -- Proportion of high-molecule-weight component Y (%) --
-- -- -- -- --
[0233] As shown in Tables 2 to 5, in the intermediate films for
laminated glass in the examples and comparative examples, as the
result of using the resin film B (first layer) containing the
polyvinyl acetal resin constituting the first layer and the
plasticizer constituting the first layer in amounts shown in Tables
2 to 5 and allowing the plasticizers to transfer between the
respective layers of the multilayer intermediate film, and then
measuring the elastic modulus G' of the resin film B (first layer),
the ratio (G'(Tg+80)/G'(Tg+30)) of the resin film a was
substantially the same as the ratio (G'(Tg+80)/G'(Tg+30)) of the
resin film A containing 100 parts by weight of the polyvinyl acetal
resin and 60 parts by weight of the 3GO contained in the first
layer.
EXPLANATION OF SYMBOLS
[0234] 1: intermediate film [0235] 1a: first surface [0236] 1b:
second surface [0237] 2: first layer [0238] 2a: first surface
[0239] 2b: second surface [0240] 3: second layer [0241] 3a: outer
surface [0242] 4: third layer [0243] 4a: outer surface [0244] 11:
laminated glass [0245] 21: first component for laminated glass
[0246] 22: second component for laminated glass
* * * * *