Title of Invention

AN INTERLAYER FILM FOR A LAMINATE GLASS

Abstract An intermediate film with which laminated glass is suitably obtained, the intermediate film having excellent transparency, heat shielding capability, and electromagnetic wave transmission capability even if it is sandwiched between a pair of sheets of glass to produce laminated glass. Further, when the laminated glass is subjected to a durability test by light, a visible light transmission factor is not reduced after the test, initial optical quality is not impaired, and excellent antiweatherability is achieved. The intermediate film for laminated glass has at least one or more of each of heat shielding layers and ultraviolet light shielding layers.
Full Text TECHNICAL FIELD
[0001]
The present invention relates to an interlayer film
for a laminate glass which is excellent in transparency,
heat-shielding property, and electromagnetic wave
transmittance in the case of use for a laminate glass and
is not deteriorated in the initial optical properties even
after a light stability test and a laminate glass obtained
by using the interlayer film for a laminate glass.
BACKGROUND ART
[0002]
Since a laminate glass is scarcely scattered in
debris even if being broken by receiving outside impact and
is thus safe, the laminate glass has been used widely for a
window glass of vehicles such as automobiles; aircrafts;
buildings and the like. Examples of such a laminate glass
are those which are obtained by inserting an interlayer
film for a laminate glass comprising polyvinyl acetal resin
such as polyvinyl butyral resin plasticized by a
plasticizer between at least one pair of glasses and
uniting such a film with glasses.
[0003]
Although the laminate glass using such an interlayer
film for a laminate glass is excellent in safety, it has a
disadvantageous point that it is inferior in heat-shielding
property. Generally, infrared ray (IR) with wavelength at
shortest 780 nm, which is longer than that of visible light,
among the light rays, has energy dose as low as about 10%
of that of ultraviolet (UV) ray but has a significant


thermal effect and if once absorbed in a substance, IR is
released in form of heat to result in temperature increase
and therefore, it is called as thermal beam. Accordingly,
among light rays coming in through a front glass or side
glass of an automobile, if IR having significant thermal
effect is shielded, the heat-shielding effect is increased
and the temperature increase in the inside of the
automobile can be suppressed.
[0004]
As such a glass which shields IR having significant
thermal effect, for example, a heat ray-cutting glass has
been commercialized. The heat ray-cutting glass is
developed aiming to shield direct sun lights and obtained
by forming a multilayer coating of metal/metal oxide on the
surface of a glass plate by metal evaporation, sputtering
or the like. However, such a multilayer coating is
susceptive of scratching from the outside and inferior in
chemical resistance, so that a method of obtaining the
laminate glass laminating an interlayer film of a
plasticized polyvinyl butyral resin film or the like has
been employed.
[0005]
However, the heat ray-cutting glass has problems that
the glass is expensive, deteriorated in the transparency
(visible light transmittance) because of thick thickness of
the multilayer coating, and highly colorized because of
absorption in a visible light region. Further, there are
other problems that the adhesion between the multilayer
coating and the interlayer film is decreased to cause
separation and whitening of the interlayer film and that
the multilayer coating layer inhibits transmittance of
electromagnetic wave and interferes with communication
functions of a mobile phone, a car navigation system, a
garage opener, an electronic toll collection system, and
the like.


[0006]
For example, Patent Document No. 1 and Patent
Document No. 2 proposes a laminate glass obtained by
inserting a polyester film on which a thin film of a metal
and/or metal oxide is formed or evaporated between
plasticized polyvinyl butyral resin sheets. However, these
laminate glasses have a problem in the adhesion between the
plasticized polyvinyl butyral resin sheets and the
polyester film to result in not only separation in the
interfaces but also insufficiency of electromagnetic wave
transmittance.
[0007]
Further, Patent Document No. 3 discloses a method of
obtaining electromagnetic wave transmittance by dispersing
a metal oxide having heat-shielding property in the
interlayer film. However the laminate glass comprising
such an interlayer film for a laminate glass obtained by
the described method has a problem that the laminate glass
is discolored to be yellow to decrease the visible light
transmittance after a durability test to light in some
cases and thus it is expected that the laminate glass is
scarcely allowed for use as an automotive front glass whose
visible light transmittance is regulated in the lower limit.
[0008]
Patent Document No. 1: Japanese Kokoku Publication Sho-61-
52093
Patent Document No. 2: Japanese Kokai Publication Sho-64-
36442
Patent Document No. 3: Japanese Kokai Publication 2001-
302289
DISCLOSURE OF THE INVENTION
PROBLEMS WHICH THE INVENTION IS TO SOLVE
[0009]
In view of the above-mentioned state of the art, the


present invention aims to provide an interlayer film for a
laminate glass which is excellent in transparency, heat-
shielding property, and electromagnetic wave transmittance
in the case of use for a laminate glass and is not
deteriorated in the visible light transmittance and the
initial optical properties even after a durability test to
light and provide a laminate glass comprising the
interlayer film for a laminate glass.
MEANS FOR SOLVING THE OBJECT
[0010]
The present invention is directed to an interlayer
film for a laminate glass which comprises at least each one
layer of a heat-shielding layer and an UV-shielding layer.
Hereinafter, the present invention will be described
in detail.
[0011]
An interlayer film for a laminate glass of the
present invention comprises at least each one layer of a
heat-shielding layer and an UV-shielding layer.
On the basis of results of intensive investigations,
inventors of the present invention have found that a cause
of decrease of visible light transmittance of a laminate
glass comprising an interlayer film containing a heat-
shielding metal oxide dispersed therein after a durability
test to light is attributed to the chemical change of the
metal oxide itself by UV rays and the resin matrix affected
by the chemical change.
That is, it is supposed that when light directly
comes in from outside, the heat-shielding layer of the
interlayer film for a laminate glass of the present
invention is discolored to cause decrease of the visible
light transmittance owing to the light with a wavelength in
UV region having a high energy.
However, since the interlayer film for a laminate


glass of the present invention comprises the above-
mentioned UV-shielding layer having a function of shielding
the UV rays, UV rays of the light coming in the above-
mentioned heat-shielding layer from the UV-shielding layer
side are considerably decreased and thus the discoloration
of the above-mentioned heat-shielding layer by UV rays can
be suppressed. Accordingly, the laminate glass obtained
using the interlayer film for a laminate glass of the
present invention is suppressed from decrease of the
visible light transmittance after the durability test to
light and is not deteriorated in the initial optical
qualities.
[0012]
The interlayer film for a laminate glass of the
present invention is preferable to comprise three layers
composed of at least a heat-shielding layer and UV-
shielding layers formed on both faces of the above-
mentioned heat-shielding layer. With respect to the
interlayer film for a laminate glass with such a structure,
even if light comes in from both sides of the heat-
shielding layer, the light comes in while being transmitted
through the above-mentioned UV-shielding layers, UV rays
are considerably decreased and thus discoloration of the
above-mentioned heat-shielding layer to be yellow can be
prevented. Accordingly, the visible light transmittance is
not decreased even after the durability test to light and
the initial optical qualities are not deteriorated in the
case where the interlayer film for a laminate glass with
the above-mentioned structure is used to obtain a laminate
glass.
[0013]
With respect to the interlayer film for a laminate
glass of the present invention, the above-mentioned heat-
shielding layer is preferable to have an electromagnetic
wave shield capability of 10 dB or lower at a frequency of


0.1 MHz to 26.5 GHz in the case where the heat-shielding
layer is inserted between two plates of glasses selected
from a group consisting of clear glasses, green glasses,
high heat ray absorption glasses, and UV absorption glasses
to obtain a laminate glass. If it exceeds 10 dB, the
electromagnetic wave transmittance of the laminate glass
comprising the interlayer film for a laminate glass of the
present invention may be decreased in some cases.
[0014]
The above-mentioned heat-shielding layer is
preferable to have a haze of 1.0% or less in form of the
above-mentioned laminate glass. If it exceeds 1.0%, the
transparency of the laminate glass comprising the
interlayer film for a laminate glass of the present
invention may be so low as to cause adverse effects on
practical use in some cases.
[0015]
The above-mentioned heat-shielding layer inserted in
the above-mentioned laminate glass is preferable to have a
visible light transmittance of 70% or higher. If it is
lower than 70%, the transparency of the laminate glass
comprising the interlayer film for laminate glass of the
present invention may be so low as to cause adverse effects
on practical use in some cases. The above-mentioned
visible light transmittance may be measured, for example,
by measuring visible light transmittance (Tv) of the
laminate glass to the light rays with wavelength of 380 to
780 nm according to [Testing method on transmittance,
reflectance and emittance offlat glasses and evaluation of
solar heat gain coefficient] of JIS R 3106 (1998) by a
recording spectrophotometer (manufactured by Hitachi Ltd.,
U 4000) .
[0016]
The above-mentioned heat-shielding layer inserted in
the above-mentioned laminate glass is preferable to have a


sun light transmittance 85% or lower of the above-mentioned
visible light transmittance in a wavelength region of 300
to 2100 nm. If it exceeds 85%, the heat-shielding property
of the laminate glass comprising the interlayer film for a
laminate glass of the present invention is sometimes
insufficient. The above-mentioned sun light transmittance
may be measured, for example, by measuring sun light
transmittance (Ts) of the laminate glass to the light rays
with wavelength of 300 to 2100 nm according to [Testing
method on transmittance, reflectance and emittance offlat
glasses and evaluation of solar heat gain coefficient] of
JIS R 3106 (1998) by a recording spectrophotometer
(manufactured by Hitachi Ltd., U 4000) .
[0017]
The above-mentioned heat-shielding layer is
preferable to contain a transparent resin and a heat-
shielding agent.
The above-mentioned transparent resin is not
particularly limited and, for example, resins known as
transparent resins for interlayer films for a laminate
glass can be exemplified. Practical examples of the resin
are polyvinyl acetal resin; polyurethane resin; ethylene-
vinyl acetate resin; acrylic copolymer resin comprising
acrylic acid, methacrylic acid, or their derivatives as
composing units; and vinyl chloride-ethylene-glycidyl
methacrylate copolymer resin. These resins can be produced
easily by known methods or so.
[0018]
As the above-mentioned transparent resin, polyvinyl
acetal resin is preferable. The above-mentioned polyvinyl
acetal resin is not particularly limited if it is obtained
by acetalization of polyvinyl alcohol with an aldehyde. As
the above-mentioned polyvinyl alcohol, a polyvinyl alcohol
obtained by saponification of poly(vinyl acetate) and
having a saponification degree of 80 to 99.8% by mole may


generally be used.
In the case where the above-mentioned polyacetal
resin is used for the present invention, the molecular
weight and molecular weight distribution are not
particularly limited, however in terms of the formability
and physical properties, the lower limit of the
polymerization degree of the polyvinyl alcohol resin to be
a raw material is preferably 200 and the upper limit is
preferably 3,000. If it is lower than 200, the resistance
to penetration of the laminate glass to be obtained tends
to be decreased and if it exceeds 3,000, the formability of
the resin film tends to be worsened and the toughness of
the resin film tend to be too high, resulting in inferior
processibility. The lower limit is more preferably 500 and
the upper limit is more preferably 2,000.
[0019]
As the above-mentioned aldehyde, aldehydes with 1 to
10 carbon atoms may be used and examples of such aldehydes
are n-butylaldehyde, isobutylaldehyde, n-varelaldehyde, 2-
ethylbutylaldehyde, n-hexylaldehyde, n-octylaldehyde, n-
nonylaldehyde, n-decylaldehyde, formaldehyde, acetaldehyde,
and benzaldehyde. Among them, n-butylaldehyde, n-
hexylaldehyde, and n-varelaldehyde are preferable and
butylaldehyde with 4 carbon atoms is particularly
preferable.
[0020]
As the above-mentioned polyvinyl acetal, polyvinyl
butyral obtained by acetalization with butylaldehyde is
preferable. Further, these acetal resins may be properly
combined and blended on consideration of the required
physical properties. Further, co-polyvinyl acetal resin
obtained by combining aldehyde at the time of acetalization
may be used properly. The lower limit of the acetalization
degree of the above-mentioned polyvinyl acetal resin to be
used for the present invention is preferably 40% and the


upper limit is 85%, and the lower limit is more preferably
60% and the upper limit is more preferably 75%.
[0021]
The above-mentioned heat-shielding layer is
preferable to contain a plasticizer.
As the above-mentioned plasticizer, any plasticizer
to be used commonly for the interlayer film for a laminate
glass may be used without any particular limit and examples
of the plasticizer are organic type plasticizers such as
monobasic organic acid esters, polybasic organic acid
esters; and organophosphoric acid type plasticizers such as
organophosphoric acid type, organophosphorous acid type
ones. These plasticizers may be used alone or two or more
of them may be used in combination and on consideration of
the compatibility with the above-mentioned transparent
resin, these plasticizers are properly used depending on
the types of the resin.
[0022]
The above-mentioned monobasic organic acid ester type
plasticizers are not particularly limited and examples
thereof may include glycol type esters obtained by reaction
of glycols such as triethylene glycol, tetraethylene glycol,
tripropylene glycol or the like and a monobasic organic
acid such as butyric acid, isobutyric acid, caproic acid,
2-ethylbutyric acid, heptylic acid, n-octylic acid, 2-
ethylhexylic acid, pelargonic acid (n-nonylic acid), or
decylic acid. Among them, triethylene glycol monobasic
organic acid esters such as triethylene glycol dicaproic
acid ester, triethylene glycol di-2-ethylbutyric acid ester,
triethylene glycol di-n-octylic acid ester, and triethylene
glycol di-2-ethylhexylic acid ester are preferable to be
used.
[0023]
The above-mentioned polybasic organic ester type
plasticizers are not particularly limited and examples


thereof may include esters of polybasic organic acids such
as adipic acid, sebacic acid, or azelaic acid and straight
chain or branched alcohols with 4 to 8 carbon atoms. Among
them, dibutyl sebacic acid ester, dioctyl azelaic acid
ester, dibutylcarbitol adipic acid ester are preferable to
be used.
[0024]
The above-mentioned organic phosphoric acid type
plasticizers are not particularly limited and examples
thereof may include tributoxyethyl phosphate,
isodecylphenyl phosphate, triisopropyl phosphate and the
like.
[0025]
Practical examples of the above-mentioned
plasticizers are triethylene glycol diethylbutyrate,
triethylene glycol diethylhexoate, triethylene glycol
dibutylsebacate and the like.
[0026]
In the above-mentioned heat-shielding layer, the
addition amount of the above-mentioned plasticizers is not
particularly limited and for example, in the case where the
above-mentioned transparent resin is polyvinyl acetal resin,
the lower limit is preferably 20 parts by weight and the
upper limit is preferably 100 parts by weight to 100 parts
by weight of the polyvinyl acetal resin. If it is less
than 20 parts by weight, the resistance to penetration is
sometimes decreased and if it exceeds 100 parts by weight,
bleeding out of the plasticizers probably occurs to lead to
deterioration of the transparency and adhesion of the heat-
shielding layer and significant optical distortion of the
laminate glass to be obtained. The lower limit is more
preferably 30 parts by weight and the upper limit is more
preferably 60 parts by weight.
[0027]
The above-mentioned heat-shielding layer is


preferable to contain an adhesion adjustment agent.
The above-mentioned adhesion adjustment agent is not
particularly limited and an alkali metal salt and/or an
alkaline earth metal salt is preferable to be used. As the
above-mentioned alkali metal salt and/or the alkaline earth
metal salt is not particularly limited and examples thereof
are salts of potassium, sodium, magnesium, and the like.
An acid forming the above-mentioned salt is not
particularly limited and examples of the acid include
organic acids, for example, carboxylic acids such as
octylic acid, hexylic acid, butyric acid, acetic acid, and
formic acid and inorganic acids such as hydrochloric acid,
nitric acid.
[0028]
Among the above-mentioned alkali metal salts and/or
alkaline earth metal salts, alkali metal salts and alkaline
earth metal salts of organic acids having 2 to 16 carbon
atoms are more preferable and magnesium carboxylate having
2 to 16 carbon atoms and potassium carboxylate having 2 to
16 carbon atoms are further preferable.
[0029]
The above-mentioned magnesium carboxylate or
potassium carboxylate of organic acids having 2 to 16
carbon atoms' is not particularly limited and for example,
magnesium acetate, potassium acetate, magnesium propionate,
potassium propionate, magnesium 2-ethylbutanate, potassium
2-ethylbutanate, magnesium 2-ethylhexanate, and potassium
2-ethylhexanate are preferable to be used. These salts may
be used alone or two or more of them are used in
combination.
[0030]
The addition amount of the above-mentioned alkali
metal salt and/or alkaline earth metal salt is not
particularly limited in the above-mentioned heat-shielding
layer and for example, in the case where the above-


mentioned transparent resin is polyvinyl acetal resin, the
lower limit of the addition amount is 0.001 parts by weight
and the upper limit is 1.0 part by weight to 100 parts by
weight of the polyvinyl acetal resin. If it is less than
0.001 parts by weight, the adhesion strength may possibly
be decreased in the circumferential part of the interlayer
film in highly humid atmosphere and if it exceeds 1.0 part
by weight, the adhesion strength becomes too low and the
transparency of the interlayer film is lost in some.cases.
The lower limit is more preferably 0.01 parts by weight and
the upper limit is more preferably 0.2 parts by weight.
[0031]
The above-mentioned heat-shielding agent is not
particularly limited if it is a substance capable of giving
heat-shielding property to the heat-shielding layer and for
example, tin-dope indium oxide fine particles (hereinafter,
referred to as ITO fine particles) are preferable to be
used.
The above-mentioned ITO fine particles are preferable
to be finely and evenly dispersed in the above-mentioned
heat-shielding layer so as to sufficiently exhibit the
effect. Practically, to be finely and evenly dispersed
means the state that the ITO fine particles are dispersed
without causing agglomeration to the extent that the
transparency decrease owing to ITO fine particle addition
cannot be confirmed in the case of observation of the
above-mentioned heat-shielding layer with eyes, in other
words, to the extent that light scattering by the ITO fine
particles scarcely takes place in the visible light region.
More particularly, the above-mentioned ITO fine
particles are preferable to have an average particle
diameter of 80 nm or smaller. If the average particle
diameter exceeds 80 nm, the visible light scattering by the
ITO fine particles becomes significant and the transparency
of the interlayer film for a laminate glass of the present


invention to be obtained may possibly be deteriorated. As
a result, in the case of using the film for a laminate
glass, the haze may be worsened and, for example, highly
advanced transparency required for an automotive front
glass or the like cannot be obtained.
[0032]
The above-mentioned ITO fine particles are preferable
to be dispersed so as to satisfy one or less particle with
a particle diameter of 100 nm or larger per 1 µm2. It
means the dispersion state that in the case where the
above-mentioned heat-shielding layer is photographed and
observed by a transmission electron microscope, no ITO fine
particle with a particle diameter of 100 nm or larger is
observed or when ITO fine particles with a particle
diameter of 100 nm or larger are observed and if one ITO
fine particle with a particle diameter of 100 nm or larger
is set in the center of a frame of 1 µm2, no other ITO
particle with a particle diameter of 100 nm or large is
observed within the frame. Accordingly, if the interlayer
film for a laminate glass of the present invention is used
for a laminate glass, the laminate glass is provided with a
low haze and is excellent in transparency and the entire
interlayer film for a laminate glass of the present
invention is provided with high heat-shielding property.
The observation with the transmission electron microscope
may be carried out, for example, at an acceleration voltage
of 100 kV by employing H-7100 FA model transmission
electron microscope manufactured by Hitachi Ltd.
[0033]
The addition amount of the above-mentioned ITO fine
particles in the above-mentioned heat-shielding layer is
not particularly limited and for example, in the case where
the transparent resin is polyvinyl acetal resin, the lower
limit is preferably 0.1 parts by weight and the upper limit
is preferably 3.0 parts by weight to 100 parts by weight of


the polyvinyl acetal resin. If it is less than 0.1 parts
by weight, no sufficient IR cutting effect may be obtained
and if it exceeds 3.0 parts by weight, the transparency to
the visible light is decreased and the haze is increased in
some cases.
[0034]
In general, the above-mentioned ITO fine particles
are evenly dispersed in an organic solvent and then added
to the above-mentioned polyvinyl acetal resin to finely
disperse the particles in the above-mentioned polyvinyl
acetal resin, and it is preferable that a plasticizer of a
similar type to that of the above-mentioned plasticizer to
be used for the plasticization of the above-mentioned
polyvinyl acetal resin is used as a main dispersant for the
even dispersion.
[0035]
The heat-shielding layer is preferable to further
contain a dispersion stabilizer.
As the above-mentioned dispersion stabilizer, for
example, a coordination compound comprising at least one
kind of atom selected from group consisting of nitrogen,
phosphorus, and chalcogen type atom group as a coordinating
atom of ITO is preferable. Such the coordination compound
is not particularly limited and examples of the
coordination compound are anionic surfactants such as
carboxylate salts, sulfonic acid salts, sulfuric acid ester
salts, phosphoric acid ester salts, polymer type
macromolecules, and condensate polymer type macromolecules;
nonionic surfactants such as ethers, esters, ester ethers,
and nitrogen-containing compounds; cationic surfactants
such as primary to tertiary amine salts, quaternary
ammonium salts, and polyethylene polyamine derivatives; and
amphoteric surfactants such as carboxybetaine,
aminocarboxylic acid salts, sulfobetaine, aminosulfuric
acid esters, and imidazoline. Among them, at least one


selected from a group consisting of sulfuric acid type
ester compounds, phosphoric acid ester type compounds,
ricinoleic acid, polyricinoleic acid, polycarboxylic acid,
polyhydric alcohol type surfactants, polyvinyl alcohol, and
polyvinyl butyral is particularly preferable to be used
since it can efficiently prevent agglomeration of the ITO
fine particles.
[0036]
The addition amount of the above-mentioned dispersion
stabilizer is not particularly limited and for example, in
the case where the transparent resin is polyvinyl acetal
resin, the lower limit is preferably 0.001 parts by weight
and the upper limit is preferably 5.0 parts by weight to
100 parts by weight of polyvinyl acetal resin. If it is
less than 0.001 parts by weight, the effect of the
dispersion stabilizer is scarcely obtained. If it exceeds
5.0 parts by weight, foaming occurs at the time of the
interlayer film formation or foaming occurs and the
adhesion strength between the interlayer film and a glass
becomes too high in the case of a laminate glass formation.
The lower limit is more preferably 0.05 parts by weight and
the upper limit is more preferably 1.0 part by weight, to
1.0 part by weight of the ITO fine particles.
[0037]
With respect to the above-mentioned heat-shielding
layer, the haze can be improved further by adding a
chelating agent and a compound having at least one carboxyl
group to the main dispersant. In this case, the chelating
agent and the compound having at least one carboxyl group
may be mixed with the main dispersant or added separately
to the polyvinyl acetal resin without being mixed with the
main dispersant.
[0038]
The above-mentioned chelating agent is not
particularly limited and EDTAs and J3-diketones such as


acetylacetone, benzoyltrifluoroacetone, dipivaloylmethane
can be exemplified and those having good compatibility with
the plasticizer and polyvinyl acetal resin are preferable.
Among them, the above-mentioned β-diketones are preferable
and particularly acetylacetone is preferable. The effect
of addition of these chelating agents is considered that
the agents are coordinated with the above-mentioned ITO
fine particles and therefore, the ITO fine particles are
prevented from agglomeration to result in good dispersion
state and improvement of the haze.
[0039]
The addition amount of the above-mentioned chelating
agent is not particularly limited and for example, in the
case where the above-mentioned transparent resin is
polyvinyl acetal resin, the lower limit is preferably 0.001
parts by weight and the upper limit is preferably 2 parts
by weight to 100 parts by weight of polyvinyl acetal resin.
If it is less than 0.001 parts by weight, the effect of the
addition is scarcely expected and if it exceeds 2 parts by
weight, foaming may occur at the time of film formation or
foaming may occur at the time of a laminate glass
production. The lower limit is more preferably 0.01 parts
by weight and the upper limit is more preferably 1 part by
weight.
[0040]
The above-mentioned compound having one or more
carboxyl groups is not particularly limited and for example,
aliphatic carboxylic acids, aliphatic dicarboxylic acids,
aromatic carboxylic acids, aromatic dicarboxylic acids, and
hydroxyacids can be exemplified. Practically, benzoic acid,
phthalic acid, salicylic acid, ricinoleic acid or the like
may be used. Among them, aliphatic C2 to C18 carboxylic
acids are preferably used and aliphatic C2 to C10 carboxylic
acids are even more preferably used. Practically, acetic
acid, propionic acid, n-butyric acid, 2-ethylbutyric acid,


n-hexanoic acid, 2-ethylhexanoic acid, and n-octanoic acid
can be exemplified.
[0041]
The addition amount of the above-mentioned compound
having one ore more carboxylic groups is not particularly
limited and for example, in the case where the above-
mentioned transparent resin is polyvinyl acetal resin, the
lower limit is preferably 0.001 parts by weight and the
upper limit is preferably 2 parts by weight to 100 parts by
weight of polyvinyl acetal resin. If it is less than 0.001
parts by weight, the effect of the addition is scarcely
expected and if it exceeds 2 parts by weight, discoloration
of the heat-shielding layer may possibly occur and the
adhesion strength of a glass and heat-shielding layer may
be decreased. The lower limit is more preferably 0.01
parts by weight and the upper limit is more preferably 1
part by weight.
[0042]
The above-mentioned heat-shielding layer is
preferable to contain an antioxidant.
The above-mentioned antioxidant is not particularly
limited and for example, as a phenol type, 2, 6-di-tert-
butyl-p-cresol (BHT) (manufactured by Sumitomo Chemical Co.,
Ltd., Sumilizer BHT), tetrakis-[methylene-3-(3',5'-di-tert-
butyl-4'-hydroxyphenyl)propionate]methane (manufactured by
Ciba-Geigy Corp., Irganox 1010) can be exemplified. These
antioxidants may be used alone or two or more of them can
be used in combination.
[0043]
The addition amount of the above-mentioned
antioxidant is not particularly limited and for example, in
the case where the above-mentioned transparent resin is
polyvinyl acetal resin, the lower limit is preferably 0.01
parts by weight and the upper limit is preferably 5.0 parts
by weight to 100 parts by weight of polyvinyl acetal resin.


If it is less than 0.01 parts by weight, the oxidation
prevention effect is scarcely expected and if it exceeds
5.0 parts by weight, foaming may occur at the time of film
formation of interlayer film or foaming may occur at the
time of a laminate glass production.
[0044]
In the interlayer film for a laminate glass of the
present invention, the above-mentioned UV shielding layer
is preferable to have an UV transmittance of 60% or,lower
measured in accordance with SAE J1796 in the case where the
UV-shielding layer is inserted between two plates of
glasses selected from a group consisting of clear glasses,
green glasses,' high heat ray absorption glasses, and UV
absorption glasses to obtain a laminate glass. If it
exceeds 60%, the visible light transmittance is decreased
after a durable test to light in the case of a laminate
glass comprising the UV-shielding layer and the laminate
glass cannot be used for an automotive front glass whose
visible light transmittance has an allowable lower limit
and may not be used practically. It is more preferably 30%
or lower and even more preferably 10% or lower.
[0045]
The above-mentioned UV-shielding layer is preferable
to contain transparent resin and an UV-cutting agent.
The above-mentioned transparent resin is not
particularly limited and for example, those similar to the
transparent resin for the above-mentioned heat-shielding
layer can be exemplified.
[0046]
The above-mentioned UV-cutting agent is preferably at
least one UV absorbent selected from a group consisting of
metal type, metal oxide type, benzotriazole type,
benzophenone type, triazine type, benzoate type, malonic
acid ester type, and oxalic acid anilide type ones. These
UV absorbents may be used alone or two or more of them are


used in combination.
[0047]
The above-mentioned metal type UV absorbent is not
particularly limited and examples of the agent include
platinum ultrafine particles, fine particles obtained by
coating the surface of platinum ultrafine particles with
silica, palladium ultrafine particles, and fine particles
obtained by coating the surface of palladium ultrafine
particles with silica.
[0048]
The above-mentioned metal oxide type UV absorbent is
not particularly limited and examples of the agent include
zinc oxide and/or titanium oxide, cerium oxide and the like.
Among them, zinc oxide and/or titanium oxide is preferable.
[0049]
The above-mentioned metal oxide type UV absorbent is
preferably coated with an insulating metal oxide on the
surface so as to suppress deterioration of the interlayer
film for a laminate glass of the present invention.
The above-mentioned insulating metal oxide is not
particularly limited and for example, those having a band
gap energy of 5.0 eV or higher such as silica, alumina, and
zirconia are exemplified and among them, silica is
preferable to be used.
[0050]
As above-mentioned the metal oxide type UV absorbent
coated with silica, usable examples thereof may be those
which are commonly commercialized and those which are
obtained by treating the above-mentioned metal oxide type
UV absorbent with a reagent capable of forming a silica
layer on the surface by reaction with the surface of the
agent. The above-mentioned reagent capable of forming a
silica layer on the surface is not particularly limited and
for example, tetraethoxysilane, silicon chloride or the
like can be exemplified.


[0051]
Further, the above-mentioned metal oxide type UV
absorbent is preferable to be coated with a hydrolyzable
organosilicon compound on the surface.
As the metal oxide type UV absorbent coated with the
hydrolyzable organosilicon compound on the surface, usable
examples thereof may include those which are commonly
commercialized and those which are obtained by treating the
surface of the above-mentioned metal oxide type UV
absorbent with a silane coupling agent.
[0052]
Further, the above-mentioned metal oxide type UV
absorbent is preferable to be coated with a silicone type
compound on the surface.
As the metal oxide type UV absorbent coated with the
silicone type compound on the surface, usable examples
thereof may include those which are commonly commercialized
and those which are obtained by treating the surface of the
above-mentioned metal oxide type UV absorbent with Methicon,
Dimethicon and the like.
[0053]
As the above-mentioned benzotriazole type UV
absorbent, examples thereof include benzotriazole type ones
such as 2-(2'-hydroxy-5'-methylphenyl) benzotriazole
(manufactured by Ciba-Geigy Corp., Tinuvin P), 2-(2'-
hydroxy-3',5'-di-tert-butylphenyl)benzotriazole
(manufactured by Ciba-Geigy Corp., Tinuvin 320), 2-(2'-
hydroxy-3'-tert-butyl-5'-methylphenyl)-5-
chlorobenzotriazole (manufactured by Ciba-Geigy Corp.,
Tinuvin 326), and 2-(2'-hydroxy-3',5'-di-
amylphenyl)benzotriazole (manufactured by Ciba-Geigy Corp.,
Tinuvin 328) ; and hindered amine type ones such as LA-57
manufactured by Adeka Argus Chemical Co., Ltd.
[0054]
As the above-mentioned benzophenone type UV absorbent,


examples thereof may include octabenzone (manufactured by
Ciba-Geigy Corp., Chimassorb 81).
[0055]
As the above-mentioned triazine type UV absorbent,
examples thereof may include 2-(4,6-diphenyl-l,3,5-triazin-
2-yl)-5-[(hexyl)oxy]-phenol (manufactured by Ciba-Geigy
Corp., Tinuvin 1577 FF).
[0056]
As the above-mentioned benzoate type UV absorbent,
examples thereof may include 2,4-di-tert-butylphenyl-3,5-
di-tert-butyl-4-hydroxybenzoate (manufactured by Ciba-Geigy
Corp., Tinuvin 120).
[0057]
As the above-mentioned malonic acid ester type UV
absorbent, commercialized examples thereof may include
propanedioic acid, [(4-methoxyphenyl)-methylene]-dimethyl
ester (manufactured by Clariant Inc., Hostavin PR-25).
[0058]
As the above-mentioned oxalic acid anilide type UV
absorbent, commercialized examples thereof may include 2-
ethyl-2'-ethoxyoxyanilide (manufactured by Clariant Inc.,
Sanduvor VSU).
[0059]
The above-mentioned malonic acid ester type and
oxalic acid anilide type UV absorbents have an UV
absorption region in UV-B and in consideration of that the
wavelength of UV rays causing deterioration of various
transparent resins is in 300 to 320 nm, it can be said that
these agents are suitable UV absorbents for protection of
the resins from UV rays. Further, since the molar
absorption is extremely high, as compared with a
conventionally known UV absorbent, the UV absorption amount
for the same addition amount is much higher and further
since the molecular weight is low, the addition amount can
be saved to result in cost down.

[0060]
As the above-mentioned UV-cutting agent, use of the
above-mentioned malonic acid ester type and/or oxalic acid
anilide type UV absorbent can keep the decrease of visible
light transmittance of the interlayer film for a laminate
glass of the present invention in a prescribed range or
lower after the durability test to light, which will be
described later.
[0061]
The addition amount of the above-mentioned UV-cutting
agent is not particularly limited and the lower limit is
preferably 0.01 parts by weight and the upper limit is
preferably 5.0 parts by weight to 100 parts by weight of
the transparent resin. If it is less than 0.01 parts by
weight, the UV absorption effect is scarcely obtained and
if it exceeds 5.0 parts by weight, a problem of weathering-
resistance deterioration of the resin may occur in some
cases. The lower limit is more preferably 0.05 parts by
weight and the upper limit is more preferably 1.0 part by
weight.
[0062]
The above-mentioned UV-shielding layer may further
contain, for example, an antioxidant and various types of
photostabilizers as other additives to prevent
deterioration by heat in an extruder. Further, based on
the necessity, modified silicone oil and a surfactant as an
adhesion strength adjustment agent, a flame retarding agent,
an antistatic agent, an adhesion strength adjustment agent,
a moisture resistance agent, a heat ray reflecting agent,
and a heat ray absorbent may be added as additives.
[0063]
The above-mentioned photostabilizers are not
particularly limited and may include hindered amine type
ones, for example, Adeka Stab LA-57 manufactured by Asahi
Denka Co., Ltd.

[0064]
The above-mentioned modified silicone oil is not
particularly limited and may include, for example, epoxy-
modified silicone oil, ether-modified silicone oil, ester-
modified silicone oil, amine-modified silicone oil, and
carboxyl-modified silicone oil disclosed in Japanese Kokoku
Publication Sho-55-29950. These modified silicon oils are
generally liquids obtained by reaction of polysiloxanes
with compounds for modification. The above-mentioned
modified silicone oils may be used alone and two or more of
them are used in combination.
[0065]
The lower limit of the molecular weight of the above-
mentioned modified silicone oil is preferably 800 and the
upper limit is preferably 5,000. If it is lower than 800,
the localization on the surface is sometimes lowered and if
it exceeds 5,000, the compatibility with the resin becomes
inferior to result in bleeding out of the oil to the film
surface and decrease of adhesion strength to the glass.
The lower limit is more preferably 1,500 and the upper
limit is more preferably 4,000.
[0066]
The addition amount of the modified silicone oil is
not particularly limited and, for example, in the case
where the above-mentioned transparent resin is polyvinyl
acetal resin, the lower limit is preferably 0.01 parts by
weight and the upper limit is preferably 0.2 parts by
weight to 100 parts by weight of the polyvinyl acetal resin.
If it is less than 0.01 parts by weight, the effect for
preventing whitening owing to moisture absorption is
scarcely obtained and if it exceeds 0.2 parts by weight,
compatibility with the resin becomes inferior to result in
bleeding out of the oil to the film surface and decrease of
adhesion strength to the glass. The lower limit is more
preferably 0.03 parts by weight and the upper limit is more

preferably 0.1 parts by weight.
[0067]
The above-mentioned surfactant is not particularly
limited and, for example, sodium laurate and
alkylbenzenesulfonic acid can be exemplified.
[0068]
The interlayer film for a laminate glass of the
present invention comprising at least each one layer of
such heat-shielding layer and UV-shielding layer is,, that a
visible light transmittance decrease is preferably 1.0% or
lower measured in accordance with JIS Z 8722 and JIS R 3106
(1998) after the interlayer film is inserted between two
plates of glasses selected from a group consisting of clear
glasses, green glasses, high heat ray absorption glasses,
and UV absorption glasses to obtain a laminate glass; and
Super Xenon 100-hours radiation test is run for the
laminate glass. If it exceeds 1.0%, the visible light
transmittance decrease after the durability test to light
is too significant and it results in a problem for-
practical use.
[0069]
Further, the interlayer film for a laminate glass of
the present invention comprising at least each one layer of
such heat-shielding layer and UV-shielding layer is that a
visible light transmittance decrease is preferably 3.0% or
lower measured in accordance with JIS Z 8722 and JIS R 3106
(1998) after the interlayer film is inserted between two
plates of glasses selected from a group consisting of clear
glasses, green glasses, high heat ray absorption glasses,
and UV absorption glasses to obtain a laminate glass; and
Super UV 300-hours radiation test is run for the laminate
glass. If it exceeds 3.0%, the visible light transmittance
decrease after the durability test to light is too
significant and it results in a problem for practical use.
The upper limit is more preferably 2.0% and even more

preferably 1.0%.
[0070]
Further, in the case where a laminate glass is
produced using the interlayer film for a laminate glass of
the present invention, the increase ratio of yellow index
(YI) and the alteration ratio of b* value of CIE color
system are preferable to be low after the Super Xenon 100-
hours radiation test and Super UV 300-hours radiation test.
If the alteration ratios of the yellow index (YI) and the
b* value of CIE color system are higher, the heat-shielding
agent of such as ITO fine particles and/or the transparent
resin contained in the above-mentioned heat-shielding layer
is considerably deteriorated and the optical properties,
mechanical properties, and physical properties of the
interlayer film for a laminate glass of the present
invention cannot be sometimes maintained after the above-
mentioned test.
[0071]
The thickness of the interlayer film for a laminate
glass of the present invention is not particularly limited
and in terms of the lowest limits of needed penetration
resistance and weathering-resistance, the lower limit is
preferably 0.3 mm and the upper limit is preferably 0.8 mm.
Based on the necessity of improvement of the penetration
resistance or the like, the interlayer film for a laminate
glass of the present invention and an interlayer film for a
laminate glass other than the former may be laminated for
combination use.
[0072]
A method of producing the interlayer film for a
laminate glass of the present invention is not particularly
limited and there are methods, for example, involving
forming the above-mentioned heat-shielding layer and the
UV-shielding layer in sheet-like form by conventional film
formation method such as an extrusion method, a calender

method, a press method and then laminating obtained sheets
and a more preferable method is an extrusion method
involving extrusion in biaxial direction and according to
such a method, the haze of the interlayer film for a
laminate glass to be obtained can further be improved.
[0073]
The method for obtaining the above-mentioned heat-
shielding layer is not particularly limited, however a
method involving adding a dispersion containing the heat-
shielding agent such as ITO fine particles evenly dispersed
in an organic solvent to the transparent resin and then
kneading the mixture may be generally employed.
The organic solvent for the above-mentioned
dispersion is not particularly limited and a plasticizer of
a similar type to the plasticizer to be used is preferable.
The apparatus to be used for mixing the ITO fine
particles and the organic solvent is not particularly
limited and, for example, a planetary type stirring
apparatus, a wet mechanochemical apparatus, a Henshel mixer,
a homogenizer, an ultrasonic radiation apparatus and the
like is used commonly.
[0074]
The apparatus to be used for kneading is not
particularly limited and, for example, an extruder, a
plastograph, a kneader, a Bumbury's mixer, a calender roll,
or the like can be exemplified. Among them, in terms of
continuous production, the extruder is preferable.
[0075]
The method for obtaining the above-mentioned UV-
shielding layer is not particularly limited and in general,
a method of adding an UV-cutting agent in place of the
heat-shielding agent of ITO fine particles and the like in
the above-mentioned method for obtaining the heat-shielding
layer may be employed.
[0076]

Since the interlayer film for a laminate glass of the
present invention comprises at least each one layer of the
heat-shielding layer excellent in transparency, heat-
shielding property, and electromagnetic wave transmittance
and UV-shielding layer excellent in the UV-shielding
efficiency, use of the interlayer film for a laminate glass
of the present invention makes it possible to obtain a
laminate glass excellent in transparency, heat-shielding
property, and electromagnetic wave transmittance and
scarcely deteriorated in the initial optical properties
even after a light stability test.
The present invention also provides a laminate glass
comprising the interlayer film for a laminate glass of the
present invention.
[0077]
With respect to the laminate glass of the present
invention, in general, the interlayer film for a laminate
glass of the present invention is preferable to be disposed
in such a manner that the UV-shielding layer is in the
outside light incident side in relation to the heat-
shielding layer.
As described above, the weathering-resistance of the
above-mentioned heat-shielding layer is rather considerably
affected by the weathering-resistance of the heat-shielding
agent such as ITO fine particles contained therein.
Therefore, when the outside light rays directly enter in
the above-mentioned heat-shielding layer, it may be
considered that the heat-shielding agent such as above-
mentioned ITO fine particles and the dispersion stabilizer
causes chemical change owing to the light rays with
wavelength in the UV wavelength region having high energy,
and at the same time affects even the resin matrix in the
peripheral parts to result in weathering-resistance
decrease. Accordingly, arrangement of the above-mentioned
UV-shielding layer in the outside light ray incident side

in relation to the above-mentioned heat-shielding layer
decreases the dose of the light rays with wavelength in the
UV wavelength region which enter in the above-mentioned
heat-shielding layer and thus prevents the weathering-
resistance deterioration of the heat-shielding layer. As a
result, deterioration of the weathering-resistance of the
laminate glass of the present invention can be suppressed.
[0078]
The glass to be used for the laminate glass of the
present invention is not particularly limited and for
example, commonly used a transparent plate glass can be
exemplified. Particularly, a heat ray absorption glass
with total transmittance of 65% or less in the wavelength
region of 900 to 1,300 nm is preferable. It is because the
IR-cutting property of the ITO fine particles is better in
a wavelength region longer than 1,300 nm and relatively low
in a wavelength region of 900 to 1,300 nm and accordingly,
a combination of the interlayer film for a laminate glass
of the present invention with the above-mentioned heat ray
absorption glass can lower the solar radiation
transmittance and increase the solar radiation cutting
ratio for the same visible light transmittance as compared
with a combination of the interlayer film with clear
glasses.
[0079]
The laminate glass of the present invention may
include combination of the interlayer film for a laminate
glass of the present invention and a plastic film. In
particular, for example, combinations of the interlayer
film for a laminate glass of the present invention with
transparent plastic films of polycarbonates, poly(methyl
methacrylate), and the like having no metal coating layer
are exemplified. Such a laminate glass is obtained using
the interlayer film for a laminate glass of the present
invention and thus is excellent in transparency, heat-

shielding property, and electromagnetic wave transmittance
and scarcely causes deterioration of the initial optical
properties even after the light stability test and
additionally, since the laminate glass comprises the
plastic film, the crime prevention and penetration
properties can be improved.
Further, a rigid body other than a glass, for example,
a metal, an inorganic material, or the like may be used as
vibration suppressing material by laminating it on the
interlayer film for a laminate glass of the present
invention.
[0080]
The laminate glass of the present invention can be
used for an automotive front glass, a side glass, glass
parts for vehicles such as aircrafts and trains, glasses
for buildings, and the like. Further, as the interlayer
film for a laminate glass, multilayer type interlayer film
for a laminate glass having a multilayer structure can be
used and for example, the multilayer type interlayer film
for a laminate glass can be used as a multilayer type
sound-insulating interlayer film for a laminate glass and a
functional laminate glass.
EFFECT OF THE INVENTION
[0081]
Since the interlayer film for a laminate glass of the
present invention comprises at least each one layer of
heat-shielding layers and UV-shielding layers, the
interlayer film for a laminate glass is excellent in the
transparency, the heat shielding property, and
electromagnetic wave transmittance in the case of use for a
laminate glass and scarcely causes visible light
transmittance decrease even after a durable test to light
and doesnot deteriorate the initial optical quality.

BEST MODE FOR CARRYING OUT THE INVENTION
[0082]
Hereinafter, the present invention will be described
in details with reference to examples, however the present
invention is not limited to these examples.
[0083]
(Example 1)
(1) Synthesis of polyvinyl butyral
275 g of polyvinyl alcohol with an average
polymerization degree of 1,700 and a saponification degree
of 99.2% by mole was added to and dissolved in pure water
2,890 g by heating. The reaction system was adjusted to be
at 15°C and 201 g of hydrochloric acid with a concentration
35% by weight and 157 g of n-butylaldehyde were further
added and kept at the same temperature to precipitate a
reaction product. Next, the reaction system was kept at
60°C for 3 hours to finish the reaction and then the
reaction system was washed with an excess amount of water
to wash out unreacted n-butylaldehyde and the hydrochloric
acid catalyst was neutralized with an aqueous sodium
hydroxide solution, a widely used neutralization agent, and
further the reaction product was washed with excess water
for 2 hours and dried to obtain a white powder state
polyvinyl butyral resin. The polyvinyl butyral resin had
an average butyralization degree of 68.5% by mole.
[0084]
(2) Production of plasticizer mixed with UV-cutting agent
and antioxidant
As an antioxidant, 0.8 parts by weight of 2,6-di-
tert-butyl-p-cresol (BHT) (manufactured by Sumitomo
Chemical Co., Ltd., Sumilizer BHT), and as an UV absorbent,
0.8 parts by weight of 2-(2'-hydroxy-3'-tert-butyl-5'-
methylphenyl)-5-chlorobenzotriazole (manufactured by Ciba-
Geigy Corp., Tinuvin 326), were added to 40 parts by weight
of triethylene glycol di-ethylenebutylate (3G0) and stirred

and mixed until the mixture became a uniform and
transparent solution to obtain a plasticizer solution.
[0085]
(3) Production of ITO-dispersed plasticizer
1 part by weight of an ITO powder (manufactured by
Mitsubishi Materials Corp.) was loaded to 40 parts by
weight of the obtained plasticizer solution and using a
polyphosphoric acid ester salt as a dispersant, the ITO
fine particles are dispersed in the plasticizer by a
horizontal raicrobeads mill.
After that, 0.2 parts by weight of acetylacetone was
added to the solution while being stirred to obtain an ITO-
dispersed plasticizer solution.
[0086]
(4) Production of heat-shielding layer
41 parts by weight of the ITO-dispersed plasticizer
solution was added to 100 parts by weight of the obtained
polyvinyl butyral resin and magnesium 2-ethylbutyrate in a
proper amount was added thereto so as to adjust the Mg
content to be 60 ppm in the entire system and the resulting
mixture was sufficiently melted and kneaded by a mixing
roll and press-molded at 150°C for 30 minutes by employing
a press molding apparatus to obtain a heat-shielding layer
(A) with an average film thickness of 0.76 mm.
[0087]
(5) Production of UV-shielding layer
40 parts by weight of the plasticizer solution was
added to 100 parts by weight of the obtained polyvinyl
butyral resin and magnesium 2-ethylbutyrate in a proper
amount was added thereto so as to adjust the Mg content to
be 60 ppm in the entire system and the resulting mixture
was sufficiently melted and kneaded by a mixing roll and
press-molded at 150°C for 30 minutes by employing a press
molding apparatus to obtain a UV-shielding layer (A) with
an average film thickness of 0.76 mm.

[0088]
(6) Production of laminate glass
An interlayer film for a laminate glass with two-
layer structure obtained by laminating each one layer of
obtained heat-shielding layer (A) and UV-shielding layer
(A) was sandwiched by setting transparent float glass
plates (length 30 cm x width 30 cm x thickness 2.5 mm) from
both ends and the laminate body was put in a rubber bag and
degassed at 2660 Pa (20 torr) vacuum degree for 20 minutes
and then the laminate body was transferred to an oven while
being degassed and kept at 90°C for 30 minutes and vacuum-
pressed. The laminate glass preliminarily press-bonded in
such a manner was pressure bonded under the condition of
135°C and pressure of 1.2 MPa (12 kg/cm2) for 20 minutes in
an autoclave to obtain a laminate glass.
[0089]
(Example 2)
A heat-shielding layer (B) was produced in the same
manner as Example 1, except that 2 parts by weight of ITO
powder (manufactured by Mitsubishi Materials Corp.) was
loaded to 40 parts by weight of the plasticizer obtained in
the ITO-dispersed plasticizer production and the average
film thickness of the heat-shielding layer was changed to
be 0.38 mm.
[0090]
A laminate glass was obtained in the same manner as
Example 1, except that the heat-shielding layer (B) and the
UV-shielding layer (A) produced in the same manner as
Example 1 were used.
[0091]
(Example 3)
A heat-shielding layer (B) was produced in the same
manner as Example 1, except that 0.2 parts by weight of
2,6-di-tert-butyl-p-cresol (BHT) (manufactured by Sumitomo
Chemical Co., Ltd., Sumilizer BHT) was used as an

antioxidant and 0.2 parts by weight of 2-(2'-hydroxy-3'-
tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole
(manufactured by Ciba-Geigy Corp., Tinuvin 326), was used
as an UV-absorbent in the production of the UV-shielding
layer.
[0092]
A laminate glass was obtained in the same manner as
Example 1, except that the heat-shielding layer (A)
produced in the same manner as Example 1 and the UV-
shielding layer (B) were used.
[0093]
(Example 4)
A laminate glass was obtained in the same manner as
Example 1, except that the heat-shielding layer (B)
produced in the same manner as Example 2 and the UV-
shielding layer (B) produced in the same manner as Example
3 were used.
[0094]
(Example 5)
A laminate glass was obtained in the same manner as
Example 1, except that the interlayer -film for a laminate
glass with a three-layer structure was produced by forming
the UV-shielding layers (A) produced in the same manner as
Example 1 on both faces of the heat-shielding layer (A)
produced in the same manner as Example 1.
[0095]
(Example 6)
A laminate glass was obtained in the same manner as
Example 1, except that the interlayer film for a laminate
glass with a three-layer structure was produced by forming
the UV-shielding layers (A) produced in the same manner as
Example 1 on both faces of the heat-shielding layer (B)
produced in the same manner as Example 2.
[0096]
(Example 7)

A laminate glass was obtained in the same manner as
Example 1, except that the interlayer film for a laminate
glass with a three-layer structure was produced by forming
the UV-shielding layers (B) produced in the same manner as
Example 3 on both faces of the heat-shielding layer (A)
produced in the same manner as Example 1.
[0097]
(Example 8)
A laminate glass was obtained in the same manner as
Example 1, except that the interlayer film for a laminate
glass with a three-layer structure was produced by forming
the UV-shielding layers (B) produced in the same manner as
Example 3 on both faces of the heat-shielding layer (B)
produced in the same manner as Example 2.
[0098]
(Example 9)
An UV-shielding layer (C) was produced in the same
manner as Example 1, except that ZnO fine particles
(average particle diameter 80 nm) coated with silica were
used as the UV-cutting agent in the production of the UV-
shielding layer.
[0099]
A laminate glass was obtained in the same manner as
Example 1, except the heat-shielding layer (A) produced in
the same manner as Example 1 and the UV-shielding layer (C)
were used.
[0100]
(Example 10)
A laminate glass was obtained in the same manner as
Example 1, except the heat-shielding layer (B) produced in
the same manner as Example 2 and the UV-shielding layer (C)
produced in the same manner as Example 9 were used.
[0101]
(Example 11)
An UV-shielding layer (D) was produced in the same

manner as Example 1, except that CeO2 fine particles
(average particle diameter 80 nm) were used as the UV-
cutting agent in the production of the UV-shielding layer.
[0102]
A laminate glass was obtained in the same manner as
Example 1, except the heat-shielding layer (A) produced in
the same manner as Example 1 and the UV-shielding layer (D)
were used.
[0103]
(Example 12)
A laminate glass was obtained in the same manner as
Example 1, except the heat-shielding layer (B) produced in
the same manner as Example 2 and the UV-shielding layer (D)
produced in the same manner as Example 9 were used.
[0104]
(Example 13)
A laminate glass was obtained in the same manner as
Example 1, except the interlayer film for a laminate glass
with a three-layer structure was produced by forming the
UV-shielding layers (C) produced in the same manner as
Example 9 on both faces of the heat-shielding layer (A)
produced in the same manner as Example 1.
[0105]
(Example 14)
A laminate glass was obtained in the same manner as
Example 1, except the interlayer film for a laminate glass
with a three-layer structure was produced by forming the
UV-shielding layers (C) produced in the same manner as
Example 9 on both faces of the heat-shielding layer (B)
produced in the same manner as Example 2.
[0106]
(Example 15)
A laminate glass was obtained in the same manner as
Example 1, except the interlayer film for a laminate glass
with a three-layer structure was produced by forming the

UV-shielding layers (D) produced in the same manner as
Example 11 on both faces of the heat-shielding layer (A)
produced in the same manner as Example 1.
[0107]
(Example 16)
A laminate glass was obtained in the same manner as
Example 1, except the interlayer film for a laminate glass
with a three-layer structure was produced by forming the
UV-shielding layers (D) produced in the same manner as
Example 11 on both faces of the heat-shielding layer (B)
produced in the same manner as Example 2.
[0108]
(Example 17)
An UV-shielding layer (E) was produced in the same
manner as Example 1, except that a malonic acid ester type
UV absorbent (propanedioic acid, [(4-methoxyphenyl)-
methylene]-dimethyl ester (manufactured by Clariant Inc.,
Hostavin PR-25)) was used as the UV-cutting agent in the
production of the UV-shielding layer.
A laminate glass was obtained in the same manner as
Example 1, except the heat-shielding layer (A) produced in
the same manner as Example 1 and the UV-shielding layer (E)
were used.
[0109]
(Example 18)
A laminate glass was obtained in the same manner as
Example 1, except the interlayer film for a laminate glass
with a three-layer structure was produced by forming the
UV-shielding layers (E) produced in the same manner as
Example 17 on both faces of the heat-shielding layer (A)
produced in the same manner as Example 1.
[0110]
(Comparative Example 1)
The heat-shielding layer (A) was produced in the same
manner as Example 1 and a laminate glass was obtained using

only the obtained heat-shielding layer (A) in the same
manner as Example 1.
[0111]
(Comparative Example 2)
The heat-shielding layer (B) was produced in the same
manner as Example 2 and a laminate glass was obtained using
only the obtained heat-shielding layer (B) in the same
manner as Example 1.
[0112]
The heat-shielding layers (A) and (B) produced in the
respective Examples and Comparative Examples were subjected
to evaluations of electromagnetic wave shielding property,
haze, visible light transmittance, and solar radiation
transmittance, and UV-shielding layers (A) to (E) were
subjected to evaluations of UV transmittance, and the
laminate glasses obtained in the respective Examples and
Comparative Examples were subjected to evaluations of the
weathering-resistance test according to the following
methods.
[0113]
(1) Electromagnetic wave shielding property of heat-
shielding layer
With respect to each laminate glass produced by
separately sandwiching the heat-shielding layers (A) and
(B) with clear glasses, the reflection loss value (dB) in a
range of 0.1 to 10 MHz was compared with that of a common
float glass single plate with a thickness of 2.5 mm by an
electromagnetic wave transmittance KEC measurement method
(peripheral field electromagnetic wave shielding effect
measurement) and the minimum and maximum values of the
difference at the above-mentioned frequency were recorded.
The reflection loss value (dB) in a range of 2 to 26.5 GHz
was measured by uprightly setting each sample of 600 mm
square-size between a pair of antennas for transmission and
reception and receiving electric wave from an electric wave

signal generator by the spectrum analyzer to evaluate the
shielding property of each sample (far field
electromagnetic wave measurement method). The results are
shown in Table 1.
[0114]
(2) Haze of heat-shielding layer
With respect to each laminate glass produced by
separately sandwiching the heat-shielding layers (A) and
(B) with clear glasses, measurement was carried out., in
accordance with JIS K 6714. The results are shown in Table
1.
[0115]
(3) Visible light transmittance and solar radiation
transmittance of heat-shielding layer
With respect to each laminate glass produced by
separately sandwiching the heat-shielding layers (A) and
(B) with clear glasses, the visible light transmittance in
a wavelength region of 380 to 780 nm was measured in
accordance with JIS Z 8722 and JIS R 3106 (1998) by using a
recording spectrophotometer (manufactured by Shimadzu
Corporation, U 4000). Also, the solar radiation
transmittance in a wavelength region of 300 to 2100 nm was
measured and the ratio thereof to the visible light
transmittance was calculated. The results are shown in
Table 1.
[0116]
(4) UV transmittance of UV-shielding layer
With respect to each laminate glass produced by
separately sandwiching the UV-shielding layers (A) to (E)
with clear glasses, the UV transmittance was measured in
accordance with SAE J1796. The results are shown in Table
2.
[0117]
(5) Weathering-resistance test of laminate glass
With respect to each laminate glass produced in the

respective Examples and Comparative Examples, the visible
light transmittance in a wavelength region of 380 to 780 nm
was measured in accordance with JIS Z 8722 and JIS R 3106
(1998) by using a recording spectrophotometer (manufactured
by Shimadzu Corporation, U 4000) . Also, the measurement
was also carried out in the same manner after S-Xenon
(Super Xenon) radiation test and ATv was calculated by
comparison with the measurement result before radiation
according to the following equation (1). The results are
shown in Table 3.
Further, measurement was carried out so that the
first layer in the light incident side is set to be a UV-
shielding layer.
[0118]
ATv = Tv (after S-Xenon radiation) - Tv (before S-Xenon
radiation) (1)
[0119]
Super Xenon (S-Xenon) radiation test
Each radiation sample of 5 x 10 cm was produced and
subjected to the S-Xenon radiation test under the following
conditions:
testing apparatus: Super-Xenon Weather meter (SX 75,
manufactured by Suga Test Instruments Co., Ltd.);
UV intensity: 180 mW/m2;
limited wavelength: 300 to 400 nm;
black panel temperature: 63°C;
filter: quartz glass (inner)/#275 filter (outer); and
radiation duration: 100 hours.
[0120]
With respect to each laminate glass produced in the
respective Examples and Comparative Examples, similarly,
the visible light transmittance in a wavelength region of
380 to 780 nm was measured in accordance with JIS Z 8722
and JIS R 3106 (1998) by using a recording
spectrophotometer (manufactured by Shimadzu Corporation, U

4000) . Also, the measurement was also carried out in the
same manner after the following S-UV (Super-UV) radiation
test and ATv was calculated by comparison with the
measurement result before radiation according to the
following equation (2). The results are shown in Table 3.
Further, measurement was carried out so that the first
layer in the light incident side is set to be a UV-
shielding layer.
[0121]
ATv = Tv (after S-UV radiation) - Tv (before S-UV
radiation) (2)
[0122]
Super UV (SUV) radiation test
Each radiation sample of 5 x 10 cm was produced and
subjected to the SUV radiation test under the following
conditions:
testing apparatus: EYE Super-UV tester (SUV-F11 model,
manufactured by Iwasaki Electric Co., Ltd.);
UV intensity: 100 mW/m2;
limited wavelength: 295 to 450 nm;
black panel temperature: 63°C;
radiation duration: 300 hours.
[0123]
[Table 1]





[0126]
As shown in Table 1 to Table 3, the heat-shielding
layers produced in the respective Examples and Comparative
Examples all had an electromagnetic wave shielding property
of 10 dB or lower, a haze of 1.0% or lower, a visible light
transmittance of 70% or higher, and a solar radiation
transmittance of 85% or lower of the visible light
transmittance, and the UV-shielding interlayer films

produced in the respective Examples had UV transmittance of
30% or lower.
The laminate glasses according to Examples were found
having ATv, which was calculated from the visible light
transmittance values before and after the weathering-
resistance test, closer to 0 than ATv of the laminate
glasses according to Comparative Examples, which was
calculated from the visible light transmittance values
before and after the weathering-resistance test and.it
implies the laminate glass plates according to Examples
were excellent in weathering-resistance.
INDUSTRIAL APPLICABILITY OF THE INVENTION
[0127]
The present invention provided an interlayer film for
a laminate glass which is excellent in transparency, heat-
shielding property, and electromagnetic wave transmittance
in the case of use for a laminate glass and is not
deteriorated in the visible light transmittance and the
initial optical properties even after a durability test to
light and provide a laminate glass comprising the
interlayer film for a laminate glass.


WE CLAIM:
1. An interlayer film for a laminate glass,
which comprises at least each one layer of a heat-shielding
layer and an UV-shielding layer;
wherein the heat-shielding layer has an electromagnetic wave
shield capability of 10 dB or lower at a frequency of 0.1 MHz to 26.5
GHz; a haze of 1.0% or lower; a visible light transmittance of 70% or
higher; and a solar radiation transmittance of 85% or lower of the
visible light transmittance in a wavelength range of 300 to 2,100 nm
in the case where the heat-shielding layer is inserted between two
plates of glass selected from a group consisting of clear glass,
green glass, high heat ray absorption glass and UV absorption glass
to obtain a laminate glass, and wherein
the UV-shielding layer has an UV transmittance of 35.2% or lower
measured in accordance with SAE J17 96 in the case where the UV-
shielding layer is inserted between two plates of glass selected from
a group consisting of clear glass, green glass, high heat ray
absorption glass, and UV absorption glass to obtain a laminate glass.
2. The interlayer film for a laminate glass as claimed in Claim 1,
which comprises three layers composed of at least the heat-shielding
layer and the UV-shielding layers formed on both faces of the heat-
shielding layer.
3. The interlayer film for a laminate glass as claimed in Claim 2,
wherein the heat-shielding layer contains a transparent resin and a
heat-shielding agent.
4. The interlayer film for a laminate glass as claimed in claim 2,
wherein the heat-shielding layer contains 100 parts by weight of a


polyvinyl acetal resin, 20 to 60 parts by weight of a plasticizer,
0.0001 to 1.0 part by weight of an alkali metal salt and/or alkaline
earth metal salt, 0.1 to 3.0 parts by weight of a tin-dope indium
oxide fine particle, 0.01 to 5.0 parts by weight of a dispersion
stabilizer, and 0.01 to 5.0 parts by weight of an antioxidant,
the tin-dope indium oxide fine particle having an average
particle diameter of 80 nm or smaller and being dispersed so as to
adjust the number of the particle with 100 nm or larger particle
diameter to be 1 or less per 1 µm2.
5. The interlayer film for a laminate glass as claimed in Claim 1,
wherein the heat-shielding layer contains a transparent resin and a
heat-shielding agent.
6. The interlayer film for a laminate glass as claimed in claim 1,
wherein the heat-shielding layer contains 100 parts by weight of a
polyvinyl acetal resin, 20 to 60 parts by weight of a plasticizer,
0.0001 to 1.0 part by weight of an alkali metal salt and/or alkaline
earth metal salt, 0.1 to 3.0 parts by weight of a tin-dope indium
oxide fine particle, 0.01 to 5.0 parts by weight of a dispersion
stabilizer, and 0.01 to 5.0 parts by weight of an antioxidant,
the tin-dope indium oxide fine particle having an average
particle diameter of 80 nm or smaller and being dispersed so as to
adjust the number of the particle with 100 nm or larger particle
diameter to be 1 or less per 1 µm2.
7. The interlayer film for a laminate glass as claimed in Claim 1,
wherein the UV-shielding layer contains a transparent resin and an
UV-cutting agent.


8. The interlayer film for a laminate glass as claimed in Claim
7, wherein the UV-cutting agent is at least one kind of UV absorbents
selected from a group consisting of metal, metal oxide,
benzotriazole, benzophenone, triazine, benzoate, malonic acid ester,
and oxalic acid anilide.
9. The interlayer film for a laminate glass as claimed in Claim 7,
wherein the UV-cutting agent is a metal oxide UV absorbent.
10. The interlayer film for a laminate glass as claimed in Claim 9,
wherein the metal oxide UV absorbent is zinc oxide and/or titanium
oxide.
11. The interlayer film for a laminate glass as claimed in Claim 9,
wherein the metal oxide UV absorbent is coated with an insulating
metal oxide on the surface.
12. The interlayer film for a laminate glass as claimed in Claim 11,
wherein the insulating metal oxide is silica.
13. The interlayer film for a laminate glass as claimed in Claim 9,
wherein the metal oxide UV absorbent is coated with a hydrolyzable
organic silicon compound on the surface.
14. The interlayer film for a laminate glass as claimed in Claim 9,
wherein the metal oxide UV absorbent is coated with a silicone
compound on the surface.
15. The interlayer film for a laminate glass as claimed in Claim 1,
wherein a visible light transmittance decrease is 1.0% or lower

measured in accordance with JIS Z 8722 and JIS R 3106 (1998) after
the interlayer film is inserted between two plates of glass selected
from a group consisting of clear glass, green glass, high heat ray
absorption glass, and UV absorption glass to obtain a laminate glass;
and Super Xenon 100-hours radiation test is run for the laminate
glass.
16. The interlayer film for a laminate glass as claimed in Claim 1,
wherein a visible light transmittance decrease is 3.0% or lower
measured in accordance with JIS Z 8722 and JIS R 3106 (1998) after
the interlayer film is inserted between two plates of glasses
selected from a group consisting of clear glass, green glass, high
heat ray absorption glass, and UV absorption glass to obtain a
laminate glass; and Super UV 300-hours radiation test is run for the
laminate glass.
17. A laminate glass,
which is obtainable by using the interlayer film for the
laminate glass as claimed in Claim 1.

Documents:

01414-kolnp-2006 abstract.pdf

01414-kolnp-2006 assignment-1.1.pdf

01414-kolnp-2006 assignment.pdf

01414-kolnp-2006 claims.pdf

01414-kolnp-2006 correspondence others-1.1.pdf

01414-kolnp-2006 correspondence others.pdf

01414-kolnp-2006 description (complete).pdf

01414-kolnp-2006 form-1.pdf

01414-kolnp-2006 form-3.pdf

01414-kolnp-2006 form-5.pdf

01414-kolnp-2006 international publication.pdf

01414-kolnp-2006 international search report.pdf

01414-kolnp-2006 pct form.pdf

01414-kolnp-2006 priority document.pdf

01414-kolnp-2006-correspondence-1.2.pdf

01414-kolnp-2006-form-18.pdf

1414-KOLNP-2006-ABSTRACT 1.1.pdf

1414-KOLNP-2006-AMANDED PAGES OF SPECIFICATION.pdf

1414-kolnp-2006-assignment.pdf

1414-KOLNP-2006-CLAIMS.pdf

1414-KOLNP-2006-CORRESPONDENCE 1.1.pdf

1414-KOLNP-2006-CORRESPONDENCE.pdf

1414-kolnp-2006-correspondence1.2.pdf

1414-KOLNP-2006-DESCRIPTION (COMPLETE) 1.1.pdf

1414-kolnp-2006-examination report.pdf

1414-KOLNP-2006-FORM 1 1.1.pdf

1414-KOLNP-2006-FORM 13.pdf

1414-kolnp-2006-form 18.pdf

1414-KOLNP-2006-FORM 2.pdf

1414-KOLNP-2006-FORM 3 1.1.pdf

1414-kolnp-2006-form 3.pdf

1414-kolnp-2006-form 5.pdf

1414-KOLNP-2006-FORM-27-1.pdf

1414-KOLNP-2006-FORM-27.pdf

1414-kolnp-2006-gpa.pdf

1414-kolnp-2006-granted-abstract.pdf

1414-kolnp-2006-granted-claims.pdf

1414-kolnp-2006-granted-description (complete).pdf

1414-kolnp-2006-granted-form 1.pdf

1414-kolnp-2006-granted-form 2.pdf

1414-kolnp-2006-granted-specification.pdf

1414-KOLNP-2006-OTHERS.pdf

1414-KOLNP-2006-PRTITION UNDER RULE 137.pdf

1414-kolnp-2006-reply to examination report.pdf

1414-KOLNP-2006-TRANSLATED COPY OF PRIORITY DOCUMENT.pdf


Patent Number 250005
Indian Patent Application Number 1414/KOLNP/2006
PG Journal Number 48/2011
Publication Date 02-Dec-2011
Grant Date 28-Nov-2011
Date of Filing 25-May-2006
Name of Patentee SEKISUI CHEMICAL CO., LTD.
Applicant Address 4-4, NISHITEMMA, 2-CHOME, KITA-KU, OSAKA-SHI, OSAKA 5308565, JAPAN
Inventors:
# Inventor's Name Inventor's Address
1 FUKATANI JUICHI C/O SEKISUI CHEMICAL CO., LTD. 1259, IZUMI, MINAKUCHI-CHO, KOKA-SHI, SHIGA 5288585, JAPAN
2 HATTA, BUNGO C/O SEKISUI CHEMICAL CO., LTD. 1259, IZUMI, MINAKUCHI-CHO, KOKA-SHI, SHIGA 5288585, JAPAN
PCT International Classification Number B32B 17/10
PCT International Application Number PCT/JP2004/018663
PCT International Filing date 2004-12-14
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2003-432891 2003-12-26 Japan