JP2001048601A - Intermediate film for sandwich glass and sandwich glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare an intermediate film for sandwich glass suitable for obtaining the sandwich glass which stably exhibits sound insulation performance excellent in a wide temperature range and is excellent in the basic performance necessary as the sandwich glass, such as transparency, weatherability, penetration resistance, impact energy absorptivity and adequate adhesive power and the sandwich glass formed by using this intermediate film. SOLUTION: This intermediate film for the sandwich glass is an alternate laminate of a resin layer (A) consisting of a polyvinyl acetal resin and a plasticizer and a resin layer (B) consisting of a polyvinyl acetal resin and a plasticizer, in which the resin layer of at least either of the resin layer (A) or the resin layer (B) consists of a polyvinyl acetal resin having the degree of acetalization of 60 to 85 mol%, the acetyl base amount of 8 to 30 mol% and the total of the degree of acetalization and the acetyl base amount of >=75% and a plasticizer and the cloud point of the solution mixture composed of the polyvinyl acetal resin and the plasticizer is <=50 deg.C. The sandwich glass is constituted by interposing the intermediate film for the sandwich glass described above between at least a pair of glass and integrating them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interlayer for laminated glass and a laminated glass using the interlayer.

[0002]

2. Description of the Related Art At least one pair of glass plates is bonded with an interlayer film for laminated glass formed by forming a transparent and flexible resin such as polyvinyl acetal resin plasticized by adding a plasticizer. Laminated glass is excellent in safety because fragments are not scattered at the time of breakage, and thus is widely used, for example, as a window glass of a traffic vehicle such as an automobile or a window glass of a building.

[0003] Among such interlayer films for laminated glass, an interlayer film for laminated glass formed by forming a polyvinyl butyral resin plasticized by adding a plasticizer has an appropriate adhesive strength to glass and a high toughness. Because it has various properties such as tensile strength and excellent transparency, it is particularly suitable for use in window glasses of traffic vehicles, but on the other hand, interlayer films for ordinary polyvinyl butyral resin-based laminated glass are used for building. However, there is a problem that sound insulation is not sufficient for window glasses.

[0004] Generally, sound insulation performance is shown as a transmission loss corresponding to a change in frequency, as shown in FIG.
According to JIS A-4706 "sash", the transmission loss is 500 Hz as shown by a solid line in FIG.
Each of the above-mentioned regions is defined as a constant value according to the sound insulation class.

[0005] Incidentally, the sound insulation performance of a glass plate is remarkably reduced due to the coincidence effect in a frequency region centered at 2000 Hz, as shown by a broken line in FIG. That is, the valley portion of the broken line in FIG. 1 corresponds to a decrease in the sound insulation performance due to the coincidence effect, and indicates that the predetermined sound insulation performance is not maintained.

The coincidence effect means that when a sound wave enters a glass plate, a transverse wave propagates on the glass surface due to the rigidity and inertia of the glass plate, and the transverse wave and the incident sound resonate. Say what happens.

[0007] The conventional laminated glass is extremely excellent in preventing the fragments from being scattered at the time of breakage. The decline is inevitable, and there is a need to improve this point.

[0008] Further, from the equal loudness curve, the human auditory sense has a frequency of 1000 to 60 as compared with other frequency regions.
It is known that the sensitivity in the region of 00 Hz is very high, and it can be said that prevention of a decrease in sound insulation performance due to a coincidence effect is extremely important for improvement in sound insulation (sound insulation) of window glass, walls, and the like. .

The problem with respect to the deterioration of the sound insulation performance due to the coincidence effect is that a minimum portion of the transmission loss in FIG. 1 caused by the coincidence effect (hereinafter, “transmission loss (dB) of the minimum portion” is referred to as “TL value”). In order to improve the sound insulation performance, it is necessary to alleviate the coincidence effect and prevent the TL value from decreasing.

Conventionally, various measures have been taken as means for preventing a decrease in the TL value, such as increasing the mass of laminated glass, multiplying the glass, subdividing the glass area, and improving the glass plate supporting means. However, none of these measures has a sufficient effect of preventing a sufficient decrease in the TL value and has a problem that the cost is not practical.

On the other hand, the demand for sound insulation performance has been increasing more and more recently. For example, in the case of a window glass for a building, it is required to exhibit excellent sound insulation performance at around normal temperature.
That is, it is obtained by plotting the TL value against the temperature.
Temperature at which sound insulation performance is the best 最大 Maximum sound insulation performance temperature (T
Lmax temperature) is around room temperature, and the maximum value of the sound insulation performance {the maximum value of the sound insulation performance (TLmax value)} itself is large.

A similar situation exists in the case of a window glass for a traffic vehicle. For example, there is an increasing demand for high sound insulation performance against wind noise during high-speed running, vibration noise from an engine unit, and the like.

When actually used, these laminated glasses are exposed to a wide range of environmental temperature changes from a low temperature range to a high temperature range. That is, it is required to exhibit excellent sound insulation performance not only near normal temperature but also in a wide temperature range from low temperature to high temperature. However, in the case of a laminated glass using a plasticized polyvinyl butyral resin film, which is the most common conventional interlayer film for laminated glass, the maximum temperature of sound insulation performance (TL)
(max temperature) is higher than room temperature, and there is a problem that sound insulation performance around room temperature is not always good.

Various attempts have been made to address these problems. For example, Japanese Patent Application Laid-Open No. 229742/1990 discloses that “layer A containing a polymer as a main component and having a glass transition temperature of 15 ° C. or less is used. A sound insulating laminated glass characterized in that a plasticized polyvinyl acetal film B and a plasticized polyvinyl acetal film B are laminated between glass plates.

However, the sound insulating laminated glass disclosed in the above disclosure has a sound insulation rating of T according to JIS A-4706.
There is a problem that the sound insulation performance exceeding the s-35 grade is not exhibited and the temperature range in which the good sound insulation performance is exhibited is narrow.

JP-A-51-106190 discloses that “two or more resins having different glass transition temperatures are laminated and a metal plate is adhered to one or both sides, or between these two or more resins. A composite metal plate for vibration isolation characterized by providing a metal plate "is disclosed.

However, although the vibration-damping composite metal sheet disclosed in the above disclosure has been found to have improved vibration damping properties over a wide temperature range, it does not require the sound insulation, transparency, and high impact energy absorption required for laminated glass. It does not satisfy the requirements of the properties and the scattering prevention property at the time of glass breakage, and is not used as a laminated glass.

Japanese Patent Application Laid-Open No. 4-254444 discloses a laminated film composed of two types of resin films (A) and (B), wherein the resin film (A) is made of polyvinyl alcohol having 6 to 10 carbon atoms. The resin film (B) comprises a polyvinyl acetal resin obtained by acetalizing with an aldehyde and a plasticizer, and the resin film (B) comprises a polyvinyl acetal resin obtained by acetalizing polyvinyl alcohol with an aldehyde having 1 to 4 carbon atoms and a plasticizer. A characteristic interlayer film for sound insulating laminated glass "is disclosed.

However, the interlayer film for sound insulating laminated glass disclosed in the above disclosure certainly has the effect of improving the sound insulating performance, and the fluctuation of the sound insulating performance due to the temperature change is not large. In view of these, these improvements are not yet satisfactory.

As described above, an interlayer film for a laminated glass suitable for obtaining a laminated glass having excellent basic performance required as a laminated glass and exhibiting excellent sound insulation performance stably over a wide temperature range over a long period of time is still in practical use. It has not been done yet.

[0021]

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to stably exhibit excellent sound insulation performance in a wide temperature range from a low temperature to a high temperature over a long period of time, and to provide transparency and weather resistance. Provide interlayer film for laminated glass suitable for obtaining laminated glass having excellent basic performance required as laminated glass such as penetration resistance, impact energy absorption, appropriate adhesive strength, etc., and laminated glass using the interlayer film Is to do.

[0022]

In the interlayer film for laminated glass of the present invention, in order to improve the sound insulation performance of the laminated glass in a wide temperature range, a resin layer (A) comprising a polyvinyl acetal resin and a plasticizer is used. And a resin layer (B) composed of a polyvinyl acetal resin and a plasticizer are alternately laminated.

By alternately laminating the resin layer (A) and the resin layer (B), the temperature dependence of the sound insulation performance of the resin layer (A) and the temperature dependence of the sound insulation performance of the resin layer (B) are reduced. The laminated glass produced using the laminated film (intermediate film for laminated glass) obtained by the lamination can exhibit excellent sound insulation performance in a wide temperature range.

Generally, in order to improve the sound insulation performance on the lower temperature side by the laminated film, a method of shifting the sound insulation performance of one resin layer constituting the laminated film to the lower temperature side is adopted. Specifically, it is a method of increasing the amount of plasticizer added in one resin layer to lower the glass transition temperature (Tg) of the resin layer.

However, in the case of the above method, the glass transition temperature of the resin layer is not sufficiently lowered due to poor compatibility between the resin and the plasticizer depending on the type of the resin and the plasticizer used for the resin layer constituting the laminated film. Sometimes. In addition, if the amount of the plasticizer is increased, the glass transition temperature of the resin layer generally decreases, but on the other hand, the long-term durability and weather resistance of the laminated film may be impaired.

The present inventors have conducted intensive studies on the types of resins and plasticizers used in the resin layer constituting the laminated film and on the compatibility thereof, and as a result, as a resin used in the resin layer, a specific acetalization degree and acetyl group content were determined. It has been found that the above problems can be solved by using a polyvinyl acetal resin having the following formula and controlling the compatibility between this resin and a plasticizer, and have completed the present invention.

That is, the interlayer film for laminated glass according to the first aspect comprises a resin layer (A) comprising a polyvinyl acetal resin and a plasticizer and a resin layer (B) comprising a polyvinyl acetal resin and a plasticizer. In the alternate laminate, one of the resin layers (A) and (B) has an acetalization degree of 60 to 85 mol% and an acetyl group content of 8
A polyvinyl acetal resin and a plasticizer having a total of 75 mol% or more and an acetalization degree and an acetyl group content of at least 30 mol%, and the cloud point of the mixed solution of the polyvinyl acetal resin and the plasticizer is 50 C. or lower.

Further, the interlayer film for laminated glass according to claim 2 is the same as the interlayer film for laminated glass according to claim 1, wherein either the resin layer (A) or the resin layer (B) is used. Comprises a polyvinyl acetal resin having a degree of acetalization of 63 to 70 mol%, an amount of acetyl groups of 10 to 24 mol%, and a total of the degree of acetalization and the amount of acetyl groups of 75 mol% or more, and a plasticizer, and Cloud point of mixed solution of polyvinyl acetal resin and plasticizer is 20 ° C
It is characterized by the following.

Further, the interlayer film for laminated glass according to claim 3 is the interlayer film for laminated glass according to claim 1 or 2, wherein the polyvinyl acetal resin is a polyvinyl butyral resin, The agent is triethylene glycol di-2-ethyl butyrate (3G
H), at least one selected from the group consisting of triethylene glycol di-2-ethylhexanoate (3GO) and triethylene glycol di-n-heptanoate (3G7).

A laminated glass according to a fourth aspect is characterized in that the interlayer film for a laminated glass according to any one of the first to third aspects is interposed between at least a pair of glasses and is integrated. And

The method for preparing the polyvinyl acetal resin used for the resin layer (A) and the resin layer (B) constituting the interlayer film for laminated glass of the present invention (hereinafter simply referred to as “interlayer film”) includes, for example, Polyvinyl alcohol (PV
A) is obtained by dissolving an aqueous solution of A) in warm water at a predetermined temperature (for example,
95 ° C), an aldehyde and an acid catalyst were added, the acetalization reaction was allowed to proceed with stirring, and then the reaction was completed by raising the reaction temperature and aging, followed by neutralization, washing with water and Drying is performed to obtain a polyvinyl acetal resin.

The PVA used for preparing the polyvinyl acetal resin is not particularly limited, but preferably has an average degree of polymerization of 500 to 5,000, more preferably 1,000 to 3,000. When the average degree of polymerization of PVA is less than 500, the strength of the resin layer and the interlayer is too weak, and the penetration resistance and impact energy absorption when the laminated glass is formed may be insufficient. PVA
If the average degree of polymerization exceeds 5,000, molding of the resin layer may be difficult, and the strength of the resin layer and the interlayer may be too strong, and the penetration resistance and impact energy absorption when laminated glass may be obtained. May be insufficient.

As the aldehyde used for preparing the polyvinyl acetal resin, for example, formaldehyde,
Examples include acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, valeraldehyde, n-hexylaldehyde, 2-ethylbutyraldehyde, benzaldehyde, cinnamaldehyde and the like.

The various polyvinyl acetal resins thus obtained may be used alone or in combination of two or more. Among them, polyvinyl formal resins obtained by reacting PVA with formaldehyde, P
Narrowly-defined polyvinyl acetal resin obtained by reacting VA with acetaldehyde, polyvinyl butyral resin (PVB) obtained by reacting PVA with n-butyraldehyde, and the like are preferably used, and particularly preferably used. Is PVB. By using PVB as the polyvinyl acetal resin, the transparency, weather resistance, adhesive strength to glass, and the like of the resin layer and the interlayer become more excellent.

In the present invention, the degree of acetalization of the polyvinyl acetal resin used for either the resin layer (A) or the resin layer (B) must be 60 to 85 mol%. Preferably it is 63 to 70 mol%.

If the degree of acetalization of the polyvinyl acetal resin is less than 60 mol%, the compatibility with the plasticizer described later becomes insufficient, and the glass transition temperature of the resin layer does not sufficiently decrease. Sound insulation performance on the low temperature side is not sufficiently improved. Conversely, it is not suitable to obtain a polyvinyl acetal resin having a degree of acetalization of more than 85 mol% because of its difficult reaction mechanism.

In the present invention, the polyvinyl acetal resin used in either the resin layer (A) or the resin layer (B) has an acetyl group content of 8 to 3%.
0 mol%, preferably 10 to 2 mol%.
4 mol%.

When the amount of the acetyl group in the polyvinyl acetal resin is less than 8 mol%, the compatibility with the plasticizer described later becomes insufficient, and the glass transition temperature of the resin layer does not sufficiently decrease. Sound insulation performance on the low temperature side is not sufficiently improved. Conversely, it is not suitable to obtain a polyvinyl acetal resin having an acetyl group content of more than 30 mol% since the reaction rate between PVA and aldehyde is remarkably reduced.

Further, in the present invention, the resin layer (A)
Alternatively, the total of the degree of acetalization and the amount of acetyl groups of the polyvinyl acetal resin used in either one of the resin layers (B) must be 75 mol% or more.

If the total of the degree of acetalization and the amount of acetyl groups of the polyvinyl acetal resin is less than 75 mol%, the compatibility with the plasticizer described below becomes insufficient, and the glass transition temperature of the resin layer becomes low. Therefore, the sound insulation performance on the low temperature side is not sufficiently improved.

When the polyvinyl acetal resin is a polyvinyl butyral resin, the degree of acetalization (degree of butyralization) and the amount of acetyl groups are determined according to JIS K-6728.
"Polyvinyl butyral test method" and nuclear magnetic resonance method (N
(MR).

When the polyvinyl acetal resin is a polyvinyl acetal resin other than the polyvinyl butyral resin, the degree of acetalization is determined according to JIS K-672.
8 or the nuclear magnetic resonance method, the amount of the acetyl group and the amount of vinyl alcohol are measured, and the amount can be calculated by subtracting the amounts of both components from 100.

The other resin layer alternately laminated with either the resin layer (A) or the resin layer (B) is
Rather than sound insulation performance, it functions to improve the mechanical properties and handleability required for the interlayer.

Accordingly, the polyvinyl acetal resin used for the other resin layer is not particularly limited, but preferably has an acetalization degree of 50 mol% or more, and has an acetyl group content of 4 mol%. The following is preferred.

If the degree of acetalization of the polyvinyl acetal resin used for the other resin layer is less than 50 mol%, the compatibility with the plasticizer described below becomes insufficient, and the necessary resistance to the laminated glass is reduced. In some cases, it may be difficult to add a sufficient amount of a plasticizer to impart penetration or impact energy absorption.

When the acetyl group content of the polyvinyl acetal resin used for the other resin layer exceeds 4 mol%, the above-mentioned resin layer used for either the resin layer (A) or the resin layer (B) is used. Since the difference from the acetyl group content of the polyvinyl acetal resin becomes small, the sound insulation performance on the low temperature side may not be sufficiently improved.

The plasticizer used for the resin layer (A) and the resin layer (B) constituting the intermediate film of the present invention includes, for example,
Examples include ester plasticizers such as monobasic acid ester and polybasic acid ester, and phosphoric acid plasticizers such as organic phosphoric acid and organic phosphorous acid.

Examples of the monobasic ester plasticizer include glycols such as triethylene glycol, tripropylene glycol and tetraethylene glycol and butyric acid;
Isobutyric acid, caproic acid, 2-ethylbutyric acid, heptanoic acid,
Glycol-based esters obtained by reaction with an organic acid such as 2-ethylhexylic acid, and the like.

Examples of the polybasic acid ester-based plasticizer include esters obtained by reacting a linear or branched alcohol having 4 to 8 carbon atoms with an organic acid such as adipic acid, sebacic acid and azelaic acid. Is mentioned.

Examples of the phosphoric acid plasticizer include tributoxyethyl phosphate, isodecylphenyl phosphate and the like.

Among the above various plasticizers, for example, triethylene glycol di-2-ethyl butyrate (3G
H), triethylene glycol di-2-ethylhexanoate (3GO), triethylene glycol di-n-heptanoate (3G7), triethylene glycol dicaprylate, triethylene glycol di-n-octoate,
Tetraethylene glycol di-2-ethyl butyrate, tetraethylene glycol di-n-heptanoate, dihexyl adipate, dibenzyl phthalate and the like are preferably used, and 3GH and 3G are particularly preferably used.
O, 3G7 and the like.

The above plasticizers may be used alone or in combination of two or more. Further, the plasticizer used for the resin layer (A) and the plasticizer used for the resin layer (B) may be the same or different.

The amount of the plasticizer to be added to the polyvinyl acetal resin is not particularly limited.
It is preferable that the plasticizer is 30 to 70 parts by weight based on 100 parts by weight of the polyvinyl acetal resin.

If the amount of the plasticizer added is less than 30 parts by weight based on 100 parts by weight of the polyvinyl acetal resin, the plasticization of the polyvinyl acetal resin may be insufficient. In addition, the mechanical properties of the interlayer and the adhesive strength to glass may be insufficient.

Among the combinations of the polyvinyl acetal resin and the plasticizer, polyvinyl butyral resin is used as the polyvinyl acetal resin, and 3
A combination using at least one selected from the group consisting of GH, 3GO and 3G7 is particularly preferred.

The interlayer composed of the resin layer (A) and the resin layer (B) according to the above-mentioned combination has not only a sound insulation performance but also transparency, weather resistance, penetration resistance, impact energy absorption, and the interlayer between the glass and the interlayer. It is suitable for obtaining laminated glass that is even more excellent in basic performance such as proper adhesive strength.

In the present invention, the cloud point of the mixed solution of the polyvinyl acetal resin and the plasticizer used for either the resin layer (A) or the resin layer (B) is 50 ° C. or less. The temperature is preferably 30 ° C. or lower, and particularly preferably 20 ° C. or lower.

The cloud point referred to in the present invention is defined by JIS K-2
269 is a cloud point measured according to “Pour point of crude oil and petroleum products and cloud point test method of petroleum products”. Specifically, 8 parts by weight of polyvinyl acetal resin was dissolved in 100 parts by weight of plasticizer. When the mixed solution is heated to 150 ° C. or more and then left in an atmosphere of 10 ° C. to 30 ° C. to lower the temperature, it means a temperature at which clouding starts to occur in a part of the mixed solution. It can be said that the lower the cloud point, the better the compatibility between the polyvinyl acetal resin and the plasticizer.

As a method of measuring the cloud point, for example,
A method of visually observing the appearance of the mixed solution, a method of measuring the haze value of the mixed solution with a haze meter, and preparing a multi-step limit sample for the degree of haze in advance, and judging the haze by comparing with the limit sample And the like.

The above cloud point indicates the compatibility between the polyvinyl acetal resin and the plasticizer. Therefore, the cloud point should be 50 ° C
By doing so, the compatibility between the polyvinyl acetal resin used for either the resin layer (A) or the resin layer (B) and the plasticizer becomes extremely excellent.

As a result, the glass transition temperature of the one resin layer is effectively lowered, so that the sound insulation performance on the low temperature side of the resin layer is significantly improved. In addition, since the transfer of the plasticizer to the other resin layer adjacent when the intermediate film is formed is effectively suppressed, a laminated glass exhibiting stable performance for a long period of time can be obtained.

The mixed solution of the polyvinyl acetal resin and the plasticizer used for the one resin layer has a cloud point of 50 ° C.
If it exceeds 300, the effect of improving the sound insulation performance on the low temperature side and the effect of stabilizing the performance of the laminated glass for a long period of time may not be sufficiently obtained.

The cloud point of the mixed solution of the polyvinyl acetal resin and the plasticizer used for the other resin layer alternately laminated with the one resin layer is not particularly limited. Preferably, there is.

The cloud point of the mixed solution of the polyvinyl acetal resin and the plasticizer used for the other resin layer is 120.
If the temperature exceeds ℃, the compatibility between the polyvinyl acetal resin and the plasticizer becomes insufficient, and the mechanical properties of the laminated glass may decrease.

In the resin layer (A) and / or the resin layer (B) constituting the intermediate film of the present invention, if necessary, other than the polyvinyl acetal resin and the plasticizer, as long as the achievement of the object of the present invention is not hindered. One or more of various additives such as an ultraviolet absorber, a light stabilizer, an antioxidant, an adhesion modifier, a surfactant, and a coloring agent may be added to the composition.

The intermediate film of the present invention needs to be an alternate laminate of the resin layer (A) and the resin layer (B). In the alternate laminate, for example, the resin layer (B) is A resin layer in which the degree of acetalization of the polyvinyl acetal resin, the amount of the acetyl group and the sum of the degree of acetalization and the amount of the acetyl group are specified, and the cloud point of the mixed solution of the polyvinyl acetal resin and the plasticizer is specified. In this case, it is preferable that the resin layer (A) be an outer layer, that is, a contact layer with glass, and the resin layer (B) be an inner layer, that is, a non-contact layer with glass.

By using the resin layer (A) as the outer layer, the handleability of the interlayer film and the mechanical properties of the laminated glass can be improved. Conversely, if the resin layer (B) is an outer layer, the flexibility of the resin layer (B) may deteriorate the handleability of the interlayer film.

The structure of the alternate laminate is not particularly limited. For example, a three-layer laminate composed of a resin layer (A) / resin layer (B) / resin layer (A) or a resin layer (A) / resin layer (B) / resin layer (A) / resin layer (B) /
A five-layer laminate composed of the resin layer (A) is preferred.

The thickness of the intermediate film of the present invention is not particularly limited, but is 0.3 to 1.6 m as in the case of a normal intermediate film.
m is preferable. The sound insulation performance itself becomes more excellent as the thickness of the interlayer becomes thicker.However, if the thickness of the interlayer becomes too thick, the penetration resistance and impact energy absorption when laminated glass may be reduced. Preferably, the thickness is in the range.

Examples of the method for producing an interlayer film according to the present invention include a method in which a resin layer (A) and a resin layer (B) are separately formed (formed into a film) and then alternately laminated, A method of integrally forming (integrally forming a film) such that the resin layer (A) and the resin layer (B) are alternately laminated by using a molding machine is exemplified.

Next, the laminated glass of the present invention is manufactured by interposing the above-mentioned interlayer film of the present invention between at least a pair of glasses and integrating them.

The above glass includes not only ordinary inorganic transparent glass but also organic transparent glass such as a polycarbonate plate and a polymethyl methacrylate plate.

The type of the above glass is not particularly limited. For example, float glass, polished glass, flat glass, curved glass, side-by-side glass, template glass, wire mesh-type glass, colored glass, etc. Various inorganic glasses and organic glasses are mentioned, and one or more of these are suitably used. The thickness of the glass is not particularly limited as long as it can be appropriately selected depending on the application and purpose.

The method for producing the laminated glass is not particularly limited, and the same production method as that for ordinary laminated glass is employed. For example, the intermediate film of the present invention is sandwiched between two transparent glass plates, put in a rubber bag, and preliminarily bonded at a temperature of about 70 to 110 ° C. while suctioning and degassing under reduced pressure. Using a temperature of about 120 to 150 ° C and a pressure of 10 to 15 kg /
A desired laminated glass can be obtained by performing main bonding by heating and pressing under conditions of about cm ² .

[0075]

The intermediate film of the present invention comprises a resin layer (A) composed of a polyvinyl acetal resin and a plasticizer, and a resin layer (B) composed of a polyvinyl acetal resin and a plasticizer, which are alternately laminated. Either the resin layer (A) or the resin layer (B) is formed from a polyvinyl acetal resin having a specific acetalization degree, an acetyl group amount and a total of the acetalization degree and the acetyl group amount, and a plasticizer. Become
In addition, since the cloud point of the mixed solution of the polyvinyl acetal resin and the plasticizer is set to be equal to or less than a specific value, excellent sound insulation performance is stably exhibited over a long temperature range from low to high temperatures over a long period of time. In addition, it is suitable for obtaining laminated glass having excellent basic performances such as transparency, weather resistance, penetration resistance, impact energy absorption, and appropriate adhesive strength.

A polyvinyl butyral resin was used as the polyvinyl acetal resin, and 3GH was used as the plasticizer.
By using at least one selected from the group consisting of 3GO and 3G7, the above performance can be further improved.

Since the laminated glass of the present invention is produced by using the above-mentioned interlayer film of the present invention, it exhibits excellent sound insulation performance over a wide temperature range from a low temperature to a high temperature in a stable manner for a long period of time. Excellent in basic performance such as weather resistance, penetration resistance, impact energy absorption, and appropriate adhesive strength.

[0078]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” means “parts by weight”.

(Example 1)

(1) Preparation of Resin Layer (A) As a polyvinyl acetal resin, polyvinyl butyral resin {PVB-a (butyralization degree: 68.9 mol%,
(Acetyl group content: 0.9 mol%) To 100 parts of triethylene glycol di-2-ethylhexanoate (3GO) 39 parts was added as a plasticizer and kneaded sufficiently with a mixing roll. Using a press molding machine,
Press molding was performed at 50 ° C. for 30 minutes to produce a resin layer (A) having a thickness of 0.2 mm.

(2) Preparation of Resin Layer (B) As a polyvinyl acetal resin, polyvinyl butyral resin {PVB-b (butyralization degree: 63.6 mol%,
(Acetyl group content: 13.0 mol%) To 100 parts, 100 parts of 3GO was added as a plasticizer, and the mixture was sufficiently kneaded with a mixing roll.
Press molding was performed at 50 ° C. for 30 minutes to produce a resin layer (B) having a thickness of 0.4 mm.

(3) Measurement of Cloud Point The cloud point of the mixed solution of PVB-b and 3GO used for the resin layer (B) was measured by the following method. Table 1 shows the results.
Was as shown in FIG. [Measurement of Cloud Point] A plastic test tube was charged with 100 parts of a plasticizer and 8 parts of PVB, and heated to 170 ° C. to dissolve PVB in the plasticizer to obtain a PVB-plasticizer solution. Then, the solution was stirred and cooled while measuring the temperature of the solution with a thermocouple, and the temperature at which part of the solution began to become cloudy was read, and this temperature was taken as the cloud point.

(4) Preparation of Intermediate Film and Laminated Glass Using the resin layer (A) and the resin layer (B) obtained above,
The laminated structure is resin layer (A) / resin layer (B) / resin layer (A)
And a three-layer intermediate film was obtained. Next, this intermediate film was placed on two transparent float glasses (length 30 cm ×
It is sandwiched between 30 cm wide and 3 mm thick), placed in a rubber bag, degassed for 20 minutes at a vacuum of 20 torr, and then transferred to a 90 ° C. oven while being degassed.
It was kept at 0 ° C. for 30 minutes, and the laminated glass was preliminarily bonded by a vacuum press.

Next, the pre-bonded laminated glass was put into an autoclave, and the temperature was 135 ° C., the pressure was 12 kg.
/ Cm ² for 20 minutes to produce a transparent laminated glass.

(5) Evaluation The sound insulation of the laminated glass obtained above was evaluated by the following method. The results were as shown in Table 1. [Evaluation method of sound insulation] A specimen was cut out from the laminated glass obtained above, and this specimen was vibrated by a vibration generator (trade name "G21-005D", manufactured by Shinken Co., Ltd.) for a dumping test. The vibration characteristics obtained therefrom are amplified by a mechanical impedance amplifier (trade name “XG-81”, manufactured by Rion), and the vibration spectrum is analyzed by an FFT analyzer (trade name “FFT Spectrum Analyzer HP-3582A”).
A ", manufactured by Yokogawa Hewlett-Packer Company). A graph showing the relationship between the frequency (Hz) and the transmission loss (dB) is created from the thus obtained loss coefficient and the ratio of the resonance frequency to the glass, and the minimum transmission loss ｛TL value (about 2,000 Hz) is obtained. dB)｝ was determined.
The measurement was performed at 0 ° C., 10 ° C., 20 ° C., and 30 ° C., respectively.
0 or more.

(Example 2) The resin layer (A) produced in Example 1 was used as it is as the resin layer (A). Also, except that 60 parts of 3GO was added as a plasticizer to 100 parts of polyvinyl butyral resin (PVB-c (degree of butyralization: 64.5 mol%, acetyl group content: 13.0 mol%)) as a polyvinyl acetal resin. In the same manner as in Example 1, a resin layer (B) having a thickness of 0.4 mm was produced.

Example 3 As a polyvinyl acetal resin, 100 parts of polyvinyl butyral resin {PVB-d (butyralization degree: 65.9 mol%, acetyl group content: 0.9 mol%)} was added to 100 parts of trivinyl chloride as a plasticizer. Except that 40 parts of ethylene glycol di-2-ethyl butyrate (3GH) was added, the same procedure as in Example 1 was repeated to form a film having a film thickness of 0.1.
A 2 mm resin layer (A) was produced. Moreover, PVB-b100 used in Example 1 as a polyvinyl acetal resin was used.
A resin layer (B) having a thickness of 0.4 mm was prepared in the same manner as in Example 1 except that 65 parts of 3GH was added as a plasticizer to the parts.

Example 4 The procedure of Example 1 was repeated, except that 40 parts of triethylene glycol di-n-heptanoate (3G7) was added as a plasticizer to 100 parts of PVB-d used in Example 3 as a polyvinyl acetal resin. In the same manner as in the case, a resin layer (A) having a thickness of 0.1 mm was produced. In addition, 100 parts of PVB-c used in Example 2 as a polyvinyl acetal resin was mixed with 3G7 as a plasticizer.
A resin layer (B) having a thickness of 0.2 mm was produced in the same manner as in Example 1 except that 65 parts were added.

Comparative Example 1 The resin layer (A) prepared in Example 1 was used as it was as the resin layer (A). Also, except that 65 parts of 3GO as a plasticizer was added to 100 parts of polyvinyl butyral resin (PVB-e (butyralization degree: 57.3 mol%, acetyl group content: 13.0 mol%)) as a polyvinyl acetal resin. In the same manner as in Example 1, a resin layer (B) having a thickness of 0.4 mm was produced.

(Comparative Example 2) The resin layer (A) produced in Example 3 was directly used as the resin layer (A). Further, PVB used in Example 3 as a polyvinyl acetal resin was used.
In the same manner as in Example 1 except that 50 parts of 3GH was added as a plasticizer to 100 parts of -d, a film thickness of 0.1 part was used.
A 4 mm resin layer (B) was produced.

Comparative Example 3 The resin layer (A) produced in Example 3 was used as it was as the resin layer (A). Further, PVB used in Example 1 as a polyvinyl acetal resin was used.
In the same manner as in Example 1, except that 40 parts of 3GO was added as a plasticizer to 100 parts of -a.
A 4 mm resin layer (B) was produced.

The cloud point of the mixed solution of each polyvinyl butyral resin and each plasticizer used for each resin layer (B) prepared in Examples 2 to 4 and Comparative Examples 1 to 3 was the same as in Example 1. Was measured respectively. The results were as shown in Table 1.

Using the respective resin layers (A) and (B) prepared in Examples 2 and 3 and Comparative Examples 1 to 3, in the same manner as in Example 1, a three-layer intermediate film and a laminated glass Was prepared. Further, in Example 4, the laminated structure was resin layer (A) / resin layer (B) / resin layer (A) / resin layer (B) /
A five-layer intermediate film was formed by laminating the resin layer (A). A laminated glass was produced in the same manner as in Example 1 except that the above-mentioned intermediate film was used.

The sound insulation performance of the laminated glasses obtained in Examples 2 to 4 and Comparative Examples 1 to 3 was evaluated in the same manner as in Example 1. The results were as shown in Table 1.

[0095]

[Table 1]

As is clear from Table 1, the laminated glasses of Examples 1 to 4 manufactured using the interlayer films of Examples 1 to 4 according to the present invention are all excellent in a wide temperature range of 0 ° C. to 30 ° C. Demonstrated sound insulation performance.

On the other hand, the degree of butyralization of the polyvinyl butyral resin (PVB-e) used for the resin layer (B) is less than 60 mol%, and the total of the degree of butyral and the amount of acetyl group is less than 75 mol%. And the PVB-
Comparative Example 1 prepared using the interlayer of Comparative Example 1 in which the cloud point of the mixed solution of e and the plasticizer (3GO) exceeded 50 ° C.
The laminated glass was poor in sound insulation performance at 0 ° C to 10 ° C.

The polyvinyl butylal resin (PVB-d) used for the resin layer (B) has an acetyl group content of 8 mol%.
Comparative Example in which the total of the butyralization degree and the amount of acetyl group was less than 75 mol%, and the cloud point of the mixed solution of the PVB-d and the plasticizer (3GH) exceeded 50 ° C. The laminated glass of Comparative Example 2 produced using the intermediate film of No. 2 had poor sound insulation performance at 0 ° C. to 20 ° C.

Further, the acetyl group content of the polyvinyl butyral resin (PVB-a) used for the resin layer (B) is less than 8 mol%, and the total of the butyralization degree and the acetyl group content is less than 75 mol%. Also, the laminated glass of Comparative Example 3 produced using the interlayer of Comparative Example 3 in which the cloud point of the mixed solution of PVB-a and the plasticizer (3GO) exceeded 50 ° C was also 0 ° C to 20 ° C. Sound insulation performance was poor.

[0100]

As described above, the interlayer film for laminated glass of the present invention stably exhibits excellent sound insulation performance in a wide temperature range from low to high temperatures over a long period of time, and exhibits transparency and weather resistance. It is suitable for obtaining a laminated glass excellent in basic performance required as a laminated glass such as penetration resistance, impact energy absorption, and proper adhesive strength.

Further, the laminated glass of the present invention using the above-mentioned interlayer film stably exhibits excellent sound insulation performance over a long temperature range from a low temperature to a high temperature over a long period of time, and has the above-mentioned basic performance required as a laminated glass. Therefore, it is suitably used as a sound insulating laminated glass for a window glass of a building, a traffic vehicle, or the like that requires particularly high sound insulating performance.

[0102]

[Brief description of the drawings]

FIG. 1 is a graph showing the sound insulation performance of a laminated glass.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) C08K 5/103 C08K 5/103 C08L 29/14 C08L 29/14 F term (Reference) 4F071 AA30 AC10 AE04 AF58 AH19 BA01 BB03 BB06 BC01 4F100 AG00C AG00D AH00A AH00B AK23A AK23B BA02 BA04 BA08 BA10C BA10D CA04A CA04B GB90 JH01 JK11 JL09 JN01 YY00A YY00B 4G061 AA04 BA02 CA02 CB05 CB18 CC01 CD02 CD02 BE02

Claims (4)

[Claims] 1. An alternating laminate of a resin layer (A) composed of a polyvinyl acetal resin and a plasticizer, and a resin layer (B) composed of a polyvinyl acetal resin and a plasticizer,
The resin layer of either the resin layer (A) or the resin layer (B) has an acetalization degree of 60 to 85 mol%, an acetyl group amount of 8 to 30 mol%, and a total of the acetalization degree and the acetyl group amount. An interlayer film for laminated glass, comprising 75% by mole or more of a polyvinyl acetal resin and a plasticizer, and wherein the mixed solution of the polyvinyl acetal resin and the plasticizer has a cloud point of 50 ° C or less. 2. Either the resin layer (A) or the resin layer (B) has an acetalization degree of 63 to 70 mol%, an acetyl group amount of 10 to 24 mol%, and an acetalization degree and an acetyl group amount. And a total of 75 mol% or more of a polyvinyl acetal resin and a plasticizer, and the mixed solution of the polyvinyl acetal resin and the plasticizer has a cloud point of 20 ° C. or less. The interlayer film for laminated glass according to 1. 3. The polyvinyl acetal resin is a polyvinyl butyral resin, and the plasticizer is selected from the group consisting of triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate and triethylene glycol di-n-heptanoate. The interlayer film for laminated glass according to claim 1, wherein the interlayer film is at least one selected from the group consisting of: 4. The method according to claim 1, wherein at least between the pair of glasses.
A laminated glass comprising the interlayer film for laminated glass according to claim 3 interposed and integrated.