JP4465334B2 - Laminated glass interlayer film and laminated glass - Google Patents

Description

The present invention relates to an interlayer film for laminated glass and laminated glass that does not whiten even when wet and has excellent sound insulation.

Laminated glass is widely used as a window glass for vehicles such as automobiles, aircrafts, buildings, and the like because it is safe because it does not scatter glass fragments even if it is damaged by an external impact. Examples of the laminated glass include those obtained by interposing an interlayer film for laminated glass made of polyvinyl acetal such as polyvinyl butyral plasticized with a plasticizer between at least a pair of glasses.

In recent years, attempts have been made to reduce the thickness of the entire laminated glass due to problems such as weight reduction and cost. However, if the thickness of the entire laminated glass is reduced, there is a problem that heat insulation and sound insulation are lowered. In particular, when such a laminated glass is used as a windshield of an automobile or the like, the sound insulation performance of a sound of about 5000 Hz, which has not been a problem until now, such as wind noise and wiper driving sound has become a problem. Yes.

For such a problem, for example, Patent Document 1 discloses that the sound insulation of the entire laminated glass can be improved by including a large amount of plasticizer in the interlayer film for laminated glass. Yes.

Currently, such laminated glass is mostly used only for windshields in vehicles such as automobiles, but recently, in order to improve crime prevention and sound insulation, laminated glass is also used for vehicle side glass. Use is under consideration.

However, such laminated glass with sound insulation has high hydrophilicity, so there is no problem when the glass periphery is covered with urethane adhesive etc. like the windshield, but the upper part like the side glass. When used on exposed parts, water penetrates into the interlayer film for laminated glass, especially when it rains, causing whitening, and as a result, the interlayer film for laminated glass peels off from the glass. was there. For this reason, there is a need for an interlayer film for laminated glass that has sufficient impact resistance and sound insulation properties and does not cause whitening even when it is used with a partially sectioned surface such as a side glass. Is the current situation.
JP-A-5-310449

An object of this invention is to provide the intermediate film for laminated glasses and laminated glass which do not whiten even if it gets wet with water, and has the outstanding sound insulation.

The present invention is an interlayer film for laminated glass comprising a sound insulating layer and two protective layers sandwiching the sound insulating layer, wherein the sound insulating layer has an acetylation degree of 7 mol% or less and a butyralization degree. The protective layer contains 45 to 75 parts by weight of a plasticizer with respect to 100 parts by weight of 68 to 82 mol% of polyvinyl butyral, and the protective layer has a degree of acetylation of 4 mol% or less, a degree of butyralization of 60 to 75 mol%, and The interlayer film for laminated glass contains 20 to 45 parts by weight of a plasticizer with respect to 100 parts by weight of polyvinyl butyral which is equal to or less than the degree of butyralization of polyvinyl butyral contained in the sound insulation layer.
The present invention is described in detail below.

As a result of intensive studies, the inventors of the present invention have found that an interlayer film for laminated glass using a sound insulating layer and a protective layer in which the degree of acetylation and the degree of butyral are in a certain range, respectively, whitens even when wet. It has been found that it has excellent sound insulation, and the present invention has been completed.
This is because, by limiting to a certain range, a very large amount of plasticizer can be stably contained in the sound insulation layer, so that the hydrophobicity (lipophilicity) of the sound insulation layer is increased, so that the penetration of water can be prevented. It can prevent and whitening can be suppressed. In addition, since a large amount of plasticizer is stably contained, the entire interlayer film for laminated glass can exhibit high sound insulation.

The interlayer film for laminated glass of the present invention comprises a sound insulating layer and two protective layers sandwiching the sound insulating layer.

The sound insulation layer is for imparting sound insulation to the interlayer film for laminated glass of the present invention.
The sound insulation layer contains 45 to 75 parts by weight of a plasticizer with respect to 100 parts by weight of polyvinyl butyral having an acetylation degree of 7 mol% or less and a butyralization degree of 68 to 82 mol%.

The polyvinyl butyral can be prepared by converting polyvinyl alcohol into butyral with butyraldehyde.
The polyvinyl alcohol used as the raw material is usually obtained by saponifying polyvinyl acetate, and the polyvinyl butyral used in the sound insulation layer has a degree of saponification of 7 mol% or less, and thus has a degree of saponification of 93 mol%. The polyvinyl alcohol described above is used, and the polyvinyl butyral used in the protective layer has a degree of acetylation of 4 mol% or less as described later, and therefore a polyvinyl alcohol having a saponification degree of 96 mol% or more is used.
Moreover, the preferable minimum of the polymerization degree of the said polyvinyl alcohol is 200, and a preferable upper limit is 5000. If it is less than 200, the penetration resistance of the resulting laminated glass may be lowered. If it exceeds 5000, the moldability of the layer is deteriorated, and the rigidity of the layer is excessively increased, so that the workability is deteriorated. is there. A more preferred lower limit is 500, and a more preferred upper limit is 4000.

Polyvinyl butyral forming the sound insulation layer has an upper limit of 7 mol% of acetylation degree. If it exceeds 7 mol%, the hydrophobicity becomes low, which causes whitening. A preferred lower limit is 0.5 mol%.

The polyvinyl butyral forming the sound insulation layer has a lower butyralization degree of 68 mol% and an upper limit of 82 mol%.
As a result of diligent studies, the inventors of the present invention have achieved excellent sound insulation by limiting the degree of butyralization of the polyvinyl butyral forming the sound insulation layer to a relatively high range, and the case where the polyvinyl butyral is used for a vehicle side glass or the like. However, the present inventors have found that an interlayer film for laminated glass that hardly causes whitening can be obtained. This is because, by making polyvinyl alcohol highly butyral, a very large amount of plasticizer can be stably contained in the sound insulation layer, so that the hydrophobicity (lipophilicity) of the sound insulation layer is increased, so that water penetration Can be prevented and whitening can be suppressed. In addition, since a large amount of plasticizer is stably contained, the entire interlayer film for laminated glass can exhibit high sound insulation.
If the amount is less than 68 mol%, a sufficient amount of plasticizer cannot be stably contained, so that the hydrophobicity is lowered, causing whitening or bleeding out. Moreover, since a sufficient amount of plasticizer cannot be contained, sufficient sound insulation cannot be obtained. If it exceeds 82 mol%, synthesis may become difficult and productivity may deteriorate. A preferred lower limit is 76 mol%.

The plasticizer is not particularly limited, and examples thereof include organic plasticizers such as monobasic organic acid esters and polybasic organic acid esters; phosphoric acid plasticizers such as organic phosphoric acid and organic phosphorous acid. Is mentioned.

The monobasic organic acid ester plasticizer is not particularly limited, and examples thereof include glycols such as triethylene glycol, tetraethylene glycol, and tripropylene glycol, butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, and heptyl acid. , Glycol esters obtained by reaction with monobasic organic acids such as n-octylic acid, 2-ethylhexylic acid, pelargonic acid (n-nonyl acid), decyl acid and the like. Among them, triethylene glycol-dicaproate, triethylene glycol-di-2-ethylbutyrate, triethylene glycol-di-n-octylate, triethylene glycol-di-2-ethylhexyl ester, etc. Glycol and the like are preferred.

The polybasic organic acid ester plasticizer is not particularly limited. For example, a polybasic organic acid such as adipic acid, sebacic acid or azelaic acid and a linear or branched alcohol having 4 to 8 carbon atoms. Examples include esters. Of these, dibutyl sebacic acid ester, dioctyl azelaic acid ester, dibutyl carbitol adipic acid ester and the like are preferable.

The organophosphate plasticizer is not particularly limited, and examples thereof include tributoxyethyl phosphate, isodecylphenyl phosphate, triisopropyl phosphate, and the like.

Specific examples that are particularly preferably used as the plasticizer include triethylene glycol-di-ethyl butyrate, triethylene glycol-di-2-ethylhexanoate, triethylene glycol-di-butyl sebacate, and the like.

The lower limit of the plasticizer content in the sound insulation layer is 45 parts by weight with respect to 100 parts by weight of the polyvinyl butyral, and the upper limit is 75 parts by weight. If the amount is less than 45 parts by weight, the hydrophobicity of the sound insulation layer is lowered, causing whitening, or not having sufficient sound insulation because the amount of plasticizer is not sufficient, and if exceeding 75 parts by weight, the plasticizer Bleed-out occurs, the transparency and adhesiveness of the interlayer film for laminated glass are lowered, and the optical distortion of the resulting laminated glass is increased. A preferred lower limit is 50 parts by weight and a preferred upper limit is 70 parts by weight.

The thickness of the sound insulation layer is not particularly limited, but a preferable lower limit is 0.05 mm. If the thickness is less than 0.05 mm, sufficient sound insulation may not be obtained. A more preferred lower limit is 0.08 mm. In addition, although an upper limit is not specifically limited, when the thickness as an intermediate film for laminated glasses is considered, a preferable upper limit is 0.5 mm.

The protective layer prevents a large amount of plasticizer contained in the sound insulation layer from bleeding out and lowering the adhesion between the interlayer film for laminated glass and the glass, and is resistant to the resulting interlayer film for laminated glass. It has a role of imparting penetrability.

In the polyvinyl butyral forming the protective layer, the upper limit of the degree of acetylation is 4 mol%. If it exceeds 4 mol%, it may be difficult to ensure sufficient penetration resistance of the laminated glass. A preferred lower limit is 0.5 mol%.

The polyvinyl butyral forming the protective layer has a lower butyralization degree of 60 mol% and an upper limit of 75 mol%. If it is less than 60 mol%, it becomes difficult to contain a plasticizer in an amount necessary for exhibiting sufficient penetration resistance, which causes bleed-out. If it exceeds 75 mol%, the protective layer and glass Adhesive strength with is significantly reduced.
The degree of butyralization of the polyvinyl butyral forming the protective layer is not more than the degree of butyralization of the polyvinyl butyral forming the sound insulation layer. If the degree of butyralization of the polyvinyl butyral that forms the protective layer becomes higher than the degree of butyralization of the polyvinyl butyral that forms the sound insulation layer, a large amount of plasticizer moves from the sound insulation layer to the protection layer, and the sound insulation layer Since the hydrophobicity (lipophilicity) of the water becomes low, water penetration cannot be prevented and whitening cannot be suppressed.

The lower limit of the plasticizer content in the protective layer is 20 parts by weight with respect to 100 parts by weight of the polyvinyl butyral, and the upper limit is 45 parts by weight. When the amount is less than 20 parts by weight, the penetration resistance is lowered. When the amount exceeds 45 parts by weight, the plasticizer bleeds out, and the transparency and adhesiveness of the interlayer film for laminated glass are lowered. The optical distortion becomes large. A preferred lower limit is 32 parts by weight and a preferred upper limit is 36 parts by weight.

As the plasticizer in the protective layer, the same plasticizer as in the above-described sound insulation layer may be used.

Although it does not specifically limit as thickness of the said protective layer, A preferable minimum is 0.2 mm and a preferable upper limit is 0.5 mm. If the thickness is less than 0.2 mm, penetration resistance may not be obtained. If the thickness exceeds 0.5 mm, optical distortion tends to occur in the interlayer film for laminated glass. A more preferable lower limit is 0.3 mm, and a more preferable upper limit is 0.4 mm.

The sound insulation layer and the protective layer may be modified with an antioxidant, a light stabilizer, an adhesive strength modifier, a modified silicone oil, a flame retardant, an antistatic agent, an adhesive strength modifier, a moisture resistant agent, a heat ray reflective agent, or a heat ray, if necessary. You may contain additives, such as an absorber.

The method for producing the sound insulating layer and the protective layer is not particularly limited, and examples thereof include a method in which a plasticizer and an additive to be blended as necessary are added to polyvinyl butyral, kneaded, and molded. . The kneading method is not particularly limited, and examples thereof include a method using an extruder, a plastograph, a kneader, a Banbury mixer, a calendar roll, and the like. Especially, since it is suitable for continuous production, the method using an extruder is suitable.

The method for producing the interlayer film for laminated glass of the present invention is not particularly limited. For example, the sound insulation layer and the protective layer are produced in a sheet form by a usual film forming method such as an extrusion method, a calendering method, or a pressing method. Examples of the method include a method of laminating after film formation.

Laminated glass using the interlayer film for laminated glass of the present invention is also one aspect of the present invention.

It does not specifically limit as a glass plate used for the laminated glass of this invention, The transparent plate glass generally used can be used, For example, float plate glass, polished plate glass, type | mold plate glass, netted glass, wire-containing plate glass, Organic glass, such as colored plate glass and heat ray absorbing glass, may be mentioned.

It does not specifically limit as a manufacturing method of the laminated glass of this invention, A conventionally well-known manufacturing method can be used.

Since the laminated glass of the present invention has an interlayer film for laminated glass constituted by the above method, it does not whiten even when wet with water, and has excellent sound insulation, so it is effectively used for side glass of automobiles, etc. can do.

ADVANTAGE OF THE INVENTION According to this invention, even if it gets wet, it does not whiten and can provide the intermediate film for laminated glasses and laminated glass which have the outstanding sound insulation.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Example 1
(1) Preparation of sound insulation layer Triethylene glycol di-2-ethylhexanoate as a plasticizer with respect to 100 parts by weight of polyvinyl butyral having an average polymerization degree of 3000, an acetylation degree of 1 mol%, and a butyralization degree of 77 mol% (Abbreviation 3GO) 60 parts by weight was added and kneaded sufficiently with a mixing roll, and then press molded at 150 ° C. for 30 minutes using a press molding machine to obtain a sound insulating layer having an average film thickness of 0.1 mm.

(2) Preparation of protective layer Triethylene glycol di-2-ethylhexanoate as a plasticizer with respect to 100 parts by weight of polyvinyl butyral having an average polymerization degree of 1700, an acetylation degree of 1 mol% and a butyralization degree of 68 mol% (Abbreviation 3GO) 40 parts by weight was added and kneaded sufficiently with a mixing roll, and then press molded at 150 ° C. for 30 minutes using a press molding machine to obtain a protective layer having an average film thickness of 0.33 mm.

(3) Production of interlayer film for laminated glass The obtained sound insulation layer was sandwiched between two protective layers and pressed at 150 ° C. for 30 minutes using a press molding machine to obtain an average film thickness of 0.76 mm. An interlayer film for glass was obtained.

(4) Production of laminated glass The obtained interlayer film for laminated glass was sandwiched between transparent float glasses (length 30 cm × width 30 cm × thickness 2.5 mm) and placed in a rubber bag, and the degree of vacuum was 20 torr. After deaeration for 5 minutes, it was transferred to an oven while being deaerated, and further vacuum pressed while being kept at 90 ° C. for 30 minutes. The laminated glass preliminarily pressure-bonded in this manner was pressure-bonded for 20 minutes in an autoclave under conditions of 135 ° C. and a pressure of 1176 kPa to obtain a laminated glass.

(Example 2)
An interlayer film for laminated glass and laminated glass were produced in the same manner as in Example 1 except that polyvinyl butyral having a butyralization degree of 81 mol% was used in producing the sound insulating layer.

(Example 3)
(1) Production of sound insulation layer Triethylene glycol-di-2-ethylhexanoate as a plasticizer with respect to 100 parts by weight of polyvinyl butyral having an average polymerization degree of 3000, an acetylation degree of 7 mol% and a butyralization degree of 76 mol% (Abbreviation 3GO) 65 parts by weight was added and sufficiently kneaded with a mixing roll, and then press molded at 150 ° C. for 30 minutes using a press molding machine to obtain a sound insulation layer having an average film thickness of 0.08 mm.

(2) Preparation of protective layer Triethylene glycol di-2-ethylhexanoate as a plasticizer with respect to 100 parts by weight of polyvinyl butyral having an average polymerization degree of 1700, an acetylation degree of 1 mol% and a butyralization degree of 69 mol% (Abbreviation 3GO) 40 parts by weight was added and kneaded sufficiently with a mixing roll, and then press molded at 150 ° C. for 30 minutes using a press molding machine to obtain a protective layer having an average film thickness of 0.33 mm.
An interlayer film for laminated glass and a laminated glass were produced in the same manner as in Example 1 using the obtained sound insulating layer and protective layer.

Example 4
In the production of the sound insulating layer, polyvinyl butyral having an acetylation degree of 4 mol% and a butyral degree of 71 mol% was used, and the film thickness of the sound insulating layer was changed to 0.12 mm. A film and laminated glass were produced.

(Example 5)
In the production of the sound insulating layer, polyvinyl butyral having an acetylation degree of 5 mol% and a butyral degree of 70 mol% was used, and the film thickness of the sound insulating layer was changed to 0.12 mm. A film and laminated glass were produced.

(Example 6)
An interlayer film for laminated glass and laminated glass were produced in the same manner as in Example 1 except that polyvinyl butyral having an acetylation degree of 6 mol% and a butyralization degree of 69 mol% was used in the production of the sound insulation layer.

(Example 7)
An interlayer film for laminated glass and laminated glass were produced in the same manner as in Example 1 except that polyvinyl butyral having an acetylation degree of 7 mol% and a butyralization degree of 68 mol% was used in the production of the sound insulation layer.

(Comparative Example 1)
An interlayer film for laminated glass and laminated glass were produced in the same manner as in Example 1 except that polyvinyl butyral having an acetylation degree of 9 mol% and a butyralization degree of 68 mol% was used in the production of the sound insulation layer.

(Comparative Example 2)
An interlayer film for laminated glass in the same manner as in Example 1 except that polyvinyl butyral having an acetylation degree of 1 mol% and a butyralization degree of 60 mol% was used in the production of the sound insulation layer, and the plasticizer content was 40 parts by weight. And the laminated glass was produced.

<Evaluation>
The following evaluation was performed about the interlayer film for laminated glass and laminated glass obtained in Examples 1 to 7 and Comparative Examples 1 and 2. The results are shown in Tables 1 and 2.

(1) Evaluation of sound insulation property The obtained interlayer film for laminated glass is cut into a size of 4 mm × 4 mm and sandwiched between transparent float glasses (length 4 mm × width 4 mm × thickness 2.3 mm), and this is put into a rubber bag. Then, after deaeration for 20 minutes at a vacuum degree of 20 torr, it was transferred to an oven while being deaerated, and further vacuum pressed while maintaining at 90 ° C. for 30 minutes. The preliminarily pressure-bonded laminated glass was pressure-bonded for 20 minutes in an autoclave under conditions of 135 ° C. and a pressure of 1176 kPa to produce a laminated glass for sound insulation evaluation.
This laminated glass for sound insulation evaluation is vibrated by a vibration generator for vibration test (manufactured by KENKEN Co., Ltd., shaker G21-005D), and the vibration characteristics obtained therefrom are mechanical impedance amplifiers (manufactured by RION, XG- 81), and the vibration spectrum was analyzed with an FFT spectrum analyzer (manufactured by Yokogawa Hewlett Packard, FFT analyzer HP3582A).
From the ratio of the loss factor thus obtained and the resonance frequency with glass, a graph showing the relationship between the sound frequency (Hz) at 20 ° C. and the sound transmission loss (dB) is created, and the sound frequency is around 2000 Hz. The minimum sound transmission loss (TL value) was determined. The higher the TL value, the higher the sound insulation.

(2) Moisture resistance test 1
The obtained interlayer film for laminated glass was immersed in distilled water so as to be completely immersed, and left at 23 ° C. for 24 hours. The haze value of the interlayer film for laminated glass after standing was measured using an integral turbidimeter (manufactured by Tokyo Denshoku Co., Ltd.) by a method based on JIS K 6714.

(3) Moisture resistance test 2
In accordance with JIS R 3212 (1998), the obtained laminated glass is left in an atmosphere of 100 ° C. and 95% RH for 1 month, and then the distance of whitened portion (whitening distance) is measured from the periphery of the laminated glass. It was measured.

(4) Comprehensive determination Based on the evaluation of (1) to (3), comprehensive determination was performed according to the following criteria.
○: Haze value was 50% or less, and whitening distance was 2 mm or less.
X: Haze value exceeded 50% or whitening distance exceeded 2 mm.

ADVANTAGE OF THE INVENTION According to this invention, even if it gets wet, it does not whiten and can provide the intermediate film for laminated glasses and laminated glass which have the outstanding sound insulation.

Claims (2)

An interlayer film for laminated glass comprising a sound insulating layer and two protective layers sandwiching the sound insulating layer,
The sound insulation layer contains 60 to 75 parts by weight of a plasticizer with respect to 100 parts by weight of polyvinyl butyral having an acetylation degree of 7 mol% or less and a butyralization degree of 68 to 82 mol%,
The protective layer is plasticized with respect to 100 parts by weight of polyvinyl butyral having an acetylation degree of 4 mol% or less, a butyralization degree of 60 to 75 mol%, and a butyralization degree of polyvinyl butyral contained in the sound insulation layer. An interlayer film for laminated glass, comprising 20 to 45 parts by weight of an agent. A laminated glass comprising the interlayer film for laminated glass according to claim 1.