JP2013006727A - Interlayer for laminated glass and laminated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interlayer for laminated glass having high adhesiveness between layers or suppressing generation of bubbles even by using the laminated glass in a high-temperature environment.SOLUTION: The interlayer 1 for laminated glass is provided with a first layer 2 and a second layer 3 laminated to one face 2a of the first layer 2. The first and second layers 2, 3 contain a polyvinyl acetal resin and a plasticizer. The acetylation degree of the polyvinyl acetal resin in the first layer 2 may be ≤8 mol% or >8 mol%. The acetylation degree of the polyvinyl acetal resin in the second layer 3 is >8 mol%. The content of hydroxyl group of the polyvinyl acetal resin in the first layer 2 is smaller than the content of hydroxyl group of the polyvinyl acetal resin in the second layer 3, and the difference between the hydroxyl group content of the polyvinyl acetal resin in the first layer 2 and the hydroxyl group content of the polyvinyl acetal resin in the second layer 3 is ≤12 mol% or ≤11.5 mol%.

Description

  The present invention relates to an interlayer film for laminated glass having a multilayer structure of at least two layers, and more specifically, an interlayer film for laminated glass in which each layer contains a polyvinyl acetal resin and a plasticizer, respectively, and the interlayer film for laminated glass It is related with the laminated glass using.

  Laminated glass is excellent in safety because it has less scattering of glass fragments even if it is damaged by external impact. For this reason, the said laminated glass is widely used for a motor vehicle, a rail vehicle, an aircraft, a ship, a building, etc. The laminated glass is manufactured by sandwiching an interlayer film for laminated glass between a pair of glass plates.

  As an example of the interlayer film for laminated glass, the following Patent Document 1 discloses that 100 parts by weight of a polyvinyl acetal resin having an acetalization degree of 60 to 85 mol%, and at least one of an alkali metal salt and an alkaline earth metal salt. A sound insulation layer containing 0.001 to 1.0 parts by weight of a metal salt of and 30 parts by weight or more of a plasticizer is disclosed. This sound insulation layer may be a single layer and used as an intermediate film.

  Furthermore, the following Patent Document 1 also describes a multilayer intermediate film in which the sound insulation layer and other layers are laminated. The other layer laminated on the sound insulation layer is composed of 100 parts by weight of a polyvinyl acetal resin having an acetalization degree of 60 to 85 mol%, and at least one metal salt of an alkali metal salt and an alkaline earth metal salt 0.001 to 0.001. 1.0 part by weight and a plasticizer of 30 parts by weight or less are included.

JP 2007-070200 A

  When the laminated glass is formed using the interlayer film described in Patent Document 1, the sound insulation in the frequency region near 2000 Hz of the laminated glass is not sufficient, and therefore the sound insulation performance is inevitably lowered due to the coincidence effect. There is. In particular, the sound insulation properties at around 20 ° C. of this laminated glass may not be sufficient.

  Here, the coincidence effect means that when a sound wave is incident on the glass plate, the 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. This is a phenomenon that occurs.

  In addition, when a laminated glass is formed using a multilayer interlayer film in which the sound insulating layer described in Patent Document 1 and other layers are laminated, the sound insulating property in the vicinity of 20 ° C. of the laminated glass can be increased to some extent. it can. Thus, the examination which raises the sound-insulating property of a laminated glass using a multilayer interlayer film is performed.

  In recent years, in order to increase the sound insulation of laminated glass, it has been studied to increase the content of the plasticizer in the interlayer film. When the content of the plasticizer in the interlayer film is increased, the sound insulation of the laminated glass can be improved. In the multilayer interlayer film, in order to increase the plasticizer content in the sound insulation layer of the multilayer interlayer film, the transition between the plasticizer contained in the sound insulation layer and the plasticizer contained in other layers is controlled. is doing. For example, in order to improve the sound insulation, even if the plasticizer is transferred between the respective layers, it is necessary to make the content of the plasticizer in the sound insulation layer larger than the content of the plasticizer in the other layers after the transfer. For this reason, the compatibility of the plasticizer with the resin contained in the sound insulation layer and the compatibility of the plasticizer with the resin contained in the other layers are adjusted. More specifically, the resin contained in the sound insulation layer needs to have higher compatibility with the plasticizer than the resin contained in the other layers. Therefore, different resins having a difference in compatibility with the plasticizer are generally used for the resin contained in the sound insulation layer and the resin contained in another layer. As a result, the difference in polarity between the resin contained in the sound insulation layer and the resin contained in the sound insulation layer becomes large, and the adhesive force between the sound insulation layer and other layers in the multilayer intermediate film may be reduced.

  In addition, the use of laminated glass is increasing in side windows of vehicles such as automobiles and openings in buildings. When laminated glass is used for side glass or the like, the intermediate film may be exposed at the periphery of the laminated glass. When a laminated glass having an intermediate film exposed at the periphery is used in a high temperature environment, foaming may occur at the periphery of the laminated glass. In particular, when a laminated glass having an intermediate film having a sound insulation layer containing a large amount of plasticizer is exposed at the periphery in a high temperature environment, foaming may occur at the periphery of the laminated glass.

  An object of the present invention is to provide an interlayer film for laminated glass that is a multilayer interlayer film and has high adhesion between the layers, and a laminated glass using the interlayer film for laminated glass. Another object of the present invention is to provide an interlayer film for laminated glass that can suppress foaming even when laminated glass is used in a high temperature environment, and a laminated glass using the interlayer film for laminated glass. That is.

  A limited object of the present invention is to provide an interlayer film for laminated glass capable of obtaining a laminated glass excellent in sound insulation, and a laminated glass using the interlayer film for laminated glass.

  According to a wide aspect of the present invention, a first layer containing a polyvinyl acetal resin and a plasticizer is laminated on one surface of the first layer, and contains a polyvinyl acetal resin and a plasticizer. The polyvinyl acetal resin in the first layer is 8 mol% or less, and the polyvinyl acetal resin in the second layer has an acetylation degree of 8 mol%. %, The hydroxyl group content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl group content of the polyvinyl acetal resin in the second layer, and in the first layer Provided is an interlayer film for laminated glass in which the difference between the hydroxyl group content of the polyvinyl acetal resin and the hydroxyl group content of the polyvinyl acetal resin in the second layer is 12 mol% or less. That.

  According to a wide aspect of the present invention, a first layer containing a polyvinyl acetal resin and a plasticizer is laminated on one surface of the first layer, and the polyvinyl acetal resin and the plasticizer are The polyvinyl acetal resin in the first layer exceeds 8 mol%, and the polyvinyl acetal resin in the second layer has an acetylation degree of 8%. More than mol%, the hydroxyl group content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl group content of the polyvinyl acetal resin in the second layer, Provided is an interlayer film for laminated glass, wherein the difference between the hydroxyl group content of the polyvinyl acetal resin and the hydroxyl group content of the polyvinyl acetal resin in the second layer is 11.5 mol% or less. It is.

  In the interlayer film for laminated glass according to the present invention, the degree of acetylation of the polyvinyl acetal resin in the first layer may be 8 mol% or less, or may exceed 8 mol%.

  In a specific aspect of the interlayer film for laminated glass according to the present invention, the polyvinyl acetal resin in the second layer has a hydroxyl group content of 30 mol% or less, or the polyvinyl in the second layer. The hydroxyl group content of the acetal resin is 29 mol% or less, or the hydroxyl group content of the polyvinyl acetal resin in the second layer is 28 mol% or less.

  In another specific aspect of the interlayer film for laminated glass according to the present invention, the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is equal to the polyvinyl acetal in the second layer. The content of the plasticizer is more than 100 parts by weight of the resin.

  In another specific aspect of the interlayer film for laminated glass according to the present invention, the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is the polyvinyl acetal in the second layer. 20 parts by weight or more than the content of the plasticizer with respect to 100 parts by weight of the resin.

  In still another specific aspect of the interlayer film for laminated glass according to the present invention, when the degree of acetylation of the polyvinyl acetal resin in the first layer is 8 mol% or less, the other of the first layer A third layer containing a polyvinyl acetal resin and a plasticizer is further provided, and the degree of acetylation of the polyvinyl acetal resin in the third layer exceeds 8 mol%, The hydroxyl content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl content of the polyvinyl acetal resin in the third layer, and the polyvinyl acetal resin in the first layer. The difference between the hydroxyl group content and the hydroxyl content of the polyvinyl acetal resin in the third layer is 12 mol% or less.

  In still another specific aspect of the interlayer film for laminated glass according to the present invention, when the degree of acetylation of the polyvinyl acetal resin in the first layer exceeds 8 mol%, the other layer of the first layer A third layer that is laminated to the surface and contains a polyvinyl acetal resin and a plasticizer, and the degree of acetylation of the polyvinyl acetal resin in the third layer exceeds 8 mol%, The hydroxyl group content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl group content of the polyvinyl acetal resin in the third layer, and the polyvinyl acetal resin in the first layer The difference between the hydroxyl group content and the hydroxyl content of the polyvinyl acetal resin in the third layer is 11.5 mol% or less.

  In another specific aspect of the interlayer film for laminated glass according to the present invention, the content of hydroxyl groups of the polyvinyl acetal resin in the third layer is 30 mol% or less, or the above-mentioned in the third layer. The hydroxyl group content of the polyvinyl acetal resin is 29 mol% or less, or the hydroxyl group content of the polyvinyl acetal resin in the third layer is 28 mol% or less.

  In still another specific aspect of the interlayer film for laminated glass according to the present invention, the plasticizer content in 100 parts by weight of the polyvinyl acetal resin in the first layer is in the second and third layers. The content of the plasticizer is more than 100 parts by weight of the polyvinyl acetal resin.

  In another specific aspect of the interlayer film for laminated glass according to the present invention, the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is in the second and third layers. The amount of the plasticizer is 20 parts by weight or more than 100 parts by weight of the polyvinyl acetal resin.

  In still another specific aspect of the interlayer film for laminated glass according to the present invention, each of the polyvinyl acetal resins contained in the first to third layers includes a polyvinyl butyral resin, and the first to third Each of the plasticizers contained in the layer comprises triethylene glycol di-2-ethylhexanoate.

  The laminated glass according to the present invention comprises first and second laminated glass constituent members and an intermediate film sandwiched between the first and second laminated glass constituent members, and the intermediate film comprises: 1 is an interlayer film for laminated glass constructed according to the present invention.

  In the interlayer film for laminated glass according to the present invention, the second layer containing the polyvinyl acetal resin and the plasticizer is laminated on one surface of the first layer containing the polyvinyl acetal resin and the plasticizer. Further, the degree of acetylation of the polyvinyl acetal resin in the first layer is 8 mol% or less, the degree of acetylation of the polyvinyl acetal resin in the second layer exceeds 8 mol%, and the first The hydroxyl content of the polyvinyl acetal resin in the layer is lower than the hydroxyl content of the polyvinyl acetal resin in the second layer, and the hydroxyl content of the polyvinyl acetal resin in the first layer is Since the difference between the content and the hydroxyl content of the polyvinyl acetal resin in the second layer is 12 mol% or less, the adhesion between each layer of the multilayer interlayer film is increased. It is possible. Furthermore, generation | occurrence | production of foaming can be suppressed when the laminated glass using the intermediate film for laminated glasses which concerns on this invention is used in a high temperature environment.

  In the interlayer film for laminated glass according to the present invention, the second layer containing the polyvinyl acetal resin and the plasticizer is laminated on one surface of the first layer containing the polyvinyl acetal resin and the plasticizer. And the acetylation degree of the polyvinyl acetal resin in the first layer exceeds 8 mol%, the acetylation degree of the polyvinyl acetal resin in the second layer exceeds 8 mol%, The hydroxyl group content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl group content of the polyvinyl acetal resin in the second layer, and the hydroxyl group of the polyvinyl acetal resin in the first layer. And the difference between the hydroxyl group content of the polyvinyl acetal resin in the second layer is 11.5 mol% or less, Can Kusuru. Furthermore, generation | occurrence | production of foaming can be suppressed when the laminated glass using the intermediate film for laminated glasses which concerns on this invention is used in a high temperature environment.

FIG. 1 is a cross-sectional view schematically showing an interlayer film for laminated glass according to an embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing an example of a laminated glass using the laminated glass interlayer film shown in FIG.

  Hereinafter, the present invention will be clarified by giving specific embodiments and examples of the present invention with reference to the drawings.

  In FIG. 1, the intermediate film for laminated glasses which concerns on one Embodiment of this invention is typically shown with sectional drawing.

  The intermediate film 1 shown in FIG. 1 includes a first layer 2, a second layer 3 stacked on one surface 2 a (first surface) of the first layer 2, and the other of the first layer 2. And a third layer 4 laminated on the surface 2b (second surface). The intermediate film 1 is used to obtain a laminated glass. The intermediate film 1 is an intermediate film for laminated glass. The intermediate film 1 is a multilayer intermediate film.

  In the present embodiment, the first layer 2 is an intermediate layer, and the second and third layers 3 and 4 are surface layers. However, the second and third layers 3 and 4 are intermediate layers, and other interlayer films for laminated glass are further laminated on the outer surfaces 3a and 4a of the second and third layers 3 and 4. May be.

  Each of the first to third layers 2 to 4 contains a polyvinyl acetal resin and a plasticizer.

  The main feature of this embodiment is that the degree of acetylation of the polyvinyl acetal resin in the first layer 2 is 8 mol% or less, and the acetylation of the polyvinyl acetal resin in the second and third layers 3 and 4. The degree of conversion exceeds 8 mol%, and the hydroxyl group content of the polyvinyl acetal resin in the first layer 2 is lower than the hydroxyl group content of the polyvinyl acetal resin in the second layer 3; The difference between the hydroxyl group content of the polyvinyl acetal resin in the first layer 2 and the hydroxyl group content of the polyvinyl acetal resin in the second layer 3 (hereinafter referred to as a content difference (1-2)). May be 12 mol% or less.

  Moreover, in this embodiment, the acetylation degree of the said polyvinyl acetal resin in the 3rd layer 4 exceeds 8 mol% or less, and also the content rate of the hydroxyl group of the said polyvinyl acetal resin in the 1st layer 2 is The hydroxyl content of the polyvinyl acetal resin in the third layer 4 is lower than the hydroxyl content of the polyvinyl acetal resin in the third layer 4, and the hydroxyl content of the polyvinyl acetal resin in the first layer 2 and the polyvinyl acetal resin in the third layer 4. The difference from the hydroxyl group content (hereinafter sometimes referred to as a content difference (1-3)) is 12 mol% or less.

  In the interlayer film for laminated glass having a multilayer structure, the present inventors have found that a plasticizer migrates between the respective layers, and as a result, a layer having a high plasticizer content is formed. It was found that the plasticizer migrated from the first layer to the first layer, and as a result, the plasticizer content in the first layer increased. Furthermore, in order to control the migration of the plasticizer between the layers, the adhesive force between the layers of the multilayer intermediate film may be lowered. Further, the present inventors have found that when a laminated glass having an intermediate film exposed at the peripheral portion is used in a high temperature environment, foaming occurs in the peripheral portion of the glass.

  The inventors of the present invention have made extensive studies in order to increase the adhesive force between the layers of the multilayer interlayer film and to suppress the occurrence of foaming. As a result, each of the polyvinyl acetal resins in the first to third layers has been studied. By controlling the degree of acetylation and the content of each hydroxyl group as described above, the adhesion between each layer of the multilayer interlayer film can be increased, and even if laminated glass is used in a high temperature environment, foaming can be achieved. It has been found that the occurrence of can be suppressed.

  Another feature of this embodiment is that the plasticizer content relative to 100 parts by weight of the polyvinyl acetal resin in the first layer 2 is based on 100 parts by weight of the polyvinyl acetal resin in the second layer 3. It is more than the content of the plasticizer. Moreover, in this embodiment, content of the said plasticizer with respect to 100 weight part of the said polyvinyl acetal resin in the 1st layer 2 is content of the said plasticizer with respect to 100 weight part of the said polyvinyl acetal resin in the 3rd layer 4. More than quantity. The degree of acetylation of the polyvinyl acetal resin of the first to third layers 2, 3, 4 when satisfying the above relationship of the plasticizer content in the first to third layers 2, 3, 4 In addition, by controlling the content of each hydroxyl group as described above, the adhesion between each layer of the multilayer interlayer film is effectively increased, and even when laminated glass is used in a high-temperature environment, foaming is not generated. It can be effectively suppressed.

  The content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer 2 is the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the second and third layers 3 and 4. In the case where the amount is more than that, the sound insulation of the laminated glass can be sufficiently enhanced.

  In addition, although the acetylation degree of the polyvinyl acetal resin in the 1st layer 2 is 8 mol% or less, the acetylation degree of the polyvinyl acetal resin in the 1st layer 2 may exceed 8 mol%. When the degree of acetylation of the polyvinyl acetal resin in the first layer 2 exceeds 8 mol%, the hydroxyl group content of the polyvinyl acetal resin in the first layer 2 and the polyvinyl in the second layer 3 The difference from the hydroxyl group content of the acetal resin (hereinafter sometimes referred to as a content difference (1-2)) is 11.5 mol% or less. When the degree of acetylation of the polyvinyl acetal resin in the first layer 2 exceeds 8 mol%, the hydroxyl group content of the polyvinyl acetal resin in the first layer is in the third layer 4. The difference between the hydroxyl group content of the polyvinyl acetal resin in the first layer 2 and the hydroxyl group content of the polyvinyl acetal resin in the third layer 4 is lower than the hydroxyl group content of the polyvinyl acetal resin. (Hereinafter, it may be described as a content difference (1-3)) is preferably 11.5 mol% or less.

  From the viewpoint of increasing the adhesion between each layer of the multilayer interlayer film and further suppressing the occurrence of foaming, the hydroxyl group content of the polyvinyl acetal resin in the first layer 2 and the second and third layers The preferable lower limit of the difference (content ratio difference (1-2) and content ratio difference (1-3)) with respect to the content of each hydroxyl group in the polyvinyl acetal resin in 3, 4 is 0.1 mol%, more preferable lower limit. Is 1 mol%, a more preferred lower limit is 2 mol%, a preferred upper limit is 11.5 mol%, a preferred upper limit is 11.2 mol%, a preferred upper limit is 11 mol%, a preferred upper limit is 10.5 mol%, and a preferred upper limit is 10 mol%, and a preferable upper limit is 9.5 mol%. Since the adhesive force between the respective layers of the multilayer interlayer film can be increased and the occurrence of foaming can be further suppressed, the hydroxyl content of the polyvinyl acetal resin in the first layer 2 and the second and third The difference (content ratio difference (1-2) and content ratio difference (1-3)) between each hydroxyl group content of the polyvinyl acetal resin in the layers 3 and 4 is preferably 8.5 mol% or less, more preferably. Is not more than 7.5 mol%, more preferably not more than 6.5 mol%, still more preferably not more than 3.5 mol%.

  Moreover, when the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer 2 is 55 parts by weight or more, the sound insulation of the laminated glass can be sufficiently enhanced. When the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer 2 is 60 parts by weight or more, the sound insulation of the laminated glass can be further enhanced.

  Hereinafter, the detail of each component contained in the said 1st-3rd layer of an intermediate film is demonstrated.

(Polyvinyl acetal resin)
When the first to third layers each contain a polyvinyl acetal resin and a plasticizer, the adhesive strength of the first to third layers can be increased. For this reason, the adhesive force of the intermediate film with respect to the laminated glass constituent member can be further increased.

  The polyvinyl acetal resin can be produced, for example, by acetalizing polyvinyl alcohol with an aldehyde. The polyvinyl alcohol can be obtained, for example, by saponifying polyvinyl acetate. The saponification degree of the polyvinyl alcohol is generally in the range of 70 to 99.9 mol%, and preferably in the range of 80 to 99.8 mol%.

  The degree of polymerization of the polyvinyl alcohol is preferably 200 or more, more preferably 500 or more, preferably 3000 or less, more preferably 2800 or less. When the said polymerization degree satisfy | fills the said preferable minimum, the penetration resistance of a laminated glass can be improved further. When the said polymerization degree satisfy | fills the said preferable upper limit, shaping | molding of an intermediate film will become easy. The polyvinyl acetal resin in the first layer is preferably a polyvinyl acetal resin obtained by acetalizing polyvinyl alcohol having a degree of polymerization of more than 1700 and 3000 or less. The degree of polymerization indicates an average degree of polymerization.

  The average degree of polymerization of the polyvinyl alcohol is determined by a method based on JIS K6726 “Testing method for polyvinyl alcohol”.

  The aldehyde is not particularly limited. In general, an aldehyde having 1 to 10 carbon atoms is preferably used as the aldehyde. Examples of the aldehyde having 1 to 10 carbon atoms include propionaldehyde, n-butyraldehyde, isobutyraldehyde, n-valeraldehyde, 2-ethylbutyraldehyde, n-hexylaldehyde, n-octylaldehyde, and n-nonylaldehyde. , N-decylaldehyde, formaldehyde, acetaldehyde, benzaldehyde and the like. Among these, n-butyraldehyde, n-hexylaldehyde or n-valeraldehyde is preferable, and n-butyraldehyde is more preferable. As for the said aldehyde, only 1 type may be used and 2 or more types may be used together.

  The polyvinyl acetal resin is preferably a polyvinyl butyral resin. The interlayer film for laminated glass according to the present invention preferably contains a polyvinyl butyral resin as the polyvinyl acetal resin contained in the first to third layers. Synthesis of polyvinyl butyral resin is easy. Furthermore, the use of the polyvinyl butyral resin allows the intermediate film to have a more appropriate adhesive force with respect to the laminated glass component. Furthermore, light resistance, weather resistance, etc. can be further improved.

  The preferable lower limit of the hydroxyl group content (hydroxyl group amount) of the polyvinyl acetal resin contained in the first layer is 20 mol%, the more preferable lower limit is 22 mol%, the still more preferable lower limit is 23 mol%, and the particularly preferable lower limit is 25 mol%, a preferred upper limit is 30 mol%, a more preferred upper limit is 28 mol%, a still more preferred upper limit is 27 mol%, and a particularly preferred upper limit is 26 mol%. When the hydroxyl group content satisfies the preferable lower limit, the adhesive strength of the first layer can be further increased. When the hydroxyl group content satisfies the preferable upper limit, the sound insulating properties of the laminated glass can be further enhanced. Furthermore, the flexibility of the intermediate film is increased, and the handleability of the intermediate film can be further enhanced. The first layer may be an intermediate layer.

  In addition, when the content rate of the hydroxyl group of the said polyvinyl acetal resin is low, the hydrophilic property of a polyvinyl acetal resin will become low. For this reason, content of a plasticizer can be increased and as a result, the sound insulation of a laminated glass can be made still higher. The hydroxyl group content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl group content of the polyvinyl acetal resin in the second and third layers. The plasticizer content can be increased.

  The preferable lower limit of the hydroxyl group content of the polyvinyl acetal resin contained in the second and third layers is 10 mol%, the more preferable lower limit is 15 mol%, the still more preferable lower limit is 18 mol%, and the particularly preferable lower limit is 21 mol%, a preferred upper limit is 33 mol%, a more preferred upper limit is 30 mol%, a still more preferred upper limit is 29 mol%, and a particularly preferred upper limit is 28 mol%. When the hydroxyl group content satisfies the preferable lower limit, the adhesive strength of the intermediate film can be further increased. When the hydroxyl group content satisfies the preferable upper limit, the flexibility of the intermediate film is increased, and the handleability of the intermediate film can be further enhanced.

  The content of hydroxyl groups in the polyvinyl acetal resin is a value obtained by dividing the amount of ethylene groups to which hydroxyl groups are bonded by the total amount of ethylene groups in the main chain, as a percentage (mol%). . The amount of ethylene group to which the hydroxyl group is bonded can be determined, for example, by measuring the amount of ethylene group to which the hydroxyl group of the polyvinyl acetal resin is bonded by a method based on JIS K6728 “Testing method for polyvinyl butyral”. it can.

  As the polyvinyl acetal resin contained in the first layer, a polyvinyl acetal resin (hereinafter also referred to as “polyvinyl acetal resin A”) having an acetylation degree (acetyl group amount) of 8 mol% or less may be used. Alternatively, a polyvinyl acetal resin having a degree of acetylation exceeding 8 mol% (hereinafter also referred to as “polyvinyl acetal resin B”) may be used. When the polyvinyl acetal resin contained in the first layer is the polyvinyl acetal resin A, the content difference (1-2) and the content difference (1-3) are preferably 12 mol% or less, It is more preferably 11.5 mol% or less, and further preferably 11 mol% or less. Moreover, when the said polyvinyl acetal resin contained in the said 1st layer is the polyvinyl acetal resin B, content rate difference (1-2) and content rate difference (1-3) are 12 mol% or less. It is preferably 11.5 mol% or less, more preferably 11 mol% or less.

  The upper limit of the degree of acetylation a of the polyvinyl acetal resin A is 8 mol%, the preferable upper limit is 7 mol%, the more preferable upper limit is 6 mol%, the still more preferable upper limit is 5 mol%, and the preferable lower limit is 0.1 mol%. A preferred lower limit is 0.5 mol%, a more preferred lower limit is 1 mol%, and a particularly preferred lower limit is 1.5 mol%. When the acetylation degree a is not more than the above upper limit and not less than the above lower limit, the migration of the plasticizer can be easily controlled, and the sound insulation of the laminated glass can be further enhanced.

  A preferable lower limit of the degree of acetalization a of the polyvinyl acetal resin A is 68 mol%, a more preferable lower limit is 70 mol%, a further preferable lower limit is 71 mol%, a particularly preferable lower limit is 72 mol%, and a preferable upper limit is 85 mol%. A preferred upper limit is 83 mol%, a more preferred upper limit is 81 mol%, and a particularly preferred upper limit is 79 mol%. When the acetalization degree a is not less than the above lower limit, the sound insulation of the laminated glass can be further enhanced. When the acetalization degree a is not more than the above upper limit, the reaction time necessary for producing the polyvinyl acetal resin A can be shortened.

  The hydroxyl group content a of the polyvinyl acetal resin A is preferably less than 31.5 mol%, more preferably 31 mol% or less, still more preferably 29 mol% or less, still more preferably 28 mol% or less, preferably 20 mol. % Or more, more preferably 21 mol% or more, still more preferably 22 mol% or more, and particularly preferably 24 mol% or more. When the hydroxyl group content a is not more than the above upper limit, the sound insulation of the laminated glass can be further enhanced. When the hydroxyl group content a is equal to or higher than the lower limit, the adhesive strength of the intermediate film can be further increased.

  The polyvinyl acetal resin A is preferably a polyvinyl butyral resin.

  The degree of acetylation b of the polyvinyl acetal resin B exceeds 8 mol%, the preferable lower limit is 10 mol%, the more preferable lower limit is 11 mol%, the still more preferable lower limit is 12 mol%, and the particularly preferable lower limit is 15 mol%, preferably. The upper limit is 30 mol%, the more preferable upper limit is 28 mol%, the still more preferable upper limit is 26 mol%, and the particularly preferable upper limit is 19.5 mol%. When the acetylation degree b is not less than the above lower limit, the sound insulation of the laminated glass can be further enhanced. When the acetylation degree b is not more than the above upper limit, the reaction time required for producing the polyvinyl acetal resin B can be shortened. Especially, since reaction time required in order to manufacture polyvinyl acetal resin B can be shortened further, it is preferable that the acetylation degree b of the said polyvinyl acetal resin B is less than 20 mol%. Moreover, since the generation | occurrence | production of foaming and the growth of foaming can further be suppressed in a laminated glass, it is preferable that the acetylation degree b of the polyvinyl acetal resin B is 25 mol% or less.

  The preferable lower limit of the degree of acetalization b of the polyvinyl acetal resin B is 45 mol%, the more preferable lower limit is 52.5 mol%, the still more preferable lower limit is 55 mol%, the particularly preferable lower limit is 60 mol%, and the preferable upper limit is 80 mol%. A more preferred upper limit is 77 mol%, a still more preferred upper limit is 74 mol%, and a particularly preferred upper limit is 71 mol%. When the acetalization degree b is equal to or higher than the lower limit, the sound insulation of the laminated glass can be further enhanced. When the acetalization degree b is not more than the above upper limit, the reaction time required for producing the polyvinyl acetal resin B can be shortened.

  The preferable upper limit of the hydroxyl group content b of the polyvinyl acetal resin B is 31.5 mol%, the more preferable upper limit is 30 mol%, the still more preferable upper limit is 29 mol%, the particularly preferable upper limit is 27.5 mol%, and the preferable lower limit is 22 mol%, a more preferred lower limit is 23 mol%, a still more preferred lower limit is 24 mol%, and a particularly preferred lower limit is 25 mol%. When the hydroxyl group content b is not more than the above upper limit, the sound insulation of the laminated glass can be further enhanced. When the hydroxyl group content b is not less than the above lower limit, the adhesive strength of the intermediate film can be further increased.

  The degree of acetylation of the polyvinyl acetal resin contained in the second layer exceeds 8 mol%. When the degree of acetylation exceeds 8 mol%, the adhesive strength between the respective layers of the multilayer intermediate film is increased, and the occurrence of foaming can be further suppressed. The degree of acetylation of the polyvinyl acetal resin contained in the third layer is preferably more than 8 mol%. The preferable lower limit of the degree of acetylation of the polyvinyl acetal resin contained in the second and third layers is 8.5 mol%, the more preferable lower limit is 9 mol%, and the more preferable lower limit is 9.5 mol%, preferably The upper limit is 30 mol%, the more preferred upper limit is 25 mol%, the still more preferred upper limit is 20 mol%, and the particularly preferred upper limit is 15 mol%. When the acetylation degree satisfies the preferable lower limit, the compatibility between the polyvinyl acetal resin and the plasticizer is further enhanced, and the glass transition temperature of the interlayer film can be sufficiently lowered. When the acetylation degree satisfies the preferable upper limit, the moisture resistance of the intermediate film can be further enhanced.

  When the polyvinyl acetal resin contained in the first layer is the polyvinyl acetal resin A, the sound insulation of the laminated glass is further enhanced, and therefore the degree of acetylation of the polyvinyl acetal resin A is It is preferably lower than the degree of acetylation of the polyvinyl acetal resin contained in the third layer, preferably 0.5 mol% or less, preferably 1 mol% or less, preferably 1.5 mol% or less. It is preferably 2 mol% or less, preferably 2.5 mol% or less, preferably 3 mol% or more, preferably 3.5 mol% or less, preferably 4 mol% or less. It is preferably 4.5 mol% or less, preferably 5 mol% or less.

  When the polyvinyl acetal resin contained in the first layer is the polyvinyl acetal resin B, the sound insulation of the laminated glass is further enhanced, so the degree of acetylation of the polyvinyl acetal resin B is It is preferably higher than the degree of acetylation of the polyvinyl acetal resin contained in the third layer, preferably 1 mol% or more, preferably 2 mol% or more, preferably 3 mol% or more, It is preferably 4 mol% or more, preferably 5 mol% or more, preferably 6 mol% or more, preferably 7 mol% or more, preferably 8 mol% or more, preferably 9 mol% or more. It is preferably 10 mol% or more.

  The degree of acetylation is obtained by subtracting the amount of ethylene groups to which acetal groups are bonded and the amount of ethylene groups to which hydroxyl groups are bonded from the total amount of ethylene groups of the main chain, This is a value expressed as a percentage (mol%) of the mole fraction obtained by dividing by. The amount of ethylene group to which the acetal group is bonded can be measured, for example, according to JIS K6728 “Testing method for polyvinyl butyral”.

  When the polyvinyl acetal resin contained in the first layer is the polyvinyl acetal resin A, the sound insulation of the laminated glass is further increased. Therefore, the degree of acetalization of the polyvinyl acetal resin A is the second, The degree of acetalization of the polyvinyl acetal resin contained in the third layer is preferably higher, preferably higher than 1 mol%, preferably higher than 2 mol%, preferably higher than 3 mol%, It is preferably 4 mol% or more, preferably 5 mol% or more, preferably 6 mol% or more, preferably 7 mol% or more, preferably 8 mol% or more, preferably 9 mol% or more. It is preferably 10 mol% or more.

  When the polyvinyl acetal resin contained in the first layer is the polyvinyl acetal resin B, the sound insulation of the laminated glass is further enhanced. Therefore, the degree of acetalization of the polyvinyl acetal resin B is the second, It is preferably higher than the degree of acetalization of the polyvinyl acetal resin contained in the third layer, preferably 0.5 mol% or more, preferably 1 mol% or more, preferably 1.5 mol% or more. It is preferably 2 mol% or more, preferably 2.5 mol% or more, preferably 3 mol% or more, preferably 3.5 mol% or more, preferably 4 mol% or more. It is preferably 4.5 mol% or more, preferably 5 mol% or more.

  The preferable lower limit of the degree of acetalization of the polyvinyl acetal resin contained in the second and third layers is 61 mol%, the more preferable lower limit is 65 mol%, the still more preferable lower limit is 67 mol%, and the preferable upper limit is 75 mol. %, A more preferred upper limit is 74 mol%, a still more preferred upper limit is 73 mol%, and a particularly preferred upper limit is 72 mol%. When the said acetalization degree satisfy | fills the said preferable minimum, the compatibility of polyvinyl acetal resin and a plasticizer becomes still higher, and the glass transition temperature of an intermediate film can fully be reduced. When the said acetalization degree satisfy | fills the said preferable upper limit, reaction time required in order to manufacture polyvinyl acetal resin can be shortened.

  The degree of acetalization is a value obtained by dividing the amount of ethylene groups to which acetal groups are bonded by the total amount of ethylene groups in the main chain, and expressed as a percentage (mol%).

  The degree of acetalization was determined by measuring the amount of acetyl groups and the amount of vinyl alcohol (hydroxyl content) by a method based on JIS K6728 “Testing methods for polyvinyl butyral”, and calculating the mole fraction from the obtained measurement results. Then, it can be calculated by subtracting the amount of acetyl groups and the amount of vinyl alcohol from 100 mol%.

  In order to increase the adhesive force between each layer of the multilayer interlayer film and suppress the occurrence of foaming, the hydroxyl group content of the polyvinyl acetal resin in the first to third layers is controlled as described above. do it.

  Regarding the polyvinyl acetal resin in the first layer, firstly, the degree of acetylation is preferably 8 mol% or less, and the hydroxyl group content is preferably less than 31.5 mol%, and secondly, The degree of acetylation is preferably 8 mol% or less, and the degree of acetalization is preferably 68 mol% or more. Third, the degree of acetylation is 8 mol% or less, and the hydroxyl group content is less than 31.5 mol%. The degree is preferably 68 mol% or more.

  Regarding the polyvinyl acetal resin in the first layer, first, it is preferable that the degree of acetylation exceeds 8 mol%, and the content of hydroxyl group is less than 31.5 mol%, and secondly The degree of acetylation exceeds 8 mol% and the degree of acetalization is preferably 60 mol% or more. Third, the degree of acetylation exceeds 8 mol% and the content of hydroxyl group is less than 31.5 mol%. The acetalization degree is preferably 60 mol% or more.

  The polyvinyl acetal resin A is obtained by acetalizing polyvinyl alcohol with an aldehyde. The aldehyde is preferably an aldehyde having 1 to 10 carbon atoms, and more preferably an aldehyde having 4 or 5 carbon atoms. Especially, it is preferable that the said polyvinyl acetal resin A is a polyvinyl acetal resin obtained by acetalizing the polyvinyl alcohol whose polymerization degree exceeds 1700 and is 3000 or less with an aldehyde. The preferable lower limit of the polymerization degree of the polyvinyl alcohol is 1800, more preferable lower limit is 2000, still more preferable lower limit is 2400, particularly preferable lower limit is 2500, preferable upper limit is 3000, more preferable upper limit is 2900, still more preferable upper limit is 2800, and particularly preferable upper limit. Is 2700. When the said polymerization degree satisfy | fills the said preferable minimum, the penetration resistance of a laminated glass can be improved further. When the said polymerization degree satisfy | fills the said preferable upper limit, shaping | molding of an intermediate film will become easy.

(Plasticizer)
The plasticizer contained in each of the first to third layers is not particularly limited. A conventionally known plasticizer can be used as the plasticizer. As for the said plasticizer, only 1 type may be used and 2 or more types may be used together.

  Examples of the plasticizer include organic ester plasticizers such as monobasic organic acid esters and polybasic organic acid esters, and phosphate plasticizers such as organic phosphate plasticizers and organic phosphorous acid plasticizers. It is done. Of these, organic ester plasticizers are preferred. The plasticizer is preferably a liquid plasticizer.

  The monobasic organic acid ester is not particularly limited. For example, a glycol ester obtained by reaction of glycol with a monobasic organic acid, and triethylene glycol or tripropylene glycol with a monobasic organic acid. Examples include esters. Examples of the glycol include triethylene glycol, tetraethylene glycol, and tripropylene glycol. Examples of the monobasic organic acid include butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptylic acid, n-octylic acid, 2-ethylhexylic acid, n-nonylic acid, and decylic acid.

  The polybasic organic acid ester is not particularly limited, and examples thereof include an ester compound of a polybasic organic acid and an alcohol having a linear or branched structure having 4 to 8 carbon atoms. Examples of the polybasic organic acid include adipic acid, sebacic acid, and azelaic acid.

  The organic ester plasticizer is not particularly limited, and triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethylene glycol di-n- Octanoate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, dibutyl sebacate, dioctyl azelate, dibutyl carbitol adipate, ethylene glycol di-2-ethyl butyrate, 1,3-propylene glycol di 2-ethyl butyrate, 1,4-butylene glycol di-2-ethyl butyrate, diethylene glycol di-2-ethyl butyrate, diethylene glycol di-2-ethyl hexanoate, dipropylene glycol Di-2-ethylbutyrate, triethylene glycol di-2-ethylpentanoate, tetraethylene glycol di-2-ethylbutyrate, diethylene glycol dicaprylate, dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, adipine Examples include a mixture of heptyl acid and nonyl adipate, diisononyl adipate, diisodecyl adipate, heptylnonyl adipate, dibutyl sebacate, alkyd oil-modified sebacic acid, and a mixture of phosphate ester and adipate. Organic ester plasticizers other than these may be used. Other adipic acid esters other than the above-mentioned adipic acid esters may be used.

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

  The plasticizer is preferably a diester plasticizer represented by the following formula (1). By using this diester plasticizer, the sound insulation of the laminated glass can be further enhanced.

  In said formula (1), R1 and R2 respectively represent a C5-C10 organic group, R3 represents an ethylene group, an isopropylene group, or n-propylene group, p represents the integer of 3-10. . R1 and R2 in the above formula (1) are each preferably an organic group having 6 to 10 carbon atoms.

  The plasticizer preferably contains a diester compound, and includes triethylene glycol di-2-ethylbutyrate (3GH), triethylene glycol di-2-ethylhexanoate (3GO), and triethylene glycol di-n-heptanoate. More preferably, it contains at least one selected from the group consisting of (3G7), and more preferably contains triethylene glycol di-2-ethylhexanoate. By using these preferable plasticizers, the sound insulation of the laminated glass can be further enhanced. The interlayer film for laminated glass according to the present invention particularly preferably contains triethylene glycol di-2-ethylhexanoate as the plasticizer contained in the first to third layers.

  The content of the plasticizer in each layer of the intermediate film is not particularly limited. From the viewpoint of sufficiently improving the sound insulation of the laminated glass, the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is preferably 40 parts by weight or more. Even if the content of the plasticizer in the first layer is large, the content of each hydroxyl group in the first to third layers is controlled as described above. Can be suppressed.

  The more preferable lower limit of the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is 50 parts by weight, the further preferable lower limit is 55 parts by weight, the particularly preferable lower limit is 60 parts by weight, and the preferable upper limit is 80 parts by weight. Part by weight, more preferred upper limit is 75 parts by weight, and still more preferred upper limit is 70 parts by weight. When content of the said plasticizer satisfy | fills the said preferable minimum, the penetration resistance of a laminated glass can be improved further. The greater the content of the plasticizer in the first layer, the higher the sound insulation of the laminated glass. When content of the said plasticizer satisfy | fills the said preferable upper limit, transparency of an intermediate film can be improved further. In order to sufficiently enhance the sound insulation of the laminated glass, the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is preferably 50 parts by weight or more. In addition, it is preferable that content of the said plasticizer with respect to 100 weight part of said polyvinyl acetal resins in said 1st layer is 50 weight part or more before transfer (initial stage) of a plasticizer, and 50 weight part or more after transfer. It may be. When 50 parts by weight of the plasticizer is blended with 100 parts by weight of the polyvinyl acetal resin in order to obtain the first layer, the content of the plasticizer in the first layer is generally There is a tendency to increase. In particular, when the content of the hydroxyl group of the polyvinyl acetal resin in the first layer is low, 50 parts by weight of the plasticizer is blended with 100 parts by weight of the polyvinyl acetal resin in order to obtain the first layer. In general, the content of the plasticizer in the first layer tends to increase.

  A preferable lower limit of each content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the second and third layers is 25 parts by weight, a more preferable lower limit is 28 parts by weight, and a still more preferable lower limit is 30 parts by weight. A preferred lower limit is 35 parts by weight, a preferred upper limit is 50 parts by weight, a more preferred upper limit is 45 parts by weight, a still more preferred upper limit is 40 parts by weight, and a particularly preferred upper limit is 39 parts by weight. When content of the said plasticizer satisfy | fills the said preferable minimum, the adhesive force of an intermediate film will become high and the penetration resistance of a laminated glass can be improved further. When content of the said plasticizer satisfy | fills the said preferable upper limit, transparency of an intermediate film can be improved further.

  From the viewpoint of further improving the sound insulation of the laminated glass, the content of the plasticizer relative to 100 parts by weight of the polyvinyl acetal resin in the first layer is the same as that of the polyvinyl acetal resin 100 in the second and third layers. It is preferable that the content of the plasticizer is more than the amount by weight. From the viewpoint of further improving the sound insulation of the laminated glass, the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is the same as that of the polyvinyl acetal resin in the second and third layers. It is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, still more preferably 15 parts by weight or more, and particularly preferably 20 parts by weight or more than the content of the plasticizer with respect to 100 parts by weight. More preferably, it is more than 25 parts by weight and most preferably more than 30 parts by weight.

(Other ingredients)
Each of the first to third layers is, if necessary, an ultraviolet absorber, an antioxidant, a light stabilizer, a flame retardant, an antistatic agent, a pigment, a dye, an adhesive force adjusting agent, a moisture resistant agent, and a fluorescent whitening. An additive such as an agent and an infrared absorber may be contained.

(Method for producing interlayer film for laminated glass and laminated glass)
Although it does not specifically limit as a manufacturing method of the intermediate film for laminated glasses which concerns on this invention, After forming the said 1st-3rd layer, respectively using the resin composition containing the said polyvinyl acetal resin and the said plasticizer. For example, a method of laminating the second layer, the first layer, and the third layer in this order, and coextruding the resin composition using an extruder, For example, a method of laminating a layer, the first layer, and the third layer in this order may be used. Since the production efficiency of the interlayer film is excellent, it is preferable that the second and third layers contain the same polyvinyl acetal resin, and the second and third layers contain the same polyvinyl acetal resin and More preferably, the same plasticizer is contained, and the second and third layers are more preferably formed of the same resin composition.

  Each of the interlayer films for laminated glass according to the present invention is used to obtain a laminated glass.

  FIG. 2 is a cross-sectional view schematically showing an example of a laminated glass using the intermediate film 1 shown in FIG.

  A laminated glass 11 shown in FIG. 2 includes a first laminated glass constituting member 12, a second laminated glass constituting member 13, and the intermediate film 1. The intermediate film 1 is sandwiched between the first and second laminated glass constituent members 12 and 13.

  The first laminated glass constituting member 12 is laminated on the outer surface 3 a of the second layer 3. The second laminated glass component 13 is laminated on the outer surface 4 a of the third layer 4. Accordingly, the laminated glass 11 is composed of the first laminated glass constituting member 12, the second layer 3, the first layer 2, the third layer 4, and the second laminated glass constituting member 13 in this order. It is laminated and configured. Although not shown, in the laminated glass 11, the intermediate film 1 is exposed at the peripheral portion. The intermediate film 1 is used for the laminated glass 11 so as to be exposed in at least a part of the peripheral portion of the laminated glass 11. Specifically, for example, the side surface of the intermediate film 1 is exposed. In the laminated glass, the intermediate film may be exposed in at least a part of the peripheral portion.

  Examples of the first and second laminated glass constituent members include glass plates and PET (polyethylene terephthalate) films. Laminated glass includes not only laminated glass in which an intermediate film is sandwiched between two glass plates, but also laminated glass in which an intermediate film is sandwiched between a glass plate and a PET film or the like. Laminated glass is a laminated body provided with a glass plate, and preferably at least one glass plate is used.

  Examples of the glass plate include inorganic glass and organic glass. Examples of the inorganic glass include float plate glass, heat ray absorbing plate glass, heat ray reflecting plate glass, polished plate glass, mold plate glass, netted plate glass, and lined plate glass. The organic glass is a synthetic resin glass substituted for inorganic glass. Examples of the organic glass include polycarbonate plates and poly (meth) acrylic resin plates. Examples of the poly (meth) acrylic resin plate include a polymethyl (meth) acrylate plate.

  From the viewpoint of further improving the penetration resistance of the laminated glass, the preferable lower limit of the thickness of the interlayer film is 0.05 mm, the more preferable lower limit is 0.25 mm, the preferable upper limit is 3 mm, and the more preferable upper limit is 1.5 mm. . When the thickness of the intermediate film satisfies the preferable lower limit and the preferable upper limit, the penetration resistance and transparency of the laminated glass can be further enhanced. The thickness of the first layer is preferably 0.01 mm or more, more preferably 0.04 mm or more, further preferably 0.07 mm or more, preferably 0.3 mm or less, more preferably 0.2 mm or less, and still more preferably 0. .18 mm or less, particularly preferably 0.16 mm or less. When the thickness of the first layer is not less than the above lower limit, the sound insulating property of the laminated glass is further enhanced. When the thickness of the first layer is not more than the upper limit, the transparency of the laminated glass is further increased. The thickness of the second and third layers is preferably 0.1 mm or more, more preferably 0.2 mm or more, still more preferably 0.25 mm or more, particularly preferably 0.3 mm or more, preferably 0.6 mm or less, more Preferably it is 0.5 mm or less, More preferably, it is 0.45 mm or less, Most preferably, it is 0.4 mm or less. When the thickness of the second and third layers is not less than the above lower limit, the penetration resistance of the laminated glass is further enhanced. When the thicknesses of the second and third layers are not more than the above upper limit, the transparency of the laminated glass is further increased. The ratio of the thickness of the first layer to the thickness of the intermediate film ((thickness of the first layer) / (thickness of the intermediate film)) is small, and the content of the plasticizer contained in the first layer As the amount increases, foaming occurs in the laminated glass and the foam tends to grow. In particular, when the ratio in the intermediate film is 0.05 or more and 0.35 or less, and the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is 55 parts by weight or more. Can sufficiently suppress the occurrence of foaming and the growth of foaming in the laminated glass using the interlayer film for laminated glass according to the present invention, and can further enhance the sound insulation of the laminated glass. The ratio ((the thickness of the first layer) / (the thickness of the intermediate film)) is preferably 0.06 or more, more preferably 0.07 or more, still more preferably 0.08 or more, and particularly preferably 0.1 or more. , Preferably 0.3 or less, more preferably 0.25 or less, still more preferably 0.2 or less, particularly preferably 0.15 or less.

  The thickness of the first and second laminated glass constituting members is preferably 0.5 mm or more, more preferably 1 mm or more, preferably 5 mm or less, more preferably 3 mm or less. Moreover, when the said laminated glass structural member is a glass plate, it is preferable that the thickness of this glass plate exists in the range of 1-3 mm. When the laminated glass component is a PET film, the thickness of the PET film is preferably in the range of 0.03 to 0.5 mm.

  The manufacturing method of the said laminated glass is not specifically limited. For example, the intermediate film is sandwiched between the first and second laminated glass constituent members, passed through a pressing roll, or put in a rubber bag and sucked under reduced pressure, and the first and second laminated glass The air remaining between the glass component and the intermediate film is degassed. Then, it pre-adheres at about 70-110 degreeC, and a laminated body is obtained. Next, the laminated body is put in an autoclave or pressed, and pressed at about 120 to 150 ° C. and a pressure of 1 to 1.5 MPa. In this way, the laminated glass can be obtained.

  The laminated glass can be used for automobiles, railway vehicles, aircraft, ships, buildings, and the like. Laminated glass can be used for other purposes. The laminated glass is preferably laminated glass for buildings or vehicles, and more preferably laminated glass for vehicles. Laminated glass can be used for a windshield, side glass, rear glass, roof glass, or the like of an automobile.

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

Example 1
(1) Production of multilayer interlayer film Polyvinyl butyral resin (hydroxyl content 22.1 mol%, acetylation degree 12.3 mol%, butyralization degree 65.6 mol%, polymerization degree 2350 polyvinyl alcohol is n-butyl) Resin that has been converted into butyral with aldehyde) 60 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) as a plasticizer is added to 100 parts by weight of resin, and kneaded thoroughly with a mixing roll. A composition was obtained. Furthermore, polyvinyl butyral resin (resin in which polyvinyl alcohol having a hydroxyl group content of 31 mol%, an acetylation degree of 12.5 mol%, a butyralization degree of 56.5 mol%, and a polymerization degree of 1700 is butyralized with n-butyraldehyde) To 100 parts by weight, 38.5 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) as a plasticizer was added and sufficiently kneaded with a mixing roll to obtain a resin composition for a surface layer.

  The obtained intermediate layer resin composition and surface layer resin composition were co-extruded using an extruder to obtain a surface layer (thickness 350 μm), an intermediate layer (thickness 100 μm), and a surface layer (thickness 350 μm). A multilayer interlayer film was prepared in which and were laminated in order.

(2) Production of laminated glass used for penetration resistance test and optical strain evaluation The obtained multilayer interlayer film was cut into a size of 30 cm in length and 30 cm in width. Next, a multilayer intermediate film was sandwiched between two transparent float glasses (length 30 cm × width 30 cm × thickness 2.5 mm) to obtain a laminate. This laminated body is put in a rubber bag, deaerated at a vacuum degree of 2.6 kPa for 20 minutes, transferred to an oven while being deaerated, and further kept at 90 ° C. for 30 minutes and vacuum-pressed. Crimped. The pre-pressed laminate was pressed in an autoclave at 135 ° C. and a pressure of 1.2 MPa for 20 minutes to obtain a laminated glass used for penetration resistance test and optical strain evaluation.

(3) Production of laminated glass used for sound insulation measurement Multilayer interlayer film is cut into a size of 30 cm in length x 2.5 cm in width, and transparent float glass (length 30 cm x width 2.5 cm x thickness 2.5 mm) is obtained. A laminated glass used for sound insulation measurement was obtained in the same manner as the laminated glass used for the penetration resistance test except that it was used.

(4) Production of laminated glass used for foaming test (bake test) The obtained multilayer interlayer film was cut into a size of 30 cm in length and 15 cm in width and stored in an environment at a temperature of 23 ° C. for 10 hours. In addition, embossing was formed on both surfaces of the obtained multilayer intermediate film, and the ten-point average roughness of the embossing was 30 μm. A multilayer intermediate film was sandwiched between two transparent float glasses (length 30 cm × width 15 cm × thickness 2.5 mm) to obtain a laminate. The laminated body was pressure-bonded for 20 minutes under the conditions of 135 ° C. and a pressure of 1.2 MPa to obtain a laminated glass used for the foaming test. In addition, the multilayer intermediate film was exposed in the peripheral part of the laminated glass used for a foaming test (baking test).

(Examples 2 to 20)
An interlayer film and a laminated glass were produced in the same manner as in Example 1 except that the compositions of the first to third layers were changed as shown in Table 1 below.

(Evaluation)
(1) Sound insulation The laminated glass is vibrated with a vibration generator for vibration testing ("Vibrator G21-005D" manufactured by KENKEN Co., Ltd.), and the vibration characteristics obtained therefrom are mechanical impedance measuring device (manufactured by RION Co., Ltd.). The vibration spectrum was analyzed with an FFT spectrum analyzer ("FFT analyzer HP3582A" manufactured by Yokogawa Hured Packard).

  From the ratio of the loss factor thus obtained and the resonance frequency of the laminated glass, a graph showing the relationship between the sound frequency (Hz) and the sound transmission loss (dB) at 20 ° C. is created. The minimum sound transmission loss (TL value) in the vicinity of 000 Hz was determined. The higher the TL value, the higher the sound insulation. The case where the TL value was 35 dB or more was determined as “◯”, and the case where the TL value was less than 35 dB was determined as “x”.

(2) Foam test (bake test)
Ten laminated glasses used for the foam test were prepared for each multilayer interlayer film and left in an oven at 80 ° C. for 100 hours. In the laminated glass after standing, the presence or absence of foaming in the peripheral part of the laminated glass was visually observed in a plan view, and the foamed state was judged according to the following criteria. In addition, the peripheral part of a laminated glass means the area | region within 1 cm from the edge part of a laminated glass.

[Criteria for foaming state by foaming test]
○: No foaming was observed in all 10 laminated glasses. ○: 1 or more and less than 3 laminated glasses were visually observed. Δ: Lamination was visually observed. The glass was 3 or more and less than 5 x: The laminated glass in which foaming was observed visually was 5 or more

(3) Penetration resistance The laminated glass (300 mm long x 300 mm wide) used for the penetration resistance test was adjusted so that the surface temperature was 23 ° C. Next, in accordance with JIS R3212, a rigid sphere having a mass of 2260 g and a diameter of 82 mm was dropped from the height of 4 m onto the center portion of the laminated glass for each of the six laminated glasses. For all six laminated glasses, the case where the hard sphere did not penetrate within 5 seconds after the collision of the hard sphere was regarded as acceptable. If the number of laminated glasses in which the hard sphere did not penetrate within 5 seconds after the collision of the hard sphere was 3 or less, it was rejected. In the case of four sheets, the penetration resistance of six new laminated glasses was evaluated. In the case of 5 sheets, one additional laminated glass was additionally tested, and the case where the hard sphere did not penetrate within 5 seconds after the collision of the hard sphere was regarded as acceptable. In the same manner, from a height of 5 m and 6 m, a rigid sphere having a mass of 2260 g and a diameter of 82 mm was dropped on the laminated glass of 6 sheets, and the penetration resistance of the laminated glass was evaluated. .

(4) Evaluation of bleed out On the surface of the obtained interlayer film, two lines each having a length of 10 cm were written and marked with a red oily magic in the vertical direction and the horizontal direction. The marked interlayer film was placed so that the main surface was located in a plane parallel to the vertical direction. This was left to stand for 1 month under constant temperature and humidity conditions of 23 ° C. and relative humidity of 28%. In the case where the oily magic bleed and sag are not observed on any of the four lines in the intermediate film after standing, the pass is “○”, and is observed on at least one of the four lines. Was rejected as “x”.

(5) Evaluation of optical distortion A laminated glass (length 30 cm x width 30 cm) used for optical distortion evaluation is irradiated with light transmitted through a slit from a light source (halogen lamp), and the projection distortion reflected on the screen is a sensor (camera). And processed by a computer to obtain an optical distortion value. A case where the optical distortion value was 1.8 or less was regarded as acceptable “◯”, and a case where it exceeded 1.8 was regarded as unacceptable “x”. It can be said that the higher the optical distortion value, the larger the optical distortion (distortion of the image).

  The results are shown in Table 1 below. In Table 1 below, PVB resin represents polyvinyl butyral resin, plasticizer type 3GO represents triethylene glycol di-2-ethylhexanoate, and 3GH represents triethylene glycol di-2-ethylbutyrate. .

DESCRIPTION OF SYMBOLS 1 ... Intermediate film 2 ... 1st layer 2a ... One side 2b ... The other side 3 ... 2nd layer 3a ... Outer surface 4 ... 3rd layer 4a ... Outer surface 11 ... Laminated glass 12 ... 1st Laminated glass constituent member 13 ... Second laminated glass constituent member

Claims (16)

A first layer containing a polyvinyl acetal resin and a plasticizer;
A second layer that is laminated on one side of the first layer and contains a polyvinyl acetal resin and a plasticizer;
The degree of acetylation of the polyvinyl acetal resin in the first layer is 8 mol% or less,
The degree of acetylation of the polyvinyl acetal resin in the second layer exceeds 8 mol%,
The hydroxyl content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl content of the polyvinyl acetal resin in the second layer, and the polyvinyl acetal resin in the first layer. The interlayer film for laminated glass, wherein the difference between the hydroxyl group content and the hydroxyl content of the polyvinyl acetal resin in the second layer is 12 mol% or less. A first layer containing a polyvinyl acetal resin and a plasticizer;
A second layer that is laminated on one side of the first layer and contains a polyvinyl acetal resin and a plasticizer;
The degree of acetylation of the polyvinyl acetal resin in the first layer exceeds 8 mol%,
The degree of acetylation of the polyvinyl acetal resin in the second layer exceeds 8 mol%,
The hydroxyl content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl content of the polyvinyl acetal resin in the second layer, and the polyvinyl acetal resin in the first layer. An interlayer film for laminated glass, wherein the difference between the hydroxyl group content and the hydroxyl content of the polyvinyl acetal resin in the second layer is 11.5 mol% or less.   The interlayer film for laminated glass according to claim 1 or 2, wherein the content of hydroxyl groups in the polyvinyl acetal resin in the second layer is 30 mol% or less.   The interlayer film for laminated glass according to claim 3, wherein the content of hydroxyl groups in the polyvinyl acetal resin in the second layer is 29 mol% or less.   The interlayer film for laminated glass according to claim 3, wherein the content of hydroxyl groups in the polyvinyl acetal resin in the second layer is 28 mol% or less.   The content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is larger than the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the second layer. The interlayer film for laminated glass according to any one of -5.   The content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is 20 parts by weight or more than the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the second layer. The interlayer film for laminated glass according to claim 6, wherein the interlayer film is large. A third layer laminated on the other surface of the first layer and containing a polyvinyl acetal resin and a plasticizer;
The degree of acetylation of the polyvinyl acetal resin in the third layer exceeds 8 mol%,
The hydroxyl content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl content of the polyvinyl acetal resin in the third layer, and the polyvinyl acetal resin in the first layer. The interlayer film for laminated glass according to claim 1, wherein the difference between the hydroxyl group content and the hydroxyl content of the polyvinyl acetal resin in the third layer is 12 mol% or less. A third layer laminated on the other surface of the first layer and containing a polyvinyl acetal resin and a plasticizer;
The degree of acetylation of the polyvinyl acetal resin in the third layer exceeds 8 mol%,
The hydroxyl content of the polyvinyl acetal resin in the first layer is lower than the hydroxyl content of the polyvinyl acetal resin in the third layer, and the polyvinyl acetal resin in the first layer. The interlayer film for laminated glass according to claim 2, wherein the difference between the hydroxyl group content and the hydroxyl content of the polyvinyl acetal resin in the third layer is 11.5 mol% or less.   The interlayer film for laminated glass according to claim 8 or 9, wherein the content of hydroxyl groups in the polyvinyl acetal resin in the third layer is 30 mol% or less.   The interlayer film for laminated glass according to claim 10, wherein the content of hydroxyl groups in the polyvinyl acetal resin in the third layer is 29 mol% or less.   The interlayer film for laminated glass according to claim 10, wherein the content of hydroxyl groups in the polyvinyl acetal resin in the third layer is 28 mol% or less.   Content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is larger than each content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the second and third layers. The interlayer film for laminated glass according to any one of claims 8 to 12.   The content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the first layer is 20 than the content of the plasticizer with respect to 100 parts by weight of the polyvinyl acetal resin in the second and third layers. The interlayer film for laminated glass according to claim 13, wherein the interlayer film is more than part by weight. Each of the polyvinyl acetal resins contained in the first to third layers includes a polyvinyl butyral resin,
The intermediate for laminated glasses according to any one of claims 8 to 14, wherein each of the plasticizers contained in the first to third layers contains triethylene glycol di-2-ethylhexanoate. film. First and second laminated glass components;
An intermediate film sandwiched between the first and second laminated glass constituent members,
Laminated glass, wherein the interlayer film is the interlayer film for laminated glass according to any one of claims 1 to 15.

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