JP5230905B2 - Intermediate film for laminated glass, laminated glass using the same, and method for producing the same - Google Patents

Description

  The present invention relates to an interlayer film for laminated glass used for laminated glass including film tempered glass excellent in impact resistance, penetration resistance, crime prevention, and the like used for automobiles, railway vehicles, buildings, showcases, and the like. It is related with glass and its manufacturing method.

  Generally, laminated glass having a structure in which a transparent adhesive layer (intermediate film) is sandwiched between glass plates is used for glass used for automobiles, particularly windshields. The transparent adhesive layer is formed of, for example, a PVB film, an EVA film, or the like, and the presence of the transparent adhesive layer improves the penetration resistance of the laminated glass. In addition, broken glass fragments remain attached to the transparent adhesive layer in response to an impact from the outside, thus preventing scattering. For this reason, for example, even if a laminated glass of an automobile is broken for the purpose of theft or intrusion, the window cannot be opened freely, so that it is useful as a security glass. Such a laminated glass is described in Patent Document 1, for example.

  On the other hand, for example, automobile door glass and fitted glass are generally less likely to be destroyed in an accident, and therefore do not require the penetration resistance or the like of the windshield, so a slightly reinforced low-strength glass. A board is used. However, when only such a single glass plate is used, there are the following drawbacks. That is, (1) Inferior to laminated glass in terms of impact resistance, penetration resistance, etc. (2) If broken for the purpose of theft or intrusion, it breaks into many pieces and the window is opened freely And so on. For this reason, it is also considered to use glass having characteristics such as laminated glass for the door glass and the fitted glass. As glass suitable for such applications, film tempered glass in which a glass plate and a plastic film are bonded via a transparent adhesive layer is described in Patent Documents 2 and 3, for example.

  Such a laminated glass two-sheet glass or an interlayer film for laminated glass (transparent adhesive layer) for bonding a glass plate of a film tempered glass and a plastic film, as described above, has excellent adhesion and resistance. Penetration is required. In particular, high performance is required for laminated glass using two glass plates.

  However, a laminated glass using a PVB film as an interlayer film for laminated glass has good penetration resistance and impact resistance, but its moisture resistance is not sufficient, so transparency and adhesiveness may deteriorate due to long-term use. is there.

  On the other hand, a laminated glass using an EVA film can obtain excellent water resistance, adhesion and penetration resistance, but the transparency may not be sufficient.

  In Patent Document 4 (Japanese Patent Application Laid-Open No. 2004-50750), since it has excellent moisture resistance, transparency and adhesiveness can be maintained over a long period of time, and sound insulation, penetration resistance, and impact resistance are remarkably good. As a glass laminate, a glass having a first adhesive resin layer mainly composed of polyvinyl butyral resin and a second adhesive resin layer mainly composed of ethylene-vinyl acetate copolymer resin between substrates. Laminates have been proposed.

JP 2002-187746 A JP 2002-046217 A JP 2002-068785 A JP 2004-50750 A JP 2003-327455 A (described later)

  The laminated glass having the composite film including the PVB layer and the EVA layer described in Patent Document 4 is excellent in transparency, adhesiveness, penetration resistance, impact resistance, and the like. In addition, additives such as ultraviolet absorbers are usually added in order to improve light resistance and weather resistance. In Patent Document 4, a UV absorber is not added to the PVB layer, and a benzophenone-based compound is used for the EVA layer.

  As an ultraviolet absorber used for an interlayer film for laminated glass using a PVB layer, for example, in Patent Document 5 (Japanese Patent Laid-Open No. 2003-327455), a benzotriazole-based compound has been conventionally used. In order to improve the above-mentioned UV absorber, it is stated that malonic acid ester compounds and / or oxalic acid anilide compounds are suitable as the UV absorber.

  According to the study of the present inventor, in the PVB layer / EVA layer laminated interlayer film for laminated glass, when a commonly used benzotriazole UV absorber is used for the PVB layer, EVA is crosslinked at the time of EVA crosslinking. It was found that the layer was prone to yellowing. As a result of further studies, it was found that in the laminated system of PVB layer / EVA layer, such yellowing was remarkably improved by using a benzophenone-based compound as an ultraviolet absorber.

  Therefore, the present invention is excellent for transparency, adhesion, penetration resistance, impact resistance, light resistance, weather resistance, and laminated glass for laminated glass that hardly causes yellowing in the heating process of production. The object is to provide an interlayer film.

  In addition, the present invention provides a laminated glass of laminated glass that is excellent in transparency, adhesion, penetration resistance, impact resistance, light resistance, weather resistance, and hardly yellowing in the heating process of production. Its purpose is to provide.

  Furthermore, the present invention is a laminated glass of laminated glass that is excellent in transparency, adhesiveness, penetration resistance, impact resistance, light resistance and weather resistance, and hardly causes yellowing in the heating process of production. The object is to provide a manufacturing method.

The above purpose is
An intermediate for laminated glass comprising a laminate of a layer (PVB layer) containing a composition containing polyvinyl butyral) and a crosslinked layer (EVA layer) containing an ethylene / vinyl acetate copolymer containing an organic peroxide. A membrane,
The composition containing polyvinyl butyral contains a benzophenone compound as an ultraviolet absorber ,
The composition containing polyvinyl butyral and the composition containing the ethylene / vinyl acetate copolymer do not contain a benzotriazole compound as an ultraviolet absorber and do not contain an alkali or alkaline earth metal salt of a fatty acid. An interlayer film for laminated glass characterized by the above. ;
Is achieved.

Preferred embodiments of the interlayer film for laminated glass of the present invention are as follows.
(1) A layer of a composition containing at least one layer of polyvinyl butyral and a crosslinked layer of a composition containing an ethylene / vinyl acetate copolymer containing at least one layer of an organic peroxide are alternately laminated 3 It is a laminate having a structure of layers or more.
(2) A three-layer structure laminate in which a crosslinked layer of an ethylene / vinyl acetate copolymer containing an organic peroxide is laminated on the other surface of the layer of the composition containing polyvinyl butyral. When sandwiched between two glass plates, the EVA layer having excellent adhesion to glass is in contact with the glass surface, so that the adhesion of laminated glass is significantly improved. Thereby, prevention of glass scattering when a laminated glass is destroyed can be improved markedly .
( 3 ) The composition containing the said ethylene / vinyl acetate copolymer contains the benzophenone series compound as a ultraviolet absorber.
( 4 ) A benzophenone compound is represented by the following formula (I):

[However, R ¹ represents a hydroxyl group, R ² represents a hydrogen atom or a hydroxyl group, R ³ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 14 carbon atoms, or 1 to 1 carbon atom. 14 alkoxy groups are represented, and R ⁴ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 14 carbon atoms, or an alkoxy group having 1 to 14 carbon atoms. ]
It is a compound represented by these.
( 5 ) The vinyl acetate unit of the ethylene / vinyl acetate copolymer is in the range of 23 to 38% by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer. Excellent transparency.
( 6 ) The melt flow index (MFR) of the ethylene / vinyl acetate copolymer is 1.5 to 30.0 g / 10 min. Pre-crimping becomes easy.
(7) a composition comprising a polyvinyl butyral, a benzophenone compound, 0.01 to 3.0 parts by weight per 100 parts by weight of polyvinyl butyral (preferably 0.1 to 2.0 parts by weight) containing .
(8) ethylene / vinyl acetate copolymer, an organic peroxide, 0.05 to 5.0 part by weight of the vinyl ethylene / acetate copolymer 100 parts by weight (preferably 0.5 to 3.0 Part by mass).

  The present invention also provides a laminated glass characterized in that the interlayer film for laminated glass described above is sandwiched between two transparent substrates and bonded and integrated.

  In the laminated glass, it is preferable that the two transparent substrates are both glass plates, and that one of the two transparent substrates is a glass plate and the other is a plastic film.

  Further, the laminated glass is characterized in that the laminated glass is sandwiched between two transparent substrates and passed through a nip roll, laminated and pressure-bonded, and then heat-crosslinked. This method can be advantageously obtained by the production method.

  In the said manufacturing method, it is preferable that the temperature of a nip roll is 70-130 degreeC. Moreover, in the said manufacturing method, it is not necessary to perform the de-method of a heating / pressurization process (namely, autoclave process), before passing a nip roll, Therefore It is preferable not to perform a heating / pressurization process.

  The interlayer film for laminated glass of the present invention is a laminate including a laminate structure of EVA layer / PVB layer excellent in transparency, penetration resistance, impact resistance and the like, and is a benzophenone-based UV absorber for the PVB layer A compound is used, so that yellowing hardly occurs during production and use. That is, according to the study of the present inventor, in such a laminate, when a benzotriazole-based UV absorber generally used for the PVB layer is used, the EVA layer is easily yellowed during EVA crosslinking. It has been clarified that the use of benzophenone compounds significantly improves such yellowing. Therefore, the interlayer film for laminated glass of the present invention can be produced under heating conditions capable of crosslinking EVA without using an autoclave despite the inclusion of the PVB layer, and is yellowed as described above. Has gained almost no improved transparency. Therefore, it can be said that the intermediate film for glass of the present invention is a highly transparent intermediate film that includes a laminated structure of a PVB layer and an EVA layer having various characteristics and is free from yellowing.

  Similarly, the laminated glass obtained using this interlayer film is not yellowed, and has excellent transparency, adhesion, penetration resistance and impact resistance.

  The interlayer film for laminated glass of the present invention comprises a layer of a composition containing polyvinyl butyral (PVB layer), a cross-linked layer (EVA layer) of a composition containing an ethylene / vinyl acetate copolymer containing an organic peroxide, and It has the basic composition including the laminated body. The PVB layer contains a benzophenone-based compound as an ultraviolet absorber, thereby improving the yellowing of the EVA layer particularly at the time of EVA cross-linking.

  The interlayer film for laminated glass of the present invention and the laminated glass of the present invention will be described in detail below with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of an embodiment of a laminated glass having an interlayer film for laminated glass of the present invention. A laminated glass 10 of FIG. 1 is obtained by bonding and integrating two glass plates 11A and 11B with an interlayer film 12 for laminated glass. The interlayer film 12 for laminated glass is a two-layer laminated film in which an EVA layer 13 and a PVB layer 14 are laminated, and the glass plate 11A and the EVA layer 13 and the glass plate 11B and the PVB layer 14 are in contact with each other. Since the interlayer film 12 for laminated glass is laminated with the PVB layer 14 having good transparency, penetration resistance and impact resistance, and the EVA layer 13 for compensating for its defects (moisture resistance, adhesiveness), It is an intermediate film with the advantages of both and excellent properties. The EVA layer 13 is a layer in which EVA is crosslinked. Furthermore, in the interlayer film 12 for laminated glass of the present invention, the PVB layer 14 contains a benzophenone-based compound as an ultraviolet absorber, and thereby yellowing of the EVA layer particularly during the crosslinking of EVA is improved in each stage. Yes. Therefore, it can be said that the interlayer film 12 for laminated glass has the above characteristics and hardly yellows.

  FIG. 2 is a cross-sectional view showing an example of a preferred embodiment of a laminated glass having the interlayer film for laminated glass of the present invention. The laminated glass 20 of FIG. 2 is obtained by bonding and integrating two glass plates 21A and 21B with an interlayer film 22 for laminated glass. The interlayer film 22 for laminated glass is a three-layer laminated film in which an EVA layer 23A, a PVB layer 24, and an EVA layer 23B are laminated in this order, and the EVA layers 23A and 23B are formed on both the glass plate 21A and the glass plate 21B. Each is in contact. Since both of the glass plates 21A and 21B are in contact with the EVA layers 23A and 23B, the adhesion and water resistance between the glass plates 21A and 21B and the intermediate film 22 are greatly improved. Is greatly suppressed and durability is also improved.

  FIG. 3 is a cross-sectional view showing an example of a preferred embodiment of a laminated glass having the interlayer film for laminated glass of the present invention. A laminated glass 30 in FIG. 3 is obtained by bonding and integrating two glass plates 31A and 31B with an interlayer film 32 for laminated glass. The interlayer film 32 for laminated glass is a three-layer laminated film in which a PVB layer 34A, an EVA layer 33, and a PVB layer 34B are laminated in this order. The PVB layer 34A and the PVB layer 34B are laminated on both the glass plate 31A and the glass plate 31B. Are touching each other. For this reason, the laminated glass which transparency improved especially is obtained.

  1 to 3, one of the glass plates may be a transparent plastic film. In that case, it may be called film tempered glass. Moreover, although the example of 2 layer structure and 3 layer structure was shown as an intermediate film for laminated glasses, as long as at least 1 layer of EVA layer and PVB layer is used, respectively, a structure of 4 layers or more may be used.

  The laminated glass of the present invention can be designed to have appropriate performance in terms of impact resistance, penetration resistance, transparency, etc. when one of the glass plates is plastic film (film reinforced glass). For example, it can be used for glass such as window glass provided in various vehicle bodies and buildings, or glass such as showcases and show windows. Both glass plates can be designed to exhibit particularly excellent impact resistance and improved penetration resistance, and can be used for various applications including laminated glass.

  The glass plate used in the present invention is usually silicate glass. In the case of film tempered glass, the glass plate thickness varies depending on the place where it is installed. For example, when it is used for a side glass and a fitted glass of an automobile, it is not necessary to make it thick like a windshield, generally 0.1 to 10 mm, and preferably 0.3 to 5 mm. The one glass plate 1 is reinforced chemically or thermally.

  In the case of a laminated glass that is both a glass plate suitable for an automobile windshield or the like, the thickness of the glass plate is generally 0.5 to 10 mm, and preferably 1 to 8 mm.

  The interlayer film for laminated glass of the present invention is a film having at least one EVA layer and PVB layer as described above.

  The PVB resin composition constituting the PVB layer generally contains a PVB resin, a plasticizer, an ultraviolet absorber, and the like. As the PVB resin, those having a polyvinyl acetal unit of 70 to 95% by weight, a polyvinyl acetate unit of 1 to 15% by weight and an average degree of polymerization of 200 to 3000, particularly 300 to 2500 are preferred.

  The PVB resin composition of the present invention contains a benzophenone compound as an ultraviolet absorber (UV absorber). As the benzophenone compound, in the present invention, the following formula (I):

[However, R ¹ represents a hydroxyl group, R ² represents a hydrogen atom or a hydroxyl group, R ³ represents a hydrogen atom, a hydroxyl group, an alkyl having 1 to 14 carbon atoms (particularly 1 to 8 carbon atoms). Represents a group or an alkoxy group having 1 to 14 carbon atoms (especially 1 to 8 carbon atoms), and R ⁴ is a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 14 carbon atoms (especially 1 to 8 carbon atoms). Alternatively, it represents an alkoxy group having 1 to 14 carbon atoms (particularly 1 to 8 carbon atoms). ]
It is preferable that it is a compound represented by these.

R ¹ represents a hydroxyl group, R ² represents a hydrogen atom or a hydroxyl group, R ³ represents a hydrogen atom, a hydroxyl group, an octyl group or a methoxy group, and R ⁴ represents a hydrogen atom, a hydroxyl group, Or it preferably represents a methoxy group. In particular, both R ¹ and R ² are preferably hydroxyl groups.

  Preferred examples of the benzophenone compounds include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2-hydroxy-4-n-octylbenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, particularly 2-hydroxy-4-n-octylbenzophenone, 2,2'-dihydroxy- 4,4′-dimethoxybenzophenone is preferred.

  In the PVB layer, the benzophenone-based compound is 0.0 to 3.0 parts by mass (preferably 0.01 to 3.0 parts by mass, particularly 0.1 to 2.0 parts by mass) with respect to 100 parts by mass of PVB. It is preferable to use it.

  Furthermore, if necessary, other ultraviolet absorbers (eg, triazine compounds, benzoate compounds, and hindered amine compounds) may be used in an amount less than the same amount as the benzophenone compounds. However, when an ultraviolet absorber of a benzotriazole-based compound is included, the EVA layer is easily yellowed during EVA crosslinking, and thus cannot be used in the present invention. A benzotriazole-based compound is an ultraviolet absorber having a benzotriazole ring.

  Examples of the benzotriazole compounds include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole and 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole. 2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-amylphenyl) benzotriazole Etc.

Further PVB resin composition, have name contains the alkali or alkaline earth metal salt of a fatty acid (generally used as adhesion regulator). In general, it is an alkaline earth metal salt of a fatty acid (generally a fatty acid having 1 to 12 carbon atoms), in particular magnesium octylate. Use of such an adhesive force regulator may form a chelate complex with a benzophenone compound, and the combined use of both may cause yellowing of the layer.

  Examples of alkaline earth metal salts of the fatty acids include magnesium formate, magnesium acetate, magnesium lactate, magnesium stearate, magnesium octylate, calcium formate, calcium acetate, calcium lactate, calcium stearate, calcium octylate, barium formate, acetic acid Barium, barium lactate, barium stearate, barium octylate, etc .; examples of alkali metal salts of fatty acids include potassium formate, potassium acetate, potassium lactate, potassium stearate, potassium octylate, sodium formate, sodium acetate, sodium lactate , Sodium stearate, sodium octylate and the like.

  Examples of the plasticizer for the PVB resin composition include organic plasticizers such as monobasic acid esters and polybasic acid esters, and phosphoric acid plasticizers.

  Monobasic acid esters include organic acids such as butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptanoic acid, n-octylic acid, 2-ethylhexylic acid, pelargonic acid (n-nonylic acid), decylic acid, and tris. Esters obtained by reaction with ethylene glycol are preferred, in particular triethylene-di-2-ethylbutyrate, triethylene glycol-di-2-ethylhexoate, triethylene glycol-di-capronate, triethylene glycol- Di-n-octoate is preferred. An ester of the above organic acid with tetraethylene glycol or tripropylene glycol can also be used.

  As the polybasic acid ester plasticizer, for example, an ester of an organic acid such as adipic acid, sebacic acid or azelaic acid and a linear or branched alcohol having 4 to 8 carbon atoms is preferable, and in particular, dibutyl seba Kate, dioctyl azelate and dibutyl carbitol adipate are preferred.

  As the phosphoric acid plasticizer, tributoxyethyl phosphate, isodecylphenyl phosphate, triisopropyl phosphate and the like are preferable.

  In the PVB resin composition, if the amount of the plasticizer is small, the film formability is deteriorated, and if it is too large, the durability during heat resistance is impaired. Therefore, the plasticizer is generally added in an amount of 5 to 50 with respect to 100 parts by mass of the polyvinyl butyral resin. It is preferable to include 10 parts by mass, particularly 10 to 40 parts by mass.

  Additives such as stabilizers and antioxidants may be added to the PVB resin composition to further prevent deterioration.

  In the laminate of the present invention, if the thickness of the PVB layer is too thin, sufficient impact resistance and penetration resistance cannot be obtained, and if it is too thick, the laminate becomes thick and the transparency is also lowered. From 0.05 to 5 mm, particularly 0.4 to 1.2 mm is preferable.

  EVA used for the EVA resin composition constituting the EVA layer generally has a vinyl acetate content of 23 to 38% by mass, more preferably 23 to 38% by mass, and particularly preferably 23 to 28% by mass. When the vinyl acetate content is less than 23% by mass, the transparency of the resin obtained when crosslinked and cured at a high temperature is not sufficient. Conversely, when the vinyl acetate content exceeds 38% by mass, the impact resistance when a security glass is obtained. The penetration resistance tends to be insufficient. Moreover, it is preferable that the melt flow index (MFR) of EVA is 4.0-30.0 g / 10min, especially 8.0-18.0g / 10min. Pre-crimping becomes easy.

  The EVA resin composition contains an organic peroxide and an ultraviolet absorber in the EVA, and may further contain various additives such as a crosslinking aid, an adhesion improver, and a plasticizer as necessary. it can.

  As the ultraviolet absorber, it is preferable to use the benzophenone-based compound used in the PVB layer. In the EVA layer, the benzophenone-based compound is 0.0 to 5.0 parts by mass (preferably 0.05 to 5.0 parts by mass, particularly 0.5 to 3.0 parts by mass) with respect to 100 parts by mass of EVA. It is preferable to use it.

  Furthermore, if necessary, other ultraviolet absorbers (eg, triazine compounds, benzoate compounds, and hindered amine compounds) may be used in an amount less than the same amount as the benzophenone compounds. However, when a benzotriazole-based ultraviolet absorber is used, the EVA layer is easily yellowed during EVA crosslinking, and therefore cannot be used in the present invention.

  The EVA resin composition usually does not contain an alkaline earth metal salt of a fatty acid (generally used as an adhesion modifier) that is usually contained in the PVB resin composition. Use of such an adhesive force regulator may form a chelate complex with a benzophenone compound, and the combined use of both may cause yellowing of the layer.

  In the present invention, any organic peroxide can be used in combination as long as it decomposes at a temperature of 100 ° C. or higher to generate radicals. The organic peroxide is generally selected in consideration of the film formation temperature, the adjustment conditions of the composition, the curing (bonding) temperature, the heat resistance of the adherend, and the storage stability. In particular, the one having a decomposition temperature of 70 ° C. or more with a half-life of 10 hours is preferable.

  Examples of this organic peroxide include 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane-3-di- t-butyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide, α, α′-bis (t-butylperoxy) Isopropyl) benzene, n-butyl-4,4-bis (t-butylperoxy) valerate, 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) -3 , 3,5-trimethylcyclohexane, t-butyl peroxybenzoate, benzoyl peroxide, t-butyl peroxyacetate, methyl ethyl ketone pero Oxide, 2,5-dimethylhexyl-2,5-bisperoxybenzoate, butyl hydroperoxide, p-menthane hydroperoxide, p-chlorobenzoyl peroxide, hydroxyheptyl peroxide, chlorohexanone peroxide, octanoyl peroxide Oxide, decanoyl peroxide, lauroyl peroxide, cumyl peroxy octoate, succinic acid peroxide, acetyl peroxide, m-toluoyl peroxide, t-butyl peroxyisobutylene and 2,4-dichlorobenzoyl peroxide Can be mentioned.

  The EVA layer is used to improve or adjust various physical properties of the film (optical properties such as mechanical strength, adhesiveness, transparency, heat resistance, light resistance, crosslinking speed, etc.), and in particular to improve mechanical strength. It preferably contains a group-containing compound, a methacryloxy group-containing compound and / or an epoxy group-containing compound.

  The acryloxy group-containing compound and methacryloxy group-containing compound to be used are generally acrylic acid or methacrylic acid derivatives, and examples thereof include acrylic acid or methacrylic acid esters and amides. Examples of ester residues include linear alkyl groups such as methyl, ethyl, dodecyl, stearyl, lauryl, cyclohexyl group, tetrahydrofurfuryl group, aminoethyl group, 2-hydroxyethyl group, 3-hydroxypropyl group. Group, 3-chloro-2-hydroxypropyl group. In addition, polyhydric alcohols such as ethylene glycol, triethylene glycol, polypropylene glycol, polyethylene glycol, trimethylolpropane, and pentaerythritol, and esters of acrylic acid or methacrylic acid can also be used.

  Examples of amides include diacetone acrylamide.

  Examples of polyfunctional compounds (crosslinking aids) include esters obtained by esterifying a plurality of acrylic acid or methacrylic acid with glycerin, trimethylolpropane, pentaerythritol, etc., and allyl compounds such as triallyl cyanurate and triallyl isocyanurate. be able to.

Examples of epoxy-containing compounds include triglycidyl tris (2-hydroxyethyl) isocyanurate, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and phenol. (Ethyleneoxy) ₅ glycidyl ether, pt-butylphenyl glycidyl ether, adipic acid diglycidyl ester, phthalic acid diglycidyl ester, glycidyl methacrylate, butyl glycidyl ether can be mentioned.

  In the present invention, a silane coupling agent can be added as an adhesion improver in order to further enhance the adhesive force between the EVA layer and the glass plate or plastic film.

  Examples of this silane coupling agent include γ-chloropropylmethoxysilane, vinylethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltri Methoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N- Mention may be made of β- (aminoethyl) -γ-aminopropyltrimethoxysilane. These silane coupling agents may be used alone or in combination of two or more. Moreover, it is preferable that content of the said compound is 5 mass parts or less with respect to 100 mass parts of EVA.

  The plasticizer is not particularly limited, but polybasic acid esters and polyhydric alcohol esters are generally used. Examples thereof include dioctyl phthalate, dihexyl adipate, triethylene glycol-di-2-ethylbutyrate, butyl sebacate, tetraethylene glycol diheptanoate, and triethylene glycol dipelargonate. One type of plasticizer may be used, or two or more types may be used in combination. The content of the plasticizer is preferably in the range of 5 parts by mass or less with respect to 100 parts by mass of EVA.

  Further, if the thickness of the EVA layer is too thin, sufficient moisture resistance and sound insulation cannot be obtained, and if it is too thick, the laminate becomes thick and the transparency is lowered. It is preferable to be 2 to 1.2 mm.

  The EVA layer of the present invention is produced, for example, by a method of obtaining a layered product by molding a composition containing the above-mentioned EVA, organic peroxide, ultraviolet absorber, etc. by ordinary extrusion molding, calendar molding (calendering) or the like. can do. In the same manner as described above, the PVB layer of the present invention is formed by, for example, a method of obtaining a layered product by molding a composition containing PVB, an ultraviolet absorber, etc. by ordinary extrusion molding, calendar molding (calendering), or the like. Can be manufactured.

  Alternatively, a layered product can be obtained by dissolving the above composition in a solvent and coating the solution on a suitable support with a suitable coating machine (coater) and drying to form a coating film.

  The PVB layer and the EVA layer may be formed using respective resin films, or may be formed by using a PVB / EVA composite resin film by two-layer extrusion molding of PVB resin and EVA resin or the like. Moreover, the other resin composition is applied to any one of the resin films, for example, the EVA resin composition is applied to a PVB resin film formed in advance to form a two-layer laminated film. You may do it. A three-layer laminated film for bonding can be formed in the same manner.

  In order to produce the laminated glass of the present invention, first, a PVB resin film and an EVA resin film are formed, and a necessary number of PVB resin films and EVA resin films are laminated and interposed between glass plates. After degassing, it may be bonded and integrated by pressing under heating. Such a laminate can be obtained, for example, by a vacuum bag method or a nip roll method. Such lamination can be performed by pressure bonding by a nip roll method because the EVA layer is soft, and the production of the laminate becomes easy. It is preferable that the temperature of a nip roll is 70-130 degreeC. Further, in such a lamination (particularly in the case of an EVA layer / PVB layer / EVA layer configuration), since a residual air is reduced, a de-method (heating / pressurizing treatment by an autoclave) can be omitted.

  When the laminated glass (laminated body) is produced, the EVA layer is generally crosslinked at 100 to 150 ° C. (particularly around 130 ° C.) for 10 minutes to 1 hour. Such cross-linking is carried out at the temperature of 80 to 120 ° C., for example, at 100 to 150 ° C. (especially around 130 ° C.) after degassing while being sandwiched between the glass plates when the laminate is produced. The heat treatment is performed for 10 minutes to 1 hour. Cooling after crosslinking is generally performed at room temperature, and in particular, the faster the cooling, the better.

  As described above, one glass plate of the laminated glass of the present invention may be a film tempered glass as a plastic film, and the plastic film used in that case is a polyethylene terephthalate (PET) film or a polyethylene aphthalate (PEN) film. And polyethylene butyrate film, and PET film is preferred.

  When the hard coat layer is formed on the surface of the plastic film, an ultraviolet curable resin or a thermosetting resin is used as the resin used for that purpose. The hard coat layer generally has a thickness of 1 to 50 μm, preferably 3 to 20 μm.

  As the ultraviolet curable resin, a known ultraviolet curable resin can be used, and any other low molecular weight and multifunctional resin suitable for hard coat treatment is not particularly limited. Examples of the ultraviolet curable resin include urethane oligomers having a plurality of ethylenic double bonds, oligomers such as polyester oligomers and epoxy oligomers, pentaerythritol tetraacrylate (PETA), pentaerythritol tetramethacrylate, and dipentaerythritol hexaacrylate (DPEHA). The monofunctional or polyfunctional oligomers and the like are generally composed of a reactive diluent and a photopolymerization initiator. Furthermore, various additives can be contained. As the reactive diluent, the acryloxy group-containing compound, methacryloxy group-containing compound and / or epoxy group-containing compound used in the transparent adhesive layer can be used, and the transparent adhesive layer can also be used as a photopolymerization initiator. The compounds used in can be used.

  One kind of each of the oligomer, the reactive diluent and the initiator may be used, or two or more kinds thereof may be used in combination. As for content of a reactive diluent, 0.1-10 mass parts is common with respect to 100 mass parts of ultraviolet curable resin, and 0.5-5 mass parts is preferable. The content of the photopolymerization initiator is preferably 5 parts by mass or less with respect to 100 parts by mass of the ultraviolet curable resin.

  As the thermosetting resin, a reactive acrylic resin, a melamine resin, an epoxy resin, or the like can be used. The ultraviolet curable resin can also be used.

  When a hard coat layer is formed using an ultraviolet curable resin, the ultraviolet curable resin is diluted as it is or with an organic solvent to an appropriate concentration, and the resulting solution is applied to an appropriate film with an appropriate coating machine (coater). After coating on top and drying as necessary, a hard coat layer can be formed by irradiating with UV light for several seconds to several minutes directly or through a release sheet (after vacuum degassing) with a UV lamp. As the UV lamp, a high pressure mercury lamp, a medium pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, or the like can be used.

  When a hard coat layer is formed using a thermosetting resin, an organic solvent solution of the thermosetting resin is applied onto an appropriate film with an appropriate coating machine (coater), and a release sheet is provided if necessary, a laminator, etc. After degassing, heat curing and thermocompression bonding are performed. In the case where the release sheet is not used, it is preferable to dry for 60 seconds before heating and pressure bonding to evaporate the solvent of the coating layer and to prevent the surface from sticking. Even when a release sheet is used, it is preferable that the release sheet is provided after slightly drying.

  You may provide the transparent conductive layer which consists of a metal and / or a metal oxide in the surface of the glass plate of the laminated glass obtained by this invention.

  A barrier layer may be formed on the side surface of the laminated glass obtained as described above. In general, the thickness of the barrier layer is preferably 0.1 to 20 μm and 1 to 10 μm.

  The laminated glass thus obtained can be used for the following applications. In other words, glass fitted in automobiles, side glass and rear glass, railway vehicles such as ordinary vehicles, express vehicles, express vehicles and sleeper vehicles, door windows for passenger doors, window glasses and indoor door glasses, windows in buildings, etc. Glass and indoor door glass, indoor display showcases and show windows. Preferably, it is useful for automobile side or rear glass, railcar window glass, especially automobile door glass.

  The following examples further illustrate the present invention.

[Example 1]
PVB and EVA sheets (thickness 400 μm) were obtained by a calendar molding method using the following blend as a raw material. The kneading of the blend was carried out at 80 ° C. for 15 minutes, the calender roll temperature was 80 ° C., and the processing speed was 5 m / min.
(Formulation for PVB sheet formation (parts by mass))
PVB resin (degree of acetalization 66 mol%): 100
Plasticizer (triethylene glycol-di (2-ethylbutyrate)): 33
UV adsorbent (2,2′-dihydroxy-4,4′-dimethoxybenzophenone): 0.15
(Formulation for EVA sheet formation (parts by mass))
EVA resin (vinyl acetate content 26% by weight): 100
Cross-linking agent (1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane): 2.0
Silane coupling agent (γ-methacryloxypropyltrimethoxysilane): 0.5
Crosslinking aid (triallyl isocyanurate): 2.0
UV adsorbent (2,2′-dihydroxy-4,4′-dimethoxybenzophenone): 0.15
As the glass plate, two silicate glass plates having a thickness of 5 mm that had been washed and dried in advance were prepared.

  Two glass plates were laminated via the laminate of the EVA sheet / PVB sheet / EVA sheet obtained above, and pre-pressed at a temperature of 110 ° C. using a nip roll. Next, this pre-pressed glass is put in an oven, heat-treated for 30 minutes at a temperature of 130 ° C., and then cooled so that the ambient temperature decreases at 20 ° C./minute, and a laminated glass (see FIG. 2) is obtained. Manufactured.

[Reference Example 1]
In Example 1, a laminated glass was produced in the same manner except that 0.001 part by mass of magnesium octylate (adhesive strength adjusting agent) was added to the formulation for forming the PVB sheet.

[Reference Example 2]
In Example 1, in the formulation for forming an EVA sheet, 2- (3′-t-butyl-2′-hydroxy-5 ′) was used instead of 2,2′-dihydroxy-4,4′-dimethoxybenzophenone as an ultraviolet adsorbent. A laminated glass was produced in the same manner except that the same amount of -methylphenyl) -5-chlorobenzotriazole was used.

[Reference Example 3]
In Example 1, in the formulation for forming the PVB sheet, 2- (3′-t-butyl-2′-hydroxy-5 ′) was used instead of 2,2′-dihydroxy-4,4′-dimethoxybenzophenone as the UV adsorbent. A laminated glass was produced in the same manner except that the same amount of -methylphenyl) -5-chlorobenzotriazole was used.

[Evaluation of laminated glass]
(1) Yellowing After the obtained laminated glass was allowed to stand for 1000 hours in an environment according to JIS-C-8917 (temperature irradiation at 63 ° C., relative humidity 53% and 1000 W / m ² UV irradiation), yellowing by UV irradiation In order to investigate the degree of change, the difference between the YI values before and after being left (ΔYI value) was determined. An SM color computer (manufactured by Suga Test Instruments Co., Ltd.) was used for measuring the ΔYI value.
(2) Ultraviolet Absorbance The transmittance of the obtained laminated glass at 380 nm was measured using a spectrophotometer (U-4000, manufactured by Hitachi, Ltd.).

  The measurement results are shown below.

  As is clear from the above results, the laminated glass obtained in Example 1 according to the present invention is excellent in yellowing and ultraviolet absorption, and can be said to be a laminated glass having high transparency and excellent durability. The reference example has large yellowing and cannot be said to be sufficiently excellent in transparency.

FIG. 1 shows an example of an embodiment of a laminated glass of the present invention. FIG. 2 shows an example of a preferred embodiment of the laminated glass of the present invention. FIG. 3 shows an example of the embodiment of the laminated glass of the present invention.

Explanation of symbols

10, 20, 30 Laminated glass 11A, 11B, 21A, 21B, 31A, 31B Glass plate 12, 22, 32 Interlayer film for laminated glass EVA layer 13, 23A, 23B, 33
PVB layer 14, 24, 34A, 34B

Claims (15)

An interlayer film for laminated glass comprising a laminate of a composition layer containing polyvinyl butyral and a crosslinked layer of a composition containing an ethylene / vinyl acetate copolymer containing an organic peroxide,
The composition containing polyvinyl butyral contains a benzophenone compound as an ultraviolet absorber ,
The composition containing polyvinyl butyral and the composition containing the ethylene / vinyl acetate copolymer do not contain a benzotriazole compound as an ultraviolet absorber and do not contain an alkali or alkaline earth metal salt of a fatty acid. An interlayer film for laminated glass characterized by the above.   A structure of three or more layers in which a layer of a composition containing at least one polyvinyl butyral and a cross-linked layer of a composition containing an ethylene / vinyl acetate copolymer containing at least one organic peroxide are alternately laminated The interlayer film for laminated glass according to claim 1, wherein the interlayer film has a laminated body.   2. A three-layer structure laminate in which a crosslinked layer of a composition containing an ethylene / vinyl acetate copolymer containing an organic peroxide is laminated on the other surface of a layer of a composition containing polyvinyl butyral. 2. The interlayer film for laminated glass according to 2. The interlayer film for laminated glass according to any one of claims 1 to 3 , wherein the composition containing the ethylene / vinyl acetate copolymer contains a benzophenone-based compound as an ultraviolet absorber. A benzophenone compound is represented by the following formula (I):

[However, R ¹ represents a hydroxyl group, R ² represents a hydrogen atom or a hydroxyl group, R ³ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 14 carbon atoms, or 1 to 1 carbon atom. 14 alkoxy groups are represented, and R ⁴ represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 14 carbon atoms, or an alkoxy group having 1 to 14 carbon atoms. The interlayer film for laminated glass according to any one of claims 1 to 4 , wherein the interlayer film is a compound represented by the formula: The vinyl acetate unit of the ethylene / vinyl acetate copolymer is in the range of 23 to 38% by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer, for laminated glass according to any one of claims 1 to 5 . Interlayer film. The interlayer film for laminated glass according to any one of claims 1 to 6 , wherein the ethylene / vinyl acetate copolymer has a melt flow index (MFR) of 1.5 to 30.0 g / 10 minutes. The composition containing polyvinyl butyral contains 0.01 to 3.0 parts by mass of the benzophenone-based compound with respect to 100 parts by mass of polyvinyl butyral, for laminated glass according to any one of claims 1 to 7 . Interlayer film. Ethylene / vinyl acetate copolymer, an organic peroxide, any of claims 1-8 containing from 0.05 to 5.0 part by weight of the ethylene / vinyl acetate copolymer 100 parts by mass 1 The interlayer film for laminated glass according to Item. A laminated glass, wherein the interlayer film for laminated glass according to any one of claims 1 to 9 is sandwiched between two transparent substrates and bonded and integrated. The laminated glass according to claim 10 , wherein the two transparent substrates are both glass plates. The laminated glass according to claim 10 , wherein one of the two transparent substrates is a glass plate and the other is a plastic film. The interlayer film for laminated glass according to any one of claims 1 to 9 is sandwiched between two transparent substrates, passed through a nip roll, laminated and pressure-bonded, and then heat-crosslinked. A method for producing laminated glass.

The method for producing a laminated glass according to claim 13 , wherein the temperature of the nip roll is 70 to 130 ° C. The manufacturing method of the laminated glass of Claim 13 or 14 which does not perform a heating and pressurizing process before letting a nip roll pass.

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