WO2020067083A1

WO2020067083A1 - Multilayer film

Info

Publication number: WO2020067083A1
Application number: PCT/JP2019/037440
Authority: WO
Inventors: 鷹行河野; 浩孝保田; 磯上　宏一郎; 利之井口
Original assignee: 株式会社クラレ
Priority date: 2018-09-26
Filing date: 2019-09-25
Publication date: 2020-04-02
Also published as: JPWO2020067083A1

Abstract

The present invention relates to a multilayer film which comprises at least a polyvinyl acetal resin layer (A) and a thermoplastic resin layer (B), and which is configured such that: the viscosity of a 10 mass% toluene/ethanol solution (wherein the toluene/ethanol mass ratio is 1/1) of the polyvinyl acetal resin in the layer (A) as measured at 20°C at 30 rpm with use of a Blookfield type (B type) viscometer is more than 200 mPa·s; the amount of a plasticizer in the layer (A) is 0-35% by mass relative to the total mass of the layer (A); the layer (A) has a thickness of 10-350 μm; and the tensile storage elastic modulus E'(40) at 40°C and the tensile storage elastic modulus E'(100) at 100°C of the resin material that constitutes the layer (B) satisfy formula (1) and formula (2). (1): E'(40) ≥ 1,000 MPa (2): E'(100) ≥ 10 MPa

Description

Laminated film

<< The present invention relates to a laminated film having at least a polyvinyl acetal resin layer (A) and a thermoplastic resin layer (B).

For laminated glass for architectural purposes, laminated glass for surface protection of displays or windshields or side glasses for automobiles, a resin layer is placed between two inorganic or organic glasses for the purpose of preventing scattering when the glass is broken. Safety glass is mainly used. In recent years, such safety glass has been increasingly provided with further functionality (for example, heat ray shielding property, design property, conductivity, light reflection property or light absorption property). As the method, it has the above-mentioned functions on a thin polyethylene phthalate (hereinafter referred to as “PET”) film or a polycarbonate film (hereinafter referred to as “PET film etc.”) which is excellent in versatility or economy. A method is known in which a functional layer is formed by printing, thermocompression bonding, vapor deposition, or the like, and the obtained film with a functional layer is used as an interlayer film for laminated glass. For example, Patent Documents 1 to 3 disclose such methods. It is described that a transparent laminated glass having no appearance defects such as wrinkles could be produced by a suitable method.

On the other hand, 3D shape laminated glass, which has been increasingly used in recent years, is required to be able to follow the 3D shape. However, a general PET film or the like has poor followability to a 3D shape due to characteristics of a resin or a film forming method, and is likely to have wrinkles or cuts in a functional layer on the PET film or the like at the time of manufacturing a laminated glass. . In view of this problem, an interlayer film for laminated glass using a PET film or the like having improved moldability has been studied. For example, in Patent Document 4, a plastic film is sandwiched between two resin interlayer films. A laminated glass produced using a film, wherein the plastic film has a specific heat shrinkage, a specific elastic modulus or a specific elongation, and is selected from a plastic film such as a PET film or a polycarbonate film. Laminated glass is described. Patent Document 5 discloses a polyester film for laminated glass having at least three layers and having a specific haze, wherein both outermost polyester films have a specific thickness, a specific composition, and a specific haze. Polyester films are described.

JP 2009-35439 A JP 2009-35440 A JP-A-6-915 JP 2010-180089 A JP 2014-180844 A

The problem to be solved by the invention is to provide a laminated glass with a function or the like, when distorting the functional layer or deteriorating the transparency of the laminated glass as occurs when using PET or a general interlayer film. An object of the present invention is to provide a laminated film which can be suppressed and can be easily used for a laminated glass having a 3D shape which is required to conform to a shape.

The present inventors have studied the laminated film in detail in order to solve the above problems, and have completed the present invention.
That is, the present invention includes the following preferred embodiments.
[1] A laminated film having at least a polyvinyl acetal resin layer (A) and a thermoplastic resin layer (B), using a Brookfield type (B type) viscometer for the polyvinyl acetal resin in the layer (A). The viscosity of a 10% by mass toluene / ethanol = 1/1 (mass ratio) solution measured at 20 ° C. and 30 rpm is greater than 200 mPa · s, and the amount of plasticizer in the layer (A) is )), The layer (A) has a thickness of 10 to 350 μm, and the resin material constituting the layer (B) has a tensile storage modulus E ′ (40) at 40 ° C. And a tensile storage modulus E ′ (100) at 100 ° C. satisfying the formulas (1) and (2).
(1) E '(40) ≧ 1000 MPa
(2) E '(100) ≧ 10 MPa
[2] The refractive index difference between the refractive index of the layer (A) and the refractive index of the layer (B) measured based on ASTM D542 is 0.10 or less, and the laminated film is sandwiched between two glasses. The laminated film according to the above [1], wherein the laminated glass has a haze value based on JIS K7136 of 1.5% or less.
[3] The laminated film according to [1] or [2], wherein the thickness of the layer (B) is 150 μm or less.
[4] The laminated film according to any one of the above [1] to [3], wherein the resin material constituting the layer (B) has a tensile storage modulus at 120 ° C. E ′ (120) satisfying the expression (3).
(3) E ′ (120) ≦ 500 MPa
[5] The laminated film according to any of [1] to [4], wherein the arithmetic average roughness (Ra) of at least one surface of the layer (B) is 0.15 μm or less.
[6] The laminated film according to any one of [1] to [5], wherein the layer (B) contains metal oxide fine particles having a heat ray shielding function.
[7] The laminated film according to any one of [1] to [6], further comprising another polyvinyl acetal resin layer (C).
[8] The laminated film according to any one of [1] to [7], further comprising a functional layer (D).
[9] The laminated film according to [8], wherein the layer (D) is a heat ray shielding coating layer having a thickness of 0.01 to 200 μm.
[10] The laminated film according to the above [8] or [9], wherein the layer (D) is a conductive structure.
[11] The laminated film according to [10], wherein the conductive structure is formed by a printing method, an etching method, or an evaporation method.
[12] The laminated film according to [10] or [11], wherein the conductive structure contains at least one conductive material selected from the group consisting of gold, silver, copper, and a metal oxide.
[13] The laminated film according to any of [1] to [12], wherein the layer (A) contains metal oxide fine particles having a heat ray shielding function.
[14] A laminated film with a protective film, comprising a peelable protective film on the outermost layer of the laminated film according to any of [1] to [13].
[15] The laminated film according to any one of [1] to [13] or the laminated film obtained by peeling the protective film from the laminated film with a protective film according to [14], between a pair of glasses. Laminated glass sandwiched.

According to the present invention, when imparting functionality or the like to the laminated glass, it is possible to suppress distortion of the functional layer or deterioration in the transparency of the laminated glass as occurs when using PET or a general interlayer, It is possible to provide a laminated film which can be easily used for laminated glass having a 3D shape which requires conformability to a shape.

It is a schematic diagram of the laminated glass used for measurement of a heat creep resistance value. It is a schematic diagram of the laminated glass used for measurement of the heat creep resistance value to which the iron plate was adhered. FIG. 3 is a schematic view showing a state where a laminated glass to which an iron plate is adhered is fixed at a predetermined angle in order to measure a heat creep resistance value. It is a mimetic diagram showing one mode of 3D shape laminated glass concerning the present invention.

The present invention relates to a laminated film having at least a polyvinyl acetal resin layer (A) and a thermoplastic resin layer (B), and a Brookfield type (B type) viscometer for the polyvinyl acetal resin in the layer (A). The viscosity of a 10% by mass toluene / ethanol = 1/1 (mass ratio) solution measured at 20 ° C. and 30 rpm was greater than 200 mPa · s, and the amount of plasticizer in layer (A) was 0 to 35% by mass based on the total mass of A), the thickness of the layer (A) is 10 to 350 μm, and the resin material constituting the layer (B) has a tensile storage modulus at 40 ° C. E ′ ( 40) and the tensile storage modulus E ′ (100) at 100 ° C. are calculated by the formulas (1) and (2):
(1) E '(40) ≧ 1000 MPa
(2) E '(100) ≧ 10 MPa
A laminated film that satisfies is satisfied.

[Polyvinyl acetal resin layer (A)]
The laminated film of the present invention has one or more polyvinyl acetal resin layers (A). When the laminated film of the present invention has a plurality of layers (A), the resin materials constituting the layer (A) may be the same or different. In the present invention, the term “resin material” means a material made of a resin or a mixture containing a resin (that is, a resin composition).

層 The layer (A) in the laminated film of the present invention contains a polyvinyl acetal resin as a resin component. The content of the polyvinyl acetal resin in the layer (A) is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 65% by mass or more, based on the total mass of the layer (A). Is 70% by mass or more. The upper limit of the content is not particularly limited. The content is 100% by mass or less based on the total mass of the layer (A).

The layer (A) may have a multi-component phase-separated structure, but the phase-separated structure preferably has an average particle size of the island component of less than 100 nm, more preferably less than 80 nm, and It is particularly preferred not to exhibit the phase separation structure of By not exhibiting the phase separation structure of the sea-island or exhibiting a sufficiently small particle size, transparency that can be used for a windshield of a car or the like can be ensured.

The polyvinyl acetal resin contained in the layer (A) in the present invention is one polyvinyl acetal resin, or has a viscosity average polymerization degree, an acetalization degree, a vinyl acetate unit content, a vinyl alcohol unit content, and an ethylene unit content. And two or more polyvinyl acetal resins each differing in at least one of the molecular weight and the chain length of the aldehyde used for acetalization. When the layer (A) contains two or more different polyvinyl acetal resins, another polyvinyl acetal resin layer (C) or a functional layer (D), which will be described later, at the time of melt-molding ease and at the time of producing laminated glass. Polyvinyl acetal resin is a mixture of at least two polyvinyl acetal resins having different viscosity-average polymerization degrees, or at least two having different viscosity-average polymerization degrees, from the viewpoint of easily preventing distortion of glass and displacement of glass when using laminated glass. It is preferably an acetalized product of a mixture of two polyvinyl alcohol-based resins.

The degree of acetalization of the polyvinyl acetal resin used in the present invention is preferably at least 40 mol%, more preferably at least 45 mol%, further preferably at least 50 mol%, still more preferably at least 60 mol%, particularly preferably at least 68 mol%. Mol% or more, preferably 86 mol% or less, more preferably 84 mol% or less, still more preferably 82 mol% or less. The degree of acetalization is defined as a unit consisting of two carbon atoms in the main chain (eg, a vinyl alcohol unit, a vinyl acetate unit, an ethylene unit, etc.) in a polyvinyl alcohol-based resin which is a raw material for producing a polyvinyl acetal resin. The amount of the above units forming an acetal, based on one repeating unit. When the acetalization degree is in the range between the lower limit and the upper limit described above, the mechanical strength of the obtained layer (A) tends to be sufficient, and the compatibility between the polyvinyl acetal resin and the plasticizer is good. It is preferable because it easily becomes. When the layer (A) contains two or more different polyvinyl acetal resins, it is preferable that the degree of acetalization of at least one polyvinyl acetal resin is in the range between the lower limit and the upper limit described above. The degree of acetalization of the polyvinyl acetal resin is preferably at least 65 mol% from the viewpoint of water resistance. The degree of acetalization can be adjusted by adjusting the amount of aldehyde used in the acetalization reaction.

The vinyl acetate unit content of the polyvinyl acetal resin is preferably at least 0.1 mol%, more preferably at least 0.3 mol%, preferably at most 30 mol%, more preferably at most 20 mol%, Preferably it is 0.5 to 3 mol% or 5 to 8 mol%. The content of the vinyl acetate unit is such that a unit composed of two carbon atoms in the main chain (for example, a vinyl alcohol unit, a vinyl acetate unit, an ethylene unit, etc.) in a polyvinyl alcohol-based resin which is a raw material for producing a polyvinyl acetal resin is a repeating unit. And the amount of vinyl acetate units based on one repeating unit. The vinyl acetate unit content can affect the polarity of the polyvinyl acetal resin, which can change the plasticizer compatibility or mechanical strength of layer (A). When the vinyl acetate unit content is in the range between the lower limit and the upper limit, good bonding with another polyvinyl acetal resin layer (C) which may be optionally laminated may be easily achieved, and Reduction of optical distortion and the like are easily achieved. When the layer (A) contains two or more different polyvinyl acetal resins, the vinyl acetate unit content of at least one polyvinyl acetal resin is preferably within the above range. The content of the vinyl acetate unit can be adjusted by appropriately adjusting the degree of saponification of the raw material polyvinyl alcohol-based resin.

The vinyl alcohol unit content of the polyvinyl acetal resin is preferably 9 to 36 mol%, more preferably 18 to 34 mol%, further preferably 22 to 34 mol%, still more preferably 26 to 34 mol%, and particularly preferably. It is 26 to 31 mol%, particularly preferably 26 to 30 mol%. The vinyl alcohol unit content is defined as a unit composed of two carbon atoms in the main chain (for example, a vinyl alcohol unit, a vinyl acetate unit, an ethylene unit, etc.) in a polyvinyl alcohol-based resin, which is a raw material for producing a polyvinyl acetal resin, as one repeating unit. , Is the amount of vinyl alcohol units based on one repeating unit. When the vinyl alcohol unit content is within the above range, the difference in the refractive index between the layer (C) and the adjacently laminated layer (C) may be reduced in some cases, and a laminated glass with less optical unevenness is easily obtained. On the other hand, the content of the vinyl alcohol unit is preferably 9 to 29 mol%, more preferably 12 to 26 mol%, further preferably 15 to 23 mol%, and particularly preferably 16 to 20 mol% in order to further impart the sound insulation performance. Mol%. When the layer (A) includes two or more different polyvinyl acetal resins, the vinyl alcohol unit content of at least one polyvinyl acetal resin is preferably within the above range. The vinyl alcohol unit content can be adjusted within the above range by adjusting the amount of aldehyde used in the acetalization reaction.

The polyvinyl acetal resin is usually composed of an acetal-forming unit, a vinyl alcohol unit and a vinyl acetate unit, and the amount of each of these units can be determined by, for example, JIS K6728 "Testing method for polyvinyl butyral" or nuclear magnetic resonance (NMR). Measured.

The viscosity of a 10% by mass toluene / ethanol = 1/1 (mass ratio) solution of a polyvinyl acetal resin measured at 20 ° C. and 30 rpm using a Brookfield type (B type) viscometer has a viscosity of 200 mPa · s. Greater than. When the viscosity is 200 mPa · s or less, the distortion of the functional layer (D) cannot be sufficiently suppressed during the production of the laminated glass, and the displacement of the obtained laminated glass at a high temperature is sufficiently suppressed. Can not do.
In the case where the plasticizer shifts from the layer (C) which may be optionally used during the production of a laminated glass to the layer (A), the viscosity is preferably at least 220 mPa · s, more preferably at least 230 mPa · s, even more preferably. Is at least 240 mPa · s, particularly preferably at least 265 mPa · s. When the plasticizer does not migrate from the layer (C), which may be used in some cases, to the layer (A) during the production of the laminated glass, for example, when a barrier layer is present between the layers, the viscosity is preferably 220 mPa · s. The above is more preferably 230 mPa · s or more, and still more preferably 240 mPa · s or more. When the viscosity of the polyvinyl acetal resin is equal to or more than the lower limit, distortion and cracking of the layer (C) or the layer (D) are easily suppressed during the production of the laminated glass, and the resulting laminated glass is misaligned at a high temperature. Is easily prevented.

When the amount of the plasticizer in the layer (A) is 0 to 10% by mass with respect to the total mass of the layer (A), the viscosity is adjusted so that good film-forming properties can be easily obtained, and From the viewpoint of ease of production, it is usually 1500 mPa · s or less, preferably 1000 mPa · s or less, more preferably 800 mPa · s or less, still more preferably 500 mPa or less, and particularly preferably 450 mPa or less.
When the amount of the plasticizer in the layer (A) is from 10 to 35% by mass based on the total mass of the layer (A), the viscosity is preferably such that good film-forming properties can be easily obtained, and From the viewpoint of ease of production, it is usually 3000 mPa · s or less, preferably 2000 mPa · s or less, more preferably 1500 mPa · s or less.

The viscosity can be adjusted by using or using a polyvinyl acetal resin produced using a polyvinyl alcohol-based resin having a high viscosity average degree of polymerization as a raw material or a part of the raw material. When the polyvinyl acetal resin used to form the layer (A) comprises a mixture of a plurality of resins, the viscosity is the viscosity of such a mixture.

The peak top molecular weight of the polyvinyl acetal resin is preferably 115,000 to 200,000, more preferably 120,000 to 160,000, and particularly preferably 130,000 to 150,000. When the peak top molecular weight of the polyvinyl acetal resin is within the above range, suitable film-forming properties and suitable film physical properties (for example, suitability for lamination, creep resistance and elongation at break) are easily obtained. The peak top molecular weight of the polyvinyl acetal resin can be adjusted within the above range by using or using a polyvinyl acetal resin produced using a polyvinyl alcohol resin having a high viscosity average polymerization degree as a raw material or a part of the raw material.
The molecular weight distribution of the polyvinyl acetal resin in the layer (A), that is, the ratio (Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) is preferably 2.7 or more, more preferably 2.8. Above, particularly preferably 2.9 or more. When the molecular weight distribution of the polyvinyl acetal resin is equal to or more than the lower limit, it is easy to achieve both film forming properties and suitable film properties (for example, suitability for lamination, creep resistance and breaking strength). By acetalizing a mixture of polyvinyl alcohol-based resins having different viscosity average polymerization degrees, or by mixing acetalized products of polyvinyl alcohol-based resins having different viscosity average polymerization degrees, the molecular weight distribution of the polyvinyl acetal resin is not less than the lower limit. Can be adjusted. The upper limit of the molecular weight distribution is not particularly limited. From the viewpoint of easy film formation, the molecular weight distribution is usually 10 or less, preferably 5 or less.
When the layer (A) includes two or more different polyvinyl acetal resins, the peak top molecular weight and the molecular weight distribution of at least one polyvinyl acetal resin are preferably within the above ranges.
The peak top molecular weight and the molecular weight distribution are determined by gel permeation chromatography (GPC) using polystyrene having a known molecular weight as a standard.

The polyvinyl acetal resin can be produced by a conventionally known method, typically, by acetalizing a polyvinyl alcohol-based resin (for example, polyvinyl alcohol resin or ethylene vinyl alcohol copolymer) with an aldehyde. Specifically, for example, a polyvinyl alcohol-based resin is dissolved in warm water, and the obtained aqueous solution is kept at a predetermined temperature (for example, 0 ° C. or higher, preferably 10 ° C. or higher, for example, 90 ° C. or lower, preferably 20 ° C. or lower). Then, the required acid catalyst and aldehyde are added, and the acetalization reaction proceeds with stirring. Next, the reaction temperature is raised to about 70 ° C. to ripen the reaction, thereby completing the reaction. Thereafter, neutralization, washing and drying are performed to obtain a powder of a polyvinyl acetal resin.

The polyvinyl acetal resin used in the present invention is preferably one produced by the reaction of at least one polyvinyl alcohol-based resin with one or more aliphatic unbranched aldehyde having 2 to 10 carbon atoms. . As such an aldehyde, n-butyraldehyde is preferable from the viewpoint that a polyvinyl acetal resin having a suitable breaking energy is easily obtained. The content of n-butyraldehyde in the aldehyde used for acetalization is preferably 50% by mass or more, more preferably 80% by mass or more, still more preferably 95% by mass or more, particularly preferably 99% by mass or more. % By mass.

Accordingly, in one preferred embodiment of the present invention, the polyvinyl acetal resin is a polyvinyl butyral resin. As the polyvinyl butyral resin, a modified polyvinyl butyral resin obtained by butyralizing a polyvinyl alcohol-based polymer obtained by saponifying a copolymer of a vinyl ester and another monomer with butyraldehyde can be used. Examples of the other monomer include ethylene and propylene. Further, as the other monomer, a monomer having a hydroxyl group, a carboxyl group or a carboxylate group can be used.

The polyvinyl alcohol-based resin used for producing the polyvinyl acetal resin may be a single resin or a mixture of polyvinyl alcohol-based resins having different viscosity average polymerization degrees or hydrolysis degrees.

The viscosity average polymerization degree of the polyvinyl alcohol-based resin as a raw material of the polyvinyl acetal resin is preferably 100 or more, more preferably 300 or more, still more preferably 400 or more, still more preferably 600 or more, particularly preferably 700 or more, and particularly more preferably. Is 750 or more. When the viscosity average polymerization degree of the polyvinyl alcohol-based resin is equal to or more than the lower limit, distortion and disconnection of the layer (C) or the layer (D) are easily suppressed at the time of producing a laminated glass, and the glass is produced by heat in the obtained laminated glass. The deviation phenomenon is easily prevented. Further, the viscosity average polymerization degree of the polyvinyl alcohol-based resin is preferably 5,000 or less, more preferably 3,000 or less, further preferably 2,500 or less, particularly preferably 2300 or less, particularly preferably 2,000 or less. When the viscosity average polymerization degree of the polyvinyl alcohol-based resin is equal to or less than the upper limit, good film-forming properties are easily obtained.

The preferable value of the viscosity average degree of polymerization of the polyvinyl acetal resin is the same as the preferable value of the viscosity average degree of polymerization of the polyvinyl alcohol-based resin. When the layer (A) contains two or more different polyvinyl acetal resins, it is preferable that the viscosity average polymerization degree of at least one polyvinyl acetal resin is not less than the lower limit and not more than the upper limit.

ポリビニル In order to set the vinyl acetate unit of the obtained polyvinyl acetal resin to preferably 30 mol% or less, it is preferable to use a polyvinyl alcohol resin having a saponification degree of 70 mol% or more. When the saponification degree of the polyvinyl alcohol-based resin is equal to or more than the lower limit, the transparency and heat resistance of the resin tend to be excellent, and the reactivity with the aldehyde also becomes good. The saponification degree is more preferably 95 mol% or more.

粘度 The viscosity average degree of polymerization and the degree of saponification of the polyvinyl alcohol-based resin can be measured based on JIS K 6726 “Testing method for polyvinyl alcohol”.

The layer (A) preferably contains an uncrosslinked polyvinyl acetal from the viewpoint of easily obtaining good film-forming properties. It is also possible that layer (A) comprises a cross-linked polyvinyl acetal. Methods for cross-linking polyvinyl acetal are described, for example, in EP 1527107B1 and WO 2004/063231 A1 (thermal self-crosslinking of carboxyl group-containing polyvinyl acetal), EP 1606325 A1 (polyvinyl acetal cross-linked by polyaldehyde), and WO 2003/2003. 020776 @ A1 (polyvinyl acetal crosslinked with glyoxylic acid). It is also a useful method to control the amount of intermolecular acetal bonds generated or to control the degree of blocking of the remaining hydroxyl groups by appropriately adjusting the acetalization reaction conditions.

The thickness of the layer (A) is 10 to 350 μm. The thickness is preferably 20 μm or more, more preferably 30 μm or more, preferably 330 μm or less, more preferably 295 μm or less, even more preferably 270 μm or less, even more preferably 250 μm or less, particularly preferably 150 μm or less, particularly more preferably Preferably it is 120 μm or less, particularly preferably less than 100 μm. When the thickness of the layer (A) is equal to or more than the lower limit, the problem that distortion or the like occurs in the layer (C) or the layer (D) due to shrinkage or deformation of the layer (A) is less likely to occur, and good production is achieved. Easy to obtain film properties. In addition, when the thickness of the layer (A) is equal to or less than the upper limit, the problem that the impact resistance of the vehicle glass using the layer (A) is reduced is less likely to occur. This is because the transfer amount of the plasticizer from the layer (C) which is optionally laminated on the layer (A) can be suppressed to a small range. The thickness of the layer (A) can be measured using a thickness gauge, a laser microscope, or the like. When the laminated film of the present invention has a plurality of layers (A), the thickness of each layer (A) is preferably within the above range.

The tensile storage modulus E ′ (40) at 40 ° C. of the resin material constituting the layer (A) is preferably less than 1000 MPa, or the tensile storage modulus E at 100 ° C. of the resin material constituting the layer (A). '(100) is preferably less than 10 MPa.

<Plasticizer>
In the present invention, the amount of the plasticizer in the layer (A) is 0 to 35% by mass based on the total mass of the layer (A). When the amount of the plasticizer is more than 35% by mass, it is difficult to form the layer (A), and it is particularly difficult to keep the shrinkage rate at the time of heating low. D) easily causes distortion and / or cracking.
The amount of the plasticizer is preferably 0 to 33% by mass, more preferably 0 to 30% by mass. When the amount of the plasticizer in the layer (A) is within the above range, the layer (A) excellent in film-forming property and handleability is easily produced, and the layer (A) is produced when a laminated glass using the layer (A) is produced. D) Distortion and cracking are easily suppressed.

When a plasticizer is contained in the layer (A), one or more compounds selected from the following group are preferably used as the plasticizer.
Esters of polyvalent aliphatic or aromatic acids. For example, dialkyl adipates (eg, dihexyl adipate, di-2-ethylbutyl adipate, dioctyl adipate, di-2-ethylhexyl adipate, hexyl cyclohexyl adipate, diheptyl adipate, dinonyl adipate, diisononyl adipate, heptyl nonyl adipate); adipic acid Of an alcohol containing an alcohol or an ether compound [eg, di (butoxyethyl) adipate, di (butoxyethoxyethyl) adipate]; dialkyl sebacate (eg, dibutyl sebacate); sebacic acid and an alicyclic or ether compound Esters of phthalic acid (eg, butylbenzyl phthalate, bis-2-butoxyethyl phthalate); and cycloaliphatic polyvalent carboxy Acid and esters of aliphatic alcohols (e.g., 1,2-cyclohexane dicarboxylic acid diisononyl esters).
Esters or ethers of polyhydric aliphatic or aromatic alcohols or oligoether glycols having one or more aliphatic or aromatic substituents. Examples thereof include esters of glycerin, diglycol, triglycol, tetraglycol and the like with a linear or branched aliphatic or alicyclic carboxylic acid, and at least one terminal of an oligoalkylene glycol having 2 to 10 repeating units. Is a compound having an ether bond or an ester bond to a group having 2 to 14 carbon atoms, or an oligocarboxylic acid compound having 2 to 14 carbon atoms and an alcohol compound having 2 to 14 carbon atoms which may contain an ether bond. Ester compounds of the formula (I). Specifically, diethylene glycol-bis- (2-ethylhexanoate), triethylene glycol-bis- (2-ethylhexanoate) (hereinafter sometimes referred to as “3GO”), triethylene glycol- Bis- (2-ethylbutanoate), tetraethylene glycol-bis- (2-ethylhexanoate), tetraethylene glycol-bis-n-heptanoate, triethylene glycol-bis-n-heptanoate, triethylene glycol- Bis-n-hexanoate, tetraethylene glycol dimethyl ether, and dipropylene glycol dibenzoate.
Phosphoric acid esters of aliphatic or aromatic alcohols; Examples include tris (2-ethylhexyl) phosphate, triethyl phosphate, diphenyl-2-ethylhexyl phosphate, and tricresyl phosphate.
Esters of citric, succinic and / or fumaric acid.

Further, a polyester or oligoester composed of a polyhydric alcohol and a polycarboxylic acid, a terminal ester or ether thereof, a polyester or oligoester composed of lactone or hydroxycarboxylic acid, or a terminal ester or ether thereof. It may be used as a plasticizer.

When the plasticizer is contained in the layer (A), a problem (for example, a problem such as a change in physical properties over time) caused by the migration of the plasticizer between the layer (A) and the layer (C) when laminated. ), From the viewpoint of easy suppression, the same plasticizer as that contained in the layer (C) to be laminated, or plasticity that does not impair the physical properties (eg, heat resistance, light resistance, transparency, and plasticizing effect) of the layer (C). It is preferred to use agents. From such a viewpoint, as the plasticizer, a compound in which at least one terminal of the oligoalkylene glycol having 2 to 10 repeating units is bonded to a group having 2 to 14 carbon atoms by an ether bond or an ester bond, or a compound having 2 to 10 carbon atoms An ester compound of an oligocarboxylic acid compound having 14 and an alcohol compound having 2 to 14 carbon atoms which may contain an ether bond is preferable. Among them, 3GO, triethylene glycol-bis (2-ethylbutanoate), tetraethylene glycol -Bis- (2-ethylhexanoate) and tetraethylene glycol-bis-n-heptanoate are more preferred, and triethylene glycol-bis- (2-ethylhexanoate) is particularly preferred.

The total amount of the polyvinyl acetal resin and the plasticizer contained in the layer (A) is not particularly limited, but is preferably 50% by mass or more, more preferably 80% by mass or more, and further preferably, based on the total mass of the layer (A). Is 90% by mass or more, even more preferably 95% by mass or more, particularly preferably 99% by mass or more, very preferably 99.5% by mass or more, and may be 100% by mass.

(Other additives)
In the layer (A), as a component other than the polyvinyl acetal resin and the plasticizer optionally contained, a heat-shielding material (for example, an inorganic heat-shielding fine particle or an organic heat-shielding material having an infrared absorbing ability), an ultraviolet absorber, Antioxidants, light stabilizers, adhesion regulators and / or various additives for regulating adhesion, antiblocking agents, pigments, dyes, and the like may be added as necessary.

<Ultraviolet absorber>
An ultraviolet absorber is a compound having the ability to absorb ultraviolet light. An ultraviolet absorber is a compound that is said to have a function of mainly converting light energy into heat energy. Examples of the ultraviolet absorber include benzophenones, benzotriazoles, triazines, benzoates, salicylates, cyanoacrylates, oxalic anilides, malonic esters, and formamidines. These can be used alone or in combination of two or more. Among the above, benzotriazoles, triazines, or ultraviolet absorbers having a maximum value ε _max of the molar extinction coefficient at a wavelength of 380 to 450 nm of 1200 dm ³ · mol ⁻¹ · cm ⁻¹ or less are preferable.

Benzotriazoles have a high effect of suppressing deterioration of optical properties such as coloring due to irradiation with ultraviolet rays. Examples of benzotriazoles include 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol (manufactured by BASF; trade name TINUVIN329), 2- (2H- Benzotriazol-2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol (manufactured by BASF; trade name TINUVIN234) and 2,2′-methylenebis [6- (2H-benzotriazole) -2-yl) -4-tert-octylphenol] (manufactured by ADEKA Corporation; LA-31) and the like.

An ultraviolet absorber having a maximum value ε _max of the molar extinction coefficient at a wavelength of 380 to 450 nm of 1200 dm ³ · mol ⁻¹ · cm ⁻¹ or less can suppress the yellow tint of the obtained laminated film. Examples of such an ultraviolet absorbent include 2-ethyl-2'-ethoxy-oxalanilide (manufactured by Clariant Japan; trade name: Sandueboa VSU).

ベンゾ Among the above-mentioned ultraviolet absorbers, benzotriazoles and the like are preferably used from the viewpoint that resin deterioration due to ultraviolet irradiation is suppressed.

い Further, when it is desired to efficiently absorb a wavelength near the wavelength of 380 nm, a triazine ultraviolet absorber is preferably used. Examples of such an ultraviolet absorber include 2,4,6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3,5-triazine (manufactured by ADEKA Corporation; LA-F70); And hydroxyphenyltriazine-based ultraviolet absorbers (manufactured by BASF; TINUVIN 477-D, TINUVIN 460, and TINUVIN 479) which are analogs thereof.

The maximum value ε _max of the molar extinction coefficient of the ultraviolet absorber is measured as follows. 10.00 mg of an ultraviolet absorber is added to 1 L of cyclohexane, and dissolved so that there is no undissolved matter by visual observation. This solution is poured into a 1 cm × 1 cm × 3 cm quartz glass cell, and the absorbance at a wavelength of 380 to 450 nm is measured using a U-3410 type spectrophotometer manufactured by Hitachi, Ltd. The maximum value ε _max of the molar extinction coefficient is calculated from the molecular weight (M _UV ) of the ultraviolet absorbent and the measured maximum absorbance (A _max ) according to the following equation.
ε _max = [A _max / (10 × 10 ⁻³ )] × M _UV

The areal density (g / m ² ) of the ultraviolet absorbent in the layer (A) is preferably 0.2 or more, more preferably 0.5 or more, particularly preferably 0.7 or more, and preferably 10.0 or less. , More preferably 5.0 or less, particularly preferably 3.0 or less. When the areal density (g / m ² ) of the ultraviolet absorbent in the layer (A) is in the range between the lower limit and the upper limit described above, when the laminated glass is used, a sufficient ultraviolet absorbing effect is easily exhibited, In addition, good haze, good weather resistance, or a reduced change in color difference is easily obtained.

The amount of the ultraviolet absorber added is preferably not less than 10 ppm, more preferably not less than 100 ppm, preferably not more than 50,000 ppm, more preferably not more than 10,000 ppm, based on the weight of the polyvinyl acetal resin contained in the layer (A). 000 ppm or less. If the amount is equal to or more than the lower limit, a sufficient effect is likely to be exhibited. Even if the amount of the UV absorber is more than 50,000 ppm, no remarkable effect can be expected.

<Antioxidant>
The antioxidant alone is effective in preventing the resin from being oxidized and degraded in the presence of oxygen. For example, a phosphorus antioxidant, a hindered phenol antioxidant, a thioether antioxidant and the like can be mentioned. As the antioxidant, an antioxidant containing a portion having a phosphorus-based antioxidant effect and a portion having a hindered phenol-based antioxidant effect in the same molecule can also be used. One or two or more of these antioxidants can be used. Above all, from the viewpoint of the effect of preventing deterioration of the optical properties due to coloring, a phosphorus-based antioxidant and a hindered phenol-based antioxidant are preferable, and the combined use of a phosphorus-based antioxidant and a hindered phenol-based antioxidant is more preferable. . When a phosphorus-based antioxidant and a hindered phenol-based antioxidant are used in combination, the mass ratio of the used amount of the phosphorus-based antioxidant to the used amount of the hindered phenol-based antioxidant (the amount of the phosphorus-based antioxidant (Used amount) / (Used amount of hindered phenolic antioxidant) is preferably 1/5 or more, more preferably 1/2 or more. Further, (the amount of the phosphorus-based antioxidant) / (the amount of the hindered phenol-based antioxidant) is preferably 2/1 or less, more preferably 1/1 or less.

Examples of the phosphorus-based antioxidant include 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite (manufactured by ADEKA Corporation; trade name: ADK STAB HP-10), tris (2,4-di-t-butyl) -Butylphenyl) phosphite (manufactured by BASF; trade name: IRGAFOS168); and 3,9-bis (2,6-di-tert-butyl-4-methylphenoxy) -2,4,8,10-tetraoxa-3 Preferred is 9-diphosphaspiro [5.5] undecane (manufactured by ADEKA Corporation; trade name: ADK STAB PEP-36).

Hindered phenolic antioxidants include pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (manufactured by BASF; trade name IRGANO01010) and octadecyl-3- (3,5-Di-tert-butyl-4-hydroxyphenyl) propionate (manufactured by BASF; trade name IRGANO01076) is preferred.

Examples of the antioxidant containing a portion having a phosphorus-based antioxidant effect and a portion having a hindered phenol-based antioxidant effect in the same molecule include 6- [3- (3-t-butyl-4-hydroxy). -5-methyl) propoxy] -2,4,8,10-tetra-t-butyldibenz [d, f] [1,3,2] -dioxasphosphepin (Sumitomo Chemical Co., Ltd .; trade name Sumilizer GP Is preferred.

The areal density of the antioxidant in the layer (A) is preferably 0.1 g / m ² or more, more preferably 0.2 g / m ² or more, particularly preferably 0.5 g / m ² or more, and preferably ² g / m ² or more. .5g / ^{m 2} or less, more preferably 1.5 g / ^{m 2} or less, particularly preferably 2.0 g / ^{m 2} or less. When the areal density of the antioxidant in the layer (A) is in the range between the lower limit and the upper limit described above, when the laminated glass is used, a sufficient antioxidant effect is easily exhibited, and good haze or It is easy to obtain a reduced color difference change.

The compounding amount of the antioxidant is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, usually 5 parts by mass or less, preferably 4 parts by mass or less based on 100 parts by mass of the polyvinyl acetal resin. , More preferably 3 parts by mass or less. When the amount of the antioxidant is not less than the lower limit, a sufficient antioxidant effect is easily obtained. Even if the amount of the antioxidant is more than 5 parts by mass, a remarkable improvement in effect cannot be expected.

<Light stabilizer>
A light stabilizer is a compound that is said to have a function of capturing radicals generated mainly by oxidation by light. Suitable light stabilizers include hindered amines such as compounds having a 2,2,6,6-tetraalkylpiperidine skeleton (manufactured by ADEKA Corporation; LA-52 and LA-57) (manufactured by BASF; TINUVIN622SF and TINUVIN770). Is mentioned.

Surface density of light stabilizers in the layer (A), preferably from 0.05 g / ^{m 2} or more, more preferably 0.5 g / ^{m 2} or more, preferably 70 g / ^{m 2} or less, more preferably 30 g / m ² or less.
The compounding amount of the light stabilizer is preferably at least 0.01 part by mass, more preferably at least 0.05 part by mass, usually at most 10 parts by mass, more preferably at most 5 parts by mass, based on 100 parts by mass of the polyvinyl acetal resin. Part or less. When the amount of the light stabilizer is equal to or more than the lower limit, a sufficient effect is easily obtained. Even if the amount of the light stabilizer is more than 10 parts by mass, a remarkable improvement in effect cannot be expected.

<Heat shielding material>
The heat shielding material has a function of absorbing at least a light ray in a near infrared wavelength region. Examples of suitable heat shielding materials include metal oxide fine particles having a heat ray shielding function, such as tin-doped indium oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, indium-doped zinc oxide, gallium-doped zinc oxide, and tungsten oxide. , Lanthanum hexaboride, cerium hexaboride, anhydrous zinc antimonate, copper sulfide and the like. These may be used alone or in combination of two or more. Among these, it is preferable to contain anhydrous zinc antimonate or tin-doped indium oxide from the viewpoints of performance, safety, raw material availability, price and the like.
In a preferred embodiment of the present invention, the layer (A) contains metal oxide fine particles having a heat ray shielding function.

When the layer (A) contains a heat-shielding material, the infrared-absorbing ability of the heat-shielding material is determined by the optical path length (m) when infrared light passes through the layer (A) and the concentration of the heat-shielding material in the layer (A). (G / m ³ ). Therefore, the infrared absorbing ability of the heat shielding material is proportional to the areal density (g / m ² ) of the heat shielding material in the layer (A).

When metal-doped tungsten oxide (for example, cesium-doped tungsten oxide) is used as the heat-shielding material in the layer (A), the surface density (g / m ² ) of the heat-shielding material is preferably 0.10 or more, more preferably 0 or more. .15 or more, particularly preferably 0.20 or more, preferably 1.00 or less, more preferably 0.70 or less, and particularly preferably 0.50 or less.

When tin-doped indium oxide is used as the heat-shielding material in the layer (A), the surface density (g / m ² ) of the heat-shielding material is preferably 0.50 or more, more preferably 1.00 or more, and still more preferably. It is at least 1.50, particularly preferably at least 2.25, most preferably at least 3.00, preferably at most 15.00, more preferably at most 10.50, particularly preferably at most 7.50.

When antimony-doped tin oxide is used as the heat shielding material in the layer (A), the surface density (g / m ² ) of the heat shielding material is preferably 1.00 or more, more preferably 1.50 or more, and particularly preferably. Is 2.00 or more, preferably 10.00 or less, more preferably 7.00 or less, and particularly preferably 5.00 or less.

When a phthalocyanine compound is used as the heat-shielding material in the layer (A), the surface density (g / m ² ) of the heat-shielding material is preferably 0.010 or more, more preferably 0.015 or more, and particularly preferably 0.1% or more. 020 or more, preferably 0.100 or less, more preferably 0.070 or less, particularly preferably 0.050 or less.

When aluminum-doped zinc oxide is used as the heat shield material in the layer (A), the surface density (g / m ² ) of the heat shield material is preferably 1.00 or more, more preferably 1.50 or more, and particularly preferably. It is 2.00 or more, preferably 10.00 or less, more preferably 7.00 or less, and particularly preferably 5.00 or less.

When zinc antimonate is used as the heat shielding material in the layer (A), the surface density (g / m ² ) of the heat shielding material is preferably 1.00 or more, more preferably 1.50 or more, and particularly preferably 2 or more. 0.000 or more, preferably 10.00 or less, more preferably 7.00 or less, particularly preferably 5.00 or less.

When lanthanum hexaboride is used as the heat shielding material in the layer (A), the surface density (g / m ² ) of the heat shielding material is preferably 0.02 or more, more preferably 0.03 or more, and particularly preferably. It is 0.04 or more, preferably 0.20 or less, more preferably 0.14 or less, and particularly preferably 0.10 or less.

When the surface density (g / m ² ) of each heat shielding material is in the range between the lower limit and the upper limit described above, a sufficient effect is likely to be exhibited when a laminated glass is used, and a favorable effect is obtained. It is easy to obtain haze, good weather resistance or a small change in color difference.

場合 When the layer (A) contains a heat shielding material, it is preferable that at least the layer (A) contains at least one ultraviolet absorber. Thereby, for example, when the layer (B) is an inner layer and the layer (A) is an outer layer, the thermoplastic resin of the layer (B) is protected from ultraviolet rays and the heat shielding property of the laminated film can be enhanced. .

Further, for example, when the laminated film of the present invention has a three-layer structure of layer (A) / layer (B) / layer (A), the layer (A) may be made to contain a heat-shielding material to form a layer. (A) Since infrared rays pass through the optical path length of the two layers, the heat shielding properties can be enhanced without impairing the visible light transmittance or haze of the laminated glass.

<Adhesive strength adjuster>
The layer (A) may contain an adhesive force adjuster and / or various additives for adjusting the adhesiveness, if necessary, in order to control the adhesiveness of the laminated film to glass or the like.

As various additives for adjusting the adhesiveness, those disclosed in WO 03/033583 can also be used, and alkali metal salts and alkaline earth metal salts are preferably used. , Sodium, magnesium and the like. Examples of the salt include organic acids such as carboxylic acids such as octanoic acid, hexanoic acid, butyric acid, acetic acid, and formic acid; and salts of inorganic acids such as hydrochloric acid and nitric acid.

The optimal amount of the adhesive force adjusting agent and / or the various additives for adjusting the adhesiveness varies depending on the additive used. However, the adhesive force of the obtained laminated film to glass is poor in a Pummel test (Pummeltest; International). It is generally preferable to adjust the amount to be 3 or more and 10 or less, especially when high penetration resistance is required. In the case where the property is required, it is preferable to adjust so as to be 7 or more and 10 or less. When a high glass scattering prevention property is required, it is also a useful method not to add an adhesion regulator.

[Production method of polyvinyl acetal resin layer (A)]
The method for producing the polyvinyl acetal resin layer (A) is not particularly limited. After blending the polyvinyl acetal resin, a predetermined amount of plasticizer in some cases, and other additives as necessary, and uniformly kneading the mixture, an extrusion method, a calendar method, a pressing method, a casting method, an inflation method, or the like. It can be manufactured using a known film forming method.

中でも Among the known film forming methods, a method of manufacturing a film using an extruder is suitably employed. The resin temperature during extrusion is preferably from 150 to 250 ° C, more preferably from 170 to 230 ° C. If the resin temperature is too high, the polyvinyl acetal resin will decompose and the content of volatile substances will increase. On the other hand, when the resin temperature is too low, the content of the volatile substance increases. In order to remove volatile substances efficiently, the volatile substances can be removed by reducing the pressure through the vent port of the extruder.

[Thermoplastic resin layer (B)]
The laminated film of the present invention has one or more thermoplastic resin layers (B) in addition to the polyvinyl acetal resin layer (A). By the combination of the layer (A) and the layer (B), the laminated film of the present invention has a performance of favorably preventing distortion of the functional layer (D) which may be optionally provided, excellent optical performance, and excellent performance. It can also have curved surface followability. The layer (B) may be arranged at any position on the laminated film. The layer (B) is preferably the layer (A) from the viewpoint that the distortion of the layer (D) or the deterioration of the transparency of the laminated glass can be suppressed, and a laminated glass having a 3D shape required to follow the shape is easily obtained. Are stacked adjacent to each other.

The type of the film constituting the layer (B) is not particularly limited as long as it satisfies the formula (1) “E ′ (40) ≧ 1000 MPa” and the formula (2) “E ′ (100) ≧ 10 MPa”. In addition to the system film, a polyvinyl alcohol (PVA) system film, a polyvinyl acetal resin film, an ionomer film, a polyacetal (POM) film, a polypropylene (PP) film, a PET film, and the like can be used. As the layer (B), an acrylic film, a polyvinyl acetal resin film, or a PET film is preferably used from the viewpoint of cost, long-term light resistance, transparency, or good workability when processing as a laminated glass. These films may be unstretched films or stretched films. Unless otherwise specified, film means unstretched film. The polyvinyl acetal resin film that can be used as the layer (B) is different from the polyvinyl acetal resin layer (A).

The layer (B) may be a single-layer film made of a single thermoplastic resin material, or may be a multilayer film in which layers made of a plurality of thermoplastic resin materials are laminated.

樹脂 The resin component contained in the layer (B) may be an alloy resin obtained by mixing different resins at the time of melt-kneading, or may be a single resin. That is, for example, a maleic acid-modified acrylic resin and an acrylic resin are used for the purpose of modifying the resin in order to improve the adhesiveness with the layer (A) or the layer (C) or the layer (D) which may be laminated as the case may be. A melt-kneaded alloy resin may be used, or a single maleic acid-modified acrylic resin may be used.

The tensile storage elastic modulus E 'can be measured by the method described in Examples described later.
A film in which the resin material constituting the layer (B) has a tensile storage modulus E ′ (40) at 40 ° C. and a tensile storage modulus E ′ (100) at 100 ° C. that satisfies the formulas (1) and (2) As a manufacturing method, for example, a method of using an acrylic resin composition containing elastic particles for the layer (B) can be mentioned. The elastic particles include a crosslinked elastic polymer in which at least one inner layer contains a crosslinked elastic polymer having an alkyl acrylate monomer unit having an alkyl group having 1 to 8 carbon atoms and / or a conjugated diene monomer unit. The polymer layer is preferred, and the outermost layer is preferably a thermoplastic polymer layer containing a thermoplastic polymer having an alkyl methacrylate monomer unit having an alkyl group having 1 to 8 carbon atoms.
As a method for producing a film satisfying the formulas (1) and (2), a layer (B2) in which a methacrylate polymer block (z2) is bonded to an acrylate polymer block (z1) is used. A method using an acrylic resin composition containing the copolymer (Z) and the methacrylic resin (M) is exemplified. In this case, the melt viscosity [η (Z)] of the block copolymer (Z) at 220 ° C. and a shear rate of 122 / sec is 75 to 1500 Pa · s, and the methacrylic resin (M) has a melt viscosity of 220 ° C. The ratio [η (M) / η (Z)] of the melt viscosity [η (M)] to the melt viscosity [η (Z)] at a speed of 122 / sec is preferably 1 to 20.

樹脂 The resin material constituting the layer (B) has a tensile storage modulus E ′ (40) at 40 ° C. of 1000 MPa or more, preferably 1100 MPa or more, more preferably 1200 MPa or more. If the tensile storage modulus E ′ (40) is less than 1000 MPa, the film will have insufficient rigidity in practical use, resulting in poor handling properties, and a functional layer provided on the layer (B) by a processing method such as printing or etching. In such a process, the process passability is deteriorated. The tensile storage modulus E '(40) is usually 10,000 MPa or less.

樹脂 The resin material constituting the layer (B) has a tensile storage modulus E ′ (100) at 100 ° C. of 10 MPa or more, preferably 30 MPa or more, more preferably 50 MPa or more. If the tensile storage modulus E '(100) is less than 10 MPa, the layer (B) undergoes heat sagging during processing into a laminated glass, causing distortion and breakage of the functional layer. The tensile storage modulus E '(100) is usually 10,000 MPa or less.

The tensile storage modulus E ′ (120) at 120 ° C. of the resin material constituting the layer (B) is preferably 500 MPa or less, more preferably 400 MPa or less, and particularly preferably 300 MPa or less. When the tensile storage modulus E ′ (120) is equal to or less than the above upper limit, the layer (B) becomes sufficiently soft when processed into a laminated glass, and it is easy to obtain the followability to the 3D-shaped glass. Wrinkles and cuts are less likely to occur. The tensile storage modulus E '(120) is usually 0.1 MPa or more.

The arithmetic average roughness (Ra) of at least one surface of the layer (B) and the layer (A) or at least one surface of the layer (B) before being laminated with the layer (C) or the layer (D) which is optionally laminated is preferably It is 0.15 μm or less, more preferably 0.12 μm or less, and particularly preferably 0.10 μm or less. When the arithmetic average roughness (Ra) is equal to or less than the upper limit, excellent transparency after processing into a laminated glass can be easily obtained, and an adjacent layer (particularly, a layer (D) optionally laminated) can be obtained. It is easy to obtain good bondability. As a method of making the arithmetic average roughness (Ra) equal to or less than the upper limit, for example, in a process of forming a film by a melt extrusion film forming method using a T-die, two sufficiently smooth cooling rolls are used. A nip film forming method for imparting a mirror surface by sandwiching a film discharged from a die, or a cast film forming a film discharged from a die onto a roll using a sufficiently smooth cooling roll. And the like. The arithmetic average roughness (Ra) can be measured using a laser microscope. The arithmetic average roughness (Ra) can be obtained as an average value of the individual arithmetic average roughness (Ra) measured at any five places on the film surface, and this value is expressed in μm. Specifically, it can be measured according to JIS B0601: 2001.

The thickness of the layer (B) is preferably at least 15 μm, more preferably at least 30 μm, preferably at most 150 μm, more preferably at most 100 μm, particularly preferably at most 75 μm. When the thickness of the layer (B) is equal to or more than the lower limit, a sufficient handling property of the film in practical use is easily obtained, and when the thickness of the layer (B) is equal to or less than the upper limit, 3D-shaped glass is obtained. It is easy to obtain excellent followability.
When using a coating or vapor deposition method, the thickness of the layer (B) is preferably 0.1 μm or more, more preferably 0.5 μm or more, preferably 150 μm or less, more preferably 100 μm or less, and particularly preferably 75 μm or less. It is as follows. When the thickness of the layer (B) is equal to or more than the lower limit, the coating stability in practical use is excellent, and when the thickness of the layer (B) is equal to or less than the upper limit, excellent follow-up to 3D glass is achieved. Easy to get the character.
When the laminated film of the present invention has a plurality of layers (B), the thickness of each layer (B) is preferably within the above range.

Any acrylic film can be used as long as it satisfies the above conditions. Preferably, an acrylic film formed of an acrylic resin composition containing elastic particles, more preferably acrylic obtained by mixing acrylic multilayer polymer particles (Y) and methacrylic resin (M) at an arbitrary ratio. An acrylic film formed of the resin composition (R1) is used. The acrylic resin composition (R1) may contain an optional additive.
An acrylic resin composition in which a block copolymer (Z) in which a methacrylate ester polymer block (z2) is bonded to an acrylate ester polymer block (z1) and a methacrylic resin (M) are mixed at an arbitrary ratio. An acrylic film formed by (R2) is also suitably used. The acrylic resin composition (R2) may contain an optional additive.

[Acrylic multilayer polymer particles (Y)]
As the acrylic multilayer structure polymer particles (Y) contained in the acrylic film, known particles can be used. From the viewpoint of impact resistance and the like, the acrylic multilayer polymer particles (Y) include at least one inner layer (inner layer than the outermost layer) having an alkyl group having 1 to 8 carbon atoms. A crosslinked elastic polymer layer containing a crosslinked elastic polymer having a monomer unit and / or a conjugated diene-based monomer unit, wherein the outermost layer has a monoalkyl methacrylate having an alkyl group having 1 to 8 carbon atoms. Acrylic multilayer polymer particles (Y), which are thermoplastic polymer layers containing a thermoplastic polymer having a body unit, are preferred.

The content of the resin component derived from the acrylic acid alkyl ester monomer unit having an alkyl group having 1 to 8 carbon atoms and the conjugated diene monomer unit is equal to the total amount of the crosslinked elastic polymer layer. It is preferably at least 50% by mass based on the mass. The crosslinked elastic polymer contained in the crosslinked elastic polymer layer has a monomer unit other than an alkyl acrylate monomer unit having an alkyl group having 1 to 8 carbon atoms and a conjugated diene-based monomer unit. It may be something. Further, the crosslinked elastic polymer layer may contain a polymer other than the crosslinked elastic polymer.

In the thermoplastic polymer layer, the resin component derived from the alkyl methacrylate monomer unit having an alkyl group having 1 to 8 carbon atoms is 50% by mass or more based on the total mass of the thermoplastic polymer layer. Is preferred. The thermoplastic polymer contained in the thermoplastic polymer layer may have a monomer unit other than the alkyl methacrylate monomer unit having an alkyl group having 1 to 8 carbon atoms. Further, the thermoplastic polymer layer may contain a polymer other than the thermoplastic polymer.

Acrylic multi-layer polymer particles (Y) are a so-called core / shell rubber in which one or more inner layers including at least one crosslinked elastic polymer layer are covered by an outermost thermoplastic polymer layer. Particles.
In the acrylic multilayer polymer particles (Y), the crosslinked elastic polymer layer constituting at least one inner layer excluding the outermost layer has a molecular chain of this layer and a molecular chain in an adjacent layer bonded by a graft bond. It is preferred that

Examples of the alkyl acrylate having an alkyl group having 1 to 8 carbon atoms used in the crosslinked elastic polymer layer include, for example, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and propyl acrylate And the like. Examples of the conjugated diene-based monomer used in the crosslinked elastic polymer layer include 1,3-butadiene and isoprene.

In the crosslinked elastic polymer layer, besides an alkyl acrylate having an alkyl group having 1 to 8 carbon atoms and / or a conjugated diene monomer, a vinyl monomer copolymerizable therewith may be used. . Examples of the copolymerizable vinyl monomer include a methacrylic acid ester, an aromatic vinyl compound, and a polyfunctional monomer.
In the present specification, the “polyfunctional monomer” is a monomer having two or more polymerizable functional groups.

From the viewpoint of the impact resistance and the like of the laminated glass produced using the laminated film of the present invention, the crosslinked elastic polymer layer contains an alkyl acrylate unit having an alkyl group having 1 to 8 carbon atoms and / or a conjugated diene-based unit. The content of the resin component derived from the monomer unit is preferably at least 60% by mass, more preferably at least 70% by mass, based on the total mass of the crosslinked elastic polymer layer.

In the acrylic multilayer polymer particles (Y), examples of the alkyl methacrylate having an alkyl group having 1 to 8 carbon atoms used in the outermost thermoplastic polymer layer include methyl methacrylate and ethyl methacrylate. , Propyl methacrylate, butyl methacrylate, and cyclohexyl methacrylate. From the viewpoint of the dispersibility of the acrylic multilayer polymer particles (Y), the content of the resin component derived from the alkyl methacrylate monomer unit in the thermoplastic polymer layer is determined by the total mass of the thermoplastic polymer layer. Is preferably 70% by mass or more, more preferably 80% by mass or more.

数 The number of layers of the acrylic multi-layer polymer particles (Y) is not particularly limited, but is two, three, or four or more. In terms of thermal stability and productivity, it is particularly preferable that the acrylic multilayer polymer particles (Y) have a three-layer structure.

The acrylic multilayer polymer particles (Y) include, from the central side, a methyl methacrylate unit, an alkyl acrylate unit having an alkyl group having 1 to 8 carbon atoms, and a polyfunctional monomer unit. A crosslinked elastic body including a first layer composed of a crosslinked resin layer, an alkyl acrylate unit having an alkyl group having 1 to 8 carbon atoms, a methyl methacrylate unit (optional component), and a polyfunctional monomer unit And a third layer (outermost layer) composed of a hard thermoplastic resin layer containing a methyl methacrylate unit and an alkyl acrylate unit having an alkyl group having 1 to 8 carbon atoms. Layered polymer particles (Y1) are preferred. The first crosslinked resin layer contains 30 to 99.99% by mass of methyl methacrylate units, 1 to 69.99% by mass of an alkyl acrylate unit having an alkyl group having 1 to 8 carbon atoms, and 0.1 to 99.99% by mass. It preferably contains from 0.1 to 2% by mass of a polyfunctional monomer unit. The second crosslinked elastic layer is composed of 70 to 99.9% by mass of an alkyl acrylate unit having an alkyl group having 1 to 8 carbon atoms and 0 to 29.9% by mass of a methyl methacrylate unit (optional component). ) And 0.1 to 5% by mass of a polyfunctional monomer unit. The third layer of the hard thermoplastic resin layer preferably contains 80 to 99% by mass of a methyl methacrylate unit and 1 to 20% by mass of an alkyl acrylate unit having an alkyl group having 1 to 8 carbon atoms. .

In the three-layer polymer particles (Y1), the ratio of each layer is not particularly limited, and the first layer is 5 to 40% by mass, the second layer is 20 to 55% by mass, and the third layer (the outermost layer). Is preferably 15 to 75% by mass.

The particle diameter of the acrylic multilayer polymer particles (Y) is not particularly limited, but is preferably 0.05 μm or more, more preferably 0.06 μm or more, and further preferably 0.07 μm or more. . The particle size of the acrylic multilayer polymer particles (Y) is preferably 0.25 μm or less, more preferably 0.20 μm or less, and even more preferably 0.15 μm or less. When the particle size of the acrylic multilayer structure polymer particles (Y) is less than 0.05 μm, the handleability of the acrylic multilayer structure polymer particles (Y) tends to decrease. When the particle diameter of the acrylic multi-layer polymer particles (Y) is larger than 0.25 μm, the interlayer film for laminated glass of the present invention is whitened when stress is applied, and the transmittance is easily reduced (that is, the transmittance is reduced). , Stress whitening resistance is deteriorated). Further, when the addition ratio of the multilayer polymer particles (Y) having a large particle diameter is large, the haze of the obtained laminated glass tends to increase. From the viewpoint of stress whitening resistance and haze, the particle diameter of the acrylic multilayer polymer particles (Y) is preferably 0.15 μm or less. The particle size of the acrylic multilayer structure polymer particles (Y) can be appropriately adjusted by, for example, changing the addition amount of a surfactant or the composition of a monomer when performing polymerization by an emulsion polymerization method. it can.

The acrylic multi-layered polymer particles (Y) are composed of a polymer having a refractive index in the range of 1.485 to 1.495 measured based on ASTM D542. It is preferable from the viewpoint of enhancing the properties.

重合 The polymerization method of the acrylic multilayer polymer particles (Y) is not particularly limited, and an emulsion polymerization method is preferable. First, one or two or more raw material monomers are emulsion-polymerized to form core particles, and then another one or two or more monomers are emulsion-polymerized in the presence of the core particles. To form a shell around. Next, if necessary, one or more kinds of monomers are emulsion-polymerized in the presence of particles comprising a core and a shell to form another shell. By repeating such a polymerization reaction, the target acrylic-based multilayer polymer particles (Y) can be produced as an emulsified latex. In the obtained latex, usually, a linear methacrylic resin having a methyl methacrylate unit is present in addition to the acrylic multilayer polymer particles (Y).

The content of the acrylic multi-layer polymer particles (Y) used in the present invention is preferably at least 40% by mass, more preferably at least 50% by mass, based on the total mass of the layer (B). , 62% by mass or more. Further, the content of the acrylic multilayer structure polymer particles (Y) is preferably 80% by mass or less, more preferably 70% by mass or less, based on the total mass of the layer (B). It is particularly preferred that the content is not more than mass%.
Note that the content of the acrylic multilayer polymer particles (Y) is determined by the following method using acetone.
After the acrylic resin composition constituting the layer (B) is sufficiently dried to remove water, the mass (W1) is measured. Next, this acrylic resin composition is put into a test tube, acetone is added and dissolved, and the acetone-soluble portion is removed. Thereafter, acetone is removed using a vacuum heating dryer to obtain a residue. Fine particles are separated from the residue, and the mass (W2) of the obtained residue is measured. Based on the following formula, the content of the acrylic multilayer polymer particles (Y) is determined.
[Content of Acrylic Multilayer Polymer Particles (Y)] = (W2 / W1) × 100 (%)

[Methacrylic resin (M)]
The acrylic resin composition used for the acrylic film contains the acrylic multilayer polymer particles (Y) and 80% by mass or more of methyl methacrylate units, and has a melt flow rate of 0.5 to 10 g / 10 min. It is preferable to include the methacrylic resin (M). As the methacrylic resin (M), one type may be used alone, or two or more types may be used.

(4) The methacrylic resin (M) may contain 20% by mass or less of a copolymerizable vinyl monomer unit as needed in accordance with the methyl methacrylate unit. The vinyl monomer is not particularly limited, and examples thereof include acrylate monomers such as methyl acrylate; methacrylate; aromatic vinyl compounds; These may be used alone or in combination of two or more.

The melt flow rate of the methacrylic resin (M) is preferably 1 g / 10 min or more, more preferably 1.2 g / 10 min or more. The melt flow rate of the methacrylic resin (M) is preferably 5 g / 10 minutes or less, more preferably 3 g / 10 minutes or less. When the melt flow rate of the methacrylic resin (M) exceeds the above range, the acrylic resin composition (R1) containing the methacrylic resin (M) and the acrylic multilayer polymer particles (Y) is melt-molded. In this case, the toughness tends to decrease. When the melt flow rate of the methacrylic resin (M) is less than the above range, the fluidity when the acrylic resin composition (R1) is melt-molded tends to decrease. The methacrylic resin (M) having a melt flow rate of 0.5 to 10 g / 10 min can be prepared, for example, by appropriately adjusting the amount of an acrylate or chain transfer agent used in combination with the polymerization of a monomer containing methyl methacrylate. It can be obtained by adjusting.

It is easy for the methacrylic resin (M) to increase the transparency of the layer (B) because the methacrylic resin (M) is composed of a polymer whose refractive index measured based on ASTM D542 is in the range of 1.485 to 1.495. Preferred from a viewpoint.

The blending amount of the methacrylic resin (M) in the acrylic resin composition (R1) obtained by mixing the acrylic multilayer polymer particles (Y) and the methacrylic resin (M) is not particularly limited, and the acrylic multilayer structure weight is not limited. The amount is preferably at least 1 part by mass, more preferably at least 5 parts by mass, particularly preferably at least 15 parts by mass, per 100 parts by mass of the united particles (Y). The amount of the methacrylic resin (M) to be blended is preferably 100 parts by mass or less, more preferably 70 parts by mass or less, and preferably 45 parts by mass, based on 100 parts by mass of the acrylic multilayer polymer particles (Y). Parts or less is particularly preferred. If the amount of the methacrylic resin (M) is more than 100 parts by mass, it is difficult to adjust the tensile storage modulus E ′ (120) at 120 ° C. of the resin material constituting the layer (B) to a desired range. Tend to be.

As the methacrylic resin (M), a commercially available product or a product specified in ISO8257-1 can be used.
The methacrylic resin (M) can be polymerized by a known method and used. Here, the polymerization method of the methacrylic resin (M) is not particularly limited, and examples thereof include an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, and a solution polymerization method.

[Acrylic block copolymer (Z)]
The methacrylic acid ester polymer block (z1) has a structural unit derived from a methacrylic acid ester as a main structural unit. The ratio of the structural unit derived from methacrylic acid ester in the methacrylic acid ester polymer block (z1) is preferably 80% by mass or more, more preferably 90% by mass or more, and preferably 95% by mass or more. Is more preferable, and particularly preferably 98% by mass or more.

As the methacrylate, methyl methacrylate is more preferred from the viewpoint of improving transparency and heat resistance. The methacrylic acid ester can form a methacrylic acid ester polymer block (z1) by polymerizing one kind alone or two or more kinds in combination.

(4) The weight average molecular weight Mw (z1) of the single unit of the methacrylate polymer block (z1) is preferably 5,000 or more, and more preferably 150,000 or less. Further, the weight average molecular weight Mw of a single unit of the methacrylate polymer block (z1) is more preferably 8,000 or more, and further preferably 12,000 or more. Further, the weight average molecular weight Mw is more preferably 120,000 or less, further preferably 100,000 or less.

In the block copolymer (Z), when there are a plurality of methacrylate polymer blocks (z1) in one molecule, the composition ratio and molecular weight of the constituent units constituting each methacrylate polymer block (z1) are as follows. , May be the same or different.

The proportion of the methacrylic acid ester polymer block (z1) in the block copolymer (Z) is preferably 10% by mass or more from the viewpoints of transparency, flexibility, moldability and surface smoothness, and is preferably 60% by mass. % Is more preferable. When the ratio of the methacrylic acid ester polymer block (z1) in the block copolymer (Z) is 10% by mass or more and 60% by mass or less, the layer (B) composed of the acrylic resin composition of the present invention is used. Excellent in transparency, flexibility, bending resistance, impact resistance, flexibility and the like. When the block copolymer (Z) includes a plurality of methacrylate ester polymer blocks (z1), the above ratio is calculated based on the total mass of all the methacrylate ester polymer blocks (z1).

The acrylate polymer block (z2) has a structural unit derived from an acrylate ester as a main structural unit. The proportion of the constituent unit derived from the acrylate in the acrylate polymer block (z2) is preferably 45% by mass or more, more preferably 50% by mass or more, and preferably 60% by mass or more. Is more preferably 90% by mass or more.

Examples of the acrylate include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, acrylic acid Amyl, isoamyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, pentadecyl acrylate, dodecyl acrylate, isobornyl acrylate, phenyl acrylate, benzyl acrylate, phenoxyethyl acrylate, acrylic acid 2 -Hydroxyethyl, 2-methoxyethyl acrylate, glycidyl acrylate, allyl acrylate and the like. The acrylate ester can form an acrylate polymer block (z2) by polymerizing one kind alone or two or more kinds in combination.

The acrylate polymer block (z2) is preferably composed of an acrylate alkyl ester and an acrylate aromatic ester from the viewpoint of improving the transparency of the acrylic resin composition (R2) described below. When the acrylate polymer block (z2) is composed of an alkyl acrylate and an aromatic acrylate, the acrylate polymer block (z2) is composed of 50 to 90 structural units derived from the alkyl acrylate. It is preferable that the composition contains 50% by mass and 50 to 10% by mass of structural units derived from an aromatic (meth) acrylate.

The weight average molecular weight Mw (z2) of the single unit of the acrylate polymer block (z2) is preferably at least 5,000, more preferably at least 15,000, and at least 30,000. Is particularly preferred. The weight average molecular weight Mw (z2) of a single unit of the acrylate polymer block (z2) is preferably 120,000 or less, more preferably 110,000 or less, and 100,000 or less. Is particularly preferred.

The proportion of the acrylate polymer block (z2) in the block copolymer (Z) is preferably 10% by mass or more, from the viewpoint of transparency, flexibility, moldability, and surface smoothness, and is preferably 20% by mass. %, More preferably 60% by mass or less, and even more preferably 55% by mass or less. When the proportion of the acrylate ester polymer block (z2) in the block copolymer (Z) is in the range of 10% by mass or more and 60% by mass or less, the layer (B) composed of the acrylic resin composition of the present invention is used. Excellent impact resistance, flexibility, etc. When the block copolymer (Z) includes a plurality of acrylate polymer blocks (z2) in one molecule, the above ratio is based on the total mass of all the acrylate polymer blocks (z2). calculate.

結合 The form of bonding between the methacrylate polymer block (z1) and the acrylate polymer block (z2) of the block copolymer (Z) is not particularly limited. For example, one in which one terminal of an acrylate polymer block (z2) is connected to one terminal of a methacrylate polymer block (z1) [a diblock copolymer having a (z1)-(z2) structure]; methacrylic acid One in which both ends of an ester polymer block (z1) are connected to one end of an acrylate polymer block (z2) [(z2)-(z1)-(z2) structure triblock copolymer]; One in which one end of a methacrylate polymer block (z1) is connected to each of both ends of an acrylate polymer block (z2) [triblock copolymer having a structure of (z1)-(z2)-(z1)] And a methacrylate polymer block (z1) and an acrylate polymer block (z2) are connected in series. It is below.

ブロック Further, the block copolymer (Z) may have a polymer block (z3) other than the methacrylate polymer block (z1) and the acrylate polymer block (z2).

The block copolymer (Z) may have a functional group such as a hydroxyl group, a carboxyl group, an acid anhydride, or an amino group in a molecular chain or at a molecular chain terminal, if necessary.

重量 The weight average molecular weight Mw (Z) of the block copolymer (Z) is preferably 52,000 or more, more preferably 60,000 or more. The weight average molecular weight Mw (Z) of the block copolymer (Z) is preferably at most 400,000, more preferably at most 300,000. When the weight average molecular weight of the block copolymer (Z) is small, sufficient melt tension cannot be maintained in melt extrusion molding, and it is difficult to obtain a good plate-like molded product, and the breaking strength of the obtained plate-like molded product Etc. tend to decrease in mechanical properties. On the other hand, when the weight average molecular weight of the block copolymer (Z) is large, the viscosity of the molten resin increases, and fine grain-like irregularities and unmelted material (high (Molecular weight)), and it tends to be difficult to obtain a good plate-like molded product.

Further, Mw (Z) / Mn (Z), which is a ratio between the weight average molecular weight Mw (Z) representing the molecular weight distribution of the block copolymer (Z) and the number average molecular weight Mn (Z), is 1.0 or more. It is preferably 2.0 or less, more preferably 1.6 or less. When the molecular weight distribution is within such a range, the content of the unmelted material that causes the occurrence of bumps can be extremely small in the interlayer film for laminated glass of the present invention.

The melt viscosity [η (Z)] of the block copolymer (Z) at 220 ° C. and a shear rate of 122 / sec is preferably in the range of 75 to 1500 Pa · s. The melt viscosity [η (Z)] is more preferably 150 Pa · s or more, and particularly preferably 300 Pa · s or more. Further, the melt viscosity [η (Z)] is more preferably 1,000 Pa · s or less, and particularly preferably 700 Pa · s or less. When the melt viscosity [η (Z)] is in the range of 75 to 1500 Pa · s, it has excellent mechanical properties such as breaking strength, and is caused by fine grain-like irregularities on the surface and unmelted material (high molecular weight material). It is possible to obtain a good film in which the occurrence of dust is suppressed.

The value of the ratio [η (M) / η (Z)] of the melt viscosity [η (M)] and the melt viscosity [η (Z)] of the methacrylic resin (M) at 220 ° C. and a shear rate of 122 / sec. Is preferably 1 or more, more preferably 5 or more, and still more preferably 6 or more. The value of [η (M) / η (Z)] is preferably 20 or less, more preferably 10 or less, and even more preferably 8 or less. When the value of η (M) / η (Z) is in the range of 1 to 20, good dispersibility can be ensured, and a film having excellent mechanical properties and optical properties can be obtained.

The respective melt viscosities of the methacrylic resin (M) and the block copolymer (Z) at 220 ° C. and a shear rate of 122 / sec were measured at 220 ° C. using a Capillograph (manufactured by Toyo Seiki Seisakusho, Model 1D). The molten resin can be extruded from a capillary having a diameter of 1 mmΦ and a length of 10 mm at a piston speed of 10 mm / min, and can be determined from the shear stress generated at that time.

The refractive index of the block copolymer (Z) measured based on ASTM D542 is preferably 1.485 or more, more preferably 1.487 or more. The refractive index of the block copolymer (Z) is preferably 1.495 or less, more preferably 1.493 or less. When the refractive index of the block copolymer (Z) is in the range of 1.485 to 1.495, the transparency of the layer (B) becomes high. In this specification, the term “refractive index” means a value measured at a measurement wavelength of 587.6 nm (d-line) as specified in ASTM D542.

方法 The method for producing the block copolymer (Z) is not particularly limited, and a method according to a known method can be employed. For example, a method of living-polymerizing monomers constituting each polymer block is generally used. Examples of such a living polymerization method include a method in which an organic alkali metal compound is used as a polymerization initiator, an anion polymerization is performed in the presence of a mineral acid salt such as an alkali metal or an alkaline earth metal salt, and a method in which an organic alkali metal compound is polymerized. Method of anionic polymerization in the presence of an organoaluminum compound using as an initiator, method of polymerization using an organic rare earth metal complex as a polymerization initiator, method of radical polymerization in the presence of a copper compound using an α-halogenated ester compound as an initiator And the like. Further, a method of polymerizing monomers constituting each block by using a polyvalent radical polymerization initiator or a polyvalent radical chain transfer agent to produce a mixture containing the block copolymer (Z) used in the present invention, or the like. Are also mentioned. Among these methods, in particular, the block copolymer (Z) can be obtained with high purity, the molecular weight and the composition ratio can be easily controlled, and it is economical. And a method of anionic polymerization in the presence of an organic aluminum compound is preferred.

The acrylic resin composition (R2) used for the acrylic film contains the block copolymer (Z) and 80% by mass or more of methyl methacrylate units, and has a melt flow rate of 0.5 to 10 g / 10 min. It is preferable to include the methacrylic resin (M). The content of the block copolymer (Z) in the acrylic resin composition (R2) is 1 part by mass or more based on 100 parts by mass in total of the methacrylic resin (M) and the block copolymer (Z). And more preferably at least 10 parts by mass. The content of the block copolymer (Z) is preferably 90 parts by mass or less, more preferably 45 parts by mass or less, based on 100 parts by mass of the total of the methacrylic resin (M) and the block copolymer (Z). More preferably, it is even more preferably 30 parts by mass or less. When the content of the methacrylic resin (M) in the acrylic resin composition (R2) is smaller than the content of the block copolymer (Z), the surface hardness of the sheet obtained by melt extrusion molding using a T die decreases. Tend.

Any polyvinyl acetal resin film can be used as the layer (B) as long as it satisfies the formulas (1) and (2). The polyvinyl acetal resin film used as the layer (B) can be manufactured with reference to the materials and the production method used for the layer (A) described above.
However, regarding the polyvinyl acetal resin film used as the layer (B), from the viewpoint of controlling the tensile storage modulus of the resin material constituting the layer (B) to a desired range, the polyvinyl acetal resin in the layer (B) is used. The viscosity average polymerization degree of the polyvinyl alcohol-based resin used as the raw material is preferably 1,000 or more, more preferably 1500 or more. The polyvinyl acetal resin in the layer (B) is formed by a reaction between at least one polyvinyl alcohol-based resin and at least one aliphatic unbranched aldehyde having 2 to 10 carbon atoms. However, the content of acetaldehyde in the aldehyde used for acetalization is preferably 40% by mass or more, more preferably 60% by mass or more, further preferably 80% by mass or more, and may be 100% by mass. . The aldehyde used for acetalization may be a mixture of acetaldehyde and butyraldehyde.

ポリビニル The polyvinyl acetal resin film used as the layer (B) may contain a plasticizer. As such a plasticizer, the plasticizer which may be contained in the layer (A) described above can be used. The amount of the plasticizer in the polyvinyl acetal resin film is preferably 0 to 20% by mass, more preferably 0 to 10% by mass, and particularly preferably 0 to 5% by mass, based on the total mass of the polyvinyl acetal resin film. is there.

Any PET film can be used as the layer (B) as long as it satisfies the formulas (1) and (2).

(Other additives)
The layer (B) of the present invention may contain one or more optional components as necessary, in addition to the components described above, as long as the object of the present invention is not impaired.
Optional components include antioxidants, thermal deterioration inhibitors, ultraviolet absorbers, light stabilizers, heat ray shielding agents, plasticizers, lubricants, mold release agents, polymer processing aids, adhesion regulators, antistatic agents, Examples include flame retardants, dyes and pigments, organic dyes, impact modifiers, foaming agents, fillers, and various additives such as phosphors.

The total amount of the various additives is not particularly limited, and is generally preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and preferably 20% by mass, based on the total mass of the layer (B). Or less, more preferably 10% by mass or less, particularly preferably 5% by mass or less.

As the ultraviolet absorber, antioxidant and light stabilizer, those which can be contained in the above-mentioned layer (A) can be used.

<Heat deterioration inhibitor>
The thermal degradation inhibitor is capable of preventing thermal degradation of a resin by capturing polymer radicals generated when exposed to high heat under a substantially oxygen-free state. Examples of the thermal deterioration inhibitor include 2-t-butyl-6- (3′-t-butyl-5′-methyl-hydroxybenzyl) -4-methylphenyl acrylate (Sumitomo Chemical Co., Ltd .; trade name Sumilizer GM); And 2,4-di-t-amyl-6- (3 ', 5'-di-t-amyl-2'-hydroxy-α-methylbenzyl) phenyl acrylate (Sumitomo Chemical Co., Ltd .; trade name Sumilizer GS). preferable.

<Polymer processing aid>
As the polymer processing aid, for example, polymer particles produced by an emulsion polymerization method and comprising 60% by mass or more of a methyl methacrylate unit and 40% by mass or less of a vinyl monomer unit copolymerizable therewith may be used. Used. The polymer processing aid preferably has an intrinsic viscosity of 3 to 6 dl / g.

When the layer (B) contains metal oxide fine particles having a heat ray shielding function, the content of the metal oxide fine particles is preferably 0.001 to 100 parts by mass of the thermoplastic resin in the layer (B). It is at least 0.002 parts by mass, more preferably at least 0.002 parts by mass, preferably at most 2 parts by mass, more preferably at most 1.5 parts by mass. When the content of the metal oxide fine particles is equal to or more than the lower limit, the expected heat ray shielding effect is easily obtained. When the content of the metal oxide fine particles is equal to or less than the upper limit, good transparency of the layer (B) is obtained. Is easy to be retained.
In a preferred embodiment of the present invention, the layer (B) contains metal oxide fine particles having a heat ray shielding function.

<Interlayer adhesion regulator>
In order to adjust the adhesive strength between the layer (B) and the layer (A), an interlayer adhesion modifier may be added to the layer (B) or the layer (A). Examples of the interlayer adhesion modifier that may be added to the layer (B) include carboxyl groups, carboxyl derivative groups, epoxy groups, boronic acid groups, boronic acid group derivative groups, alkoxyl groups, and alkoxyl group derivative groups. Examples include polyolefins having an adhesive functional group.

Particularly, by adding a polyolefin having an adhesive functional group to the layer (B), the adhesive strength between the layer (B) and the layer (A) can be suitably adjusted. The addition amount of the polyolefin having an adhesive functional group is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and preferably 10 parts by mass or less, based on 100 parts by mass of the thermoplastic resin of the layer (B). More preferably, the amount is not more than part by mass. If the amount of the polyolefin having an adhesive functional group exceeds 20 parts by mass, haze may be deteriorated when a laminated glass is produced. As the polyolefin having an adhesive functional group, among the above-mentioned polyolefins, a polypropylene containing a carboxyl group is easily available, easy to adjust adhesiveness, and from the viewpoint of easy adjustment of haze. It is suitable.

方法 The method for producing the layer (B) is not particularly limited. The method for manufacturing the layer (A) described above can be employed. A commercially available film can be used as the layer (B). For example, commercially available acrylic films include PARAPURE (registered trademark) JS and PARAPURE (registered trademark) HI manufactured by Kuraray Co., Ltd., and commercially available PET films include Cosmoshine (registered trademark) manufactured by Toyobo Co., Ltd. A4300).

[Another polyvinyl acetal resin layer (C)]
In a preferred embodiment of the present invention, the laminated film further has another polyvinyl acetal resin layer (C). When the laminated film has the layer (C), the layer (C) may be a single layer or a multilayer, and may be arranged at any position of the laminated film.

The layer (C) contains a polyvinyl acetal resin and a plasticizer. As the polyvinyl acetal resin or the plasticizer contained in the layer (C), the polyvinyl acetal resin or the plasticizer described for the layer (A) can be used. Those preferred embodiments, manufacturing methods, and the like described for the layer (A) can be similarly applied to the layer (C), except for the embodiments specifically mentioned below for the layer (C).

The content of the polyvinyl acetal resin in the layer (C) is not particularly limited. It is preferably 84.0% by mass or less, more preferably 60.0 to 83.9% by mass, based on the total mass of the layer (C).
In the initial state before lamination, the content of the plasticizer in the layer (C) is preferably 16.0% by mass or more, more preferably 16.1% by mass or more, based on the total mass of the layer (C). More preferably, it is more than 20.0% by mass, still more preferably 22.0% by mass or more, particularly preferably 26.0% by mass or more, preferably 36.0% by mass or less, more preferably 32.0% by mass. Or less, particularly preferably 30.0% by mass or less. When the plasticizer content is in the range between the lower limit and the upper limit, a laminated glass having excellent impact resistance is easily obtained. Further, a layer (C) having a sound insulating property can be used as the layer (C). In this case, the content of the plasticizer in the initial state is preferably 30% by mass or more, more preferably 30 to 50% by mass, and still more preferably 31 to 45% by mass, based on the total mass of the layer (C). It is particularly preferably from 32 to 42% by mass.
The layer (C) may contain, in addition to the polyvinyl acetal resin and the plasticizer, the additives described in the paragraph of [Other additives] for the layer (A) as necessary. However, the total amount of the polyvinyl acetal resin and the plasticizer in the layer (C) is preferably 90% by mass or more.

The layer (C) may have a wedge-shaped cross-sectional shape with one end face being thick and the other end face being thin. In that case, the cross-sectional shape may be a shape that is entirely wedge-shaped so that the thickness gradually decreases from one end face side to the other end face side, or a section between the one end face and the other end face. The cross-section may be wedge-shaped so that the thickness is the same up to an arbitrary position and the thickness gradually decreases from the arbitrary position to the other end surface, or as long as there is no problem in manufacturing, It may have an arbitrary cross-sectional shape regardless of the position. The layer whose cross-sectional thickness changes may be all layers or only some layers. When the layer (C) has such a cross-sectional shape, the laminated film of the present invention has a wedge-shaped thickness profile even when the thickness profile of a film or a layer other than the layer (C) is a parallel plane. And can be used in head-up displays (HUD) in automotive windshields.

The layer (C) may be a single layer or a multilayer, and the total thickness of the layer (C) is preferably 1100 to 100 μm, more preferably 1000 to 200 μm, and particularly preferably 900 to 300 μm. When the total thickness of the layer (C) is within the above range, it is easy to achieve both the expression of the function of the layer (C) (for example, impact resistance or sound insulation) and reduction in weight. The thickness of the layer (C) can be measured using a thickness gauge or a laser microscope.

Layer (C) may also be a commercially available plasticizer-containing polyvinyl acetal resin sheet.
The tensile storage modulus E ′ (40) at 40 ° C. of the resin material constituting the layer (C) is preferably less than 1000 MPa, or the tensile storage modulus E at 100 ° C. of the resin material constituting the layer (C). '(100) is preferably less than 10 MPa.

[Functional layer (D)]
In a preferred embodiment of the present invention, the laminated film further has a functional layer (D). When the laminated film has the layer (D), the layer (D) may be a single layer or a multilayer, and may be arranged at any position of the laminated film. When the laminated film has a plurality of layers (D), the type of each functional layer may be the same or different. From the viewpoint that it is possible to suppress the distortion of the layer (D) or the deterioration of the transparency of the laminated glass and to easily obtain a laminated glass having a 3D shape that is required to follow the shape, either one of the surfaces of the layer (A) or The layer (D) is preferably provided on a surface having an arithmetic average roughness (Ra) of 0.15 μm or less among the two surfaces of the layer (B).
The functional layer (D) includes a colored layer, a light absorbing layer (an electromagnetic wave absorbing layer having a specific wavelength such as an infrared absorbing layer or an ultraviolet absorbing layer), and a light reflecting layer (for example, an electromagnetic wave having a specific wavelength such as an infrared reflecting layer or an ultraviolet reflecting layer). (Reflective layer), heat ray shielding coating layer, light scattering layer, light emitting layer (fluorescent or light emitting layer), conductive layer (conductive structure), fiber layer, double image prevention layer, color correction layer, electrochromic layer, photochromic At least one layer selected from the group consisting of a layer, a thermochromic layer, a design layer, and a high elastic modulus layer. When the laminated film has the layer (D), the layer (D) may be laminated on the entire surface of the laminated film, or may be laminated on a part thereof.

The thickness of the layer (D) is preferably 2 to 300 μm, more preferably 5 to 200 μm. When the thickness of the layer (D) is within the above range, a desired function of the layer (D) (for example, conductivity, heat ray shielding property, light absorbing property, or the like) is likely to be exhibited. The thickness of the layer (D) can be measured using a thickness gauge, a laser microscope, or the like.

好ましい In a preferred embodiment of the present invention, the layer (D) is a heat ray shielding coating layer having a thickness of 0.01 to 200 μm. The thickness of the heat ray shielding coating layer as the layer (D) is preferably 100 μm or less, more preferably 60 μm or less. When the thickness of the heat ray shielding coating layer is equal to or less than the upper limit, excellent transparency of the laminated film is easily secured.

では In another preferred embodiment of the present invention, the layer (D) is a conductive structure. In the present invention, the conductive structure includes a discontinuous conductive structure, and is not a planar layer, but an individually identifiable structure, for example, a conductor track, a conductive wire, and a mesh-like structure composed of them. , A point, or a combination thereof. The discontinuous conductive structure may be provided on the surface of the layer (A) or the layer (B), or may be embedded in the surface.

The conductive structure preferably contains a metal (for example, gold, silver, copper, indium, zinc, iron, or aluminum) and / or a metal oxide as a conductive material. Instead of or in combination with the conductive material, a semiconductor material can also be suitably arranged in layer (B). Further, the conductive structure may include a carbon-based conductive material, for example, graphite, CNT (carbon nanotube), or graphene.
In a preferred embodiment of the present invention, the conductive structure contains at least one conductive material selected from the group consisting of gold, silver, copper and metal oxide.

The lamination of the layer (D) is performed by coating, laminating or printing the material constituting the layer (D) on at least one surface of either the layer (A) or the layer (B), or the layer (D) by the layer (A). Alternatively, it can be carried out by a method of coating, laminating, or printing a material constituting any of the layers (B). The method of coating, laminating or printing the material is not particularly limited.

As a method of coating the material, for example, a method of coating the layer (D) with a melt of a resin material constituting either the layer (A) or the layer (B) [for example, A method of melt-extruding a resin material, or a method of applying the resin material on the layer (D) by knife coating or the like]; a layer (A) or a layer (B) formed by vapor deposition, sputtering or electric vapor deposition. A method of applying D); when the layer (D) is made of a resin material, simultaneously extruding the resin material constituting either the layer (A) or the layer (B) and the resin material constituting the layer (D); Or a method of dipping either the layer (A) or the layer (B) in a solution of the resin material constituting the layer (D).

As a method of laminating the material, for example, a method of laminating the layer (D) and any of the layer (A) or the layer (B) and thermocompression bonding; a solvent or any of the layer (A) or the layer (B) A solution of the resin material containing the resin and the solvent contained in the layer (D) and / or the layer (A) or the layer (B), or the layer (D) and the layer (A). ) Or the layer (B), and bonding the layer (D) and the layer (A) or the layer (B); or the layer (D) and the layer (A) with an adhesive. Or a method of bonding with any of the layers (B). The adhesive used in the bonding method using the adhesive may be an adhesive generally used in the art, such as an acrylate adhesive, a urethane adhesive. , Epoxy-based adhesives and hot-melt adhesives. In an aspect in which excellent optical characteristics are required, the layer (D) is joined to either the layer (A) or the layer (B) without using an adhesive from the viewpoint that haze derived from the adhesive does not occur. Is preferred.

Examples of a method for printing the material include screen printing, flexographic printing, and gravure printing. In the printing method, an ink that is dried or cured by heat or light is used before laminating a polyvinyl acetal resin film having a layer in a subsequent process. When a printing method ("printed electronics") is used, the ink or printing ink used contains conductive particles. The conductive particles are metal particles, for example, gold, silver, copper, zinc, iron or aluminum particles, metal-coated materials, for example, silver-plated glass fiber or glass globule particles, or conductive carbon black, carbon It can be a particle of nanotubes, graphite or graphene. Further, semiconductor particles, for example, particles of a conductive metal oxide such as indium-doped tin oxide, indium-doped zinc oxide or antimony-doped tin oxide. Among them, as the conductive particles, particles of gold, silver, copper, or a conductive metal oxide are preferable.
In a preferred embodiment of the present invention, the conductive structure is formed by a printing method, an etching method, or an evaporation method.

In a mode in which the layer (D) is a conductive structure and the conductive structure is based on a metal foil, the step of bonding the metal foil to the layer (A) or the layer (B) includes, for example, the following method (I) to (III).
(I) a method in which the layer (A) or the layer (B) and the metal foil are overlapped and thermocompression-bonded,
(II) A method of coating and joining a melt of the resin material constituting the layer (A) or the layer (B) on the metal foil, for example, a method of melt-extruding the resin material on the metal foil, or a method of melting the metal foil A method in which the resin material is applied thereon by knife coating or the like, or (III) a solvent or a solution or a dispersion of the resin material containing the resin and the solvent contained in the layer (A) or the layer (B), using a metal foil and It is applied to one or both of the layer (A) and the layer (B), or is injected between the metal foil and the layer (A) or the layer (B), and the metal foil and the layer (A) or the layer (B) are injected. And how to join.

The bonding temperature at the time of thermocompression bonding in the above method (I) depends on the kind of the resin contained in the layer (A) or the layer (B), but is usually 90 to 170 ° C, preferably 100 to 160 ° C, more preferably. Is 110 to 155 ° C, more preferably 110 to 150 ° C. When the joining temperature is within the above range, good joining strength is easily obtained.
The resin temperature during extrusion in the above method (II) is preferably from 150 to 250 ° C, more preferably from 170 to 230 ° C, from the viewpoint of reducing the content of volatile substances in the layer (A) or the layer (B). . In order to remove volatile substances efficiently, it is preferable to remove the volatile substances from the vent port of the extruder under reduced pressure.
As the solvent in the above method (III), it is preferable to use a plasticizer usually used for a polyvinyl acetal resin. As such a plasticizer, those described in the paragraph <Plasticizer> above are used.

工程 The step of forming a desired shape of the conductive structure from the obtained metal foil-attached layer (A) or layer (B) is performed by using a known photolithography technique. In this step, for example, as described in Examples below, first, a dry film resist is laminated on the metal foil of the layer (A) or the layer (B) with a metal foil, and then the etching resistance is determined using a photolithography technique. After the pattern is formed, the layer (A) or the layer (B) provided with the etching resistance pattern is immersed in a copper etching solution to form the shape of the conductive structure, and the remaining photoresist is formed by a known method. This is done by removing the layer.

In general, conductive structures are used to electromagnetically shield frequency electromagnetic fields or to heat part or all of laminated glass, to create electrical circuits, such as wiring or transmitting and / or receiving antennas and other functions. What can be used. Due to the fact that the laminated film has a conductive structure, for example, a heating element can be introduced into the laminated glass, and the antenna can be used, for example, for receiving radio waves in the automotive field or in inter-vehicle communication.

The conductive structure may be finished as a contact sensor, which allows the production of laminated glass that interacts with other electronic components. Thus, for example, information input on a laminated glass (for example, a windshield or side glass of a passenger car, or a glass of a door) can be used for access control.

If the conductive structure is an electronic component, that is, a multilayer structure of conductive and dielectric structures, an additional electronic circuit or component may be provided. All such electronic circuits or components include, in particular, transistors, resistors, chips, sensors, displays, light emitting diodes (eg OLEDs) and / or smart labels.

The conductive structure may be very small and may not be sufficiently recognized by the naked eye. The width of the conductive structure is preferably 1 μm or more, preferably 30 μm or less, more preferably 20 μm or less, and particularly preferably 15 μm or less. In particular, in the case of a flat heating zone (Heizfelder), the width of the filament is less than 25 μm. The heating area may be introduced only locally, for example only before the optical sensor system above the windshield.

[Peelable protective film]
The laminated film of the present invention may have a peelable protective film on the outermost layer. Therefore, another object of the present invention is a laminated film with a protective film having a peelable protective film on the outermost layer of the laminated film. As such a protective film, those commonly used in the art can be used.

[Laminated film]
The laminated structure in the laminated film of the present invention is determined depending on the purpose. For example, it may have the following laminated structure, but is not limited thereto.
Layer (A) / layer (B) / layer (A), layer (A) / layer (B) / layer (C), layer (A) / layer (B) / layer (D),
Layer (A) / layer (B) / layer (A) / layer (B), layer (A) / layer (B) / layer (C) / layer (A), layer (A) / layer (B) / Layer (A) / layer (C), layer (A) / layer (B) / layer (D) / layer (C),
Layer (A) / layer (B) / layer (A) / layer (B) / layer (A), layer (A) / layer (C) / layer (B) / layer (C) / layer (A) , Layer (A) / layer (C) / layer (B) / layer (A) / layer (C), layer (A) / layer (B) / layer (C) / layer (A) / layer (C) , Layer (C) / layer (A) / layer (B) / layer (A) / layer (C), layer (A) / layer (B) / layer (D) / layer (C) / layer (A) ,
Layer (C) / layer (A) / layer (B) / layer (C) / layer (A) / layer (C) and layer (C) / layer (A) / layer (C) / layer (B ) / Layer (C) / layer (A) / layer (C).
Among them, particularly, layer (A) / layer (B) / layer (C), layer (A) / layer (B) / layer (D) and layer (A) / layer (B) / layer (D) / The configuration of the layer (C) is preferred, and the configuration of the layer (A) / layer (B) / layer (D) / layer (C) is particularly preferred.

Among the above, a laminated structure in which the layer (B) is laminated between at least two layers (A) is preferable, and from the viewpoint of easily obtaining good adhesion to glass, the layer (A) is the outermost layer. It is preferable that at least one layer is formed.
Further, from the viewpoint of penetration resistance when the laminated glass is used, the laminated film preferably has at least one layer (C) in addition to the layer (A) and the layer (B). In this case, the layer (C) is preferably in contact with the layer (B) side of the layer (A) / layer (B), and the layer (D) exists on the layer (A) or the layer (B). Is preferably in contact with the layer (D).

When the layer (C) is present in the laminated film of the present invention, the content of the vinyl alcohol unit in the polyvinyl acetal resin in the layer (A) and the content of the vinyl alcohol unit in the polyvinyl butyral resin in the layer (C) are determined. The difference is preferably at most 6 mol%, more preferably at most 4 mol%, particularly preferably at most 3 mol%. When the polyvinyl butyral resin in the layer (A) and / or the layer (C) is composed of a mixture of a plurality of resins, the vinyl alcohol unit content of at least one polyvinyl acetal resin contained in the layer (A) and the layer ( It is preferable that the difference from the vinyl alcohol unit content of at least one polyvinyl acetal resin contained in C) is equal to or less than the upper limit. When the difference is equal to or less than the upper limit, the difference in the refractive index between the layer (A) and the layer (C) in an equilibrium state after the plasticizer has migrated in the laminated film is small. It is preferable to use the layer (A) and the layer (A) because the boundary between them is difficult to see.
On the other hand, by making the vinyl alcohol unit content of the polyvinyl acetal resin in the layer (A) lower than the vinyl alcohol unit content of the polyvinyl butyral resin in the layer (C), It is also one of the preferable embodiments that the average amount of the plasticizer in the layer (A) in the equilibrium state is set to 30% by mass or more. In that case, the vinyl alcohol unit content of the polyvinyl acetal resin in the layer (A) is preferably at least 6 mol% lower than the vinyl alcohol unit content of the polyvinyl butyral resin in the layer (C), and more preferably 10% or less. Mol% or less. When the difference in the vinyl alcohol unit content is equal to or larger than the lower limit, the amount of the plasticizer in the layer (A) in the equilibrium state can be sufficiently increased, and a laminated glass having a sound insulation function can be easily obtained. preferable.

When the layer (A) is in contact with the layer (D), the ten-point average roughness Rz value of the bonding surface of the layer (A) with the layer (D) is preferably 20 μm or less, more preferably 5 μm or less. It is particularly preferably 3 μm or less, and the average interval Sm value of the unevenness is preferably 500 μm or more, more preferably 1000 μm or more, particularly preferably 1300 μm or more. When the Rz value is equal to or less than the upper limit value or the Sm value is equal to or greater than the lower limit value, uniform printing, coating or lamination is easily achieved, and uneven bonding between the layer (A) and the ink or metal foil or the like is caused. Easy to be suppressed.

When the layer (A) has a structure in contact with glass, the ten-point average roughness Rz value of the bonding surface of the layer (A) with glass is preferably 20 μm or less, more preferably 10 μm or less, and preferably 1 μm. The above is more preferably 2 μm or more, and the average interval Sm value of the unevenness is preferably 1500 μm or less, more preferably 1000 μm or less, particularly preferably 700 μm or less. When the Rz value is equal to or less than the upper limit value or the Sm value is equal to or less than the upper limit value, the layer (D) is excellent in degassing property, can suppress the distortion and crack of the layer (D), and hardly generate wrinkles.

The Rz value and the Sm value are measured using a surface roughness meter or a laser microscope in accordance with JIS B0601-1994.
As a method for adjusting the Rz value to the upper limit or less and the Sm value to the lower limit or more, a melt extrusion method (for example, a method using a T-die or a method of inflation molding), a solvent casting method, or the like can be adopted. . Preferably, the Rz value and the Sm value can be adjusted by forming a film of the melt extruded from the T-die using a smooth cooling roll. Further, in order to form a smoother surface, it is preferable to use a combination of an elastic roll and a mirror-finished metal roll, and it is more preferable to use a combination of a metal elastic roll and a mirror-finished metal roll.

Regarding the laminated film of the present invention, the difference in refractive index between the refractive index of the layer (A) and the refractive index of the layer (B) measured based on ASTM D542 is preferably 0.10 or less, more preferably 0.08 or less. It is. When the refractive index difference is equal to or less than the upper limit, excellent transparency of the obtained laminated glass is easily obtained. The refractive index difference can be adjusted to the upper limit or less by, for example, configuring the layer (A) with a polyvinyl acetal resin material and configuring the layer (B) with the resin material described above.

Further, with respect to the laminated film of the present invention, the haze value based on JIS K7136 of the laminated glass sandwiching the laminated film between two glasses is preferably 1.5% or less, more preferably 1.0% or less, and particularly preferably 0% or less. 0.8% or less. When the haze value is equal to or less than the upper limit, the obtained laminated glass has excellent transparency. The haze value can be adjusted to the upper limit or less, for example, by configuring the layer (A) with a polyvinyl acetal resin material and configuring the layer (B) with the resin material described above.

The laminated film of the present invention may have an adhesive layer between the layer (A) and the layer (B), but from the viewpoint of transparency of the laminated film, it may not have an adhesive layer. preferable.

[Production method of laminated film]
The laminated film of the present invention has a layer (A) and a layer (B), and optionally a layer (C) and optionally a layer (D). The manufacturing method is not particularly limited. The laminated film can be manufactured by the same method as the method of coating, laminating or printing as described in the paragraph of [Functional Layer (D)].
When the laminated film has a peelable protective film, the protective film may be laminated on the obtained laminated film by a method common in the art.

[Laminated glass]
The present invention is also directed to a laminated glass in which the laminated film of the present invention or the laminated film obtained by peeling the protective film from the laminated film with a protective film of the present invention is sandwiched between two glasses.

ガラス The glass in the present invention is preferably an organic glass or an inorganic glass from the viewpoint of transparency, weather resistance and mechanical strength. Specifically, preferably, an inorganic glass (also simply referred to as “glass” in the present specification), or a methacrylic resin sheet, a polycarbonate resin sheet, a polystyrene-based resin sheet, a polyester-based resin sheet, or a polycycloolefin Organic glass such as a system resin sheet, more preferably an inorganic glass, a methacrylic resin sheet or a polycarbonate resin sheet, and particularly preferably an inorganic glass. Examples of the inorganic glass include, but are not particularly limited to, float glass, tempered glass, semi-tempered glass, chemically strengthened glass, green glass, and quartz glass.

The laminated glass of the present invention can be manufactured by a conventionally known method. For example, on a glass, a laminated film in which the protective film is peeled off from the laminated film of the present invention or the laminated film with the protective film of the present invention is arranged, and another glass is further laminated by pre-compression bonding. Alternatively, a laminated glass can be produced by locally fusing each other and then treating in an autoclave.
Further, the production of the laminated film can be performed simultaneously with the production of the laminated glass. That is, for example, a layered film (for example, a layer A / A) in which a layer (A) and a layer (B) and optionally a layer (C) and an optional layer (D) are laminated on glass, or a part of the layers is laminated in advance. Layer B / Layer D) and one or more layers (C) are superposed in any order, and another glass is superimposed and fused to the whole surface or locally by pre-compression bonding Then, by treating in an autoclave, a laminated glass can be produced.

As a preliminary pressure bonding step, from the viewpoint of removing excess air or performing light joining of adjacent layers, a method of degassing under reduced pressure by a method such as a vacuum bag, a vacuum ring or a vacuum laminator, a nip roll And a method of compression molding at a high temperature.

The vacuum bag method or the vacuum ring method is performed at about 2 × 10 ⁴ Pa and 100 to 145 ° C., for example, as described in EP 1235683 B1.
The vacuum laminator comprises a heatable and vacuumable chamber in which laminated glass is formed within a time period of about 20-60 minutes. Usually, it is carried out at a reduced pressure of 1 Pa to 3 × 10 ⁴ Pa and a temperature of 100 to 200 ° C., particularly 130 to 160 ° C. When a vacuum laminator is used, the subsequent autoclave may not be performed depending on the temperature and the pressure.

When the treatment is performed in an autoclave, the treatment is performed, for example, at a pressure of about 1 × 10 ⁶ to 1.5 × 10 ⁶ Pa and a temperature of about 100 to 145 ° C. for about 20 minutes to 2 hours.

The laminated glass of the present invention is used, for example, as a laminated glass in a building or a vehicle. Examples of the vehicle glass include a windshield, a rear glass, a roof glass, a side glass, and the like for vehicles such as trains, trains, automobiles, ships, and aircraft.

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

[Evaluation items and evaluation methods]
<Measurement of heat creep resistance>
A layered film of layer (A) / layer (B) and a plasticized polyvinyl butyral resin film as layer (C) prepared in Examples and Comparative Examples described later were cut into dimensions of 100 mm in width and 270 mm in length. As shown in FIG. 1, the cut sample was placed between the layers A and B so that the cut sample was placed between glasses A and B having a width of 100 mm, a length of 300 mm, and a thickness of 3 mm shifted by 30 mm in the length direction. After laminating the laminated film and the plasticized polyvinyl butyral resin film as the layer (C) and arranging them in the order of “Configuration 1” below, joining them at 140 ° C. using a vacuum laminator, and then 140 ° C. using an autoclave, By treating at 1.2 MPa for 30 minutes, a laminated glass was produced.
[Configuration 1] Glass A / Laminated film (Layer A / Layer B) / Plasticized polyvinyl butyral resin film (Layer C) / Glass B
Subsequently, as shown in FIG. 2, a 1 kg iron plate is adhered to the surface of the glass B on the side opposite to the bonding surface with the plasticized polyvinyl butyral resin film with an adhesive, and as shown in FIG. The glass A is fixed so that the sample with the iron plate is at an angle of 80 to 90 ° with respect to the horizontal plane, and the portion where the iron plate of glass B is attached is the upper or upper surface of the sample, with the part protruding 30 mm upward. After leaving the glass B for one week in a thermostat at 100 ° C., the shifted distance (mm) of the glass B was measured, and this value was defined as the heat creep resistance value. Even when the angle of the sample with the iron plate with respect to the horizontal plane is any angle of 80 to 90 °, the same heat resistance creep resistance value can be obtained. Usually, the above-mentioned angle is set to 85 °, and the heat creep resistance value is measured.
The evaluation criteria for each evaluation result were as follows.
A: 15mm or less B: Longer than 15mm

<Measurement of haze value>
For the resin films used as the layers (A), (B) and (C) and the laminated glass manufactured using the layers (A) to (C) in Examples and Comparative Examples described later, a haze meter (Suga The haze value was measured according to JIS K7136 using a test machine (manufactured by Testing Machine Co., Ltd.).

<Measurement of refractive index>
The refractive index of each resin film used as the layer (A) and the layer (B) in Examples and Comparative Examples described later was measured using Calnew Optical Co., Ltd. “KPR-20” in accordance with ASTM D542.

<Measurement of arithmetic average roughness (Ra)>
The arithmetic average roughness (Ra) of each resin film used as the layer (B) in Examples and Comparative Examples described below was measured using a laser microscope according to JIS B0601: 2001. The arithmetic average roughness (Ra) can be obtained as an average value of the individual arithmetic average roughness (Ra) measured at any five places on the film surface, and this value is expressed in μm. In each resin film, the surface that comes into contact with the layer (C) or the layer (D) was measured, and the value was adopted as the arithmetic average roughness (Ra).

<Measurement of tensile storage modulus>
For the resin films used as the layer (B) in the examples and comparative examples, the tensile storage elastic moduli E ′ (40), E ′ (100) and E ′ (120) were measured by the following method.
The resin film used as the layer (B) was cut into dimensions of 3 mm in width and 3 cm in length to prepare a sample for dynamic viscoelasticity measurement. Using a dynamic viscoelastic apparatus (Rheogel-E4000 manufactured by UBM Co., Ltd.), a distance between chucks of 20 mm, a frequency of 0.3 Hz, distortion control of automatic adjustment (10 μm, 0.05%), automatic static load (minimum) The analysis was performed under static load control with a static load of 25 g and an automatic control value of 200%), at a temperature rising rate of 3 ° C./min from −100 ° C. to 140 ° C., and in a tensile mode.

<Evaluation method for wrinkles and cuts of interlayer film of 3D laminated glass>
In Examples and Comparative Examples, as a method for evaluating wrinkles / cuts of an intermediate film of a 3D laminated glass produced by a method described later, a grid-like pattern written on a layer (B) using a conductive ink at 2.5 mm intervals was used. This line was regarded as a decorative layer, and the determination was performed by a visual discrimination method. The evaluation criteria for each evaluation result were as follows.
A: No wrinkles or cuts in the interlayer film are seen.
B: Wrinkles and cuts of the intermediate film are slightly observed.
C: Interlayer wrinkles and cuts are observed.

<Method for evaluating distortion of interlayer film of 3D laminated glass>
In Examples and Comparative Examples, as a method for evaluating the distortion of the intermediate film of the 3D laminated glass produced by the method described below, a grid-like line written on the layer (B) at 2.5 mm intervals using conductive ink was used. Was regarded as a conductive structure or a decorative layer, and the degree of bending of the line was visually confirmed. The evaluation criteria for each evaluation result were as follows.
A: No lattice line distortion is observed.
B: Large distortion is seen in the grid lines.

Example 1
Resin A-1 as polyvinyl butyral resin 1 (hereinafter, referred to as “resin 1”) and resin A-2 as polyvinyl butyral resin 2 (hereinafter, referred to as “resin 2”) in a mass ratio of 75:25. They were mixed, melt-kneaded, extruded into strands, and pelletized. The obtained pellets were melt-extruded using a single screw extruder and a T-die under the following conditions, and a 50 μm-thick polyvinyl acetal resin film a having a smooth surface was obtained using a metal elastic roll, and this was used as a layer (A). Using.
Melt extrusion conditions Set temperature of extruder (melting temperature of resin material): 200 ° C,
T die width: 500mm,
T die lip opening: 0.5mm,
Discharge rate of molten resin from T-die: 15 kg / h

As the layer (B), PARAPURE (registered trademark) JS (acrylic film) manufactured by Kuraray Co., Ltd., having a thickness of 50 μm and an arithmetic average roughness (Ra) of 0.15 μm or less on both surfaces, was used. Hereinafter, this film is referred to as “PMMA-1”.
The layer (A) and the layer (B) are heated at 140 ° C. for 10 minutes using a hot press machine, and then pressurized at 1.2 MPa for 15 minutes to obtain a layer (A) / layer (B) laminated film. Was.

72% by mass of a polyvinyl butyral resin having a degree of acetalization of 70% by mol, a vinyl acetate unit content of 0.9% by mol and a viscosity average degree of polymerization of polyvinyl alcohol of about 1700 as a raw material, and 28% by mass of 3GO (plasticizer). The mixture was melt-kneaded with a screw extruder, extruded into strands, and pelletized. The obtained pellets are introduced into a uniaxial vent extruder having a screw diameter of 65 mm and a screw diameter of 50 mm, extruded from a T-die into a film, and formed into a plasticized polyvinyl butyral resin film having a thickness of 760 μm (hereinafter referred to as “PVB-1”). ), Which was used as layer (C).

<Preparation of laminated glass for optical performance evaluation (haze value measurement)>
First, the laminated film of layer (A) / layer (B) and PVB-1 as layer (C) are cut into a size of 50 mm × 50 mm, and laminated film (layer A / layer B) and layer (C) in this order. After stacking and heating at 140 ° C. for 10 minutes using a hot press machine, pressure was applied at 1.2 MPa for 15 minutes to obtain a laminated film (layer A / layer B / layer C). Next, a laminated film (layer A / layer B / layer C) is placed between two pieces of glass having a thickness of 2 mm and dimensions of 50 mm × 50 mm, put into a vacuum bag, and evacuated at 100 ° C. for 30 minutes. It was left still. The contents were taken out of the vacuum bag, and left still at 140 ° C. for 60 minutes in an autoclave to obtain a target laminated glass.

<Method for producing laminated glass for 3D shape evaluation>
The layered film of layer (A) / layer (B) and PVB-1 as layer (C) are cut out into circles each having a size of 150 mm in diameter, and one grid is formed on the surface of layer (B) of the layered film. Lattice-shaped lines were drawn with conductive ink so that the size was 5 mm × 5 mm. Next, the laminated film (layer A / layer B) and the layer (C) were laminated in this order, heated at 140 ° C. for 10 minutes using a hot press machine, and then pressed at 1.2 MPa for 15 minutes to form a laminated film (layer A / layer A / B). Layer B / layer C) was obtained. Next, a laminated film [Layer A (33) / Layer B] is placed between two disc-shaped watch glasses (3D-shaped glasses 31 and 32) having a diameter of 150 mm and a height of 15 mm so that the lamination order shown in FIG. (34) / layer C (35)] was placed and placed in a vacuum bag, and allowed to stand at 100 ° C. for 30 minutes while evacuating. The contents were taken out of the vacuum bag, and further left still at 140 ° C. for 60 minutes in an autoclave to obtain a target laminated glass 40.

各種 Various evaluations were performed on the layer (A), the layer (B), the layer (C) or the laminated glass manufactured in Example 1. Table 3 shows the evaluation results.

Example 2
As the layer (B), Kuraray Co., Ltd. having a thickness of 50 μm is used in place of PARAPURE (registered trademark) JS manufactured by Kuraray Co., Ltd., which has a thickness of 50 μm and an arithmetic average roughness (Ra) of 0.15 μm or less on both surfaces. A laminated film and a laminated glass were prepared and various evaluations were performed in the same manner as in Example 1 except that PARAPURE (registered trademark) HI (acrylic film; hereinafter, referred to as “PMMA-2”) was used. . Table 3 shows the evaluation results.

Example 3
The resin A-1 as the resin 1 and the resin A-2 as the resin 2 were mixed at a mass ratio of 25:75, and 82% by mass of the obtained mixture and 3GO (18% by mass) were melted by a twin-screw extruder. The mixture was kneaded, extruded into a strand, and pelletized. The obtained pellet was melt-extruded using a single screw extruder and a T-die, and a 50 μm-thick polyvinyl acetal resin film b having a smooth surface was obtained using a metal elastic roll. A laminated film and a laminated glass were prepared and various evaluations were performed in the same manner as in Example 2 except that the resin film b was used instead of the resin film a as the layer (A). Table 3 shows the evaluation results.

Example 4
Resin A-2 (72% by mass) and 3GO (28% by mass) as resin 1 were melt-kneaded with a twin-screw extruder, extruded into strands, and pelletized. The obtained pellets were melt-extruded using a single screw extruder and a T-die, and a 100 μm-thick polyvinyl acetal resin film c having a smooth surface was obtained using a metal elastic roll. A laminated film and laminated glass were prepared and various evaluations were performed in the same manner as in Example 2 except that the resin film c was used instead of the resin film a as the layer (A). Table 3 shows the evaluation results.

Example 5
A polyvinyl acetal resin having a degree of acetalization of 70 mol%, a vinyl acetate unit content of 0.9 mol%, and a viscosity average degree of polymerization of polyvinyl alcohol of about 2400, which was acetalized with acetaldehyde, and having a screw diameter of 65 mm and a screw diameter of 50 mm was used. A thermoplastic resin film “PVX-1” having a thickness of 50 μm and an arithmetic average roughness (Ra) of 0.15 μm or less on both sides is put into a single-screw vent extruder and extruded from a T-die into a film. Obtained. A laminated film and a laminated glass were prepared and various evaluations were performed in the same manner as in Example 1 except that PVX-1 was used instead of PMMA-1 as the layer (B). Table 3 shows the evaluation results.

Example 6
Acetalized with butyraldehyde and acetaldehyde (butyraldehyde: acetaldehyde = 1: 1), acetalization degree 70 mol%, vinyl acetate unit content 0.9 mol%, and viscosity average degree of polymerization of polyvinyl alcohol used as a raw material about 1700 Is charged into a uniaxial vent extruder having a screw diameter of 65 mm and a screw diameter of 50 mm, and extruded from a T-die into a film. The thickness is 50 μm, and the arithmetic average roughness (Ra) of both sides is 0.15 μm. The following thermoplastic resin film "PVX-2" was obtained. A laminated film and a laminated glass were prepared and various evaluations were performed in the same manner as in Example 1 except that PVX-2 was used instead of PMMA-1 as the layer (B). Table 3 shows the evaluation results.

Example 7
Example except that PET (Cosmoshine (registered trademark) A4300, thickness 50 μm, arithmetic average roughness of both sides 0.15 μm or less) manufactured by Toyobo Co., Ltd. was used as the layer (B) instead of PMMA-1. In the same manner as in Example 1, a laminated film and a laminated glass were produced, and various evaluations were performed. Table 3 shows the evaluation results.

Example 8
Example except that PET (Cosmoshine® A4300, thickness 125 μm, arithmetic mean roughness of both sides 0.15 μm or less) manufactured by Toyobo Co., Ltd. was used instead of PMMA-1 as the layer (B). In the same manner as in Example 1, a laminated film and a laminated glass were produced, and various evaluations were performed. Table 3 shows the evaluation results.

Example 9
99 mass% of the raw material resin of the resin film a and 0.2 mass% of ITO (tin-doped indium oxide, ITO-R (registered trademark) manufactured by CIK Nanotech Co., Ltd.) are melt-kneaded with a twin-screw extruder and extruded into strands. And pelletized. The obtained pellet was melt-extruded using a single screw extruder and a T-die, and a 50 μm-thick polyvinyl acetal resin film e having a smooth surface was obtained using a metal elastic roll. A laminated film and a laminated glass were produced and various evaluations were performed in the same manner as in Example 1 except that the resin film e was used instead of the resin film a as the layer (A). Table 3 shows the evaluation results.

Example 10
99.7% by mass of a raw resin of PARAPURE (registered trademark) JS manufactured by Kuraray Co., Ltd. and ITO (0.3% by mass) were melt-kneaded with a twin-screw extruder, extruded into strands, and pelletized. The obtained pellets are melt-extruded using a single screw extruder and a T-die, and a thermoplastic resin film having a smooth surface (having an arithmetic average roughness of 0.15 μm or less) and a thickness of 100 μm using a metal elastic roll. PMMA-3 "was obtained. A laminated film and a laminated glass were produced and various evaluations were performed in the same manner as in Example 1 except that PMMA-3 was used instead of PMMA-1 as the layer (B). Table 3 shows the evaluation results.

Example 11
Polyvinyl butyral resin having an acetalization degree of 70 mol%, a vinyl acetate unit content of 0.9 mol%, and a viscosity average degree of polymerization of polyvinyl alcohol of about 1700 was 71.9 mass%, 3GO (28 mass%) and ITO (0 mass%). .1% by mass) was melt-kneaded with a twin-screw extruder, extruded into strands, and pelletized. The obtained pellets are introduced into a uniaxial vent extruder having a screw diameter of 65 mm and a screw diameter of 50 mm, extruded into a film from a T-die, and formed into a 760 μm-thick ITO-containing plasticized polyvinyl butyral resin film (hereinafter, “ITO-containing PVB”). ). A laminated film and a laminated glass were produced and various evaluations were performed in the same manner as in Example 1 except that ITO-containing PVB was used instead of PVB-1 as the layer (C). Table 3 shows the evaluation results.

Example 12
The layer (A) / layer (B) laminated film obtained in Example 1 was coated with a 7 μm-thick copper foil having one surface blackened so that the blackened surface was in contact with the layer (B). Stacked in orientation. Here, the visible light reflectance of the blackened surface measured according to JIS R 3106 was 5.2%. Next, the upper and lower sides of a laminate in which a layered film of layer (A) / layer (B) and a copper foil as layer (D) are sandwiched between a 50 μm-thick PET film, and a thermocompression roll set at 120 ° C. After passing through (pressure: 0.2 MPa, speed: 0.5 m / min), the PET film was peeled off to obtain a laminated film (layer A / layer B / copper foil).
Next, after laminating a dry film resist on the copper foil of the laminated film (layer A / layer B / copper foil), an etching resistance pattern was formed using a photolithography technique. Next, the laminated film on which the etching resistance pattern was formed was immersed in a copper etching solution to form a conductive layer (conductive structure), and the remaining photoresist layer was removed by a conventional method. Thus, a laminated film (layer A / layer B / layer D) having a conductive layer as layer (D) was obtained. This laminated film has no adhesive layer between the layer (B) and the conductive layer that is the layer (D). The conductive layer has a copper mesh structure in which copper wires having a line width of 10 μm are arranged in a grid at intervals of 500 μm inside a square having a length of 5 cm and a width of 5 cm, and an upper side and a lower side thereof have a width of 5 mm corresponding to a bus bar. And a structure connected to the
A 3D shape evaluation was performed on a laminated film (layer A / layer B / layer D) having a conductive layer as layer (D). No wrinkles, cuts and distortions were observed. At this time, no disconnection or deformation occurred in the conductive layer (D).

Example 13
In order to prepare a laminated film (layer A / layer B / layer D / layer C) in place of the laminated film (layer A / layer B / layer C), the laminated film of layer (A) / layer (B) and the layer ( Laminating was carried out in the same manner as in Example 1 except that a heat ray shielding coating layer (Crystallin 70 manufactured by 3M Co., Ltd., thickness: 50 μm) as a layer (D) was further laminated between PVB-1 as C). A film and a laminated glass were produced. When the 3D shape was evaluated, no wrinkles, cuts or distortions were observed. The heat creep resistance was rated A, and the haze value of the laminated glass was 0.9.

Example 14
As a raw material for the layer (B), a raw resin for the thermoplastic resin film “PVX-2” of Example 6 was dissolved in ethanol to prepare a 7% by mass ethanol solution. The prepared ethanol solution was coated on a resin film a having a thickness of 50 μm obtained in the same manner as in Example 1 using an applicator, and dried at normal temperature and normal pressure. The thickness was 10 μm, and the arithmetic mean A thermoplastic resin film “PVX-3” having a thickness (Ra) of 0.15 μm or less was formed on the layer (A) to obtain a layer (A) / layer (B) laminated film. A laminated glass was produced in the same manner as in Example 1 except that PVX-3 was used instead of PMMA-1 as the layer (B), and a layer (A) / layer (B) laminated film was obtained by coating. Were prepared and various evaluations were made. Table 3 shows the evaluation results.

Comparative Example 1
Resin A-1 (72% by mass) and 3GO (28% by mass) as resin 1 were melt-kneaded with a twin-screw extruder, extruded into strands, and pelletized. The obtained pellet was melt-extruded using a single screw extruder and a T-die, and a 100 μm-thick polyvinyl acetal resin film d having a smooth surface was obtained using a metal elastic roll. A laminated film and a laminated glass were prepared and various evaluations were performed in the same manner as in Example 2, except that the resin film d was used instead of the resin film a as the layer (A). Table 3 shows the evaluation results.

Comparative Example 2
A resin film c ′ was prepared in the same manner as the resin film c except that the thickness was changed to 500 μm, and was the same as in Example 7 except that the resin film c ′ was used instead of the resin film a as the layer (A). Similarly, a laminated film and a laminated glass were prepared and various evaluations were performed. Table 3 shows the evaluation results.

Comparative Example 3
As layer (B) [having E '(40) = 1900 MPa and E' (100) = 700 MPa] instead of PMMA-1 [having E '(40) = 600 MPa and E' (100) = 0.5 MPa A laminated film and a laminated glass were produced in the same manner as in Example 1 except that the resin film a having a thickness of 50 μm was used, and various evaluations were made. Table 3 shows the evaluation results.

Table 1 shows the physical property values of Resin A-1 and Resin A-2 used in Examples and Comparative Examples.

Table 2 shows the compositions and glass transition temperatures of the resin materials constituting the polyvinyl acetal resin films a to e used in the examples and comparative examples.

The tensile storage elastic modulus E ′ (40) at 40 ° C. of the resin material constituting the polyvinyl acetal resin films a to e was less than 1000 MPa, and the tensile storage elastic modulus E ′ (100) at 100 ° C. was less than 10 MPa.

In Examples 1 to 14 of the present invention, it is shown that the laminated film of the present invention has both excellent heat creep resistance and good followability to 3D-shaped glass, and also provides a laminated glass having high transparency. Was. Being superior in heat creep resistance means that the distortion of the functional layer can be favorably suppressed.
On the other hand, in Comparative Example 1, as a resin component contained in the layer (A), toluene / ethanol having a concentration of 10% by mass, which was measured at 20 ° C. and 30 rpm using a Brookfield type (B type) viscometer, was 1/1/1. Due to the use of a polyvinyl acetal resin having a viscosity of 1 (mass ratio) of less than 200 mPa · s, only insufficient heat creep resistance was obtained.
Further, in Comparative Example 2, the use of the layer (A) having a thickness exceeding 350 μm deteriorated the ability to follow the 3D shape glass, and wrinkles or cuts were observed in the laminated glass.
In Comparative Example 3, the use of the layer (B) that does not satisfy the formulas (1) and (2) deteriorated the ability to follow the 3D-shaped glass, and lattice distortion was observed. This indicates that when the functional layer (D) is laminated, the distortion is not sufficiently suppressed.

The laminated film of the present invention can suppress the distortion of the functional layer or the deterioration of the transparency of the laminated glass when used as the interlayer of the laminated glass, and is excellent in conformability to the 3D shape. It can be suitably used as a laminated glass for protecting the surface of a display or an interlayer film of a laminated glass for automobiles.

10 Laminated glass for heat resistance creep resistance measurement 11 Glass A
12 Glass B
13 Laminated film of laminated film (layer A / layer B) and plasticized polyvinyl butyral resin film (layer C) 13A Laminated film (layer A / layer B)
13B Plasticized polyvinyl butyral resin film (layer C)
Reference Signs List 20 laminated glass for heat resistance creep resistance measurement bonded with iron plate 21 iron plate 31 3D-shaped glass 32 3D-shaped glass 33 layer (A)
34 layers (B)
35 layers (C)
40 Laminated glass for 3D shape evaluation

Claims

A laminated film having at least a polyvinyl acetal resin layer (A) and a thermoplastic resin layer (B), wherein the polyvinyl acetal resin in the layer (A) is at 20 ° C. using a Brookfield type (B type) viscometer. The viscosity of a 10 mass% toluene / ethanol = 1/1 (mass ratio) solution measured at 30 rpm is greater than 200 mPa · s, and the amount of plasticizer in the layer (A) is The layer (A) has a thickness of 10 to 350 μm, and the resin material constituting the layer (B) has a tensile storage modulus E ′ (40) and 40 ′ at 40 ° C. A laminated film having a tensile storage modulus E ′ (100) at ° C. satisfying the formulas (1) and (2).
(1) E '(40) ≧ 1000 MPa
(2) E '(100) ≧ 10 MPa
The difference in the refractive index between the refractive index of the layer (A) and the refractive index of the layer (B) measured based on ASTM D542 is 0.10 or less, and the laminated glass in which the laminated film is sandwiched between two glasses. The laminated film according to claim 1, wherein a haze value based on JIS # K7136 is 1.5% or less.
The laminated film according to claim 1 or 2, wherein the thickness of the layer (B) is 150 µm or less.
The laminated film according to any one of claims 1 to 3, wherein the resin material constituting the layer (B) has a tensile storage elastic modulus E '(120) at 120 ° C that satisfies the formula (3).
(3) E ′ (120) ≦ 500 MPa
The laminated film according to any one of claims 1 to 4, wherein the arithmetic average roughness (Ra) of at least one surface of the layer (B) is 0.15 μm or less.
The laminated film according to any one of claims 1 to 5, wherein the layer (B) contains metal oxide fine particles having a heat ray shielding function.
The laminated film according to any one of claims 1 to 6, further comprising another polyvinyl acetal resin layer (C).
(8) The laminated film according to any one of (1) to (7), further comprising a functional layer (D).
The laminated film according to claim 8, wherein the layer (D) is a heat ray shielding coating layer having a thickness of 0.01 to 200 μm.
積層 The laminated film according to claim 8 or 9, wherein the layer (D) is a conductive structure.
The laminated film according to claim 10, wherein the conductive structure is formed by a printing method, an etching method, or a vapor deposition method.
The laminated film according to claim 10, wherein the conductive structure contains at least one conductive material selected from the group consisting of gold, silver, copper, and metal oxide.
The laminated film according to any one of claims 1 to 12, wherein the layer (A) contains metal oxide fine particles having a heat ray shielding function.
(14) A laminated film with a protective film, comprising a peelable protective film on the outermost layer of the laminated film according to any one of (1) to (13).
A laminated glass in which the laminated film according to any one of claims 1 to 13 or the laminated film obtained by peeling the protective film from the laminated film with the protective film according to claim 14 is sandwiched between two glasses.