TW202313886A - Adhesive film and laminate - Google Patents

Abstract

This adhesive film includes a thermoplastic resin, does not include a plasticizer or includes less than 20 parts by mass of a plasticizer per 100 parts by mass of the thermoplastic resin, has a shear storage modulus of 3*10<SP>5</SP> Pa or greater at 20 DEG C, and has an adhesive force of 100 N or greater to a polycarbonate substrate as measured according to the following method.

Description

Adhesive film, and laminate

The present invention relates to an adhesive film and a laminate with the adhesive film.

In various displays such as liquid crystal displays, organic EL displays, and displays with touch panels, in order to overlap and fix surface protection panels, polarizers, films with touch sensors, glass with touch sensors, etc., And widely used with adhesive film. As an adhesive film, (meth)acrylic resin has conventionally been widely used from viewpoints, such as transparency and adhesiveness. In addition, the use of polyvinyl acetal resins other than (meth)acrylic resins is also being studied.

When polyvinyl acetal-based resin is used, for example, as disclosed in Patent Documents 1 and 2, it is known to use a plasticized polyvinyl acetal-based resin in which a certain amount or more of a plasticizer is blended. In addition, it is also being studied to incorporate a reactive diluent that hardens by light irradiation into the plasticized polyvinyl acetal resin so that the storage modulus can be increased by light irradiation.

In addition, in recent years, attempts have been made to introduce a light-adjustable film into laminated glass constituting window glass so that light transmission and the like can be adjusted. In the case of introducing a light-adjusting film, laminated glass is known to have, for example, a structure in which a light-adjusting film is placed between two glass plates, and the light-adjusting film and each glass plate are bonded with a resin film interposed therebetween. The application of adhesive films containing plasticized polyvinyl acetal resins to resin films is being studied. [Prior Art Literature] [Patent Document]

Patent Document 1: Japanese Patent No. 6046811 Patent Document 2: Japanese Patent No. 6116772

[Problem to be Solved by the Invention]

Furthermore, various displays, especially those with touch panels, are widely used in vehicle applications such as car navigation systems. In addition, studies have been made to use the laminated glass with the light-adjusting film introduced as window glass for vehicles such as automobiles. When a display is used in a car, or a laminated glass incorporating a light-adjusting film is used as a window glass for a vehicle, it is necessary to ensure that the display or window glass is not easily damaged even if it receives a strong impact in a collision accident. sex. In addition, when the adhesive film is used for a display or laminated glass incorporating a light-adjusting film, it is necessary to improve the compatibility of various resin materials constituting polarizers, films with touch sensors, and light-adjusting films. Continuity.

However, conventional (meth)acrylic resin films that have been widely used as adhesive films have a problem of low crash safety such that displays or window glass are easily broken in the event of a collision accident or the like. On the other hand, although the plasticized polyvinyl acetal resin has good collision safety, when a plasticizer or a reactive diluent is mixed with a plasticizer or a reactive diluent during long-term storage, there may be "plasticizer and reactive diluent" in the exudation property. The problem of the permeation of the permanent thinner and the contamination of the surrounding components, etc. In addition, it is difficult for plasticized polyvinyl acetal-based resins to sufficiently improve the adhesiveness to various resin materials, especially resin materials with low polarity.

Therefore, an object of the present invention is to improve the adhesion to various resin films and improve the collision safety and bleeding properties in an adhesive film made of a thermoplastic resin such as polyvinyl acetal resin. [Technical means to solve the problem]

（式（1）中，A ¹O為碳數2～6之氧伸烷基，m為平均重複數，為4～200；R ¹為碳數1～8之烷基或氫原子；再者，氧伸烷基可為單獨1種，亦可混合存在2種以上；*為與其他基之鍵結位置） [7]如上述[5]記載之黏著膜，其中，上述聚乙烯縮醛系樹脂具有聚環氧烷結構。 [8]如上述[6]或[7]記載之黏著膜，其中，上述聚環氧烷結構包含氧伸乙基及氧伸丙基之至少任一者。 [9]如上述[6]至[8]中任一項記載之黏著膜，其中，上述聚環氧烷結構係經由單鍵、或醚鍵、酯鍵、醯胺鍵、及可具有該等鍵中之至少任一者之烴基之任一者而連結於主鏈。 [10]如上述[6]至[9]中任一項記載之黏著膜，其中，利用上述聚環氧烷結構之改質量為0.1莫耳%以上10莫耳%以下。 [11]如上述[5]至[10]中任一項記載之黏著膜，其中，上述聚乙烯縮醛系樹脂之縮醛化度為40莫耳%以上90莫耳%以下。 [12]如上述[5]至[11]中任一項記載之黏著膜，其中，上述聚乙烯縮醛系樹脂之羥基量為5莫耳%以上35莫耳%以下。 [13]如上述[5]至[12]中任一項記載之黏著膜，其中，上述聚乙烯縮醛系樹脂之乙醯化度為0.01莫耳%以上50莫耳%以下。 [14]如上述[5]至[13]中任一項記載之黏著膜，其中，上述聚乙烯縮醛系樹脂為聚乙烯縮丁醛系樹脂。 [15]如上述[5]至[14]中任一項記載之黏著膜，其中，上述聚乙烯縮醛系樹脂之重量平均分子量（Mw）為50,000以上800,000以下。 [16]如上述[5]至[15]中任一項記載之黏著膜，其中，上述聚乙烯縮醛系樹脂之含量以黏著膜所含有之熱塑性樹脂總量為基準，為50質量%以上100質量%以下。 [17]如上述[1]至[16]中任一項記載之黏著膜，其不含有分子量未達1000之低分子量化合物、或相對於上述熱塑性樹脂100質量份含有未達20質量份之分子量未達1000之低分子量化合物。 [18]如上述[1]至[17]中任一項記載之黏著膜，其中，上述塑化劑為選自由有機酯塑化劑、有機磷系塑化劑、有機醚系塑化劑、及醇系塑化劑所組成之群中之至少1種。 [19]如上述[1]至[18]中任一項記載之黏著膜，其中，上述黏著膜包含選自由二醇與一元性有機酸之酯、及碳數4～12之二元性有機酸與碳數4～10之醇之酯化合物、聚伸烷基二醇（polyalkylene glycol）系塑化劑、及聚氧伸烷基醚（polyoxyalkylene ether）系塑化劑所組成之群中之至少1種作為塑化劑。 [20]一種積層體，其具備上述[1]至[19]中任一項記載之黏著膜、與無機材料基材及有機材料基材之至少任一者。 [21]如上述[20]記載之積層體，其中，上述黏著膜係以接著於無機材料基材及有機材料基材之至少任一者之方式配置。 [22]如上述[20]或[21]記載之積層體，其中，上述無機材料基材係選自由無機玻璃板、以及附有電極或感測器之至少任一者之無機玻璃板所組成之群。 [23]如上述[20]至[22]中任一項記載之積層體，其中，上述有機材料基材係選自由聚碳酸酯板、（甲基）丙烯酸（（meth）acrylate）板、以及聚對苯二甲酸乙二酯膜、環狀聚烯烴膜、聚碳酸酯膜、及於該等膜附有電極或感測器之至少任一者之膜所組成之群。 [24]如上述[20]至[23]中任一項記載之積層體，其具備選自無機材料基材及有機材料基材之一對基材、以及配置於上述一對基材之間之上述黏著膜，並且，該積層體為3層以上之多層結構。 [25]如上述[24]記載之積層體，其具備配置於上述一對基材之間之中間構件、及配置於各基材與上述中間構件之間之接著用膜，上述接著用膜之至少任一者為上述黏著膜。 [26]如上述[25]記載之積層體，其中，在上述中間構件之接著上述黏著膜之位置處配置無機材料基材、及有機材料基材之至少任一者。 [27]如上述[25]或[26]記載之積層體，其中，上述中間構件為觸控面板及調光元件之任一者。 [28]如上述[20]至[27]中任一項記載之積層體，其中，上述無機材料基材及有機材料基材之至少任一者構成觸控面板、調光元件、及顯示元件之至少一部分。 [29]一種顯示器，其包含上述[20]至[28]中任一項記載之積層體。 [30]一種層合玻璃，其包含上述[20]至[28]中任一項記載之積層體。 [31]一種上述[1]至[19]中任一項記載之黏著膜之用途，其係用於顯示器。 [32]一種上述[1]至[19]中任一項記載之黏著膜之用途，其係用於層合玻璃。 [發明之效果] The inventors of the present invention conducted active research and found that by reducing the content of the plasticizer in an adhesive film containing a thermoplastic resin, the storage modulus and the polycarbonate-based The adhesive strength of the material is more than a specific value, the above-mentioned problems can be solved, and the following invention has been completed. That is, the present invention provides the following [1] to [32]. [1] An adhesive film comprising a thermoplastic resin, which does not contain a plasticizer, or contains less than 20 parts by mass of a plasticizer relative to 100 parts by mass of the thermoplastic resin, wherein the adhesive film is stored under shear at 20°C The modulus is 3×10 ⁵ Pa or more, and the adhesion force to the polycarbonate substrate measured by the following method is 100 N or more. <Measurement method of adhesive force> Prepare an adhesive film with a size of 15 mm in length and 15 mm in width, and two polycarbonate plate glasses with a thickness of 2 mm, a length of 25 mm, and a width of 100 mm according to JIS K6735; Two pieces of polycarbonate plate glass are arranged in such a way that the longitudinal direction of each other is perpendicular to each other that they are stacked to form a cross; then, in such a way that the thickness of the above-mentioned adhesive film is fixed, a spacer with the same thickness as the above-mentioned adhesive film is used. In the assembly machine, the two pieces of polycarbonate plate glass overlapped through the above adhesive film are temporarily pressed for 3 minutes under the conditions of 90°C and 0.1 MPa; then, the two pieces of temporarily pressed polycarbonate plate glass are placed in the Under the conditions of 90°C and 0.5 MPa, the formal pressure bonding was carried out for 1 hour to obtain a laminated glass sample; for the obtained laminated glass sample, at a temperature of 23°C, in the direction perpendicular to the bonding surface at a speed of 10 mm/min Peel off one piece of polycarbonate plate glass from another piece of polycarbonate plate glass, measure the maximum load (N) at this time, and use this maximum load (N) as the adhesive force. [2] The adhesive film according to the above [1], wherein the maximum peak temperature of tan δ at -50°C to 150°C is 10°C to 52°C. [3] The adhesive film according to the above [1] or [2], which has a thickness of not less than 100 μm and not more than 2000 μm. [4] The adhesive film according to any one of the above [1] to [3], which has a thickness of not less than 100 μm and not more than 1000 μm. [5] The adhesive film according to any one of the above [1] to [4], wherein the thermoplastic resin is a polyvinyl acetal resin. [6] The adhesive film according to the above [5], wherein the polyvinyl acetal resin has a polyalkylene oxide structure represented by the following formula (1).

(In formula (1), A ¹ O is an oxyalkylene group with 2 to 6 carbons, m is the average repetition number, which is 4 to 200; R ¹ is an alkyl group with 1 to 8 carbons or a hydrogen atom; and , the oxyalkylene group can be a single type, or two or more types can be mixed; * is the bonding position with other groups) [7] The adhesive film as described in the above [5], wherein the above-mentioned polyvinyl acetal The resin has a polyalkylene oxide structure. [8] The adhesive film according to the above [6] or [7], wherein the polyalkylene oxide structure contains at least any one of an oxyethylene group and an oxypropylene group. [9] The adhesive film according to any one of the above-mentioned [6] to [8], wherein the polyalkylene oxide structure is via a single bond, or an ether bond, an ester bond, an amide bond, and may have such Any one of the hydrocarbon groups in at least one of the bonds is linked to the main chain. [10] The adhesive film according to any one of the above [6] to [9], wherein the amount of modification by the polyalkylene oxide structure is 0.1 mol% or more and 10 mol% or less. [11] The adhesive film according to any one of the above [5] to [10], wherein the degree of acetalization of the polyvinyl acetal-based resin is not less than 40 mol % and not more than 90 mol %. [12] The adhesive film according to any one of [5] to [11] above, wherein the amount of hydroxyl groups in the polyvinyl acetal-based resin is not less than 5 mol % and not more than 35 mol %. [13] The adhesive film according to any one of [5] to [12] above, wherein the degree of acetylation of the polyvinyl acetal resin is 0.01 to 50 mol%. [14] The adhesive film according to any one of the above [5] to [13], wherein the polyvinyl acetal-based resin is a polyvinyl butyral-based resin. [15] The adhesive film according to any one of the above [5] to [14], wherein the polyvinyl acetal resin has a weight average molecular weight (Mw) of 50,000 to 800,000. [16] The adhesive film according to any one of [5] to [15] above, wherein the content of the polyvinyl acetal resin is 50% by mass or more based on the total amount of thermoplastic resin contained in the adhesive film 100% by mass or less. [17] The adhesive film according to any one of [1] to [16] above, which does not contain a low-molecular-weight compound with a molecular weight of less than 1000, or contains a molecular weight compound of less than 20 parts by mass relative to 100 parts by mass of the above-mentioned thermoplastic resin. Low molecular weight compounds less than 1000. [18] The adhesive film according to any one of [1] to [17] above, wherein the plasticizer is selected from organic ester plasticizers, organophosphorus plasticizers, organic ether plasticizers, and at least one of the group consisting of alcohol-based plasticizers. [19] The adhesive film according to any one of the above [1] to [18], wherein the adhesive film contains esters of diols and monobasic organic acids, and binary organic acids having 4 to 12 carbon atoms. At least one of ester compounds of acids and alcohols with 4 to 10 carbon atoms, polyalkylene glycol (polyalkylene glycol) plasticizers, and polyoxyalkylene ether (polyoxyalkylene ether) plasticizers 1 as a plasticizer. [20] A laminate comprising the adhesive film described in any one of [1] to [19] above, and at least any one of an inorganic material substrate and an organic material substrate. [21] The laminate according to the above [20], wherein the adhesive film is arranged so as to adhere to at least one of the inorganic material base material and the organic material base material. [22] The laminate according to the above [20] or [21], wherein the inorganic material substrate is selected from an inorganic glass plate and an inorganic glass plate with at least one of electrodes or sensors attached thereto group. [23] The laminate according to any one of the above [20] to [22], wherein the organic material substrate is selected from polycarbonate plates, (meth)acrylic ((meth)acrylate) plates, and A group consisting of a polyethylene terephthalate film, a cyclic polyolefin film, a polycarbonate film, and a film having at least any one of electrodes or sensors attached to these films. [24] The laminate according to any one of the above [20] to [23], comprising a pair of substrates selected from inorganic material substrates and organic material substrates, and a substrate disposed between the pair of substrates. The above-mentioned adhesive film, and the laminate has a multilayer structure of 3 or more layers. [25] The laminate according to the above [24], which includes an intermediate member arranged between the pair of base materials, and an adhesive film arranged between each base material and the intermediate member, wherein the adhesive film At least any one is the above-mentioned adhesive film. [26] The laminate according to [25] above, wherein at least one of an inorganic material base material and an organic material base material is disposed at a position of the intermediate member adjacent to the adhesive film. [27] The laminate according to the above [25] or [26], wherein the intermediate member is any one of a touch panel and a light control element. [28] The laminate according to any one of the above [20] to [27], wherein at least one of the above-mentioned inorganic material base material and organic material base material constitutes a touch panel, a dimming element, and a display element at least part of it. [29] A display comprising the laminate according to any one of [20] to [28]. [30] A laminated glass comprising the laminate according to any one of [20] to [28]. [31] A use of the adhesive film according to any one of the above-mentioned [1] to [19], which is used for a display. [32] A use of the adhesive film according to any one of the above [1] to [19] for laminating glass. [Effect of Invention]

According to the present invention, in an adhesive film containing a thermoplastic resin, the adhesiveness to various resin materials can be improved, and the collision safety and bleeding properties can be improved.

<Adhesive Film> The adhesive film of the present invention contains a thermoplastic resin and does not contain a plasticizer, or contains less than 20 parts by mass of a plasticizer relative to 100 parts by mass of a thermoplastic resin. The number is 3×10 ⁵ Pa or more, and the adhesive force to the polycarbonate substrate measured under specific measurement conditions is 100 N or more. The adhesive film of the present invention can improve the adhesiveness to various resin films by having the above-mentioned configuration, and can also improve the collision safety and bleeding properties.

Hereinafter, the adhesive film which concerns on one embodiment of this invention is demonstrated in detail. [Shear Storage Modulus] The adhesive film of the present invention has a shear storage modulus of 3×10 ⁵ Pa or more at 20°C. If the shear storage modulus is less than 3×10 ⁵ Pa, when the laminate obtained by bonding the adhesive film is subjected to a high impact, the adhesive film will be greatly deformed, resulting in a large sinking amount of the laminate. Therefore, the laminated body including the adhesive film is prone to breakage, and the crash safety is reduced. From the standpoint of reducing the amount of subsidence of the laminate and improving crash safety even under a relatively high impact, the above-mentioned shear storage modulus at 20°C is preferably 1×10 ⁶ Pa or more, more preferably 5× 10 ⁶ Pa or more, more preferably 1×10 ⁷ Pa or more, still more preferably 2×10 ⁷ Pa or more.

From the viewpoint of crash safety, it is preferable that the shear storage modulus of the adhesive film at 20°C be high, but from the viewpoint of improving other physical properties with a good balance, for example, 5×10 ⁹ Pa or less is preferable. It is 1×10 ⁹ Pa or less, more preferably 8×10 ⁸ Pa or less. Furthermore, the shear storage modulus can be measured by using a dynamic viscoelasticity measuring device at a frequency of 1 Hz, performing viscoelasticity measurement in a shear mode, and detecting the storage modulus (G') at 20°C.

[adherence] The adhesion force of the adhesive film of the present invention to the polycarbonate substrate measured under specific measurement conditions is above 100 N. The polycarbonate substrate has low polarity and is not easily adhered to the resin constituting the adhesive film, such as polyvinyl acetal resin. The adhesive force of the material becomes higher. On the other hand, if the above-mentioned adhesive force is less than 100 N, the adhesive force of the adhesive film to various resins may become insufficient. From the viewpoint of further improving the adhesive force to various resins, the above-mentioned adhesive force is preferably 200 N or more. In addition, the higher the above-mentioned adhesive force, the better, but it is usually 1000 N or less, and may be 600 N or less.

The above-mentioned method for measuring the adhesive force of polycarbonate substrates is carried out for "the laminated glass samples obtained through the following steps 1, 2 and 3 in sequence". Step 1: Prepare an adhesive film with a size of 15 mm in length and 15 mm in width, and two pieces of polycarbonate plate glass with a thickness of 2 mm, a length of 25 mm, and a width of 100 mm according to JIS K6735. Then, two sheets of polycarbonate plate glass were arranged so that the longitudinal directions of each other were perpendicular to each other through an adhesive film, and were stacked to form a cross. Step 2: In such a way that the thickness of the adhesive film is fixed, use a spacer with the same thickness as the adhesive film, and place two pieces of polycarbonate plate glass overlapping with the adhesive film in a vacuum laminating machine at 90°C and 0.1 Under the condition of MPa, perform temporary crimping for 3 minutes. Step 3: The temporarily crimped 2 pieces of polycarbonate plate glass were crimped under the conditions of 90°C and 0.5 MPa for 1 hour to obtain a laminated glass sample.

Then, a cross-peel test was performed on the obtained laminated glass samples. Specifically, in an environment of 23°C, one piece of polycarbonate plate glass is peeled from another piece of polycarbonate plate glass at a speed of 10 mm/min in the direction perpendicular to the bonding surface, and the maximum load (N) at this time is measured. This maximum load (N) is used as the adhesion force. More specifically, it only needs to be placed in the jig shown in Figure 5 to measure the adhesive force. The jig is composed of a box body 11 and a pressing member 20 . The case 11 and the pressing member 20 are made of SUS. The box body 11 is a cuboid with an open upper surface, and rectangular notches 14, 14 are arranged on the upper end faces of the opposite side surfaces 13, 13. The pressing member 20 is a U-shaped member, and is provided with a rectangular base portion 16 and pressing pieces 17, 17 connected at right angles to both ends of the base portion 16 in the longitudinal direction. The width W of each pressing piece 17 is 20 mm, the thickness T is 5 mm, and the distance L between the pressing pieces 17 and 17 is 35 mm. Regarding the laminated glass sample 10 , another polycarbonate plate glass 21 was placed between the notches 14 and 14 so that one polycarbonate plate 22 was placed on the lower side. Peel off the polycarbonate plate glass 21 by applying a load in the direction perpendicular to the bonding surface, that is, vertically downward X, at a speed of 10 mm/min. Measure the maximum load (N) at this time, and obtain the bonding force based on the maximum load (N) (N). Furthermore, the adhesive force (N) refers to the adhesive force per 225 mm ² area.

[The maximum peak temperature of tanδ] In the present invention, the maximum peak temperature of tanδ of the adhesive film is preferably not less than 10°C and not more than 52°C. If the maximum peak temperature of tan δ is 52° C. or lower, the resin film becomes sufficiently flexible, and the adhesiveness to various resin materials or inorganic glass can be improved. From the viewpoint of improving flexibility and improving adhesiveness, the maximum peak temperature of tan δ of the resin composition is preferably 48°C or lower, more preferably 44°C or lower, and still more preferably 40°C or lower. Also, when the maximum peak temperature of tan δ is 10° C. or higher, it is easy to prevent the coalescence of the adhesive film, and it is possible to prevent a decrease in handleability. The maximum peak temperature of tanδ of the resin composition is preferably at least 12°C, more preferably at least 20°C. Furthermore, the maximum peak temperature of tan δ of the resin film can be detected by the following method: use a dynamic viscoelasticity measuring device to perform viscoelasticity measurement, and read the peak temperature of the loss tangent tan δ obtained from the result of the viscoelasticity measurement at which tan δ reaches the maximum value of the peak temperature.

Furthermore, the above-mentioned shear storage modulus, adhesive force, and maximum peak temperature of tan δ can be adjusted by properly selecting the type of resin, the molecular weight of the resin, the presence or absence of blended plasticizer and its content.

[thermoplastic resin] Examples of thermoplastic resins used in adhesive films include (meth)acrylic resins, polyvinyl acetal resins, polyvinyl alcohol resins (PVA), polyurethane resins (PU), ethylene- Vinyl acetate copolymer resin (EVA), ethylene-vinyl acetate copolymer saponified product (EVOH), ethylene-methacrylic acid copolymer resin, ionomer resin, isobutylene resin, styrene-isoprene copolymer resin , Styrene-butadiene copolymer resin, etc. In the adhesive film, one type of thermoplastic resin may be used alone, or two or more types may be used in combination. Among the above, the thermoplastic resin is preferably polyvinyl acetal resin. By using polyvinyl acetal resin, it becomes easy to improve the adhesive force to various resins, and also improves the collision safety. Hereinafter, the polyvinyl acetal resin used for the thermoplastic resin will be described in detail.

[polyvinyl acetal resin] As mentioned above, the thermoplastic resin is preferably polyvinyl acetal-based resin. The polyvinyl acetal resin may be a modified polyvinyl acetal resin or an unmodified polyvinyl acetal resin. The modified polyvinyl acetal resin is as follows, as long as it has a structure (modifying group) other than an acetal group, a hydroxyl group, and an acetyl group, it is preferable to have a modifying group in a side chain. The polyvinyl acetal-based resin is obtained by acetalizing polyvinyl alcohol with aldehyde, and reacting with a modifier as necessary, or performing a re-acetylation treatment. Moreover, in order to obtain a modified polyvinyl acetal resin, modified polyvinyl alcohol can also be used as a raw material polyvinyl alcohol.

The above-mentioned structures other than acetal group, hydroxyl group, and acetyl group are preferably polyalkylene oxide structures. Specifically, the polyalkylene oxide structure is represented by the following formula (1).

（式（1）中，A ¹O為碳數2～6之氧伸烷基，m為平均重複數，為4～200。R ¹為碳數1～8之烷基或氫原子。再者，氧伸烷基可為單獨1種，亦可混合存在2種以上。*為與其他基之鍵結位置）

(In formula (1), A ¹ O is an oxyalkylene group with 2 to 6 carbons, m is the average repetition number, which is 4 to 200. ^{R 1} is an alkyl group with 1 to 8 carbons or a hydrogen atom. Furthermore , the oxyalkylene group can be a single type, or two or more types can be mixed. * is the bonding position with other groups)

The oxyalkylene group in A ¹ O is an oxyalkylene group having 2 to 6 carbons, preferably an oxyalkylene group having 2 to 4 carbons, more preferably an oxyalkylene group having 2 or 3 carbons. When the carbon number of the oxyalkylene group is within the above range, it becomes easy to increase the shear storage modulus to improve the impact safety of the adhesive film, and to improve the adhesive force to various resin materials such as polycarbonate. The alkylene group in the oxyalkylene group may be a straight chain or may have a branched structure. As the oxyalkylene group, for example, an oxyethylene group, an oxypropylene group, or an oxybutylene group may be mentioned, and an oxyethylene group or an oxypropylene group is preferred. An oxyalkylene group may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types together, each oxyalkylene group may add randomly, and may add in blocks, but it is more preferable to add randomly.

The oxyalkylene group in the polyalkylene oxide structure preferably includes at least any one of an oxyethylene group and an oxypropylene group, and also preferably includes both an oxyethylene group and an oxypropylene group. When both oxyethylidene and oxypropylidene groups are included, they may form a block structure, but preferably form a random structure. When including oxyethylene (EO) and oxypropylene (PO), the ratio of oxypropylene to oxypropylene (PO/EO) is in molar ratio, for example, 1/9 or more 9/1 or less, preferably 2/8 or more and 8/2 or less, more preferably 3/7 or more and 7/3 or less.

In formula (1), m represents the average repetition number of the oxyalkylene group, and it is 4-200, Preferably it is 5-100, More preferably, it is 10-80, More preferably, it is 15-50. In addition, the alkyl group in R ¹ may be a straight chain or may have a branched structure. As the alkyl group in ^R , for example: methyl, ethyl, n-propyl, isopropyl, n-butyl, second butyl, third butyl and other branched butyl, n-pentyl, branched pentyl, etc. Base, n-hexyl, branched hexyl, n-heptyl, isoheptyl, 3-heptyl and other branched heptyls, n-octyl, isooctyl, 2-ethylhexyl and other branched octyls, etc. R ¹ is preferably an alkyl group with 1 to 6 carbons or a hydrogen atom, more preferably an alkyl group with 1 to 4 carbons or a hydrogen atom.

The above-mentioned polyalkylene oxide structure may be linked to the main chain via a single bond, but is preferably linked to the main chain via a linking group other than a single bond. As a linking group other than a single bond, for example: an ether bond (-O-), an ester bond (-COO-), an amide bond (-CONR-: R is a hydrogen atom or an alkyl group with 1 to 4 carbons, preferably a hydrogen atom), or a hydrocarbon group which may have at least any of these bonds. Among these, an ether bond (—O—), an ester bond (—COO—), or a hydrocarbon group which may have at least any one of these bonds is more preferable. The carbon number of the hydrocarbon group is not particularly limited, for example, about 1-10, preferably 1-4. Moreover, among these, it is more preferable that the above-mentioned polyalkylene oxide structure is bonded to the main chain via either an ether bond or _-CH2O- . The polyalkylene oxide structure is easily produced by being bonded to the main chain through any of them. In addition, in _-CH2O- , an oxygen atom may be bonded to the said polyalkylene oxide structure.

A polyvinyl acetal resin typically has an acetal group, a hydroxyl group, and an acetyl group. However, the polyvinyl acetal resin may not contain a hydroxyl group because it is modified by a functional group or undergoes a reacetylation reaction. Furthermore, the acetal group, hydroxyl group, and acetyl group, as shown in the following formulas (3-1) to (3-3), are groups bonded to the main chain directly or through oxygen atoms, excluding polyepoxide groups. The hydroxyl group of the alkane structure, etc. Moreover, it is preferable that polyvinyl acetal-type resin has the polyalkylene oxide structure represented by said formula (1) as mentioned above by modification. In addition, below, in order to distinguish and demonstrate the polyvinyl acetal resin which has a polyalkylene oxide structure from other polyvinyl acetal resin, it may demonstrate as modified polyvinyl acetal resin (A).

The modification amount of the modified polyvinyl acetal resin (A) utilizing the polyalkylene oxide structure (ie, the functional group represented by the formula (1)) is preferably 0.1 mol% or more and 10 mol% or less. If the above-mentioned modified amount is within the above-mentioned range, the shear storage modulus at 20° C. becomes high, and the collision safety can be improved. In addition, the maximum peak temperature of tan δ tends to be lowered, which can improve the adhesion of the adhesive film to various resin materials such as polycarbonate. From these points of view, the amount of modification using the polyalkylene oxide structure is preferably at least 0.2 mol %, more preferably at least 0.3 mol %, further preferably at least 0.4 mol %, especially preferably 0.5 mol % % or more, and preferably at most 8 mol%, more preferably at most 6 mol%, further preferably at most 4 mol%.

In addition, the modification amount by a functional group shows the ratio of a functional group with respect to the whole vinyl monomer unit which comprises polyvinyl acetal resin. The proton NMR measurement can be performed on the polyvinyl acetal resin, and the modified amount can be calculated from the obtained spectrum. The degree of acetalization, the amount of hydroxyl groups, and the degree of acetylation described below can also be measured by proton NMR in the same manner, and calculated from the obtained spectra.

The polyvinyl acetal resin does not need to have the said polyalkylene oxide structure. Such a polyvinyl acetal resin may be a modified polyvinyl acetal resin having a modifying group other than the functional group represented by formula (1), or may be an unmodified polyvinyl acetal resin. Even if it is unmodified polyvinyl acetal resin, the number of hydroxyl groups is reduced as follows by reacetylation reaction, etc., so that it becomes easy to lower the maximum peak temperature of tanδ, and improve the adhesion to various resin materials.

As a modifying group other than the functional group represented by formula (1), an alkyl group is mentioned. The alkyl group may be a straight chain or may have a branched structure. The carbon number of the alkyl group is, for example, 2-30, preferably 3-24, more preferably 5-20, further preferably 7-18, further preferably 11-18. The alkyl group can be directly bonded to the main chain, preferably directly bonded to the vinyl-derived structural unit constituting the main chain, but preferably through an ether bond (-O-), an ester bond (*-COO-* *), urethane bond (urethane bond, *-NHCOO-**) bond, more preferably via ester bond or urethane bond. Furthermore, in the ester bond and the urethane bond, "*" and "**" are bonded to the alkyl group or the bonding position of the main chain. Among the bonds, "*" is preferably bonded to the alkyl group. Bonding position, "**" is the bonding position on the main chain.

The polyvinyl acetal-based resin has a vinyl-derived structural unit as a main chain, and the functional group represented by formula (1) may be bonded to the vinyl-derived structural unit constituting the main chain. Therefore, the polyvinyl acetal resin preferably has a structural unit represented by the following formula (2), and more preferably has any of the structural units represented by the following formula (2-1) and formula (2-2). one.

（式（2）中，A ¹O、R ¹、m與上述相同。R ²為單鍵、或可具有酯鍵或醚鍵之至少任一者之烴基之任一者）

(In formula (2), A ¹ O, R ¹ , and m are the same as above. ^{R 2} is any one of a single bond, or a hydrocarbon group which may have at least one of an ester bond or an ether bond)

（式（2-1）、（2-2）中，A ¹O、R ¹、m係與上述相同）

(In formulas (2-1) and (2-2), A ¹ O, R ¹ , and m are the same as above)

A ¹ O, R ¹ , and m in the formulas (2), (2-1), and (2-2) are as described above, and therefore their explanations are omitted. The carbon number of R ² in the formula (2) is, for example, 1-10, preferably 1-4. As mentioned above, the hydrocarbon group of ^R2 may have an ester bond or an ether bond, but preferably does not have an ester bond or an ether bond.

Polyvinyl acetal resins typically have acetal groups, hydroxyl groups, and acetyl groups, that is, polyvinyl acetal resins typically have the following formula (3-1), formula (3-2) and The structural unit shown in formula (3-3). Therefore, the modified polyvinyl acetal resin preferably has the structural units represented by the following formula (3-1), formula (3-2) and formula (3-3), and the structural unit represented by the above formula (2) Structural units. However, when the polyvinyl acetal-based resin is, for example, an unmodified polyvinyl acetal resin, etc., as described above, it does not need to have a hydroxyl group, and does not need to have the structural unit represented by the formula (3-2). That is, the unmodified polyvinyl acetal resin may have the structural units represented by the following formula (3-1) and formula (3-3), and may further optionally have the structure represented by the following formula (3-2) unit.

（式（3-1）中，R表示氫原子或碳數1～19之烴基）

(In formula (3-1), R represents a hydrogen atom or a hydrocarbon group with 1 to 19 carbons)

As mentioned above, polyvinyl acetal-based resin is obtained by acetalizing polyvinyl alcohol or modified polyvinyl alcohol obtained by modifying polyvinyl alcohol with aldehyde, and then modifying it if necessary. As polyvinyl alcohol, polyvinyl alcohol having an alkalization degree of 80 to 99.8 mol % is generally used.

The number of carbon atoms in the acetal group contained in the polyvinyl acetal resin is not particularly limited, and as shown in the above formula (3-1), it is, for example, 1 to 20, preferably 2 to 10, more preferably 2 to 6, more preferably 2, 3 or 4. Therefore, the carbon number of R represented by the above formula (3-1) is preferably 1-9, more preferably 1-5, and still more preferably 1-3. Specifically, as the acetal group, a butyral group is particularly preferable, and therefore, as the polyvinyl acetal-based resin, a polyvinyl butyral-based resin is preferable. The degree of acetalization (that is, the amount of acetal) of the polyvinyl acetal-based resin is preferably from 40 mol % to 90 mol %. Also, the degree of acetalization is more preferably at least 55 mol%, more preferably at least 60 mol%, and more preferably at most 88 mol%, even more preferably at most 85 mol%. When the degree of acetalization is within the above-mentioned range, it becomes easy to make the amount of hydroxyl groups moderate, and to contain a certain amount of functional groups represented by the formula (1). Furthermore, the so-called degree of acetalization means the degree of acetalization when the acetal group of the polyvinyl acetal resin is an acetoacetal group, and when the acetal group is a butyral group In the case of , it means the degree of butyralization. Moreover, the degree of acetalization shows the ratio of the acetalized vinyl alcohol unit with respect to the whole vinyl monomer unit which comprises polyvinyl acetal resin.

The amount of hydroxyl groups in the polyvinyl acetal resin is preferably at most 35 mol%, more preferably at most 33 mol%, further preferably at most 30 mol%. When the amount of hydroxyl groups is not more than the above upper limit, it becomes easy to make the maximum peak temperature of tan δ an appropriate value, and it becomes easy to improve the adhesive force to resin materials with low polarity such as polycarbonate. Also, the amount of hydroxyl groups in the polyvinyl acetal resin may be 0 mol% or more, but in the case of the modified polyvinyl acetal resin (A), from the viewpoint of preventing the adhesive film from becoming too soft, it may contain A certain amount of hydroxyl groups is, for example, 5 mol% or more, preferably 9 mol% or more, more preferably 10 mol% or more, and more preferably 12 mol% or more.

Also, when the polyvinyl acetal resin is unmodified polyvinyl acetal resin, for example, in order to lower the maximum peak temperature of tan δ and improve the adhesion to resins with low polarity such as polycarbonate, it is necessary to reduce the amount of hydroxyl groups . Therefore, the hydroxyl content of the unmodified polyvinyl acetal resin is preferably less than 15 mol%, more preferably less than 10 mol%, further preferably less than 5 mol%, and even more preferably less than 3 mol%. , the best is 0 mole%. In addition, the amount of a hydroxyl group shows the ratio of a hydroxyl group with respect to the whole vinyl monomer unit which comprises a polyvinyl acetal resin.

The degree of acetylation (the amount of acetyl groups) of the above-mentioned polyvinyl acetal-based resin is, for example, 0.01 to 50 mol%, but in the case of modified polyvinyl acetal resin (A), in order to make the utilization It is preferable that the modified amount of the functional group represented by the formula (1) is above a certain value, and the degree of acetylation is also below a certain value. Therefore, the degree of acetylation of the modified polyvinyl acetal resin (A) is preferably less than 20 mol%, more preferably less than 15 mol%, further preferably less than 12 mol%, and even more preferably 5 mol%. Mole % or less. Also, the degree of acetylation of the modified polyvinyl acetal resin (A) is as described above, for example, not less than 0.01 mol%, but preferably not less than 0.1 mol%, more preferably not less than 0.3 mol%.

Also, from the perspective of reducing the amount of hydroxyl groups, reducing the maximum peak temperature of tanδ, and improving the adhesion to resins with low polarity such as polycarbonate, in the case of unmodified polyvinyl acetal resin, its acetylation The concentration is preferably at least a certain value, preferably at least 15 mol%, more preferably at least 25 mol%, and still more preferably at least 30 mol%. Also, the degree of acetylation of the unmodified polyvinyl acetal resin is, as described above, for example, 50 mol% or less, preferably 45 mol% or less, and more preferably 42 mol% or less. In addition, the degree of acetylation represents the ratio of acetyl groups to all the vinyl monomer units constituting the polyvinyl acetal resin.

The weight average molecular weight (Mw) of the polyvinyl acetal resin is preferably from 50,000 to 800,000. By adjusting the weight average molecular weight within the above-mentioned range, it becomes easy to make the shear storage modulus within the desired range, maintain mechanical strength, flexibility, etc., and improve adhesiveness. From these viewpoints, the weight average molecular weight (Mw) of the polyvinyl acetal resin is more preferably 100,000 or more, more preferably 120,000 or more, still more preferably 150,000 or more. Moreover, the weight average molecular weight (Mw) is more preferably 600,000 or less, still more preferably 500,000 or less, still more preferably 400,000 or less. In addition, weight average molecular weight (Mw) was measured by the gel permeation chromatography.

The aldehyde used for producing the polyvinyl acetal resin is not particularly limited, and is, for example, an aldehyde having 1 to 20 carbon atoms, and generally, an aldehyde having 2 to 10 carbon atoms can be suitably used. The above-mentioned aldehydes having 2 to 10 carbon atoms are not particularly limited, for example, acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, n-pentanal, 2-ethylbutyraldehyde, n-hexanal, n-octylaldehyde , n-nonanal, n-decyl aldehyde, benzaldehyde, etc. Among them, aldehydes having 2 to 6 carbon atoms such as acetaldehyde, n-butyraldehyde, n-hexanal, and n-valeraldehyde are preferable, aldehydes having 2, 3, and 4 carbon atoms are more preferable, and n-butyraldehyde is still more preferable. These aldehydes may be used individually, or may use 2 or more types together. The polyvinyl acetal resin used in the present invention may be used alone or in combination of two or more.

When the adhesive film of the present invention uses polyvinyl acetal resin as the thermoplastic resin, as long as the effect of the present invention is exhibited, it may have a thermoplastic resin other than polyvinyl acetal resin. However, polyvinyl acetal resin is preferably used as the main component. The thermoplastic resin other than polyvinyl acetal resin is as above-mentioned. Specifically, the content of the polyvinyl acetal resin is based on the total amount of thermoplastic resin contained in the adhesive film, for example, at least 50% by mass, preferably at least 70% by mass, more preferably at least 90% by mass, and most preferably at least 90% by mass. 100% by mass. Therefore, the thermoplastic resin contained in the adhesive film of this invention may consist only of polyvinyl acetal resin.

(Plasticizer) The adhesive film of the present invention may also contain a plasticizer. The adhesive film becomes soft by containing a plasticizer, which can lower the maximum peak temperature of tanδ of the adhesive film, and improve the adhesion to various resin materials such as polycarbonate or various substrates such as inorganic glass. However, the adhesive film of the present invention does not contain plasticizer, or contains a small amount of plasticizer. By containing only a small amount of a plasticizer or not containing a plasticizer, it is possible to prevent the plasticizer from seeping out, and to improve the seeping out property. In addition, even if the adhesive film of the present invention contains a small amount of plasticizer or does not contain a plasticizer, the adhesion to resin materials such as polycarbonate can be improved by using the above-mentioned specific thermoplastic resin.

The content of the plasticizer in the adhesive film is less than 20 parts by mass relative to 100 parts by mass of the thermoplastic resin contained in the adhesive film. When the plasticizer is 20 parts by mass or more, disadvantages such as the plasticizer oozes out and contaminates peripheral members occur. From the viewpoint of exudation, the above content of the plasticizer is preferably at most 15 parts by mass, more preferably at most 10 parts by mass, further preferably at most 5 parts by mass, even more preferably at most 1 part by mass. The lower limit of the content of the plasticizer is 0 parts by mass. When the modified polyvinyl acetal resin (A) is used for the resin composition of the present invention, the plasticizer may not be included, but the adhesiveness of the resin film becomes easy to improve by including the plasticizer. On the other hand, when an unmodified polyvinyl acetal resin is used for the resin composition, it is preferable to contain a plasticizer from the viewpoint of improving the adhesiveness of the resin film.

As the plasticizer, for example, organic phosphorus plasticizers such as organic ester plasticizers, organic phosphoric acid ester plasticizers and organic phosphite plasticizers, polyalkylene glycol plasticizers, Organic ether-based plasticizers such as polyoxyalkylene ether-based plasticizers, alcohol-based plasticizers, and the like. A plasticizer may be used individually by 1 type, and may use 2 or more types together. Among the above, organic ester plasticizers and organic ether plasticizers are preferable. As a preferable organic ester plasticizer, a monobasic organic acid ester, a polybasic organic acid ester, etc. are mentioned.

As a monobasic organic acid ester, the ester of a diol and a monobasic organic acid is mentioned. Examples of diols include polyalkylenes in which each alkylene unit has 2 to 4 carbon atoms, preferably 2 or 3 carbon atoms, and the repeating number of alkylene units is 2 to 10, preferably 2 to 4. Alkyl glycols. Moreover, the diol may be a monoalkylene glycol having 2 to 4 carbon atoms, preferably 2 or 3 carbon atoms (that is, the repeating unit is 1). Specifically, the diol may, for example, be ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol or butanediol. Examples of monobasic organic acids include organic acids having 3 to 10 carbon atoms, specifically, butyric acid, isobutyric acid, hexanoic acid, 2-ethylbutyric acid, heptanoic acid, n-octanoic acid, 2 -Ethylhexanoic acid, n-nonanoic acid, capric acid, etc.

Specific monobasic organic acids include: triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethylene glycol dicaprylate, Ethylene glycol di-n-caprylate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, tetraethylene glycol di-2-ethylhexanoate, diethylene glycol di-2 -Ethyl butyrate, diethylene glycol di-2-ethylhexanoate, dipropylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylvalerate, tetraethylene glycol Alcohol di-2-ethylbutyrate, diethylene glycol dicaprylate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, triethylene glycol di-2-ethyl Butyrate, Ethylene Glycol Di-2-Ethyl Butyrate, 1,2-Propanediol Di-2-Ethyl Butyrate, 1,3-Propanediol Di-2-Ethyl Butyrate, 1,4 -Butanediol di-2-ethylbutyrate, 1,2-butanediol di-2-ethylbutyrate, etc.

Moreover, as a polybasic organic acid ester, the ester compound of the dibasic organic acid with 4-12 carbon atoms, such as adipic acid, sebacic acid, and azelaic acid, and the alcohol with 4-10 carbon atoms is mentioned, for example. Alcohols having 4 to 10 carbon atoms may be linear, branched or cyclic. Specifically, dibutyl sebacate, dioctyl azelate, dihexyl adipate, dioctyl adipate, hexyl cyclohexyl adipate, diiso Nonyl, nonyl heptyl adipate, dibutyl carbitol adipate, mixed adipate, etc. Also, oil-modified sebacic acid alkyd and the like may be used. The mixed type adipate may, for example, be an adipate produced from two or more alcohols selected from alkyl alcohols having 4 to 9 carbon atoms and cyclic alcohols having 4 to 9 carbon atoms. Phosphoric acid esters, such as tributoxyethyl phosphate, isodecylphenyl phosphate, and triisopropyl phosphate, etc. are mentioned as said organophosphorus plasticizer.

The organic ester plasticizer is not limited to the complete esters of the above-mentioned esters, and may be partial esters. For example, it may be a partial ester of a diol and a monobasic organic acid, or a partial ester of a dibasic organic acid and an alcohol. Specifically, triethylene glycol-mono-2-ethylhexanoate and the like may, for example, be mentioned. Furthermore, trivalent or higher alcohols such as glycerin, partial esters with monobasic organic acids, and the like may be used. The monobasic organic acid may, for example, be a monobasic organic acid having 3 to 24 carbon atoms, preferably a monobasic organic acid having 6 to 18 carbon atoms. Specific examples of partial esters of tribasic or higher alcohols and monobasic organic acids include mono- or diesters of glycerin and stearic acid, mono- or diesters of glycerin and 2-ethylhexanoic acid, and the like. Among the above-mentioned organic ester plasticizers, triethylene glycol-di-2-ethylhexanoate (3GO) can be used particularly suitably.

Examples of polyalkylene glycol-based plasticizers include polyethylene glycol, polypropylene glycol, poly(ethylene oxide/propylene oxide) block copolymers, poly(ethylene oxide/propylene oxide) Random copolymers, polytetramethylene glycol, and the like, among which polypropylene glycol is preferred.

Polyoxyalkylene ether plasticizers are ether compounds of monohydric or polyhydric alcohols and polyoxyalkylene groups. As specific polyoxyalkylene ether plasticizers, for example, polyoxyethylene hexyl ether, polyoxyethylene heptyl ether, polyoxyethylene octyl ether, polyoxyethylene-2 -Ethylhexyl ether, polyoxyethylenenonyl ether, polyoxyethylenedecyl ether, polyoxyethylene allyl ether, polyoxypropylene allyl ether, polyoxyethylene glyceryl ether, polyoxyethylene Propyl glyceryl ether, polyoxyethylene diglyceryl ether, polyoxypropylene diglyceryl ether, polyoxyalkylene neopentylthritol ether, and the like. The polyoxyalkylene ether-based plasticizer is preferably an ether compound of a polyol and a polyoxyalkylene group, more preferably an ether compound of glycerin or diglycerin and a polyoxyalkylene group, and more preferably glycerin or diglycerol Ether compound with polyoxypropylene. As an alcohol-type plasticizer, various polyhydric alcohols, such as butylene glycol, hexylene glycol, trimethylol propane, neopentyl glycol, are mentioned. Among them, trimethylolpropane is preferred.

The adhesive film may appropriately contain known additives used in combination with thermoplastic resins in addition to the plasticizer. That is, the adhesive film may be formed of a thermoplastic resin such as polyvinyl acetal resin, but may contain a plasticizer blended as necessary or additives other than the plasticizer in addition to the thermoplastic resin. Specific examples of additives other than plasticizers include: ultraviolet absorbers, infrared absorbers, antioxidants, light stabilizers, adhesion regulators, pigments, dyes, fluorescent whitening agents, crystal nucleating agents, etc. . In addition, the resin composition of the present invention may be diluted with a solvent and used in the form of a diluted solution.

Also, the adhesive film preferably does not contain low molecular weight compounds, or contains only a small amount of low molecular weight compounds. By containing only a small amount of low-molecular-weight compounds or not containing low-molecular-weight compounds, bleeding of low-molecular-weight compounds can be prevented and bleeding properties can be improved. Furthermore, a low molecular weight compound refers to a compound having a molecular weight of less than 1000, and examples thereof include the above-mentioned plasticizers, or reactive diluents that harden when irradiated with light. Examples of reactive diluents include: (meth)acrylic reactive diluents such as (meth)acrylic monomers and (meth)acrylic oligomers; epoxy monomers, epoxy oligomers, etc. Epoxy-based reactive diluents such as alkoxysilane monomers, alkoxysilane oligomers, and other polysiloxane-based reactive diluents. The content of the low-molecular-weight compound in the adhesive film is, for example, less than 20 parts by mass relative to 100 parts by mass of the thermoplastic resin contained in the adhesive film from the viewpoint of exudation. The content of the low-molecular-weight compound is preferably at most 15 parts by mass, more preferably at most 10 parts by mass, still more preferably at most 5 parts by mass, and still more preferably at most 1 part by mass, from the viewpoint of further improving the exudation property. . The lower limit of the content of the low molecular weight compound is 0 parts by mass.

[Manufacturing method of polyvinyl acetal resin] The polyvinyl acetal-based resin used in the adhesive film of the present invention is obtained by "using aldehyde to acetalize polyvinyl alcohol (also called "raw material polyvinyl alcohol"), and then reacting with a modifier as necessary. or by reacetylation treatment". As the raw material polyvinyl alcohol, unmodified polyvinyl alcohol may be used, and when a modified polyvinyl acetal resin is obtained, modified polyvinyl alcohol may be used as the raw material polyvinyl alcohol. For example, when manufacturing the modified polyvinyl acetal resin (A) which has a polyalkylene oxide structure, it is preferable to manufacture by the following manufacturing method (1).

(Manufacturing method (1)) In this production method (1), first, polyoxyalkylene-modified polyvinyl alcohol as a raw material polyvinyl alcohol is produced. Specifically, it can be obtained by polymerizing vinyl ester and a monomer including a vinyl monomer having a polyoxyalkylene group to obtain a polymer, and then saponifying the polymer. Generally, an alkali or an acid is used for saponification, but it is preferable to use an alkali. As polyoxyalkylene-modified polyvinyl alcohol, only 1 type may be used, and 2 or more types may be used together. Next, the polyoxyalkylene group-modified polyvinyl alcohol obtained above can be acetalized with aldehyde to obtain a modified polyvinyl acetal resin (A). The method of acetalization can be performed by a well-known method.

Vinyl acetate, vinyl formate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, trimethyl vinyl acetate, neodecanoic acid ( versatic acid) vinyl ester, vinyl caproate, vinyl caprylate, vinyl laurate, vinyl palmitate, vinyl stearate, vinyl oleate, vinyl benzoate, etc. Among them, vinyl acetate is preferred.

Moreover, as a vinylic monomer which has a polyoxyalkylene group used by the manufacturing method (1), the compound represented by following formula (4) is mentioned specifically,. Among them, polyoxyalkylene vinyl ethers represented by the following formula (4-1) and polyoxyalkylene allyl ethers represented by the following formula (4-2) are preferable.

（式（4）中，A ¹O、R ¹、R ²、m係與上述相同）

(In formula (4), A ¹ O, R ¹ , R ² , and m are the same as above)

（式（4-1）、（4-2）中，A ¹O、m、及R ¹分別與上述相同）

(In formulas (4-1) and (4-2), A ¹ O, m, and R ¹ are the same as above, respectively)

Preferred specific examples of vinyl monomers having polyoxyalkylene groups include: polyoxyethylene monovinyl ether, polyoxyethylene polyoxypropylene monovinyl ether, polyoxypropylene Monovinyl ether, polyoxyethylene monoallyl ether, polyoxyethylene polyoxypropylene monoallyl ether, polyoxypropylene monoallyl ether, polyoxyethylene alkyl vinyl ether, polyoxyethylene Oxyethylene polyoxypropylene alkyl vinyl ether, polyoxypropylene alkyl vinyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene polyoxypropylene alkyl allyl ether , polyoxypropylene alkyl allyl ether, etc.

Moreover, in the case of an unmodified polyvinyl acetal resin, it is preferable to manufacture by the following manufacturing method (2). (Manufacturing method (2)) In this production method (2), polyvinyl acetal-based resin (hereinafter, also referred to as raw material polyvinyl acetal-based resin) is obtained by acetalizing raw material polyvinyl alcohol with aldehyde. Here, unmodified polyvinyl alcohol obtained by saponifying polyvinyl ester was used as the raw material polyvinyl alcohol. Next, the raw polyvinyl acetal resin can be reacetylated to obtain an unmodified polyvinyl acetal resin. The reacetylation treatment can be performed by a conventionally known method, but it may be performed in the presence of a base such as pyridine using acetic anhydride. Also, the reacetylation treatment can be carried out by heating, for example, at a temperature of 50°C to 100°C, preferably 70°C to 90°C. For polyvinyl acetal-based resins, by reacetylation treatment, the amount of hydroxyl groups decreases, and the maximum peak temperature of tan δ becomes easy to lower, so that the adhesion to various resin materials such as polycarbonate becomes good.

Moreover, the modified polyvinyl acetal resin which has an alkyl group in a side chain can be manufactured by the following manufacturing methods, for example. First, polyvinyl acetal-based resin (hereinafter, also referred to as raw material polyvinyl acetal-based resin) is obtained by acetalizing raw material polyvinyl alcohol with aldehyde. The raw polyvinyl alcohol used here is obtained by saponifying polyvinyl ester, preferably unmodified polyvinyl alcohol. Next, a modifying agent having an alkyl group is reacted with the above-mentioned raw material polyvinyl acetal resin to introduce an alkyl group into the raw material polyvinyl acetal resin. The modifying agent may be a compound having "a reactive group that reacts with a hydroxyl group of the raw material polyvinyl acetal resin to form an urethane bond or an ester bond." Specifically, an alkyl isocyanate whose alkyl group has 2 to 30 carbon atoms, such as n-octadecyl isocyanate, may be mentioned. Further, examples thereof include carboxylic acids having 3 to 31 carbon atoms, or carboxylic acid derivatives such as anhydrides, carboxylic acid esters, and carboxylic acid halides of the above carboxylic acids. As the carboxylic acid derivative, carboxylic acid chlorides such as 2-ethylhexyl chloride, lauryl chloride, myristyl chloride, palmityl chloride, and stearyl chloride are preferable.

The adhesive film of the present invention not only refers to the adhesive film alone, but also widely includes the case where it is laminated, coated, etc. on other members to form a layered or filmy form. Generally speaking, it is called a sheet with a relatively large thickness. Also known as adhesive membrane. The thickness of the adhesive film is not particularly limited, for example, it is not less than 100 μm and not more than 2000 μm, preferably not less than 100 μm and not more than 1000 μm. Also, regarding the adhesive film, in order to improve the collision safety, the thickness of the adhesive film is preferably as large as possible, more preferably at least 200 μm, further preferably at least 300 μm. Also, from the viewpoint of thinning, the thickness of the adhesive film is preferably 500 μm or less.

The adhesive film of the present invention may be composed of a single layer. The layers constituting the monolayer film may have the composition as described above for the adhesive film. That is, the layer constituting the monolayer film may contain a thermoplastic resin and not contain a plasticizer, or may contain a plasticizer in the above-mentioned content. Furthermore, as mentioned above, additives can also be blended suitably.

In addition, the adhesive film of the present invention may be a multilayer film of two or more layers. The multilayer film may have the composition as described above for the above-mentioned adhesive film, but each layer (hereinafter, also referred to as "first layer") may have the composition as described for the above-mentioned adhesive film. That is, each first layer may contain a thermoplastic resin as described in the above-mentioned adhesive film, and may not contain a plasticizer, or may contain a plasticizer in the above-mentioned content. Furthermore, as mentioned above, additives can also be blended suitably. Details of the thermoplastic resin, plasticizer, and additives in each first layer of the multilayer film, and details of the content of each component are as described in the above-mentioned adhesive film. However, the thermoplastic resin used as a content standard is the thermoplastic resin contained in each first layer. In a multilayer film, each first layer may have the same composition or may have a different composition. In addition, the multilayer film may be a laminate of the above-mentioned first layer and layers other than the first layer (hereinafter also referred to as "second layer"). Specifically, for example, a three-layer structure of first layer/second layer/first layer, etc. may be mentioned. Furthermore, when the adhesive film of the present invention is a multilayer film of two or more layers, each layer preferably has the composition described above for the adhesive film.

[Manufacturing method of adhesive film] The adhesive film of the present invention can be produced by "molding a resin composition containing a thermoplastic resin such as polyvinyl acetal resin into a film shape by a known method". The resin composition can be prepared by including at least a thermoplastic resin such as polyvinyl acetal resin produced in the above-mentioned manner, and adding a plasticizer, an additive, etc. as necessary. In addition, the resin composition can also be used by diluting it in a solvent appropriately.

More specifically, the adhesive film can be formed into a film by applying the resin composition on a support such as a release sheet, or pouring it into a mold frame, heating and drying as necessary, or by Molded into a film shape by extrusion molding, press molding, or the like. Also, as described above, when polyvinyl acetal resin is obtained by reacting the raw material polyvinyl acetal resin with a modifying agent, it can also be molded as follows. That is, a composition containing additives such as raw material polyvinyl acetal resin, a modifier, and other plasticizers blended as needed may be coated on a support such as a release sheet, or poured into a mold frame. , followed by heating, whereby the modifier reacts with the raw material polyvinyl acetal resin and is formed into a film.

Furthermore, when the adhesive film is a multilayer film, a resin composition constituting each layer may be prepared, and each layer of the multilayer film may be obtained from the resin composition constituting each layer. In the case of a multilayer structure, it can be obtained by appropriately stacking each layer, or a multilayer structure can be formed by coextrusion or the like.

The adhesive film of the present invention can be used in various applications without particular limitation, and is preferably used in various display applications, laminated glass applications, and the like. The display is preferably for vehicle use, but is not particularly limited. In addition, laminated glass is used in various vehicles such as automobiles and trams, ships, and aircraft; or in various buildings such as high-rise buildings, apartments, independent houses, halls, and gymnasiums; or in machine tools such as cutting and grinding, excavators, and cranes. Window glass for construction machinery, etc., among them, it is preferably used for vehicles such as automobiles. The adhesive film of the present invention has high collision safety, and even in the event of a collision accident, etc., the laminates described below are less likely to be damaged, so it is suitable for vehicle-mounted displays and vehicle window glasses.

＜Laminates＞ The adhesive film of the present invention is preferably used together with substrates such as organic material substrates and inorganic material substrates as part of a laminate, but is not particularly limited. Specifically, the laminate of the present invention may include: the above-mentioned adhesive film, and at least any one of an inorganic material base material and an organic material base material. In addition, the adhesive film is preferably arranged to be attached to at least any one of the inorganic material substrate and the organic material substrate, and is more preferably arranged at a position adjacent to the organic material substrate. Since the adhesive film has high adhesive force to various resin materials, it can be adhered to the substrate with high adhesive force by being arranged at a position to be bonded to the organic material substrate.

As an organic material base material, an organic resin board, a resin film, etc. are mentioned. Organic resin board is also called plexiglass board. The organic resin board is not particularly limited, and examples thereof include (meth)acrylic boards such as polycarbonate boards and polymethyl methacrylate boards, acrylonitrile-styrene copolymer boards, acrylonitrile-butadiene-styrene copolymer boards, and acrylonitrile-butadiene-styrene copolymer boards. Polyester boards such as polyethylene terephthalate boards, fluorine resin boards, polyvinyl chloride boards, chlorinated polyvinyl chloride boards, polypropylene boards, polystyrene boards, polystyrene boards, epoxy resins Various plexiglass plates such as phenolic resin plate, unsaturated polyester resin plate, polyimide resin plate, etc. The organic resin board can also be properly surface-treated. Among the above, polycarbonate sheets are preferred in terms of excellent transparency and impact resistance, and (meth)acrylic sheets are preferred in terms of high transparency, excellent weather resistance, and mechanical strength. Plate, wherein, more preferably polycarbonate plate. The thickness of the organic resin plate is not particularly limited, but is preferably at least 0.1 mm, more preferably at least 0.4 mm, and is preferably at most 5.0 mm, and still more preferably at most 3.0 mm.

The resin film is not particularly limited, and examples thereof include polyester films such as (meth)acrylic resin films, polycarbonate films, polyethylene terephthalate (PET) films, and polyethylene naphthalate (PEN) films. Polyolefin resin film such as ester resin film, polyethylene film, polypropylene film, cyclic polyolefin (COP) film, triacetyl cellulose (TAC) film, polyether sulfide (PES) resin film, polyimide resin film etc. In addition, a surface layer composed of a hard coat layer "composed of (meth)acrylic resin or the like" may be provided on the surface of the resin film. The thickness of the resin film is not particularly limited, but is preferably at least 30 μm, more preferably at least 50 μm, and is preferably at most 500 μm, further preferably at most 450 μm. Furthermore, those with relatively large thickness and low flexibility that cannot be bent are generally called organic resin sheets. On the other hand, those with relatively small thickness and generally can be bent are roughly called resin films. be clearly distinguished.

As the inorganic material substrate, an inorganic glass plate may, for example, be mentioned. The inorganic glass plate is not particularly limited, and examples thereof include float plate glass, tempered glass, colored glass, polished plate glass, patterned glass, laminated plate glass, laminated plate glass, ultraviolet absorbing plate glass, and infrared reflecting plate Various glass plates such as glass, infrared absorbing plate glass, and green glass. Inorganic glass can also be surface treated. The thickness of the inorganic glass is not particularly limited, but is preferably 0.1 mm or more, more preferably 1.0 mm or more, and is preferably 5.0 mm or less, and further preferably 3.0 mm or less.

The organic material substrate or the inorganic material substrate can also be properly attached with electrodes, sensors, and the like. The electrodes are composed of conductive layers laminated on the above-mentioned substrates. The sensor may, for example, be a touch sensor. The touch sensor is a sensor that senses the touch input of a finger, stylus, or other objects approaching or touching the substrate, and is composed of a conductive layer laminated on the above substrate. The touch sensor will generate electrical changes such as electrostatic capacitance, current, and voltage on the conductive layer when fingers, stylus, and other objects approach or touch the substrate, and sense touch input according to the electrical changes. The conductive layer is not particularly limited, as long as it is a previously known transparent electrode material, it can be used without particular limitation, for example: indium tin oxide (ITO) conductive film, tin oxide conductive film, zinc oxide conductive film, etc. film, polymer conductive film, etc.

Among the above, the inorganic material substrate is preferably selected from the group consisting of an inorganic glass plate and an inorganic glass plate with at least any one of electrodes or sensors attached thereto. The organic material substrate is preferably selected from polycarbonate plates, (meth) acrylic plates, and PET films, COP films, polycarbonate films, and at least any one of electrodes or sensors attached to these films. At least one of the group consisting of membranes of the dead. In addition, the above-mentioned hard coat layer can also be formed on the opposite side of the surface of the organic material substrate (especially film) on which the conductive layer such as electrodes and sensors is laminated. The surface opposite to the surface on which the conductive layer is provided is usually an adhesive surface to the adhesive film, but the adhesive film of the present invention can also have high adhesion to the surface on which the hard coat layer is provided.

The laminate is not particularly limited, but preferably includes a pair of substrates selected from inorganic material substrates and organic material substrates, and an adhesive film disposed between the pair of substrates, and has three or more layers. The multi-layer structure. In such a multilayer structure, the adhesive film can be attached to both of a pair of base materials, for example, so that the pair of base materials can be bonded through the adhesive film. In this case, the adhesive film of the present invention described above may be used as the adhesive film for the adhesive film.

In addition, the laminate may have a structure in which another intermediate member is disposed between the above-mentioned pair of base materials. In such a structure, an adhesive film may be disposed between each base material and the intermediate member, and it may have a multilayer structure of five or more layers. structure. Here, the adhesive film can be attached to each base material and the intermediate member, whereby the base material and the intermediate member can be bonded through the adhesive film. Also, in the multilayer structure of more than 5 layers described above, the adhesive film between the base material and the intermediate member is a resin film, as long as at least one of them is the adhesive film of the present invention, but it is preferred that both are based. Adhesive film invented. The intermediate member may have at least any one of the above-mentioned inorganic material substrate and organic material substrate, and at least one of the inorganic material substrate and the organic material substrate may be disposed at a position where the adhesive film of the present invention is adhered.

The laminated body demonstrated above should just comprise a display, laminated glass, etc., but is not limited to these. In addition, as described below, the intermediate member may be a touch panel, a light control element, etc., but is not limited thereto. In addition, the above-mentioned inorganic material base material or organic material base material only needs to constitute a part of a touch panel, a dimming element, a display element constituting a display, and the like.

The laminate of the present invention can be produced, for example, by preparing an adhesive film and press-bonding each member through the prepared adhesive film. For example, it can manufacture by laminating|stacking a base material, an adhesive film, and a base material sequentially, and crimping them. In addition, when an intermediate member is provided, it can be produced by laminating the base material, the adhesive film, the intermediate member, the adhesive film, and the base material in order, and bonding them together by pressure.

Next, specific examples of the laminate will be described with reference to the drawings. Fig. 1 shows a laminated body according to the first embodiment. In 1st Embodiment, 30 A of laminated bodies are applied to the display with a touch panel. The display with a touch panel is preferably a display for vehicles. The laminate 30A of this embodiment includes a display element 31 , a surface protection panel 32 , and a touch panel 33 arranged between the display element 31 and the surface protection panel 32 , and between the touch panel 33 and the display element 31 , and Adhesive films 34A and 34B are arranged between the surface protection panel 32 and the touch panel 33 , respectively.

The surface protection panel 32 is preferably either an organic resin plate or an inorganic glass plate, but is preferably an inorganic glass plate. Moreover, as the display element 31, an organic EL display element and a liquid crystal display element are mentioned, for example. The display element 31 is preferably provided with a polarizing plate on the outermost surface of the display element 31 . In addition, the outermost on the surface side means the outermost on the surface protection panel side, and the opposite side is also called the back side. A polarizing plate generally has a configuration in which protective films are provided on both surfaces of a polarizing element such as a polyvinyl alcohol resin film. The protective film is composed of the above-mentioned resin film, preferably any one of PET film, COP film, or TAC film. Therefore, an organic material substrate is generally disposed on the outermost surface of the display element 31 . Also, even when the display element 31 is not provided with a polarizing plate on its surface side, a protective film may be provided on the outermost surface of the surface side. Therefore, in this case, the outermost surface of the surface side of the display element 31 It is also composed of organic material substrates.

The touch panel 33 may be made of inorganic glass with a touch sensor, an organic resin board, or a resin film, but is preferably an inorganic glass with a touch sensor or a resin film. Moreover, in the touch panel 33, two or more of inorganic glass, an organic resin board, or a resin film may be laminated|stacked and it may become a multilayer structure. In this case, in the touch panel 33 , a touch sensor may be attached to any one of inorganic glass, an organic resin plate, or a resin film. Moreover, the touch panel 33 may arrange the protective film which consists of a resin film on either surface of the outermost surface of a front side, and the outermost surface of a back side. Therefore, the bonding surfaces of the touch panel 33 and the bonding films 34A and 34B are any of inorganic glass, organic glass, and resin film.

Next, the films 34A and 34B are respectively attached to the display element 31 and the touch panel 33 , and the touch panel 33 and the surface protection panel 32 to join them together. Any one of the subsequent films 34A and 34B may be the above-mentioned adhesive film of the present invention, preferably both are the adhesive film of the present invention. The adhesive film of the present invention not only has high adhesion to inorganic material substrates, but also has high adhesion to various resin materials (ie, organic material substrates). Therefore, the adhesive surfaces of the display element 33, the surface protection panel 32, and the touch panel 33 and the adhesive films 34A, 34B may be made of an organic material base material, but even in this case, it is possible to achieve a high adhesive strength. The display element 31 and the touch panel 33 , and the surface protection panel 32 and the touch panel 33 are bonded. In addition, since the adhesive film of the present invention has high collision safety, even when the display with a touch panel is a vehicle-mounted display, it can prevent serious damage caused by damage to the display with a touch panel. Furthermore, since bleeding property is good, contamination of the touch panel 33, the display element 31, etc. by bleeding can be prevented.

Fig. 2 shows a laminated body of a second embodiment. The laminated body of the second embodiment is also applied to a display, but the laminated body 30B omits the touch panel 33, so the laminated body 30B includes a display element 31, a surface protection panel 32, and an adhesive film 34 arranged therebetween. Details of the display element 31 and the surface protection panel 32 are as described in the first embodiment. In the present embodiment, the adhesive film 34 is composed of the adhesive film of the present invention. The next film 34 (adhesive film) is bonded to the display element 31 and the surface protection panel 32 to bond them. Therefore, the display element 31 and the surface protection panel 32 are bonded with high adhesive force similarly to the first embodiment. In addition, since the adhesive film has high collision safety and high bleedability, even if the laminate 30B is applied to a vehicle-mounted display, it is difficult to cause serious damage due to damage to the display, and it is also possible to prevent contamination of the display element 31, etc. .

Furthermore, in the second embodiment, the surface protection panel 32 may also be an OGS (one glass solution, monolithic glass solution) panel, and sensors such as touch sensors may also be disposed on the surface protection panel 32 . Therefore, the surface protection panel 32 may also be made of inorganic glass with a sensor or the like.

Fig. 3 shows a laminated body of a third embodiment. The laminated body 30C of the third embodiment is applied to laminated glass with a dimming function. The laminated body 30C of this embodiment includes: a pair of laminated glass members (substrates) 41, 42, and a dimming element 43 arranged between the pair of laminated glass members 41, 42. Adhesive films 34A and 34B are disposed between the light-adjusting elements 43 and between the other laminated glass member 42 and the light-adjusting elements 43 , respectively. The laminated glass members 41 and 42 may be either inorganic glass plates or organic resin plates, and the details thereof are as described above.

The dimming element 43 is preferably a dimming film including two resin films and a dimming layer arranged between the two resin films. Therefore, the bonding surfaces of the light-adjusting element 43 and the bonding films 34A and 34B are made of a resin material. The resin film included in the dimming element 43 may, for example, be a polyester resin film such as a PET film or a PEN film, a (meth)acrylic resin film, a TAC film, a PES resin film, or a polyimide resin film. Among them, a polyester resin film is preferable from the viewpoint of handleability and the like, and among them, a PET film is more preferable. In addition, two resin films are respectively provided with a conductive layer constituting an electrode on the surface on the side of the light-adjusting layer.

The light-adjusting layer changes the transmittance of visible light by switching between the voltage applied and the non-applied voltage between the conductive layers of the two resin films. The dimming layer can be composed of a liquid crystal layer such as polymer dispersed liquid crystal (PDLC). In addition, the dimming film may also be an SPD (Suspended Particle Device, suspended particle device) film, an electrochromic film, an electrophoretic film device, and the like. Therefore, the light-adjusting layer can be an SPD layer comprising a resin matrix and a light-adjusting suspension dispersed in the resin matrix, or an electrochromic material layer. Also, an electrophoretic layer including electrophoretic particles and a dispersant for dispersing the electrophoretic particles may be used.

In the present embodiment, the bonding films 34A and 34B are respectively bonded to the laminated glass member 41 and the dimming element 43 , and the laminated glass member 42 and the dimming element 43 . The subsequent films 34A and 34B are resin films, either of which may be the above-mentioned adhesive film of the present invention, but preferably both are the adhesive film of the present invention. The adhesive film of the present invention not only has high adhesion to inorganic material substrates, but also has high adhesion to various resin materials, so the laminated glass members 41, 42 and light-adjusting element 43 can be bonded with high adhesion. In addition, since the adhesive film of the present invention has high collision safety, even when the laminated glass of the third embodiment is used for a window glass for a vehicle, it can prevent great damage due to breakage. Furthermore, since the bleedout property is good, it is also possible to prevent contamination of the light adjustment element 43 and the like due to bleedout.

Fig. 4 shows a laminated body according to a fourth embodiment. The laminated body 30D of this embodiment is applied to laminated glass. The laminate 30D of this embodiment includes a pair of laminated glass members 41, 42, and an adhesive film 34 arranged between the pair of laminated glass members 41, 42. The adhesive film 34 can be made of the above-mentioned adhesive film of the present invention. constitute. The pair of laminated glass members 41 and 42 are as described in the third embodiment. Since the subsequent film 34 (adhesive film) is bonded to both the laminated glass members 41 and 42 to bond them, the laminated glass members 41 and 42 can be bonded with high adhesive force. In addition, since the adhesive film has high collision safety and high exudability, even if the laminated glass is used for a vehicle window glass, it is not easy to cause great damage due to damage to the vehicle window glass, and it can also prevent the surrounding area from being damaged. Contamination of components, etc.

In addition, in the above-mentioned first to fourth embodiments, an example in which the adhesive film is a single-layer adhesive film has been assumed and described, but a multilayer film may also be used as the adhesive film. The constitution of the multilayer film is as described above. [Example]

The present invention will be described in further detail by way of examples, but the present invention is not limited by these examples. In addition, the measuring method and evaluation method of each physical property value of this invention are as follows.

＜Weight average molecular weight (Mw)＞ The adhesive film was dissolved in tetrahydrofuran to a concentration of 0.05% by weight, filtered using a syringe filter (manufactured by Merck, Millex-LH 0.45 μm), and the molecular weight was measured by gel permeation chromatography (manufactured by Waters, e2690) . The weight average molecular weight (Mw) was calculated using the molecular weight calibration curve prepared from the monodisperse polystyrene standard sample. In addition, Shodex GPC KF-806L (manufactured by Showa Denko Co., Ltd.) was used for the column, and tetrahydrofuran was used for the eluent.

<Shear storage modulus, and maximum peak temperature of tanδ> The adhesive films obtained in Examples and Comparative Examples were cut into pieces with a length of 10 mm and a width of 5 mm, using a dynamic viscoelasticity measuring device (manufactured by IT Measurement Control Co., Ltd., trade name "DVA-200"), and measured in the following Measure the viscoelasticity under the conditions, and check the shear storage modulus (G') at 20°C. Also, the peak temperature of the loss tangent tan δ obtained from the result of the viscoelasticity measurement was read. In the temperature range of -50 to 150°C, the peak temperature at which tan δ reaches the maximum among the above peak temperatures was taken as the maximum peak temperature of tan δ. (measurement conditions) Deformation method: shear mode, measurement temperature: -50℃～200℃, heating rate: 5℃/min, measurement frequency: 1 Hz, strain: 1%

＜Amount of modification, degree of acetalization, degree of acetylation, and amount of hydroxyl groups＞ Polyvinyl acetal-based resin was dissolved in chloroform-d, measured using 1H-NMR (nuclear magnetic resonance spectrum), and the molar ratio of each unit was analyzed to obtain it.

＜Adhesion to polycarbonate substrate (PC)＞ Adhesion to polycarbonate substrates was measured using the adhesive films of Examples and Comparative Examples according to the method described in the specification, and evaluated based on the following criteria. (evaluation criteria) AA: The maximum load is 200 N or more. A: The maximum load is more than 100 N but less than 200 N. B: The maximum load is less than 100 N.

＜Collision Safety＞ Prepare 2 pieces of float glass with a square size of 30.3 cm and a thickness of 1.1 mm, and overlap the two pieces of float glass with an adhesive film with a square size of 30.3 cm. Thereafter, using a spacer having the same thickness as the stacked structure, the thickness of the adhesive film was fixed, and temporary pressure bonding was carried out in a vacuum laminating machine at 90°C and 0.1 MPa for 3 minutes. Then, the main pressure bonding was further performed for 1 hour under conditions of 90° C. and 0.5 MPa to obtain a laminate. The obtained laminate was fixed with a support frame, and an iron ball with a diameter of 82 mm and a weight of 2.26 kg was dropped from a height of 1.0 m, and the sinking amount of the structure was measured using a high-speed camera. The crash safety was evaluated based on the measured sinking amount. AA: The amount of sinking is 50 mm or less. A: The amount of sinking exceeds 50 mm and is 100 mm or less. B: The amount of sinking exceeds 100 mm.

＜Exudation＞ Using red oil-based marking ink, draw two lines in each of the vertical direction and the horizontal direction on the adhesive films of the examples and the comparative examples for marking. The marked film was arranged so that the main surface was located in a plane parallel to the vertical direction, and it was left to stand at 10° C. for 2 months. After 2 months, visually check whether the marks are blurred or drooped due to substances exuded from plasticizers or the like. The case where none of the 4 marked lines are blurred and sagging, and no bleeding occurs is rated as "AA", and the situation where any of the 4 marked lines is visible, blurring and drooping, but bleeding occurs is rated as "B ".

＜Adhesion to TAC polarizer＞ An adhesive film with dimensions of 10 mm in length and 10 mm in width, a TAC polarizer film made by Sumitomo Chemical Co., Ltd. of 25 mm in length and 100 mm in width, and a float glass of 25 mm in length and 100 mm in width were prepared. TAC polarizer film is made of TAC film on both sides of PVA film. As shown in FIG. 6 , the polarizing plate film 50 made of TAC and the float glass 51 are arranged so that their longitudinal directions are parallel to each other, and are stacked with an adhesive film 52 interposed therebetween. Thereafter, the thickness of the adhesive film 52 was fixed, and temporary pressure bonding was carried out in a vacuum laminating machine at 90° C. and 0.1 MPa for 3 minutes using a spacer having the same thickness as the adhesive film 52 . Then, the main pressure bonding was further performed for 1 hour under the conditions of 90° C. and 0.5 MPa to obtain a laminate 53 . A shear adhesion test was performed on the obtained laminate 53 . Specifically, in an environment at a temperature of 23° C., the polarizer film 50 was stretched at a speed of 200 mm/min in the shear direction S along the longitudinal direction of the float glass 51, and the peeling of the polarizer film was measured. The maximum load (N) at 50 was used as the adhesive force, and the following evaluation criteria were used for evaluation. AA: The maximum load is 220 N or more. A: The maximum load is more than 150 N and less than 220 N. B: The maximum load is less than 150 N.

＜Adhesion to ITO-PET＞ In addition to using a polyethylene terephthalate film (ITO-PET, manufactured by SEKISUI NANO COAT TECHNOLOGY Co., Ltd.) coated with ITO on one side and hard-coated on the opposite side instead of the polarizer film made by TAC, It implemented and evaluated in the same manner as the adhesive force to a TAC polarizing plate. In addition, the hard-coated surface on the opposite side to the surface coated with ITO was set as the surface on which the adhesive film was attached.

(Example 1) [Synthesis of ethylene oxide-modified polyvinyl alcohol] The allyl ether monomer (1) described in Table 1 was prepared. Allyl ether monomer (1) is a compound represented by formula (4-2). A ¹ O is mixed with oxyethylene (EO) and oxypropylidene (PO), and they have a random structure. The molar ratio, the average repeat number of EO and PO, and the terminal group (R ¹ ) are shown in Table 1. Add 515 parts by mass of vinyl acetate, 151 parts by mass of allyl ether monomer (1), and 333 parts by mass of methanol to a flask with a stirrer, a thermometer, a dropping funnel, and a reflux condenser, and replace the nitrogen in the system with The temperature was raised to 60°C. 1.3 parts by mass of 2,2-azobisisobutyronitrile was added to the system while maintaining the temperature at 60° C., and polymerization was started. The polymerization was terminated 5 hours after the initiation of the polymerization. After heating in an oven to remove unreacted monomers and methanol, a 40% by mass methanol solution of the copolymer was prepared. 100 parts by mass of the methanol solution of the obtained copolymer was stirred at 40° C., and 7.4 parts by mass of a 3 mass % NaOH methanol solution was added, fully mixed, and left to stand. After 2 hours, the solidified polymer was pulverized with a pulverizer, washed with methanol, and dried to obtain a polymer powder (ethylene oxide-modified polyvinyl alcohol).

[Preparation of polyvinyl butyral (PVB1)] 280 g of the obtained polymer powder was added to 2100 g of pure water, stirred and dissolved at a temperature of 90° C. for about 2 hours. The solution was cooled to 40°C, 160 parts by mass of hydrochloric acid with a concentration of 35% by mass and 150 parts by mass of n-butyraldehyde were added, the liquid temperature was lowered to 20°C, the temperature was maintained, and the acetalization reaction was carried out to precipitate the reaction product. Thereafter, the liquid temperature was set to 40° C. and held for 3 hours to complete the reaction, neutralized, washed with water, and dried by conventional methods to obtain a white powder of polyvinyl acetal resin (PVB1).

[Production of Adhesive Film] The obtained polyvinyl acetal resin (PVB1) was press-molded at a temperature of 160° C. and a pressure of 20 MPa to obtain an adhesive film with a thickness of 380 μm. For the obtained adhesive film, the maximum peak temperature of tanδ, the shear storage modulus (G'), and the adhesive force to the polycarbonate substrate were measured, and the impact safety, bleeding, and TAC polarizing plate were evaluated. The sticking force.

(Example 2, 3) Except that the thickness of the adhesive film was adjusted as shown in Table 4, it was carried out in the same manner as in Example 1.

(Example 4) The allyl ether monomer used was changed to allyl ether monomer (2), and changed to 723 parts by mass of vinyl acetate, 257 parts by mass of allyl ether monomer (2), and 20 parts by mass of methanol Parts by mass, 1 part by mass of 2,2-azobisisobutyronitrile. Furthermore, after adding the allyl ether monomer (2) and methanol, the temperature in the system was raised to 62°C, and 2,2-azobisisobutyronitrile was added at 62°C to perform polymerization. The same manner as in Example 1 was carried out to obtain PVB2, and an adhesive film was produced in the same manner as in Example 1 using PVB2. The physical properties of the obtained adhesive film were measured or evaluated in the same manner as in Example 1. Furthermore, the allyl ether monomer (2) is a compound represented by formula (4-2), A ¹ O is oxypropylene (PO), and its average repetition number and terminal group (R ¹ ) are shown in Table 1 shown in .

(Example 5) A resin composition was obtained by mixing 15 parts by mass of a plasticizer (triethylene glycol-di-2-ethylhexanoate: 3GO) with respect to 100 parts by mass of PVB2. Using the obtained resin composition, the The pressure molding was performed in the same manner as in Example 1 to produce an adhesive film. The physical properties of the obtained adhesive film were measured or evaluated in the same manner as in Example 1.

(Example 6) Except changing to 552 parts by mass of vinyl acetate, 162 parts by mass of allyl ether monomer (1), 286 parts by mass of methanol, and 1.4 parts by mass of 2,2-azobisisobutyronitrile, the same method as in Example 1 Way implementation, and obtain PVB3, use PVB3, make adhesive film in the same manner as Example 1. The physical properties of the obtained adhesive film were measured or evaluated in the same manner as in Example 1.

(Example 7) Prepare PVB3 obtained by the same method as in Example 6, and mix 10 parts by mass of a plasticizer (3GO) with respect to 100 parts by mass of PVB3 to obtain a resin composition. Using the obtained resin composition, use and Example 1. Press molding in the same way to obtain an adhesive film. The physical properties of the obtained adhesive film were measured or evaluated in the same manner as in Example 1.

(Example 8) Except changing to 572 parts by mass of vinyl acetate, 143 parts by mass of allyl ether monomer (1), 286 parts by mass of methanol, and 0.7 parts by mass of 2,2-azobisisobutyronitrile, the same method as in Example 1 Way implementation, and obtain PVB4, use PVB4, make adhesive film in the same manner as Example 1. The obtained adhesive film was evaluated in the same manner as in Example 1.

(Example 9) Except that the allyl ether monomer used was changed to allyl ether monomer (3), and changed to 751 parts by mass of vinyl acetate, 230 parts by mass of allyl ether monomer (3), and methanol Except 20 parts by mass and 1 part by mass of 2,2-azobisisobutyronitrile, PVB5 was obtained in the same manner as in Example 1, and an adhesive film was produced in the same manner as in Example 1 using PVB5. The obtained adhesive film was evaluated in the same manner as in Example 1. Furthermore, the allyl ether monomer (3) is a compound represented by the formula (4-2), A ¹ O is mixed with oxyethylene (EO) and oxypropylene (PO), the average repetition number, and The terminal groups (R ¹ ) are shown in Table 1.

(Example 10) The allyl ether monomer used was changed to allyl ether monomer (4), and changed to 834 parts by mass of vinyl acetate, 147 parts by mass of allyl ether monomer (4), and 20 parts by mass of methanol parts by mass, 0.5 parts by mass of 2,2-azobisisobutyronitrile. Furthermore, after adding the allyl ether monomer (4) and methanol, the temperature in the system was raised to 52°C, and 2,2-azobisisobutyronitrile was added at 52°C to perform polymerization. Implement in the same manner as in Example 1 to obtain PVB6, and use PVB6 to make an adhesive film in the same manner as in Example 1. The obtained adhesive film was evaluated in the same manner as in Example 1. Furthermore, the allyl ether monomer (4) is a compound represented by formula (4-2), A ¹ O is oxyethylene (EO), and its average repetition number and terminal group (R ¹ ) are shown in Table 1 shown.

(comparative example 1) Using PVB7 which is unmodified polyvinyl butyral as a polyvinyl acetal resin to be used, and mixing 40 parts by mass of a plasticizer (3GO) with respect to 100 parts by mass of PVB7 to obtain a resin composition, Using the obtained resin composition, it press-molded by the same method as Example 1, and obtained the adhesive film. The obtained adhesive film was evaluated in the same manner as in Example 1.

(comparative example 2) Using PVB8 which is unmodified polyvinyl butyral as a polyvinyl acetal resin to be used, and mixing 25 parts by mass of a plasticizer (3GO) with respect to 100 parts by mass of PVB8 to obtain a resin composition, Using the obtained resin composition, it press-molded by the same method as Example 1, and obtained the adhesive film. The obtained adhesive film was evaluated in the same manner as in Example 1.

(Comparative Example 3) As the polyvinyl acetal-based resin to be used, PVB7, which is unmodified polyvinyl butyral, was used. With respect to 100 parts by mass of PVB7, mix 30 parts by mass of a plasticizer (3GO), 10 parts by mass of a reactive diluent (trimethylolpropane triacrylate: TMPA), and a second photopolymerization initiator A resin composition was obtained by using 0.1 parts by mass of phenyl ketone (BP). Using the obtained resin composition, pressure molding was performed in the same manner as in Example 1 to obtain an adhesive film. The exudation property of the obtained adhesive film was evaluated. Also, for the adhesive film, use an ultra-high pressure mercury lamp to irradiate light with a wavelength of 4000 mJ/cm ² at 365 nm, and measure the shear storage modulus (G') and the maximum peak temperature of tanδ after light irradiation. Furthermore, in the evaluation of the adhesive force to the polycarbonate substrate, the impact safety, and the adhesive force to the TAC polarizing plate, the adhesive film prepared in Comparative Example 3 was used to manufacture the laminated film as described in the above-mentioned evaluation methods. The laminated body was irradiated with light of 365 nm wavelength at 4000 mJ/cm ² using an ultra-high pressure mercury lamp. Thereafter, the adhesive force to the polycarbonate substrate, the impact safety, and the adhesive force to the TAC polarizing plate were evaluated.

(Comparative Example 4) PVB8, which is unmodified polyvinyl butyral, was used instead of PVB1 as polyvinyl butyral used as a raw material. With respect to 100 parts by mass of PVB8, 10 parts by mass of plasticizer (3GO), 20 parts by mass of reactive diluent (TMPA), and 0.2 parts by mass of benzophenone as a photopolymerization initiator were mixed to obtain Resin composition: Using the obtained resin composition, it press-molded by the same method as Example 1, and obtained the adhesive film. The exudation property of the obtained adhesive film was evaluated. Also, for the adhesive film, use an ultra-high pressure mercury lamp to irradiate light with a wavelength of 4000 mJ/cm ² at 365 nm, and measure the shear storage modulus (G') and the maximum peak temperature of tanδ after light irradiation. Furthermore, in the evaluation of the adhesive force to the polycarbonate substrate, the impact safety, and the adhesive force to the TAC polarizing plate, the adhesive film prepared in Comparative Example 3 was used to manufacture the laminated film as described in the above-mentioned evaluation methods. The laminated body was irradiated with light of 365 nm wavelength at 4000 mJ/cm ² using an ultra-high pressure mercury lamp. Thereafter, the adhesive force to the polycarbonate substrate, the impact safety, and the adhesive force to the TAC polarizing plate were evaluated.

(comparative example 5) 100 parts by mass of the (meth)acrylic polymer (Ac1) obtained by polymerizing the monomers at the monomer ratios shown in Table 3 was diluted with ethyl acetate so that the solid content would be 45% by mass. On the basis of solid content, 1 part by mass of an isocyanate-based crosslinking agent ("Coronate L-45" manufactured by Nippon Polyurethane Co., Ltd., solid content: 45% by mass) was added to obtain a resin composition. The obtained resin composition was coated on the release-treated surface of the release PET film so that the thickness after drying was 150 μm, and dried at 80° C. for 15 minutes to obtain an adhesive film. The obtained adhesive film was aged at 23° C. for 5 days, and evaluated in the same manner as in Example 1.

(comparative example 6) Except having changed (meth)acryl-type polymer (Ac1) into (meth)acryl-type polymer (Ac2), it implemented similarly to the comparative example 5.

Allyl ether monomers (1) to (4) used as raw materials in Examples are shown in Table 1 below. [Table 1] Allyl ether monomer (1) (2) (3) (4) molecular weight 2500 1500 2000 1500 structure Type of A ¹ O EO - EO EO PO PO PO - PO/EO (mol) 50/50 100/0 50/50 0/100 terminal (R ¹ ) Butyl A hydrogen atom A hydrogen atom A hydrogen atom mean number of repeat units EO twenty three - 19 33 PO twenty three 25 19 -

The PVB1-PVB8 used in the Example and the comparative example are shown in Table 2 below. [Table 2] PVB1 PVB2 PVB3 PVB4 PVB5 PVB6 PVB7 PVB8 Polyvinyl acetal resin Acetyl Content rate (mol%) 1.8 0.9 2.1 1.8 1.2 3.1 1 1 hydroxyl Content rate (mol%) 20.4 27.1 12.4 21.8 18.8 14.5 32 31 Acetal Content rate (mol%) 74.8 70.1 84 73.7 74.7 80.5 67 68 type Butyral Butyral Butyral Butyral Butyral Butyral Butyral Butyral Alkylene oxide structure Content rate (mol%) 3.0 1.9 1.5 2.7 5.3 1.9 - - type EO/PO PO EO/PO EO/PO EO/PO EO - - terminal (R ¹ ) Butyl A hydrogen atom Butyl Butyl A hydrogen atom A hydrogen atom - - Average number of repeating units (EO) twenty three - twenty three twenty three 19 33 - - Average number of repeat units (PO) twenty three 25 twenty three twenty three 19 - - -

The (meth)acrylic polymer used in the comparative example is shown in Table 3 below.

[table 3] Ac1 Ac2 (meth)acrylic polymer Monomer (mass%) n-butyl acrylate 65 25 Methyl methacrylate 26 - ethyl acrylate 4 - Hydroxyethyl Acrylate 1 - 2-Ethylhexyl Acrylate - 32 Isobutyl Acrylate - 27 4-Hydroxybutyl Acrylate - 15 acrylic acid 4 1

Table 4 shows the implementation conditions, physical properties and evaluation results of each Example and Comparative Example. [Table 4] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative Example 5 Comparative Example 6 resin type PVB1 PVB1 PVB1 PVB2 PVB2 PVB3 PVB3 PVB4 PVB5 PVB6 PVB7 PVB8 PVB7 PVB8 Ac1 Ac2 Molecular weight Mw (×10^4) twenty three twenty three twenty three 17 17 35 35 30 twenty two 26 36 19 36 19 65 70 Plasticizer 3GO (parts by mass*1) - - - - 15 - 10 - - - 40 25 30 10 - - reactive diluent TMPA (parts by mass*1) - - - - - - - - - - - - 10 20 - - Photopolymerization initiator BP (parts by mass*2) - - - - - - - - - - - - 1 1 - - crosslinking agent Coronate L-45 (parts by mass*1) - - - - - - - - - - - - - - 1 1 thickness μm 380 150 800 380 380 380 380 380 380 380 150 200 200 200 150 150 tanδmaximum peak temperature temperature (°C) 33.2 33.2 33.2 38.2 23.6 30.1 13.2 41.2 24.1 49.2 26 31 38 After light exposure 46 After light exposure 5 -3 G'@20℃ (10 ⁷ Pa) 3.4 3.4 3.4 4.0 1.4 1.2 0.6 5.3 1.4 5.9 1.5 3.5 4.6 After light exposure 4.0 After light exposure 0.02 0.006 Adhesion to PC Adhesion force (N) 221 210 242 354 332 213 208 156 208 111 twenty three twenty one twenty two 25 260 210 evaluate AAA AAA AAA AAA AAA AAA AAA A AAA A B B B B AAA AAA crash safety AAA A AAA AAA A A A AAA A AAA A AAA AAA AAA B B exudative AAA AAA AAA AAA AAA AAA AAA AAA AAA AAA B B B Before light exposure B Before light exposure AAA AAA For the adhesion of TAC polarizer AAA AAA AAA AAA AAA AAA AAA A AAA A B B B B AAA AAA For the adhesion of ITO-PET AAA AAA AAA AAA AAA AAA AAA A AAA A B B B B AAA AAA *1 Indicates parts by mass relative to 100 parts by mass of thermoplastic resin. ※2 Indicates parts by mass relative to 100 parts by mass of reactive diluent.

The adhesive films of the above embodiments have a higher shear storage modulus at 20°C by using specific thermoplastic resins, and have higher adhesion to polycarbonate substrates, so they have higher collision safety. Moreover, it has high adhesion to various resin materials, and is also excellent in adhesion to TAC polarizing plates. Moreover, since no plasticizer is blended, or only a small amount of plasticizer is blended, the exudation property is also good. On the other hand, in Comparative Examples 1 to 4, since the adhesive force to the polycarbonate base material was low, the adhesive force to various resin materials was insufficient, and the adhesive force to the TAC polarizing plate was also low. Moreover, since a large amount of a plasticizer is blended, or a large amount of a plasticizer and a reactive diluent are blended, the exudation property is also insufficient. In addition, in Comparative Examples 5 and 6, since the shear storage modulus (G') at 20° C. was low, the collision safety was not sufficient.

10:Laminated glass samples 11: Box 13: The side of the box 11 14: notch 16: Base part 17: Press piece 20: Press member 21: Polycarbonate plate glass 22: Polycarbonate sheet L: the distance between the pressing pieces 17 and 17 T: the thickness of the pressing piece 17 W: the width of the pressing piece 17 X: The direction perpendicular to the bonding surface 30A, 30B, 30C, 30D: laminated body 31: Display components 32: Surface protection panel 33: Touch panel 34, 34A, 34B: Adhesive film (adhesive film) 41,42:Laminated glass components 43: Dimming element 50: Polarizing film made by TAC 51: float glass 52: Adhesive film 53: laminated body S: shearing direction

[ Fig. 1 ] is a cross-sectional view showing a laminated body according to the first embodiment. [ Fig. 2 ] is a cross-sectional view showing a laminate according to a second embodiment. [ Fig. 3 ] is a cross-sectional view showing a laminated body according to a third embodiment. [ Fig. 4 ] is a cross-sectional view showing a laminated body according to a fourth embodiment. [Fig. 5] It is a perspective view for explaining the cross peel test. [FIG. 6] It is a plan view for explaining the measurement method of the adhesive force of a TAC polarizing plate.

Claims (11)

An adhesive film, which contains a thermoplastic resin and does not contain a plasticizer, or contains less than 20 parts by mass of a plasticizer relative to 100 parts by mass of the above thermoplastic resin, and the shear storage modulus of the above adhesive film at 20°C is: 3×10 ⁵ Pa or more, the adhesive force to the polycarbonate substrate measured by the following method is 100 N or more, <Adhesive force measurement method> Prepare an adhesive film with a size of 15 mm in length and 15 mm in width, and According to JIS K6735, two pieces of polycarbonate plate glass with a thickness of 2 mm, a length of 25 mm, and a width of 100 mm; through the above-mentioned adhesive film, the two pieces of polycarbonate plate glass are arranged in such a way that the length direction of each other is perpendicular to each other and stacked to form Cross; Afterwards, in such a way that the thickness of the above-mentioned adhesive film is fixed, using a spacer with the same thickness as the above-mentioned adhesive film, in a vacuum laminating machine, the two pieces of polycarbonate plate glass overlapping the above-mentioned adhesive film are placed on the Temporary crimping at 90°C and 0.1 MPa for 3 minutes; then, the two pieces of temporarily crimped polycarbonate plate glass are crimped at 90°C and 0.5 MPa for 1 hour to obtain a laminate Glass sample: for the obtained laminated glass sample, in the environment with a temperature of 23°C, peel the other piece of polycarbonate plate glass from one piece of polycarbonate plate glass at a speed of 10 mm/min in the direction perpendicular to the bonding surface, and measure For the maximum load (N) at this time, use the maximum load (N) as the adhesive force. For the adhesive film according to claim 1, the maximum peak temperature of tanδ at -50°C to 150°C is 10°C to 52°C. The adhesive film of claim 1 or 2 has a thickness of not less than 100 μm and not more than 2000 μm. The adhesive film according to any one of Claims 1 to 3, which has a thickness of not less than 100 μm and not more than 1000 μm. The adhesive film according to any one of claims 1 to 4, wherein the thermoplastic resin is a polyvinyl acetal resin. The adhesive film according to claim 5, wherein the polyvinyl acetal resin has a polyalkylene oxide structure represented by the following formula (1),

(In formula (1), A ¹ O is an oxyalkylene group with 2 to 6 carbons, m is the average repetition number, which is 4 to 200; R ¹ is an alkyl group with 1 to 8 carbons or a hydrogen atom; and , the oxyalkylene group may be a single type, or two or more types may be mixed; * is the bonding position with other groups). A laminate comprising the adhesive film according to any one of claims 1 to 6, and at least any one of an inorganic material substrate and an organic material substrate. The laminate according to claim 7, wherein the above-mentioned adhesive film is arranged so as to be attached to at least one of the inorganic material base material and the organic material base material. The laminate according to claim 7 or 8, wherein the inorganic material substrate is selected from the group consisting of an inorganic glass plate and an inorganic glass plate with at least any one of electrodes or sensors attached thereto. The laminate according to any one of Claims 7 to 9, wherein the above-mentioned organic material substrate is selected from polycarbonate plates, (meth)acrylic ((meth)acrylate) plates, and polyethylene terephthalate A group consisting of an ester film, a cyclic polyolefin film, a polycarbonate film, and a film having at least any one of electrodes or sensors attached to these films. The laminate according to any one of claims 7 to 10, comprising a pair of substrates selected from inorganic material substrates and organic material substrates, and the above-mentioned adhesive film disposed between the pair of substrates, and, The laminate has a multilayer structure of 3 or more layers.

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