WO2021029283A1 - Adhesive sheet for lamination, multilayered object, and production method for multilayered object - Google Patents

Abstract

Provided are an adhesive sheet for lamination which can handle a high temperature treatment, a multilayered object in which the adhesive sheet is used, and a production method for the multilayered object. The adhesive sheet for lamination includes a substrate that contains a polycarbonate and an adhesive layer that is provided on the substrate, and the glass transition temperature of the substrate is at least 160°C as measured by differential scanning calorimetry.

Description

Adhesive sheet for bonding, multilayer body and manufacturing method of multilayer body

The present invention relates to an adhesive sheet for bonding, a multilayer body, and a method for manufacturing a multilayer body. In particular, the present invention relates to an adhesive sheet for bonding using a base material containing polycarbonate.

Conventionally, it has been known that a polyolefin such as polypropylene or polyethylene is used as a base material for an adhesive sheet. However, the polyolefin sheet has a problem in terms of heat resistance. On the other hand, in order to improve the heat resistance, polyethylene terephthalate or the like can be considered. However, polyethylene terephthalate is required to be improved from the viewpoint of wet heat property and moldability. Therefore, it is considered to use polycarbonate as a base material of the pressure-sensitive adhesive sheet.

For example, in Patent Document 1, it is a laminate containing an adhesive sheet, and the front plate is a layer B having a polycarbonate resin as a main component and an A having a thermoplastic resin different from the polycarbonate resin as a main component. The layer is provided, and the total thickness of the A layer is 10 μm to 250 μm, and the ratio of the thickness (A) of the A layer 1 layer to the total thickness (T) of the A layer and the B layer ((A) / (T)) is 0.05 to 0.40, and the inside of the front plate and the adhesive sheet when the laminate of the front plate and the adhesive sheet is exposed for 120 hours in an environment of 85 ° C. and 85% humidity RH. A laminate characterized in that the stress (σ) is 0.47 MPa or less is disclosed.
Further, in Patent Document 2, when the adhesive force against glass at 23 ° C. is P and the adhesive force against glass at 80 ° C. is Q, the value represented by Q / P is 1 or more. The sheet is disclosed. Further, a laminate having the pressure-sensitive adhesive sheet and a polycarbonate base material on at least one surface of the pressure-sensitive adhesive sheet is also disclosed.

International Publication No. 2016/158827 JP-A-2017-200775

As described above, a pressure-sensitive adhesive sheet containing a base material containing polycarbonate and a pressure-sensitive adhesive layer provided on the base material has been studied. However, in recent years, the demand for adhesive sheets has been increasing, and the provision of new materials is required. In particular, recently, there is an increasing demand for adhesive sheets for bonding having excellent heat resistance that can be used for high temperature treatment.
An object of the present invention is to solve such a problem, which is an adhesive sheet containing a base material containing polycarbonate and an adhesive layer provided on the base material, and is bonded to be capable of high temperature treatment. It is an object of the present invention to provide an adhesive sheet for use, and a multilayer body and a method for producing a multilayer body using the adhesive sheet.

As a result of studies by the present inventors based on the above problems, it has been found that the above problems can be solved by adjusting the glass transition temperature of the base material to be 160 ° C. or higher. Specifically, the above problem was solved by the following means.
<1> A base material containing polycarbonate and
Including an adhesive layer provided on the substrate,
A bonding adhesive sheet having a glass transition temperature of 160 ° C. or higher as measured by differential scanning calorimetry of the base material.
<2> The polycarbonate contained in the base material contains 100 to 10% by mass of bisphenol AP type polycarbonate and 0 to 90% by mass of bisphenol A type polycarbonate, except that the total of bisphenol AP type polycarbonate and bisphenol A type polycarbonate is 100. The adhesive sheet for bonding according to <1>, which does not exceed% by mass.
<3> The adhesive sheet for bonding according to <1> or <2>, wherein the base material contains 10 to 90 parts by mass of polyarylate in 100 parts by mass of the resin component contained in the base material.
<4> The adhesive sheet for bonding according to any one of <1> to <3>, wherein the glass transition temperature measured by differential scanning calorimetry of the base material is 200 ° C. or less.
<5> The adhesive sheet for bonding according to any one of <1> to <4>, wherein the adhesive layer contains an acrylic adhesive.
<6> The adhesive sheet for bonding according to any one of <1> to <5>, wherein the adhesive layer contains a silicone adhesive.
<7> The adhesive sheet for bonding according to any one of <1> to <6>, wherein the adhesive layer contains a urethane adhesive.
<8> The adhesive sheet for bonding according to any one of <1> to <7>, wherein Re, which is an in-plane retardation of the base material, is 100 nm or less.
<9> The adhesive sheet for bonding according to any one of <1> to <8>, wherein the haze of the base material is 1.5% or less.
<10> The adhesive sheet for bonding according to any one of <1> to <9>, wherein the thickness of the base material is 30 μm or more and 200 μm or less.
<11> The adhesive sheet for bonding according to any one of <1> to <10>, wherein the thickness of the adhesive layer is 10 μm or more and 70 μm or less.
<12> In a peeling test in which the sheet is laminated on a polycarbonate mirror film on the adhesive layer side and peeled in a direction of 180 ° in accordance with JIS Z0237 under the condition of 152 mm / min, 0.001 to 0.001 to The adhesive sheet for bonding according to any one of <1> to <11>, which exhibits a peeling force of 3N / 25 mm.
<13> The adhesive sheet for bonding according to any one of <1> to <12>, which has a primer layer between the base material and the adhesive layer.
<14> A multilayer body in which the adhesive sheet for bonding according to any one of <1> to <13> is adhered to at least a part of the surface of the resin molded product on the adhesive layer side.
<15> The multilayer body according to <14>, wherein the resin molded body is a resin sheet.
<16> The multilayer body according to <14> or <15>, wherein the resin molded body contains polycarbonate.
<17> The multilayer body according to <14> or <15>, wherein the resin molded body contains polyimide.
<18> A method for producing a multilayer body, which comprises attaching the adhesive sheet for bonding according to any one of <1> to <13> to a resin molded body.

INDUSTRIAL APPLICABILITY According to the present invention, it has become possible to provide an adhesive sheet for bonding that can be treated at a high temperature, and a multilayer body and a method for manufacturing a multilayer body using the adhesive sheet.

It is a schematic diagram which shows an example of the layer structure of the adhesive sheet for bonding of this invention.

The contents of the present invention will be described in detail below. In addition, in this specification, "-" is used in the meaning which includes the numerical values described before and after it as the lower limit value and the upper limit value.
In the present specification, various physical property values and characteristic values shall be at 23 ° C. unless otherwise specified.
As used herein, the term "sheet" refers to a thin, flat product whose thickness is small for its length and width, and includes "film". Further, the "sheet" in the present specification may be a single layer or a multi-layer.
As used herein, the term (meth) acrylate may include acrylate and methacrylate, respectively.

[Adhesive sheet for bonding]
The adhesive sheet for bonding of the present invention (hereinafter, may be referred to as "sheet" or "adhesive sheet") includes a base material containing polycarbonate and an adhesive layer provided on the base material, and the base material. The glass transition temperature measured by the differential scanning calorimetry is 160 ° C. or higher. With such a configuration, it becomes possible to provide an adhesive sheet for bonding that can be used for high temperature treatment. Further, it is possible to obtain an adhesive sheet for bonding which is excellent in both adhesiveness and removability to other members (for example, a resin molded body described later) and also has excellent transparency. In this way, the adhesive sheet for bonding obtained by providing the adhesive layer on the base material having a glass transition temperature of 160 ° C. or higher is a product that requires high temperature treatment and a reliability test such as high temperature treatment at the time of inspection. Can be used as a protective film for products that require.

The pressure-sensitive adhesive sheet of the present invention has an pressure-sensitive adhesive layer provided on the base material as an essential component. As a preferred embodiment of the present invention, as shown in FIG. 1, as the pressure-sensitive adhesive sheet 10 of the present invention, a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer 12, a primer layer 16 and a base material 20 is exemplified.
In the present invention, the adhesive layer 12, the primer layer 16, and the base material 20 may each have one layer or two or more layers.

In a preferred embodiment of the present invention, at least one layer of the pressure-sensitive adhesive layer contained in the pressure-sensitive adhesive sheet of the present invention may be provided on the surface of the base material, and a primer layer or the like may be provided between the base material and the pressure-sensitive adhesive layer. Layer may be provided. In the pressure-sensitive adhesive sheet of the present invention, the pressure-sensitive adhesive layer is preferably provided on the surface of the primer layer opposite to the base material side.

In a preferred embodiment of the invention, the primer layer is usually provided between the substrate and the adhesive layer. By having the primer layer, impurities derived from polycarbonate contained in the base material may invade the adhesive layer to reduce the adhesiveness, deteriorate or decompose the base material layer, or generate bubbles. Can effectively suppress this.
The primer layer is preferably arranged between the base material and the adhesive layer, and is provided so that one surface of the primer layer is in contact with the surface of the base material and the other surface is in contact with the surface of the adhesive layer. Is more preferable. However, other layers may be provided between the primer layer and the substrate and / or between the primer layer and the adhesive layer.

Examples of other layers in the pressure-sensitive adhesive sheet of the present invention include a hard coat layer, an ultraviolet absorption layer, an antistatic layer, an antireflection layer, an antiblock layer, an index matching layer, a print coat layer and a release layer.

The details of the base material, adhesive layer, primer layer, and hard coat layer will be described below.

<Base material>
In the pressure-sensitive adhesive sheet of the present invention, the base material contains polycarbonate, and the glass transition temperature of the base material measured by differential scanning calorimetry is 160 ° C. or higher. By setting the glass transition temperature to the above lower limit value or more, a bonding adhesive sheet having excellent heat resistance can be obtained.
The glass transition temperature of the base material is preferably 160 ° C. or higher, more preferably 161 ° C. or higher. The glass transition temperature of the base material is preferably 200 ° C. or lower, more preferably 190 ° C. or lower, and even more preferably 180 ° C. or lower. The glass transition temperature is measured according to the method described in Examples described later (hereinafter, the same applies to the glass transition temperature).
Examples of the means for setting the glass transition temperature of the base material within the above range include selecting the type of polycarbonate to be used, adding another resin, and the like. Specific examples thereof include the addition of polycarbonate having a high glass transition temperature such as bisphenol AP type polycarbonate, and the addition of another resin having a high glass transition temperature such as polyarylate. These details will be described later.

The substrate used in the present invention preferably has an in-plane retardation (Re) of 100 nm or less, more preferably 80 nm or less, further preferably 60 nm or less, and even more preferably 45 nm or less. It is even more preferably 40 nm or less. By setting the value to the upper limit or less, it is expected to be applied to liquid crystal member applications, and shrinkage during high temperature treatment is also reduced. The lower the lower limit, the more desirable it is, but 0.1 nm or more is practical.

The haze of the base material is preferably 1.5% or less, more preferably 1.2% or less, and even more preferably 1.0% or less. The lower limit is not particularly limited, and 0% is ideal, but 0.01% or more, and even 0.1% or more, sufficiently satisfy the performance requirements.
In this specification, haze adopts a value measured based on the method described in Examples described later.

The thickness of the base material is not particularly limited, but is preferably 30 μm or more, more preferably 35 μm or more, further preferably 40 μm or more, and further preferably 50 μm. By setting the value to the lower limit or more, the material strength (tensile strength, etc.) of the pressure-sensitive adhesive sheet tends to be further improved. The thickness of the base material is preferably 200 μm or less, more preferably 150 μm or less, and may be 120 μm or less. By setting the value to the upper limit or less, it is possible to more effectively suppress the problem that the base material is easily peeled off due to the rigidity of the base material.

Next, the material of the base material of the present invention will be described.
The base material used in the present invention contains polycarbonate.
The type of polycarbonate contained in the base material includes a carbonate bond in the molecular main chain- [OR-OC (= O)]-unit (R is a hydrocarbon group, specifically, an aliphatic group. Aromatic polycarbonate is preferable as long as it contains a group, an aromatic group, or a group containing both an aliphatic group and an aromatic group, and further having a linear structure or a branched structure). Polycarbonates having a bisphenol skeleton are more preferred. By using such polycarbonate, better heat resistance and toughness are achieved. The polycarbonate having a bisphenol skeleton preferably has 90 mol% or more of all the constituent units having a bisphenol skeleton.

The viscosity average molecular weight (Mv) of polycarbonate is preferably 10,000 or more, more preferably 12,000 or more, still more preferably 15,000 or more, still more preferably 20,000 or more. Is. By setting the value to the lower limit or more, the durability of the base material tends to be further improved. The upper limit of the viscosity average molecular weight (Mv) of the polycarbonate is preferably 45,000 or less, more preferably 40,000 or less, and further preferably 34,000 or less. By setting the value to the upper limit or less, the molding processability of the base material tends to be further improved.
For the viscosity average molecular weight (Mv), methylene chloride was used as a solvent, and the ultimate viscosity [η] (unit: dL / g) at a temperature of 25 ° C. was determined using an Ubbelohde viscometer, and the viscosity formula of Schnell, that is, η =. It means a value calculated from 1.23 × 10 ^-4 × Mv ^0.83 .
When two or more types of polycarbonate are used, the viscosity average molecular weight of the mixture is used (hereinafter, various physical properties are considered in the same manner).

The base material used in the present invention may consist only of polycarbonate or may contain other resin components. Examples of other resins include polyarylate.
The total amount of the resin component in the base material is preferably 90% by mass or more, more preferably 95% by mass or more, and may be 99% by mass or more. The resin component may contain only one type of polycarbonate, or may contain two or more types of polycarbonate. Further, when a resin component other than polycarbonate (for example, polyarylate) is contained, only one type of the other resin component may be contained, or two or more types may be contained. In addition, examples of components other than the resin component include additives described later.

In the first embodiment of the base material used in the present invention, the polycarbonate contains 100 to 10% by mass of bisphenol AP type polycarbonate and 0 to 90% by mass of bisphenol A type polycarbonate (however, bisphenol AP type polycarbonate and bisphenol A type). The total amount of polycarbonate does not exceed 100% by mass). In the first embodiment of the base material, it is preferable to contain 20 to 90% by mass of bisphenol AP type polycarbonate and 10 to 80% by mass of bisphenol A type polycarbonate, and 30 to 80% by mass of bisphenol AP type polycarbonate and bisphenol A type. More preferably, it contains 20 to 70% by mass of polycarbonate. By adopting such a form, it is possible to have excellent heat resistance and reduce the in-plane retardation of the obtained sheet.
In the present embodiment, the total amount of polycarbonate with respect to the base material is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more.
Only one type of bisphenol AP type polycarbonate and bisphenol A type polycarbonate may be contained, or two or more types may be contained.
Hereinafter, the bisphenol AP type polycarbonate and the bisphenol A type polycarbonate will be described in detail.

<< Bisphenol AP type polycarbonate >>
The bisphenol AP type polycarbonate refers to a resin having a carbonate unit derived from bisphenol AP and a derivative thereof, and preferably has a structural unit represented by the following formula (A-1). * In the formula represents the connection position.

In the formula (A-1), R ¹ to R ⁴ are independently a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group having 1 to 9 carbon atoms (preferably 1 to 3), and 6 carbon atoms. To 12 (preferably 6 to 10) aryl groups, 1 to 5 (preferably 1 to 3) alkoxy groups, 2 to 5 (preferably 2 or 3) alkenyl groups or 7 to 17 carbon atoms. Represents an arylyl group (preferably 7-11). l represents an integer from 0 to 5. m and n each independently represent an integer of 0 to 4. * Represents the bond position.

The structural unit represented by the formula (A-1) is preferably the structural unit represented by the following formula (A-2). * In the formula represents the connection position.

R ¹ , R ² , R ³ , R ⁴ , l, m, and n are synonymous with those defined by the equation (A-1).

The structural unit represented by the formula (A-2) is preferably the structural unit represented by the following formula (A-3). * In the formula represents the connection position.

The content of the structural unit represented by the formula (A-1) in the bisphenol AP-type polycarbonate is preferably 70 mol% or more, more preferably 80 mol% or more, and 90 mol% or more of all the structural units. It is more preferably mol% or more. The upper limit value is not particularly limited, and 100 mol% may be a structural unit represented by the formula (A-1). The bisphenol AP-derived structural unit may be composed of only one type or two or more types. Particularly preferred as the bisphenol AP-type polycarbonate is a resin in which substantially the entire amount is composed of the structural unit of the formula (A-1). The substantially total amount here specifically refers to 99.0 mol% or more, preferably 99.5 mol% or more, and more preferably 99.9 mol% or more.
The bisphenol AP type polycarbonate may have other constituent units different from the carbonate unit derived from bisphenol AP and its derivatives. Examples of the dihydroxy compound constituting such another structural unit include the aromatic dihydroxy compound described in paragraph 0014 of JP-A-2018-154819, and the contents thereof are incorporated in the present specification. ..

The method for producing the bisphenol AP-type polycarbonate is not particularly limited, and any method can be adopted. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer.

In the present invention, the viscosity average molecular weight of the bisphenol AP-type polycarbonate is preferably 10,000 to 28,000. As the lower limit value, it is more preferably 11,000 or more, further preferably 12,000 or more, and further preferably 13,000 or more. The upper limit is more preferably 25,000 or less, further preferably 23,000 or less, and even more preferably 20,500 or less. By setting the viscosity average molecular weight as described above, it is possible to impart excellent heat resistance while maintaining the transparency of the obtained base material and the pressure-sensitive adhesive sheet. By using such a bisphenol AP type polycarbonate, it becomes easy to set the viscosity average molecular weight of the entire polycarbonate component in a desired range.

The glass transition temperature (Tg) of the bisphenol AP-type polycarbonate is preferably 172 ° C. or higher, more preferably 175 ° C. or higher, and even more preferably 180 ° C. or higher. The upper limit is preferably 210 ° C. or lower, more preferably 200 ° C. or lower, and even more preferably 190 ° C. or lower. By using such a bisphenol AP type polycarbonate, the glass transition temperature of the entire polycarbonate component can be easily set in a desired range.

<< Bisphenol A Polycarbonate >>
Bisphenol A type polycarbonate refers to a resin having a carbonate unit derived from bisphenol A and its derivative.
The content of the carbonate unit derived from bisphenol A and its derivative in the bisphenol A type polycarbonate is preferably 70 mol% or more, more preferably 80 mol% or more, and 90 mol% or more in the total constituent units. Is more preferable. The upper limit is not particularly limited, and 100 mol% may be a carbonate unit derived from bisphenol A and its derivative. Particularly preferably, the bisphenol A type polycarbonate is a resin composed of substantially the entire amount of bisphenol A and its derivatives derived from carbonate units. The substantially total amount here specifically refers to 99.0 mol% or more, preferably 99.5 mol% or more, and more preferably 99.9 mol% or more.
The bisphenol A type polycarbonate may have a structural unit other than the carbonate unit derived from bisphenol A and its derivative. Examples of the dihydroxy compound constituting such another structural unit include the aromatic dihydroxy compound described in paragraph 0014 of JP-A-2018-154819, and the contents thereof are incorporated in the present specification. ..

The method for producing bisphenol A type polycarbonate is not particularly limited, and any method can be adopted. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer.

In the present invention, the viscosity average molecular weight of the bisphenol A type polycarbonate is preferably 10,000 to 45,000. The lower limit value is more preferably 10,200 or more, further preferably 10,500 or more, and further preferably 10,750 or more. By setting the value to the above lower limit or more, the durability of the base material tends to be improved. The upper limit is more preferably 43,000 or less, further preferably 40,000 or less, and further preferably 35,000 or less. By setting the value to the upper limit or less, the molding processability tends to be improved.

The second embodiment of the base material used in the present invention is a form containing 10 to 90 parts by mass of polyarylate in 100 parts by mass of the resin component contained in the base material. With such a form, a base material exhibiting excellent yield strength can be obtained. In the second embodiment of the base material, it is preferable that 20 to 80 parts by mass of polyarylate is contained in 100 parts by mass of the resin component contained in the base material, and polyarylate is contained in 100 parts by mass of the resin component contained in the base material. Is more preferably contained in an amount of 25 to 75 parts by mass.
In the second embodiment of the base material, only one kind of polycarbonate and polyarylate may be contained, or two or more kinds may be contained.
In the second embodiment of the base material, the total of polycarbonate and polyarylate in the base material occupies preferably 90% by mass or more, more preferably 95% by mass or more, and further preferably 98% by mass or more of the base material.

<< Polycarbonate >>
In the second embodiment, the polycarbonate may be any polycarbonate, but preferably contains bisphenol A type polycarbonate. The bisphenol A type polycarbonate has the same meaning as the bisphenol A type polycarbonate described in the first embodiment of the base material, and the preferable range is also the same.

<< Polyarylate >>
The polyarylate used in the present invention is preferably an aromatic polyester composed of a structural unit derived from an aromatic dicarboxylic acid and a structural unit derived from bisphenol.
Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, benzophenonedicarboxylic acid, and 4,4'-diphenyldicarboxylic acid. , 3,3'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid and the like, and terephthalic acid and isophthalic acid are more preferable.
Examples of the bisphenol include 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, and 2,2-bis (4-hydroxy-3,). 5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenylsulfide , 4,4'-Dihydroxydiphenylketone, 4,4'-dihydroxydiphenylmethane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1, Examples thereof include 1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane. These compounds may be used alone or in combination of two or more.

More specifically, the polyarylate preferably contains a structural unit represented by the following formula (B-1) and / or a structural unit represented by the following formula (B-2). * In the formula represents the connection position.
Equation (B-1)

In formula (B-1), X ⁸ represents the following structure.

R ⁵ and R ⁶ are alkyl groups or hydrogen atoms, preferably at least one is a methyl group, and more preferably both are methyl groups.
The structural unit represented by the formula (B-1) is formed from, for example, at least one of bisphenol A and its derivatives, terephthalic acid and isophthalic acid, and at least one of their derivatives. The molar ratio of terephthalic acid to isophthalic acid is preferably 40 to 60: 60 to 40.

Equation (B-2)

In formula (B-2), R ⁸ independently contains a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group having 1 to 9 carbon atoms (preferably 1 to 3), and 6 carbon atoms. ~ 12 (preferably 6-10) aryl groups, 1-5 (preferably 1-3) alkoxy groups, 2-5 (preferably 2 or 3) alkenyl groups or 7-17 carbon atoms. Represents an aralkyl group (preferably 7-11). q represents an integer from 1 to 5.
R ⁸ is preferably a hydrogen atom or an alkyl group having 1 to 9 carbon atoms (preferably 1 to 3) independently of each other, and more preferably a hydrogen atom or a methyl group.

The structural unit represented by the formula (B-2) is preferably the structural unit represented by the formula (B-3).
Equation (B-3)

Wherein (B-3), ^{R 8} has the same meaning as ^{R 8} in the formula (B-2), and preferred ranges are also the same.
The structural unit represented by the formula (B-3) is formed from, for example, at least one of bisphenol TMC and its derivatives, terephthalic acid and isophthalic acid, and at least one of their derivatives. The molar ratio of terephthalic acid to isophthalic acid is preferably 40 to 60: 60 to 40.

The first embodiment of the polyarylate used in the present invention is a form containing 90 mol% or more of the structural units represented by the formula (B-1) in all the structural units excluding both ends.
In the second embodiment of the polyarylate used in the present invention, the structural unit represented by the formula (B-1) and the structural unit represented by the formula (B-2) are arranged in a molar ratio of 90 to 40:10. It is a form containing at a ratio of to 60, more preferably at a ratio of 90 to 51:10 to 49, and more preferably at a ratio of 85 to 55:15 to 45. The structural unit represented by the formula (B-1) and the structural unit represented by the formula (B-2) may be included in the same polyarylate, or the structural unit represented by the formula (B-1). It may be a blend of a polyarylate containing a unit and a polyarylate containing a structural unit represented by the formula (B-2). Further, in the second embodiment, the polyarylate used in the present invention is a total of the structural units represented by the formula (B-1) and the structural units represented by the formula (B-2) at both ends. It is more preferable to contain 90 mol% or more of all the constituent units excluding.

The weight average molecular weight of the polyarylate is preferably 25,000 or more, more preferably 30,000 or more, further preferably 35,000 or more, and even more preferably 37,000 or more. It may be 40,000 or more. The upper limit of the weight average molecular weight of the polyarylate is preferably 80,000 or less, more preferably 60,000 or less, and further preferably 50,000 or less.

The weight average molecular weight of polyarylate was measured by gel permeation chromatography as follows.
An LC-20AD system (manufactured by Shimadzu Corporation) was used as a gel permeation chromatography apparatus, and LF-804 (manufactured by Shodex) was connected and used as a column. The column temperature was 40 ° C. As the detector, an RI detector of RID-10A (manufactured by Shimadzu Corporation) was used. Chloroform was used as the eluent, and the calibration curve was prepared using standard polystyrene manufactured by Tosoh Corporation.
If the gel permeation chromatography device, column, and detector are difficult to obtain, the measurement is performed using another device having equivalent performance.

The glass transition temperature measured by a differential scanning calorimeter of polyarylate is preferably more than 160 ° C., more preferably 170 ° C. or higher, further preferably 180 ° C. or higher, and 190 ° C. or higher. Is more preferable. The upper limit of the glass transition temperature is preferably 250 ° C. or lower, and may be 240 ° C. or lower, 230 ° C. or lower, 220 ° C. or lower, or 200 ° C. or lower. By setting it to the above lower limit value or more, the heat resistance of the obtained base material can be further improved, and by setting it to the above upper limit value or less, the melt viscosity can be set to a more appropriate range.

The base material may also contain additives in addition to the above resin components. Examples of the additive include at least one selected from the group consisting of heat stabilizers, antioxidants, flame retardants, flame retardants, ultraviolet absorbers, mold release agents and colorants. Further, an antistatic agent, a near-infrared ray shielding agent, a light diffusing agent, a fluorescent whitening agent, an antifogging agent, a fluidity improving agent, a plasticizer, a dispersant, an antibacterial agent and the like may be added to the substrate.
Examples of the antioxidant include a phenol-based antioxidant, an amine-based antioxidant, a phosphorus-based antioxidant, and a thioether-based antioxidant. Among them, in the present invention, phosphorus-based antioxidants and phenol-based antioxidants (more preferably hindered phenol-based antioxidants) are preferable. Phosphorus-based antioxidants are particularly preferable because they are excellent in hue of the base material. As the phosphorus-based antioxidant, the description in paragraphs 0098 to 0106 of JP-A-2018-178075 can be referred to, and the content thereof is incorporated in the present specification.
The total amount of the additive in the base material is preferably 0 to 10% by mass, more preferably 0 to 5% by mass.

Next, the layer structure of the base material will be described.
The base material may be a single layer or may be a multi-layer. In the case of a multi-layer structure, for example, an acrylic resin such as a poly (meth) methyl crylate resin (PMMA: methyl polyacrylate and / or polymethyl methacrylate) is formed on a layer of polycarbonate (PC). Examples thereof include those in which a layer of polycarbonate (PC) is further laminated on a layer of polycarbonate (PC). The base material used in the present invention is preferably a single layer.

<Adhesive layer>
As described above, the sheet of the present invention includes an adhesive layer provided on the base material.
The type of the adhesive layer is not particularly limited, but preferably contains at least one of an acrylic pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, and a urethane pressure-sensitive adhesive. By using these adhesives, higher adhesiveness and, for example, appropriate adhesion to the primer layer can be realized.
Further, the adhesive layer may have re-peelability, and the adhesive layer having re-peelability can be re-adhered even if it is once peeled from the sticking material.

The acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive containing an acrylic polymer, and specific examples thereof include Fine Tack (CT-3088, CT-3850, CT-6030, CT-5020, CT-5030) and Quick Master manufactured by DIC. (SPS-900-IV, Quick Master SPS-1040NT-25), and the adhesive Olipine manufactured by Toyochem Co., Ltd. can be mentioned.
The silicone pressure-sensitive adhesive is a pressure-sensitive adhesive containing a silicone-based polymer, and specific examples thereof include a polymer manufactured by KR-3704 (main agent) and CAT-PL-50T (platinum catalyst) manufactured by Shin-Etsu Chemical Co., Ltd. Can be mentioned.
The urethane pressure-sensitive adhesive is a pressure-sensitive adhesive containing a urethane-based polymer, and specific examples thereof include a pressure-sensitive adhesive Olipine manufactured by Toyochem Co., Ltd.
In the present specification, the polymer means a compound having a number average molecular weight of 1000 or more, and preferably a compound having a number average molecular weight of 2000 or more.

In addition to the above, the adhesive layer includes the pressure-sensitive adhesive layer described in paragraphs 0026 to 00053 of JP-A-2017-200775 and paragraphs 0056-0060 of JP2013-020130, as long as the gist of the present invention is not deviated. , The adhesive sheet of International Publication No. 2016/158827, the adhesive layer of paragraphs 0031 to 0032 of JP2016-182791A, and the rubber-based adhesive of paragraphs 0057 to 0084 of JP2015-147837. Agent layers may also be employed and these contents are incorporated herein.

The thickness of the adhesive layer is not particularly limited, but is preferably 10 μm or more, more preferably 25 μm or more, further preferably 35 μm or more, and may be 40 μm or more. The thickness of the adhesive layer is preferably 70 μm or less, more preferably 60 μm or less. Within the above range, more appropriate adhesive properties and adhesive strength are achieved.

Next, the peeling force of the adhesive layer will be described.
In the present invention, the adhesive for bonding includes a base material containing polycarbonate and an adhesive layer provided on the base material, and the glass transition temperature measured by differential scanning calorimetry of the base material is 160 ° C. or higher. A peeling test in which the sheet is laminated on a polycarbonate mirror film having a thickness of 0.1 (mm) on the adhesive layer side and peeled off in a 180 ° direction under the condition of 152 mm / min in accordance with JIS Z0237. It is preferable to exhibit a peeling force of 0.001 to 4.5 N / 25 mm. By setting the value to the lower limit or more, the adhesive strength tends to be further improved. The peeling force is more preferably 0.005 N / 25 mm or more, and further preferably 0.01 N / 25 mm or more. Further, the peeling force is more preferably 3N / 25mm or less, further preferably 1N / 25mm or less, further preferably 0.8N / 25mm or less, and 0.7N / 25mm or less. It is even more preferably 0.5 N / 25 mm or less, and it may be 0.2 N / 25 mm or less. By setting the peeling force to 3N / 25 mm or less and further to 1N / 25 mm or less, an adhesive sheet having excellent re-peelability can be obtained.
The peeling force is measured according to the method described in Examples described later.

The peeling force can be controlled by the composition of the adhesive layer. For example, in the case of a silicone-based adhesive layer, the peeling force can be adjusted by the main chain structure, terminal structure, branched structure, molecular weight, etc. of the polyorganosiloxane formed. Further, in the case of a urethane-based adhesive layer, the peeling force can be adjusted by the main chain structure and molecular weight of the polyol and polyisocyanate, and their ratios. Further, in the case of an acrylic adhesive layer, the peeling power depends on the monomer structure and molecular weight of the acrylic-containing resin, the copolymerization ratio, the main chain structure and molecular weight of the polyisocyanate, and the ratio of the acrylic-containing resin and the polyisocyanate. Adjustment is possible.
Further, by combining pressure-sensitive adhesives having different adhesive strengths, it is possible to form an adhesive layer having an arbitrary peeling power.

<Primer layer>
As described above, the pressure-sensitive adhesive sheet of the present invention may have a primer layer. The primer layer is provided between the base material layer and the adhesive layer, and has an effect of enhancing the adhesiveness between the adhesive layer and the base material layer. In addition, it is possible to suppress chemical cracks in the base material due to the solvent used when forming the adhesive layer.
The primer layer preferably contains a urethane (meth) acrylate resin. By using a urethane (meth) acrylate resin, an adhesive sheet having more excellent heat resistance can be obtained.

<< Urethane (meth) acrylate resin >>
(Urethane (meth) acrylate resin containing the molecular structure of the cyclic skeleton)
As the urethane (meth) acrylate resin, a urethane (meth) acrylate resin containing a molecular structure having a cyclic skeleton is preferable. More specifically, a polymer of an isocyanate compound and an acrylate compound having a cyclic skeleton is mentioned as a specific example of a preferable urethane (meth) acrylate. The urethane (meth) acrylate resin, which may have a molecular structure having a cyclic skeleton, is preferably an ultraviolet curable type.

The isocyanate compound is, for example, an aromatic isocyanate which may have a substituent which is an alkyl group such as a methyl group, preferably an aromatic isocyanate having a total carbon number of 6 to 16, and more preferably a carbon number of 7. Aromatic isocyanates of to 14 to 14, particularly preferably aromatic isocyanates having 8 to 12 carbon atoms are used.
As the above-mentioned isocyanate, it is preferable that it is an aromatic isocyanate, but an aliphatic or alicyclic isocyanate is also used.

Examples of the (meth) acrylate compound include pentaerythritol triacrylate (PETA), dipentaerythritol pentaacrylate (DPPA), hydroxypropyl (meth) acrylate (hydroxypropyl acrylate: HPA) and the like.
Further, as the (meth) acrylate compound, a compound having a (meth) acryloyloxy group and a hydroxy group, for example, a monofunctional (meth) acrylic compound having a hydroxy group can also be used.

A preferable specific example of the above-mentioned polymer of isocyanate compound and (meth) acrylate compound, that is, urethane (meth) acrylate resin is a polymer of xylylene diisocyanate (XDI) and pentaerythritol triacrylate (PETA), XDI. Polymer of dipentaerythritol pentaacrylate (DPPA), polymer of dicyclohexylmethane diisocyanate (H12MDI) and PETA, polymer of isophorone diisocyanate (IPDI) and PETA, XDI and hydroxypropyl (meth) acrylate (HPA) ), And the like.

Further, as the urethane (meth) acrylate containing a cyclic skeleton, a polymer containing a polyol compound as a constituent unit in addition to the above-mentioned isocyanate compound and (meth) acrylate compound can also be mentioned. Examples of the polyol compound (polyhydric alcohol) include compounds having two or more hydroxy groups in one molecule.

Preferred specific examples of the above-mentioned urethane (meth) acrylate resin include a polymer of tricyclodidecanedimethanol (TCDDM), IPDI and PETA, a polymer of TCDDM, H12MDI and PETA, and among these polymers, PETA. Alternatively, or a polymer containing DPPA as a constituent unit together with PETA, a polymer of xylylene diisocyanate (XDI) and hydroxypropyl (meth) acrylate (HPA), and the like can be mentioned.

The urethane (meth) acrylate containing a polyol compound as a constituent unit in addition to the isocyanate compound and the compound having a (meth) acryloyloxy group and a hydroxy group may contain at least a component represented by the following formula (I). preferable.
(A ³ ) -O (O =) CHN-A ^2- HNC (= O) O-A ^1- O (O =) CNH-A ^2- NH- (= O) O- (A ³ ) ... (I)
In formula (I)
A ¹ is an alkylene group derived from the above-mentioned polyol compound.
A ² is an alkylene group derived from the above-mentioned isocyanate compound independently.
A ³ is an alkyl group derived from the above-mentioned compound having a (meth) acryloyloxy group and a hydroxy group, respectively.

Preferred specific examples of the urethane (meth) acrylate contained in the above-mentioned resin component include ethylene glycol, pentaerythritol triacrylate, and the following compounds containing a structural unit derived from isophorone diisocyanate. In the following formula, the value of n is 0 to 10, preferably 1 to 5, and more preferably 1 to 3.

In the urethane (meth) acrylate resin, the ratio of the structural unit derived from the compound having a (meth) acryloyloxy group and the hydroxy group to the structural unit derived from isocyanate is 99: 1 to 30:70 (mass ratio). It is preferably 97: 3 to 60:40, and even more preferably 95: 5 to 80:20.

(Urethane (meth) acrylate containing (meth) acrylate)
Preferred specific examples of the urethane (meth) acrylate resin are urethane (meth) acrylate and (meth) acrylate (referring to those other than urethane (meth) acrylate, preferably (meth) acrylate having a molecular weight of 1000 or less, the same applies hereinafter). Those including and can be mentioned. A more preferable specific example of such a urethane (meth) acrylate resin is one containing a mixture of a hexafunctional urethane (meth) acrylate and a bifunctional (meth) acrylate.

In the urethane (meth) acrylate resin, the ratio of urethane (meth) acrylate to (meth) acrylate is preferably 99: 1 to 30:70 (mass ratio), and more preferably 97: 3 to 60:40. It is more preferably 95: 5 to 80:20.

As described above, when the primer layer is formed from a mixture of urethane (meth) acrylate and (meth) acrylate, the adhesion to the substrate and the bendability of the primer layer are improved.

In the present invention, the urethane (meth) acrylate is preferably urethane acrylate.

The material forming the primer layer, that is, the primer paint, is charged as a resin component other than urethane (meth) acrylate and (meth) acrylate, for example, epoxy (meth) acrylate, acrylic (meth) acrylate, and a component other than the resin component. An inhibitor, an ultraviolet absorber (ultraviolet shielding agent), a near-infrared shielding agent, a light diffusing agent such as silica or metal particles, or the like may be added. The total amount of these is preferably 5% by mass or less of the solid content (component serving as the primer layer) of the primer coating material.

Further, the primer coating material may contain either a leveling agent or a photopolymerization initiator. Further, the primer coating material may contain a solvent. The solvent of the primer coating material is preferably one that does not affect the resin component of the base material, and particularly preferably propylene glycol monomethyl ether or the like.
By adding a leveling agent to the primer paint, the surface of the coating film during the drying process is oriented, the surface tension of the coating film is made uniform and reduced, floating mottle and repelling are prevented, and the wettability to the object to be coated is prevented. Can be improved. As the leveling agent, for example, a silicone-based surfactant, an acrylic-based surfactant, a fluorine-based surfactant, or the like is preferably used.

The primer coating material preferably contains 80% by mass or more of the resin component, more preferably 90% by mass or more of the resin component, based on the mass of the solid content (component serving as the primer layer) of the primer coating material. More preferably, the resin component is contained in an amount of 95% by mass or more. The resin component preferably contains 80% by mass or more of urethane (meth) acrylate.

As the primer layer, in addition to the above, the description of paragraphs 0012 to 0019 and 0029 to 0030 of JP-A-2016-182791 and the description of paragraphs 0051 to 0056 of JP-A-2015-147738 can be taken into consideration. Incorporated herein.

The thickness of the primer layer is not particularly limited, but is preferably 2 μm or more, and more preferably 2.5 μm or more. By setting the value to the lower limit or more, it is possible to more effectively prevent the base material from being whitened by the solvent when the pressure-sensitive adhesive layer is applied. The thickness of the primer layer is preferably 10 μm or less, more preferably 7 μm or less, and even more preferably 5 μm or less. By setting the value to the upper limit or less, it is possible to prevent cracks from occurring during bending or the like.

<Hard coat layer>
As described above, the pressure-sensitive adhesive sheet of the present invention may have a hard coat layer. By providing the hard coat layer, the surface hardness of the adhesive sheet tends to be improved. The thickness of the hard coat layer is not particularly limited, but is preferably 1 to 10 μm, more preferably 2 to 8 μm, and even more preferably 3 to 7 μm.
The hard coat layer is preferably formed on the surface of the base material on which the primer layer is not laminated.
The hard coat layer is preferably formed by a hard coat treatment applied to the surface of a base material or the like. That is, it is preferable to laminate the hard coat layer by applying a hard coat material that can be heat-cured or cured by active energy rays and then curing the material.
Examples of the coating material to be cured by using active energy rays include a resin composition composed of one or more such as a monofunctional or polyfunctional (meth) acrylate monomer or an oligomer, and more preferably a urethane (meth) acrylate oligomer. Examples include resin compositions. It is preferable to add a photopolymerization initiator as a curing catalyst to these resin compositions.
Examples of the thermosetting resin paint include polyorganosiloxane-based paints and crosslinked acrylic-based paints. Some of such resin compositions are commercially available as hard coat agents for acrylic resins or polycarbonates, and may be appropriately selected in consideration of suitability with the coating line.
As the hard coat layer, paragraphs 0045 to 0055 of JP2013-020130, paragraphs 0073 to 0076 of JP2018-103518, and paragraphs 0062-0082 of JP2017-2137771 These contents are incorporated herein by reference.

[Manufacturing method of adhesive sheet]
In the production of the pressure-sensitive adhesive sheet, it is preferable that a base material is first formed. In the production of a base material, a resin composition for molding a base material containing polycarbonate is processed into a sheet shape (film shape) by a known method. Specifically, it can be molded by extrusion molding or cast molding. In the present invention, it is particularly preferable to melt and extrude a resin composition for molding a base material containing polycarbonate containing no solvent to obtain a base material. As an example of extrusion molding, pellets, flakes or powders of a resin composition are melted by an extruder, kneaded, extruded from a T-die or the like, and the obtained semi-molten sheet is cooled and solidified while being pressed by a roll. A method of forming a sheet can be mentioned. Moreover, you may use the commercially available polycarbonate film.

The pressure-sensitive adhesive sheet can be produced by using the above-mentioned base material containing polycarbonate, for example, by a production method including a primer layer forming step and a pressure-sensitive adhesive layer forming step as follows.
In the primer layer forming step, a primer coating material (primer solution) is applied on the surface of the base material and cured to form a primer layer.
Further, in the pressure-sensitive adhesive layer forming step, a pressure-sensitive adhesive is applied and cured on the surface of the formed primer layer on the side opposite to the side in contact with the base material to form a pressure-sensitive adhesive layer.
As a method for curing the primer paint or the pressure-sensitive adhesive, a method such as photo-curing and thermosetting can be adopted.

[Multilayer]
The multilayer body of the present invention is characterized in that the pressure-sensitive adhesive sheet of the present invention is adhered to at least a part of the surface of the resin molded product on the pressure-sensitive adhesive layer side. Here, the resin molded body is molded from a resin and means a body to be adhered to which the adhesive sheet of the present invention is bonded. The shape of the resin molded product is not particularly defined, and may be a part or a finished product, and may have a smooth surface, irregularities, or a more complicated shape. In the present invention, a form in which the resin molded body is a resin sheet is exemplified.
The resin molded body is preferably a material having excellent heat resistance and transparency. The resin molded product preferably contains an amorphous resin having a Tg of 160 ° C. or higher, preferably contains polycarbonate, polyarylate, cycloolefin or polyimide, and more preferably contains polycarbonate or polyimide.

The method for producing a multilayer body of the present invention includes attaching the adhesive sheet for bonding of the present invention to a resin molded body.
As a method for bonding the resin molded body and the pressure-sensitive adhesive sheet, a known method can be used. For example, in addition to pasting by hand as it is, the roll laminator method, the water filling method, and the like can be mentioned.

<Use>
The adhesive sheet or multilayer body of the present invention can be used for image display devices such as mobile phone terminals, smartphones, portable electronic play equipment, personal digital assistants, tablet devices, mobile personal computers, wearable terminals, liquid crystal televisions, liquid crystal monitors, desktop personal computers, car navigation systems. , Can be used as a constituent material for various elements such as stationary display devices such as automobile instruments.
In particular, it can be suitably used as a transparent conductive film of the liquid crystal member, a substrate material or a protective material of various elements.
The pressure-sensitive adhesive sheet or multilayer body of the present invention can also be processed by various processing methods. For example, in addition to the method of heating and pressurizing using a mold, a compressed air molding method, a vacuum forming method, a roll homing method, and the like can be exemplified as molding methods. By processing the adhesive sheet or multilayer body of the present invention, it can be used for an element having a curved surface.

In addition to the above, the present invention can refer to the descriptions of International Publication No. 2016/158827, JP-A-2017-200775, and JP-A-2015-147738 without departing from the spirit of the present invention. Is incorporated herein by reference.

The present invention will be described in more detail with reference to examples below. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

[Base material]
<Raw materials>
-Aromatic polycarbonate resin obtained by an interfacial polymerization method using bisphenol AP as a starting material (FPC-0220, manufactured by Mitsubishi Gas Chemical Company, Inc., viscosity average molecular weight 20,200)
-Aromatic polycarbonate resin obtained by an interfacial polymerization method using bisphenol A as a starting material (H-4000F, manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight 16,000)
-Aromatic polycarbonate resin (H-7000F, manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight 14,000) obtained by an interfacial polymerization method using bisphenol A as a starting material.
-Aromatic polycarbonate resin obtained by an interfacial polymerization method using bisphenol A as a starting material (S-3000F, manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight 21,000)

-Aromatic polyarylate using bisphenol A as a starting material (U-powder L type, manufactured by Unitica, dicarboxylic acid component: terephthalic acid / isophthalic acid = 50/50 mol%, bisphenol component: bisphenol A = 100 mol%, weight Average molecular weight 40,800)

-Bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, phosphorus-based antioxidant, ADEKA, ADEKA STAB PEP-36
3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} 1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] Undecane, phosphorus-based antioxidant, manufactured by ADEKA, ADEKA STAB AO-80

<Manufacturing of base sheet 1 and 2>
Weigh and add PEP-36 (0.005 parts by mass) and AO-80 (0.03 parts by mass) to FPC-0220 (45 parts by mass) and H-4000F (55 parts by mass), and use a tumbler for 15 minutes. After mixing, the mixture was melt-kneaded at a cylinder temperature of 320 ° C. by a twin-screw extruder with a vent (manufactured by Japan Steel Works, Ltd., TEX30α), and pellets were obtained by strand cutting.
Discharge of the pellets obtained above using a T-die melt extruder consisting of a twin-screw extruder with a barrel diameter of 32 mm and a screw L / D = 31.5 (manufactured by Japan Steel Works, Ltd., TEX30α). Extruded into a molten state under the conditions of 10 kg / h and screw rotation speed of 63 rpm, crimped with a first roll (mirror surface rubber roll, temperature 50 ° C.) and a second roll (rigid body mirror surface roll, temperature 130 ° C.), cooled and solidified, and a sheet. Was produced. The cylinder / die head temperature was 300 ° C. At that time, by adjusting the discharge amount and the roll take-up speed, a sheet having a thickness of 50 μm (base material sheet 1) and a sheet having a thickness of 100 μm (base material sheet 2) were obtained, respectively.

<Manufacturing of base sheet 3>
In the production of the base sheet 1, instead of FPC-0220 (45 parts by mass) and H-4000F (55 parts by mass), U-powder L type (50 parts by mass) and H-7000F (50 parts by mass) A sheet having a thickness of 50 μm (base sheet 3) was produced in the same manner as in the production of the base sheet 1 except that the thickness was changed to.

<Manufacturing of base sheet 4>
In the production of the base sheet 1, the base sheet 1 was changed to S-3000F (100 parts by mass) instead of FPC-0220 (45 parts by mass) and H-4000F (55 parts by mass). A sheet having a thickness of 50 μm (base sheet 4) was produced in the same manner as in the production.

<Measurement of glass transition temperature (Tg) of substrate>
The glass transition temperature (Tg) of the base material was raised and lowered in two cycles according to the following DSC measurement conditions, and the glass transition temperature at the time of raising the temperature in the second cycle was measured.
The intersection of the straight line extending the baseline on the low temperature side to the high temperature side and the tangent line of the inflection point is the starting glass transition temperature, and the intersection of the straight line extending the baseline on the high temperature side to the low temperature side and the tangent line of the inflection point is The end glass transition temperature was defined, and the intermediate point between the start glass transition temperature and the end glass transition temperature was defined as the glass transition temperature (Tg). The measurement start temperature was 30 ° C., the temperature rise rate was 10 ° C./min, the ultimate temperature was 250 ° C., and the temperature decrease rate was 20 ° C./min.
As a measuring device, a differential scanning calorimeter (DSC, manufactured by Hitachi High-Tech Science Corporation, "DSC7020") was used.

<Measurement of substrate retardation (Re)>
Using an ellipsometer, the maximum direction giving the refractive index of the refractive indices n _x in the plane direction of the substrate _sheet, and, measuring the refractive index n _y in the direction perpendicular to the direction of n _x in the plane direction did. These _n x, retardation from _{n y} (Re) (Unit: nm) was calculated. Five base sheet sheets were cut out to a size of 50 × 50 mm, and Re was measured for each. The average value of the obtained Re was used as the retardation (Re) of the base material.
<< Measurement conditions >>
Spectroscopic method: Double monochrome method Measurement wavelength: 550 nm
Incident angle: 90 °
Bandwidth: 0.5mm
Response: 2 sec
Start and end tilt angles of the anisotropy analysis stage: -50 °, 50 °
Measurement interval: 5 °
As the ellipsometer, "M-220" manufactured by JASCO Corporation was used.

<Measurement of haze>
Using a haze meter, the haze (%) of the substrate was measured under the condition of a D65 light source 10 ° field of view in accordance with JIS-K-7361 and JIS-K-7136.
As the haze meter, "HM-150" (trade name) manufactured by Murakami Color Technology Research Institute was used.

[Preparation of primer paint]
90 parts by mass of hexafunctional urethane acrylate (manufactured by Negami Kogyo Co., Ltd., trade name UN-3320HC), 10 parts by mass of bifunctional acrylate (manufactured by Nippon Catalyst, trade name VEEA), and photopolymerization initiator Irgacure-184 (BASF). (Manufactured by the company, currently sold by IGM Resins BV as an alternative) 5 parts by mass are mixed, and the solid content is 30% by mass with propylene glycol monomethyl ether as a solvent. It was prepared and a primer paint was obtained.

[Preparation of Silicone Adhesive Paint 1 (Silicone 1)]
0.5 part by mass of a platinum catalyst for curing (trade name, CAT-PL-50T manufactured by Shin-Etsu Chemical Co., Ltd.) is added to 100 parts by mass of a silicone compound (manufactured by Shin-Etsu Chemical Co., Ltd., trade name KR-3704). Then, the mixture was sufficiently mixed and diluted with solvent toluene so that the solid content was 40% by mass to obtain Silicone Adhesive Paint 1.

[Preparation of Urethane Adhesive Paint 1 (Urethane 1)]
To 100 parts by mass of the main agent (manufactured by Toyochem Co., Ltd., trade name Siavine SH-101), 4 parts by mass of a curing agent (manufactured by Toyochem Co., Ltd., trade name T-501B) was added, and the mixture was sufficiently mixed to prepare a urethane adhesive solution paint. I got 1.

[Preparation of Urethane Adhesive Paint 2 (Urethane 2)]
Add 3 parts by mass of a curing agent (manufactured by Toyochem, trade name T-501B) to 100 parts by mass of the main agent (manufactured by Toyochem, trade name Siavine SH-205), mix well, and mix well to make a urethane adhesive solution paint. I got 2.

[Preparation of Acrylic Adhesive Paint 1 (Acrylic 1)]
Add 1.5 parts by mass of a curing agent (DIC, trade name D-100K) to 100 parts by mass of the main agent (DIC, trade name Fine Tuck CT-3088), mix well, and adhere to acrylic. Agent paint 1 was obtained.

[Attachment film]
-Polycarbonate (PC) film A 100 μm mirror film made of bisphenol A type polycarbonate (FS-2000, manufactured by MGC Fill Sheet).
-Polyimide (PI) film Film manufactured in the following production example <Manufacturing of PI film>
2,2-Bis [4- (4) in a 5-necked glass round-bottom flask with a stainless half-moon agitator, a nitrogen inlet tube, a Dean Stark with a cooling tube, a thermometer, and a glass end cap. -Aminophenoxy) phenyl] Hexafluoropropane (HFBAPP) 29.034 g (0.056 mol), X-22-9409 18.76 g (0.014 mol), γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) 50 g As a catalyst, 0.039 g of triethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) and 3.54 g of triethylamine (manufactured by Kanto Chemical Co., Inc.) were stirred at 200 rpm in a nitrogen atmosphere to obtain a solution. In this solution, 15.692 g (0.070 mol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride (HPMDA) and 13.5 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) are collectively added. After the addition, the mixture was heated with a mantle heater and the temperature inside the reaction system was raised to 200 ° C. over about 20 minutes. The components to be distilled off were collected, and the temperature inside the reaction system was maintained at 200 ° C. for 3 hours. After adding 78.76 g of N, N-dimethylacetamide (manufactured by Mitsubishi Gas Chemical Company, Inc.), the mixture was stirred at around 100 ° C. for about 1 hour to obtain a uniform polyimide varnish having a solid content concentration of 30% by mass.
Subsequently, the obtained polyimide varnish was applied onto a PET substrate, held at 100 ° C. for 30 minutes, and the solvent was volatilized to obtain a colorless and transparent primary dry film having self-supporting properties. Further, the film was fixed to a stainless steel frame and dried at 230 ° C. in a nitrogen atmosphere for 2 hours to remove the solvent, and a PI film having a thickness of 40 μm was obtained.

[Example 1]
The primer coating film 1 was applied to the substrate sheet 1 obtained by the above method so that the dry coating film had a thickness of 3 μm, and dried at 100 ° C. for 2 minutes in a hot air circulation dryer. Further, an ultraviolet curing device was used to irradiate ultraviolet rays so that the integrated light intensity was 200 mJ / cm ² , to obtain a primer-treated sheet in which a primer layer was formed on the surface of the substrate.
Next, the silicone adhesive coating material 1 is coated on the surface of the primer-treated sheet on the primer layer side using a bar coater so that the thickness of the dry coating film is 40 μm, and the temperature is 120 ° C. with a hot air circulation dryer. Dry for 1 minute to form an adhesive layer.
In this way, the adhesive sheet of Example 1 was obtained.

<Peeling force>
The adhesive sheet obtained above is laminated on the adhesive layer side to the PC film to which it is attached using a film laminator (manufactured by MCK, MP-630), and a tensile tester (manufactured by Shimadzu Corporation, Shimadzu Corporation) is used. An autograph AGS-X) was used to perform a peel test (tensile test) for peeling in the 180 ° direction under the condition of 152 mm / min according to JIS Z0237, and the peeling force (unit: N / 25 mm) was measured.
As a test method, the peeling force of the adhesive layer on the polycarbonate (PC) film was evaluated by a 180 ° peeling test with reference to the "adhesive tape / adhesive sheet test method" specified in JIS Z0237. That is, according to the JIS Z0237 standard, the peeling force of the adhesive tape against a predetermined test plate is measured, but in Example 1 and the like, the peeling force is measured by sticking to a base material. As described above, only the type of the test plate was evaluated for the peeling force by a method different from JIS Z023.

<Paste test>
An adhesive sheet cut to A4 size was laminated on each film to be attached with a film laminator (MP-630 manufactured by MCK), and the appearance of the multilayer body after lamination was confirmed. The evaluation was carried out by 10 people, and the evaluation results selected by a larger number were adopted.
<< Laminating conditions >>
・ Laminating speed: 1.8m / min ・ Left and right nip pressure: 0.3MPa
A: It was possible to laminate without affecting the appearance.
B: Other than the above A, for example, an appearance defect occurred during laminating.

<Removability>
The adhesive sheet obtained above is laminated on each film to be attached with a film laminator (MP-630, manufactured by MCK), cut into a size of 150 mm × 150 mm, and cut at 23 ° C. and 50%. After allowing to stand for 24 hours under the condition of relative humidity (RH), the appearance of the film to which the adhesive sheet was peeled off was confirmed. The evaluation was carried out by 10 people, and the evaluation results selected by a larger number were adopted.
A: It was possible to peel off without affecting the appearance.
B: The appearance was slightly affected, but it was peelable.
C: Other than the above A and B, for example, the base material was deformed at the time of peeling, and re-peeling became impossible.

<Heat resistance test>
Adhesive sheets of A4 size examples and comparative examples are laminated on the destination PI film with a film laminator (MP-630, manufactured by MCK), cut into a size of 150 mm x 150 mm, and ovened. The film was placed in (DKN402 manufactured by Yamato Scientific Co., Ltd.) and allowed to stand at 140 ° C. for 3 hours. After taking out, the warp was observed when the film was allowed to stand in a room at 23 ° C. for 30 minutes. To judge the amount of warpage, place the film on a horizontal table so that the film to which the film is attached is convex downward, and set the amount of warpage at the four corners of the film from the horizontal surface of the table on which the film to be applied is placed. The average value of the amount of warpage at the four corners was calculated. The measurement was performed 5 times and calculated as an average value of 5 times.
A: The average value of the amount of warpage is less than 1 mm B: The average value of the amount of warpage is 1 mm or more

[Example 2]
An adhesive sheet of Example 2 was obtained in the same manner as in Example 1 except that the base sheet 1 was changed to the base sheet 2 in Example 1.

[Example 3]
An adhesive sheet of Example 3 was obtained in the same manner as in Example 1 except that the silicone adhesive coating material 1 was changed to the urethane adhesive coating material 1 in Example 1.

[Example 4]
An adhesive sheet of Example 4 was obtained in the same manner as in Example 1 except that the silicone adhesive coating material 1 was changed to the acrylic adhesive coating material 1 in Example 1.

[Example 5]
An adhesive sheet of Example 5 was obtained in the same manner as in Example 1 except that the base sheet 1 was changed to the base sheet 3 in Example 1.

[Example 6]
An adhesive sheet of Example 6 was obtained in the same manner as in Example 1 except that the silicone adhesive coating material 1 was changed to the urethane adhesive 2 in Example 1.

[Comparative Example 1]
An adhesive sheet of Comparative Example 1 was obtained in the same manner as in Example 1 except that the base material 1 was changed to the base material 4 in Example 1.

10 Adhesive sheet 12 Adhesive layer 16 Primer layer 20 Base material

Claims (18)

1. With a base material containing polycarbonate,
   Including an adhesive layer provided on the substrate,
   A bonding adhesive sheet having a glass transition temperature of 160 ° C. or higher as measured by differential scanning calorimetry of the base material.
2. The polycarbonate contained in the base material contains 100 to 10% by mass of bisphenol AP type polycarbonate and 0 to 90% by mass of bisphenol A type polycarbonate, except that the total of bisphenol AP type polycarbonate and bisphenol A type polycarbonate is 100% by mass. The adhesive sheet for bonding according to claim 1, which does not exceed.
3. The adhesive sheet for bonding according to claim 1 or 2, wherein the base material contains 10 to 90 parts by mass of polyarylate in 100 parts by mass of the resin component contained in the base material.
4. The adhesive sheet for bonding according to any one of claims 1 to 3, wherein the glass transition temperature measured by the differential scanning calorimetry of the base material is 200 ° C. or less.
5. The adhesive sheet for bonding according to any one of claims 1 to 4, wherein the adhesive layer contains an acrylic adhesive.
6. The adhesive sheet for bonding according to any one of claims 1 to 5, wherein the adhesive layer contains a silicone adhesive.
7. The adhesive sheet for bonding according to any one of claims 1 to 6, wherein the adhesive layer contains a urethane adhesive.
8. The adhesive sheet for bonding according to any one of claims 1 to 7, wherein Re, which is an in-plane retardation of the base material, is 100 nm or less.
9. The adhesive sheet for bonding according to any one of claims 1 to 8, wherein the haze of the base material is 0% or more and 1.5% or less.
10. The adhesive sheet for bonding according to any one of claims 1 to 9, wherein the thickness of the base material is 30 μm or more and 200 μm or less.
11. The adhesive sheet for bonding according to any one of claims 1 to 10, wherein the thickness of the adhesive layer is 10 μm or more and 70 μm or less.
12. In a peeling test in which the sheet is laminated on a polycarbonate mirror film on the adhesive layer side and peeled off in a 180 ° direction in accordance with JIS Z0237 under the condition of 152 mm / min, 0.001 to 3 N / 25 mm. The adhesive sheet for bonding according to any one of claims 1 to 11, which shows the peeling force of the above.
13. The adhesive sheet for bonding according to any one of claims 1 to 12, which has a primer layer between the base material and the adhesive layer.
14. A multilayer body in which the adhesive sheet for bonding according to any one of claims 1 to 13 is adhered to at least a part of the surface of the resin molded product on the adhesive layer side.
15. The multilayer body according to claim 14, wherein the resin molded body is a resin sheet.
16. The multilayer body according to claim 14 or 15, wherein the resin molded body contains polycarbonate.
17. The multilayer body according to claim 14 or 15, wherein the resin molded body contains polyimide.
18. A method for producing a multilayer body, which comprises attaching the adhesive sheet for bonding according to any one of claims 1 to 13 to a resin molded body.

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