JP2010187163A - Diaphragm for electric acoustic converter and laminated film for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diaphragm for an electric acoustic converter, which has acoustic characteristics required for a loudspeaker diaphragm of a compact electronic device, heat resistance, durability and light resistance; and to provide a laminated film for the diaphragm. <P>SOLUTION: The laminated film is composed of at least one or more layers of a resin layer (X) including a polybiphenyl ether sulphone resin (A) and a resin layer (Y) including a polyarylate resin (B), and the diaphragm for the electric acoustic converter is formed with the laminated film. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a diaphragm for an electroacoustic transducer used for various acoustic devices. More specifically, the diaphragm is suitable as a speaker diaphragm, and has excellent light resistance in addition to moldability and durability at high output. The present invention relates to a diaphragm for an electroacoustic transducer and a laminated film for the diaphragm.

  With the spread of small electronic devices (for example, mobile phones, PDAs, notebook computers, DVDs, liquid crystal TVs, digital cameras, portable music devices, etc.), small speakers (usually called micro speakers) used in these electronic devices. In addition, demand for small electroacoustic transducers such as microphones and earphones, as well as small receivers, is increasing greatly.

  The speaker diaphragm is low in density to maintain the sound radiation sound pressure level, high in rigidity to suppress distortion and maintain a large allowable input, and has a specific elastic modulus to widen the reproduction frequency band. Therefore, acoustic characteristics such as a large internal loss are required to suppress the divided vibration of the diaphragm and to flatten the frequency characteristics.

  When using the speaker diaphragm in the vicinity of the voice coil that is the drive source or in-vehicle speakers, the diaphragm is exposed to high temperatures for a long time. It becomes.

  On the other hand, in recent years, with the background of mobile and ubiquitous society or the digitization of music sources, various types of small electronic devices have been improved in function and performance. In the speakers used for these, for example, the input / output resistance level required for a speaker diaphragm of a mobile phone is usually about 0.3 W for a general-purpose model, and 0.5 to 0 for a high-output model. .6W or higher (current upper limit is about 1.2W). At present, there are many models of about 0.6 to 0.8 W, and the ratio of models exceeding 1.0 W is low. Here, the speaker diaphragm needs to be durable enough to withstand the input / output resistance level required for the speaker diaphragm of the mobile phone.

  For example, Patent Documents 1 to 3 disclose speaker diaphragms in which a film made of an aromatic polysulfone resin, specifically, a polyethersulfone resin is formed. In these patent documents, it is described that the use of a film made of a polyethersulfone resin is excellent in speaker moldability, heat resistance, acoustic characteristics, and the like.

  Further, for example, Patent Document 4 discloses a diaphragm in which a sheet made of a material made of polyarylate resin is formed into a film by a solution casting method. The invention described in this patent document increases the internal loss by providing flexibility while maintaining heat resistance with a diaphragm material made of polyarylate, expands the low-frequency reproduction band, and reduces unnecessary resonance of the diaphragm. Suppresses and reduces the peak and dip on the sound pressure frequency characteristic, and realizes a stable frequency characteristic. The diaphragm made of a sheet formed by the solution casting method suppresses material thickness variation and reduces speaker characteristics. Can be reduced.

In addition, biaxially stretched thermosetting films such as polyethylene naphthalate resin (PEN) film and polyphenylene sulfide resin (PPS) film are used as speaker diaphragms having excellent durability at high output. However, since these films are crystalline and have too high rigidity, the minimum resonance frequency (f ₀ : F _zero ) is high, and the acoustic characteristics are inadequate, such as poor low-frequency sound reproduction. (Press molding, vacuum molding, etc.) and a molding cycle are inferior to a film made of an amorphous resin (polyetherimide, etc.) having a high glass transition temperature (Tg).

For example, Patent Document 5 proposes a diaphragm for an electroacoustic transducer formed by molding a film containing a polybiphenyl sulfone resin having a specific structure and a crystalline resin as main components. According to the diaphragm, by using a film made of a specific resin and having a tensile modulus of 1000 MPa or more and less than 2500 MPa, a film having a thickness of 20 to 40 μm excellent in durability at high output is used. However, it is described that the lowest resonance frequency (f ₀ : F _zero ) is sufficiently low, and the reproducibility in the low sound range can be improved.

JP-A-60-139099 JP 59-63897 A JP 2002-291092 A JP 2006-20188 A JP 2008-131239 A

  In the speaker diaphragms described in Patent Documents 1 to 3, there is a problem that durability at high output is insufficient, and cracks and breakage of the diaphragm are likely to occur.

  Further, according to the diaphragm described in Patent Document 4, durability and stable frequency characteristics are realized. However, in Patent Document 4, the structure of the aromatic polysulfone resin, in particular, a resin having a specific repeating unit is used. There is no description or examination on the input / output resistance and durability, and the light resistance of the speaker diaphragm formed with the laminated film.

  Furthermore, in the diaphragm described in Patent Document 5, durability at a high output and a low sound range are obtained by using a film containing a polybiphenyl sulfone resin having a specific structure and a crystalline resin as main components. However, it was not always satisfactory in terms of light resistance.

  Accordingly, an object of the present invention is to provide a diaphragm for an electroacoustic transducer having acoustic characteristics, heat resistance, durability, and light resistance necessary for a speaker diaphragm of a small electronic device, and a laminated film for the diaphragm. There is.

  As a result of intensive studies to solve the above problems, the present inventors have found that a resin layer (X) containing a polybiphenyl ether sulfone resin (A) and a resin layer (Y) containing a polyarylate resin (B) )) Can be solved by an electroacoustic transducer diaphragm formed by molding a laminated film in which at least one layer is laminated, and the present invention has been completed.

  That is, according to the first aspect of the present invention, the resin layer (X) containing the polybiphenyl ether sulfone resin (A) and the resin layer (Y) containing the polyarylate resin (B) are each at least one layer or more. An electroacoustic transducer diaphragm characterized by forming a laminated film.

  In the first invention, the resin layer (Y) is preferably provided in the outermost layer. By adopting such a layer structure, the laminated film exhibits excellent light resistance, and also has high rigidity and handling during speaker production is improved.

  In the first invention, the thickness ratio of the resin layer (Y) to the resin layer (X) is preferably 25 to 50%. By adjusting the thickness ratio of the resin layer (Y) in this way, the rigidity of the laminated film is increased and handling during speaker manufacture is improved.

（式中、Ｒ_１〜Ｒ_４は、−Ｏ−、−ＳＯ_２−、−Ｓ−、Ｃ＝Ｏのいずれかであり、ただし、Ｒ_１〜Ｒ_４のうちの少なくとも１つは−ＳＯ_２−であって、且つ、Ｒ_１〜Ｒ_４のうちの少なくとも１つは−Ｏ−である。Ａｒ_１、Ａｒ_２及びＡｒ_３は、６〜２４の炭素原子を含有するアリーレン基であり、好ましくは、フェニレン又はビフェニレンである。ａ及びｂは０又は１のいずれかである。） In the first invention, the resin layer (X) contains a polybiphenyl ether sulfone resin (C) having a repeating unit of the following structural formula (1) and a crystalline resin (D) as main components. Preferably it consists of. Use of the resin composition increases the rigidity of the laminated film and improves handling during speaker production.

(In the formula, R _{1 to} R ₄ are any of —O—, —SO ₂ —, —S—, and C═O, provided that at least one of R _{1 to} R ₄ is —SO _2. And at least one of R _{1 to} R ₄ is —O—, Ar ₁ , Ar ₂ and Ar ₃ are arylene groups containing 6 to 24 carbon atoms, preferably Is phenylene or biphenylene, a and b are either 0 or 1.)

  In the first invention, the mixing mass ratio of the polybiphenyl ether sulfone resin (C) and the crystalline resin (D) is preferably (C) / (D) = 95 to 55/5 to 45.

  In the first invention, the polybiphenyl ether sulfone resin (C) preferably has a glass transition temperature of 180 to 250 ° C.

In the first invention, the polybiphenyl ether sulfone resin (C) is preferably a resin having a repeating unit of the following structural formula (2).

  In the first invention, the crystalline resin (D) is preferably a polyaryl ketone resin.

In the first invention, the polyaryl ketone resin is preferably a resin having a repeating unit of the following structural formula (3).

In the first invention, the polyarylate resin (B) is preferably a resin having a repeating unit of the following structural formula (4).

  In the first aspect of the present invention, the maximum diameter of the diaphragm is preferably 25 mm or less.

  In the first aspect of the present invention, the diaphragm may be a speaker diaphragm.

  The second aspect of the present invention is a laminated film for a diaphragm that is used in the first aspect of the present invention and has a thickness of 40 μm or less. The film used in the first aspect of the present invention can be suitably used as a diaphragm because the rigidity of the laminated film is increased and handling during speaker production is improved even when the thickness is 40 μm or less.

  According to the present invention, the diaphragm for an electroacoustic transducer, which is particularly suitable as a speaker diaphragm used outdoors in a small electronic device such as a mobile phone, and excellent in acoustic characteristics, heat resistance, durability, and light resistance, and A film for the diaphragm can be provided.

  The present invention will be described in detail below.

[Electroacoustic transducer diaphragm]
The electroacoustic transducer diaphragm of the present invention includes at least a resin layer (X) containing a polybiphenyl ether sulfone resin (A) and a resin layer (Y) containing a polyarylate resin (B), respectively. If it is formed by molding a laminated film laminated one or more layers, there is no particular limitation, by molding a laminated film having a resin layer (X) and (Y) made of a specific resin, It can be set as the diaphragm for electroacoustic transducers excellent in acoustic characteristics, heat resistance, durability, and light resistance.

[Laminated film]
(Laminated structure)
The laminated structure of the resin layers (X) and (Y) is not particularly limited as long as the resin layer (X) and the resin layer (Y) are laminated one or more layers. And a two-layer structure composed of resin layer (X) / resin layer (Y) and a three-layer structure composed of resin layer (Y) / resin layer (X) / resin layer (Y). Among these, a structure in which the resin layer (Y) is laminated on the front and back layers is preferable, and a three-layer structure including the resin layer (Y) / resin layer (X) / resin layer (Y) is particularly preferable. In the case of the three-layer configuration, since the rigidity of the resin layer (Y) is high, the rigidity of the laminated film is increased, and handling at the time of manufacturing the speaker is improved, and excellent light resistance can be exhibited.

(Thickness of laminated film)
Although it does not necessarily restrict | limit as thickness of the laminated | multilayer film used by this invention, As a diaphragm for electroacoustic transducers, it is preferable that it is 5-150 micrometers as a whole, and usually about 8-100 micrometers. Moreover, it is preferable that the thickness ratio of the resin layer (Y) with respect to the resin layer (X) is 25 to 50%. By setting it as the laminated structure provided with such thickness ratio, it becomes possible to exhibit effects, such as the rigidity of a laminated film becoming high and the handling at the time of speaker manufacture improving.

(Thickness accuracy of laminated film)
Moreover, since the thickness accuracy (%) of the laminated film ([(film thickness−average thickness) / (average thickness)] × 100) affects the acoustic characteristics such as the reproduction frequency band and the frequency characteristics, it is within ± 10%. It is preferably within ± 8%, more preferably within ± 5%. It is also important to form a film so that the anisotropy of physical properties in the flow direction (MD direction) from the extruder of the film and its orthogonal direction (TD direction) is minimized.

(Resin layer (X))
The resin constituting the resin layer (X) is not particularly limited as long as it contains the polybiphenyl ether sulfone resin (A). Here, the polybiphenyl ether sulfone resin (A) Is a thermoplastic resin that contains an aromatic nucleus bond, a sulfone bond, an ether bond and a biphenyl bond in its structural unit.

（式中、Ｒ_１〜Ｒ_４は、−Ｏ−、−ＳＯ_２−、−Ｓ−、Ｃ＝Ｏのいずれかであり、ただし、Ｒ_１〜Ｒ_４のうちの少なくとも１つは−ＳＯ_２−であって、且つ、Ｒ_１〜Ｒ_４のうちの少なくとも１つは−Ｏ−である。Ａｒ_１、Ａｒ_２及びＡｒ_３は、６〜２４の炭素原子を含有するアリーレン基であり、好ましくは、フェニレン又はビフェニレンである。ａ及びｂは０又は１のいずれかである。） (Polybiphenyl ether sulfone resin (A))
The polybiphenyl ether sulfone resin (A) is preferably an aromatic polysulfone resin (C) having a repeating unit of the following structural formula (1).

(In the formula, R _{1 to} R ₄ are any of —O—, —SO ₂ —, —S—, and C═O, provided that at least one of R _{1 to} R ₄ is —SO _2. And at least one of R _{1 to} R ₄ is —O—, Ar ₁ , Ar ₂ and Ar ₃ are arylene groups containing 6 to 24 carbon atoms, preferably Is phenylene or biphenylene, a and b are either 0 or 1.)

In the structural formula (1), the arylene groups Ar ₁ , Ar ₂ and Ar ₃ are preferably biphenylene groups such as p-biphenylene. By containing this biphenyl bond as an essential structural unit, it is considered that the durability at the time of high output is excellent. The number of repeating units is an integer of 1 to 100, and usually 20 to 50 are suitably used from the viewpoint of securing mechanical properties. Further, the concentration of the biphenyl or biphenylene group is preferably 50 mol% or more, and more preferably 75 mol% or more in order to improve the properties such as impact resistance of the polymer.

  Among the polybiphenyl ether sulfone resins (C) having the repeating unit of the structural formula (1), the glass transition temperature (Tg) is 150 to 320 ° C., preferably 160 to 300 ° C., particularly 180 to 250 ° C. Some are preferably used. A glass transition temperature (Tg) of 150 ° C. or higher is preferable because it has sufficient heat resistance when used in the vicinity of a voice coil that is a driving source of a speaker or a vehicle-mounted speaker. If it exists, it is preferable because the diaphragm can be molded (press molding, vacuum molding, etc.) at a relatively low temperature.

  In the present invention, in particular, a polybiphenyl sulfone resin having a glass transition temperature (Tg) having a repeating unit of the following structural formula (2) of 220 ° C. is a film forming processability, a diaphragm processability, a heat resistance, It is preferably used in terms of acoustic characteristics and durability at high output. Specifically, it is commercially available from Solvay Advanced Polymers Co., Ltd. under the trade name “Radel R”.

  The production method of the polybiphenyl ether sulfone resin (A) used in the present invention is not particularly limited, and a known method can be adopted. These are described in detail in US Pat. Nos. 3,634,355, 4,008,203, 4,108,837, and 4,175,175. Moreover, you may use commercially available resin as it is. The polybiphenyl ether sulfone resin may be used alone or in combination of two or more.

  The resin layer (X) is preferably a resin composition of a polybiphenyl ether sulfone resin (C) and a crystalline resin (D).

(Crystalline resin resin (D))
Examples of the crystalline resin (D) include polyolefin resins, polyamide resins, polyester resins, syndiotactic polystyrene resins, polyphenylene sulfide resins, polyketone resins, polyaryl ketone resins, thermoplastic polyimide resins, and polyether nitrile resins. These are resins in which the crystal melting peak temperature (Tm) is observed by differential scanning calorimetry, and these may be used alone or in appropriate combination of two or more.

  The crystalline melting peak temperature (Tm) of the crystalline resin (D) is preferably 260 to 380 ° C. When the crystal melting peak temperature is 260 ° C. or higher, the heat resistance of the diaphragm for electroacoustic transducers of the present invention is improved, and for example, heat resistance in the reflow process is imparted. On the other hand, a crystal melting peak temperature of 380 ° C. or lower is preferable because, for example, general-purpose equipment can be used in melt molding of a film and processing at a relatively low temperature (upper temperature 430 ° C.) can be performed.

  Furthermore, it is preferable that the crystal melting peak temperature (Tm) of the crystalline resin (D) and the glass transition temperature (Tg) of the polybiphenyl ether sulfone resin (C) have a relationship of Tg <Tm. In this case, when the diaphragm is processed by hot press molding or the like, the film has a temperature distribution in the temperature range equal to or higher than the glass transition temperature (Tg) of the polybiphenyl ether sulfone resin (A). Even if it occurs, the drawdown of the film can be suppressed, and the stress-strain curve in the processing temperature range is improved. As a result, a diaphragm with good thickness accuracy can be produced.

  As the crystalline resin (D), a polyaryl ketone resin that is close to the miscibility with the polybiphenyl ether sulfone resin (C) and has a molding temperature range and excellent in heat resistance and mechanical properties is preferably used. The polyaryl ketone resin is a thermoplastic resin having an aromatic nucleus bond, an ether bond and a ketone bond in its structural unit. Typical examples thereof include a polyether ketone resin, a polyether ether ketone resin, a polyether ketone ketone resin, and the like. However, in the present invention, the polyether ether ketone resin having a repeating unit of the following structural formula (3) is close to the miscibility (compatibility) with the polybiphenyl ether sulfone resin (C) and the molding processing temperature range is close. It is also excellent in heat resistance and mechanical properties, and is preferably used from the viewpoints of film forming processability, diaphragm processability, heat resistance, acoustic characteristics and durability at high output.

  Specifically, trade names VICTREX PEEK "151G", "381G", "450G" from VICTREX Co., Ltd., trade names VESTAKEEEP "2000G", "3001G" "4000G", Solvay Advanced Polymers Corporation ) Under the trade names KetaSpirePEEK “KT-820NT” and “KT-880NT” and Garuda Chemical Co., Ltd. under the trade names GATONE PEEK “5300”, “5400”, “5600” and the like.

(Mixed mass ratio of resin (C) and (D))
The mixing mass ratio between the polybiphenyl ether sulfone resin (C) and the crystalline resin (D) is preferably (C) / (D) = 95 to 55/5 to 45. Here, when the mixing mass ratio is used, the diaphragm is processed by hot press molding or the like so that the polybiphenyl ether sulfone resin (C), which is usually an amorphous resin, forms a film matrix (sea). When working, the workability and its cycle are good, and adhesion to voice coils and housings with various adhesives (for example, UV curing types such as acrylic and epoxy types, solvent dilution types, etc.) and organic solvents It is preferable because the property is also good. Furthermore, the crystalline resin (D) improves the heat resistance and solvent resistance, and the stress-strain curve in the processing temperature range is also improved when processing the diaphragm by hot press molding or the like. It is preferable because a diaphragm with good thickness accuracy and deep drawability can be manufactured. From these, it is more preferable that the mixing mass ratio of the polybiphenyl ether sulfone resin (C) and the crystalline resin (D) is (C) / (D) = 90-60 / 10-10-40, It is particularly preferable that C) / (D) = 85 to 65/15 to 35.

[Resin layer (Y)]
The resin constituting the resin layer (Y) is not particularly limited as long as it contains the polyarylate resin (B). Here, the polyarylate resin (B) is an aromatic dicarboxylic acid in the structural unit. It is a thermoplastic resin containing acid and phenol.

(Polyarylate resin (B))
As said polylylate resin (B), the polyarylate resin which has a repeating unit of following Structural formula (4) is preferable.

  Among the polyarylate resins of the structural formula (4), the glass transition temperature (Tg) is preferably 210 to 230 ° C.

In the polyarylate resin (B), molecules undergo fleece transition on the resin surface when irradiated with ultraviolet rays, and the following structural formula is obtained.

  The polyarylate resin (B) functions as a protective layer because it has a benzophenone skeleton that absorbs ultraviolet rays after the fleece transition, and the fleece transition does not proceed to the inside, and the resin as a whole has excellent light resistance and ultraviolet shielding properties. It is what you have.

(Other additives)
In addition to the above, other resins can be added to the resin layers (X) and (Y) as necessary.

  Other resins include, but are not limited to, polyurethane resin, polysulfone resin, polyethersulfone resin, polyarylate resin, polycarbonate resin, modified polyphenylene ether resin, polyetherimide resin, thermoplastic polyimide resin, liquid crystal polymer And a thermoplastic elastomer, and a polysulfone resin and a polyetherimide resin are preferably used from the viewpoints of miscibility with the main component resin and film forming processability of the film. These other resins to be mixed may be used alone or in combination of two or more. Furthermore, the film used for the diaphragm for electroacoustic transducers of the present invention includes, in addition to the above-described components, fillers and various additives such as heat stabilizers and ultraviolet absorbers within the scope of the present invention. , Light stabilizers, nucleating agents, colorants, lubricants, flame retardants, and the like may be appropriately blended. Moreover, as addition amount, it is 30 mass% or less, Preferably, it can mix in the range of 20 mass% or less.

(Elastic modulus of laminated film)
Moreover, it is preferable that the tensile elasticity modulus of the film used by this invention is 1000 Mpa or more and less than 2500 Mpa. Here, if the tensile elastic modulus is 1000 MPa or more, it has rigidity (waist) that can be used as a diaphragm for an electroacoustic transducer, while if the tensile elastic modulus is less than 2500 MPa, for example, a microspeaker In the case of a diaphragm, the minimum resonance frequency (f ₀ : F _zero ) is sufficiently low even when a film with a thickness of 20 to 40 μm, which is excellent in handling properties and durability at high output, is used, and low-frequency reproducibility is ensured. This is preferable because the sound quality is improved. For these reasons, in the present invention, it is more preferable that the tensile elastic modulus is 2000 MPa or more and less than 2500 MPa.

[Method for manufacturing diaphragm for electroacoustic transducer]
The method for producing the diaphragm for an electroacoustic transducer of the present invention is not particularly limited, and a laminated film in which the resin layers (X) and (Y) are laminated is used as a diaphragm for an electroacoustic transducer. The method of shape | molding to a shape can be mentioned. For example, if a speaker diaphragm is described as an example, the film is heated in consideration of its glass transition temperature and softening temperature, and processed into a dome shape or a cone shape by press molding or vacuum molding, etc. Can be manufactured. The shape of the diaphragm is not particularly limited, and can be arbitrary, and a circular shape, an elliptical shape, an oval shape, and the like can be selected.

[Production method of laminated film]
Examples of the method for producing the laminated film include melt extrusion molding using a T-die extruder. Specifically, a coextrusion casting method is suitably used with a multilayer die using a plurality of extruders. The molding temperature in the coextrusion casting method using a T die is appropriately adjusted depending on the flow characteristics and film-forming property of the composition used, but is generally about 300 ° C. or higher and 430 ° C. or lower.

  Since the above-mentioned laminated film has a low tensile elastic modulus to some extent, particularly when used for a small diaphragm for an electroacoustic transducer, reproducibility in a low sound range is secured and sound quality is improved. Here, as the size of the diaphragm, those having a maximum diameter of 25 mm or less, preferably 20 mm or less, and a lower limit of usually about 5 mm are suitably used. The maximum diameter is a diameter when the diaphragm is circular, and a long diameter when the diaphragm is elliptical or oval.

Further, a groove having a V-shaped cross section called a so-called tangential edge can be appropriately provided on the diaphragm surface. At this time, by setting the thickness of the laminated film to 40 μm or less, more preferably 20 to 38 μm, the thickness is sufficiently secured, so that the handling property is good, and the minimum resonance frequency (f ₀ : F _zero ) is well balanced. In addition, it is preferable because workability per unit time and processing accuracy (reproducibility of shape) such as press molding are easily improved.

  Furthermore, a film used for diaphragm processing suitability, dust resistance, acoustic characteristic adjustment and design improvement is laminated, and an antistatic agent and various elastomers (for example, urethane type) are further formed on the surface of the molded diaphragm. , Silicone-based, hydrocarbon-based, fluorine-based, etc.), metal deposition, sputtering, or coloring (black, white, etc.) may be appropriately performed. Furthermore, lamination with metals such as aluminum and other films, or combination with non-woven fabrics may be performed as appropriate.

  The electroacoustic transducer diaphragm of the present invention is excellent in durability at high output when used for a speaker diaphragm. For example, in a mobile phone, it is possible to cope with an output withstand level of about 0.6 to 1.0 W applicable to a high output model, as compared to about 0.3 W of a general-purpose model. A laminated film in which at least one resin layer (X) containing the polybiphenyl ether sulfone resin (A) as a main component and at least one resin layer (Y) containing the polyarylate resin (B) are laminated. In addition to the basic acoustic characteristics of a speaker diaphragm, particularly a microspeaker diaphragm, it is excellent in heat resistance and moldability during processing of the diaphragm, and also in light resistance.

[Film for diaphragm]
The laminated film for the diaphragm of the present invention is not particularly limited as long as the laminated film has a thickness of 40 μm or less, and the laminated film has the above-described characteristics. It can be preferably used.

  Although the present invention has been described with reference to the most practical and preferred embodiments at the present time, the invention is limited to the embodiments disclosed herein. Rather, the diaphragm for electroacoustic transducers and the laminated film for the diaphragm can be changed as appropriate without departing from the spirit or idea of the invention that can be read from the claims and the entire specification. It should be understood as encompassed within the scope of the present invention.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. In addition, the various measured value and evaluation about the film displayed in this specification were performed as follows. Here, the flow direction from the extruder of the film is called the vertical direction, and the orthogonal direction is called the horizontal direction.

(1) Tensile elongation at break In the longitudinal direction of the obtained film, strips (width 15 mm x length 50 mm), distance between chucks: 50 mm, tensile test speed: 50 mm / min are tested and conform to JIS C2318. The tensile elongation at break was measured. The results evaluated according to the following criteria are also shown in Table 1.
(◎): Tensile rupture elongation is 80% or more compared to before the test (◯): Tensile rupture elongation is 50% or more and less than 80% (x): Tensile rupture elongation is less than 50%

(2) Tensile strength The longitudinal direction of the obtained film was tested under the conditions of a strip shape (width 15 mm × length 50 mm), distance between chucks: 50 mm, tensile test speed: 50 mm / min, and conformed to JIS C2318. Then, the tensile strength was measured. The results evaluated according to the following criteria are also shown in Table 1.
(◎): Tensile strength is 80% or more compared to before the test (O): Tensile strength is 50% or more and less than 80% (×): Tensile strength is less than 50%

Example 1
As a resin layer (X) made of polyarylate resin, 85 parts by mass of polyphenylsulfone resin (manufactured by Solvay Advanced Polymers, Radel R-5000, Tg: 220 ° C., amorphous resin), and crystalline resin A laminated film obtained by laminating a resin layer (Y) composed of 15 parts by mass of a polyether ether ketone resin (manufactured by Victrex Co., Ltd., PEEK450G, Tg: 143 ° C., Tm: 334 ° C.), an irradiance: 110 W / m ^2, black panel temperature: 65 ° C., humidity: 50%, irradiation wavelength: 300 to 400 nm, irradiation time: under conditions of 12 hours, a xenon weather meter (manufactured by Suga test Instruments Co. SX75), were subjected to light resistance test. The resin layer (X) and the resin layer (Y) were peeled from the laminated film after the light resistance test, and the tensile break elongation (%) and the tensile strength (MPa) were measured for each resin layer. The results are shown in Table 1.

(Example 2)
Resin layer (X) made of polyarylate resin and resin layer (Y) made of polyphenylsulfone resin (Solvay Advanced Polymers Co., Ltd., Radel R-5000, Tg: 220 ° C., amorphous resin) The laminated film obtained by laminating was subjected to a light resistance test using a xenon weather meter (SX75 manufactured by Suga Test Instruments Co., Ltd.) under the same conditions as in Example 1, and the results evaluated in the same manner as in Example 1 are shown in Table 1.

(Comparative Example 1)
A xenon weather meter (Suga test) was prepared by melting and extruding a polyphenylsulfone resin (Radel R-5000, manufactured by Solvay Advanced Polymers Co., Ltd., Radel R-5000, Tg: 220 ° C., amorphous resin) under the same conditions as in Example 1. Table 1 shows the results of evaluating the light resistance test by SX75).

(Comparative Example 2)
Polyethersulfone resin (Solvay Advanced Polymers Co., Ltd., Radel R-5000, Tg: 220 ° C., amorphous resin) 85 parts by mass and crystalline resin, polyether ether ketone resin (Victrex Co., Ltd.) PEEK450G, Tg: 143 ° C., Tm: 334 ° C.) A film obtained by melt-kneading 15 parts by mass was subjected to a light resistance test using a xenon weather meter (SX75 manufactured by Suga Test Instruments) under the same conditions as in Example 1. The results are shown in Table 1.

(Comparative Example 3)
Polyethersulfone resin (Solvay Advanced Polymers Co., Ltd., Radel R-5000, Tg: 220 ° C., amorphous resin) 45 parts by mass and crystalline resin, polyether ether ketone resin (Victrex Co., Ltd.) PEEK450G, Tg: 143 ° C., Tm: 334 ° C.) A film (25 μm) obtained by melting and kneading 55 parts by mass was subjected to a light resistance test using a xenon weather meter (SX75 manufactured by Suga Test Instruments) under the same conditions as in Example 1. Table 1 shows the results of the evaluation.

  From Table 1, it was confirmed that the laminated films of Examples 1 and 2 had little change in tensile elongation at break and tensile strength even after the light resistance test and had good light resistance. On the other hand, it was confirmed that the films of Comparative Examples 1 to 3 had little change in tensile strength after the light resistance test, but had a large change in tensile elongation at break and insufficient light resistance.

Claims (13)

    A laminated film in which at least one resin layer (X) containing a polybiphenyl ether sulfone resin (A) and at least one resin layer (Y) containing a polyarylate resin (B) are laminated is formed. A diaphragm for an electroacoustic transducer.     The diaphragm for an electroacoustic transducer according to claim 1, wherein the resin layer (Y) is provided on the outermost layer.     The diaphragm for an electroacoustic transducer according to claim 1 or 2, wherein a thickness ratio of the resin layer (Y) to the resin layer (X) is 25 to 50%. The resin layer (X) contains a resin composition mainly composed of a polybiphenyl ether sulfone resin (C) having a repeating unit of the following structural formula (1) and a crystalline resin (D). The diaphragm for electroacoustic transducers in any one of 1-3.

(In the formula, R _{1 to} R ₄ are any of —O—, —SO ₂ —, —S—, and C═O, provided that at least one of R _{1 to} R ₄ is —SO _2. And at least one of R _{1 to} R ₄ is —O—, Ar ₁ , Ar ₂ and Ar ₃ are arylene groups containing 6 to 24 carbon atoms, preferably Is phenylene or biphenylene, a and b are either 0 or 1.)     The diaphragm for an electroacoustic transducer according to claim 4, wherein a mixing mass ratio of the polybiphenyl ether sulfone resin (C) and the crystalline resin (D) is (C) / (D) = 95 to 55/5 to 45. .     The diaphragm for an electroacoustic transducer according to claim 4 or 5, wherein the polybiphenyl ether sulfone resin (C) has a glass transition temperature in the range of 180 to 250 ° C. The diaphragm for an electroacoustic transducer according to any one of claims 4 to 6, wherein the polybiphenyl ether sulfone resin (C) is a resin having a repeating unit of the following structural formula (2).

    The diaphragm for electroacoustic transducers according to any one of claims 4 to 7, wherein the crystalline resin (D) is a polyaryl ketone resin. The diaphragm for an electroacoustic transducer according to claim 8, wherein the polyaryl ketone resin is a resin having a repeating unit represented by the following structural formula (3).

The diaphragm for an electroacoustic transducer according to any one of claims 1 to 9, wherein the polyarylate resin (B) is a resin having a repeating unit of the following structural formula (4).

    The diaphragm for an electroacoustic transducer according to any one of claims 1 to 10, wherein a maximum diameter of the diaphragm is 25 mm or less.     The diaphragm for an electroacoustic transducer according to claim 1, wherein the diaphragm is a speaker diaphragm.     13. The laminated film for a diaphragm according to claim 1, wherein the thickness is 40 μm or less.