JP6645518B2 - Film, diaphragm material for electro-acoustic transducer, diaphragm for electro-acoustic transducer, micro-speaker diaphragm, and method of using film as diaphragm material for electro-acoustic transducer - Google Patents

Description

  The present invention relates to a diaphragm edge material for an electro-acoustic transducer used for various acoustic devices, and more particularly, is suitable as a speaker diaphragm, and has heat resistance, durability at high output, and reproduction from low to high sounds. TECHNICAL FIELD The present invention relates to a diaphragm for an electroacoustic transducer excellent in workability and workability.

  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 have been developed. Demand for small-sized electroacoustic transducers, such as microphones and earphones, has been increasing.

  In general, the speaker diaphragm has low density to maintain the sound radiation sound pressure level, high rigidity to suppress distortion and maintain large allowable input power, and tension for widening the reproduction frequency band. It is required that the elastic modulus is in a specific range and that the internal loss is large in order to suppress the divided vibration of the diaphragm and flatten the frequency characteristics. In addition, when used near the voice coil, which is the drive source of the speaker, or for in-vehicle speakers, the diaphragm is exposed to high temperatures for a long time, so it must have sufficient heat resistance to withstand such usage conditions. Becomes

  On the other hand, in recent years, with the background of the mobile society, the ubiquitous society, and the digitalization of music sources, various small electronic devices have been enhanced in function and performance. Also in the speakers used for these, for example, the input / output withstand level required for the speaker diaphragm of the mobile phone is about 0.3 W for general-purpose models, and 0.5 to 0.6 W for high-output models. (Upper limit at present is about 1.2 W). However, 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.

  To cope with such a problem, Patent Documents 1 and 2 disclose a diaphragm formed by molding an aromatic polyamide resin film having a high tensile modulus (Young's modulus), and the member has a high elastic modulus. Therefore, there is a description that the resonance frequency in the high frequency range is high, and that it is excellent in reproducing high-pitched sounds. However, this member is a wholly aromatic polyamide resin in which both the dicarboxylic acid component and the diamine component have an aromatic ring, and is not suitable for low-temperature regeneration because the elastic modulus is too high.

  Further, Patent Document 3 describes a speaker diaphragm made of an olefin-based elastomer-modified polyamide resin film having a flexural modulus of 0.1 to 1 GPa, and the film has a heat resistance characteristic of a polyamide resin. There is a description that weather resistance and stability can be improved while maintaining the same. However, the film has a low modulus of elasticity and is not suitable for reproducing high-pitched sounds, and has insufficient heat resistance in applications such as in-vehicle speakers used in a high-temperature environment.

  Further, Patent Document 4 discloses a diaphragm made of a low water-absorbing polyamide resin or polyamide copolymer resin film, and the film has an elastic modulus, a loss coefficient (attenuation characteristic), heat resistance, chemical resistance, and the like. There is a description that the water absorption is low and the moldability during processing is excellent. The polyamide 12 having a low amide group concentration and its copolymer used in the present invention have a low melting point and insufficient heat resistance.

JP-A-01-135297 JP-A-03-038200 JP 08-242497 A JP-A-58-204698

  The present invention relates to an edge material that can be used for a diaphragm for an electroacoustic transducer excellent in heat resistance, durability at high output, reproducibility from low to high pitches, and workability, and using the edge material. It is an object of the present invention to provide a diaphragm for an electroacoustic transducer.

  As a result of intensive studies, the present inventors have found that the above problems can be solved by using a polyamide resin having a specific structure, and have accomplished the present invention.

  That is, the first aspect of the present invention provides a polyamide resin (A) comprising a dicarboxylic acid component (a-1) containing terephthalic acid as a main component and a diamine component (a-2) containing an aliphatic diamine as a main component. Is a diaphragm edge material for an electroacoustic transducer, characterized by containing as a main component.

  In the first aspect of the present invention, the diamine component (a-2) preferably contains 1,9-nonanediamine at a ratio of 50% by mass or more and 100% by mass or less.

  In the first aspect of the present invention, the diamine component (a-2) preferably contains 2-methyl-1,8-octanediamine at a ratio of 1% by mass to 50% by mass.

  In the first aspect of the present invention, the composition further contains an amorphous polyamide resin (B), and the content ratio of the polyamide resin (A) to the amorphous polyamide resin (B) is (A) :( B) = 99: 1 to 60: 40% by mass is preferred.

  The diaphragm edge material for an electroacoustic transducer according to the first aspect of the present invention preferably has a crystal melting enthalpy (ΔHm) of 30 J / g or more.

  In the first embodiment of the present invention, the diamine component constituting the amorphous polyamide resin (B) is 4,4′-methylenebis (cyclohexylamine) (PACM) and 4,4′-methylenebis (2- Methylcyclohexylamine) (MACM), or both.

  At least a part of the diaphragm edge material for an electroacoustic transducer according to the first aspect of the present invention may be processed into a dome shape and / or a cone shape.

  The diaphragm edge material for an electro-acoustic transducer according to the first aspect of the present invention includes an acrylic-based adhesive, a rubber-based adhesive, a silicone-based adhesive, and a urethane-based At least one pressure-sensitive adhesive layer selected from pressure-sensitive adhesives may be provided in the intermediate layer.

  The diaphragm edge material for an electroacoustic transducer according to the first aspect of the present invention is preferably made of a film having a tensile modulus of 1000 MPa or more and less than 2500 MPa in accordance with JIS K7127.

  The diaphragm edge material for an electroacoustic transducer according to the first aspect of the present invention is preferably made of a film having a bending strength of 1000 times or more in accordance with JIS P8115.

  The diaphragm edge material for an electroacoustic transducer according to the first aspect of the present invention is preferably made of a film having a tensile elongation at break of 100% or more according to JIS K7127.

  The diaphragm edge material for an electroacoustic transducer according to the first aspect of the present invention is preferably made of a film having a thickness of 1 μm or more and 200 μm or less.

  A second aspect of the present invention is a diaphragm for an electro-acoustic transducer using the electro-acoustic transducer diaphragm edge material according to the first aspect of the present invention.

  A third aspect of the present invention is a micro-speaker diaphragm using the diaphragm edge material for an electroacoustic transducer according to the first aspect of the present invention.

  The fourth embodiment of the present invention relates to a polyamide resin (A) comprising a dicarboxylic acid component (a-1) containing terephthalic acid as a main component and a diamine component (a-2) containing an aliphatic diamine as a main component. This is a method of using a film contained as a main component as a diaphragm edge material for an electroacoustic transducer.

  ADVANTAGE OF THE INVENTION According to this invention, the diaphragm edge for electroacoustic transducers which is excellent in heat resistance, durability at the time of high output, reproducibility from low tone to high tone, and processability, and can be preferably used when used in various audio equipment. A material and a diaphragm for an electroacoustic transducer using the edge material can be provided.

It is a figure showing the structure of micro speaker diaphragm 1 concerning one embodiment of the present invention. It is a figure showing the structure of micro speaker diaphragm 11 concerning other embodiments of the present invention. It is a figure showing the structure of micro speaker diaphragm 21 concerning other embodiments of the present invention. It is a top view of micro speaker diaphragm 1 'concerning other embodiments of the present invention. It is sectional drawing which showed notionally the layer structure of the diaphragm edge material 10 for electroacoustic transducers which is a laminated body which concerns on other embodiment of this invention.

  Hereinafter, the present invention will be described in detail, but the present invention is not limited to the embodiments described below. Unless otherwise specified, the notation “A to B” for numerical values A and B means “not less than A and not more than B”. When a unit is attached only to the numerical value B in such a notation, the unit is also applied to the numerical value A.

  The diaphragm edge material for an electroacoustic transducer of the present invention contains a polyamide resin (A) as a main component, and further contains an amorphous polyamide resin (B) as necessary. Here, the “main component” means that the ratio of the polyamide resin (A) contained in the diaphragm material for the electroacoustic transducer exceeds 50% by mass. It is important that the ratio of the polyamide resin (A) contained in the edge material of the diaphragm for an electroacoustic transducer exceeds 50% by mass, preferably 60% by mass or more, and more preferably 65% by mass or more. More preferably, it is 70% by mass or more.

[Polyamide resin (A)]
The polyamide resin (A) used in the present invention is a semi-aromatic polyamide resin obtained by polymerizing terephthalic acid and an aliphatic diamine as main components.

  It is important that the dicarboxylic acid component (a-1) constituting the polyamide resin (A) contains terephthalic acid as a main component. That is, it is important that more than 50 mol% of the dicarboxylic acid component (a-1) is terephthalic acid, more preferably 60 mol% or more, and even more preferably 80 mol% or more. , 90 mol% or more, and particularly preferably, all (100 mol%) of the dicarboxylic acid component (a-1) is terephthalic acid. When the dicarboxylic acid component (a-1) contains terephthalic acid as a main component, the diaphragm edge material for an electroacoustic transducer of the present invention is excellent in heat resistance, workability, and low water absorption. In addition, examples of the dicarboxylic acid component other than terephthalic acid include a dicarboxylic acid component derived from isophthalic acid, an aliphatic carboxylic acid, and a hydroxycarboxylic acid.

  It is important that the diamine component (a-2) constituting the polyamide resin (A) contains an aliphatic diamine as a main component. That is, it is important that more than 50 mol% of the diamine component (a-2) is an aliphatic diamine, more preferably 60 mol% or more, even more preferably 80 mol% or more. , 90 mol% or more, and particularly preferably, all (100 mol%) of the diamine component (a-2) is an aliphatic diamine. The diaphragm for an electroacoustic transducer of the present invention is excellent in heat resistance, low water absorption, moldability and workability. The component other than the aliphatic diamine contained in the diamine component (a-2) includes an aromatic diamine component such as xylylenediamine.

The aliphatic diamine component is not particularly limited as long as it is a diamine component having an amine group at both ends of an alkyl chain, and specific examples thereof include 1,2-ethylenediamine, 1,3-propylenediamine, and 1,4-ethylenediamine. Butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 2-methyl-1,8-octanediamine, 1,9-nonanediamine, 1, Examples thereof include 10-decanediamine, 1,11-undecanediamine, and 1,12-dodecanediamine.
Among these, it is preferable to contain 1,9-nonanediamine at a ratio of 50% by mass or more and 100% by mass or less, because the balance between heat resistance and low water absorption, moldability, and processability is excellent, and 60% by mass. The content is more preferably at least 95% by mass and more preferably at least 70% by mass and at most 90% by mass.
In addition, from the viewpoint of imparting further moldability and processability, 2-methyl-1,8-octanediamine is preferably contained in a proportion of 1% by mass or more and 50% by mass or less, preferably 5% by mass or more and 40% by mass. It is more preferably contained at the following ratio, and further preferably contained at a ratio of 10 mass% or more and 30 mass% or less.

  The crystal melting temperature of the polyamide resin (A) is preferably from 260 ° C to 340 ° C, more preferably from 270 ° C to 335 ° C, even more preferably from 280 ° C to 330 ° C. . When the crystal melting temperature of the polyamide resin (A) is 260 ° C. or higher, the heat resistance of the diaphragm material for the electroacoustic transducer is improved. For example, heat resistance that can withstand a reflow step having a peak temperature of 260 ° C. can be provided. On the other hand, a crystal melting temperature of 340 ° C. or lower is preferable because, for example, a general-purpose facility can be used at a relatively low temperature in the melt forming of a film used for an electroacoustic transducer diaphragm edge material of the present invention.

[Amorphous polyamide resin (B)]
The diaphragm edge material for an electroacoustic transducer of the present invention can contain an amorphous polyamide resin (B) as required in addition to the polyamide resin (A). By further containing the amorphous polyamide resin (B), moldability can be improved, and when the glass transition temperature of the amorphous polyamide resin (B) is higher than that of the polyamide resin (A), Glass transition temperature can be improved. In the present invention, the amorphous polyamide resin (B) refers to a polyamide resin having a crystal melting enthalpy of less than 5 J / g.

  Examples of the acid component constituting the amorphous polyamide resin (B) include terephthalic acid, isophthalic acid, aromatic dicarboxylic acid components such as phthalic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, Examples include aliphatic dicarboxylic acid components such as suberic acid, azelaic acid, sebacic acid, decandioic acid, dodecandioic acid, and tetradecanedicarboxylic acid, dicarboxylic acid components derived from hydroxycarboxylic acids, and alicyclic dicarboxylic acid components. Can be.

  As the diamine component constituting the amorphous polyamide resin (B), 1,2-ethylenediamine, 1,3-propylenediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 2-methyl-1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecane Diamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, 1,15-pentadecanediamine, 1,16-hexadecanediamine, 1,17-heptadecanediamine, 1,18-octadecanediamine, 1,19- Aliphatic diamine components such as nonadecane diamine and 1,20-eicosane diamine, 4,4 ′ Alicyclic diamine components such as methylenebis (cyclohexylamine) (PACM) and 4,4'-methylenebis (2-methylcyclohexylamine) (MACM), phenylenediamine, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine And aromatic diamine components such as o-xylylenediamine, m-xylylenediamine and p-xylylenediamine.

  The amorphous polyamide resin (B) may contain a lactam component as a copolymer component in addition to the polyamide component comprising the dicarboxylic acid component and the diamine component. Specifically, γ-butyrolactam, ε-caprolactam, ω-enantholactam, ω-caprolactam, ω-laurolactam and the like can be exemplified.

  The amorphous polyamide resin (B) is composed of the above-mentioned components, and is not particularly limited as long as the crystal melting enthalpy is less than 5 J / g, and particularly, 4,4′-methylenebis (cyclohexylamine) (PACM) as a diamine component, and , 4,4′-methylenebis (2-methylcyclohexylamine) (MACM), or both. When the amorphous polyamide resin (B) contains either or both of PACM and MACM as a diamine component, the glass transition temperature of the amorphous polyamide resin (B) can be improved, and thus the polyamide resin can be improved. When mixed with (A), moldability can be imparted without impairing heat resistance.

  When the amorphous polyamide resin (B) is contained, the content ratio of the polyamide resin (A) and the amorphous polyamide resin (B) is in the range of (A) :( B) = 99: 1 to 60: 40% by mass. Is preferably in the range of 98: 2 to 65: 35% by mass, and more preferably in the range of 97: 3 to 70: 30% by mass. When the content ratio of the polyamide resin (A) and the amorphous polyamide resin (B) is within such a range, moldability can be imparted while maintaining the crystallinity and workability of the polyamide resin (A).

  The glass transition temperature (Tg) of the diaphragm material for an electroacoustic transducer is preferably 120 ° C. or higher, more preferably 130 ° C. or higher, and even more preferably 140 ° C. or higher. If the glass transition temperature of the diaphragm material for an electroacoustic transducer is 120 ° C. or higher, moldability can be imparted without impairing heat resistance.

  The crystal melting enthalpy (ΔHm) of the diaphragm edge material for an electroacoustic transducer is preferably 30 J / g or more, more preferably 40 J / g or more, and even more preferably 50 J / g or more. When the crystal melting enthalpy (ΔHm) is at least 40 J / g, a film or a molded product having high crystallinity can be obtained, and furthermore, the heat resistance of the diaphragm for an electroacoustic transducer is excellent.

  The crystal melting temperature of the diaphragm material for the electroacoustic transducer is preferably from 260 ° C to 340 ° C, more preferably from 270 ° C to 335 ° C, and more preferably from 280 ° C to 330 ° C. More preferred. When the crystal melting temperature of the electroacoustic transducer edge material is 260 ° C. or higher, sufficient heat resistance can be imparted. On the other hand, if the crystal melting temperature of the diaphragm material for the electroacoustic transducer is 340 ° C. or lower, the moldability during melt molding is excellent.

  In the present invention, the mixture of the polyamide resin (A) and the amorphous polyamide resin (B) preferably has a single glass transition temperature. A single glass transition temperature means that the mixture has a strain of 0.1%, a frequency of 10 Hz, and a temperature rising rate of 3 ° C./min., A dynamic dispersion measurement of dynamic viscoelasticity (dynamic viscoelasticity measurement by JIS K7198A method). Means that there is one peak of the main variance of the loss tangent (tan δ), in other words, there is one local maximum of the loss tangent (tan δ). Generally, a single glass transition temperature of a polymer blend composition means that the resins to be mixed are in a state of being compatible at a molecular level, and can be recognized as a compatible system. Conversely, if there are two main dispersion peaks of loss tangent (tan δ) even after blending, it can be said that the system is incompatible. Generally, in the case of an immiscible system, exfoliation occurs at an interface when an external force such as tension or bending is applied, which causes deterioration of mechanical properties. Since the polyamide (A) and the amorphous polyamide (B) are compatible, excellent workability and moldability can be realized.

[Diaphragm for electroacoustic transducer]
The diaphragm edge material for an electro-acoustic transducer of the present invention can be applied to any electro-acoustic transducer such as a speaker, a receiver, a microphone, and an earphone, and can be suitably used particularly as a micro-speaker diaphragm for a mobile phone or the like. . The diaphragm edge material for an electroacoustic transducer of the present invention can be obtained by processing a film having the following preferable characteristics by a method described later.

  The film used for the diaphragm edge material for an electroacoustic transducer of the present invention preferably has a tensile modulus in accordance with JIS K7127 of 1000 MPa or more and less than 2500 MPa. When the tensile elastic modulus is 1000 MPa or more, reproducibility in a high-temperature region is ensured, and the rigidity (stiffness) can be sufficiently used as a diaphragm edge material for an electroacoustic transducer. From this viewpoint, the tensile modulus is more preferably 1500 MPa or more, and particularly preferably 1800 MPa or more. On the other hand, if the tensile elastic modulus is less than 2500 MPa, for example, in the case of a diaphragm of a micro speaker, even if a film having a thickness of 20 to 40 μm excellent in handling properties and durability at high output is used, the lowest resonance frequency (f0 : F zero), which is preferable because reproducibility in a low frequency range is ensured and sound quality is improved. From such a viewpoint, the tensile modulus is more preferably 2400 MPa or less, and particularly preferably 2300 MPa or less.

  The film used for the edge material of the diaphragm for an electroacoustic transducer of the present invention preferably has a bending strength of 1000 times or more, and more preferably 1500 times or more, in accordance with JIS P8115. If the bending strength is within the range, the durability at the time of high output is excellent, and the diaphragm is unlikely to crack or break.

  The film used for the edge material of the diaphragm for an electroacoustic transducer of the present invention preferably has a tensile elongation at break of 100% or more, more preferably 200% or more, in accordance with JIS K7127. As long as the tensile elongation at break is within such a range, it is possible to stably process various shapes, for example, shapes requiring deep drawability, without causing troubles such as breakage.

  Furthermore, in addition to the above-mentioned components, the film used for the diaphragm material for the electroacoustic transducer of the present invention includes other resins and fillers, various additives such as heat, within a range not exceeding the gist of the present invention. A stabilizer, an ultraviolet absorber, a light stabilizer, a nucleating agent, a coloring agent, a lubricant, a flame retardant and the like may be appropriately blended.

  As a method of forming a film used for the diaphragm edge material for the electroacoustic transducer of the present invention, a known method, for example, an extrusion casting method using a T-die, a calendar method, or a casting method can be adopted. Although not particularly limited, an extrusion casting method using a T-die is preferably used in terms of film productivity and the like. The molding temperature in the extrusion casting method using a T die is appropriately adjusted depending on the flow characteristics, film forming properties, and the like of the composition to be used, but is generally from 280 ° C to 350 ° C. For melt-kneading, generally used single-screw extruders, twin-screw extruders, kneaders and mixers can be used, and are not particularly limited, but the uniform dispersibility of the mixed resin composition and the obtained film It is more preferable to use a twin-screw extruder, in particular, a co-directional twin-screw extruder from the viewpoint of the stability of the various characteristics described above.

  In the case of the extrusion casting method using a T-die, the obtained film may be rapidly cooled and collected in an amorphous state, or may be heated by a casting roll or crystallized by performing a heat treatment after being collected in an amorphous state. It may be collected in a state. In general, an amorphous film has excellent durability and processability, and a crystallized film has excellent heat resistance and rigidity. Therefore, it is important to use an optimally crystallized film according to the application. is there.

  The thickness of the film used for the electro-acoustic transducer edge material of the present invention is not particularly limited, but the thickness of the electro-acoustic transducer edge material is usually 1 to 200 μm. It is also important that the film is formed so that the anisotropy of the physical properties in the machine direction (MD) and the cross direction (TD) of the film from the extruder is as small as possible.

  The film thus obtained is further processed and used as a diaphragm edge material for an electroacoustic transducer. Although the processing method is not particularly limited, for example, in the case of a speaker diaphragm, the film is heated in consideration of its glass transition temperature and softening temperature, and at least a part is dome-formed by press molding or vacuum molding. It is used after being processed into a shape or cone shape. The shape of the diaphragm in plan view is not particularly limited and is arbitrary, and a circular shape, an elliptical shape, an oval shape, or the like can be selected.

  FIG. 1 is a diagram showing a structure of a microspeaker diaphragm 1 according to an embodiment of the present invention, and is a cross-sectional view of the circular microspeaker diaphragm 1 cut in a plane passing through a center line of the circle. is there. As shown in FIG. 1, the micro speaker diaphragm 1 has a dome-shaped (body) 1 a processed into a dome shape, a concave fitting portion 1 b attached to the voice coil 2, a peripheral portion (edge) 1 c, and the like. The outer peripheral portion has an external attachment portion 1d attached to a frame or the like. FIG. 2 is a diagram showing a structure of a micro speaker diaphragm 11 according to another embodiment of the present invention, and is a diagram corresponding to FIG. As shown in FIG. 2, the micro speaker diaphragm 11 is attached around a dome-shaped high elastic body 12 attached to the voice coil 2, and has a donut-shaped high elastic body mounting portion 11 i in a plan view and a cone shape. And a peripheral portion (edge) 11c on the outer periphery of the cone portion 11j. FIG. 3 is a view showing a structure of a micro speaker diaphragm 21 according to still another embodiment of the present invention, and is a view corresponding to FIG. As shown in FIG. 3, the micro speaker diaphragm 21 includes a dome portion (body) 21 a formed in a dome shape, a concave fitting portion 21 b attached to the voice coil 2, a cone portion 21 j formed in a cone shape, And it has peripheral part (edge) 21c. As exemplified in the micro speaker diaphragm 21, the diaphragm edge material for an electroacoustic transducer of the present invention has a part processed into a dome shape, and another part excluding the part processed into a cone shape. May be. The microspeaker diaphragms 11 and 21 may have the peripheral portions 11c and 21c attached directly to a frame or the like, or may be attached to the frame or the like via another member.

  Since the film used for the edge material of the diaphragm for an electroacoustic transducer of the present invention does not have too high a tensile elasticity, reproducibility in a low sound range is secured, particularly when used for a small edge material for a diaphragm for an electroacoustic transducer. This is preferable because the sound quality is improved. Here, as the size of the diaphragm, one having a maximum diameter of 25 mm or less, preferably 20 mm or less, and a lower limit of usually about 5 mm is suitably used. The maximum diameter is the diameter when the diaphragm is circular, and the long diameter when the diaphragm is elliptical or oval.

  A groove having a V-shaped cross section, which is called a tangential edge, can be appropriately provided on the diaphragm surface. FIG. 4 shows a plan view of a micro speaker diaphragm 1 'according to another embodiment of the present invention. The micro speaker diaphragm 1 'is provided with a tangential edge portion 1g provided with a plurality of tangential edges 1e and a plurality of tangential edges 1f on an outer peripheral portion of a circular dome portion (body) 1a'. Tangential edge portion 1h. In the form having a tangential edge, when the average thickness of the film is preferably 3 to 40 μm, more preferably 5 to 38 μm, the thickness is sufficiently ensured, the handling properties are good, and the time per press molding or the like is good. This is preferable because processability and process accuracy (reproducibility of shape) are easily improved.

  Further, the diaphragm edge material for an electroacoustic transducer of the present invention is a laminate having the diaphragm edge material for an electroacoustic transducer on the front and back layers and at least one adhesive layer having a high damping effect (internal loss) on the intermediate layer. You may. FIG. 5 shows a diaphragm edge member 10 for an electroacoustic transducer, which is a laminate according to an embodiment of the present invention. The electro-acoustic transducer diaphragm edge member 10 which is a laminate has a single-layer electro-acoustic transducer diaphragm edge member 3 as a front and back layer, and one adhesive layer 4 as an intermediate layer. With such a laminated structure, in addition to the heat resistance, rigidity, durability and moldability of the edge material for the electroacoustic transducer of the front and back layers, it is possible to impart excellent damping characteristics of the intermediate layer. . There is no particular limitation on the method of manufacturing the diaphragm edge material for an electroacoustic transducer that is a laminate. For example, by processing a pair of films having the above preferable characteristics to produce a diaphragm edge material for the electroacoustic transducer constituting the surface layer and the back layer, and by bonding these via an adhesive used for the intermediate layer. A method of producing the film, or a method of forming a laminated film by bonding a pair of films having the above-described preferable properties via an adhesive used for an intermediate layer, and processing the laminated film by the above method may be used. In this case, examples of the type of the adhesive used for the intermediate layer include an acrylic adhesive, a rubber-based adhesive, a silicone-based adhesive, a urethane-based adhesive, and the like. It is preferable to use a system-based adhesive. In this case, the thickness of the surface layer and the thickness of the back layer are each preferably 1 μm or more and 30 μm or less, more preferably 2 μm or more and 25 μm or less, and still more preferably 3 μm or more and 20 μm or less. On the other hand, the thickness of the intermediate layer is preferably 3 μm or more and 50 μm or less, more preferably 5 μm or more and 40 μm or less, and even more preferably 10 μm or more and 30 μm or less. With a configuration in which the material type of the intermediate layer and the thickness of each layer are large, it is possible to obtain a diaphragm excellent in damping characteristics while maintaining various mechanical characteristics and molding.

  Furthermore, in order to adjust the processing suitability and dust resistance of the diaphragm, or to adjust the acoustic characteristics and improve the design, etc., the surface of the film or the formed diaphragm used for the diaphragm edge material for the electroacoustic transducer of the present invention is further prevented from being charged. Processing such as coating or laminating agents and various elastomers (eg, urethane, silicone, hydrocarbon, fluorine, etc.), metal deposition, sputtering, or coloring (black, white, etc.) May be appropriately performed. Furthermore, lamination with a metal such as aluminum or another film, or compounding with a nonwoven fabric, etc., may be appropriately performed.

  The diaphragm edge material for an electroacoustic transducer of the present invention has excellent durability at high output when used for a speaker diaphragm. For example, a mobile phone can support an output level of about 0.6 to 1.0 W which can be applied to a high output model, compared to about 0.3 W of a general-purpose model. In addition, the film containing the polyamide resin (A) as a main component is excellent in heat resistance and moldability in processing the diaphragm in addition to the basic acoustic characteristics as a speaker diaphragm, particularly a diaphragm of a micro speaker. ing.

  In general, a "film" is a thin flat product whose thickness is extremely small compared to its length and width, and whose maximum thickness is arbitrarily limited, and which is usually supplied in the form of a roll. (JIS K6900), the term “sheet” generally means a flat product that is thin in definition according to JIS, and whose thickness is small for length and width. However, since the boundary between the sheet and the film is not clear, and it is not necessary to distinguish the two literally in the present invention, even when the present invention refers to a “film”, the term includes a “sheet” and is referred to as a “sheet”. Even in this case, the term “film” is included.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. In addition, various measurements were performed on the raw materials described in this specification and the film used for the edge material of the diaphragm for an electroacoustic transducer of the present invention as follows.

(1) Glass transition temperature, crystal melting temperature, crystal melting enthalpy For various raw materials and the obtained film, the glass transition in the heating process was performed using a differential scanning calorimeter (DSC) measurement at a heating rate of 10 ° C./min according to JIS K7121. Temperature, crystal melting temperature and crystal melting enthalpy were measured.

(2) Tensile modulus The obtained film was measured at a temperature of 23 ° C. in accordance with JIS K7127.

(3) Folding strength The obtained film was measured at a temperature of 23 ° C in accordance with JIS P8115.

(4) Tensile Elongation at Break The obtained film was measured at a temperature of 23 ° C. and a test speed of 200 mm / min in accordance with JIS K7127.

1. Polyamide resin (A)
(A) -1: PA9T / 2-Me8T (manufactured by Kuraray Co., Ltd., trade name: Genestar N1000A, terephthalic acid / 1,9-nonanediamine / 2-methyl-1,8-octanediamine = 50 / 42.5 / 7) (0.5 mol%, crystal melting temperature: 302 ° C., crystal melting enthalpy: 59 J / g, glass transition temperature: 120 ° C.)
(A) -2: PA9T / 2-Me8T (manufactured by Kuraray Co., Ltd., trade name: Genestar N1001D, terephthalic acid / 1,9-nonanediamine / 2-methyl-1,8-octanediamine = 50/25/25 mol%) , Crystal melting temperature: 266 ° C, crystal melting enthalpy: 46 J / g, glass transition temperature: 120 ° C)

2. Amorphous polyamide resin (B)
(B) -1: MACMT / MACMI / 12 (manufactured by EMS, trade name: Glylamid TR60, terephthalic acid / isophthalic acid / MACM / ω-laurolactam = 22/17/37/24 mol%, crystal melting enthalpy: 0 J / g, glass transition temperature: 190 ° C)

(Example 1)
(A) -1 as a polyamide resin (A) was kneaded at 320 ° C. using a Φ25 mm co-directional twin screw extruder, extruded from a T-die, and then quenched with a casting roll at about 100 ° C. A film was prepared. No crystallization treatment was performed. The measurements (1) to (4) were performed on the obtained film. Table 1 shows the results.

(Example 2)
The production and measurement of the film were performed in the same manner as in Example 1 except that the temperature of the casting roll was set to 210 ° C. and the film was collected in a crystallized state. Table 1 shows the results.

(Example 3)
A film was prepared and measured in the same manner as in Example 1 except that (A) -1 and (B) -1 were dry-blended at a mixing mass ratio of 90:10 and used. Table 1 shows the results. No crystallization treatment was performed.

(Example 4)
Example 1 except that (A) -1 and (B) -1 were dry-blended at a mixing mass ratio of 90:10 and used and the film was crystallized at a casting roll temperature of 210 ° C. Preparation and measurement of a film were performed in the same manner as in the above. Table 1 shows the results.

(Example 5)
A film was prepared and measured in the same manner as in Example 1 except that (A) -1 and (B) -1 were dry-blended at a mixing mass ratio of 80:20 and used. Table 1 shows the results. No crystallization treatment was performed.

(Example 6)
A film was prepared and measured in the same manner as in Example 1 except that (A) -1 and (B) -1 were dry-blended at a mixing mass ratio of 70:30 and used. Table 1 shows the results. No crystallization treatment was performed.

(Example 7)
A film was prepared and measured in the same manner as in Example 1 except that (A) -1 and (B) -1 were dry blended at a mixing mass ratio of 60:40 and used. Table 1 shows the results. No crystallization treatment was performed.

(Example 8)
A film was prepared and measured in the same manner as in Example 1 except that (A) -2 was used as a raw material. Table 1 shows the results. No crystallization treatment was performed.

(Comparative Example 1)
A film was prepared and measured in the same manner as in Example 1 except that (A) -1 and (B) -1 were dry-blended at a mixing mass ratio of 50:50 and used. Table 1 shows the results. No crystallization treatment was performed.

(Comparative Example 2)
As a raw material, (N) -1: PES (manufactured by Sumitomo Chemical Co., Ltd., trade name: Sumika Excel 4800G, polyether sulfone, glass transition temperature: 225 ° C.), a kneading temperature of 350 ° C. and a casting roll temperature of A film was prepared and measured in the same manner as in Example 1 except that the temperature was changed to 200 ° C. Table 1 shows the results. No crystallization treatment was performed.

(Comparative Example 3)
(N) -2: PEEK (Vestakeep 3300G, manufactured by Daicel Evonik Co., Ltd., crystal melting temperature: 334 ° C., crystal melting enthalpy: 29 J / g, glass transition temperature: 143 ° C.), and a kneading temperature of 380 The production and measurement of the film were carried out in the same manner as in Example 1 except that the film was collected in a state where the film was crystallized at a temperature of 230 ° C. and a casting roll temperature of 230 ° C. Table 1 shows the results.

(Comparative Example 4)
As a raw material, (N) -3: PPSU (manufactured by Solvay Advanced Polymers Co., Ltd., trade name: Radel R-5000, polyphenylene sulfone, glass transition temperature: 220 ° C.), a kneading temperature of 350 ° C., and a casting roll Preparation and measurement of a film were performed in the same manner as in Example 1 except that the temperature was set to 200 ° C. Table 1 shows the results. No crystallization treatment was performed.

(Comparative Example 5)
Preparation of a film in the same manner as in Example 1 except that (N) -2 and (N) -3 were dry-blended at a mixing mass ratio of 50:50 and the kneading temperature was 380 ° C. as a raw material. And measurements were made. Table 1 shows the results. No crystallization treatment was performed.

(Comparative Example 6)
A film was prepared and measured in the same manner as in Example 1 except that (N) -2 was used as a raw material and the kneading temperature was 380 ° C. Table 1 shows the results. No crystallization treatment was performed.

In Example 1, the film containing the polyamide resin (A) of the present invention as a main component is used in an amorphous state. Since the tensile elastic modulus of the film is in an appropriate range, the film is excellent not only in rigidity (stiffness) and, in addition, excellent in handleability, but also excellent in reproducibility in a low range.
In Example 2, the film containing the polyamide resin (A) of the present invention as a main component was subjected to a heat treatment and used in a crystallized state. Although this film is slightly inferior in durability and workability as compared with an amorphous film, it can be seen that the film maintains properties sufficient for use as a diaphragm and is particularly excellent in rigidity.
In Examples 3 and 5 to 7, a film mainly containing a mixture of the polyamide resin (A) and the amorphous polyamide resin (B) of the present invention is used in an amorphous state. Since the polyamide resin (A) and the amorphous polyamide resin (B) are compatible systems and the glass transition temperature of the amorphous polyamide resin (B) is higher than that of the polyamide resin (A), the film has various properties. It can be seen that the glass transition temperature was improved while maintaining the above.
In Example 4, a film containing a mixture of the polyamide resin (A) of the present invention and the amorphous polyamide resin (B) as a main component was subjected to a heat treatment and used in a crystallized state. Although this film is slightly inferior in durability and workability as compared with an amorphous film, it can be seen that the film maintains properties sufficient for use as a diaphragm and is particularly excellent in rigidity.
In Example 8, a film mainly composed of a raw material having a higher proportion of the copolymer component (2-methyl-1,8-octanediamine) than the raw material (PA9T) used in Example 1 was used in an amorphous state. ing. Although this film has a lower crystal melting enthalpy and a lower crystal melting temperature than the film of Example 1, it has sufficient heat resistance to be used as a diaphragm, and other various properties are equivalent. You can see that there is.
On the other hand, in Comparative Example 1, a film mainly containing a mixture of the polyamide resin (A) and the amorphous polyamide resin (B) of the present invention was used in an amorphous state. Since the ratio of the amorphous polyamide resin (B) in the mixture is too high, the film has a low crystal melting enthalpy, that is, a low crystallinity, and has insufficient heat resistance.
In Comparative Example 2, a film containing PES (polyethersulfone), which is a heat-resistant amorphous resin, as a main component was used. Since the film uses an amorphous resin, it has no melting point and is inferior in heat resistance. Further, not only the tensile elastic modulus is high, and the reproducibility of low sound is inferior, but also the workability, especially the deep drawing formability is not sufficient because the tensile elongation at break is low.
In Comparative Example 3, a film containing PEEK (polyetheretherketone) as a main component was subjected to a heat treatment and used in a crystallized state. The film has a high tensile modulus and is not only inferior in low-pitched sound reproducibility but also has insufficient durability at high output.
In Comparative Example 4, a film mainly containing PPSU (polyphenylene sulfone), which is a heat-resistant amorphous resin, is used. Since the film uses an amorphous resin, it has no melting point and is inferior in heat resistance. Further, the bending resistance is low, and the durability at the time of output resistance is not sufficient.
In Comparative Example 5, a film in which PEEK and PPSU were mixed at 50: 50% by mass was used in an amorphous state. The film has two glass transition temperatures because PEEK and PPSU are incompatible or partially compatible. The ratio of the amorphous resin component is high, and the crystal melting enthalpy is low, that is, the crystallinity is reduced, and the heat resistance is not sufficient.
In Comparative Example 6, a film mainly composed of PEEK was used in an amorphous state. Although the tensile modulus is somewhat high, it is generally in a preferable range, and the overall balance of properties is excellent.

1, 1 'Micro speaker diaphragm 1a, 1a' Dome (body)
1b Recessed part 1c Peripheral part (edge)
1d External sticking part 1e, 1f Tangential edge 1g, 1h Tangential edge part 2 Voice coil 3 Diaphragm edge material for electroacoustic transducer (single layer)
4 pressure-sensitive adhesive layer 10 diaphragm edge material for electroacoustic transducer (laminate)
11 Micro speaker diaphragm 11c Peripheral part (edge)
11i High elastic body attachment part 11j Cone part 12 High elastic body 21 Micro speaker diaphragm 21a Dome part (body)
21b Recessed part 21c Peripheral part (edge)
21j cone

Claims (14)

  A polyamide resin (A) composed of a dicarboxylic acid component (a-1) containing terephthalic acid as a main component and a diamine component (a-2) containing an aliphatic diamine as a main component, as a main component, and A film having a thickness of 1 μm or more and 30 μm or less is disposed on the front and back layers, and at least one adhesive layer selected from an acrylic adhesive, a rubber adhesive, a silicone adhesive, and a urethane adhesive is disposed on the intermediate layer. Film used for diaphragm for electroacoustic transducer.   The film used for a diaphragm for an electroacoustic transducer according to claim 1, wherein the diamine component (a-2) contains 1,9-nonanediamine at a ratio of 50% by mass or more and 100% by mass or less.   3. The electroacoustic according to claim 1, wherein the diamine component (a-2) contains 2-methyl-1,8-octanediamine at a ratio of 1% by mass or more and 50% by mass or less. Film used for transducer diaphragms. The film used for the diaphragm for an electroacoustic transducer according to any one of claims 1 to 3 , wherein the film has a crystal melting enthalpy (ΔHm) of 30 J / g or more. The film further contains an amorphous polyamide resin (B), and the content ratio of the polyamide resin (A) and the amorphous polyamide resin (B) is (A) :( B) = 99: The film used for the diaphragm for an electroacoustic transducer according to any one of claims 1 to 4 , wherein the content is 1 to 60: 40% by mass. The diamine component constituting the amorphous polyamide resin (B) may be any of 4,4′-methylenebis (cyclohexylamine) (PACM) and 4,4′-methylenebis (2-methylcyclohexylamine) (MACM) The film used for the diaphragm for an electro-acoustic transducer according to claim 5 , wherein the film contains both or both.   The film used for the diaphragm for an electroacoustic transducer according to any one of claims 1 to 6, wherein at least a part of the film is processed into a dome shape and / or a cone shape. Tensile modulus than 1000 MPa, less than 2500 MPa, to an electric acoustic converter diaphragm according to claim 1 film.   The film used for the diaphragm for an electroacoustic transducer according to any one of claims 1 to 8, wherein the bending strength according to JIS P8115 is 1,000 times or more.   The film used for the diaphragm for an electroacoustic transducer according to any one of claims 1 to 9, wherein a tensile elongation at break based on JIS K7127 is 100% or more.   A diaphragm edge material for an electroacoustic transducer, comprising the film according to claim 1.   A diaphragm for an electroacoustic transducer using the edge material for a diaphragm for an electroacoustic transducer according to claim 11.   A micro-speaker diaphragm using the diaphragm member for an electroacoustic transducer according to claim 11.   A polyamide resin (A) composed of a dicarboxylic acid component (a-1) containing terephthalic acid as a main component and a diamine component (a-2) containing an aliphatic diamine as a main component, as a main component, and A film having a thickness of 1 μm or more and 30 μm or less is disposed on the front and back layers, and at least one adhesive layer selected from an acrylic adhesive, a rubber adhesive, a silicone adhesive, and a urethane adhesive is disposed on the intermediate layer. A method using a film as a diaphragm edge material for an electroacoustic transducer.

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