JP2008144291A - Fabric having three-dimensional structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fabric having a three-dimensional structure and particularly suitable as a damper for a speaker cone and to provide the damper for the speaker cone which has a little secular change in minimum resonance frequency and excellent durability. <P>SOLUTION: The fabric having the three-dimensional structure is composed of knitted or woven fabrics in two layers of the right side and the back side and connecting yarns connecting the knitted or woven fabrics in the two layers. The fabric includes fibers composed of a polyketone in which ≥95 mol% of repeating units is represented by formula (1). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a three-dimensional fabric, and more particularly to a three-dimensional fabric suitable for a speaker damper.

The damper for the speaker is a component in the speaker of the sound output device, and is a function that is elastically supported by a coil bobbin that transmits vibration to a diaphragm (speaker cone) that radiates sound and a speaker frame. It has the form which expanded corrugation of concentric circle in the shape of a field.
Patent Document 1 proposes a base material for such a damper for a speaker using an aramid fiber. Although the durability is greatly improved as compared with a damper using a cotton cloth, further improvement is required. Has been.

JP 2006-129037 A

  The present invention provides a three-dimensional fabric suitable for a damper for a speaker that meets such a demand.

The inventors of the present invention have reached the present invention as a result of intensive studies to solve the above problems.
That is, the present invention is as follows.
(1) A three-dimensionally structured fabric composed of at least two layers of knitted fabrics on the front and back sides and a connecting yarn for linking the two layers of knitted fabrics, wherein 95 mol% or more of the repeating units are represented by the following formula (1) A three-dimensional fabric characterized by containing a fiber (hereinafter referred to as polyketone fiber).

  According to the present invention, a three-dimensional structure fabric particularly suitable for a damper for a speaker is provided, and a damper for a speaker having a minimum change in the resonance frequency with time and excellent durability is provided.

但し式中、Ｒは、エチレン以外の炭素数１〜３０の有機基であり、例えば、プロピレン、ブチレン、１−フェニルエチレン等の基であり、Ｒの水素原子の一部または全部が、ハロゲン基、エステル基、アミド基、水酸基、エーテル基で置換されていてもよい。もちろん、Ｒは二種以上であってもよく、例えば、プロピレンと１−フェニルエチレンが混在していてもよい。 The present invention will be specifically described below.
The polyketone constituting the polyketone fiber of the present invention is composed of 95 mol% or more, preferably 98 mol% or more, particularly 99.6 mol% or more of the repeating units, composed of units represented by the above formula (1), In the range of less than 5 mol%, a repeating unit other than the above formula (1), for example, one represented by the following formula (2) may be contained.

In the formula, R is an organic group having 1 to 30 carbon atoms other than ethylene, for example, a group such as propylene, butylene, 1-phenylethylene, etc., and a part or all of the hydrogen atoms of R are halogen groups. , An ester group, an amide group, a hydroxyl group, and an ether group may be substituted. Of course, two or more types of R may be used. For example, propylene and 1-phenylethylene may be mixed.

式中のｔ及びＴは、それぞれヘキサフルオロイソプロパノール（セントラル硝子（株）社製）及び該ヘキサフルオロイソプロパノールに溶解したポリケトンの希釈溶液の２５℃での粘度管の流過時間である。Ｃは、上記希釈溶液の濃度であり、ヘキサフルオロイソプロパノール１００ｍｌ中のポリケトンの質量（ｇ）である。
ポリケトンには、必要に応じて、酸化防止剤、ラジカル抑制剤、他のポリマー、艶消し剤、紫外線吸収剤、難燃剤、金属石鹸等の添加剤を含んでいてもよい。 The intrinsic viscosity [η] of the polyketone is preferably 1 dl / g or more, more preferably 2 dl / g or more, particularly preferably 4 dl / g or more, preferably 20 dl / g or less, 15 dl / g or less, and 10 dl / g or less. .
The intrinsic viscosity [η] is a value obtained based on the following definition formula.

In the formula, t and T are the flow times of the viscosity tube at 25 ° C. of hexafluoroisopropanol (manufactured by Central Glass Co., Ltd.) and a dilute solution of polyketone dissolved in the hexafluoroisopropanol, respectively. C is the concentration of the diluted solution and is the mass (g) of polyketone in 100 ml of hexafluoroisopropanol.
The polyketone may contain additives such as antioxidants, radical inhibitors, other polymers, matting agents, ultraviolet absorbers, flame retardants, and metal soaps as necessary.

  Next, as preferable characteristics of the polyketone fiber, the tensile strength is 5 cN / dtex or more, more preferably 10 cN / dtex or more, particularly preferably 15 cN / dtex or more, 30 cN / dtex or less, and the tensile elongation is 3%. Or more, more preferably 3.5% or more, particularly preferably 4% or more, 8% or less, more preferably 7% or less, particularly preferably 6% or less, and the tensile elastic modulus is 100 cN / dtex or more, more Preferably it is 200 cN / dtex or more, Most preferably, it is 300 cN / dtex or more, and is 1000 cN / dtex or less.

The form of the polyketone fiber may be either short fiber or long fiber, and may be uniform or thick in the length direction. The cross-sectional shape of the fiber is round, triangular, L-shaped, T-shaped, Y Type, W type, Yaba type, flat type (thickness of about 1.3-4), W type, I type, boomerang type, wave type, skewer type, eyebrows type, rectangular parallelepiped type and the like. ), Polygonal type such as dogbone type, multi-leaf type, hollow type, and indeterminate type. The preferred single yarn fineness is 0.01 to 10 dtex in the case of spun yarn or multifilament yarn, more preferably 0.1 to 10 dtex, particularly preferably 0.5 to 5 dtex, and 10 to 100,000 dtex in the case of monofilament yarn. It is. Moreover, a preferable total fineness is 10-100,000 dtex, More preferably, it is 30-50000 dtex.
Polyketone fiber yarn forms are spun yarn, multifilament yarn, and monofilament yarn.

In the present invention, such a polyketone fiber is used to form a three-dimensionally structured fabric. The polyketone fiber may constitute at least one or both of the two layers of the front and back layers, or connect the two layers of the knitted fabric. You may use for a connection thread | yarn, and you may comprise all by a polyketone fiber using both.
Fibers other than polyketone fibers may be preferably used within a range of 50% by mass or less, and as a mixed form, 100% polyketone fibers or fibers other than polyketone fibers are mixed in one of the knitted fabrics of the front and back layers, The other side of the knitted fabric of the front and back layers is mixed with 100% fiber other than polyketone fiber or mixed with polyketone fiber, or the connecting thread is mixed with 100% polyketone fiber, 100% fiber other than polyketone fiber or mixed with polyketone fiber. May be.

The mixed fibers include polyester fibers such as polytrimethylene terephthalate, polyethylene terephthalate, and polybutylene terephthalate, polyamide fibers such as nylon 6 and nylon 66, acrylic fibers, wholly aromatic polyester fibers, polyphenylene sulfide fibers, polyimide fibers, and aramid fibers. (Para-type, meta-type), polyvinyl alcohol fiber, poly (p-phenylenebenzobisoxazole) fiber, ultra-high molecular weight polyolefin fiber, and other known fibers may be mentioned. Mixed means, mixed spinning (silospan, silofil) ), Blended fibers, cross-twisting, complex bulk processing (false twist, fluid injection processing, etc.), union knitting (for example, 1 to 5 yarns are alternately mixed in warp and / or weft) Can do.
Furthermore, the fibers constituting the three-dimensionally structured fabric (polyketone fibers or mixed fibers) may be softened or melted by pressurization and / or heating means, and bonded or fused as desired. .
In particular, it is preferable to use polytrimethylene terephthalate, polybutylene terephthalate, polyamide fiber such as nylon 6 or nylon 66 for the connecting yarn because a three-dimensional structure fabric excellent in cushioning properties can be obtained.

The three-dimensional structured fabric in the present invention refers to a three-dimensional structured fabric having a three-dimensional knitted fabric whose front and back two-layer structure is a knitted fabric and a three-dimensional woven fabric which is a woven fabric, and having at least two layers of a knitted fabric. A three-dimensional fabric having three or more layers of knitted fabric may be used.
The three-dimensional knitted fabric can be manufactured by using a double raschel machine having two rows of needle rows, a double circular knitting machine, a double flat knitting machine, or the like.
The three-dimensional woven fabric can be manufactured using a multi-stage opening loom such as a double velvet loom, a jacquard loom, a dobby loom, or a multilayer loom. These are weaving machines that weave while maintaining the gap between the upper and lower fabric layers by opening operation or installing a multistage opening device, and the connecting warp is performed from a separate source from the ground warp, At the point where the upper and lower fabric layers are joined, the yarn feed amount is adjusted and supplied each time. Further, two or more types of connecting yarns may be woven, and at least a pair of connecting yarns may form an acute angle with respect to the front and back tissue surfaces, and a pair of connecting yarns may intersect each other at a predetermined angle. In that case, the yarn feed amount is separately adjusted and supplied.

First, the three-dimensional fabric will be described.
The front and back structures of the three-dimensional fabric may be the same or different structures, and the woven structure is a plain structure or twill structure that exhibits the strongest tissue binding force, and also a satin structure, It may be a guiding tissue.
By using a jacquard loom, a dobby loom, or the like, a complicated woven fabric structure can be imparted to the front and back surfaces, so that it is possible to impart a sophisticated and aesthetic design.
As for the weft insertion method of the loom, a rapier loom, a shuttle loom, a fluid jet loom such as an air jet loom, or the like can be used.
The woven density of the front and back tissue surfaces and the connection density and thickness of the connecting yarn are not particularly limited, but when the apparent density of the three-dimensional fabric is d, d is in the range of 0.02 to 0.30 g / cm ³ . Preferably, it is in the range of 0.05 to 0.20 g / cm ³ . The connection density of the connecting yarn is preferably about 50 to 1000 / 2.54 cm 2. The connection density is the number of connected yarns that circulate around the weft yarn structure points per 2.54 cm square when the three-dimensional fabric is viewed from the plane.
The thickness of the three-dimensional fabric is preferably about 2 to 20 mm, particularly preferably about 3 to 15 mm, and can be arbitrarily set by selecting the positions of the upper and lower opening lines and the spacers.

Next, a three-dimensional knitted fabric will be described as an example.
The two-layer knitted fabric may be further improved in air permeability and water permeability to a knitted fabric having a plurality of openings, such as a mesh knitted fabric and a margitette knitted fabric. The two layers of the knitted fabric on the front and back sides may have the same knitting structure and different structures.
Regarding the knitting density of the connecting yarn, the number of connecting yarns within 5 cm ² is N (pieces / 5 cm ² ), the dtex of the connecting yarn is D (g / 10 × 10 ⁵ cm), and the specific gravity of the connecting yarn is ρ (g / Cm ³ ), the total cross-sectional area (N · D / 9 × 10 ⁵ · ρ) of the connecting yarn in 5 centimeters of solid knitted fabric is preferably 0.05 to 1.0 cm ² , more preferably Is in the range of 0.3 to 0.6 cm ² , the three-dimensional structure knitted fabric has an appropriate cushioning property and soft feeling, and is optimal. If the total cross-sectional area of the connecting yarn is less than 0.05 cm ² is made cushioning tends to decrease, soft feeling tends to decrease when exceeding 1.0 cm ^2.

The connecting yarn may form loop stitches in the two layers of the front and back layers, or may have a structure that is hooked on the two layers of the front and back layers in a tacky structure. The connecting yarn may be formed by tying the two layers of the knitted fabric on the front and back sides, and may be arranged in an inclined manner or crossed in a truss shape or an X shape as necessary.
The thickness and basis weight of the three-dimensional knitted fabric may be appropriately selected as necessary. For example, the thickness is preferably in the range of 2 to 20 mm, more preferably 3 to 10 mm, and the basis weight is preferably 80 g / m ^{2 to} 700 g / m ² , more preferably 100 to 400 g / m ² .
Such a three-dimensional fabric may be cut into a desired size as necessary, or the cut piece of fabric may be used in a desired shape by sewing or thermoforming.

Next, an example in which the three-dimensionally structured fabric of the present invention is used for a speaker damper will be described.
The speaker damper is obtained by using such a fabric as a base, impregnating it with a thermosetting resin such as phenol resin or melamine resin as an excipient, and press-molding it in a mold under heating. As the excipient, such a thermosetting resin is generally used, but a polyester resin that is cured by a crosslinking agent such as melamine may be used as necessary. The proportion of the excipient is preferably about 15 to 40% by mass with respect to the fabric in terms of dry mass.
The speaker damper preferably has a fabric thickness of about 0.1 to 0.7 mm, and is usually disk-shaped and has a concentric waveform. Moreover, the air permeability measured based on JIS-L-1096 is preferably in the range of 70 to 170 cm ³ / cm ² · sec.

  In addition, for example, when there is a concern about a decrease in the tensile strength of the polyketone fiber due to receiving strong ultraviolet rays outdoors, an ultraviolet absorbent such as a benzophenone-based, benzotriazole-based, hindered amine-based in the form of fiber or fabric Ultraviolet absorber and / or ultraviolet shielding agent combining one or more kinds, for example, fine particles such as titanium oxide, iron oxide, cerium oxide, etc., having an average particle size in the range of 0.01 to 0.6 μm You may make it contain. Examples of the method of inclusion include, for example, a method of applying or coating a resin or film containing an ultraviolet absorber and / or an ultraviolet shielding agent to a fiber or fabric, and the content of the ultraviolet absorber and / or the ultraviolet shielding agent is The range of 0.001 to 10 mass% with respect to the mass of the resin or film is preferred.

Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.
The measurement method and evaluation method in the present invention are as follows.
(1) Tensile strength, tensile elongation, and tensile modulus Measured according to JIS-L-1013.
Sample length: 20 cm, tensile speed: measured at 20 cm / min, and an average value is obtained when measured 20 times.
(2) Durability The evaluation was made by the change with time (after 500 hours) of the lowest resonance frequency in the continuous operation of the 16 cm diameter speaker using the produced damper. In a conventional damper for a speaker using cotton cloth, the rate of change is about -20%.
○: Change rate is −3% or less.
(Triangle | delta); Change rate is -4%--9%.
X: Change rate is -10% or more.

[Example 1]
1670 dtex / 1250f polyketone fiber (manufactured by Asahi Kasei Fibers Co., Ltd .; trade name: Cyvalon; tensile strength 18 cN / dtex, tensile elongation 5%, tensile elastic modulus 350 cN / dtex) According to the ring spinning method, a ring spun yarn of 550 dtex was obtained.
Using a multi-stage opening loom equipped with a dobby opening device (pile loom), the obtained spun yarn is supplied as a warp yarn for the outer fabric, a warp yarn for the backing fabric, and a weft and a connecting yarn. A solid fabric was obtained. The obtained three-dimensional fabric had a warp density of 22.5 / 2.54 cm (same on both sides), a weft density of 45 / 2.54 cm (same on both sides), a connecting yarn density of 506 / 2.54 cm square, and a thickness of 10 mm. It was.
Next, the resulting three-dimensional woven fabric was impregnated with a phenol resin and dried, and after forming a corrugated shape (corrugation) by a hot press process, it was punched into an annular shape by a die cutting process to produce a damper.
The durability of the obtained damper was excellent and excellent. The moldability and the dimensional accuracy of the molded product were also excellent.

[Comparative Example 1]
In Example 1, except for using 1670 dtex / 964f para-aramid fiber multifilament yarn (tensile strength 20 cN / dtex, tensile elongation 4.5%, tensile elastic modulus 500 cN / dtex) instead of polyketone fiber. A damper was prepared in the same manner as in Example 1.
The durability of the obtained damper was Δ, which was inferior to that of Example 1.
[Comparative Example 2]
A damper was produced in the same manner as in Example 1 except that 20th cotton yarn was used.
The durability of the obtained damper was x, which was greatly inferior to that of Example 1.

The three-dimensionally structured fabric of the present invention is particularly suitable as a speaker damper, and provides a speaker damper having excellent durability with little change in the lowest resonance frequency over time. Furthermore, in the case of speakers that are required to be water resistant, for example, in the case of a speaker attached to the door of an automobile, the damper is susceptible to water due to rain water from the window or water leakage during car washing, but the polyketone fiber has water absorption. Since there is almost no damper, it is possible to provide a damper having extremely excellent water resistance.
The three-dimensional structure fabric of the present invention can be used in addition to a speaker damper, and includes a speaker diaphragm, a friction material such as a clutch and a brake, and a connection space portion formed of, for example, a connection thread. Filled with gas, liquid, powder, paste, and the front and back surfaces are coated with rubber such as neoprene and elastomer such as polyvinyl chloride, and it is used as the foundation of a boat hull, underground gas tank, building, or filled with sand or cement. Thus, it can be used as a protective material for construction and submarine cable.

  Furthermore, it can be combined with elastomers such as rubber and resin as composites (fiber composites) or without composites, seat materials for automobiles, railway vehicles, airplanes, etc., interior materials for vehicles such as door trims, office use, etc. Available for seats. In particular, when used as a seat material for a vehicle or the like, the seat material has excellent air permeability and appropriate cushioning properties, and has a good seating comfort by eliminating the stuffiness. Other materials such as furniture, bedding sheets, shoulder pads, brassiere cups, leggers cushions, supporter cushions, lining materials such as warm clothing, linings for helmets, human body protection pads, etc. It can use suitably for uses, such as a material, a shape retention material, a heat retention material. For example, the front and back surfaces are made of polyketone fibers, and monofilament yarns such as polytrimethylene terephthalate, polybutylene terephthalate, and nylon are used as connecting yarns to form a three-dimensional fabric, and the front and / or back surfaces are impregnated with a thermosetting resin. It can also be made into fiber reinforced plastic (FRP), and it can also be set as FRP which has cushioning properties. In addition, FRP applications aimed at light weight, high strength, and high dimensional stability include propellers, various fuel tanks, and vehicles (aircraft, railway vehicles, automobiles, etc.), and as fiber reinforced concrete (FRC) applications. There are various building structural materials.

Claims (1)

A three-dimensionally structured fabric composed of at least two knitted fabrics on the front and back sides and a connecting yarn for linking the two layers of knitted fabric, wherein 95 mol% or more of the repeating units are composed of a polyketone represented by the following formula (1). A three-dimensional fabric characterized in that it contains fibers.