US20150225944A1 - Functional Material for Acoustic Equipment - Google Patents
Functional Material for Acoustic Equipment Download PDFInfo
- Publication number
- US20150225944A1 US20150225944A1 US14/616,503 US201514616503A US2015225944A1 US 20150225944 A1 US20150225944 A1 US 20150225944A1 US 201514616503 A US201514616503 A US 201514616503A US 2015225944 A1 US2015225944 A1 US 2015225944A1
- Authority
- US
- United States
- Prior art keywords
- filler
- acoustic equipment
- functional material
- resin composition
- resin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000000463 material Substances 0.000 title claims abstract description 62
- 239000011342 resin composition Substances 0.000 claims abstract description 38
- 239000000945 filler Substances 0.000 claims abstract description 33
- 239000011148 porous material Substances 0.000 claims abstract description 23
- 239000011347 resin Substances 0.000 claims abstract description 23
- 229920005989 resin Polymers 0.000 claims abstract description 23
- 229920001187 thermosetting polymer Polymers 0.000 claims abstract description 23
- 230000005484 gravity Effects 0.000 claims abstract description 18
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 7
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 4
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 239000000377 silicon dioxide Substances 0.000 claims description 4
- 229910021536 Zeolite Inorganic materials 0.000 claims description 3
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 claims description 3
- 239000010457 zeolite Substances 0.000 claims description 3
- 238000000465 moulding Methods 0.000 abstract description 29
- 239000002245 particle Substances 0.000 description 16
- 239000000835 fiber Substances 0.000 description 14
- 238000011156 evaluation Methods 0.000 description 9
- 239000011256 inorganic filler Substances 0.000 description 8
- 229910003475 inorganic filler Inorganic materials 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- 239000005011 phenolic resin Substances 0.000 description 5
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 4
- 229920001971 elastomer Polymers 0.000 description 4
- -1 aralkyl modified phenol Chemical class 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 229910001369 Brass Inorganic materials 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 239000004760 aramid Substances 0.000 description 2
- 229920003235 aromatic polyamide Polymers 0.000 description 2
- 239000010951 brass Substances 0.000 description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 description 2
- 238000013016 damping Methods 0.000 description 2
- 239000000806 elastomer Substances 0.000 description 2
- 230000002706 hydrostatic effect Effects 0.000 description 2
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 2
- 229910052753 mercury Inorganic materials 0.000 description 2
- 150000002989 phenols Chemical class 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 239000012779 reinforcing material Substances 0.000 description 2
- 238000003856 thermoforming Methods 0.000 description 2
- 239000002023 wood Substances 0.000 description 2
- 229910000906 Bronze Inorganic materials 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 235000019492 Cashew oil Nutrition 0.000 description 1
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229920000800 acrylic rubber Polymers 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229920006231 aramid fiber Polymers 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 1
- 239000010974 bronze Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229940059459 cashew oil Drugs 0.000 description 1
- 239000010467 cashew oil Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- YGANSGVIUGARFR-UHFFFAOYSA-N dipotassium dioxosilane oxo(oxoalumanyloxy)alumane oxygen(2-) Chemical compound [O--].[K+].[K+].O=[Si]=O.O=[Al]O[Al]=O YGANSGVIUGARFR-UHFFFAOYSA-N 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000012784 inorganic fiber Substances 0.000 description 1
- 239000010954 inorganic particle Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000010445 mica Substances 0.000 description 1
- 229910052618 mica group Inorganic materials 0.000 description 1
- 239000011490 mineral wool Substances 0.000 description 1
- 229910052627 muscovite Inorganic materials 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 229920002545 silicone oil Polymers 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 235000019640 taste Nutrition 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000010455 vermiculite Substances 0.000 description 1
- 229910052902 vermiculite Inorganic materials 0.000 description 1
- 235000019354 vermiculite Nutrition 0.000 description 1
- 230000001755 vocal effect Effects 0.000 description 1
- 239000010456 wollastonite Substances 0.000 description 1
- 229910052882 wollastonite Inorganic materials 0.000 description 1
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B26/00—Compositions of mortars, concrete or artificial stone, containing only organic binders, e.g. polymer or resin concrete
- C04B26/02—Macromolecular compounds
- C04B26/10—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- C04B26/12—Condensation polymers of aldehydes or ketones
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/62—Insulation or other protection; Elements or use of specified material therefor
- E04B1/74—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls
- E04B1/82—Heat, sound or noise insulation, absorption, or reflection; Other building methods affording favourable thermal or acoustical conditions, e.g. accumulating of heat within walls specifically with respect to sound only
- E04B1/84—Sound-absorbing elements
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
- C04B38/08—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof by adding porous substances
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/52—Sound-insulating materials
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/002—Devices for damping, suppressing, obstructing or conducting sound in acoustic devices
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/02—Casings; Cabinets ; Supports therefor; Mountings therein
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only
- H04R1/28—Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means
- H04R1/2869—Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself
- H04R1/2884—Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself by means of the enclosure structure, i.e. strengthening or shape of the enclosure
- H04R1/2888—Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself by means of the enclosure structure, i.e. strengthening or shape of the enclosure for loudspeaker transducers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R31/00—Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor
Definitions
- This invention relates to a functional material made by molding a resin composition, which is preferable for a functional material used for an acoustic equipment.
- a material As a functional material for acoustic equipment, a material has an internal loss like wood to absorb unnecessary external vibration, and a high rigidity and a high specific gravity to avoid unnecessary resonance of itself due to the external vibration without attenuating necessary vibration.
- the Patent Document 1 discloses a resin composition to make a material for acoustic equipment by molding that includes a thermosetting resin and an inorganic filler and is characterized that the inorganic filler partially or entirely is in a needle shape with 1-20 ⁇ m particle size measured by the sedimentation method.
- the Patent Document 2 discloses a thermosetting resin composition for acoustic equipment characterized that the filler composed of 60-90 weight % of a heavy calcium carbonate with 250-10 ⁇ m particle size and 10-40 weight % of an inorganic powder with 8-0.1 ⁇ m particle size are added to a phenol resin in the ratio of 35-80 weight % relative to the entire amount to be mixed, kneaded, and crushed.
- the Patent Document 3 discloses a resin composition to make a structural material for acoustic equipment by molding characterized that a resin composition includes a thermosetting resin, a curing agent, an inorganic filler, and a fiber reinforcing material and an aromatic polyamide fiber is used for the fiber reinforcing material.
- the Patent Document 4 discloses a resin composition to make a material for acoustic equipment by molding characterized that a resin composition includes a thermosetting resin and an inorganic filler and that a part or entire inorganic filler is an amorphous inorganic small short fiber.
- the Patent Document 5 discloses a resin composition to make a material for the acoustic equipment by molding characterized that a resin composition does not include a thermosetting resin and an inorganic filler but a reactive liquid rubber is added therein.
- Patent Document 1 Japanese Provisional Patent Publication No. 1983-53952
- Patent Document 2 Japanese Provisional Patent Publication No. 1983-89644
- Patent Document 3 Japanese Provisional Patent Publication No. 1983-104949
- Patent Document 4 Japanese Provisional Patent Publication No. 1983-215433
- Patent Document 5 Japanese Provisional Patent Publication No. 1984-30858
- thermosetting resin and inorganic filler have innumerable communicating minute pores inside.
- the inventors diligently investigated, as assuming that the necessary vibration attenuation occurs due to viscous resistance of the air involved in the pores, and found that the functional material for acoustic equipment with more superior acoustic performance than the conventional materials can be obtained by maintaining the porosity of the molded materials and the average pore size within a predetermined range.
- This invention relates to the functional material for acoustic equipment made by molding the resin compositions suitable for the functional material used for acoustic equipment and is based on the following technology.
- the functional material for acoustic equipment made by molding the resin compositions composed of the thermosetting resin and filler is such that the specific gravity of the molded material is between 1.5 and 5.0, the porosity is between 2-20%, and the average pore size of 0.1-3 ⁇ m.
- This invention can provide the functional material for acoustic equipment made by molding and curing the resin compositions composed of the thermosetting resin and the filler that provides more preferable acoustic performance than the conventional materials, such performance including such as maintenance of the preferable moldability, elimination of uncomfortable low frequency vibration, creation of the comfortable natural sound, high and low sound areas expansion, and creation of depth of sound.
- the functional material for acoustic equipment of this invention is characterized that the functional material is made by molding the resin compositions composed of the thermosetting resin and filler and has the molded material specific gravity of 1.5-5.0, the porosity of 2-20%, and the average pore size of 0.1-3.0 ⁇ m.
- the specific gravity of the material can be adjusted by selecting the type of the filler to be added to the resin compositions appropriately.
- the porosity and the average pore size can be adjusted by changing the molding conditions such as the molding temperature, the molding pressure, and the molding time; however, an excessive consideration and examination of the molding conditions are necessary until preferable porosity and average pore size can be obtained.
- this invention resolved the problem by adding the porous filler of 10-35 weight % relative to the entire amount of the resin compositions as a part of the filler to the resin compositions.
- the molded article with desirable porosity and average pore size can be obtained, without excessive consideration of the molding pressure, by molding at the molding temperature between 130 and 170 centigrade, the molding pressure between 20 and 40 MPa, and the molding time between 2 and 15 minutes.
- the porous filler can be a porous filler with a micro porous structure at 2 nm or less average pore diameter, a porous filler with a meso-porous structure at more than 2 nm but less than 50 nm average pore diameter, or a porous filler where the porous filler has a micro porous structure at 50 nm or more average pore diameter.
- the amount of use of the porous filler is decreased and then flexibility to adjust the amount of addition of other fillers increases, therefore, it becomes easy for favorable thing to adjust the specific gravity.
- the porous filer with the micro porous structure can be any one of or combination of zeolite, active carbon, porous silica, and porous alumina.
- the specific gravity in this invention is used the value measured by Pycnometer and Hydrostatic Method, and the porosity and average pore size are used the values measured by Mercury Porosimeter using the test pieces cutting from the functional material for acoustic equipment.
- thermosetting resin can be one of or any combination of such as straight phenol resin, modified phenol resin modified by cashew oil, silicone oil, or various elastomers such as acrylic rubber, the aralkyl modified phenol resin formed by reacting phenol compounds, aralkyl ether compounds, and aldehyde compounds, and the thermosetting resin dispersing such as various elastomers and fluorine polymer in the phenol resin.
- thermosetting resin in the amount of 5-20 weight % relative to the entire resin compositions is added. If the amount of the thermosetting resin added therein is less than 5 weight %, the molded article tends to be cracked, and if the amount of the thermosetting resin added exceeds 25 weight %, a blister occurs in the molded article.
- the filler other than the above-described porous filler can be one of or any combination of an organic fiber such as aramid fiber, PAN fiber, and cellulose fiber, an inorganic fiber such as glass fiber and rock wool, an inorganic particle such as calcium carbonate, sulfuric acid, barium, a mica, a talk, a wollastonite, a vermiculite, alumina, silica, zirconia, and zirconium silicate, a carbon particle such as coke and graphite, a rubber particle such as NBR particle and SBR particle, a particle or a short fiber made of metal such as copper, brass, bronze, aluminum, stainless steel, and steel.
- an organic fiber such as aramid fiber, PAN fiber, and cellulose fiber
- an inorganic fiber such as glass fiber and rock wool
- an inorganic particle such as calcium carbonate, sulfuric acid, barium, a mica, a talk, a wollastonite, a vermiculite, alumina, silica
- the functional material for acoustic equipment of this invention is manufactured through steps of mixing the thermosetting resin and filler evenly into the predetermined amount of the resin compositions in a mixer, molding the mixture after placing the mixture in the predetermined shaped thermoforming mold to heat the same at 130-170 centigrade under the pressure of 20-40MPa for 2-15 minutes, and grinding the surface to make the predetermined roughness of the surface.
- a perforating a bore for screw-engaging with acoustic equipment is manufactured through steps of mixing the thermosetting resin and filler evenly into the predetermined amount of the resin compositions in a mixer, molding the mixture after placing the mixture in the predetermined shaped thermoforming mold to heat the same at 130-170 centigrade under the pressure of 20-40MPa for 2-15 minutes, and grinding the surface to make the predetermined roughness of the surface.
- a perforating a bore for screw-engaging with acoustic equipment is manufactured through steps of mixing the thermosetting resin and filler evenly into the predetermined amount of the resin compositions in a mixer,
- the resin compositions with the compositions described in Table 1 is mixed in a Loedige mixer for about 5 minutes, and after the obtained mixture is placed in the thermoforming mold to mold under the conditions described in Table 1, the resulted article is processed to be in 100 mm ⁇ 55 mm ⁇ 5 mm to obtain the functional material for acoustic equipment according to the comparative examples 1-5.
- Moldability evaluation standard is described as follows:
- the sound facilities include a power amplifier (Esoteric A-03), a D/A converter, an amplifier, a compact disc player (Esoteric K-05), and a large speaker (B&W 801D).
- the power amplifier, the D/A converter and the speaker that output analog signals and tend to show the sound quality variation easily are three point mounted (right, left, and back center) on the functional material for acoustic equipment according to the embodiments 1-6 and the comparative examples 1-5 are placed under.
- the functional material is placed separately and independently under the power amplifier, the D/A converter, and the speaker.
- Evolution points are (1) uncomfortable low frequency vibration by the influence of pores of the material and (2) comfortable natural sound by the influence of the specific gravity of the material relative to the sound frequency resonance in addition to the low pitched tone enhancement, feeling of sound depth, and high pitched tone enhancement.
- Evaluators are selected from a unisex group of 20 people aged between 22 and 62 with different tastes, and the results are based on the average of the evaluators' judges.
- the valuation basis of the acoustic performance are as follows:
- the functional material for acoustic equipment of this invention made by molding and curing the resin compositions composed of the thermosetting resin and the filler shows superior sound performance to the conventional material and is suitable for an audio board, an insulator (acoustic equipment foot, transformer vibration damping board, and speaker unit vibration damping board) , a tuning panel, an acoustic equipment box, an audio rack, and a speaker box material.
Abstract
[Object] To provide the functional material for acoustic equipment of this invention made by molding and curing the resin composition consisting of a thermosetting resin and a filler shows superior sound performance to the conventional material.
[Means to Resolve] The functional material for acoustic equipment made by molding the resin composition consisting of the thermosetting resin and the filler, where a specific gravity of the molded material is between 1.5 and 5.0, the porosity of the molded materials is between 2% and 20%, and the average pore size of the materials is between 0.1 μm and 3.0 μm. The resin composition has 5-25 weight % of the thermosetting resin relative to the entire amount of the resin compositions and the filler of the resin composition partially includes 10-35 weight % of the porous filler (preferably having micro porous structure) relative to the entire resin composition.
Description
- This invention relates to a functional material made by molding a resin composition, which is preferable for a functional material used for an acoustic equipment. This application claims priority to previously filed U.S. Provisional patent application No. 61/938,866 filed on 2014 Apr. 12 and the contents of which is incorporated herewith.
- Generally, as a functional material for acoustic equipment, a material has an internal loss like wood to absorb unnecessary external vibration, and a high rigidity and a high specific gravity to avoid unnecessary resonance of itself due to the external vibration without attenuating necessary vibration.
- As the material described above, a material made by molding a resin composition consisting of a thermosetting resin and inorganic fillers have been invented.
- The Patent Document 1 discloses a resin composition to make a material for acoustic equipment by molding that includes a thermosetting resin and an inorganic filler and is characterized that the inorganic filler partially or entirely is in a needle shape with 1-20 μm particle size measured by the sedimentation method.
- The Patent Document 2 discloses a thermosetting resin composition for acoustic equipment characterized that the filler composed of 60-90 weight % of a heavy calcium carbonate with 250-10 μm particle size and 10-40 weight % of an inorganic powder with 8-0.1 μm particle size are added to a phenol resin in the ratio of 35-80 weight % relative to the entire amount to be mixed, kneaded, and crushed.
- The Patent Document 3 discloses a resin composition to make a structural material for acoustic equipment by molding characterized that a resin composition includes a thermosetting resin, a curing agent, an inorganic filler, and a fiber reinforcing material and an aromatic polyamide fiber is used for the fiber reinforcing material.
- The Patent Document 4 discloses a resin composition to make a material for acoustic equipment by molding characterized that a resin composition includes a thermosetting resin and an inorganic filler and that a part or entire inorganic filler is an amorphous inorganic small short fiber.
- The Patent Document 5 discloses a resin composition to make a material for the acoustic equipment by molding characterized that a resin composition does not include a thermosetting resin and an inorganic filler but a reactive liquid rubber is added therein.
- These materials have internal losses equal to wood and to rigidity and a specific gravity are high, which are designed to provide a better acoustic property; however, a further development on these materials is on demand.
- [Patent Document 1] Japanese Provisional Patent Publication No. 1983-53952
- [Patent Document 2] Japanese Provisional Patent Publication No. 1983-89644
- [Patent Document 3] Japanese Provisional Patent Publication No. 1983-104949
- [Patent Document 4] Japanese Provisional Patent Publication No. 1983-215433
- [Patent Document 5] Japanese Provisional Patent Publication No. 1984-30858
- It is an object of this invention to provide a functional material for acoustic equipment by molding and curing resin compositions, which eliminates unpleasant and uncomfortable low frequency vibration but provides, comparing to the conventional materials, more preferable acousticity such as a comfortable natural sound, high and low sound area expansion, and depth of sound.
- The resin compositions made from such as the thermosetting resin and inorganic filler have innumerable communicating minute pores inside.
- The inventors diligently investigated, as assuming that the necessary vibration attenuation occurs due to viscous resistance of the air involved in the pores, and found that the functional material for acoustic equipment with more superior acoustic performance than the conventional materials can be obtained by maintaining the porosity of the molded materials and the average pore size within a predetermined range.
- This invention relates to the functional material for acoustic equipment made by molding the resin compositions suitable for the functional material used for acoustic equipment and is based on the following technology.
- (1) The functional material for acoustic equipment made by molding the resin compositions composed of the thermosetting resin and filler is such that the specific gravity of the molded material is between 1.5 and 5.0, the porosity is between 2-20%, and the average pore size of 0.1-3 μm.
- (2) The functional material for acoustic equipment as described in (1), where the above-resin compositions include the thermosetting resin of 5-25 weigh % relative to the entire amount of the resin composition.
- (3) The functional material for acoustic equipment as described in the above (1) or (2), where the above-resin compositions include the filler partially involving porous filler of 10-35 weight % relative to the entire amount of resin compositions.
- (4) The functional material for acoustic equipment as described in the above (3), where the porous filler has a micro porous structure.
- (5) The functional material for acoustic equipment as described in the above (4), where the filler having the micro porous structure is one or more selected from a group of zeolite, activated carbon, porous silica, or porous alumina.
- This invention can provide the functional material for acoustic equipment made by molding and curing the resin compositions composed of the thermosetting resin and the filler that provides more preferable acoustic performance than the conventional materials, such performance including such as maintenance of the preferable moldability, elimination of uncomfortable low frequency vibration, creation of the comfortable natural sound, high and low sound areas expansion, and creation of depth of sound.
- The functional material for acoustic equipment of this invention is characterized that the functional material is made by molding the resin compositions composed of the thermosetting resin and filler and has the molded material specific gravity of 1.5-5.0, the porosity of 2-20%, and the average pore size of 0.1-3.0 μm.
- By arranging the specific gravity of the molded material 1.5-5.0, the porosity of the same 2-20%, and the average pore size of the same 0.1-3.0 μm, a chance of attenuating the necessary vibration is eliminated, thereby providing the functional material for acoustic equipment with superior acoustic performance.
- The specific gravity of the material can be adjusted by selecting the type of the filler to be added to the resin compositions appropriately.
- The porosity and the average pore size can be adjusted by changing the molding conditions such as the molding temperature, the molding pressure, and the molding time; however, an excessive consideration and examination of the molding conditions are necessary until preferable porosity and average pore size can be obtained.
- Then, this invention resolved the problem by adding the porous filler of 10-35 weight % relative to the entire amount of the resin compositions as a part of the filler to the resin compositions.
- By adding the porous filler having innumerable small pores, the molded article with desirable porosity and average pore size can be obtained, without excessive consideration of the molding pressure, by molding at the molding temperature between 130 and 170 centigrade, the molding pressure between 20 and 40 MPa, and the molding time between 2 and 15 minutes.
- The porous filler can be a porous filler with a micro porous structure at 2 nm or less average pore diameter, a porous filler with a meso-porous structure at more than 2 nm but less than 50 nm average pore diameter, or a porous filler where the porous filler has a micro porous structure at 50 nm or more average pore diameter.
- By using the porous filler with the micro porous structure, the amount of use of the porous filler is decreased and then flexibility to adjust the amount of addition of other fillers increases, therefore, it becomes easy for favorable thing to adjust the specific gravity.
- The porous filer with the micro porous structure can be any one of or combination of zeolite, active carbon, porous silica, and porous alumina.
- The specific gravity in this invention is used the value measured by Pycnometer and Hydrostatic Method, and the porosity and average pore size are used the values measured by Mercury Porosimeter using the test pieces cutting from the functional material for acoustic equipment.
- The thermosetting resin can be one of or any combination of such as straight phenol resin, modified phenol resin modified by cashew oil, silicone oil, or various elastomers such as acrylic rubber, the aralkyl modified phenol resin formed by reacting phenol compounds, aralkyl ether compounds, and aldehyde compounds, and the thermosetting resin dispersing such as various elastomers and fluorine polymer in the phenol resin.
- The thermosetting resin in the amount of 5-20 weight % relative to the entire resin compositions is added. If the amount of the thermosetting resin added therein is less than 5 weight %, the molded article tends to be cracked, and if the amount of the thermosetting resin added exceeds 25 weight %, a blister occurs in the molded article.
- The filler other than the above-described porous filler can be one of or any combination of an organic fiber such as aramid fiber, PAN fiber, and cellulose fiber, an inorganic fiber such as glass fiber and rock wool, an inorganic particle such as calcium carbonate, sulfuric acid, barium, a mica, a talk, a wollastonite, a vermiculite, alumina, silica, zirconia, and zirconium silicate, a carbon particle such as coke and graphite, a rubber particle such as NBR particle and SBR particle, a particle or a short fiber made of metal such as copper, brass, bronze, aluminum, stainless steel, and steel.
- The functional material for acoustic equipment of this invention is manufactured through steps of mixing the thermosetting resin and filler evenly into the predetermined amount of the resin compositions in a mixer, molding the mixture after placing the mixture in the predetermined shaped thermoforming mold to heat the same at 130-170 centigrade under the pressure of 20-40MPa for 2-15 minutes, and grinding the surface to make the predetermined roughness of the surface. In addition, as necessary, a perforating a bore for screw-engaging with acoustic equipment.
- The following sections show the embodiments and comparative examples of this invention to concretely explain this invention; however, the following embodiments do not limit the scope of this invention.
- The resin compositions with the compositions described in Table 1 is mixed in a Loedige mixer for about 5 minutes, and after the obtained mixture is placed in the thermoforming mold to mold under the conditions described in Table 1, the resulted article is processed to be in 100 mm×55 mm×5 mm to obtain the functional material for acoustic equipment according to the comparative examples 1-5.
- With respect to the functional material for acoustic equipment in the embodiments 1-6 and the comparative examples 1-5, the evaluation as to the physical property, the moldability, and the acoustic performance are conducted as below. The evaluation result is explained with Table 1.
- Physical Property Evaluation. Specific gravity is determined by Pycnometer and Hydrostatic Method, and the porosity and the average pore size are determined by the Mercury Porosimeter (Yuasa lonicsCo., Ltd).
- Moldability Evaluation. Moldability evaluation standard is described as follows:
-
- ∘: no crack and blister
- x: crack and blister
- Acoustic Performance Evaluation. Acoustic performance evaluation is conducted in the acoustic audio room. The sound facilities include a power amplifier (Esoteric A-03), a D/A converter, an amplifier, a compact disc player (Esoteric K-05), and a large speaker (B&W 801D). The power amplifier, the D/A converter and the speaker that output analog signals and tend to show the sound quality variation easily are three point mounted (right, left, and back center) on the functional material for acoustic equipment according to the embodiments 1-6 and the comparative examples 1-5 are placed under. Here, the functional material is placed separately and independently under the power amplifier, the D/A converter, and the speaker.
- Evolution points are (1) uncomfortable low frequency vibration by the influence of pores of the material and (2) comfortable natural sound by the influence of the specific gravity of the material relative to the sound frequency resonance in addition to the low pitched tone enhancement, feeling of sound depth, and high pitched tone enhancement.
- An evaluating music having sound sources with different frequency emphasizing the instruments being used for the total evaluation.
-
- Japanese popular music in 1970-1980's (vocal, guitar, bass guitar, and drum: 30 Hz-18 kHz: center 400 Hz-3 kHz)
- jazz music (piano: 30 Hz-5 kHz: center 200 Hz-1 kHz)
- classical music (orchestral music: 100 Hz-4 kHz: center 300 Hz-2 kHz)
- rock music (guitar, bass guitar, drum, keyboard Instrument: 40 Hz-18 kHz: center 100 Hz-1 kHz)
- Evaluators are selected from a unisex group of 20 people aged between 22 and 62 with different tastes, and the results are based on the average of the evaluators' judges. The valuation basis of the acoustic performance are as follows:
- ⊚: 15-20 people judge it to be good
- ∘: 10-14 people judge it to be good
- Δ: 5-9 people judge it to be good
- x: 0-4 people judge it to be good
-
TABLE 1 Embodiments Comparative Examples 1 2 3 4 5 6 1 2 3 4 5 Composition Straight phenol 15.0 5.0 25.0 5.0 25.0 15.0 15.0 2.0 30.0 25.0 5.0 (Weight %) resin Aramid pulp 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 (ave. fiber diameter 1 μm, ave. fiber length 3 μm) Muscovite (ave. 10.0 10.0 10.0 3.0 30.0 10.0 10.0 10.0 10.0 3.0 3.0 fiber diameter 10 μm, ave. fiber length 200 μm) Brass fiber (ave. 25.0 25.0 20.0 45.0 0.0 25.0 25.0 25.0 25.0 0.0 45.0 fiber diameter 150 μm, ave. fiber length 3 μm) Cast iron 25.0 20.0 20.0 40.0 0.0 25.0 25.0 25.0 25.0 0.0 45.0 particle (ave. particle diameter 80 μm) NBR particle 0.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 70.0 0.0 (ave. particle diameter 90 μm) Active carbon 10.0 10.0 10.0 5.0 35.0 0.0 10.0 10.0 8.0 0.0 0.0 particle (ave. particle diameter 120 μm) Zeoite (ave. 0.0 0.0 0.0 0.0 0.0 10.0 0.0 0.0 0.0 0.0 0.0 particle diameter 6 μm) Calcium 13.0 23.0 13.0 0.0 8.0 13.0 13.0 26.0 0.0 0.0 0.0 carbonate (ave. particle diameter 6 μm) Total 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 Molding Molding temp. 150 150 150 150 150 150 130 150 150 150 150 (° C.) Molding 30 30 30 30 30 30 3 30 30 30 30 pressure (MPa) Molding time 8 8 8 8 8 8 8 8 8 8 8 (minutes) Physical Specific gravity 2.9 2.7 2.5 4.3 1.8 2.8 2.5 3.1 2.6 1.1 5.4 Property Porosity (%) 5.0 15.0 2.0 20.0 10.0 6.0 25.0 20.0 1.0 0.3 5.0 Ave. pore size 0.4 1.5 0.1 3.0 0.3 0.5 1.3 5.0 0.1 0.1 0.9 (μm) Evaluation Moldability ◯ ◯ ◯ ◯ ◯ ◯ ◯ Δ Δ ◯ ◯ Result Uncomfortable ◯ ⊚ ◯ ◯ ⊚ ◯ X ◯ X ◯ Δ low frequency vibration (porosity) Comfortable ⊚ ⊚ ◯ ◯ ◯ ⊚ Δ X Δ X Δ natural sound (specific gravity, pore size) Low pitched ◯ ◯ ◯ ⊚ ⊚ ◯ Δ ◯ Δ Δ X tone enhancement (specific gravity, pore size) Feeling of ⊚ ◯ ◯ ◯ ◯ ⊚ Δ Δ Δ X Δ sound depth (specific gravity, pore size) High pitched ⊚ ⊚ ⊚ ⊚ ◯ ⊚ ◯ ◯ ◯ Δ X tone enhancement (specific gravity, pore size) ave. = average temp. = temperature - From the results in Table 1, maintaining the porosity and the specific gravity within the predetermined range reduces the unconformable low frequency vibration and provides the functional material for acoustic equipment with preferable sound performance such as comfortable natural sound, low pitched sound enhancement, sound depth feeling, and high pitched sound enhancement. Also, the material is superior in its moldability.
- The functional material for acoustic equipment of this invention made by molding and curing the resin compositions composed of the thermosetting resin and the filler shows superior sound performance to the conventional material and is suitable for an audio board, an insulator (acoustic equipment foot, transformer vibration damping board, and speaker unit vibration damping board) , a tuning panel, an acoustic equipment box, an audio rack, and a speaker box material.
Claims (5)
1. Functional material for acoustic equipment, which is a molded resin composition consisting of a thermosetting resin and a filler, wherein
a specific gravity of the molded material is between 1.5 and 5.0,
a porosity of the molded material is between 2% and 20%, and
an average pore size of the material is between 0.1 μm and 3.0 μm.
2. The functional material for acoustic equipment according to claim 1 , wherein
said resin composition has 5-25 weight % of the thermosetting resin relative to the entire amount of the resin composition.
3. The functional material for acoustic equipment according to claim 1 , wherein
said filler of the resin composition partially includes 10-35 weight % of a porous filler relative to the entire resin composition.
4. The functional material for acoustic equipment according to claim 3 , wherein
said porous filler has a micro porous structure.
5. The functional material for acoustic equipment according to claim 4 , wherein
said porous filler with the micro porous structure is one or more selected from a group of zeolite, active carbon, porous silica, and porous alumina.
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US10570607B2 (en) * | 2018-01-24 | 2020-02-25 | Cs Inventions, Llc | Acoustic shell for stage performances |
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CN107046665B (en) * | 2017-03-30 | 2019-10-22 | 歌尔股份有限公司 | Composite ceramics sound-absorbing part and sounding device mould group |
CN108706912A (en) * | 2018-03-19 | 2018-10-26 | 重庆大学 | A kind of poly- sand sound absorber and preparation method thereof |
US11832050B2 (en) * | 2018-09-19 | 2023-11-28 | Apple Inc. | Zeolitic material for improving loudspeaker performance |
CN115746497A (en) * | 2022-10-14 | 2023-03-07 | 歌尔股份有限公司 | Shell of sound generating device, sound generating device with shell and electronic equipment |
JP7252687B1 (en) * | 2022-11-10 | 2023-04-05 | 株式会社金井製作所 | A virtual earth, its materials and a kit for making a virtual earth |
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JP5654150B1 (en) | 2015-01-14 |
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