close

Вход

Забыли?

вход по аккаунту

?

JP2003244788

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JP2003244788
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a
speaker edge material used for an edge portion provided on the outer periphery of a diaphragm
of a speaker.
[0002]
2. Description of the Related Art In order to improve the acoustic characteristics, the edge
provided on the outer peripheral portion of the diaphragm of the speaker does not suppress the
vibration of the diaphragm or the edge itself does not abnormally vibrate such as resonance.
There is also a need for various properties such as having the internal loss necessary to
sufficiently dampen extra vibrations of the diaphragm. Conventionally, in order to meet the
above-mentioned demand, for example, various edges made of the following materials have been
developed. That is, a fiber type made by impregnating a woven or non-woven fabric of natural
fibers or synthetic fibers with a thermosetting resin, heat-pressing and forming it, and applying a
dumping agent (damping agent) to this, about 30 times A urethane compression type finished by
impregnating foamed urethane foam with bitumen, heat pressed and finished, and a rubber type
finished by molding using a rubber compound containing a vulcanizing agent with a
predetermined molding die can give.
[0003]
12-05-2019
1
However, the various edges described above have the following disadvantages. The abovementioned fiber type makes the application operation of the dumping agent complicated, and the
quality of the product obtained varies. Moreover, the above-mentioned urethane compression
type causes bleeding of bitumen. Furthermore, since the hardness of the molded product changes
with the outside air temperature, the sound quality may vary in the speaker incorporating this.
Furthermore, it has the problem of being inferior to a weather resistance and water resistance.
And, with the above-mentioned rubber type, the weight of the product itself is increased due to
the forming material. Therefore, the vibration can not be followed, and as a result, the sensitivity
of the speaker is reduced. As described above, the various edge types of the prior art each have
problems, are high quality, have good processability, are less affected by the outside air
temperature, and have a speaker edge material excellent in acoustic characteristics. It is
requested. From such a demand, a vulcanized foam edge material comprising a visco-elastic foam
obtained by vulcanizing and foaming a viscous rubber mixture has been proposed.
[0004]
However, the above-mentioned vulcanized foam edge material also has the following
disadvantages. That is, when the speaker is reproduced at a low temperature such as -45.degree.
C., there is a problem that the edge material itself exceeds the glass transition temperature and is
destroyed and the function as the speaker edge is lost.
[0005]
The present invention has been made in view of such circumstances, and provides a speaker edge
material capable of maintaining its function over a long period of time even when used under
severe low temperature conditions such as -45 ° C. To aim.
[0006]
SUMMARY OF THE INVENTION In order to achieve the above object, the speaker edge material
of the present invention comprises an organic polymer material molded body having a glass
transition temperature of -45.degree.
[0007]
That is, the inventor conducted a series of studies to obtain a speaker edge material that can
12-05-2019
2
maintain its function even when used for a long time under severe low temperature conditions
such as -45 ° C.
As a result, it was found that when the molded article of the organic polymer material having a
glass transition temperature of -45.degree.
[0008]
In particular, 50 parts or more of a paraffinic oil having a kinematic viscosity (100 ° C.) of 5 to
12 mm 2 / S is compounded with 100 parts by weight of ethylene-propylene-terpolymer
(hereinafter abbreviated as “parts”) When it is molded using the organic polymer material, the
compatibility with the ethylene-propylene-terpolymer is good, and a foamed sheet can be easily
obtained at the time of vulcanization and foaming.
[0009]
DETAILED DESCRIPTION OF THE INVENTION The present invention will now be described in
detail.
[0010]
The speaker edge material of the present invention comprises an organic polymer material
molding having specific properties.
[0011]
The organic polymer material molded body having the above-mentioned specific properties can
be obtained, for example, by vulcanizing and foaming a rubber component and a softener.
[0012]
The rubber is not particularly limited and conventionally known rubbers such as styrenebutadiene rubber (SBR), nitrile-butadiene rubber (NBR), ethylene-propylene-terpolymer rubber
(EPDM), isoprene rubber (IR) And synthetic rubbers such as chloroprene rubber (CR),
isobutylene-isoprene rubber (IIR), ethylene-propylene rubber (EPR), silicone rubber and the like.
These may be used alone or in combination of two or more.
12-05-2019
3
Among them, it is particularly preferable to use ethylene-propylene-terpolymer rubber (EPDM)
from the viewpoint of moldability and durability.
Furthermore, among the EPDMs, those having a Mooney viscosity [ML (1 + 4) 100 ° C.] of 15 or
more are preferably used.
Usually, the upper limit of the Mooney viscosity is 74.
As described above, by using one having a Mooney viscosity [ML (1 + 4) 100 ° C.] of 15 or
more, it is possible to knead many oils.
[0013]
As the softener used together with the above rubber component, various softeners conventionally
used, for example, plasticizers such as dioctyl phthalate and dibutyl phthalate, lubricating oils
such as spindle oil, machine oil and cylinder oil, paraffin type process Process oil such as oil,
naphthene process oil, petroleum softener such as liquid paraffin, paraffin such as petroleum
jelly, coal tar softener such as coal tar, coal tar pitch, etc. aliphatic system such as castor oil,
cotton seed oil Examples thereof include softeners, waxes such as beeswax and lanolin, resins
which are liquid or solid at normal temperature, and other liquid rubbers such as polybutene.
These are used alone or in combination of two or more because of their compatibility with the
respective rubbers. In the case of using EPDM as the rubber component, it is particularly
preferable to use, for example, a paraffinic process oil from the viewpoint of compatibility.
Among them, it is preferable to use a paraffinic oil having a kinematic viscosity (100 ° C.) of 5
to 12 mm 2 / S. When paraffin oil having a kinematic viscosity (100 ° C.) in the above range is
used, compatibility with rubber components such as ethylene-propylene-terpolymer is good, and
foam sheet can be easily obtained during vulcanization foaming. become. In addition, the said
dynamic viscosity (100 degreeC) is measured according to JISK2283, for example.
[0014]
And it is preferable to set the compounding ratio of the said softener to 50 parts or more with
12-05-2019
4
respect to 100 parts of rubber components, More preferably, it is 60-90 parts. That is, if the
blending ratio of the softener is less than 50 parts, it is difficult to obtain a glass transition
temperature of -45 ° C, and mold flowability tends to be deteriorated.
[0015]
Usually, a vulcanizing agent and an organic blowing agent are used together with the above
rubber component and the softener.
[0016]
Examples of the above-mentioned vulcanizing agent include conventionally known ones. For
example, sulfur compounds such as sulfur, sulfur chloride and sulfur dichloride, oximes such as
p-quinone dioxime, and carbamates such as hexadiamine carbamate and ethylene diamine
carbamate And other selenium, lithium surge, etc.
These may be used alone or in combination of two or more. Particularly preferred is, for example,
the use of sulfur from the viewpoint of rapid vulcanization by molding. And it is preferable to set
the compounding ratio of the said vulcanizing agent to the range of 0.1-10 parts with respect to
100 parts of rubber components, Especially preferably, it is 1-3 parts. That is, if the
compounding ratio of the vulcanizing agent is less than 0.1 part, vulcanization tends to be
insufficient, and if it exceeds 10 parts, the rubber elasticity tends to be strong.
[0017]
Further, as the organic foaming agent, nitroso compounds such as N, N'dinitrosopentamethylenetetramine (DPT), N, N'-dimethyl-N, N'-dinitrosotephthalamide,
azodicarbonamide (ADCA) And azo compounds such as azobisisobutyronitrile and
diazoaminobenzene; and sulfonyl hydrazide compounds such as benzene sulfonyl hydrazide and
toluene sulfonyl hydrazide. In addition, known foaming agents such as p-toluenesulfonyl azide,
4,4'-diphenylsulfonyl azide, p, p'-oxybis (benzenesulfonyl hydrazide) (OBSH) and the like can also
be mentioned. These may be used alone or in combination of two or more. It is particularly
preferable to use, for example, azodicarbonamide (ADCA) in view of heating and temperatureinduced gas generation. And it is preferable to set the compounding ratio of the said organic
foaming agent to the range of 0.1-30 parts with respect to 100 parts of rubber components,
More preferably, it is 1-20 parts. That is, if the blending ratio of the organic blowing agent is less
12-05-2019
5
than 0.1 part, the foaming becomes insufficient, and if it exceeds 30 parts, outgassing tends to
occur.
[0018]
As the organic polymer material which is a material for forming the speaker edge material of the
present invention, in addition to the above-mentioned rubber component, softener, vulcanizing
agent, and organic foaming agent, it is possible to accelerate vulcanization as another additive as
needed. An agent, a filler, a rubber reinforcing agent, an ultraviolet light absorber, an antiaging
agent, a foaming auxiliary, a vulcanization accelerating auxiliary, a lubricant and the like can be
appropriately blended.
[0019]
Examples of the vulcanization accelerator include guanidine compounds such as
diphenylguanidine and triphenylguanidine, thiazole compounds such as 2-mercaptobenzothiazole
and dibenzothiazole disulfide, thiourea compounds such as thiocarbanilide and diethylthiourea,
and tetramethylthiuram mono Thiuram compounds such as sulfide and tetramethylthiuram
disulfide, and dithiocarbamate compounds such as zinc dimethyldithiocarbamate and sodium
dimethyldithiocarbamate.
These may be used alone or in combination of two or more.
[0020]
Examples of the filler include inorganic fillers such as calcium carbonate, talc, clay, asbestos,
pumice powder, glass fibers, mica, silica, hollow beads and the like. In addition, organic fillers
such as recycled rubber, shellac, wood powder, cork powder and the like can be mentioned.
These may be used alone or in combination of two or more. Particularly in these fillers, in order
to carry out molding foaming uniformly, those having uniform viscosity and good dispersibility
are preferable. And, in terms of weight reduction of the speaker edge material, it is preferable to
use, for example, talc and silica.
[0021]
12-05-2019
6
Examples of the rubber reinforcing agent include carbon black such as channel black and furnace
black, silicas and the like. These may be used alone or in combination of two or more.
[0022]
Examples of the above-mentioned vulcanization acceleration assistant include metal oxides such
as zinc oxide and magnesium oxide. These may be used alone or in combination of two or more.
[0023]
Examples of the ultraviolet absorber include benzophenone compounds and benzotriazole
compounds.
[0024]
Examples of the antiaging agent include phenol compounds, amine ketone compounds, and
aromatic amine compounds.
[0025]
Examples of the foaming aid include urea and salicylic acid.
[0026]
Examples of the lubricant include stearic acid and the like.
[0027]
The mixing ratio of the above-mentioned other additives is 0.1 to 20 parts of the vulcanization
accelerator, 200 parts or less of the filler, more preferably 10 to 200 parts of the rubber
accelerator, per 100 parts of the rubber component. 10 to 100 parts, 0.1 to 10 parts of a
vulcanization accelerator, 0.1 to 10 parts of an ultraviolet absorber, 0.1 to 10 parts of an
antiaging agent, 0.1 to 100 parts of a foaming aid The lubricant is preferably set to 1 to 5 parts.
[0028]
12-05-2019
7
The organic polymer material which is a formation material of the speaker edge material of this
invention is produced as follows, for example.
That is, the rubber component, the softener, the vulcanizing agent, the organic foaming agent
and, if necessary, other additives are appropriately blended and produced.
The organic polymer material produced in this manner has a Mooney viscosity [ML (1 + 4) 100
° C.] set in the range of 1 to 30, using this so-called speaker edge material Preferred for
production, and particularly preferred is Mooney viscosity [ML (1 + 4) 100 ° C] of 2-15.
[0029]
In the combination of the organic polymer material, particularly preferable combination is EPDM
as a rubber component, paraffin oil having a kinematic viscosity (100 ° C.) of 5 to 12 mm 2 / S
as a softener, sulfur as a vulcanizing agent, organic foam It is a combination using
azodicarbonamide (ADCA) as an agent.
In addition to zinc oxide, stearic acid, talc as filler, carbon black as reinforcement,
tetramethylthiuram disulfide as vulcanization accelerator, and urea as foaming aid as other
additives in addition to the above components Is particularly preferred.
The combination of such compounding makes it possible to obtain one excellent in molded
vulcanized foam of Mooney viscosity [ML (1 + 4) 100 ° C.] 1 to 30.
[0030]
The speaker edge material of the present invention is manufactured, for example, as follows
using the above-mentioned organic polymer material.
That is, first, the organic polymer material is formed into a sheet (1 to 10 mm in thickness) or a
film (0.1 to 1 mm in thickness). Next, the molded product is placed in a molding die having a
predetermined shape, and is set to an appropriate heating and pressurizing condition, and is
12-05-2019
8
foamed with vulcanization, thereby forming a foam having a structure in which the rubber
component and the softener component are integrated. The speaker edge material which is the
body is manufactured. Alternatively, after the sheet or film is punched into a predetermined
shape, it may be heated and pressed in a mold. Furthermore, the above-mentioned organic
polymer material may be put as it is into a molding die of a predetermined shape and heated and
pressurized.
[0031]
The heating and pressing conditions of the above-mentioned molding die are appropriately set
according to the kind and blending ratio of each component constituting the above-mentioned
organic polymer material, and for example, the temperature 80 to 250 ° C., pressure 0.5 to 6
MPa Preferably, the heat capacity is set to be 0.5 to 5 minutes. Particularly preferably, the heat
capacity is set to a temperature of 150 to 200 ° C., a pressure of 1 to 4 MPa, and a heat
capacity of 1 to 1.5 minutes.
[0032]
Further, in the heat foaming of the organic polymer material, it is preferable to carry out heat
foaming so that the expansion ratio after foaming is 1.05 to 30 times, more preferably 1. in view
of the relationship with the volume of the molding die. 1 to 15 times, particularly preferably 1.5
to 7 times. It is preferable from the viewpoint of the characteristics (acoustic characteristics etc.)
of the speaker edge material that the molding die be filled with an organic polymer material,
heated and foamed and vulcanized so as to obtain such a foaming ratio.
[0033]
And in the speaker edge material obtained, a glass transition temperature will be -45 degrees C
or less. Preferably, the glass transition temperature is -45 to -55 ° C, and generally the lower
limit is -60 ° C. With such properties, it is possible to maintain the function even when used at
low temperatures such as -45 ° C.
[0034]
12-05-2019
9
The glass transition temperature of the above speaker edge material is measured as follows. That
is, a peak point of tan δ which is the following value obtained by measurement under the
condition of a frequency of 1 Hz and a temperature rising rate of 5 ° C./min by a usual general
“ARES” measurement method using a viscoelastic spectrometer The temperature of the glass is
taken as the glass transition temperature.
[0036]
Next, an example will be described together with a comparative example.
[0037]
The components shown below were prepared.
[0038]
[EPDM (1)] Mitsui Chemicals, Inc., EPDM 4021 (Mooney viscosity [ML (1 + 4) 100 ° C]: 24)
[EPDM (2)] Mitsui Chemicals, Inc., EPDM 4010 (Mooney viscosity [ML (1 + 4) ) 100 ° C .: 8)
[Softener (1)] Paraffin oil, manufactured by Idemitsu Kosan Co., Ltd., PW-90 [Kinematic Viscosity
(100 ° C.): 11.25 mm 2 / S] Softener (2)] Paraffin Oil, manufactured by Idemitsu Kosan Co., Ltd.,
PW-32 [Kinematic viscosity (100 ° C.): 5.298 mm 2 / S] [stearic acid] [carbon] manufactured by
Asahi Carbon Co., Ltd. Asahi # 50 [Vulcanization accelerator] Ouchi emerging Noxcella-TT
(foaming agent), manufactured by Chemical Industry Co., Ltd., Biwaru ACLQ (foaming aid),
manufactured by Eiwa Kasei Kogyo Co., Ltd., cell paste K5, manufactured by Eiwa Kasei Kogyo
Co., Ltd.
[1313]
Examples 1 to 3 and Comparative Examples 1 to 3 Each component shown in the following Table
1 was compounded and kneaded at a ratio shown in the same table to prepare an organic
polymer material.
Then, the organic polymer material was formed into a sheet having a thickness of 2 mm.
Then, this was put in a cavity of a molding die for speaker edge, clamped, and foamed and
vulcanized under heating conditions of 200 ° C. for 1 minute to prepare a foam. The notch
12-05-2019
10
portion around the foam was cut to obtain the intended speaker edge.
[0041] Using the foams of the example and comparative examples thus obtained, according to
the method described above, a dynamic viscoelasticity measuring apparatus (viscoelasticity
spectrum meter) [manufactured by Rheometrics, ARES] The glass transition temperature was
measured. That is, it may be measured under the condition of a frequency of 1 Hz and a
temperature raising rate of 5 ° C./min by the “ARES” measurement method (using a jig of a
parallel plate having a sample thickness of about 1.5 mm and a diameter of 7.9 mm). The
temperature at the peak point of the obtained tan δ (= loss modulus / storage modulus) was
taken as the glass transition temperature. Moreover, the said speaker edge was integrated in a
speaker, and the operability test was done in a low temperature environment of -45 degreeC. The
results are shown in Table 2 below.
[0042] [-45.degree. C. Low-Temperature Operation Test] A speaker edge material was
incorporated into a speaker, and continuous reproduction was carried out at -45.degree. C. for 72
hours, and the presence or absence of abnormality of the surface of the edge portion was
observed.
[0043] [Expansion ratio] The density of the foam was calculated by dividing by the specific
gravity of the mixture (organic polymer material).
[0045] As a result of the above Table 2, no abnormality was found in the low temperature
operability test of the example product having a glass transition temperature of -45.degree. C. or
less. On the other hand, the speaker edge material was destroyed in the low temperature
operability test of the comparative example of which the glass transition temperature is higher
than -45 ° C.
[0046] As described above, the speaker edge material of the present invention is formed of an
organic polymer material molded body having a glass transition temperature of -45.degree.
Therefore, even when used for a long time under severe low temperature conditions such as
−45 ° C. as a speaker edge, the function can be maintained without being broken. Therefore,
when the speaker edge material of the present invention is used as a speaker edge, it is possible
to obtain a high quality speaker excellent in acoustic characteristics even under severe use
conditions.
12-05-2019
11
[0047] In particular, an organic polymer material molded body obtained by blending 50 parts or
more of paraffin oil having a kinematic viscosity (100 ° C.) of 5 to 12 mm 2 / S with 100 parts
of ethylene-propylene-terpolymer is used. When it is molded, it has good compatibility with the
above-mentioned ethylene-propylene-terpolymer, and a foamed sheet can be easily obtained at
the time of vulcanization and foaming.
12-05-2019
12
Документ
Категория
Без категории
Просмотров
0
Размер файла
23 Кб
Теги
jp2003244788
1/--страниц
Пожаловаться на содержимое документа