close

Вход

Забыли?

вход по аккаунту

?

JPS642499

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 JPS642499
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a
method of manufacturing a speaker diaphragm molded by an injection molding method, wherein
a speaker diaphragm having a thickness of 0.1 to 0.51 is manufactured by an injection molding
method. The present invention also relates to a method of manufacturing a thin speaker
diaphragm stably by eliminating appearance defects such as flow marks and preventing molding
defects due to insufficient filling such as short shots. [Prior Art] Recently, the speaker diaphragm
is! The composition added to 11 polypropylene resin before filling, such as mica, talc, graphite,
etc., is molded into a sheet in order to increase the rigidity of ropylene-based l @ ポ リ プ ロ ピ レ
ン (polypropylene-based resin), and this sheet is vacuum-formed or compressed. It is molded by a
thermoforming method such as a molding method. However, there is a disadvantage that the
reproduction sound is not true because the light weight and high rigidity characteristics, which
are essential performances for the speaker diaphragm, are insufficient, and the thermoforming
method has a disadvantage: 3m Because it is molded into a temporary shape, thickness
unevenness in the diaphragm original :, F and, for this reason, there is a problem that there is a
problem that 1 harmful form 1 2 · 1 is generated in the speaker diaphragm, 9. To manufacture a
speaker diaphragm by thermoforming a polypropylene resin sheet in which fibers such as glass
fibers and car fibers are mixed instead of flake-like fillers such as mica and talc for the purpose
of further enhancing rigidity. Has been done. This one. In the speaker diaphragm obtained by the
method, the fibers are oriented in one direction of the sheet, so there is a problem that distortion
occurs in the speaker diaphragm after molding. Furthermore, in order to ameliorate these
drawbacks, a method has been proposed for producing a speaker moving plate by injection
molding using a composition obtained by mixing fibrous fillers such as glass fibers and carbon
fibers. (For example, Unexamined-Japanese-Patent No. 57-138300). However, the fibrous filler is
essentially not only difficult to be compatible with the polypropylene resin, but the flowability
11-05-2019
1
also decreases in proportion to the amount of the fibrous filler added. Such a composition has no
particular problem in molding when molding a molded product having a thickness of 2.0 + m * or
more, but has a thickness as thin as a speaker diaphragm (the thickness of the speaker
diaphragm is usually 0.1 to 0, 5 wm) When molding a thin-walled molded article, uneven flow
occurs between the polypropylene resin and the fibrous filler, and a flow mark is generated on
the surface of the molded article, or the entire surface of the molded article The composition
does not spread uniformly, so-called short shot condition, molding failure.
There was a problem that occurs. In order to solve these drawbacks, for example, fatty acids,
metal soaps (for example, metal salts of carboxylic acids) and lubricants such as waxes have been
added, in order to improve the wettability and adhesion between the propylene resin and the
filler. There are widely used methods of using a coupling agent such as a silicon-containing
organic compound and a titanium-containing organic compound, or introducing a reactive group
into the basic resin itself. However, although these methods can improve the effect to some
extent, the improvement effect is not satisfactory, not only technically complicated, but also
economical, health and safety, productivity From the point of improvement, it is an undesirable
method in industrial production. [Problems to be Solved by the Invention] From the above, the
present invention does not have these drawbacks (problems), that is, there is no flow mark on the
surface, and there is no molding failure due to insufficient filling such as short shot. In addition, it
is to obtain a thin speaker imaging plate by a simple method. [Means for Solving the Problems
and Actions] According to the present invention, these problems are (4) modified propylenebased polymers obtained by modifying with unsaturated carboxylic acids and / or their
anhydrides And fibrous fillers or compositions comprising these and propylene-based polymers
[hereinafter referred to as "propylene-based polymers (a)"] io "M part by part" and (B) Melt flow
index (according to JIS K-7210) , The condition is a circle, and a mixture of 5 to 50 parts by
weight of a propylene-based polymer having a concentration of 30 to 100 g (hereinafter referred
to as r MFRJ) [hereinafter referred to as "propylene-based polymer (b)"] And a method of
injection molding the resulting mixture, wherein the composition ratio of the fibrous filler in the
composition is 5 to 50 by weight. It can be solved by the method for manufacturing a speaker
diaphragm. Hereinafter, the present invention will be specifically described. (/ L) Modified
Propylene-Based Polymer The modified propylene-based polymer used to produce the
composition of the present invention comprises a propylene-based polymer (hereinafter referred
to as "propylene-based polymer") described below as an unsaturated carboxylic acid It can be
obtained by denaturation with and / or its anhydride. Representative examples of the
unsaturated carboxylic acid or its anhydride are monobasic carboxylic acids having at most 10
carbon atoms and having at least one double bond (for example, acrylic acid, methacrylic acid)
and carbon Dibasic carboxylic acids (for example, maleic acid) having at most one 15 at least one
double bond and an anhydride of said dibasic carboxylic acid [for example, maleic anhydride, 3,6Endo methylene-1,2,3,6-titrahydrosis-phthalic anhydride].
11-05-2019
2
Of these unsaturated carboxylic acids and anhydrides, maleic acid and maleic anhydride are
particularly preferred. The modified propylene-based polymer is generally prepared by melting
propylene-based polymer (C) in the presence of a radical initiator, unsaturated carboxylic acid
and / or an anhydride thereof by various known methods (eg, solution method, suspension
method, melting) Can be processed by any method of Among these methods, in particular, the
melting method is industrially preferable. As a radical initiator, 2,5-dimethyl-2,5-di (tert-butyl tJ?
And organic peroxides such as -oxy) hexane, 2.5-dimethyl-2,5- (tert-butyl-9-oxy) hexyne-3 and
benzoyl peroxide. In the case of production by a melting method, a propylene-based polymer
Takao unsaturated carlic acid and / or an anhydride thereof and the above-mentioned are
produced using a melt mixing machine (for example, an extruder) used in the field of general
synthetic resins. The radical order agent of the present invention can be obtained by processing
while melting and kneading. The mixed wire temperature in this case varies depending on the
type of g-pyrene-based polymer weight and radical ordering agent used, but it is a temperature
range from the melting point of the propylene-based polymer chamber to 300 ° C. or less. 270
° C. is preferred. (B) Propylene-based polymer A propylene-based polymer (c) used for
producing the modified propylene-based polymer, a propylene-based polymer (a) used for
producing the composition, and a speaker diaphragm The propylene polymers (b) used in the
production may be all propylene homopolymers, and a small amount of propylene (generally at
most 25% by weight, preferably 20! i% or less. Preferably, 0.1 to 15] [% by weight] of ethylene
and / or at most 12 (preferably 4 to 8) α-olefins (eg, butene-1,4-methylpentene) having carbon
number of at most 12 It may be a random or block copolymer with -1, hexene-1). The MFR of the
propylene-based polymer (a) and the propylene-based polymer (c) is usually 0.1 to 3 (1/10
minutes, preferably 0.2 to 30 g / 10 minutes, and particularly preferably 0.2 to 25 g / hour). 10
minutes is preferred. If propylene polymers having an iFR of less than 0.1 g / 10 min are used as
these propylene polymers, the moldability of the composition of the present invention is not
good. On the other hand, when using a propylene-based polymer exceeding 30 g 710 minutes,
the impact resistance is not good.
The MFR of propylene-based 1-copolymer (b) is 30 to 100.9 / 10 minutes, preferably 35 to
1009/10 minutes, and particularly preferably 40 to 100 g 710 minutes. If a propylene-based
polymer having an MFR of less than 30 g / 10 min is used as the propylene-based polymer (b),
the moldability is inferior. On the other hand, when using a propylene-based polymer exceeding
100 g / 10 min, the mechanical properties are not good. All of these modified propylene
polymers and propylene polymers are industrially produced and widely used, and their
production methods are well known. C) Fibrous filler Furthermore, the fibrous filler used in the
present invention has a diameter of 1 to 500 μm (preferably, 1 to 300 μm) and a length of 0.1
to 10 mm (preferably, 0) .2 to 10 m1) is preferable. As these fibrous fillings 4], glass fibers and
cardan fibers can be mentioned. (0 Composition Ratio The composition ratio of the fibrous filler
in the composition of the present invention is 5 to 50, preferably 5 to 45, and particularly
11-05-2019
3
preferably 5 to 40. If the composition ratio of the fibrous filler in the composition is less than 5%
by weight, a speaker diaphragm having excellent rigidity can not be obtained. On the other hand,
when it exceeds 50 N M%, a flow mark occurs on the speaker diaphragm obtained by shaping the
mixture. In the present invention, the ratio of the unsaturated carboxylic acid and the anhydride
thereof used for producing the modified propylene polymer in the total of 1100 g of the
modified propylene polymer and the propylene group 1 copolymer (a) is 10 to 10 millimoles
(preferably Is preferably 2 × 10 5 millimoles, preferably 5 × 10 2 millimoles). (Production of
Composition In order to produce the composition of the present invention, the modified
zolopylene polymer and the fibrous filler, or these and the propylene polymer (a) are usually
sunk so as to be even. You can apply the method. The methods are a method of tri-blending using
a mixer such as a Henschel mixer and a method of melt-kneading using a mixer such as Banbury
mixer, Niegoo, roll mill and screw extruder. At this time, a more uniform composition can be
obtained by triblending in advance and further melt-kneading the resulting mixture. In this case,
generally, after melt-kneading, it is formed into a pellet and used for the production of a molded
product described later.
Although the composition of the present invention can be obtained so as to make each of the
above composition components uniform within the above composition ratio range, stabilizers for
heat, oxygen and light, metal deterioration inhibitors, electrical characteristics Additives such as
modifiers, adhesion improvers, flame retardants, blowing agents, lubricants, plasticizers and
colorants may be incorporated. (G) Production of mixture A mixture can be produced by mixing
the composition obtained as described above and the zolopylene polymer (b) without kneading.
Furthermore, instead of the propylene-based polymer (b), a part or all of the above-described
modified propylene-based polymer may be used. In producing the mixture of the present
invention, the proportion of the propylene-based polymer (b) to 100 parts by weight of the
composition is 5 to 50 parts by weight, preferably 5 to 40 parts by weight, and 9 to 7 parts by
weight Is preferred. If the proportion of the zolopylene polymer (b) to the composition of 100
parts by weight is less than 5% by weight, the improvement effect is not observed. On the other
hand, if it exceeds 50 parts by weight, the improvement effect is sufficiently recognized, but the
ratio of the fibrous filler occupied in the mixture is significantly reduced, and the initial purpose
is to further alter its physical properties. Can not achieve. The amount of the fibrous filler in the
mixture obtained from the composition and the propylene-based polymer (b) is preferably 3 to
35 volumes, and more preferably 5 to 30 volumes. When the mixture is melt-kneaded with the
composition and the zolopyrene polymer (b), a speaker diaphragm having a good appearance
such as a flow mark can not be obtained. That is, it is necessary to tri-blend them. Even if it is
made to melt and knead, the speaker diaphragm which exhibits the object of the present
invention can not be obtained. The thus obtained mixture can be molded into a molded product
by a commonly used injection molding method. At this time, the propylene polymer (b) mixed
with the composition may contain additives other than the filler mixed in the composition. In
addition, stabilizers are usually required to be blended. (F ′) Production of Speaker Diaphragm
11-05-2019
4
The loudspeaker diaphragm of the present invention can be produced by the injection molding
method generally practiced in the field of olefin resins, for the mixture thus obtained. Whether
melt-kneaded at the time of producing the composition or injection-molded at the time of
producing the speaker diaphragm, it must be carried out at a temperature above the melting
point of the propylene polymer or its modified product used. However, when it is carried out at a
temperature of 350 ° C. or higher, it is possible that a part of the propylene-based polymer or
its modified product causes thermal degradation.
Therefore, it is natural that it must be carried out below this temperature. EXAMPLES AND
COMPARATIVE EXAMPLES The present invention will be further described in detail by the
following examples. Example 1 Propylene homopolymer (MFR 1, 09/10 minutes at a ratio of
0.9009 / crn 3 as a propylene polymer (C), hereinafter referred to as [PP (a) J]), 100 parts by
weight, 0, 01 Parts by weight of 2,5-dimethyl-2,5-so (butylperoxy) hexane (as a peroxidic
peroxide) and maleic anhydride were previously triblended for 5 minutes using a Henschel mixer.
The resulting mixture was melt-kneaded using an extruder (diameter 40, resin temperature 220
° C.) to prepare modified polypropylene [hereinafter referred to as modified PP (1) J]. The
modified pp (maleic anhydride content in the bottle was related to 0.6 by weight. 70 parts by
weight of the modified PP (1) and 30 parts by weight of carbon fiber as fibrous filler (average
diameter 7 μm, length 6 throat, hereinafter referred to as r CF J) are mixed for 3 minutes using
a Henschel mixer ( Tri-blend) friend. The obtained mixture was pelletized while being meltkneaded (vent suction (600 ° -Hg), resin temperature 200 ° C.) using a twin-screw pendent
extruder (diameter 30 m). Add 20 parts by weight of a propylene homopolymer (MFR 40 g 710
minutes, hereinafter referred to as rPP (d) as a propylene-based polymer (b)) to 100 parts by
weight of this pellet, and mix for 100 minutes using a tumbler ( Tri-blend). The mixture obtained
was used with an injection molding machine with a clamping pressure of 100 tons (resin
temperature 280 ° C.) Speaker diaphragm (thickness 0.4 mm, top surface diameter 150 square,
bottom surface diameter 4 C) + m, height 35 tuning Was molded. As a result, the molded product
was free of flow marks, and a beautiful product was obtained over the entire surface.
Comparative Example 1 A speaker imaging plate was molded in the same manner as in Example
1 except that P P (d) used in Example 1 was not mixed. However, only the gate portion (lower
surface portion) of the mold of the speaker moving plate could not be molded since the resin
flowed in. Example 2 Modified PP (1) 103 Um used in Example 1: 60 parts by weight of a
propylene homopolymer having a density of 0.90097 cm 3 and an MFR of 209710 minutes and
the CF 30 M loading portion as Example 1 Tri-blending and mixing were carried out in the same
manner as above to prepare a composition. 100 parts by weight of this composition and 20 parts
by weight of the above Pp (d) were subjected to tri-blending in the same manner as in Example 1
to manufacture a mixture.
The obtained mixture was injection molded in the same manner as in Example 1 to produce a
11-05-2019
5
speaker diaphragm. EXAMPLE 3 Instead of the modified PP (1) used in Example 2, the density is
0.90097 cm 3 and the MFR is 1. Modified propylene homopolymer (hereinafter referred to as
"modified PP (2) J") prepared by the same method as in the preparation of the modified PP (1) of
Example 1 for the propylene homopolymer having og 710 minutes [the same amount (10
weight)] The composition was prepared by tri-blending and kneading under the same conditions
as in Example 2 except that part (A) was used. 100 parts by weight of this composition, a
propylene-ethylene block copolymer having a density of 0.9009 / cm 3, and an MFR of 609/10
min [Copolymerization of ethylene: 8.0 wt%, c) 20 parts by weight of J was subjected to triblending in the same manner as in Example 2 to produce a mixture. The obtained mixture was
injection molded in the same manner as in Example 2 to produce a speaker diaphragm. Example
4 A composition was prepared in the same manner as in Example 3 except that glass fibers
having an average length of 6 rta and an average diameter of 13 μm were used in place of CF in
Example 3. Made things. Tri-blending was carried out in the same manner as in Example 3 except
that this obtained mixture was used instead of the composition used in Example 3, and the
resulting mixture was injection-molded in the same manner as in Example 3 to give a speaker I
made a moving plate. Example 5 A mixture was produced in the same manner as in Example 3,
except that the amount of PP (c) used in producing the mixture in Example 3 was changed to 1
ON part. The resulting mixture was injection molded in the same manner as in Example 3 to
produce a speaker diaphragm. Comparative Example 2 Instead of p p (d) used in preparing the
mixture in Example 2, the same! A mixture was produced in the same manner as in Example 2
except that PP (a) (the one used for producing the modified propylene polymer (1) used in
Example 1) (20 N fingers) was used. The obtained mixture was injection-molded in the same
manner as in Example 2 to produce a speaker diaphragm. Comparative Example 3 A mixture was
produced in the same manner as in Example 2 except that the amount of P P (d) used in
producing the mixture in Example 2 was changed to 60 i parts. The resulting mixture was
injection molded in the same manner as in Example 2 to produce a speaker diaphragm.
Comparative Example 4 Tri-blend under the same conditions as in Example 2 except that in
preparing the composition in Example 2, the same amount (20 parts by weight) of P P (d) used in
preparation of the mixture was further blended. The mixture was kneaded to produce a
composition.
In the same manner as in Example 2 except that the composition obtained as described above
was used instead of the mixture used in manufacturing the speaker diaphragm, a speaker
imaging plate was manufactured. Comparative Example 5 A sheet having a thickness of 0.4 mm
was prepared using a T-gui molding machine, comprising a composition comprising 70 parts by
weight of PP (a) and 30 parts by weight of mica having an average particle diameter of 8 μm .
The obtained sheet was used to manufacture a speaker imaging plate by a vacuum forming
method. The occurrence of flow marks was not observed on the surface of the speaker
diaphragms obtained in Examples 2 to 5 and Comparative Example 3, and the entire surface was
beautiful. However, in each of the speaker diaphragms obtained by Comparative Example 2 and
11-05-2019
6
Comparative Example 4, a flow mark was generated on the surface. Each speaker diaphragm
obtained in Example 1, Comparative Example 3 and Comparative Example 5 was incorporated
into a speaker, and the frequency characteristics were measured in an anechoic chamber. The
results are shown in FIG. In the drawing, the vertical axis is the output sound pressure level (dB),
and the horizontal axis is the frequency (hertz). Curve A represents the frequency characteristics
of the speaker diaphragm obtained in Example 1, curve B represents the speaker moving plate
obtained in Comparative Example 5, and curve @C represents the frequency characteristics of the
speaker diaphragm obtained in Comparative Example 3. It is a curve. The speaker diaphragm
obtained by the method of the present invention exhibits the following effects. (1) There is no
flow mark on the surface and it is beautiful. (2) There is no molding failure due to insufficient
filling such as short shot. (3) The frequency curve is flat in the high frequency range, there is no
extension of sound in the middle to high range, there is little noise, and the separation and
reproduction effects are excellent.
[0002]
Brief description of the drawings
[0003]
FIG. 1 shows the vibration characteristics of each speaker diaphragm obtained in Example 1,
Comparative Example 3 and Comparative Example 5.
11-05-2019
7
Документ
Категория
Без категории
Просмотров
0
Размер файла
19 Кб
Теги
jps642499
1/--страниц
Пожаловаться на содержимое документа