close

Вход

Забыли?

вход по аккаунту

?

JP2005094270

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 JP2005094270
PROBLEM TO BE SOLVED: To provide a film forming material used for a speaker diaphragm
which can exhibit excellent waterproof performance over a long period of time and can suppress
deterioration of sound quality. SOLUTION: A film forming material used to form a film for
covering the surface of a speaker diaphragm comprises a fluorine-containing polymer segment
formed of a fluorine-containing monomer and a single amount containing no fluorine. It is
comprised by the fluorine-containing block copolymer which consists of a non-fluorinated
polymer segment formed from the body. The fluorine-containing polymer segment is preferably
formed of a fluorine-containing monomer alone or a mixture of a fluorine-containing monomer
and an alkyl (meth) acrylate having 12 to 22 carbon atoms in the alkyl group. The fluorinecontaining block copolymer is preferably produced by a two-step polymerization method using a
polymeric peroxide as a polymerization initiator. [Selected figure] None
Coating material
[0001]
The present invention relates to a film forming material used to form a film that covers the
surface of a speaker diaphragm used in various acoustic devices.
[0002]
In recent years, a diaphragm used for an on-vehicle door mount speaker or the like is subjected
to waterproofing treatment because raindrops are applied when the door is opened or closed.
11-05-2019
1
As this waterproofing process, for example, at a raw material stage before making paper of a
paper pulp diaphragm, a waterproof resin diaphragm is formed by fixing a synthetic resin having
a fluorine group at the end to paper pulp and paper-forming this raw material. It is proposed (for
example, refer patent document 1).
[0003]
In addition, at the raw material stage before papermaking of a diaphragm made of paper pulp, a
synthetic resin having a fluorine group at the end is fixed to paper pulp, and this raw material is
made into paper and thermoformed in an organic solvent solution of another synthetic resin. A
diaphragm for waterproof type speaker is proposed, in which a synthetic resin layer is formed on
the surface by immersing in a water-proof type (see, for example, Patent Document 2).
Furthermore, a waterproof speaker diaphragm in which a water repellent paint is applied to a
diaphragm that has not been waterproofed has been proposed (see, for example, Patent
Document 3). JP-A-5-183985 (page 2) JP-A-5-328887 (page 2) JP-A 2000-138987 (page 2)
[0004]
However, the speaker diaphragm described in the above-mentioned conventional patent
document 1 is made by making paper pulp on which a synthetic resin having a fluorine group at
its end is fixed, and the synthetic resin having a fluorine group at the terminal is fluorine Only
the part where the group was oriented on the surface could only exert its waterproof effect.
Therefore, the waterproofing effect was low. The speaker diaphragm described in Patent
Document 2 is formed by forming a synthetic resin layer on the surface of a paper sheet of paper
pulp on which a synthetic resin having a fluorine group at the end is fixed. Since the fluorine
group oriented to is covered by the synthetic resin layer, the function could not be exhibited.
Furthermore, since a polyester synthetic resin is specifically used as a synthetic resin which
forms the synthetic resin layer, there existed a problem that such resin can not exhibit sufficient
waterproof performance.
[0005]
In addition, although the speaker diaphragm described in Patent Document 3 has a surface
coated with a water-repellent paint, the general water-repellent paint can exhibit a certain level
11-05-2019
2
of water-repellent performance, but it vibrates. There is a problem that the waterproof
performance can not be maintained for a long time because of the lack of adhesion to the board.
When the waterproof performance is lowered, the diaphragm is infiltrated with water, so that the
diaphragm can not be vibrated sufficiently and there is a problem that the sound quality tends to
be deteriorated.
[0006]
The present invention has been made in view of the problems existing in such prior art. An object
of the present invention is to provide a film forming material used for a speaker diaphragm
which can exhibit excellent waterproof performance over a long period of time and can suppress
deterioration of sound quality.
[0007]
In order to achieve the above object, the film-forming material of the first invention comprises a
fluorine-containing polymer segment formed from a fluorine-containing monomer and a nonfluorine formed from a fluorine-free monomer It is characterized in that it is made of a fluorinecontaining block copolymer consisting of a polymer segment, and is used to form a film that
covers the surface of the speaker diaphragm.
[0008]
The film-forming material of the second invention is the film-forming material of the first
invention, wherein the fluorine-containing polymer segment of the fluorine-containing block
copolymer is a fluorine-containing monomer alone or a fluorine-containing monomer and an
alkyl group. It is characterized in that it is formed from a mixture with a C12-22 alkyl (meth)
acrylate.
[0009]
The film-forming material of the third invention is characterized in that, in the first or second
invention, the fluorine-containing monomer is a monomer represented by the following general
formula (A): It is a thing.
(A): R <f> -R <1> OOCCR <2> = CH 2 (where R <f> is a fluoroalkyl group or fluoroalkenyl group
11-05-2019
3
having 3 to 21 carbon atoms, R <1> is 1 to 10 carbon atoms An alkylene group, R <2> is
hydrogen or a methyl group.
The film-forming material of the fourth invention is any one of the first to third inventions,
wherein the fluorine-containing block copolymer contains a fluorine-free monomer and a
plurality of peroxy bonds in one molecule. The polymerization is carried out using a polymer
peroxide having the formula as a polymerization initiator to obtain a peroxy bond-containing
polymer, and then a monomer containing fluorine is added to form a polymer, or a monomer
containing fluorine is formed. A polymer obtained by performing polymerization using the abovedescribed polymeric peroxide as a polymerization initiator to obtain a peroxy bond-containing
polymer, and then adding a monomer not containing fluorine to perform polymerization; It is.
[0010]
According to the film-forming material of the first aspect of the invention, the film covering the
surface of the speaker diaphragm can exhibit excellent waterproof performance over a long
period of time, and can suppress deterioration in the sound quality of the speaker.
[0011]
According to the film forming material of the second invention, in addition to the effect of the
first invention, the waterproof performance of the film can be improved.
According to the film-forming material of the third invention, in addition to the effects of the first
or second invention, the polymerization conversion for obtaining the fluorine-containing block
copolymer can be increased, and the waterproof performance of the film can be improved. It can
be improved.
[0012]
According to the film-forming material of the fourth invention, in addition to the effects of any
one of the first to third inventions, the yield of the fluorine-containing block copolymer can be
improved, and the fluorine-containing block copolymer can be obtained. The production of the
united body can be easily performed.
[0013]
11-05-2019
4
Hereinafter, embodiments of the present invention will be described in detail.
The film-forming material of the present embodiment is used to form a film for covering the
surface of the speaker diaphragm, and contains a fluorine-containing polymer segment formed of
a fluorine-containing monomer, and fluorine. It is comprised by the fluorine-containing block
copolymer which consists of a non-fluorinated polymer segment formed from the monomer
which is not.
[0014]
First, the fluorine-containing polymer segment constituting one molecular chain of the block
copolymer will be described. The fluorine-containing polymer segment refers to a monomer
containing a fluorine atom (also referred to simply as fluorine in the present patent), that is, a
polymer portion formed by polymerizing a fluorine-containing monomer. The fluorine-containing
polymer segment is a fluorine-containing monomer alone or a fluorine-containing monomer and
an alkyl acrylate or alkyl methacrylate having 12 to 22 carbon atoms in the alkyl group
(generally referred to as alkyl (meth) acrylate in this patent) Preferably formed from a mixture of
When the fluorine-containing polymer segment is formed solely of a fluorine-containing
monomer, the content of fluorine in the fluorine-containing polymer segment is increased, so that
the waterproof performance of the film can be improved. When the fluorine-containing polymer
segment is formed of a mixture of a fluorine-containing monomer and an alkyl (meth) acrylate
having 12 to 22 carbon atoms in length of alkyl chain, lowering the crystal formation
temperature of the fluoroalkyl group Even when the film is formed by drying at a temperature
close to normal temperature, the waterproof performance of the film can be exhibited.
[0015]
As the fluorine-containing monomer, one or more kinds of known fluorine-containing monomers
can be used. For example, the fluorine-containing monomer represented by general formula (G)
from the following general formula (A) is mentioned. (R <f> is a polyfluoroalkyl group or
polyfluoroalkenyl group having 3 to 21 carbon atoms, R <1> is an alkylene group having 1 to 10
carbon atoms, R <2> is hydrogen or a methyl group, R <3> Is hydrogen or an alkyl group having
1 to 10 carbon atoms, and Ar is an aryl group which may have a substituent. As Ar), a phenyl
group, a tolyl group and the like can be mentioned.
11-05-2019
5
(A):R<f>−R<1>OOCCR<2>=CH2
(B):R<f>−SO2(R<3>)NR<1>OOCCR<2>=CH2
(C):R<f>−CO(R<3>)NR<1>OOCCR<2>=CH2
(D):R<f>−CH2C(OH)HCH2OOCCR<2>=CH2
(E):R<f>−CH2C(OCOR<3>)HCH2OOCCR<2>=CH2
(F):R<f>−O−Ar−CH2OOCCR<2>=CH2
[0016]
<img class = "EMIRef" id = "199026167-00002" /> Specific examples of the monomer
represented by the general formula (A) are shown by the following (a-1) to (a-12) Monomers are
included. F (CF2) 6 (CH2) 2OCOCH = CH2 (a-1) F (CF2) 8 (CH2) 2OCOCH = CH2 (a-2) F (CF2) 10
(CH2) 2OCOCH = CH2 (a-3) H ( CF2) 8CH2OCOCH = CH2 (a-4) (CF3) 2CF (CF2) 6 (CH2) 2OCOCH
= CH2 (a-5) (CF3) 2CF (CF2) 8 (CH2) 2OCOCH = CH2 (a-6) F ( CF2) 6 (CH2) 2OCOC (CH3) = CH2
(a-7) F (CF2) 8 (CH2) 2OCOC (CH3) = CH2 (a-8) F (CF2) 10 (CH2) 2OCOC (CH3) = CH2 (a-9) H
(CF2) 8CH2OCOC (CH3) = CH2 (a-10) (CF3) 2CF (CF2) 6 (CH2) 2OCOC (CH3) = CH2 (a-11) (CF3)
2CF (CF2) 8 (CH2) 2OCOC (CH3) = C Specific examples of the monomer represented by 2 (a-12)
Formula (B), a monomer and the like represented by the following (b-1) ~ (b-7). F (CF2) 8SO2N
(CH3) CH2CH2OCOCH = CH2 (b-1) F (CF2) 8SO2N (CH3) (CH2) 4OCOCH = CH2 (b-2) F (CF2)
8SO2N (CH3) (CH2) 10OCOCH = CH2 ( b-3) F (CF2) 3SO2N (C2H5) C (CH2CH3) HCH2OCOCH =
CH2 (b-4) F (CF2) 8SO2N (CH3) CH2CH2OCOC (CH3) = CH2 (b-5) F (CF2) 3SO2N (C2H5 )
CH2CH2OCOC (CH3) = CH2 (b-6) F (CF2) 3SO2N (C3H7) CH2CH2OCOC (CH3) = CH2 (b-7) As a
specific example of the monomer represented by the general formula (C), Monomers represented
by (c-1) to (c-4) can be mentioned. F (CF2) 2CON (C2H5) CH2OCOCH = CH2 (c-1) F (CF2) 3CON
(CH3) CH (CH3) CH2OCOCH = CH2 (c-2) F (CF2) 8CON (CH2CH2CH3) CH2CH2OCOC (CH3) =
CH2 (c-3) F (CF2) 8CON (C2H5) CH2OCOC (CH3) = CH2 (c-4) As specific examples of the
monomer represented by Formula (D), the following (d-1) to (d) The monomer shown by d-4) is
mentioned.
F (CF2) 8CH2CH (OH) CH2OCOCH = CH2 (d-1) (CF3) 2CF (CF2) 2CH2CH (OH) CH2OCOCH =
CH2 (d-2) F (CF2) 8CH2CH (OH) CH2OCOC (CH3) = CH2 (CH2) d-3) (CF3) 2CF (CF2) 2CH2CH
(OH) CH2OCOC (CH3) = CH2 (d-4) As a specific example of the monomer represented by the
general formula (E), the following (e-1) And monomers shown by (e-2). (CF3) 2CF (CH2) 6CH2CH
(OCOCH3) CH2OCOCH = CH2 (e-1) (CF3) 2CF (CH2) 6CH2CH (OCOCH3) CH2OCOC (CH3) = CH2
(e-2) represented by the general formula (F) As a specific example of a monomer, the monomer
shown by the following (f-1)-(f-4) is mentioned.
11-05-2019
6
[0017]
<img class = "EMIRef" id = "199026167-00003" />
[0018]
<img class = "EMIRef" id = "199026167-00004" />
[0019]
<img class = "EMIRef" id = "199026167-000005" />
[0020]
<img class = "EMIRef" id = "199026167-000006" /> Specific examples of the monomer
represented by the general formula (G) include monomers represented by (g-1) below.
[0021]
<img class = "EMIRef" id = "199026167-000007" /> In the above general formulas (A) to (G), R
<f> is a polyfluoroalkyl group having 3 to 21 carbon atoms or a polyfluoroalkenyl group Among
them, a polyfluoroalkyl group having 6 to 10 carbon atoms or a polyfluoroalkenyl group is more
preferable.
When the carbon number of R <f> is 2 or less, the waterproof performance of the film tends to
decrease, and when the carbon number is 22 or more, the polymerization conversion for
obtaining a block copolymer decreases because the long chain has a considerable length. There is
a tendency.
Further, R <1> is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an
alkylene group having 1 to 4 carbon atoms.
When the number of carbon atoms exceeds 10, long chains are formed, and therefore the
polymerization conversion ratio for obtaining a block copolymer tends to decrease.
Furthermore, R <2> is hydrogen or a methyl group.
11-05-2019
7
[0022]
Among the fluorine-containing monomers represented by the general formulas (A) to (G), the
fluorine-containing monomer represented by the general formula (A) is excellent in waterproof
performance and polymerization conversion rate. This is because the fluorine-containing
monomer represented by the general formula (A) is excellent in the crystallinity and the surface
orientation based on the fluoroalkyl group. Furthermore, the following monomers are mentioned
as a specific example of a fluorine-containing monomer especially preferable in the fluorinecontaining monomer represented by General formula (A). F (CF2) 8 (CH2) 2OCOCH = CH2 (a-2) F
(CF2) 8 (CH2) 2OCOC (CH3) = CH2 (a-8) (CF3) 2CF (CF2) 6 (CH2) 2OCOCH = CH2 ( a-5) (CF3)
2CF (CF2) 6 (CH2) 2OCOC (CH3) = CH2 (a-11) Fluorine-containing unit other than the monomers
represented by the above general formulas (A) to (G) The following monomers are mentioned as
a body. F (CF2) 6 CH 2 OCH = CH 2 F (CF 2) 8 CH 2 OCH = CH 2 F (CF 2) 10 CH 2 OCH = CH 2 F
(CF 2) 6 CH 2 O CF = CF 2 F (CF 2) 8 CH 2 O CF = CF 2 F (CF 2) 10 CH 2 O CF = CF 2 F (CF 2) 6
CH = CH 2 F (CF2) 8 CH = CH2 F (CF2) 10 CH = CH2 F (CF2) 6 CF = CF2 F (CF2) 8 CF = CF2 F
(CF2) 10 CF = CF2 CH2 = CF2 CF2 = CFCl CF2 = CF2 Fluorinated polymer segment Examples of
the alkyl (meth) acrylate having 12 to 22 carbon atoms in the alkyl group which is
copolymerized with the fluorine-containing monomer for formation include, for example, lauryl
(meth) acrylate, dodecyl (meth) acrylate, (meth) Tridecyl acrylate, (Meth) acre Le acid tetradecyl,
(meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, stearyl (meth) isostearyl
acrylate, behenyl (meth) acrylate and the like are suitably used. In order to further enhance the
waterproof performance of the film, hexadecyl (meth) acrylate, stearyl (meth) acrylate, isostearyl
(meth) acrylate, behenyl (meth) acrylate and the like are preferable. One or more of these
monomers may be selected and used according to the purpose.
[0023]
As described above, by copolymerizing an alkyl (meth) acrylate having 12 to 22 carbon atoms in
the alkyl group, excellent waterproof performance can be exhibited. The main reason is that the
crystal formation temperature of the fluoroalkyl group in the fluorine-containing monomer is 30
to 30 by the copolymerization of the fluorine-containing monomer and the alkyl (meth) acrylate
having 12 to 22 carbon atoms of the alkyl group. It drops to 40 ° C. For this reason, the
waterproof performance developed by the crystal formation of the fluoroalkyl group can be
exhibited at around room temperature. Therefore, it is particularly effective when drying at
normal temperature, and even in that case, the waterproof performance of the film can be
sufficiently exhibited.
11-05-2019
8
[0024]
The ratio of the fluorine-containing monomer to the alkyl (meth) acrylate having 12 to 22 carbon
atoms of the alkyl group is preferably 100/0 to 20/80, more preferably 100/0 to 40/60 by mass
ratio. is there. If the proportion of the fluorine-containing monomer is less than 20/80, the
waterproof performance tends to be lowered since the crystal formation of the fluoroalkyl group
is insufficient.
[0025]
Next, the non-fluorinated polymer segment that constitutes the other molecular chain of the
block copolymer will be described. A non-fluorinated polymer segment refers to a polymer
portion formed by polymerizing a non-fluorinated monomer that does not contain a fluorine
atom. This non-fluorinated polymer segment exhibits a good affinity to the speaker diaphragm
made of paper or the like, and contributes to the adhesion. Therefore, as a monomer which forms
a non-fluorinated polymer segment, the monomer which can exhibit such a function more
effectively is selected and used.
[0026]
Specific examples of the monomer forming the non-fluorinated polymer segment include methyl
(meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, Lower
alkyl (meth) acrylates such as glycidyl (meth) acrylate; n-butyl (meth) acrylate, i-butyl (meth)
acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate And higher alkyl (meth) acrylates such as
cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth)
acrylate and stearyl (meth) acrylate; vinyl acetate, propionone Lower fatty acid vinyl esters such
as acids; vinyl caproate, vinyl 2-ethylhexanoate, laurin Higher fatty acid vinyl esters such as vinyl
and vinyl stearate; aromatic vinyl type monomers such as styrene, vinyl toluene and vinyl
pyrrolidone; (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth)
acrylamide An amide group-containing vinyl-type monomer such as N, N-dimethyl (meth)
acrylamide; a hydroxyl-containing vinyl-type monomer such as hydroxyethyl (meth) acrylate or
hydroxypropyl (meth) acrylate; (meth) acrylic Carboxylic acid group-containing vinyl monomers
such as acid, itaconic acid, crotonic acid, fumaric acid, and maleic acid; butadiene; vinyl chloride;
vinylidene chloride; (meth) acrylonitrile; dibutyl fumarate; maleic anhydride; (Meth) acrylic acid,
11-05-2019
9
crotonic acid and other radically polymerizable unsaturated Alkali metal salts of carboxylic acids,
ammonium salts, organic amine salts, organic amine salts; radically polymerizable unsaturated
monomers having a sulfonic acid group such as styrene sulfonic acid, and alkali metal salts
thereof, ammonium salts, organic amines Salts, organic amine salts; quaternary ammonium salts
derived from (meth) acrylic acid such as 2-hydroxy-3-methacryloxypropyl trimethyl ammonium
chloride; dimethylaminoethyl (meth) acrylate, (meth) acrylic acid And (meth) acrylic acid esters of
alcohols having a tertiary amino group such as diethylaminoethyl, and quaternary ammonium
salts thereof. One or two or more of these monomers are appropriately selected and used.
[0027]
Among the above non-fluorinated monomers, the following monomers are used as preferable
monomers from the viewpoint of good adhesion to the base material, that is, the diaphragm for a
speaker and the polymerization conversion rate. As such non-fluorine monomers, methyl (meth)
acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, glycidyl (meth)
acrylate, (Meth) acrylic acid n-butyl, (meth) acrylic acid i-butyl, (meth) acrylic acid t-butyl, (meth)
acrylic acid n-hexyl, styrene, vinyl toluene, vinyl pyrrolidone, (meth) acrylic acid hydroxy Ethyl,
hydroxypropyl (meth) acrylate, (meth) acrylic acid, alkali metal salts of ammonium (meth) acrylic
acid, ammonium salts, organic amine salts, organic amine salts, 2-hydroxy-3-methacryloxypropyl
trimethyl ammonium chloride, etc. Can be mentioned.
[0028]
The ratio of the fluorine-containing polymer segment to the non-fluorinated polymer segment in
the fluorine-containing block copolymer is preferably 10/90 to 80/20 by mass ratio, and more
preferably 20/80 to 70/30. . If the fluoropolymer segment is less than 10/90, the arrangement
of perfluoroalkyl groups tends to be insufficient and the waterproof performance tends to be
insufficient. On the other hand, when the fluoropolymer segment exceeds 80/20, the nonfluoropolymer segment decreases, and the adhesion to the base material tends to decrease.
[0029]
Next, the method for producing the fluorine-containing block copolymer will be described. This
production method is preferably based on a two-step polymerization method comprising a first
step and a second step from the viewpoint of the polymerization yield of the fluorine-containing
11-05-2019
10
block copolymer, the simplicity of production and the like. In the first step, a non-fluorinated
monomer forming a non-fluorinated polymer segment is polymerized using a polymeric peroxide
as a polymerization initiator to obtain a peroxy bond-containing polymer. Next, in the second
step, using the obtained peroxy bond-containing polymer as a polymerization initiator, a fluorinecontaining monomer, or a fluorine-containing monomer and an alkyl (meth) acrylate having 12
to 22 carbon atoms in the alkyl chain length And polymerize the mixture with to form a
fluoropolymer segment. In the above two-stage polymerization, the non-fluorinated monomer in
the first step may be used in the second step, and the fluorinated monomer in the second step
may be used in the first step.
[0030]
This polymerization method is produced by a known production process (for example, described
in Japanese Patent Publication No. 5-41668 and Japanese Patent Publication 5-59942). The
polymeric peroxide used at the time of manufacture of the said fluorine-containing block
copolymer means the compound which has a several peroxy bond in 1 molecule. As the
polymeric peroxide, one or more of various polymeric peroxides described in JP-B-5-59942 can
be used.
[0031]
For example, those represented by the following general formulas (1) to (3) can be used.
[0032]
<img class = "EMIRef" id = "199026167-000008" />
[0033]
<img class = "EMIRef" id = "199026167-000099" />
[0034]
<img class = "EMIRef" id = "199026167-000010" /> In the general formulas (1) to (3), n is an
integer of 2 to 20.
[0035]
11-05-2019
11
The fluorine-containing block copolymer can be easily obtained by solution polymerization, bulk
polymerization, suspension polymerization or emulsion polymerization using the abovementioned polymeric peroxide.
For example, in the case of the solution polymerization method, a non-fluorinated polymer
segment is formed as a fluorinated block copolymer in the first step, and a fluoropolymer
segment is formed in the second step as an example. be able to.
[0036]
That is, a non-fluorinated polymer containing a peroxy bond in which a peroxy bond is
introduced in the chain is obtained by first using a polymeric peroxide as a polymerization
initiator in the first step and polymerizing a non-fluorinated monomer in a solution. can get.
Next, in the second step, when a fluorine-containing monomer is added to the solution produced
in the first step to carry out the polymerization, the peroxy bond in the non-fluorine polymer
containing a peroxy bond is cleaved to efficiently carry out the fluorine-containing A block
copolymer is obtained.
The amount of use of the polymeric peroxide used in the first step in the production of the
fluorine-containing block copolymer is usually 0.5 to 20 parts by mass with respect to 100 parts
by mass of the monomer used in the first step, The polymerization temperature is 40 to 130 °
C., and the polymerization time is about 2 to 12 hours.
The polymerization temperature in the second step is usually 40 to 140 ° C., and the
polymerization time is about 3 to 15 hours.
[0037]
The obtained fluorine-containing block copolymer can be used as one obtained by dissolving or
dispersing in a solvent shown below, or one obtained by dispersing a surfactant or the like and
dispersing it in water for emulsification. Furthermore, fine powders of the fluorine-containing
11-05-2019
12
block copolymer can also be added directly to conventional fluorine-based paints. The molecular
weight of the fluorine-containing block copolymer is preferably 1,000 to 500,000, and more
preferably 5,000 to 100,000, in terms of mass average molecular weight. If the mass average
molecular weight is less than 1000, the fluorine-containing block copolymer tends to bleed out
and the waterproof performance is lowered. On the other hand, when the mass average
molecular weight exceeds 100,000, the fluorine-containing block copolymer is not sufficiently
oriented on the surface, and the waterproof performance tends to be lowered.
[0038]
Next, the polymerization solvent and the dilution solvent will be described. The polymerization
solvent and the dilution solvent are not particularly limited as long as they are organic solvents
capable of dissolving or dispersing the fluorine-containing block copolymer. Specifically, acetone,
methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl acetate, butyl acetate, methyl
cellosorb acetate, tetrahydrofuran, dimethylformamide, dimethyl acetamide, toluene, ethyl
benzene, xylene, hexane, heptane, isoparaffin based solvent Made: NAS-3, NAS-4, NAS-5H],
methyl alcohol, ethyl alcohol, propyl alcohol and the like. One or two or more of these organic
solvents can be used. Among these, methyl ethyl ketone, methyl isobutyl ketone, butyl acetate,
toluene, ethyl benzene, xylene, heptane, propyl alcohol and the like can be mentioned as organic
solvents suitable for dissolving or dispersing the fluorine-containing block copolymer.
[0039]
There are various methods as a method of forming a film by diluting the fluorine-containing
block copolymer with the above-mentioned organic solvent and coating or impregnating it on the
surface of the speaker diaphragm. For example, a fluorine-containing block copolymer is made to
adhere to the surface of the speaker diaphragm by a method of spray coating a 1 to 10% by mass
solution of the fluorine-containing block copolymer on the speaker diaphragm, or The speaker
diaphragm can be impregnated with the fluorine-containing block copolymer by immersing the
speaker diaphragm in a 1 to 10% by mass solution of the polymer.
[0040]
The fluorine-containing block copolymer is preferably coated in a small amount of 0.1 to 10% by
mass, and more preferably 1 to 5% by mass, with respect to the speaker diaphragm. If the
11-05-2019
13
amount to be coated is less than 0.1% by mass, it is difficult to obtain waterproofness of the film,
and if it is more than 10% by mass, it is excessive and the sound quality emitted from the speaker
diaphragm is not preferable. In other words, the thickness of the film formed on the surface of
the speaker diaphragm is preferably 0.1 to 100 μm. When the thickness is less than 0.1 μm,
the waterproof performance can not be sufficiently exhibited. When the thickness exceeds 100
μm, the sound quality from the speaker diaphragm tends to be deteriorated.
[0041]
Next, the speaker diaphragm will be described. The speaker diaphragm is composed of a conical
cylindrical (trumpet-shaped) diaphragm main body and a disk-like edge member joined to the
enlarged diameter side edge of the diaphragm main body. The diaphragm main body is formed
into a thin plate by a heat press molding method after making a paper by the paper making
method by adding a dye, a paper strength agent, a sizing agent, a coagulant and the like to the
beaten pulp. The edge member is formed into a thin plate by a foamed polyurethane resin. The
speaker diaphragm is disposed in the speaker, and generates a predetermined sound by vibrating
based on the electric signal. The speaker equipped with the speaker diaphragm may be any of a
car speaker, a loud speaker, a recorder speaker, a radio speaker, and a television speaker.
[0042]
Now, in the case of forming a film on the surface of the speaker diaphragm using the film
forming material of the present embodiment, an organic solvent solution of the fluorinecontaining block copolymer is prepared by the two-step polymerization method described above.
On the other hand, a speaker diaphragm is manufactured using pulp in accordance with a
conventional method of papermaking. Then, the speaker diaphragm is dip-coated in the organic
solvent solution of the fluorine-containing block copolymer, or the organic solvent solution of the
fluorine-containing block copolymer is spray-coated on the surface of the speaker diaphragm.
Thereby, a film of the fluorine-containing block copolymer is formed on the surface of the
speaker diaphragm.
[0043]
The fluorine-containing block copolymer constituting this film is composed of a fluorinecontaining polymer segment formed of a fluorine-containing monomer and a non-fluorinated
11-05-2019
14
polymer segment formed of a fluorine-free monomer. ing. The non-fluorinated polymer segment
exerts an excellent bonding power due to the good affinity to the paper constituting the speaker
diaphragm, while the fluoropolymer segment has a fluoroalkyl group, in particular the CF3 group
at the tip is the surface of the speaker diaphragm They are arranged uniformly and provide a
significant reduction in surface energy to provide waterproofness.
[0044]
Therefore, even if the film of the fluorine-containing block copolymer formed on the surface of
the speaker diaphragm is thin, its function can be sufficiently exhibited over a long period of
time. As a result, the influence exerted on the sound quality and the sound pressure of the sound
emitted from the speaker diaphragm can be suppressed. For example, when the speaker
diaphragm is attached to a speaker mounted on a car door, the speaker diaphragm has good
waterproof performance even if it receives raindrops when the door is opened or closed. The
sound quality from the speaker diaphragm can be maintained without soaking into the speaker
diaphragm.
[0045]
On the other hand, in the case of a random copolymer, since a portion formed of a monomer
containing fluorine and a portion formed of a monomer not containing fluorine exist at random,
they are formed of a monomer containing fluorine The waterproofing performance based on the
part being weakened is weakened by the part formed from the fluorine-free monomer. At the
same time, the adhesion exhibited by the part formed from the fluorine-free monomer is
weakened by the part formed from the fluorine-containing monomer. Therefore, in the case of
the random copolymer, the waterproof performance of the film is low, and the adhesion to the
speaker diaphragm is also low.
[0046]
The effects exerted by the above embodiments will be described below. The film forming material
used for the speaker diaphragm of the embodiment includes a fluorine-containing polymer
segment formed from a fluorine-containing monomer and a non-fluorinated polymer segment
formed from a fluorine-free monomer And a fluorine-containing block copolymer comprising
Therefore, the film on the surface of the speaker diaphragm formed of the film-forming material
11-05-2019
15
can exhibit excellent adhesion to the speaker diaphragm due to the non-fluorinated polymer
segment, and at the same time the fluorine-containing polymer The segment can exhibit superior
waterproof performance. Therefore, such a coating can maintain excellent waterproof
performance over a long period of time. As a result, it is possible to suppress the deterioration of
the sound quality from the speaker diaphragm.
[0047]
When the fluorine-containing polymer segment of the fluorine-containing block copolymer is
formed of only a fluorine-containing monomer, the content of fluorine is high, and the
waterproof performance can be improved. When the fluorine-containing polymer segment is
formed of a mixture of a fluorine-containing monomer and an alkyl (meth) acrylate having 12 to
22 carbon atoms in the alkyl group, the film is dried at normal temperature to obtain a film. Also
in the case, the waterproof performance of the coating can be improved.
[0048]
When the fluorine-containing monomer is the monomer represented by the general formula (A),
the polymerization conversion of the block copolymer can be increased, and the surface of the
speaker diaphragm is coated. The waterproof performance of the coating can be improved.
[0049]
The yield of the fluorine-containing block copolymer can be improved by adopting a two-step
polymerization method in which polymerization is performed using a polymeric peroxide as a
polymerization initiator in the method of producing the fluorine-containing block copolymer. The
fluorine-containing block copolymer can be easily produced.
[0050]
Synthesis Example of Fluorine-Containing Block Copolymer Preparation Example 1 Nitrogen gas
was introduced into a 500 ml four-necked flask equipped with a thermometer, a dropping float, a
nitrogen gas introducing pipe, and a stirring device, and then 60.0 g of methyl ethyl ketone Then,
the temperature was raised to 70.degree.
Thereafter, a mixture of 45.0 g of methyl methacrylate and 6.7 g of a polymeric peroxide (n = 10
11-05-2019
16
in the above general formula (1)) and 50.0 g of methyl ethyl ketone as non-fluorinated
monomers forming non-fluorinated polymer segments for 2 hours It dripped at.
Thereafter, the polymerization reaction was continued at 70 ° C. for 4 hours. Subsequently, 50.0
g of the fluorine-containing monomer represented by the formula (a-2) and 116.7 g of methyl
ethyl ketone were dropped in one hour. Thereafter, a polymerization reaction was carried out at
70 ° C. for 5 hours.
[0051]
The obtained solution was heat-treated at 150 ° C. for 2 hours, and then methyl ethyl ketone
was removed to measure the mass. As a result, 30 mass% of the methyl ethyl ketone solution was
a fluorine-containing block copolymer. It was revealed from pyrolysis gas chromatography
analysis that the obtained fluorine-containing block copolymer was composed of 50% by mass of
the fluorine-containing polymer and 50% by mass of the non-fluorinated polymer.
[0052]
Production Examples 2 to 5 In the synthesis of the fluorine-containing block copolymer in
Production Example 1, the types of monomers formed in the non-fluorinated polymer segment
and the fluorinated polymer segment are changed as shown in Table 1 Were carried out in the
same manner as in Production Example 1 and the results are shown in Table 1.
[0053]
Production Examples 6 to 7 In the synthesis of the fluorine-containing block copolymer in
Production Example 1, the proportions of the fluorine-containing polymer segment and the nonfluorinated polymer segment in the fluorine-containing block copolymer are as shown in Table 1
Thus, the procedure of Production Example 1 was repeated except that the amount of monomer
used was changed, and the results are shown in Table 1.
[0054]
Synthesis Example of Fluorine-Containing Random Copolymer Production Example 8 After
introducing nitrogen gas into the four-necked flask described in Production Example 1, 175 g of
methyl ethyl ketone was added, and the temperature was raised to 60 ° C.
11-05-2019
17
Thereafter, a mixture of 50 g of methyl methacrylate, 50 g of the fluorine-containing monomer
represented by (a-2), 1.0 g of t-butylperoxypivalate and 50 g of toluene was added dropwise over
2 hours.
Thereafter, the polymerization reaction was continued at 60 ° C. for 7 hours.
[0055]
As a result of measurement of heating residue, 30% by mass in the toluene solution is a fluorinecontaining random copolymer, and the obtained fluorine-containing random copolymer is 50%
by mass of a fluorine-containing polymer and a non-fluorinated polymer It became clear from
pyrolysis gas chromatography analysis that it consists of 50% by mass.
[0056]
Production Examples 9 to 12 The synthesis was carried out in the same manner as in Production
Example 8 except that in the synthesis of the fluorine-containing random copolymer in
Production Example 8, the types of monomers were changed as shown in Table 2, the results are
shown in Table 2 shows.
[0057]
Production Examples 13 and 14 The same as Production Example 8, except that the amount of
the monomers used is changed so as to obtain the values shown in Table 2 in the synthesis of the
fluorine-containing random copolymer in Production Example 8 The results are shown in Table
2.
[0058]
The abbreviations in Tables 1 and 2 are shown below.
(a-2): F (CF2) 8 (CH2) 2OCOCH = CH2 (a-6): (CF3) 2CF (CF2) 8 (CH2) 2OCOCH = CH2 (b-2): F
(CF2) 8SO2N (CH3 ) (CH 2) 4 OCOCH = CH 2 SMA: stearyl methacrylate SA: stearyl acrylate
MMA: methyl methacrylate iBMA: i-butyl methacrylate HEMA: 2-hydroxyethyl methacrylate St:
styrene MAA: methacrylic acid (Examples 1 to 7) First, softwood-based unbleached kraft pulp
11-05-2019
18
was beaten to 700 ml of canadian freeness, and a predetermined dye, paper strength agent and
sizing agent were added and stirred.
Next, aluminum sulfate (a sulfuric acid band manufactured by Sumitomo Chemical Co., Ltd.) was
added while stirring until the pH of the bulp solution became 5.0.
The obtained pulp solution was made into a diaphragm on a diaphragm with a diaphragm-shaped
papermaking net, and a diaphragm for a speaker was obtained by heat press molding. And the
diaphragm for speakers is dip-coated on the solution diluted with methyl ethyl ketone so that the
fluorine-containing block copolymer of the said manufacture examples 1-7 becomes 10 mass%
for speakers, and drying for 10 minutes at 80 degreeC is carried out. As a result, the thickness of
the film formed on the surface of the speaker diaphragm was 5 μm. It was 3 mass%, when the
mass increase rate of the obtained diaphragm for speakers was measured. The obtained speaker
diaphragm was used for the following performance test, and the results are shown in Table 3.
[0059]
Comparative Examples 1 to 7 A speaker diaphragm was obtained in the same manner as in
Examples 1 to 7. Then, using the fluorine-containing random copolymers of Production Examples
8 to 14, a solution diluted with methyl ethyl ketone is prepared in the same manner as in
Examples 1 to 7, and the speaker diaphragm is dip coated and dried. The It was 3 mass%, when
the mass increase rate of the obtained diaphragm for speakers was measured. The obtained
speaker diaphragm was used for the following performance test, and the results are shown in
Table 4.
[0060]
Comparative Example 8 The following performance test was conducted using the speaker
diaphragm not coated with the fluorine-containing block copolymer and the fluorine-containing
random copolymer, and the results are shown in Table 4.
[0061]
[Performance Test] (Durable Water Resistance Test) The diaphragm was subjected to showering
at a flow rate of 100 ml / min for 24, 72 and 120 hours, and the water wet state of the speaker
diaphragm surface was evaluated based on the following criteria.
11-05-2019
19
[0062]
○: no wetness observed
Fair: Partial wetting is observed.
X: The whole can be seen wet.
[0063]
(Sound quality test) The speaker diaphragm using the speaker diaphragm after performing the
above-mentioned endurance waterproofness test for 120 hours and the speaker diaphragm
which is not coated with the fluorine-containing block copolymer and the fluorine-containing
random copolymer Made. And with the monitor of 10 people (5 men, 5 women), the sound
quality was confirmed according to the following criteria.
[0064]
○: All monitors can not feel the deterioration of sound quality. Fair: Six to nine monitors can not
feel the deterioration of sound quality. X: Five or more monitors felt a drop in sound quality.
[0065]
[0066]
[0067]
[0068]
11-05-2019
20
As shown in Table 3, in Examples 1 to 7 no watering was observed in the endurance
waterproofing test for 24 hours and 72 hours, and in Examples 1 to 3, 5 and 7, the endurance
waterproofing test for 120 hours I can not see the water at all.
Moreover, in Examples 1-7, there is no fall of sound quality by a sound quality test.
On the other hand, as shown in Table 4, in Comparative Examples 4, 6 and 8, water wetting was
observed in the durability waterproofing test for 24 hours, and in Comparative Examples 3, 5
and 7, water wetting was obtained in the durability waterproofing test for 72 hours. In
Comparative Examples 1 and 2, water wetting was observed in the durability waterproofing test
for 120 hours.
Moreover, in Comparative Examples 1 to 8, deterioration of the sound quality was observed in
the sound quality test.
[0069]
The above embodiment or example can be modified and embodied as follows. -As a material of
the diaphragm for the speaker, in addition to a paper made of pulp, a fiber made of a
thermoplastic resin such as polypropylene, a fiber material obtained by molding a fiber material
such as carbon fiber or aramid fiber with a thermosetting resin It may be made of resin or the
like.
[0070]
As a method of forming a film by applying an organic solvent solution of a fluorine-containing
block copolymer to the surface of the speaker diaphragm, a method of applying an organic
solvent solution of the fluorine-containing block copolymer with a coating roller, brush or the
like It can also be adopted.
[0071]
The film-forming material may also be blended with a monomer having water repellency other
11-05-2019
21
than fluorine, such as a block copolymer formed from a monomer having silicon.
-Containing a fluorine-containing polymer segment formed from a fluorine-containing monomer
and a non-fluorinated polymer segment formed from a fluorine-free monomer as a trunk portion
or a branch portion in the film forming material It is also possible to blend a fluorine graft
copolymer.
[0072]
Furthermore, technical ideas that can be grasped from the above embodiment or examples will
be described below. The film forming material according to any one of claims 1 to 4, wherein the
speaker diaphragm is made of paper. When configured in this manner, good adhesion of the
coating to the speaker diaphragm can be obtained.
[0073]
A diaphragm for a speaker, wherein a film is formed on the surface of the film-forming material
according to any one of claims 1 to 4. When configured in this manner, it is possible to obtain a
speaker diaphragm that is excellent in waterproof performance over a long period of time
because deterioration in sound quality is suppressed.
11-05-2019
22
Документ
Категория
Без категории
Просмотров
0
Размер файла
35 Кб
Теги
jp2005094270
1/--страниц
Пожаловаться на содержимое документа