close

Вход

Забыли?

вход по аккаунту

?

DESCRIPTION JP2015210927

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 JP2015210927
PROBLEM TO BE SOLVED: To provide a conductive film having a soft and smooth surface and
having high adhesion to a partner member. Provided are a conductive tape member and an
electronic component using the conductive film. SOLUTION: A conductive film 10 has an
elastomer and a conductive material, and has an arithmetic average roughness (Ra) less than 0.5
μm or a maximum height roughness (Rz) of 15 μm as an adhesive surface to be bonded to a
mating member. Having less than 100 smooth surfaces 101, 102. The conductive tape member 1
includes a conductive film 10 and release sheets 11 and 12 disposed on at least one surface in
the thickness direction of the conductive film 10. The electronic component includes the
conductive film 10 as at least one of an electrode, a wiring, and a connection member electrically
connecting the members. [Selected figure] Figure 1
Conductive film, conductive tape member and electronic component using the same
[0001]
The present invention relates to a conductive film used for electronic components such as a
transducer and a flexible wiring board, and a conductive tape member using the same.
[0002]
As the transducer, an actuator for converting mechanical energy and electrical energy, a sensor, a
power generation element, an element for haptics or the like, or a speaker for converting acoustic
energy to electrical energy, a microphone and the like are known.
14-04-2019
1
For example, a flexible transducer can be configured by arranging a pair of electrodes on both
sides in the thickness direction of an elastomeric dielectric film. In this type of transducer,
flexibility is also required for electrodes and wiring so as to be able to follow deformation of the
dielectric film. For this reason, a flexible conductive material in which a conductive material such
as carbon black is blended into an elastomer has been developed (see, for example, Patent
Document 1). When the electrode is formed of a flexible conductive material, the method of
connecting the electrode and the wiring of the circuit board becomes an issue.
[0003]
For example, in a piezoelectric element using a piezoelectric body, the electrode and the wiring of
the circuit board are connected by solder, silver paste or the like. Further, Patent Document 2
describes that a flexible sheet is interposed between an electrode of a piezoelectric element and a
lead wire. Patent Document 3 describes that an electrode of a piezoelectric element and a wiring
of a flexible substrate are connected using an anisotropic conductive adhesive.
[0004]
JP, 2009-227985, A JP, 2002-16300, A JP, 2014-026449, A
[0005]
The flexible conductive material is obtained by dispersing a conductive material in an elastomer.
For this reason, when the dispersed state of the conductive material is not good, when the
conductive material is formed into a thin film, the surface roughness of the film becomes large.
When a conductive film having a large surface roughness is used for the electrode, the contact
area of the electrode with a mating member such as a dielectric film is small, and the adhesion is
reduced. For this reason, when the dielectric film is repeatedly deformed, the electrode may be
peeled off. In addition, when the dielectric film is repeatedly deformed, stress may be
concentrated on the bonded portion and the electrode may be broken. In addition, since the
electrodes are not in uniform contact with the dielectric film, the electrical characteristics and the
reliability may vary.
14-04-2019
2
[0006]
On the other hand, when joining an electrode and the wiring of a circuit board with solder, the
influence on the member by being exposed to high temperature at the time of soldering may be
concerned. Also, solder is a hard metal. For this reason, when the members to be joined expand,
contract or vibrate, stress may concentrate on the interface with the members and break.
Moreover, when the members to be joined include an elastomer, joining by solder is difficult.
[0007]
Also when joining an electrode and wiring of a circuit board with silver paste, since it is
necessary to harden silver paste at high temperature, there is a concern about the influence on a
member. In addition, since the elastic modulus after curing of the silver paste is large, when the
members to be joined expand and contract and vibrate, stress may concentrate on the interface
with the members and break. In addition, when the silver paste and the counterpart member are
not in uniform contact with each other, the electrical characteristics and the reliability may be
varied.
[0008]
The present invention has been made in view of such circumstances, and it is an object of the
present invention to provide a conductive film having a soft and smooth surface and having high
adhesion to a mating member. Another object of the present invention is to provide a conductive
tape member and an electronic component using the conductive film.
[0009]
(1) The conductive film of the present invention has an elastomer and a conductive material, and
has an arithmetic average roughness (Ra) of less than 0.5 μm or a maximum height roughness
(Rz) as an adhesive surface to be bonded to a mating member. It is characterized by having a
smooth surface of less than 15 μm.
[0010]
14-04-2019
3
The conductive film of the present invention uses an elastomer as a base material.
Elastomers include rubber and thermoplastic elastomers. Therefore, the conductive film of the
present invention is flexible, and can be deformed following the movement of the counterpart
member even if the counterpart member to which the conductive film is bonded is expanded and
contracted. Therefore, stress is less likely to be concentrated at the interface with the mating
member, and breakage of the conductive film is suppressed. In addition, according to the
conductive film of the present invention, thin film formation is easy and arrangement over a wide
range is easy.
[0011]
According to the conductive film of the present invention, adhesion to the counterpart member is
easy due to the adhesiveness of the elastomer. The conductive film of the present invention has a
smooth surface as a bonding surface to be bonded to the other member. For example, when both
surfaces in the thickness direction of the conductive film are adhesive surfaces, the smooth
surface may be only one of the surfaces or both surfaces. By smoothing the bonding surface to
the mating member, the contact area with the mating member is increased, and the adhesion is
improved. For this reason, the conductive film of the present invention is not easily peeled off
even if the counterpart member moves due to expansion, contraction, vibration or the like. For
example, if the contact area with the other member is small, stress concentration is likely to
occur at the contact portion. In this respect, according to the conductive film of the present
invention, since the contact area is large, partial stress concentration hardly occurs. Therefore,
the conductive film of the present invention is unlikely to be broken and is excellent in reliability.
In addition, even if the deformation is repeated following the mating member, the electrical
resistance is unlikely to increase.
[0012]
The conductive film of the present invention is suitable for electrodes, wires, and connection
members for electrically connecting members in electronic parts such as transducers and flexible
wiring boards. For example, when the conductive film of the present invention is used as an
electrode of an actuator which is one of flexible transducers, the generation force can be
increased. In addition, when the conductive film of the present invention is used as an electrode
of a speaker, a large sound pressure can be obtained.
14-04-2019
4
[0013]
The arithmetic mean roughness (Ra) and the maximum height roughness (Rz) in the conductive
film of the present invention conform to JIS B0601: 2001. In the present specification, as Ra and
Rz, values measured by a shape measuring laser microscope (laser microscope) “VK-X100”
manufactured by Keyence Corporation are adopted.
[0014]
(2) The conductive tape member of the present invention is characterized by comprising the
conductive film of the configuration of the above (1) and a release sheet disposed on at least one
surface in the thickness direction of the conductive film.
[0015]
The conductive tape member of the present invention can be easily transported and has excellent
workability.
The release sheet may be disposed only on one side in the thickness direction of the conductive
film, or may be disposed on both sides. For example, when the release sheet is disposed only on
one surface of the conductive film, first, the other surface of the conductive film is pressurebonded to the opposite member, and then the release sheet is peeled off. It should be crimped to
When release sheets are disposed on both sides of the conductive film, first, one release sheet is
peeled off, one surface exposed is pressure-bonded to the other member, and then the other
release sheet is peeled off. The other surface may be crimped to another mating member. As
described above, according to the conductive tape member of the present invention, the
conductive film can be easily bonded to the mating member without heating. Further, the
conductive tape member of the present invention can be obtained by disposing release sheets on
both sides in the thickness direction of the conductive film, or by placing the release sheets on
the entire surface in the thickness direction and winding the conductive film inside. It becomes
easier to carry.
[0016]
(3) The electronic component of the present invention is characterized by including the
conductive film of the above configuration (1) as at least one of an electrode, a wiring, and a
14-04-2019
5
connecting member for electrically connecting the members.
[0017]
In the electronic component of the present invention, the conductive film is flexible because it
uses an elastomer as a base material.
For this reason, even if the counterpart member to which the conductive film is bonded expands,
contracts, or vibrates, the conductive film deforms following the movement of the counterpart
member. Therefore, stress is less likely to be concentrated at the interface with the mating
member, and breakage of the conductive film is suppressed. Further, in the state where the
smooth surface of the conductive film and the mating member are bonded, the contact area
between the conductive film and the mating member is large, and the adhesion is high. In this
case, even if the counterpart member moves due to expansion and contraction, vibration or the
like, the conductive film is not easily peeled off. In addition, since the contact area is large, partial
stress concentration is unlikely to occur in the conductive film. Therefore, the conductive film is
less likely to be broken and the reliability is excellent. In addition, even if the deformation is
repeated following the mating member, the electrical resistance of the conductive film is difficult
to increase. The electronic component of the present invention can be embodied as a transducer,
a flexible wiring board or the like provided with a member that expands and contracts, bends or
vibrates.
[0018]
It is sectional drawing of 1st embodiment of the electroconductive tape member of this invention.
It is a top view of the speaker which is a first embodiment of the electronic component of the
present invention. It is the III-III sectional view of FIG. It is IV-IV sectional drawing of FIG. It is a
SEM photograph of the lamination direction section in the layered product (example 5) of electric
conduction film B and dielectric film. It is a SEM photograph of the lamination direction section
in the layered product (comparative example 1) of conductive film A and dielectric film which
have not performed smoothing processing. It is a fragmentary sectional view of the piezoelectric
actuator manufactured in order to measure electrical resistance.
[0019]
14-04-2019
6
Hereinafter, embodiments of the conductive film, the conductive tape member, and the electronic
component of the present invention will be described. The conductive film, the conductive tape
member, and the electronic component of the present invention are not limited to the following
embodiments, and modifications, improvements, etc. which can be made by those skilled in the
art are made without departing from the scope of the present invention. It can be implemented in
various forms.
[0020]
<Conductive Film> The conductive film of the present invention comprises an elastomer and a
conductive material. The conductive film may contain, in addition to the elastomer and the
conductive material, if necessary, additives such as a dispersant, a reinforcing agent, a plasticizer,
an antiaging agent, and a colorant.
[0021]
The type of elastomer is not particularly limited. Silicone rubber, nitrile rubber (NBR),
hydrogenated nitrile rubber (H-NBR), ethylene-propylene-diene rubber (EPDM), as a suitable
elastomer from the viewpoint of being flexible and easily deformed following the movement of a
mating member Natural rubber, styrene-butadiene rubber (SBR), acrylic rubber, urethane rubber,
epichlorohydrin rubber, crosslinked rubber such as chlorosulfonated polyethylene, chlorinated
polyethylene, and styrene type, olefin type, polyvinyl chloride type, polyester type, polyurethane
type And thermoplastic elastomers such as polyamides. Alternatively, an elastomer modified by
introducing a functional group may be used, such as an epoxy group-containing acrylic rubber or
a carboxyl group-containing hydrogenated nitrile rubber.
[0022]
The type of conductive material is not particularly limited. It may be appropriately selected from
carbon black, carbon nanotubes, carbon materials such as graphite, and metal powders such as
silver, gold, copper, nickel, rhodium, palladium, chromium, titanium, platinum, iron, and alloys
thereof. Also, coated particles in which the surface of particles other than metal is coated with
metal may be used. In this case, the specific gravity of the conductive material can be reduced as
compared to the case of using only metal. Therefore, when it is made a paint, the sedimentation
14-04-2019
7
of the conductive material is suppressed, and the dispersibility is improved. Further, by
processing the particles, conductive materials of various shapes can be easily manufactured. In
addition, the cost of the conductive material can be reduced. As the metal to be coated, metal
materials such as silver listed above may be used. As particles other than metal, carbon materials
such as carbon black, metal oxides such as calcium carbonate, titanium dioxide, aluminum oxide
and barium titanate, inorganic substances such as silica, resins such as acrylic and urethane, etc.
may be used. A conductive material may be used individually by 1 type, and may mix and use 2
or more types.
[0023]
From the viewpoint of securing flexibility, the elastic modulus of the conductive film is desirably
less than 50 MPa. It is more preferable that the pressure be less than 20 MPa. From the
viewpoint of achieving desired conductivity even when stretched, the volume resistivity in the
case where the conductive film is stretched by 30% in the uniaxial direction is desirably less than
10 Ω · cm. It is more preferable to set it to less than 5 Ω · cm. The type, particle diameter, shape,
compounding amount, and the like of the conductive material may be determined so that the
flexibility and conductivity of the conductive film can be compatible.
[0024]
The conductive film of the present invention has a smooth surface having an arithmetic average
roughness (Ra) of less than 0.5 μm or a maximum height roughness (Rz) of less than 15 μm as
an adhesive surface to be bonded to the other member. When Ra is 0.5 μm or more or Rz is 15
μm or more, the smoothness is reduced and the contact area with the other member is reduced.
As a result, the adhesion is lowered and it becomes easy to peel off from the mating member. In
addition, with the expansion and contraction, vibration and the like of the mating member, stress
concentrates on the contact portion and it is easily broken. The surface roughness of the smooth
surface may satisfy either Ra <0.5 μm or Rz <15 μm. It is more preferable to satisfy both.
[0025]
In order to realize a smooth surface, the dispersibility of the conductive material may be
improved, or the surface of the conductive film may be smoothed. In order to improve the
dispersibility of the conductive material, methods such as adjusting the particle diameter, shape
14-04-2019
8
and the like according to the type of the conductive material, blending a dispersing agent, and
using a dispersing machine such as an ultrasonic homogenizer may be used. . As a smoothing
process, a rolling process, a thermocompression-bonding process, a vacuum pressure-bonding
process etc. are mentioned.
[0026]
The rolling process may be performed as follows. First, a conductive material and, if necessary,
additives are dispersed in a polymer solution in which a polymer of an elastomer component is
dissolved in a solvent to prepare a conductive paint. Next, the prepared conductive paint is
applied to the surface of the first member and dried to form a coating. Subsequently, the second
member is disposed on the surface of the coating film, and a laminate of the first member /
coating film / second member is produced. Then, the produced laminate is rolled between two
rollers and rolled. In this case, the first member and the second member may be either a base
having releasability or a counterpart to which the conductive film is bonded. Further, the first
member and the second member may be members made of one layer or members made of plural
layers.
[0027]
The thermocompression bonding may be performed as follows. First, in the same manner as in
the rolling process, a laminate of the first member / coating film / second member is produced.
Next, the produced laminated body is pressed under heating.
[0028]
The vacuum pressure bonding process may be performed as follows. First, in the same manner as
in the rolling process, a laminate of the first member / coating film / second member is
produced. Next, the produced laminated body is pressed using a vacuum press.
[0029]
According to the conductive film of the present invention having such a smooth surface, when
14-04-2019
9
the cross section in the lamination direction of the conductive film and the counterpart member
is observed in a state where the smooth surface is adhered to the counterpart member, the
conductive film and the counterpart member at the interface The non-contact rate with can be
made 10% or less. When the non-contact rate is 10% or less, the contact area between the
conductive film and the opposite member becomes large, and the adhesion becomes high.
[0030]
The observation of the cross section in the stacking direction of the conductive film and the
opposite member may be performed using a scanning electron microscope (SEM). Then, in the
obtained SEM photograph, the length of the interface between the conductive film and the
mating member and the length of the non-contact portion where the conductive film and the
mating member are not in contact at the interface are measured. Calculate the non-contact rate
by). Non-contact rate (%) = (total length of non-contact portion / length of interface) × 100 (1)
<Conductive tape member> The conductive tape member of the present invention is the
conductive material of the present invention described above And a release sheet disposed on at
least one surface in the thickness direction of the conductive film. The configuration and
manufacturing method of the conductive film of the present invention are as described above.
Therefore, the description is omitted here. Also in the conductive tape member of the present
invention, it is desirable to adopt a preferred embodiment of the conductive film of the present
invention.
[0031]
FIG. 1 shows a cross-sectional view of a first embodiment of the conductive tape member of the
present invention. As shown in FIG. 1, the conductive tape member 1 includes a conductive film
10, a first release sheet 11, and a second release sheet 12.
[0032]
The conductive film 10 has a rectangular thin film shape, and contains acrylic rubber and carbon
black. The first release sheet 11 is disposed on the lower surface 101 of the conductive film 10.
The first release sheet 11 is made of polyethylene terephthalate (PET), and has the same
rectangular thin film shape as the conductive film 10. The second release sheet 12 is disposed on
the upper surface 102 of the conductive film 10. The second release sheet 12 is also made of
14-04-2019
10
PET and has the same rectangular thin film shape as the conductive film 10. In both the lower
surface 101 and the upper surface 102 of the conductive film 10, Ra is 0.25 μm and Rz is 3.6
μm. The lower surface 101 and the upper surface 102 are included in the concept of a smooth
surface in the conductive film of the present invention.
[0033]
In order to bond the conductive tape member 1 to a mating member (not shown), the second
release sheet 12 is first peeled off, and the exposed upper surface 102 is crimped to the mating
member. Next, the first release sheet 11 is peeled off, and the exposed lower surface 101 is
crimped to another mating member. As described above, according to the conductive tape
member 1, the conductive film 10 can be easily bonded to the other member.
[0034]
In the present embodiment, a PET sheet is used as the release sheet, but the material of the
release sheet is not particularly limited. For example, polyethylene, polytetrafluoroethylene
(PTFE) and the like can be mentioned. In the present embodiment, the release sheet is disposed
on both sides in the thickness direction of the conductive film (the lower surface 101 and the
upper surface 102 in FIG. 1), but the release sheet is disposed only on one surface in the
thickness direction of the conductive film It is also good. In the present embodiment, both
surfaces in the thickness direction of the conductive film are smooth surfaces, but only one
surface in the thickness direction of the conductive film may be a smooth surface. For example,
the adhesive surface of the conductive film bonded to the stationary member does not have to be
a smooth surface.
[0035]
<Electronic Component> The electronic component of the present invention comprises the
conductive film of the present invention as at least one of an electrode, a wiring, and a
connecting member electrically connecting the members. The configuration and manufacturing
method of the conductive film of the present invention are as described above. Therefore, the
description is omitted here. Also in the electronic component of the present invention, it is
desirable to adopt a preferred embodiment of the conductive film of the present invention. For
example, in a state where the conductive film and the counterpart member to which the smooth
14-04-2019
11
surface of the conductive film is adhered are stacked, the cross section in the lamination
direction of the conductive film and the counterpart member is observed, and the length of the
interface and the interface The non-contact ratio is 10% or less when the non-contact ratio is
calculated by the above equation (1) based on the length of the non-contact portion where the
conductive film and the counterpart member are not in contact with each other. desirable.
[0036]
In the electronic component of the present invention, the counterpart member to be bonded to
the conductive film is not particularly limited, but in the case of a member which is stretched,
bent or vibrated, the effect of the present invention is more exhibited. That is, since the adhesion
between the conductive film and the mating member is high, the conductive film is not easily
peeled off even if the mating member moves due to expansion, contraction, vibration or the like.
In addition, since a partial stress concentration does not easily occur in the conductive film, the
conductive film is less likely to be broken and the reliability is excellent. Examples of the member
that expands and contracts, bends or vibrates include a dielectric film that is a component of a
transducer, a piezoelectric body, a wiring board, and a substrate of a flexible wiring board.
[0037]
Hereinafter, an embodiment in which the electronic component of the present invention is
embodied in a speaker which is one of the transducers will be described.
[0038]
[Configuration] First, the configuration of the speaker of this embodiment will be described.
The top view of the speaker of this embodiment is shown in FIG. In FIG. 3, III-III sectional
drawing of FIG. 2 is shown. In FIG. 4, IV-IV sectional drawing of FIG. 2 is shown. As shown in
FIGS. 2 to 4, the speaker 2 includes an electrostrictive element 20, an upper frame 21a, and a
lower frame 21b. The speaker 2 is disposed on the upper surface of the substrate 3 made of
silicone rubber.
[0039]
14-04-2019
12
The upper frame 21a and the lower frame 21b are each made of resin and have a ring shape. The
upper frame 21 a and the lower frame 21 b are disposed to face each other with the peripheral
portion of the electrostrictive element 20 interposed therebetween. The upper frame 21a and the
lower frame 21b are fixed by four bolts 210 and four nuts (not shown). The set of “bolt 210nut” is arranged at predetermined intervals in the circumferential direction of the speaker 2.
The bolt 210 penetrates from the upper surface of the upper frame 21a to the lower surface of
the lower frame 21b. The nut is screwed to the through end of the bolt 210.
[0040]
The electrostrictive element 20 is interposed between the upper frame 21a and the lower frame
21b. The electrostrictive element 20 includes a dielectric film 22 and a pair of electrodes 23a
and 23b. The dielectric film 22 is made of hydrogenated nitrile rubber (H-NBR), and has a
circular thin film shape.
[0041]
Each of the electrodes 23a and 23b contains acrylic rubber and carbon black. The elastic
modulus of the electrodes 23a and 23b is 2.4 MPa. The volume resistivity in the natural state of
the electrodes 23a and 23b is 2.5 Ω · cm, and the volume resistivity in the case of 30%
elongation in the uniaxial direction is 3.1 Ω · cm. Each of the electrodes 23 a and 23 b has a
circular thin film shape smaller in diameter than the dielectric film 22. The electrodes 23a and
23b are arranged substantially concentrically with the dielectric film 22, respectively.
[0042]
The electrode 23a has a lower surface 230a having an Ra of 0.25 μm and an Rz of 3.6 μm. The
lower surface 230 a is bonded to the upper surface of the dielectric film 22. The lower surface
230a is included in the concept of a smooth surface in the present invention. The noncontact
ratio between the lower surface 230a and the upper surface of the dielectric film 22 is 0%. The
electrode 23a is included in the concept of the conductive film in the present invention. The
electrode 23 b has an upper surface 230 b with an Ra of 0.25 μm and an Rz of 3.6 μm. The
upper surface 230 b is bonded to the lower surface of the dielectric film 22. The upper surface
230b is included in the concept of a smooth surface in the present invention. The non-contact
14-04-2019
13
ratio between the upper surface 230 b and the lower surface of the dielectric film 22 is 0%. The
electrode 23 b is included in the concept of the conductive film in the present invention.
[0043]
The electrode 23a has a terminal portion 231a. The terminal portion 231a has a strip shape. The
terminal portion 231a protrudes in the radial direction from the outer peripheral edge on the
right side of the electrode 23a, and is disposed on the upper surface of the upper frame 21a. The
electrode 23 b has a terminal portion 231 b. The terminal portion 231 b has a strip shape. The
terminal portion 231b protrudes from the outer peripheral edge slightly forward of the right of
the electrode 23b in the radial direction, and is disposed on the upper surface of the upper frame
21a so as to go around the outer peripheral side of the dielectric film 22 and the upper frame
21a.
[0044]
Two wires 30 a and 30 b are disposed on the upper surface of the substrate 3. The
interconnections 30a, 30b each contain acrylic rubber and silver powder. The elastic modulus of
the wires 30a and 30b is 10.6 MPa. The volume resistivity of the wires 30a and 30b in the
natural state is 1 × 10 <-4> Ω · cm, and the volume resistivity in the case of 30% elongation in
one axial direction is 4.3 × 10 4 <-4> Ω · It is cm. The wires 30a and 30b each have a band
shape. A DC bias power supply and an AC power supply are connected to the not-shown end
portions of the wires 30a and 30b.
[0045]
The terminal portion 231a of the electrode 23a and the wiring 30a are electrically connected by
the connection member 31a. The connection member 31a has a long strip shape. The material of
the connection member 31a is the same as the material of the electrode 23a. The connecting
member 31 a has a lower surface 310 a with an Ra of 0.25 μm and an Rz of 3.6 μm. The lower
surface 310a is bonded to the upper surface of the electrode 23a, the side surface of the speaker
2, the upper surface of the substrate 3, and the upper surface of the wiring 30a. The lower
surface 310a is included in the concept of a smooth surface in the present invention. The
noncontact ratio between the lower surface 310a and the upper surface of the electrode 23a is
7%, and the noncontact ratio between the lower surface 310a and the upper surface of the wiring
14-04-2019
14
30a is 7%. The connection member 31a is included in the concept of the conductive film in the
present invention.
[0046]
The terminal portion 231b of the electrode 23b and the wiring 30b are electrically connected by
the connection member 31b. The connection member 31 b has a long strip shape. The material
of the connection member 31 b is the same as the material of the electrode 23 b. The connecting
member 31 b has a lower surface 310 b with an Ra of 0.25 μm and an Rz of 3.6 μm. The lower
surface 310 b is bonded to the upper surface of the electrode 23 b, the side surface of the
speaker 2, the upper surface of the substrate 3, and the upper surface of the wiring 30 b. The
lower surface 310b is included in the concept of a smooth surface in the present invention. The
non-contact rate between the lower surface 310b and each member is the same as that in the
connection member 31a. The connection member 31 b is included in the concept of the
conductive film in the present invention.
[0047]
[Manufacturing Method] Next, a method of manufacturing the speaker of this embodiment will
be described. First, two release sheets are prepared, and the conductive paint is printed on the
surface of one sheet to form the electrodes 23a. Similarly, the electrode 23b is formed on the
surface of the other sheet. Next, one sheet is attached to the upper surface of the dielectric film
22, the other sheet is attached to the lower surface, and the other sheet is crimped, thereby
transferring the electrode 23a to the upper surface of the dielectric film 22 and transferring the
electrode 23b to the lower surface. Then, the two release sheets are peeled off from the dielectric
film 22. Thus, the electrodes 23a and 23b are formed on the upper and lower surfaces of the
dielectric film 22, and the electrostrictive element 20 is manufactured. Next, the peripheral
portion of the electrostrictive element 20 is sandwiched by the upper frame 21a and the lower
frame 21b. In this state, the upper frame 21a and the lower frame 21b are fixed by four bolts
210 and four nuts. Thus, the speaker 2 is manufactured.
[0048]
Then, the terminal portion 231a of the electrode 23a and the wiring 30a are connected by the
connecting member 31a as follows. First, a conductive paint is printed on the surface of the
14-04-2019
15
release sheet to form the connection member 31a. Next, a release sheet is attached to a
predetermined position from the terminal portion 231a to the wiring 30a, and the connection
member 31a is transferred by pressure bonding. Finally, the release sheet is peeled off. Similarly,
the terminal portion 231b of the electrode 23b and the wiring 30b are connected by the
connection member 31b.
[0049]
[Movement] Next, the movement of the speaker of this embodiment will be described. In the
initial state, a predetermined bias voltage is applied to the electrodes 23a and 23b from a DC bias
power supply. In this state, an AC voltage based on the sound to be reproduced is applied to the
electrodes 23a and 23b from an AC power supply. Then, the electrostrictive element 20 vibrates
in the vertical direction due to the change in the film thickness of the dielectric film 22. As a
result, the air vibrates and a sound is generated.
[0050]
[Operation and Effect] Next, the operation and effect of the speaker of this embodiment will be
described. In the speaker 2 of the present embodiment, the electrodes 23a and 23b are flexible
because they use an elastomer as a base material. Further, the wirings 30a and 30b on the
substrate 3 and the connecting members 31a and 31b connecting the electrodes 23a and 23b to
the wirings 30a and 30b are also flexible because they are made of an elastomer as a base
material. For this reason, these members can be deformed following the movement of the mating
member even if the bonded counterpart member expands, contracts, or vibrates. Therefore,
stress is less likely to be concentrated at the interface with the mating member, and the
electrodes 23a, 23b, etc. are less likely to break.
[0051]
In the speaker 2 of the present embodiment, the adhesion between the electrodes 23 a and 23 b
and the dielectric film 22 is high. Therefore, the electrodes 23a and 23b are less likely to peel off
the dielectric film 22. In addition, since the contact area is large, partial stress concentration on
the electrodes 23a and 23b is unlikely to occur. Therefore, the electrodes 23a and 23b are less
likely to be broken and have excellent reliability. In addition, when the contact area is large, a
large amount of charges can be stored in the dielectric film 22, so that even if the applied voltage
14-04-2019
16
is the same, a larger sound pressure can be obtained.
[0052]
Similarly, the adhesion between the connection members 31a and 31b and the electrodes 23a
and 23b, the substrate 3, and the wirings 30a and 30b is also high. Therefore, the connection
members 31a and 31b are difficult to be peeled off, are not easily broken, and are excellent in
reliability. The connecting members 31a and 31b are bonded without heating. For this reason,
there is no possibility that the members will be deteriorated due to heat.
[0053]
Heretofore, an embodiment of the electronic component of the present invention has been
described. However, the embodiment of the electronic component of the present invention is not
limited to the above embodiment. For example, it may be embodied in other transducers such as
an actuator, a sensor, an element for haptics, a flexible wiring board, and the like. In addition, the
other member to which the conductive film is bonded may be a piezoelectric body, a metal
electrode, a wiring, or the like. For example, the conductive film of the present invention may be
applied to the wiring on the substrate in the above embodiment.
[0054]
In the transducer provided with the electrostrictive element, as a suitable elastomer for the
dielectric film, NBR, EPDM, acrylic rubber, urethane rubber, epichlorohydrin rubber,
chlorosulfonated polyethylene, chlorinated polyethylene, etc. can be mentioned besides H-NBR. .
Alternatively, an elastomer modified by introducing a functional group may be used, such as an
epoxidized natural rubber, a carboxyl group-containing hydrogenated nitrile rubber, and the like.
Resins suitable for the dielectric film include polyethylene, polypropylene, polyurethane,
polystyrene (including cross-linked expanded polystyrene), polyvinyl chloride, vinylidene
chloride copolymer, ethylene-vinyl acetate copolymer, and the like.
[0055]
14-04-2019
17
The dielectric film may contain other components such as additives in addition to the elastomer
or resin component. For example, from the viewpoint of increasing the dielectric breakdown
resistance of the dielectric film, an insulating inorganic filler can be blended. Examples of the
inorganic filler include silica, titanium oxide, barium titanate, calcium carbonate, clay, calcined
clay, and talc.
[0056]
The number of dielectric films and electrodes constituting the electrostrictive element is not
particularly limited. For example, as in the above embodiment, one electrode can be disposed on
each of the upper and lower surfaces of one dielectric film. Alternatively, a plurality of dielectric
films may be stacked via electrodes. In this case, the amount of deformation of the
electrostrictive element with respect to the applied voltage can be increased. In addition, the
electrostrictive element may be fixed to a support member such as a frame in a state in which the
dielectric film is extended in the surface direction.
[0057]
Next, the present invention will be more specifically described by way of examples.
[0058]
<Production of Conductive Film> [Conductive Film A] First, 100 parts by mass of epoxy groupcontaining acrylic rubber ("Nipol (registered trademark) AR42W" manufactured by Nippon Zeon
Co., Ltd.) to 1000 parts by mass of butyl cellosolve acetate (BCA) as a solvent It was dissolved to
prepare a polymer solution.
Next, 10 parts by mass of high conductivity carbon black ketjen black was added to the prepared
polymer solution and dispersed by a bead mill to prepare a conductive paint. The prepared
conductive paint was applied to the surface of a release-treated PET film (base material), dried,
and heated at 150 ° C. for 1 hour to produce a conductive film with a thickness of 5 μm.
[0059]
[Conductive Film B] In the production of the conductive film A, a conductive film was produced in
the same manner as the conductive film A except that dispersion with an ultrasonic homogenizer
14-04-2019
18
was further added after dispersion with a bead mill to prepare a conductive paint.
[0060]
[Conductive Film C] In the production of the conductive film A, the conductive paint is prepared
except that in addition to ketjen black, 16 parts by mass of carbon nanotubes and 12 parts by
mass of polyester acid amide amine salt of dispersant are added. A conductive film was
manufactured in the same manner as the film A.
[0061]
[Conductive Film D] In the production of the conductive film A, the process is the same as the
conductive film A, except that 300 parts by mass of silver powder is added instead of ketjen
black and dispersed by three rolls to prepare a conductive paint. The conductive film was
manufactured.
[0062]
<Measurement of surface roughness of conductive film> [Conductive films A to D bonded to a
dielectric film at room temperature (examples 5 and 8 and comparative examples 1 and 2 in
Table 1 below)] First, thickness direction of dielectric film A conductive film formed on a PET film
(substrate) is laminated on both sides, and pressed between two rubber rollers at 25 ° C. to
bond the substrate / conductive film / dielectric film / conductive film / substrate The laminated
body which consists of materials was produced.
The roller linear pressure was 0.67 kg / cm.
Next, the surface roughness of the bonding surface of one of the conductive films with the
dielectric film was measured with a shape measurement laser microscope (laser microscope)
“VK-X100” manufactured by KEYENCE CORPORATION.
[0063]
The manufacturing method of the used dielectric film is as follows.
14-04-2019
19
The thickness of the dielectric film is 18 μm, and the Ra of the bonding surface to the
conductive film is 0.11 μm. First, roll-kneading a carboxyl group-containing hydrogenated nitrile
rubber polymer ("Terban (registered trademark) XT 8889" manufactured by LANXCESS Inc.) and
silica (wet silica "Nipsil (registered trademark) VN 3" manufactured by Tosoh Silica Corporation)
The mixture was kneaded with a machine to prepare a rubber composition. Next, the prepared
rubber composition was dissolved in acetylacetone. Subsequently, the organic metal compound
tetrakis (2-ethylhexyloxy) titanium was added to and mixed with the obtained polymer solution.
Then, the mixed solution was screen-printed on the surface of an acrylic resin substrate, and
heated at 150 ° C. for 1 hour to produce a dielectric film.
[0064]
[Conductive film D bonded at room temperature to a piezoelectric element (Example 7 in Table 1
described later, Example 7)] Piezoelectric element in which a metal deposition layer is disposed
on one surface in the thickness direction of the piezoelectric body and a metal plate is disposed
on the other surface (Ariose Electronics Co , Ltd. "D35E29B") was used. The thickness of the
piezoelectric body is 300 μm, and Ra of the surface of the metal deposition layer (adhesion
surface to the conductive film) is 0.20 μm. First, a conductive film formed on a PET film (base
material) is laminated on both sides in the thickness direction of the piezoelectric element, and
pressure bonding is performed between two rubber rollers at 25 ° C. to obtain a base material /
conductive film A laminated body composed of: piezoelectric element / conductive film /
substrate was produced. The roller linear pressure was 0.67 kg / cm. Next, the surface roughness
of the bonding surface of the one conductive film and the metal deposition layer of the
piezoelectric element was measured by the same laser microscope.
[0065]
[Conductive Films A and C After Smoothing Treatment (Examples 1 to 4 and 6 in Table 1
Described Below, Examples 1 to 4 and 6)] Furthermore, the conductive films A and C are
subjected to a smoothing treatment to prepare a laminate, The surface roughness of the adhesive
surface after treatment was also measured. The measurement results of surface roughness are
summarized in Table 1 below. Hereinafter, the method of the smoothing process will be
described.
[0066]
14-04-2019
20
(1) Rolling treatment First, the same PET film was laminated on the surface of a conductive film
formed on a PET film (base material) to prepare a laminate of base material / conductive film /
base material. Next, the produced laminated body was rolled through between two metal rollers.
The roller linear pressure was 200 kg / cm. The above is the rolling process. Two laminates thus
rolled were produced. Subsequently, in each of the two laminates, one of the PET films was
peeled off, and a conductive film was laminated on both sides in the thickness direction of the
dielectric film. That is, the substrate was in the state of base / conductive film / dielectric film /
conductive film / base. By pressing this through two rubber rollers at 25 ° C., a laminate of a
substrate / conductive film / dielectric film / conductive film / substrate was produced. The roller
linear pressure was 0.67 kg / cm.
[0067]
(2) Thermocompression bonding treatment A conductive film formed on a PET film (base
material) is laminated on both sides in the thickness direction of the dielectric film, and the
substrate is obtained by pressure bonding through two rubber rollers under heating. A laminate
of / conductive film / dielectric film / conductive film / substrate was produced. The heating
temperature was two kinds of 60 ° C. and 100 ° C. In the case of 60 ° C., the roller linear
pressure was 2.0 kg / cm, and in the case of 100 ° C., the roller linear pressure was 1.3 kg / cm.
[0068]
(3) Vacuum pressure bonding treatment A conductive film formed on a PET film (base material)
is laminated on both sides in the thickness direction of the dielectric film, and pressing is
performed using a vacuum press machine. Base material / conductive film / dielectric film A
laminated body composed of: conductive film / substrate was produced. The contact pressure at
the time of pressing was 0.048 MPa.
[0069]
<Measurement of Non-Contact Rate of Conductive Film and Counterpart Member> In the
manufactured laminate, the noncontact rate of the interface between the conductive film and the
14-04-2019
21
dielectric film or the piezoelectric element (counter member) was measured. For the conductive
films A and C, the noncontact ratio was measured in two types of laminates different in the
presence or absence of the smoothing treatment. First, the laminate was embedded in an epoxy
resin, and a cross section in the stacking direction was cut out by a microtome. Next, a field
emission scanning electron microscope (FE-SEM) was used to take a SEM photograph of the cross
section in the stacking direction. In the obtained SEM photograph, the length of the noncontact
portion at 100 μm of the interface between one of the conductive film and the opposite member
was measured, and the noncontact ratio was calculated by the following equation (1). The
measurement results of the non-contact rate are summarized in Table 1 below. Non-contact ratio
(%) = (total length of non-contact portion / length of interface) × 100 (1) A laminated body of a
conductive film B and a dielectric film as shown in FIG. The SEM photograph of the cross section
of the lamination direction (film thickness direction) in Example 5 in is shown. The SEM
photograph of the lamination direction (film thickness direction) cross section in the laminated
body (Comparative example 1 in Table 1 mentioned later) of the electrically conductive film A
and the dielectric film which have not performed the smoothing process in FIG. 6 is shown. As
shown in Table 1 later, the surface roughness of the conductive film B is small without the
smoothing process (see Example 5). Therefore, as shown in FIG. 5, the conductive film B is
uniformly bonded to the dielectric film. On the other hand, the surface roughness of the
conductive film A not subjected to the smoothing process is large (see Comparative Example 1).
For this reason, as shown in FIG. 6, a cavity is generated at the interface with the dielectric film.
[0070]
<Measurement of Physical Properties of Conductive Film> [Volume Resistivity at Elongation] A
conductive film was cut out into a strip of 10 mm in width and 40 mm in length from the
prepared laminate, and used as a test piece. A pair of copper foils were arranged at intervals of
20 mm at both ends in the longitudinal direction of the test piece. Each of the copper foils was
connected to the terminals of the resistance measuring instrument. This test piece was elongated
in the length direction at a tensile speed of 100 mm / min according to a tensile test defined in
JIS K7127: 1999, and the electrical resistance was measured when it was elongated by 30%. The
measurement results are shown in Tables 2 and 3 below.
[0071]
[Elastic Modulus] The elastic modulus of the conductive film was calculated from the slope of the
linear region of the stress-elongation curve obtained in the tensile test in which the volume
resistivity at the time of elongation was measured. The measurement results are shown in Tables
14-04-2019
22
2 and 3 below.
[0072]
<Evaluation of Electrostrictive Element> A laminate prepared by bonding a conductive film to a
dielectric film when measuring the surface roughness of the conductive film (in the following
Table 1, Examples 1 to 6, 8 and Comparative Example The base material was peeled from 1 and
2) to produce an electrostrictive element. The dielectric breakdown strength, the relative
dielectric constant, the speaker performance, and the actuator performance of the produced
electrostrictive element were measured. The measurement results are summarized in Table 2
below.
[0073]
[Measurement of dielectric breakdown strength and relative dielectric constant] In the following
measurement, an electrostrictive element in which a 70 mm square conductive film (electrode)
was disposed on both sides in the thickness direction of the dielectric film was used.
[0074]
(1) Dielectric breakdown strength A DC voltage is applied stepwise between the electrodes of the
electrostrictive element, and the value obtained by dividing the voltage value immediately before
the dielectric film is broken by the film thickness of the dielectric film is the dielectric breakdown
strength. did.
The boosting condition was 5 V / μm every 15 seconds.
[0075]
(2) Relative Dielectric Constant An alternating voltage of 1 Vp-p, 1 MHz-0.1 Hz sweep was
applied between the electrodes of the electrostrictive element to measure the relative dielectric
constant of the dielectric film. In the measurement of relative permittivity, the electrostrictive
element is placed in the sample holder (Solatron, model 12962A), the permittivity measurement
interface (model, model 1296), and the frequency response analyzer (model 1255B). In
14-04-2019
23
combination.
[0076]
[Measurement of Speaker Performance] For the following measurement, an electrostrictive
element in which a circular conductive film (electrode) having a diameter of 50 mm was disposed
on both sides in the thickness direction of the dielectric film was used.
[0077]
(1) Resistance increase ratio of electrodes A DC bias voltage of 700 V was applied between the
electrodes of the electrostrictive element.
In this state, an alternating voltage of 120 Vp-p, 20 Hz-3 kHz (log sweep 30 second cycle) was
applied for 24 hours, and the electrical resistance in the surface direction of one of the electrodes
was measured. The electrical resistance of the electrodes was measured by placing terminals at
diametrically opposed positions. With the electric resistance of the electrode before the start of
measurement as the initial electric resistance, the resistance increase rate was calculated
according to the following formula (i). Resistance increase rate (%) = (electric resistance after 24
hours−initial electric resistance) / initial electric resistance × 100... (I) (2) A DC bias voltage of
700 V is applied between the electrodes of the sound piezoelectric strain element did. In this
state, an alternating voltage of 120 Vp-p was applied, and an average sound pressure in a
frequency range of 200 to 5000 Hz was measured at a point 30 cm away from the
electrostrictive element.
[0078]
[Measurement of Actuator Performance] In the following measurements, an electrostrictive
element was used in which a 30 mm long × 20 mm wide rectangular conductive film (electrode)
was disposed on both sides in the thickness direction of the dielectric film. First, the
electrostrictive element was attached to the measuring apparatus in a state where the dielectric
film was drawn in the longitudinal direction at a drawing rate of 25%. Next, a direct current
voltage was applied stepwise between the electrodes to measure the generated stress.
[0079]
14-04-2019
24
When a voltage is applied between the electrodes, the electrostatic attraction generated between
the electrodes compresses and stretches the dielectric film. Thereby, the stretching force in the
stretching direction (longitudinal direction) of the dielectric film is reduced. In this measurement,
the stretching force decreased before and after voltage application was measured by a load cell
and used as the generated stress.
[0080]
The measurement of the generated stress was repeated twice the ON-OFF cycle of the DC voltage
each time the voltage was raised by 5 V / μm. In the ON-OFF cycle, after applying a DC voltage
for 10 seconds, it was not applied for 15 seconds. The measurement of the generated stress was
performed until the dielectric film was broken.
[0081]
<Evaluation of Piezoelectric Actuator> As for the conductive film D (Example 7 in Table 1
described later, Example 7) in which the surface roughness was measured by pressure bonding
to a piezoelectric element at room temperature (as a connection member for connecting the used
piezoelectric element and wiring) The performance of the First, the configuration of the
manufactured piezoelectric actuator will be described. FIG. 7 shows a partial cross-sectional view
of the piezoelectric actuator.
[0082]
As shown in FIG. 7, the piezoelectric actuator 4 includes a piezoelectric element 40, a frame 44,
two wires 45a and 45b, and two connection members 46a and 46b. The piezoelectric element 40
is manufactured by Ariose Electronics Co. , Ltd., and has a disk shape with a diameter of 35 mm.
The piezoelectric element 40 includes a piezoelectric body 41, a metal deposition layer 42, and a
metal plate 43. The metal deposition layer 42 and the metal plate 43 function as electrodes. The
peripheral portion of the metal plate 43 is supported by the frame 44.
[0083]
14-04-2019
25
The wiring 45 a is disposed on the top surface of the frame 44. The wiring 45 b is disposed on
the lower surface of the frame 44. The wires 45 a and 45 b are each formed of the conductive
film B. A direct current power supply and an alternating current power supply are connected to
the not-shown end portions of the wires 45a and 45b.
[0084]
The metal deposition layer 42 and the wiring 45a are electrically connected by the connection
member 46a. The connection member 46a is in the form of a long strip. The connection member
46 a is made of the conductive film D. The connection member 46 a is bonded to the metal
deposition layer 42, the piezoelectric body 41, the frame 44, and the wiring 45 a. The metal plate
43 and the wiring 45b are electrically connected by the connection member 46b. The connecting
member 46 b is in the form of a long strip. The connection member 46 b is made of the
conductive film D. The connection member 46 b is bonded to the metal plate 43, the frame 44,
and the wiring 45 b.
[0085]
The piezoelectric actuator 4 was manufactured as follows. First, an assembly of the piezoelectric
element 40 and the frame 44 was produced. Next, on the upper surface of the frame 44, the
conductive film B as the wiring 45a was disposed. Similarly, the conductive film B as the wiring
45 b is disposed on the lower surface of the frame 44. Subsequently, the conductive films D as
the connection members 46a and 46b were disposed at predetermined positions on the upper
and lower surfaces of the assembly. Then, the conductive films B and D were crimped to the
assembled body by passing the assembled body on which the conductive films B and D are
disposed at 25 ° C. between the two rubber rollers, as in the case of producing the laminate. .
[0086]
Next, a method of measuring the performance of the connection member will be described. First,
a DC voltage of 3 kV / mm was applied for 15 minutes between the metal deposition layer 42
and the metal plate 43 to polarize the piezoelectric body 41. Next, the metal deposition layer 42
and the metal plate 43 In the meantime, an alternating voltage of 30 Vp-p, 20 Hz-3 kHz (log
14-04-2019
26
sweep 30 second cycle) was applied for 24 hours, and the electrical resistance between the metal
deposition layer 42 and the wiring 45 a was measured. With the electric resistance between the
metal deposition layer 42 and the wiring 45a before the start of the measurement as an initial
electric resistance, the resistance increase rate was calculated by the above-mentioned equation
(i). The measurement results are shown in Table 3 below.
[0087]
<Measurement Results> Table 1 shows the types of conductive films, the method of producing a
laminate, the measurement results of surface roughness, and the measurement results of noncontact rate. Table 2 shows the measurement results of the physical properties of the conductive
film and the evaluation results of the electrostrictive element. Table 3 shows the measurement
results of the physical properties of the conductive film and the evaluation results of the
piezoelectric actuator. In Table 1, adopted members and methods are indicated by 印. In Table 2,
the generated stress as the actuator performance is a value when the applied voltage is 60 V /
μm.
[0088]
Also, a sample using a commercially available solder ("SWF-10" manufactured by Engineer) or
silver paste ("Dotite (registered trademark) D-362" manufactured by Fujikura Kasei Co., Ltd.)
instead of the manufactured conductive film The measurement results of are shown as
Comparative Examples 3 to 5. About the sample of Comparative Examples 3-5, it produced as
follows.
[0089]
Comparative Example 3 In the measurement of the surface roughness and the non-contact rate,
instead of the conductive film D of Example 7, solder is applied to both sides in the thickness
direction of the piezoelectric element and cured to obtain conductive film / piezoelectric element
/ A laminate made of a conductive film was produced. In addition, when evaluating the
performance as a connecting member, the piezoelectric actuator was manufactured by
electrically connecting between the metal deposition layer 42 and the wiring 45a and between
the metal plate 43 and the wiring 45b by solder (the reference numeral denotes the front). See
Figure 7).
14-04-2019
27
[0090]
[Comparative Example 4] In the measurement of the surface roughness and the non-contact rate,
silver paste is applied to both sides in the thickness direction of the piezoelectric element in place
of the conductive film D of Example 7 and cured to obtain conductive film / piezoelectric element
A laminated body composed of a conductive film was produced. In addition, when evaluating the
performance as the connecting member, the piezoelectric actuator was manufactured by
electrically connecting between the metal deposition layer 42 and the wiring 45a and between
the metal plate 43 and the wiring 45b with silver paste (the reference numeral is See FIG. 7
above).
[0091]
Comparative Example 5 A silver paste was applied and cured on both sides in the thickness
direction of the dielectric film instead of the manufactured conductive film, to prepare a laminate
(electrostrictive element) consisting of conductive film / dielectric film / conductive film. .
[0092]
[Surface Roughness and Non-Contact Ratio] As shown in Examples 1 to 4 and 6 in Table 1, even
if the surface roughness of the conductive film is large, the surface roughness can be reduced by
performing a smoothing treatment. I was able to.
Thereby, as compared with Comparative Examples 1 and 2 in which the smoothing process was
not performed, the non-contact rate with the other member could be reduced. Further, in
Examples 5, 7 and 8, since the surface roughness is small without the smoothing process, the
non-contact rate with the other member is small.
[0093]
[Physical Properties of Conductive Film] As shown in Examples 1 to 8 in Tables 2 and 3, the
elastic modulus was small in all the conductive films, and the volume resistivity at the time of
elongation was also small. Thus, it was confirmed that the conductive films A to D were flexible
14-04-2019
28
and the electrical resistance did not easily increase even when stretched.
[0094]
[Dielectric breakdown strength and relative dielectric constant of electrostrictive element] As
shown in Table 2, in the electrostrictive elements of Examples 1 to 4, the dielectric breakdown
strength is higher than that of the electrostrictive element of Comparative Example 1. The
Similarly, in the electrostrictive element of Example 6, the dielectric breakdown strength was
higher than that of the electrostrictive element of Comparative Example 2. This is considered to
be because, in the electrostrictive element of the example, the bonding area between the
conductive film and the dielectric film is large, so that concentration of electric field is less likely
to occur as compared with the case of partial bonding. Moreover, in the electrostrictive elements
of Examples 1 to 4, the relative dielectric constant was larger than that of the electrostrictive
element of Comparative Example 1. Similarly, in the electrostrictive element of Example 6, the
relative dielectric constant was larger than that of the electrostrictive element of Comparative
Example 2. Essentially, if the components of the conductive film are the same, the relative
dielectric constants should also be the same. However, in the electrostrictive element of the
example, since the adhesion area between the conductive film and the dielectric film is large, it is
possible to store a large amount of electric charge, and the relative dielectric constant is
apparently increased.
[0095]
[Speaker Performance of Electrostrictive Element] As shown in Table 2, when the electrostrictive
element is operated as a speaker, in Examples 1 to 6 and 8 in comparison with Comparative
Examples 1, 2 and 5, The rate of increase in resistance decreased. This is because, in the
electrostrictive element of the example, the conductive film is flexible and the adhesion between
the conductive film and the dielectric film is high, so partial stress concentration is suppressed
and the conductive film is hard to break. it is conceivable that. Moreover, in Examples 1-6 and 8,
large sound pressure was obtained compared with Comparative Examples 1 and 2. This is
considered to be because, in the electrostrictive element of the example, the adhesion area
between the conductive film and the dielectric film is large, so a large amount of charge is stored
and the displacement amount of the dielectric film is large. In addition, the electrostrictive
element of the comparative example 5 using silver paste was not driven on the conditions of
sound pressure measurement.
14-04-2019
29
[0096]
[Actuator Performance of Electrostrictive Element] As shown in Table 2, when the electrostrictive
element is operated as an actuator, in Examples 1 to 6 and 8, the generated stress is larger as
compared with Comparative Examples 1 and 2. became. This is considered to be because, in the
electrostrictive element of the example, the adhesion area between the conductive film and the
dielectric film is large, so a large amount of charge is stored and the displacement amount of the
dielectric film is large. The electrostrictive element of Comparative Example 5 using silver paste
was not driven.
[0097]
[Performance as connecting member] As shown in Table 3, when the conductive film D is used as
the connecting member for connecting the piezoelectric element and the wiring (Example 7),
Comparative Example 3 using solder or silver paste Compared with 4, the resistance increase
rate between electrode-wiring became small. This is thought to be because the conductive film D
is flexible and the adhesion between the conductive film D and the electrode (metal deposition
layer) is high, so partial stress concentration is suppressed and the conductive film D is difficult
to break. Be
[0098]
The conductive film of the present invention is suitable for electrodes, wires, and connection
members for electrically connecting members in electronic parts such as transducers and flexible
wiring boards.
[0099]
1: Conductive tape member 2: Speaker (electronic component) 3: Substrate 4: Piezoelectric
actuator 10: Conductive film 11: first release sheet 12: second release sheet 20: electrostrictive
element 21a: upper frame, 21b: lower frame, 22: dielectric film, 23a, 23b: electrode (conductive
film), 30a, 30b: wiring, 31a, 31b: connecting member (conductive film), 40: piezoelectric element,
41 : Piezoelectric body, 42: metal deposition layer, 43: metal plate, 44: frame, 45a, 45b: wiring,
46a, 46b: connection member, 101: lower surface (smooth surface), 102: upper surface (smooth
surface), 210: Bolt, 230a: lower surface (smooth surface), 230b: upper surface (smooth surface),
231a, 231b: terminal portion, 310a, 310b: lower surface (smooth surface).
14-04-2019
30
Документ
Категория
Без категории
Просмотров
0
Размер файла
49 Кб
Теги
jp2015210927, description
1/--страниц
Пожаловаться на содержимое документа