U.S. patent application number 12/114201 was filed with the patent office on 2008-11-20 for antenna-embedded laminated glass and method for preparing the same.
This patent application is currently assigned to Asahi Glass Company, Limited. Invention is credited to Katsumi HISAEDA.
Application Number | 20080283173 12/114201 |
Document ID | / |
Family ID | 35431881 |
Filed Date | 2008-11-20 |
United States Patent
Application |
20080283173 |
Kind Code |
A1 |
HISAEDA; Katsumi |
November 20, 2008 |
ANTENNA-EMBEDDED LAMINATED GLASS AND METHOD FOR PREPARING THE
SAME
Abstract
The present invention provides a method for preparing an
antenna-embedded laminated glass with an antenna element sealed
between glass sheets, which is characterized to comprise forming
two or more glass sheets forming the laminated glass; bonding a
transfer film on a surface of one of the glass sheets by a bonding
strip, the transfer film including the bonding strip and a
conductive strip forming the antenna element; and press-bonding
glass sheet, through a intermediate film, to the surface of the one
glass sheet with the transfer film bonded thereto.
Inventors: |
HISAEDA; Katsumi; (Aichi,
JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
Asahi Glass Company,
Limited
Tokyo
JP
|
Family ID: |
35431881 |
Appl. No.: |
12/114201 |
Filed: |
May 2, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11261509 |
Oct 31, 2005 |
7379028 |
|
|
12114201 |
|
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Current U.S.
Class: |
156/102 |
Current CPC
Class: |
H01Q 1/38 20130101; H01Q
1/40 20130101; B32B 17/10761 20130101; B32B 17/10036 20130101; H01Q
1/1271 20130101; H01Q 1/1285 20130101 |
Class at
Publication: |
156/102 |
International
Class: |
B32B 37/12 20060101
B32B037/12 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 1, 2004 |
JP |
2004-318022 |
Claims
1. A method for preparing an antenna-embedded laminated glass,
comprising: forming a plurality of glass sheets in a curved shape;
laminating the glass sheets, an antenna element and an intermediate
film to form a laminated structure with the intermediate film
interposed between adjacent glass sheets, the intermediate film
affixing the antenna element and the adjacent glass sheets; and
press-bonding the laminated structure; wherein the laminating step
comprises forming the laminated structure by bonding a transfer
film to form a conductive strip on a surface of at least one of the
glass sheets by use of a bonding strip, and detaching a detachable
layer from said transfer film before performing the laminating step
so that only the conductive strip and the bonding strip remain on a
mating surface of the glass sheets, the transfer film including the
bonding strip and the conductive strip, wherein the detachable
layer is disposed on said transfer strip on a side of the bonding
strip, the conductive strip forming the antenna element, the
surface confronting the intermediate film.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of U.S. application Ser.
No. 11/261,509, filed Oct. 31, 2005, and claims benefit of priority
to Japanese patent application No. 2004-318022, filed on Nov. 1,
2004, the contents of both of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an antenna-embedded
laminated glass with an antenna element sealed between glass sheets
and a method for preparing the same.
[0004] 2. Description of the Related Art
[0005] Heretofore, an antenna sheet, which comprises a conductive
strip for an antenna element and an adhesive layer disposed on a
base sheet, has been known (see, e.g., JP-A-2001-119219). This
antenna sheet can function as a glass antenna by being bonded to a
surface of a glass sheet through the adhesive layer.
[0006] Such an antenna sheet is affixed to a surface of a glass
sheet in use. From this viewpoint, when such an antenna sheet is
bonded to, e.g., an interior surface of the front windshield of a
vehicle, the conductive strip needs to be covered with a
transparent protective layer. The protective layer is disposed for
the purpose of preventing the conductive strip from being damaged
and being disconnected by an external force. In some cases, a
boundary line between the protective layer and the glass sheet with
the antenna sheet affixed thereto is visible since the protective
layer has a different refractive index from the glass sheet, and
the protective layer covers the glass sheet over a relatively wide
area. For these reasons, such an antenna sheet has a problem of
poor appearance and a problem of obstructing a driver's view.
[0007] On the other hand, in an antenna-embedded laminated glass
with an antenna element sealed between glass sheets (see, e.g.,
JP-A-2-82701), an antenna element is protected by the glass sheets.
Even when such an antenna-embedded laminated glass is applied to an
automobile windshield, there is no problem, such as a poor
appearance caused by the provision of a protective layer in a
region except for the provision of the antenna element.
[0008] Such an antenna-embedded laminated glass is classified into
a print type wherein conductive paste is printed in a desired
pattern on an inner surface (mating surface) of a glass sheet to
from an antenna element, and an intermediate film embedded type
wherein an antenna wire is embedded in an intermediate film
(typically made of polyvinyl butyral) interposed between glass
sheets.
[0009] The above-mentioned print type cannot solve the problems
from the viewpoint of a poor appearance or the like since an
antenna pattern needs to have a wide line width in order to ensure
desired antenna performance because of the presence of large wire
resistance.
[0010] In this regard, the above-mentioned intermediate film
embedded type is advantageous from the viewpoint of poor appearance
or the like since an antenna wire having a small diameter can be
embedded in an intermediate film.
[0011] However, in the case of the above-mentioned intermediate
film embedded type, the intermediate film with an antenna wire
embedded therein expands or contracts in a heat treatment process,
such as press-bonding, to displace the position of the antenna wire
in some cases. This is because a laminated glass is produced by
sandwiching an intermediate film between two glass sheets, followed
by press-bonding and heat treatment. The tendency of such
positional displacement causes a problem from the viewpoint of
antenna performance. Additionally, there is a problem from the
viewpoint of the stability of antenna performance since the
tendency of such positional displacement is a major factor in
variations in the positions of the antenna patterns of respective
final products.
SUMMARY OF THE INVENTION
[0012] It is an object of the present invention to provide an
antenna-embedded laminated glass, which is capable of making it
difficult to cause the positional displacement of an antenna
pattern during production and of having a good appearance or the
like, and a method for preparing the same.
[0013] In order to solve the above-mentioned problem, according to
a first aspect of the present invention, there is provided a method
for preparing an antenna-embedded laminated glass comprising a
plurality of glass sheets affixed together through an intermediate
film to seal an antenna element between adjacent glass sheets, the
intermediate film comprising a resin; the method comprising forming
a plurality of glass sheets in a curved shape; laminating the glass
sheets, the antenna element and an intermediate film to form a
laminated structure; and press-bonding the glass sheets while
interposing the intermediate film between the adjacent glass
sheets; wherein the laminating step comprises forming the laminated
structure by bonding a transfer film to form a conductive film on a
surface of at least one of the glass sheets by use of a bonding
strip, the transfer film including the bonding strip and the
conductive strip, the conductive strip forming the antenna element,
the surface confronting the intermediate film.
[0014] In this aspect, the conductive strip may include a linear
portion formed in a desired pattern and having a line width (W)
satisfying the formula of 0.15.ltoreq.W.ltoreq.0.4 mm. The surface,
to which the transfer film is bonded, may comprise a convex surface
of the at least glass sheet having a curvature.
[0015] According to another aspect of the present invention, there
is provided an antenna-embedded laminated glass, comprising a
plurality of glass sheets affixed together through an intermediate
film to seal an antenna element between adjacent glass sheets, the
intermediate film comprising a resin; and the antenna element
comprising a conductive strip fixed to a surface of at least one of
the adjacent glass sheets by a bonding strip, the surface
confronting the intermediate film.
[0016] As explained, in accordance with the present invention, the
press-bonding process for press-bonding glass sheets with an
intermediate film sandwiched therebetween can be performed while
the conductive strip forming an antenna element is bonded to a
surface (mating surface) of a glass sheet by the adhesive strip.
Accordingly, it is possible to prevent the antenna element
(conductive strip) from causing positional displacement with
respect to the glass sheets by expansion or contraction of the
intermediate film during the press-bonding process and to produce
an antenna-embedded laminated glass having high positional
precision of the antenna element. When the conductive strip forming
the antenna element has a line width ranging from 0.15 to 0.4 mm,
it is possible to obtain an antenna-embedded laminated glass having
a good appearance or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a perspective view showing an application example
wherein an antenna-embedded laminated glass according to the
present invention is applied as the front windshield of an
automobile;
[0018] FIG. 2 is a flow sheet showing essential portions of a
process for producing an antenna-embedded laminated glass,
according to the present invention;
[0019] FIG. 3 is a schematic view showing the antenna sheet
according to an embodiment of the present invention;
[0020] FIG. 4 is a cross-sectional view taken along line A-A of
FIG. 3;
[0021] FIGS. 5A and 5B are schematic views explaining a conductive
strip transferring process;
[0022] FIG. 6A is a cross-sectional view taken along line A-A of
FIG. 3, showing the antenna sheet according to another
embodiment;
[0023] FIG. 6B is a cross-sectional view taken along line A-A of
FIG. 3 showing the antenna sheet according to another
embodiment;
[0024] FIG. 7 is a schematic view showing how a transfer film
material is stamped out when producing the antenna sheet showing in
FIG. 3 and FIG. 4;
[0025] FIG. 8 is a perspective view showing a first embodiment of
the electrode lead-out structure of the antenna element in an
antenna-embedded laminated glass produced by the present
invention;
[0026] FIG. 9 is a cross-sectional view taken along line X-X of
FIG. 8;
[0027] FIG. 10 is a perspective view showing a second embodiment of
the electrode lead-out structure of the antenna element in an
antenna-embedded laminated glass produced by the present
invention;
[0028] FIG. 11 is showing the antenna sheet corresponding to the
embodiment shown in FIG. 10; and
[0029] FIG. 12 is a cross-sectional view taken along line X-X of
FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] Now, preferred embodiments of the present invention will be
described, referring to the accompanying drawings.
[0031] FIG. 1 shows an application example of an antenna-embedded
laminated glass according to the present invention. Although the
antenna-embedded laminated glass 10 is normally used as the front
windshield of an automobile as in this application example, the
laminated glass may be used as a side windshield or the rear
windshield of an automobile.
[0032] The laminated glass 10 is produced by press-bonding a
plurality of glass sheets 12 with an intermediate film 14
interposed therebetween (see FIG. 8). The intermediate film 14 may
be made of, e.g., polyvinyl butyral (PVB).
[0033] Glass sheets 12 forming the laminated glass 10 have an
antenna element 20 sealed therebetween as stated later. The antenna
element 20 may be formed in a desired pattern as shown in FIG. 1
and receive, e.g., an electromagnetic wave from a television
station or a radio station, an electromagnetic wave from a
cell-phone, or an electromagnetic wave from a satellite. In this
application example, the antenna element 20 is protected by the
glass sheets 12 since the antenna element 20 is sealed between the
glass sheets 12.
[0034] FIG. 2 is a flow sheet showing essential portions of a
process for producing an antenna-embedded laminated glass,
according to the present invention. Now, explanation will be made
about a case wherein the laminated glass 20 comprises two glass
sheets 12, and wherein the glass sheet that is located on an
exterior side when the laminated glass is mounted to a vehicle is
indicated by reference numeral 12a, and the glass that is located
on an interior side is indicated by reference numeral 12b.
[0035] As shown in FIG. 2, the process for producing a laminated
glass, according to this embodiment comprises a glass sheets
forming process 100, a conductive strip transferring process 120
and a glass sheets laminating process 140.
[0036] In the glass sheets forming process 100, two basic glass
sheets are independently subjected to cutting and chamfering steps
(Step 101), and cleaning and drying steps (Step 102). In order to
conceal an eyesore, a print is applied to an edge portion of the
basic glass sheet (interior glass sheet) that forms the glass sheet
12b on the interior side of the two basic glass sheets (Step 103).
The print may be applied to an edge portion of the exterior glass
sheet 12a or may be applied to each of the exterior glass sheet and
the interior glass sheet. After that, both glass sheets are
overlapped with each other (Step 104), and both glass sheets have
edge portions carried on a frame, being overlapped each other.
Next, the glass sheets thus overlapped are heated to a temperature
of not lower than the softening point and are bent in a curved
shape by gravity (Step 105). Then, both sheets are subjected to
annealing (Step 106), and both sheets are separated from each other
(Step 107). Thus, the glass sheets 12a and 12b are provided with
surfaces having substantially the same curvatures as each other.
The glass sheets 12a and 12b are subsequently and independently
subjected to washing and drying steps (Step 108) and are
transferred into the conductive strip transferring process 120.
[0037] In the conductive strip transferring process 120, an antenna
sheet 30 is affixed on an exterior surface of the glass sheet 12b.
The exterior surface of the glass sheet 12b is an exterior surface
of the interior glass sheet 12b as stated earlier, that is to say,
a surface of the glass sheet 12b confronting the glass sheet 12a
when being laminated with the glass sheet 12b (hereinbelow,
referred to as "the mating surface 13a".
[0038] As shown in FIG. 3, the antenna sheet 30 is a sheet material
having a desired shape. As shown in FIG. 4 (showing a
cross-sectional view taken along line A-A of FIG. 3), the antenna
sheet 30 comprises a transfer film material containing a conductive
strip 32 for forming at least one antenna element 20 and a bonding
strip 34. The conductive strip 32 and the bonding strip 34 are
disposed between a first detachable layer (mount) 31a formed in the
desired shape and a second detachable layer (protective film) 31b.
The first detachable layer is a mount, which serves to hold the
antenna pattern formed by the conductive strip 32 until the
conductive strip 32 and the bonding strip 34 are fixed to the
mating surface 13a of the glass sheet 12b. Since the transfer film
material includes the mount, it is possible not only to handle and
fix the conductive strip but also to prevent the antenna pattern
from being deformed. The second detachable layer is a protective
film, which serves to protect the conductive strip until the
conductive strip 32 and the bonding strip 34 are fixed to the
mating surface 13a of the glass sheet 12b. Since the transfer film
material includes the protective film, it is possible to prevent
the antenna pattern from being deformed or broken by an external
force. From this viewpoint, it is preferred that the second
detachable layer be detached immediately before the transfer film
material is disposed on and fixed to the mating surface 13b. The
conductive strip 32 and the second detachable layer 31b have an
adhesive layer 35 interposed therebetween. The adhesive layer 35
bonds the conductive strip 32 to the second detachable layer 31b by
an easily-detachable adhesive force. The first detachable layer 31a
has a slit 50 formed in each region in consideration of workability
in detaching operation.
[0039] In the conductive strip transferring process 120, the first
detachable layer (mount) 31a is first detached from the antenna
sheet 30 (Step 121), and the antenna sheet 30 with the first
detachable layer detached therefrom is located at and bonded to a
desired position on the mating surface 13a of the glass sheet 12b
(Step 122). At that time, the conductive strip 32 is bonded to the
mating surface 13a of the glass sheet 12b by the bonding strip 34
as shown in FIG. 5A. In order to ensure that the bonding strip 34
and the mating surface 13a are bonded together, the antenna sheet
30 may be pressed against the mating surface 13a of the glass sheet
12b.
[0040] Next, the second detachable layer (protective film) 31b is
detached along with the adhesive layer 35 from the conductive strip
32 as shown in FIG. 5B (Step 123). Thus, the first detachable layer
31a and the second detachable layer 31b are removed, and only the
conductive strip 32 and the bonding strip 34 remain on the mating
surface 13a of the glass sheet 12b. It is clear that the adhesive
force between the adhesive layer 35 and the conductive strip 32 is
adjusted to be sufficiently smaller than the bonding force of the
bonding strip 34. The adhesive force thus adjusted is set to have a
degree to prevent the conductive strip 32 from being detached along
with the bonding strip 34 from the mating surface 13a of the glass
sheet 12b or the conductive strip 32 from being detached from the
bonding strip 34 when detaching the second detachable layer
31b.
[0041] After that, as required, treatment, such as bending an end
portion of the antenna element 20 from an edge portion of the glass
sheet 12b (see FIG. 8), may be performed for connection of the
antenna element 20 (conductive strip 32) to an electrode 40 (see
FIG. 8) (Step 124).
[0042] When the process 120 for bonding the antenna sheet to the
glass sheet 12b is completed as stated earlier, the process
proceeds to the glass sheets laminating process 140 to laminate the
glass sheet 12b and the glass sheet 12a.
[0043] In the glass sheets laminating process 140, the glass
sheets, the antenna element and the intermediate film for affixing
the antenna element and the glass sheets are formed into a
laminated structure, interposing the intermediate film between the
glass sheets, and the glass sheets, the antenna element and the
intermediate film are press-bonded to obtain a laminated glass.
Specifically, the intermediate film 14 is first cut out into
substantially the same shape as the glass sheets 12a and 12b, being
subjected to a washing step and a film cutting step (Steps 141 and
142), and the intermediate film thus cut out is interposed into
between the glass sheet 12a and 12b (Step 143). Thus, the
intermediate film 14 is interposed between the mating surface 13a
of the glass sheet 12b with the above-mentioned conductive strip 32
bonded thereto and the mating surface of the glass sheet 12a,
providing the laminated structure. Next, both glass sheets 12a and
12b are preliminarily press-bonded (Step 144), and both glass
sheets are primarily press-bonded together by an autoclave
(pressure vessel) (Step 145). As a result, the bonding surfaces
between the intermediate film 14 and each of both glass sheets 12a
and 12b are completely evacuated and melt-bonded, and thus the
laminated glass 10 is completed.
[0044] In the process wherein the air on the interface between the
intermediate film 14 and each of the glass sheets is evacuated to
completely press-bond both glass sheets 12a and 12b, not only a
pressure but also heat is applied to the intermediate film.
Accordingly, the intermediate film 14 is contracted between both
glass sheets 12a and 12b. For this reason, in the case of a
structure wherein the antenna wire is disposed on the side of the
intermediate film 14, or a structure wherein a second film with an
antenna pattern printed thereon is interposed between the
intermediate film 14 and a glass sheet 12, the antenna wire or the
second film is likely to cause positional displacement by expansion
or contraction of the intermediate film 14.
[0045] On the other hand, in this embodiment, the antenna element
20 is bonded as the conductive strip 32 to the mating surface 13a
of the glass sheet 12b by the bonding strip 34 as stated earlier.
Accordingly, the conductive strip 32 is prevented from being
shifted with respect to the mating surface 13a of the glass sheet
12b by expansion or contraction of the intermediate film 14. In
accordance with this embodiment, there is no possibility that the
antenna element 20 is subjected to positional displacement with
respect to the glass sheet 12b during production. As a result, the
antenna element (antenna pattern) 20 can have positional precision
improved to be provided with desired antenna performance. The
variations in the positions of antenna elements (antenna patterns)
20 that can be caused in respective final products can be
remarkably reduced to make antenna performance stable.
[0046] The positional precision of the antenna element (antenna
pattern) 20 has influences not only on the electrical connection
with a vehicle side but also the positional relationship with a
peripheral member serving as ground when the antenna element is
mounted to a vehicle. For this reason, the positional precision of
the antenna element 20 also has an influence on antenna performance
in some cases. Specifically, when the antenna element 20 is mounted
to the front windshield of an automobile, the antenna element is
influenced by the positional relationship with a body pillar in
some cases.
[0047] The influence on the antenna performance is significant, in
particular, when the antenna element 20 serves as receiving an
electromagnetic wave having a high frequency, such as digital
broadcasting. From this viewpoint, the antenna-embedded laminated
glass 10 produced by this embodiment can exhibit desired antenna
performance with variations in respective final products minimized
even when the laminated glass is applied to such an
application.
[0048] Additionally, the antenna sheet 30 (the conductive strip 32)
is bonded to the mating surface 13a of the glass sheet 12b, which
is a convex side, in this embodiment. In this case, a tension is
placed on the antenna sheet 30 at the time of affixture as opposed
to a case the antenna sheet 30 is affixed to a concave side (for
example, the interior surface of the glass sheet 12a). Accordingly,
the antenna sheet 30 is unlikely to be wrinkled, providing good
workability. Additionally, the weather resistance of the antenna
element 20 is improved since the conductive strip 32 is located on
a position closer to the interior of the vehicle than the
intermediate film 14 having a UV cutting function.
[0049] Although the conductive strip transferring process 120 may
be manually performed by an operator in this embodiment, this
process may be automated, using, e.g., a robot. The antenna sheet
30 does not always need to be delivered, being separated from other
antenna sheets. As another delivery mode, plural antenna sheets 30,
which are separable from each other, are continuously wound on a
roll, and the respective antenna sheets may be separated from each
other, being unwound from the roll on the production line.
[0050] FIGS. 6A and 6B show other embodiments of the antenna sheet
30, which are different from the embodiment shown in FIG. 4, and
these figures correspond to the cross-sectional view taken along
line A-A of FIG. 3.
[0051] The antenna sheets 30 shown in FIG. 6A includes a dark strip
37 laminated on an interior side of the conductive strip 32 through
a bonding strip. The dark strip 37 comprises a black paint having a
low reflectance and is disposed so as to make the conductive strip
32 invisible from a vehicle interior side in terms of good
appearance. The dark strip 37 functions to protect the conductive
strip 32 to increase the strength and the stability of the
conductive strip. The antenna sheet 30 shown in FIG. 6B includes
dark strips 37 disposed both sides of the conductive strip 32. As
shown in these figures, the antenna sheet 30 may appropriately
include various kinds of layers in addition to the conductive strip
32 and the bonding strip 34. The thickness of each of the strips
and the layers may be appropriately set. For example, the transfer
film material shown in FIG. 6B may have a total thickness D of
about 0.3 mm. These figures show embodiments wherein a dark strip
or dark strips using a black paint are applied by printing for
concealing an eyesore. However, the color of the dark strip or the
dark strips is not limited to black. Any other colors, such as gray
or dark brown, are acceptable as long as a selected color can
shield visual light or ultraviolet light.
[0052] The conductive strip 32 may be made of soft copper. The
bonding strip 34 or the adhesive layer 35 may be made of an acrylic
adhesive material. The second detachable layer may be made of a
polyester film. The first detachable layer 31a may be made of
woodfree paper having a single side polylaminated or a resin sheet
(such as a PET sheet), which is treated so as to have a detachable
property.
[0053] The pattern of each of the antenna elements 20 as shown in
FIG. 3 may be formed by using a press to stamp, with desired dies,
a transfer film material comprising various kinds of layers and the
strips. FIG. 7 shows how the transfer film material is stamped when
preparing the antenna sheet 30 shown in FIG. 4. In this case, the
transfer film material comprising the conductive strip 32 and the
bonding strip 34 are stamped so as to have a line width W by the
upper and lower die.
[0054] The line width W of the conductive strip 32 satisfies the
formula of 0.15.ltoreq.W.ltoreq.0.4 mm, preferably the formula of
0.2.ltoreq.W.ltoreq.0.3 mm, in an antenna pattern portion as a
portion excluding edge portions, an electrode portion or the like.
This arrangement can provide the laminated glass with a good
appearance and is advantageous from the viewpoint that the antenna
element is prevented from obstructing a driver's view when the
laminated glass is used as an automobile windshield. Explanation of
this embodiment has been made about a case wherein the conductive
strip 32 is formed by stamping a transfer film material. However,
the conductive strip may be formed by printing conductive paste or
using an antenna wire. The bonding strip may be formed by being
laminated on the conductive strip before forming the pattern and
the bonding strip or may be formed on a surface of the conductive
strip after forming the pattern by the conductive strip.
[0055] The conductive strip 32 and the bonding strip 34 thus
stamped are combined with both of the first detachable layer 31a
and a transfer film material comprising the second detachable layer
31b and the adhesive layer 35, and the combination is passed
between rollers to complete the antenna sheet 30.
[0056] FIG. 8 is a perspective view of a first embodiment of the
electrode lead-out structure of the antenna element 20 in an
antenna-embedded laminated glass 10 produced according to the
above-mentioned embodiments.
[0057] This embodiment is related to an antenna-embedded laminated
glass 10, which is produced by using the antenna sheet 30 shown in
FIG. 3. In this embodiment, the electrode lead-out portion of each
of the antenna elements 20 is formed from a portion of the
conductive strip 32 having a relatively large line width W. In
other words, the conductive strips 32 in this embodiment are
stamped so that each of the conductive strips comprises a thin
linear portion 32a having a line width W satisfying the equation of
0.15.ltoreq.W.ltoreq.0.4 mm and an extension 32b made of the same
material as the thin linear portion and having a relatively larger
line width and a length.
[0058] FIG. 9 is a cross-sectional view taken along line X-X of
FIG. 8. The thin linear portion 32a and a portion of the extension
32b are bonded to the mating surface 13a of the glass sheet 12b by
the bonding strip 34 as stated earlier. As seen from FIG. 9, the
conductive strip 32 bonded to the glass sheet 12b by the bonding
strip 34 is embedded in the intermediate film 14 after the primary
press-bonding process is completed.
[0059] The extension 32b is folded at an edge portion of the glass
sheet 12b toward an opposite surface 13b of the glass sheet 12b.
This folding step is performed by folding a leading portion of the
antenna sheet 30 toward the opposite surface 13b of the glass sheet
12b along a folding line H as shown in FIG. 3 and affixing an end
portion of the antenna sheet to the opposite surface in the
conductive strip transferring process 120.
[0060] An end of the extension 32b is connected to an electrode 40,
which is formed on the opposite surface 13b of the glass sheet 12
by, e.g., printing. The connection between the edge of the
extension 32b and the electrode 40 is made by soldering after the
above-mentioned primary press-bonding treatment (Step 145) has been
completed.
[0061] The electrode 40 is connected to an amplifier (not shown)
through a wire (not shown), the amplifier being disposed on a
vehicle side for amplifying an electromagnetic wave received by the
antenna element 20. When the antenna is activated, an
electromagnetic wave received by the antenna element 20 is taken
out through the electrode 40, is subjected to processing (such as
amplification) as required and is supplied to an in-vehicle media
system, such as a TV receiver. The electromagnetic wave received by
the antenna element 20 may be wirelessly transmitted an in-vehicle
media system through a Bluetooth receiver or a wireless LAN
receiver connected the electrode 40.
[0062] FIG. 10 is a perspective view showing a second embodiment of
the electrode lead-out structure of the antenna element 20 in an
antenna-embedded laminated glass 10 produced according to the
above-mentioned embodiment.
[0063] In this embodiment, each of the antenna elements 20 has an
electrode per se comprising a portion of the conductive strip 32
formed in a desired shape. In other words, the conductive strips 32
in this embodiment are stamped so that each of the conductive
strips comprises a thin linear portion 32a having a constant line
width W satisfying the formula of 0.15.ltoreq.W.ltoreq.0.4 mm and
an electrode 32c having a region formed in a desired shape. FIG. 11
shows the antenna sheet 30 corresponding to this embodiment.
[0064] FIG. 12 is a cross-sectional view taken along line X-X of
FIG. 10. The thin linear portion 32a and the electrode 32c are
bonded to the mating surface 13a of the glass sheet 12b by the
bonding strip 34 as stated earlier. In the embodiment shown in FIG.
12, an antenna sheet 30 having a laminated structure as shown in
FIG. 6A as stated earlier is used. Thus, the electrode 32c is
sealed as the conductive strip 32 between both glass sheets 12a and
12b of a laminated glass 10.
[0065] The opposite surface 13b of the glass sheet 12b has an
electrode 40 disposed at a position to confront the electrode 32c
by, e.g., printing. Thus, the electrode 40 and its corresponding
electrode 32c can be connected through static capacitive coupling
(electromagnetic coupling). The electrode 40 is connected to an
in-vehicle amplifier (not shown) through a wire (not shown), the
amplifier serving as amplifying an electromagnetic wave received by
the antenna element 20. When the antenna is activated, an
electromagnetic wave received by the antenna element 20 is taken
out through the static capacitive coupling between the electrode 40
and the electrode 32, is subjected to processing (such as
amplification) as required and is supplied to an in-vehicle media
system, such as a TV receiver, through an external wire. An
electromagnetic wave received by the antenna element 20 may be
wirelessly transmitted to an in-vehicle media system through a
Bluetooth receiver or a wireless LAN receiver connected to the
electrodes 40.
[0066] In this embodiment, it is not necessary to connect each of
the electrodes 40 and the antenna element 20 on the laminated glass
10 by soldering, and it is possible to connect an in-vehicle media
system and the antenna element 20 through static capacitive
coupling. Accordingly, it is possible to avoid inconvenience that a
heat stress is generated in the glass sheets 12a and 12b because of
heat generated during soldering.
[0067] In this embodiment, the electrodes 32c are disposed on the
mating surfaces 13a of the interior glass sheet 12b. Accordingly,
the positional precision in this embodiment is better with respect
to the positional displacement between the electrode 32c and the
electrode 40 in each couple in comparison with a case the
electrodes 32c are disposed on an interior surface of the exterior
glass sheet 12a. Additionally, in this embodiment, the electrodes
32c are bonded to the glass sheet 12b as stated earlier.
Accordingly, it is possible to obtain static capacitive coupling
having high reliability since the positional displacement between
an electrode 32c and its coupled electrode 40 is difficult to be
caused by influence of expansion or contraction of the intermediate
film 14. Although preferred embodiments of the present invention
have been described in detail, the present invention is not limited
to the above-mentioned embodiments. It is to be understood that
various modifications or changes are applicable to the
above-mentioned embodiments without departing from the sprit and
the scope of the present invention.
[0068] Although the above-mentioned embodiments have been described
in a case wherein the antenna sheet 30 is disposed between the
intermediate film 14 and the mating surface 13a of the interior
glass sheet 12b, it is to be understood that the present invention
does not exclude a structure wherein the antenna sheet 30 is
disposed between the intermediate film 14 and the exterior glass
sheet 12a. Even in the latter case, it is possible to obtain an
advantage that the antenna element 20 can be bonded and disposed
with high positional precision in the laminated glass 10.
[0069] The intermediate film 14 cannot always comprise a single
layer. The intermediate film may comprise plural layers between the
two glass sheets 12. The intermediate film 14 may have another
function, such as a sound isolation function or heat reflection
function.
[0070] The entire disclosure of Japanese Patent Application No.
2004-318022 filed on Nov. 1, 2004 including specification, claims,
drawings and summary is incorporated herein by reference in its
entirety.
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