(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2005/00994.02 A1
`(43) Pub. Date:
`May 12, 2005
`Nakanishi et al.
`
`US 2005.00994O2A1
`
`(54) TOUCH PANEL AND LIQUID CRYSTAL
`DISPLAY APPARATUS USING THE SAME
`(76) Inventors: Akira Nakanishi, Hirakata-shi (JP);
`Shigeyuki Fujii, Hirakata-shi (JP)
`Correspondence Address:
`WENDEROTH, LIND & PONACK, L.L.P.
`2033 K STREET N. W.
`SUTE 800
`WASHINGTON, DC 20006-1021 (US)
`(21) Appl. No.:
`10/967,268
`(22) Filed:
`Oct. 19, 2004
`(30)
`Foreign Application Priority Data
`
`Nov. 6, 2003 (JP)...................................... 2003-376865
`Jan. 8, 2004 (JP)...................................... 2004-0O2722
`
`Publication Classification
`
`(51) Int. Cl." ....................................................... G09G 5/00
`(52) U.S. Cl. .............................................................. 345/173
`
`(57)
`
`ABSTRACT
`
`The touch panel has a structure Such that a projection portion
`is provided on a Second transparent Substrate and a flexible
`printed-circuit board is bonded by thermocompression to the
`projection portion. By allowing width of a picture frame to
`be Smaller in other portions than the projection portion,
`downsizing and a lighter weight of a touch panel-carrying
`apparatus can be attained. By bonding a sheet member Such
`as a polarizing plate to a top face of the Second transparent
`Substrate excluding an area of the projection portion, StreSS
`to be applied from the sheet member to the thermocompres
`Sion-bonding portion of the FPC is reduced and, therefore,
`electric connection stability of the FPC can be enhanced.
`
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`Patent Application Publication May 12, 2005 Sheet 1 of 9
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`US 2005/0099.402 A1
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`Page 2 of 20
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`Patent Application Publication May 12, 2005 Sheet 2 of 9
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`US 2005/0099.402 A1
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`Patent Application Publication May 12, 2005 Sheet 3 of 9
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`Patent Application Publication May 12, 2005 Sheet 4 of 9
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`Patent Application Publication May 12, 2005 Sheet 5 of 9
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`US 2005/0099.402 A1
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`Patent Application Publication May 12, 2005 Sheet 6 of 9
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`US 2005/0099.402 A1
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`Patent Application Publication May 12, 2005 Sheet 7 of 9
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`US 2005/0099.402 A1
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`Patent Application Publication May 12, 2005 Sheet 8 of 9
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`US 2005/0099.402 A1
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`Page 9 of 20
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`Patent Application Publication May 12, 2005 Sheet 9 of 9
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`US 2005/0099.402 A1
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`Page 10 of 20
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`

`

`US 2005/00994O2 A1
`
`May 12, 2005
`
`TOUCH PANEL AND LIQUID CRYSTAL DISPLAY
`APPARATUS USING THE SAME
`
`TECHNICAL FIELD
`0001. The present invention relates to a touch panel
`which is provided on the Side of a display Surface of a liquid
`crystal display apparatus or the like and can input a Specified
`Signal by pressing the Surface corresponding to a displayed
`content with a pen or a finger, and also relates to a liquid
`crystal display apparatus provided with the touch panel.
`
`BACKGROUND OF THE INVENTION
`0002. In recent years, in portable apparatuses or elec
`tronic apparatuses which require menu Selections, the num
`ber of apparatuses which mount a touch panel and can input
`a specified Signal corresponding to a displayed content by
`pressing with a pen or a finger is increasing.
`0003) Among many types of touch panels, an analog-type
`touch panel comprising a resistive film which has been
`mainly used is explained with reference to Japanese Patent
`Laid-Open Application No. 2002-132449 using accompa
`nying drawings.
`0004.
`In order to facilitate understanding of a structure of
`the touch panel, the Structure is illustrated with a size
`expanded in the thickness-direction.
`0005 FIGS. 10 and 11 are drawings for explaining a
`conventional touch panel. The conventional touch panel
`comprises first transparent Substrate 1 and first transparent
`electrically conductive film 3 made of indium-tin oxide
`(hereinafter, referred to also as “ITO”) or the like formed on
`an entire top face of first transparent Substrate 1 by Sputter
`ing, for example. First transparent Substrate 1 is formed from
`a rectangular glass plate, a rectangular polycarbonate sheet
`or an acrylic resin sheet, or a plastic film Such as a biaxially
`oriented polyethylene terephthalate film or polycarbonate
`resin film which are processed into rectangular forms.
`0006. In FIG. 10, visible area boundary 6 of the touch
`panel is shown by a broken line. On first transparent
`electrically conductive film 3 inside visible area boundary 6,
`Small dot Spacers 5 made of an electrically insulating epoxy
`resin or the like are provided at Specified intervals.
`0007 When first transparent substrate 1 is a flexible film,
`substrate 1 may be laminated on a bottom face of substrate
`1 with a resin sheet Such as the polycarbonate resin Sheet or
`the acrylic resin sheet, or a glass sheet as a Support mean.
`0008 Second transparent electrically conductive film 4
`made of ITO or the like is formed by sputtering on an entire
`bottom face of Second transparent Substrate 2 which corre
`sponds to the operating Side of the touch panel. In order to
`allow Second transparent electrically conductive film 4 and
`first transparent electrically conductive film 3 to be opposed
`to each other with a specified interval inside visible area
`boundary 6, first transparent Substrate 1 and Second trans
`parent Substrate 2 are bonded to each other in picture frame
`form at a portion outside Visible area boundary 6.
`0009. In order to protect the touch panel from a scratch or
`the like which is liable to occur when it is operated by a pen
`or a finger, hard coat layer 7 having a pencil hardness of 3H
`made of acrylic resin is provided on the Side of a top face of
`Second transparent Substrate 2.
`
`0010. In an area outside visible area boundary 6, a wiring
`portion and electrode (hereinafter, referred to also as "wir
`ing/electrode pattern') 8 for Supplying a voltage to first
`transparent electrically conductive film 3, undercoat resist 9
`and overcoat resist 10 are formed; further, wiring/electrode
`pattern 12 for Supplying a Voltage to Second transparent
`electrically conductive film 4, undercoat resist 13 and over
`coat resist 14 are formed; and still further, adhesive layer 11
`is formed in a pattern for bonding first transparent Substrate
`1 and Second transparent Substrate 2. On this occasion,
`wiring/electrode patterns 8 and 12 are formed by first
`preparing an electrically conductive paint in which Silver
`powder is dispersed in a resin and, then, printing and drying
`the thus-prepared paint. Resists 9, 13, 10 or 14 are formed
`for insulating portions which are not necessary to be elec
`trically connected of wiring/electrode patterns 8 and 12.
`0011 FIG. 11 shows a structure in which transparent
`electrically conductive films 3 and 4 of first transparent
`Substrate 1 and Second transparent Substrate 2 respectively
`are not etched in a pattern. In the Structure, undercoat resist
`9 is formed between wiring/electrode pattern 8 and first
`transparent electrically conductive film 3, while undercoat
`resist 13 is formed between wiring/electrode pattern 12 and
`Second transparent electrically conductive film 4.
`0012. On the other hand, when a transparent electrically
`conductive film is formed in a pattern only in a necessary
`portion So that a portion Such as a wiring portion where
`electrical connection of each of wiring/electrode patterns 8
`and 12 is not required overlaps none of transparent electri
`cally conductive films 3 and 4, undercoat resists 9 and 13 can
`be omitted.
`0013 A flexible printed-circuit board (hereinafter,
`referred to also as “FPC) as shown in FIG. 11 transmits an
`output signal from each of first transparent electrically
`conductive film 3 and Second transparent electrically con
`ductive film 4 to an external circuit (not shown) and a tail
`portion thereof is connected to the external circuit.
`0014 FPC 15 involves substrate film 16, plurality of
`wiring patterns 17, on Substrate film 16, formed by a
`metal-plated copper foil or by a cured film of an electrically
`conductive paste in which Silver powder is dispersed, and
`cover lay 18 to cover a portion which is unnecessary for
`being exposed, for example, on a middle portion of wiring
`pattern 17. FPC 15 is connected to second transparent
`substrate 2 via anisotropic electrically conductive film 16 by
`means of thermocompression bonding. Wiring patterns 17 of
`FPC 15 thus subjected to the thermocompression bonding
`are electrically connected to any one of wiring/electrode
`patterns 8 and 12.
`0015. In FIG. 11, the touch panel in which FPC 15 is
`bonded by thermocompression only to Second transparent
`Substrate 2 is shown. However, as shown in FIGS. 12 to 15,
`a case in which FPC21 of a double-sided wiring type is used
`is known. A structure thereof is briefly described below.
`0016. As shown in FIG. 12, FPC21, which is interposed
`between first transparent Substrate 1 and Second transparent
`Substrate 2, has cut 211 in the center thereof. A left half of
`FPC21 from cut 211 is fixed to second transparent substrate
`2, while a right half of FPC 21 from cut 211 is fixed to first
`transparent substrate 1. FIG. 13 shows a cross-sectional
`view taken along line A-A explaining a fixed state of FPC21
`
`Page 11 of 20
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`

`

`US 2005/00994O2 A1
`
`May 12, 2005
`
`and second transparent Substrate 2, while FIG. 14 shows a
`croSS-Sectional view taken along line B-B explaining a fixed
`state of FPC 21 and first transparent Substrate 1. The
`conventional touch panel as shown in FIG. 13 is an example
`in which FPC 21 is bonded by thermocompression onto
`Second transparent Substrate 2 via anisotropic electrically
`conductive film 22, while the conventional touch panel as
`shown in FIG. 14 is an example in which FPC 21 is bonded
`onto first transparent Substrate 1 by thermocompression via
`anisotropic electrically conductive film 23. Wiring pattern
`24 formed on a bottom face of FPC 21 is electrically
`connected to wiring/electrode 8 of first transparent Substrate
`1 via anisotropic electrically conductive film 23, while it is
`connected to wiring pattern 24 on a top face thereof by
`means of through-hole electrode 25. By taking Such struc
`ture as described above, on the Side of the tail portion, wiring
`pattern 24 connected to first transparent electrically conduc
`tive film 3 and wiring pattern 26 (see FIG. 13) connected to
`Second transparent electrically conductive film 4 are col
`lected on the top face of FPC 21 and, then, are connected to
`an external circuit.
`0.017. In the conventional touch panel, there is a case in
`which a polarizing plate or a circularly polarizing plate is
`applied on Second transparent Substrate 2 and there is a
`Strong demand for improving optical characteristics thereof.
`Japanese Patent Laid-Open Application No. 2001-34418
`discloses a touch panel provided with a polarizing plate
`attached with a quarter-wave plate polarizer. The touch
`panel provided with the polarizing plate attached with the
`quarter-wave plate polarizer is now described with reference
`to FIGS 15 to 17.
`0018. In the touch panel as shown in FIGS. 15 to 17, in
`order to reduce reflection of external light, polarizing plate
`27 attached with a quarter-wave plate polarizer is provided
`on an entire Surface of Second transparent Substrate 2 via
`transparent adhesive layer 28 and hard coat layer 29 is
`provided on a top face of polarizing plate 27.
`0019. In the conventional touch panel using FPC 21 of
`the double-sided wiring type, FPC21 is connected to second
`transparent electrically conductive film 4 which becomes an
`input operation side via anisotropic electrically conductive
`film 22 and polarizing plate 27 is provided on a top face of
`Second transparent Substrate 2 including an area to which
`FPC 21 is bonded by thermocompression.
`0020. In the conventional touch panel, an area is required
`for bonding FPC 15 or FPC 21 on at least one of first
`transparent Substrate 1 and Second transparent Substrate 2 by
`thermocompression. As shown in FIGS. 10, 12 and 15, the
`area corresponds to W0xH0, where W0 is a width and H0 is
`a length. It has been in a mainstream to design Such that only
`the length H0 of a rectangular substrate of each of first
`transparent Substrate 1 and Second transparent Substrate 2 is
`expanded to Such an extent as necessary for providing FPC
`15 and FPC 21 thereon.
`0021
`However, in the aforementioned conventional
`touch panel, an area outside visible area boundary 6 of the
`touch panel, namely, an area of the picture frame, becomes
`large and, accordingly, there is a problem in that it becomes
`difficult to reduce a size and weight of an apparatus on which
`the touch panel is mounted.
`0022. Further, as shown in FIGS. 15 to 17, in the con
`ventional touch panel attached with polarizing plate 27,
`
`polarizing plate 27 is laminated on an entire face of Second
`transparent Substrate 2 including a portion thereof to which
`FPC 21 is bonded by thermocompression. For this account,
`in a high temperature atmosphere, a high temperature and
`high humidity atmosphere or a thermal shock test atmo
`Sphere, StreSS to be generated by a curling property or
`thermal expansion/contraction of polarizing plate 27 is
`likely to be transmitted to a portion to which FPC 21 is
`bonded by thermocompression. There is a problem in that
`the stress becomes a force for peeling FPC 21 bonded onto
`both first transparent Substrate 1 and Second transparent
`Substrate 2 off therefrom and it becomes difficult to consis
`tently maintain electrical connection of a portion thus
`bonded by thermocompression of FPC 21.
`0023. In order to relax the stress and the like, a structure
`in which cut is provided on FPC 21 or another structure in
`which a sheet having a Small thermal expansion coefficient
`for preventing curling is further provided on polarizing plate
`27 including an area of the picture frame has been proposed.
`However, in any one of the thus-proposed Structures, there
`is a problem in that, although an influence to the portion to
`which the FPC is bonded by thermocompression is reduced,
`a restriction on a design of wiring pattern is caused or
`another problem in that a production cost is increased.
`
`SUMMARY OF THE INVENTION
`0024. A touch panel according to the present invention
`comprises a first transparent Substrate having a first trans
`parent electrically conductive film formed on a top face
`thereof, a Second transparent Substrate, having a Second
`transparent electrically conductive film formed on a face
`opposite to the first transparent electrically conductive film,
`in which an outside of a visible area boundary is fixed by a
`adhesive layer and an inside thereof is held with a Specified
`Space from the first transparent Substrate, and a flexible
`printed-circuit board (FPC) bonded by thermocompression
`to at least one of the first transparent Substrate and the
`Second transparent Substrate. Further, at least one of the first
`transparent Substrate and the Second transparent Substrate
`has a projection portion to which the FPC is bonded by
`thermocompression. Still further, the touch panel can be
`prepared at a low cost Such that width of a frame thereof
`excluding the projection portion can be set narrow and,
`accordingly, have an effect which can contribute to reduction
`of a size and weight of an apparatus in which the touch panel
`is mounted. Furthermore, an apparatus in which the touch
`panel according to the present invention is mounted on the
`liquid crystal display device can realize down-sizing of a
`liquid crystal display apparatus.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`0025 FIG. 1 is a top plan view of a touch panel as a first
`embodiment according to the present invention;
`0026 FIG. 2 is a cross-sectional view taken along line
`A-A of FIG. 1;
`0027 FIG. 3 is a top plan view of a touch panel as a
`Second embodiment according to the present invention;
`0028 FIG. 4 is a cross-sectional view taken along line
`A-A of FIG. 3;
`0029 FIG. 5 is a cross-sectional view taken along line
`B-B of FIG. 3;
`
`Page 12 of 20
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`

`US 2005/00994O2 A1
`
`May 12, 2005
`
`0030 FIG. 6 is a perspective diagram showing a liquid
`crystal display apparatus of a third embodiment according to
`the present invention;
`0.031
`FIG. 7 is a cross-sectional view taken along line
`A-A of FIG. 6;
`0.032
`FIG. 8 is a perspective diagram showing a liquid
`crystal display apparatus of a fourth embodiment according
`to the present invention;
`0.033
`FIG. 9 is a cross-sectional view taken along line
`A-A of FIG. 8:
`0034 FIG. 10 is a top plan view of a conventional touch
`panel;
`FIG. 11 is a cross-sectional view taken along line
`0.035
`A-A of FIG. 10;
`0.036
`FIG. 12 is a top plan view of another configuration
`of an FPC in a conventional touch panel;
`0037 FIG. 13 is a cross-sectional view taken along line
`A-A of FIG. 12;
`0.038
`FIG. 14 is a cross-sectional view taken along line
`B-B of FIG. 12;
`0039 FIG. 15 is a top plan view of a touch panel attached
`with a conventional circularly polarizing plate;
`0040 FIG. 16 is a cross-sectional view taken along line
`A-A of FIG. 15; and
`0041
`FIG. 17 is a cross-sectional view taken along line
`B-B of FG 15.
`
`DESCRIPTION OF THE INVENTION
`0.042 A touch panel according to the present invention
`has a structure Such that a flexible printed-circuit board
`(hereinafter, referred to also as “FPC) for transmitting a
`led-out signal to an external circuit is bonded using ther
`mocompression to a projection portion provided on at least
`one of a first transparent Substrate and a Second transparent
`Substrate which constitute the touch panel. The touch panel
`can reduce width of a picture frame excluding the projection
`portion, can realize a low cost and, accordingly, can con
`tribute to reduction of a Size and weight of an apparatus on
`which the touch panel is mounted.
`0.043
`Further, the touch panel according to the present
`invention has a structure Such that a sheet member is applied
`on a top face of the Second transparent Substrate excluding
`the projection portion bonded with an FPC in thermocom
`pression manner. Still further, Since the touch panel accord
`ing to the present invention has a structure Such that, as
`fixing of the FPC using thermocompression is performed in
`the projection portion, not only it can contribute to the
`reduction of the size and weight of the apparatus on which
`it is mounted but also the sheet member is not lapped on the
`projection portion, a stable electric connection can be main
`tained even in a high temperature atmosphere, a high tem
`perature and high humidity atmosphere or a thermal shock
`test atmosphere. For example, when the sheet member is a
`polarizing plate or a circularly polarizing plate, the touch
`panel of the present invention prevents StreSS caused by a
`curling or a deformation by thermal expansion/contraction
`from being transmitted to a portion bonded with the FPC
`using thermocompression, accordingly, the touch panel
`
`according to the present invention can realize an article
`excellent in environmental resistance features at low cost.
`0044) When a polarizing plate, a circularly polarizing
`plate, an anti-reflection film, a hard coat film, a colored film
`or an indicating film is used as the sheet member, a function
`of each film can be added, to thereby realize a multi
`functional touch panel having a high performance.
`0045. In the touch panel according to the present inven
`tion, since an entire width of the FPC is fixed using
`thermocompression on a projection portion in the Second
`transparent Substrate which becomes an operating Side,
`fixation of the FPC is stabilized. Further, since the touch
`panel has a structure Such that a portion Subjected to the
`thermocompression bonding is the projection portion, when
`the thermocompression bonding is performed in a large area,
`an influence of transmission of overheat or pressure to a
`adhesive layer which bonds substrates to each other and
`fixes them can be Suppressed. Therefore, the touch panel can
`reduce occurrence of undulation within a visible area of the
`Second transparent Substrate which requires flexibility.
`0046. In a liquid crystal display apparatus provided with
`the touch panel according to the present invention, a size of
`an external shape of an approximate rectangle of each of the
`first transparent Substrate and the Second transparent Sub
`Strate excluding respective projection portions is allowed to
`be same with or less than that of a liquid crystal display
`device. For this account, the touch panel according to the
`present invention not only can contribute to reduction of size
`and weight of an apparatus on which a liquid crystal display
`apparatus attached with the touch panel (hereinafter, referred
`to also as “TTP-LCD”) but also has an action of contributing
`to improvement of reliability of environmental resistance
`features or the like or a cost reduction of the apparatus.
`0047. In the liquid crystal display apparatus provided
`with the touch panel according to the present invention, the
`touch panel is provided on all Surface of at least a liquid
`crystal display area on a top face of the liquid crystal display
`device. The present invention can reduce size and weight of
`an apparatus and improve environmental resistance features.
`AS air at an interface between the touch panel and the liquid
`crystal display device is eliminated, an apparatus in which a
`reflection of light at the interface is reduced and visibility is
`excellent can be realized.
`0048. In the liquid crystal display apparatus provided
`with the touch panel according to the present invention, the
`touch panel in which the polarizing plate or a circularly
`polarizing plate is used as a sheet member is provided on all
`Surface of at least a liquid crystal display area on a top face
`of the liquid crystal display device. On this occasion, the
`liquid crystal display device itself does not require an upper
`polarizing plate. Namely, Since an air layer is not present at
`an interface between the touch panel and the liquid crystal
`display device and the number of the polarizing plate as the
`TTP-LCD is reduced by one, the liquid crystal display
`apparatus can further reduce reflection of light and, accord
`ingly, brightness of the liquid crystal display is improved
`and the visibility is further enhanced.
`0049. Under these circumstance, according to the present
`invention, a low cost touch panel having a structure in which
`width of the picture frame area, excluding a projection
`portion which is a portion provided with the FPC, is allowed
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`to be narrow can be prepared. The touch panel as described
`above can contribute to reduction of size and weight of an
`apparatus on which the touch panel is mounted. Further, by
`bonding the sheet member Such as the polarizing plate to a
`portion excluding an area of the projection portion, a det
`rimental effect to a portion bonded with the FPC due to
`deformation of the sheet member thus provided is reduced,
`to thereby realize favorable environmental resistance fea
`tures. Namely, as an entire apparatus, there is a favorable
`effect in that the TTP-LCD which is inexpensive and has a
`favorable reliability and an excellent visibility can be real
`ized.
`0050 Embodiments according to the present invention
`are described with reference to FIGS. 1 to 9 below. In order
`to facilitate understanding of a structure, the Structure is
`illustrated with a size expanded in the direction of thickness.
`
`Embodiment 1
`FIGS. 1 and 2 are views explaining touch panel
`0051
`101 according to a first embodiment of the present invention.
`0.052 Touch panel 101 comprises first transparent Sub
`Strate 31 made of Soda glass processed in an approximately
`rectangular shape, Second transparent Substrate 32 having
`flexibility made of a biaxially oriented polyethylene tereph
`thalate film having a thickness of 188 um on the operational
`side and flexible printed-circuit board (hereinafter, referred
`to also as “FPC”) 45.
`0.053
`First transparent electrically conductive film 33
`made of indium tin oxide (hereinafter, referred to also as
`“ITO”) is formed on an entire top face of first transparent
`substrate 31 and, further, Small dot spacers 35 formed from
`insulating epoxy resin or the like are disposed at Specified
`intervals on first transparent electrically conductive film 33
`inside visible area boundary 36 shown by a dotted line.
`0.054 Second transparent substrate 32 comprises second
`transparent electrically conductive film 34 made from ITO
`and formed on an entire bottom face thereof. In an area
`inside visible area boundary 36 of the touch panel, a Space
`between first electrically conductive film 33 and second
`transparent electrically conductive film 34 is maintained to
`be in the range of from about 20 um to 500 um and, outside
`visible area boundary 36, first transparent substrate 31 and
`Second transparent Substrate 32 are bonded to each other.
`0.055 Second transparent substrate 32 has oblong projec
`tion portion 32A projecting outward from a middle portion
`of a Side thereof processed in an approximately rectangular
`shape and a size of the approximately rectangular shape is
`almost same with that of first transparent substrate 31.
`0056 First transparent substrate 31 and second transpar
`ent Substrate 32 are bonded to each other Such that outer
`circumferential portions of rectangular shapes of respective
`transparent Substrates are lapped one on the other in frame
`form. Namely, projection portion 32A of Second transparent
`Substrate 32 is configured Such that it is projected from
`rectangular-shaped portions of first transparent Substrate 31
`and Second transparent Substrate 32.
`0057. In order to protect the touch panel from a scratch or
`the like which is liable to occur when it is operated by a pen
`or a finger, hard coat layer 7 having a pencil hardness of 3H
`
`made of an acrylic resin is provided on the Side of a top face
`of Second transparent Substrate 32.
`0058. In an area outside visible area boundary 36, wiring
`portion and electrode for providing Voltage to transparent
`electrically conductive films 33 and 34 (hereinafter, referred
`to also as “wiring/electrode pattern”) 38 and 42 are formed
`by first preparing an electrically conductive paint in which
`Silver powder is dispersed in a resin and, then, printing and
`drying the thus-prepared paint. In wiring/electrode patterns
`38 and 42, in order to aim at insulating a portion which does
`not require an electrical connection, undercoat resists 39 and
`43 and overcoat resists 40 and 44 are each formed in a
`pattern State.
`0059 Wiring/electrode pattern 42 of second transparent
`substrate 32 extends outwardly to projection portion 32A
`and an end portion thereof is exposed on a Surface thereof
`for obtaining an electric connection.
`0060 Although not shown, wiring/electrode pattern 38
`on the side of first transparent substrate 31 is led out on the
`Side of Second transparent Substrate 32 and extends to
`projection portion 32A in a Same manner as in wiring/
`electrode pattern 42 and an end portion thereof is exposed on
`a Surface thereof.
`0061 Adhesive layer 41 for bonding first transparent
`Substrate 31 and Second transparent Substrate 32 to each
`other is also formed in an area outside visible area boundary
`36 in frame or picture frame form.
`0062 Flexible printed-circuit board (hereinafter, referred
`to also as “FPC) 45 for transmitting a led-out signal from
`first transparent electrically conductive film 33 and second
`transparent electrically conductive film 34 to an external
`circuit comprises base film 46 made of polyimide and a
`plurality of wiring patterns 47 which are each constituted by
`a gold-plated copper foil on base film 46, and a portion
`unnecessary of exposure of wiring pattern 47 is covered by
`cover lay 48 made of polyimide.
`0063 FPC 45 is bonded using thermocompression to a
`bottom face of projection portion 32A of Second transparent
`substrate 32 via anisotropic electrically conductive film 49
`involving, as a main component, an epoxy resin in which
`gold-plated resin beads are dispersed, and the tail portion
`thereof is connected to an external circuit (not shown).
`0064.
`In wiring pattern 47, wiring/electrode patterns 42
`and 38 thereof extend outwardly to- projection portion 32A
`and electrically connected to an exposed end portion via
`anisotropic electrically conductive film 49.
`0065. When connecting the tail portion of FPC 45 to the
`external circuit, projection portion 32A of Second transpar
`ent substrate 32 has flexibility and, accordingly, workability
`thereof is excellent. Further, since FPC 45 having no cut can
`be used, a cost increase of the FPC itself does not occur.
`0066. As Embodiment 1, when FPC 45 is thermocom
`pression bonded with the entire width thereof onto projec
`tion portion 32A in second transparent substrate 32 which
`becomes the operation side, the bonding of the FPC is
`Stabilized. Further, Since a portion Subjected to the thermo
`compression bonding is restricted to projection portion 32A,
`it is possible to put an restraint on an occurrence in which
`heating and preSSure application at the time of thermocom
`pression bonding give an influence to adhesive layer 41
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`which bonds first transparent substrate 31 and second trans
`parent substrate 32 to each other and fixes them. Therefore,
`second transparent substrate 32 which requires flexibility
`can reduce occurrence of an undulation within the Visible
`area and, accordingly, a touch panel of high quality can be
`obtained.
`0067. A method for manufacturing the touch panel
`according to the present Embodiment 1 is briefly described
`below.
`0068 Firstly, first transparent electrically conductive film
`33 made of ITO is formed on a surface of first transparent
`Substrate 31 by a Sputtering technique.
`0069. At the same time, a paint containing, as a main
`component, an acrylic resin is applied So as to form hard coat
`layer 37 on one face of second transparent Substrate 32 by
`using a roll coater and Second transparent electrically con
`ductive film 34 made of ITO is formed on the reverse face
`thereof by Sputtering.
`0070 Then, dot spacer 35 is formed in a portion inside
`visible area boundary 36, while undercoat resists 39 and 43,
`wiring/electrode patterns 38 and 42, overcoat resists 40 and
`44, adhesive layer 41 and the like are formed in respective
`Specified patterns in a portion outside visible a