JP2015199801A METHOD FOR PRODUCING TRANSPARENT SURFACE MATERIAL HAVING
`TACKY ADHESIVE LAYER, TRANSPARENT SURFACE MATERIAL HAVING TACKY
`ADHESIVE LAYER, AND DOUBLE-SIDED TACKY-ADHESIVE FILM
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`Data originating from sources other than the EPO may not be accurate, complete, or up to date.
`
`The wording below is an initial machine translation of the original publication. To generate a version using the
`latest translation technology, go to the original language text and use Patent Translate.
`
`Production method of transparent surface material with adhesive layer, transparent surface material with
`adhesive layer, double-sided adhesive film
`
`[0001] The present invention relates to a method for producing a transparent surface material with an adhesive
`layer, a transparent surface material with an adhesive layer, and a double-sided adhesivefilm.
`
`[0002] DESCRIPTION OF RELATED ARTThe display apparatus by which the surface of the display panel
`(object to be bonded) was protected by the transparent surface material is known conventionally (for example,
`refer patent document 1). In a display device in which a display panel is protected by a transparent surface
`material, a transparent surface material with an adhesive layer having an adhesive layer attached to one surface
`of the transparent surface material is bonded to the surface of the display panel via the adhesive layer. It
`manufactures by bonding the display panel with the adhesion layer by which the adhesion layer was stuck on
`one surface of the display panel on the surface of a transparent surface material through the adhesion layer. In
`the following description, the case where the transparent surface material to which the adhesive layer is attached
`is attached to the display panel will be described as an example.
`
`[0003] In addition, "transparent" said here means having transparency with respectto visible light generally.
`Therefore, the “transparent surface material” also means a surface material having optical transparency to
`visible light.
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`FEIBRABRHES 201171489905
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`[0004]
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`[0005] By the way, when manufacturing the transparent surface material with the adhesion layer mentioned
`above, a double-sided adhesive film in which separators (also referred to as a protective film and a release film)
`are peelably attached to both sides of the adhesion layer is prepared in advance Do. Andafter peeling one
`separator from this double-sided adhesive film, the transparent surface material can be efficiently manufactured
`by sticking a transparent surface material on the surface of an adhesive layer. Moreover,in the case of this
`manufacturing method, it can respond to the further enlargementof the transparent surface material with an
`adhesion layer. Furthermore, if this manufacturing method is performed by a continuousprocess, the production
`efficiency of the transparent layer with the adhesive layer can be enhanced.
`
`[0006] An aspect of the present invention aims to provide a method for producing a transparent surface material
`with a pressure-sensitive adhesive layer, a transparent surface material with a pressure-sensitive adhesive layer,
`and a double-sided pressure-sensitive adhesive film, which can improve productivity.
`
`[0007] In order to achieve the above object, in the method for producing a transparent surface material with an
`adhesive layer according to one aspect of the present invention, an adhesive layer and a metal layer are
`releasably adhered to one surface of the adhesive layer. A double-sided adhesive film comprising a first
`separator provided and a second separator releasably attached to the other surface of the adhesive layeris
`irradiated with laser light from the second separator side, Cutting the second separator and the adhesive layer
`into a sticking area and a non-sticking area, peeling the second separator in the sticking area from the adhesive
`layer, and the second separator And attaching the adhesive area of the pressure-sensitive adhesive layer to the
`transparent surface material, and cutting the double-sided adhesive film at the non-adhesive area.
`
`[0008] Moreover, the transparent surface material with the adhesion layer which concerns on one aspectofthis
`invention can peel on one surface of a transparent surface material, the 1st adhesion layer provided on the said
`transparent surface material, and the said 1st adhesion layer. And a first adhesive layer provided with a metal
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`layer, and the first adhesive layer and a second adhesive layer separated from thefirst adhesive layer through a
`groove and one surface of whichis attachedto the first separator. And a second separator attached to the other
`surface of the second adhesive layer.
`
`[0009] Moreover, the double-sided pressure-sensitive adhesive film according to one aspect of the present
`invention comprises a pressure-sensitive adhesive layer, a first separator attached releasably to one surface of
`the pressure-sensitive adhesive layer, and a metal layer provided thereon; A second separator releasably attached
`to the other surface is provided, and the second separator and the adhesive layer are each cut into a plurality of
`attached areas and a non-adheredarea..
`
`[0010] As described above, according to one aspect of the present invention, it is possible to provide a method
`for producing a transparent surface material with a pressure-sensitive adhesive layer, a transparent surface
`material with a pressure-sensitive adhesive layer, and a double-sided pressure-sensitive adhesive film that can
`improve productivity.
`
`[0011] It is sectional drawing which showsschematic structure of the transparent surface material with the
`adhesion layer which concerns on one Embodimentofthis invention.It is sectional drawing which shows
`schematic structure of a display apparatus provided with the display panel in whichthe said transparent layer
`with the adhesion layer shown in FIG. 1 was bonded. BRIEF DESCRIPTION OF THE DRAWINGSItis
`sectional drawing which shows schematic structure of the double-sided adhesive film which concerns on one
`Embodimentofthis invention. It is a perspective view which shows the raw fabric of a double-sided adhesive
`film. It is a schematic diagram which showsschematic structure of the manufacturing apparatus used for
`manufacture of the transparent surface material with the adhesion layer shown in FIG. It is a figure for
`demonstrating the manufacturing processof the transparent surface material with the adhesion layer shown in
`FIG. 1, and is a perspective view which shows the process of giving a cutting process with respect to an original
`fabric. It is a figure for demonstrating the manufacturing process of the transparent surface material with the
`adhesion layer shownin FIG. 1, and is sectional drawing which shows the state which cut-processed with
`respect to the original fabric. It is a figure for demonstrating each manufacturing process of the transparent
`surface material with an adhesion layer shownin FIG. 1, and is a perspective view which shows the process of
`peeling the 2nd separator of the part used as a double-sided adhesive film from raw fabric. It is a figure for
`demonstrating each manufacturing processof the transparent surface material with an adhesion layer shownin
`FIG. 1, and is sectional drawing which shows the state which removed the 2nd separator of the part used as a
`double-sided adhesive film from a raw fabric. It is a figure for demonstrating each manufacturing process of the
`transparent surface material with an adhesion layer shownin FIG. 1, and is a perspective view which shows the
`processofsticking a transparent surface material on the adhesion layer on a Ist separator. It is a figure for
`demonstrating each manufacturing processof the transparent surface material with an adhesion layer shown in
`FIG. 1, and is sectional drawing which shows the state which stuck the transparent surface material on the
`adhesion layer on a Ist separator.
`
`[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the
`drawings. In the following description, in order to make each componenteasyto see, the scale of dimensions
`may be shown differently depending on the componentin the drawings.
`
`[0013] First, an outline of a method for producing a transparent surface material with a pressure-sensitive
`adhesive layer using a double-sided pressure-sensitive adhesive film will be described. First, a long strip-shaped
`double-sided adhesive comprising an adhesivelayer, a first separator peelably attached to one surface of the
`adhesive layer, and a second separator peelably attached to the other surface of the adhesive layer Prepare a film
`source. It is necessary to cut out the double-sided adhesive film corresponding to the size of the transparent
`surface material from the raw fabric of the double-sided adhesive film by punchingorthe like. A transparent
`surface material with an adhesive layer is manufactured by peeling off one separator of the cut-out double-sided
`adhesive film and sticking to a transparent surface material.
`
`[0014] The pressure-sensitive adhesive layer-carrying transparent surface material is for peeling off the
`separator andsticking it to the object to be bonded, and therefore the separator having a larger area than the
`pressure-sensitive adhesive layer is easier to peel off. Therefore, after the said punching process,the operation|
`work which affixes the separator on oneside to a bigger thing was needed, and the process was complicated.
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`[0015] Moreover, in the punching process using the above-mentioned punching blade,after the adhesive layer is
`cut, the cut surface of the adhesive layer may be attached between the portion to be the double-sided adhesive
`film and the margin portion, There is a problem that the possibility of failure is high. For example, when there is
`a possibility that display unevenness may occur in the liquid crystal panel as in a liquid crystal panel of IPS
`mode, adhesion with a low elastic modulus (high flexibility) in the bonding step with the transparent surface
`material via the adhesive layer Layers may be used.In this case, reattachment on the cut surface is particularly
`likely to occur in the adhesive layer having a low elastic modulus.
`
`[0016] Moreover,it is also possible to manufacture the transparent surface material with an adhesion layer by a
`continuous process as follows. First, a long strip-shaped double-sided adhesive comprising an adhesive layer, a
`first separator peelably attached to one surface of the adhesive layer, and a second separator peelably attached to
`the other surface of the adhesive layer The raw material of this double-sided adhesive film is subjected to a
`punching process using a punching blade while the raw material of the film is conveyed. At this time,the first
`separator is formed by punching a punching blade from the second separator side without cutting the first
`separator and by a depth sufficient to cut the second separator and the adhesive layer. The second separator and
`adhesive layer on top are cut into a size (shape) corresponding to the double-sided adhesive film. In addition, in
`order to facilitate the punching process onthe raw fabric, a long strip-shaped raw fabric may becut into a
`predeterminedsize in advance as a step before the punching process.
`
`[0017] Moreover, since this punching processis continuously performed with respect to the raw fabric of the
`double-sided adhesive film conveyed, the part used as the said double-sided adhesive film is formed along with
`the conveyance direction on a Ist separator. become.
`
`[0018] Next, leaving the part to be the double-sided adhesive film from the raw fabric of the double-sided
`adhesive film, the second separator and the adhesive layer in the other margin part and the second onthe part to
`be the double-sided adhesive film Peel away from the separator.
`
`[0019] Next, a transparent surface material is stuck on the adhesive layer in the part used as the said double-
`sided adhesive film. The transparent surface material is sequentially attached to the portion to be the double-
`sided pressure-sensitive adhesive film aligned in the transport direction described above. Thereafter, the first
`separator is cut at the margin, that is, between the portions to be the double-sided adhesive film. Thereby, the
`transparent layer with the adhesive layer can be produced by a continuous process or a semi-continuousprocess.
`
`[0020] When manufacturing the above-mentioned transparent layer with adhesive layer continuously, leaving
`only the adhesive layer part and removing the adhesive layer and the second separator in the margin, the double-
`sided adhesive film and the transparent layer are When bonding together,the level | step difference between an
`adhesive layer part and a margin part is large, and the problem which can not be pasted well mayarise.
`Therefore, there is a need for a morereliable and efficient method of manufacturing a transparent surface
`material with an adhesivelayer.
`
`[0021] (Adhesive Layer-Containing Transparent Surface Material) First, an adhesive layer-containing
`transparent surface material 1 shown in FIG. 1, for example, will be described as an embodimentofthe present
`invention. In addition, FIG. 1 is sectional drawing which shows schematic structure of the transparent surface
`material 1 with an adhesionlayer.
`
`[0022] The transparent surface material 1 with the adhesive layer is formed by the transparent surface material 5
`bonded via the adhesive layer 2 to the surface of the display panel (bonded material) 101 includedin the display
`device 100 described later. Although it can be used for the use etc. which protect the surface of the object 101, it
`is not restricted to this use.
`
`[0023] Specifically, as shown in FIG. 1, the adhesive layer-attached transparent surface material 1 is adhered to
`the adhesive layer 2 and one surface 2 a of the adhesive layer 2 so as to be peelable, and the metal layer 3 is
`provided. Thefirst separator 4, the transparent surface material 5 attached to the other surface 2 b of the
`adhesive layer 2, the second separator 7 attached releasably to the other surface of the adhesive layer 2, and the
`adhesive layer 2 are transparent A groove portion 9 is provided to divide between a bondedportion (bonded
`region) of the face material 5 and a bonded portion (non-bondedregion) of the second separator 7.
`
`[0024] (Adhesive Layer) The adhesive layer 2 is formed by curing a liquid pressure-sensitive adhesive or a
`precursor material of the pressure-sensitive adhesive, and is made of a transparent resin composition having
`adhesiveness. Specifically, as the pressure-sensitive adhesive, a photocurable resin composition or a
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`thermosetting resin composition can be used. Among them, it is preferable to use a photocurable resin
`composition containing a curable compoundand a polymerization initiator from the viewpoint of being curable
`at low temperature and having a high curingrate.
`
`[0025] The curable compoundcontained in the pressure-sensitive adhesive has a curable group and has a
`numberaverage molecular weight of 1000 to 100000, from the viewpoint of easy adjustmentof the viscosity,
`and one or more of oligomer (A) having a number average molecular weight of 1000 to 100000, and a curable
`group. And containing at least one monomer(B) having a molecular weight of 125 to 600, and the proportion of
`the monomer(B) is the total (100% by mass) of the oligomer (A) and the monomer(B) It is preferable to use
`what is 20 mass%-80 mass% among them.
`
`[0026] Examples of the curable group of the oligomer (A) include addition polymerizable unsaturated groups
`(for example, acryloyloxy group, methacryloyloxy group and the like), combinations of unsaturated groups and
`thiol groups, and the like. Among them,as the curable group of the oligomer(A), it is preferable to use a group
`selected from an acryloyloxy group and a methacryloyloxy group from the viewpoint of a high curing speed and
`a highly transparent adhesive layer.
`
`[0027] As an oligomer (A), what has an average of 1.8-4 curable groups per molecule from the point of
`hardenability and mechanical characteristics is preferable. As an oligomer (A), the urethane oligomer which has
`a urethane bond, the poly (meth) acrylate of polyoxyalkylene polyol, the poly (meth) acrylate of polyester
`polyol, etc. are mentioned. In addition, as the oligomer(A), it is preferable to use a urethane oligomer (A1) from
`the viewpoint that the mechanical properties and the adhesion after curing can be widely adjusted by the
`molecular design of the urethane chain and the like. Moreover, an oligomer (A) may be used individually by 1
`type, and may use 2 or more types together.
`
`[0028] Examples of the curable group of the monomer(B) include addition polymerizable unsaturated groups
`such as acryloyloxy group and methacryloyloxy group, or a combination of unsaturated group andthiol group.
`Among them, as the curable group of the monomer(B), it is preferable to use a group selected from an
`acryloyloxy group and a methacryloyloxy group from the viewpoint of a high curing rate and a highly
`transparent adhesive layer.
`
`[0029] The monomer(B) preferably contains a monomer (B3) having a hydroxyl group from the viewpoint of
`adhesion and solubility of various additives. As a monomer (B3) which has a hydroxy! group, it is preferable to
`use the hydroxy acrylate which has a hydroxyl group having a hydroxy] numberof 1 to 2 and a carbon number
`of 3 to 8 or a hydroxy methacrylate. Specifically, for example, 2-hydroxypropyl acrylate, 2-hydroxybutyl
`acrylate, 4-hydroxybuty] acrylate, 6-hydroxyhexyl] acrylate, 2-hydroxypropyl methacrylate, 2-hydroxybuty]
`methacrylate, 4-hydroxybutyl methacrylate, 6 -Hydroxyhexy] methacrylate and the like. Among these, 4-
`hydroxybutyl acrylate and 2-hydroxybutyl methacrylate are particularly preferably used. Moreover, a monomer
`(B) may be used individually by 1 type, and may use 2 or more types together.
`
`[0030] The adhesive may contain the following non-curable oligomers (D). Specifically, this non-curable
`oligomer (D) is an oligomer having a hydroxyl group which doesnot cure with the oligomer (A) and the
`monomer(B) at the time of curing, and its number average molecular weight (Mn) is 400 to 8000. The number
`of hydroxyl groups per molecule is 0.8 to 3.
`
`[0031] When the non-curable oligomer(D)is contained, the non-curable oligomer (C) after curing by the
`interaction between the hydroxyl group derived from the cured product containing the monomer (B3) and the
`hydroxy] group of the non-curable oligomer(D)It is easy to obtain the effect of stabilizing D). Also, it is
`speculated that the interaction between the monomer(B3) and the non-curable oligomer (D) involves hydrogen
`bonding.
`
`[0032] Examples of the non-curable oligomer (D) containing a hydroxyl group include high molecular weight
`polyols and the like. Among them,as the non-curable oligomer (D), it is preferable to use polyoxyalkylene
`polyol, polyester polyol and polycarbonate polyol. The non-curable oligomer (D) improves the affinity of the
`pressure-sensitive adhesive before curing by including the polyol used for the synthesis of the oligomer(A).
`Moreover, a non-curable oligomer (D) may be used individually by 1 type, and may use 2 or more types
`together.
`
`[0033] Examples of the polymerization initiator include photopolymerization initiators of acetophenone type,
`ketal type, benzoin or benzoin ether type, phosphine oxide type, benzophenonetype, thioxanthone type, quinone
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`type and the like. By using two or more types of polymerization initiators having different absorption
`wavelength ranges in combination, the curing time can be further accelerated or the surface curability of the
`adhesive layer 2 can be enhanced.
`
`[0034] The viscosity of the adhesive or the precursor material of the adhesive is preferably 1 Pa - s to 100 Pa-s,
`more preferably 2 Pa - s to 50 Pa- s, and 3 Pa- s to 30 Pa- s Is more preferred. If the viscosity of the pressure -
`sensitive adhesive or the precursor material of the pressure-sensitive adhesive is 1 Pa - s or more, the pressure-
`sensitive adhesive or the pressure-sensitive adhesive precursor can sufficiently maintain the height of the layer.
`On the other hand, if the viscosity of the pressure-sensitive adhesive or the precursor material of the pressure-
`sensitive adhesive is 100 Pa - s orless, the pressure-sensitive adhesive or the precursor material of the pressure-
`sensitive adhesive can be easily applied. In the present embodiment, the viscosity of the pressure-sensitive
`adhesive or the precursor material of the pressure-sensitive adhesive at 25 ° C. was measured using an E-type
`viscometer.
`
`[0035] The shear modulusofelasticity of the adhesive layer 2 at 25 ° C. is preferably 10 3 Pa to 10 6 Pa, more
`preferably 10 3 Pa to 10 5 Pa, and 10 3 Pa to 10 4 Pa Morepreferable.
`
`[0036] If the shear modulus of the adhesive layer 2 is 10 3 Pa or more, the shape of the adhesive layer 2 can be
`maintained. In addition, even when the thickness of the adhesive layer 2 is relatively thick, the thickness of the
`adhesive layer 2 can be maintained uniform. Furthermore, when the shear modulusof the adhesive layer 2 is 10
`3 Pa or more, deformation of the adhesive layer 2 can be easily suppressed when the first separator 4 is peeled
`off. On the other hand, if the shear modulusof the adhesive layer 2 is 10 6 Pa or less, good adhesion can be
`exhibited at the interface between the adhesive layer 2 and the display panel. Moreover, about the adhesion layer
`2 by which the transparent surface material 5 was stuck, even if a shear elasticity modulus is made smallin the
`range of 10 3 Pa-10 6 Pa, for example, by supporting by the transparent surface material 5, that The shape can
`be sufficiently maintained.
`
`[0037] In the present embodiment, the shear modulus of the adhesive layer 2 at 25 ° C. was measured using the
`following method. By using a rheometer (modular rheometer Physica MCR-301, manufactured by Anton Paar),
`the gap between the measuring spindle and the transparent plate is made equal to the average thickness of the
`adhesive layer 2 and uncured in the gap Place the pressure sensitive adhesive. Furthermore, while applying heat
`or light required for curing to the uncured pressure-sensitive adhesive, the shear modulusin the curing processis
`measured, and the measured value under predetermined curing conditions is taken as the shear modulusof the
`adhesive layer2.
`
`[0038] The average thickness of the adhesive layer 2 is preferably 0.03 mm to 2 mm, more preferably 0.1 mm to
`0.8 mm,andstill more preferably 0.3 mm to 0.5 mm.If the average thickness of the adhesive layer 2 is 0.03 mm
`or more, the adhesive layer 2 can effectively buffer an impact or the like due to an external force from the
`transparent surface material 5 side, thereby protecting the display panel. In addition, the average thickness of the
`adhesive layer 2 largely changes evenif foreign matter not exceeding the thickness of the adhesive layer 2 is
`mixed between the transparent surface material 1 with the adhesive layer and the display panelat the time of
`manufacturing the display device. There is little impact on transparency performance. Onthe other hand,if the
`average thickness of the adhesive layer 2 is 2 mm orless, the entire thickness of the display device is not
`unnecessarily increased. In addition, as a method of adjusting the thickness of the adhesion layer 2, the method
`of adjusting the quantity of an adhesive at the time of manufacture is mentioned.
`
`[0039] Further, in the present embodiment, since the non-adhesion area is provided around the adhesion area of
`the adhesive layer 2, the adhesion area is protected from the intrusion of foreign matter into the adhesion area,
`and the impact and stress during transportation.It is desirable because it can be done.
`
`[0040] (Metal Layer) The metal layer 3 is for preventing the first separator 4 from being cut when the adhesive
`layer 2 is cut by the irradiation of a laser beam in the manufacturing process of the present embodiment
`describedlater. . It is preferable that the metal layer 3 be disposedin the layer ofthe first separator 4 in
`consideration of adhesion with the adhesive layer 2. However, the metal layer 3 may be disposed on the surface
`of the first separator 4 on the adhesive layer 2 side or the surface on the oppositeside.
`
`[0041] The metal layer 3 preferably has a function as a reflection layer that reflects laser light and a function as
`a heat sink layer that dissipates heat whenthe laser light is irradiated. In addition, the metal layer 3 has a
`function as a protective layer that protects the adhesive layer 2 together with the first separator 4 by being
`disposedin the layerof the first separator 4. As the metal layer 3 having such a function, an Al film or an Al
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`alloy film can be suitably used. Also, other metal films may be used. The metal layer 3 is formed, for example,
`after adhering a metal foil to one surface of the resin layer formingthe first separator 4, or after forming a metal
`film using a vacuum deposition method or sputtering method, etc. By laminating another resin layer forming the
`first separator 4, it can be disposed in the layer ofthe first separator 4.
`
`[0042] (First Separator) The first separator 4 has a function as a protective film for protecting one surface of the
`adhesive layer 2 (the surface opposite to the side on which the transparent surface material 5 is adhered) 2a, and
`the adhesive layer 2 It has a function as a release film pasted so as to be peelable on one side 2a. In addition, as a
`forming material of the first separator 4, it is preferable to use a resin material having a small elongation in the
`process of forming the adhesive layer 2, for example, polyethylene terephthalate (PET), polybutylene
`terephthalate (PBT), polyethylene naphthalate ( Examples thereof include polyester resins such as PEN),
`polyamideresins such as nylon-6 and nylon-66, and olefin resins such as biaxially stretched polypropylene.
`When “elongation” is compared for the forming material of the first separator 4, the value of elongation
`obtained by the method defined in ASTM D638 is used.
`
`[0043] The combined thickness of the first separator 4 and the metal layer 3 (hereinafter referred to as protective
`layer thickness) is different depending on the material, but a relatively flexible resin material such as the
`biaxially stretched polypropylene described aboveis used. In the case, the protective layer thickness is
`preferably in the range of 40 um to 120 xm. Whenthe protective layer thickness is 40 um or more, deformation
`of the first separator 4 and the metal layer 3 can be suppressed when peeling the first separator 4 and the metal
`layer 3 from the adhesive layer 2. On the other hand, whenthe protective layer thickness is 120 um orless, the
`first separator 4 and the metal layer 3 are easily bent at the time of peeling and are easily peeled. In addition,as
`shown in FIG.1, it is preferable that the separator 4 have a larger area than the area bondedto the adhesive layer
`2 because it is easy to peel off.
`
`[0044] Moreover, when using resin materials with comparatively small expansion| extension, such as PET
`mentioned above,it is preferable to make protective layer thickness into the range of 20 micrometers-100
`micrometers. Whenthe protective layer thickness is 20 um or more, excessive deformationofthe first separator
`4 and the metal layer 3 can be suppressed when peeling the first separator 4 and the metal layer 3 from the
`adhesive layer 2. On the other hand, whenthe protective layer thickness is 100 jm orless, the first separator 4
`and the metal layer 3 are easily bent at the time of peeling, and it becomeseasy to peel.
`
`[0045] It is preferable that a release agent is applied to the surface ofthe first separator 4 to be attached to the
`pressure-sensitive adhesive layer 2. Thereby, the adhesion to the adhesive layer 2 can be reduced, and the
`adhesive layer 2 can be easily peeled off. The release agent is not particularly limited, and those conventionally
`used as a release agentfor the first separator 4 can be used. In addition, instead of applying the release agent, a
`release film in which the release agent is applied in advanceto a base film such as a polyester film is applied to
`the side of the first separator 4 to be attached to the adhesive layer 2. The release agent may be bondedso as to
`be in contact with the adhesive layer 2. The dry lamination method etc. can be used for bonding of a release
`film. When the dry lamination methodis used, the base film of the release film and the first separator 4 are
`adhered via another bonding layer. Further, instead of the release film, a resin film having a small adhesion to an
`adhesive layer such as polyolefin or fluorine resin may be used by being bondedto the first separator 4. As
`polyolefin, although polyethylene, a polypropylene, etc. are mentioned, it is preferable to use the biaxially
`stretched polypropylene from a viewpoint of mechanicalstrength.
`
`[0046] Thefirst separator 4 is a resin film (referred to asa first film) to which the above-described release agent
`is applied, and a resin film (referred to as a second film) in which the elongation as a base material is desirably
`small. It may be configured to be laminated via the layer 3. In the case of this configuration,it is preferable that
`the surface of the first film to which the release agent is applied be the adhesive layer 2 side and the second film
`be the opposite side to the adhesive layer 2. Thefirst film and the second film may use the same material or
`different materials.
`
`[0047] In addition, a gas barrier layer (not shown) may be provided onthefirst film or the secondfilm. In the
`case of this configuration, the gap at the time of bonding with the display panel can be suppressed. Asthe gas
`barrier layer, a material in which an inorganic compound or an inorganic compoundis dispersed in a resin can
`be used. In addition, a film having a gas barrier effect may be sandwiched betweenthefirst film and the second
`film. When the metal layer 3 has gas barrier properties, the gas barrier layer can be omitted.
`
`[0048] (Second Separator) The second separator 7 has a function as a protective film for protecting the other
`surface 2 b of the adhesive layer 2 located outside the groove 9. The adhesive layer 2 located outside the groove
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`9 prevents the other surface 2 b from being exposed by the second separator 7. As a forming material of the
`second separator 7, the same oneasthe first separator 4 can be used.
`
`[0049] (Grooves) The grooves 9 are formed by cutting the adhesive layer 2 by laser beam irradiation in the
`manufacturing process of the embodiment described later. The adhesive layer 2 prevents the cut surface between
`the adhered portion of the transparent surface material 5 and the adhered portion of the second separator 7 from
`adhering by the groove portion 9. The width W of the groove 9 is preferably at least one tenth of the thickness T
`of the adhesive layer 2 (W 2 T/ 10). Thereby,it is possible to prevent the cut surface from adheringafter the
`adhesive layer 2 is cut.
`
`[0050] (Transparent Surface Material) The transparent surface material 5 has a function as a protective plate for
`protecting the display panel. As a forming material of the transparent surface material 5, it is possible to use a
`parallel flat plate, a plate-like glass having a curved surface or a transparent resin, or a laminate of glass and a
`transparent resin. Among them,it is preferable to use glass in terms of transparency,light resistance, low
`birefringence, plane accuracy, surface scratch resistance (abrasion resistance), mechanical strength andthe like.
`
`[0051] Examples of the glass include glass materials such as soda lime glass. Among them,it is more preferable
`to use high-permeability glass (white plate glass) having lower iron content and less bluish color. Moreover, as
`glass, in order to improve safety, tempered glass may be used, and glass to which chemical strengthening has
`been applied maybe used.
`
`[0052] Examples of the transparent resin include highly transparent resin materials such as polycarbonate (PC)
`and polymethyl methacrylate (PMMA). Moreover,as long as it has the required transparency,a resin plate in
`which two or more types of resin materials are laminated may be used, and a resin plate in which a resin
`composition in which two or more types of resin materials or fillers are mixed is a forming material May be
`used.
`
`[0053] The transparent face material 5 may be subjected to surface treatment for improving the interfacial
`adhesion with the adhesive layer 2. As a method of surface treatment, there is mentioned a methodoftreating