JP2009275091A - Adhesive composition for optical functional member-integrated display device, and optical functional member-integrated display device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device that exhibits excellent adhesion between an optical functional member and an adherend of a display part, hardly suffers from peeling, is excellently durable and exhibits good visual recognizability of a display part of a display and the like. <P>SOLUTION: The adhesive composition for optical functional member-integrated display device for bonding an optical functional member to a display part of an optical functional member-integrated display device composed of the optical functional member integrated with the display part comprises as essential ingredients a raw resin material, a photopolymerization initiator and an organic peroxide, where at least two monomers having different reactivity are incorporated with the raw resin material. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a light-transmitting full-surface plate for impact resistance, used as a light-transmitting member, an antireflection film, an antireflection glass, an antistatic glass, an antistatic film, an electromagnetic shielding material, and a near infrared absorbing film. The present invention relates to an adhesive composition used for bonding an optical functional member such as a color filter and a display unit such as electronic paper or LCD (liquid crystal), an optical functional member integrated display device, and a method for manufacturing the same.

  Optical with a structure in which an optical function member such as an anti-reflection film, anti-reflection glass, anti-static glass, anti-static film, electromagnetic wave shielding material, near-infrared absorbing film, and color filter is integrated with a display unit such as a CRT or LCD. In the process of manufacturing a functional member-integrated display device, lamination with an adhesive is often performed in order to fill a gap between the optical functional member and the display unit. In this case, in order to improve impact resistance and followability, it is desirable to laminate an adhesive layer as thick as possible. In conventional solvent dilution type adhesives, those having a solid content concentration as low as about 30% are used, and it is necessary to sufficiently dilute the solvent. In order to volatilize the solvent sufficiently, an adhesive of 50 μm or more is required. It was difficult to form a film.

  Therefore, a solvent-free film-forming system using an acrylic syrup in which an acrylic polymer is dissolved in a low molecular weight acrylic monomer as a raw material (resin component) has been found, and it has become possible to produce an adhesive having a thickness of about 500 μm (this application) (See Japanese Patent Application No. 2007-148783 filed earlier by humans).

  However, in the prior art, the pressure-sensitive adhesive is completely cross-linked at the time of film formation, so that the adhesiveness with the adherend is lowered, and severe peeling has occurred in endurance tests such as heat shock.

  Therefore, the applicant of the present application has applied for Japanese Patent Application No. 2007-278455 as the above-mentioned anti-peeling measure. In the invention according to this application, the adhesive composition containing a mixture of an acrylic polymer and a monomer is bonded at the time of thermal crosslinking by a stepwise crosslinking reaction between UV crosslinking and thermal crosslinking after lamination. The purpose is to develop a primary bond between the agent and the adherend interface. However, most of the acrylic groups reacted at the stage of UV crosslinking, and it was difficult to sufficiently perform the thermal crosslinking reaction after lamination.

In addition, the following patent documents 1-3 are mentioned as a prior art relevant to the invention which concerns on this application.
JP 2001-19925 A JP 2001-26758 A Japanese Patent Laid-Open No. 2002-140014

  The present invention has been made in view of the above circumstances, and when the stepwise crosslinking reaction between UV crosslinking and thermal crosslinking after lamination proceeds, the latter thermal crosslinking reaction is sufficiently performed so that the adhesive and Adhesive composition for an optical functional member-integrated display device that exhibits primary bonding with an adherend interface, improves adhesion, and has excellent durability without peeling, and the adhesive composition It is an object of the present invention to provide an optical functional member integrated display device using an object and a manufacturing method thereof.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention sufficiently perform the latter thermal crosslinking reaction when the stepwise crosslinking reaction between UV crosslinking and thermal crosslinking after lamination proceeds. Reduces the acceleration of the reaction of the former UV crosslinking, and as a means for this, in the conventional adhesive composition in which most of the acrylic groups react during UV crosslinking, a monomer having a methacrylic group that is sufficiently less reactive than the acrylic group is used. It is focused on mixing, and by this, thermal crosslinking can be performed sufficiently, the adhesiveness between the adhesive and the adherend is improved, and it is found that there is almost no peeling and excellent durability. The present invention has been made.

Accordingly, the present invention provides the following adhesive composition for an optical functional member integrated display device, an optical functional member integrated display device, and a method for producing the same.
[1] Adhering the optical functional member and the display unit of the optical functional member integrated display device in which the optical functional member and the display unit are integrated, and essential raw material resin material, photopolymerization initiator and organic peroxide An adhesive composition for a display device integrated with an optical function member, wherein the raw material resin material is mixed with at least two types of monomers having different reactivity.
[2] The adhesive composition for an optical functional member-integrated display device according to [1], wherein the two types of monomers are an acrylate monomer and a polymer having a lower reactivity than the acrylate monomer.
[3] The adhesive composition for an optical function member-integrated display device according to [1] or [2], wherein the two types of monomers are an acrylate monomer and a methacrylate monomer.
[4] The adhesive composition for an optical function member-integrated display device according to [1], [2] or [3], wherein the raw material resin material is a material obtained by dissolving a raw material polymer in a low molecular weight raw material monomer.
[5] The adhesive composition for an optical function member-integrated display device according to [4], wherein the raw material polymer is contained in an amount of 5 to 80% by mass based on the raw material resin material.
[6] The optical function member integrated type according to any one of [1] to [5], wherein a total of 0.1 to 30 parts by mass of the at least two types of monomers is blended with respect to 100 parts by mass of the raw material resin material. Adhesive composition for display device.
[7] An optical function member-integrated display device in which an optical function member and a display unit are laminated via the adhesive according to any one of [1] to [6].
[8] In the method for producing an optical function member integrated display device in which the optical function member and the display unit are integrated, the adhesive composition for bonding the optical function member and the display unit as claimed in any one of claims 1 to 6. Using the adhesive composition according to any one of the above, the adhesive composition is photocured in advance to prepare a partially crosslinked adhesive composition, and then the optical composition is passed through the adhesive composition. A method for producing a display device integrated with an optical function member, wherein the functional member and the display unit are bonded together, and then the adhesive composition is thermally cured by heat treatment.

  According to the adhesive composition for an optical functional member-integrated display device of the present invention, the optical functional member and the display portion are excellent in adhesion to the adherend, have almost no peeling, and have excellent durability. Thus, a display device with good visibility of the display unit and the like can be provided.

  In the adhesive composition for an optical functional member-integrated display device of the present invention, a resin material having a raw material polymer is blended as an essential component. The form of the raw material polymer is a monomer of the polymer (raw material monomer). It is preferable to use it diluted. The reason is that it is possible to form a film thickness of 100 μm or more, which is difficult in a solvent system, by using the adhesive composition by a wet lamination method and a UV irradiation film forming method. .

  The mixing ratio (mass ratio) of the raw material polymer and the raw material monomer in the mixture is preferably 5/95 to 80/20, more preferably 10/90 to 70/30. When the amount of the raw material polymer is too large, the viscosity becomes too high and not only the workability is deteriorated but also the followability is deteriorated, and there is a possibility that voids and bubbles are generated during the lamination process. On the other hand, when the amount of the raw material polymer is too small, the viscosity becomes too low, and there is a possibility that the oozing occurs and the workability is lowered.

  In addition, it is preferable that the number average molecular weight of the raw material polymer in the said raw material resin material is 20000-300000 normally, More preferably, it is 50000-200000. Moreover, it is preferable that the viscosity of the said mixture is 0.2-30 Pa.s, More preferably, it is 0.5-20 Pa.s.

  Here, the raw material polymer is not particularly limited. For example, acrylic resin, polyvinyl acetate, vinyl acetate / (meth) acrylate copolymer, ethylene / vinyl acetate copolymer, polystyrene and its copolymer, Polyvinyl chloride and its copolymer, butadiene / acrylonitrile copolymer, acrylonitrile / butadiene / styrene copolymer, methacrylate / acrylonitrile / butadiene / styrene copolymer, 2-chlorobutadiene-1,3-polymer, chlorinated rubber Styrene / butadiene / styrene copolymer, styrene / isoprene / styrene block copolymer, epoxy resin, polyamide, polyester, polyurethane, cellulose ester, cellulose ether, polycarbonate, polyvinyl acetal, etc. It can be. In particular, from the viewpoint of solubility in an acrylic monomer, the raw material polymer preferably employs an acrylate-based and / or methacrylate-based polymer. Moreover, when using an acrylate type and / or a methacrylate type polymer, it is preferable to contain the repeating unit of methyl methacrylate at least 50 mass% (especially 60-90 mass%).

  When the raw material polymer is an acrylate-based and / or methacrylate-based polymer, it is preferable to use a resin material diluted with an acrylic monomer. Specific examples include a polymer / monomer mixture obtained by diluting an acrylic polymer with a monomer (trade name “Syrup”, manufactured by Soken Chemical Co., Ltd.). By using such a mixture, it is possible to make the solution solvent-free.

  Here, the present invention is characterized in that the raw material resin material is mixed with at least two types of monomers having different reactivities. The at least two types of monomers having different reactivities mean monomers having a functional group that reacts by radical polymerization.

  Of the two types of monomers, one is an acrylate monomer and the other is preferably a polymer having a lower reactivity than the acrylate monomer. Specifically, the following methacrylate monomer and acrylate are used. It is preferable to employ a combination with a monomer.

Methacrylate monomers As methacrylate monomers, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, isodecyl methacrylate, n-lauryl methacrylate, alkyl group having 12 to 12 carbon atoms 15 alkyl methacrylate, n-stearyl methacrylate, butoxydiethylene glycol methacrylate, methoxytriethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, benzyl methacrylate, phenoxyethyl methacrylate, isobornyl methacrylate, 2-hydroxy ester Methacrylate, 2-hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, quaternized product of dimethylaminoethyl methacrylate, methacrylic acid, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, 2-methacryloyloxyethyl-2-hydroxypropyl phthalate, glycidyl methacrylate, 2-methacryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, PEG # 200 Dimethacrylate, PEG # 400 Dimethacrylate PEG # 600 Dimethac 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, glycerin dimethacrylate, 2- It is selected from the group consisting of hydroxy-3-acryloyloxypropyl methacrylate, EO-additive dimethacrylate of bisphenol A, trimethylolpropane trimethacrylate, trifluoroethyl methacrylate, and perfluorooctylethyl methacrylate. Specifically, commercial products such as “light ester” and “light acrylate” in the product series manufactured by Kyoeisha Chemical Co., Ltd. can be used as these compounds.

Acrylate monomers As acrylate monomers, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, isoamyl acrylate, lauryl acrylate, isomyristyl acrylate, stearyl acrylate, butoxyethyl acrylate, ethoxy diethylene glycol acrylate, methoxy triethylene glycol acrylate, 2-ethylhexyl-diglycol acrylate, methoxy-polyethylene glycol acrylate, methoxydipropylene glycol acrylate, phenoxyethyl acrylate, phenoxy-polyethylene glycol acrylate, nonylphenol EO adduct acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, 2-hydroxy Ethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxy Ethylphthalic acid, 2-acryloyloxyethyl-2-hydroxyethyl-phthalic acid, neopentyl-glycol acrylic acid benzoate, 2-acryloyloxyethyl acid phosphate, triethylene glycol diacrylate, PEG200 # diacrylate, PEG400 # Diacrylate, PEG600 # diacrylate, polytetramethylene glycol diacrylate, neopentyl glycol diacrylate, 3-methyl-1,5-pentane All diacrylate, 1,6-hexanediol diacrylate, 2-butyl-2-ethyl-1,3-propanediol diacrylate, 1,9-nonanediol diacrylate, 2-methyl-1,8-octanediol diacrylate Mixture of acrylate and 1,9-nonanediol acrylate, dimethylol tricyclodecane diacrylate, EO adduct diacrylate of bisphenol A, PO adduct diacrylate of bisphenol A, trimethylolpropane acrylate benzoate, hydroxybiba Neopentyl glycol diacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, trimethylolpropane triacrylate, EO-modified silmethylolpropane triacrylate, pentaerythrito Selected from the group consisting of triethyltriacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, and perfluorooctylethyl acrylate. Specifically, commercial products such as “light ester” and “light acrylate” in the product series manufactured by Kyoeisha Chemical Co., Ltd. can be used as these compounds.

  In the present invention, the acrylate monomer and the methacrylate monomer are respectively selected from the above groups and can be used in combination of not only one type but also two or more types from each group.

  The total amount of the at least two types of monomers is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the raw material resin material, and the upper limit is 10 parts by mass or less. This is preferable from the viewpoint of effectively exhibiting the effects of the invention.

  Moreover, a photopolymerization initiator is blended as an essential component in the adhesive composition. A known photopolymerization initiator can be used as the type. Specific examples of the photopolymerization initiator include benzoin series such as acetophenone series and benzyldimethyl ketal, thioxanthone series such as benzophenone series, isopropylthioxanthone and 2-4-diethylthioxanthone, and other special ones such as methylphenylglycol. Oxylate can be used. Particularly preferably, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1, Examples include benzophenone. These photopolymerization initiators are optionally selected from one or more of known benzoic acid-based accelerators such as 4-dimethylaminobenzoic acid or tertiary amine-based conventional photopolymerization accelerators. It can be used by mixing at a ratio.

  About the compounding quantity of the said photoinitiator, in the case of this invention, it shall be 0.01-1.0 mass part with respect to 100 mass parts of said raw material polymers, especially 0.05-0.3 mass part. Is preferred.

  Examples of the acetophenone-based polymerization initiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, 4-t-butyl-trichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenyl. Propan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1, and the like As the benzophenone polymerization initiator, benzophenone, Nzoiru benzoate, methyl benzoyl benzoate, 4-phenyl benzophenone, hydroxybenzophenone, 4-Benzzoiru 4'-methyl diphenyl sulfide, 3,3'-dimethyl-4-methoxybenzophenone and the like can be used.

  Examples of the acetophenone polymerization initiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl)- 2-morpholinopropane-1 is preferred. As the benzophenone polymerization initiator, benzophenone, benzoylbenzoic acid, and methyl benzoylbenzoate are preferable. Tertiary amine photopolymerization accelerators include triethanolamine, methyldiethanolamine, triisopropanolamine, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, ethyl 2-dimethylaminobenzoate. , Ethyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate (n-butoxy), isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, and the like. Particularly preferably, as the photopolymerization accelerator, ethyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate (n-butoxy), isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, etc. Is mentioned.

  An organic peroxide is blended as an essential component in the adhesive composition together with the photopolymerization initiator. Examples of the organic peroxide include 2,5-dimethylhexane-2,5-dihydroxyperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, di-t. -Butyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide, α, α'-bis (t-butylperoxyisopropyl) ) Benzene; n-butyl-4,4-bis- (t-butylperoxy) valerate, 2,2-bis (t-butylperoxy) butane, 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, t-butylperoxybenzoate, benzoyl peroxide, t-butyl Tilperoxyacetate, methyl ethyl ketone peroxide, t-butyl hydroperoxide, p-menthane hydroperoxide, hydroxyheptyl peroxide, chlorohexanone peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, cumyl peroxide Octoate, succinic acid peroxide, acetyl peroxide, t-butyl peroxide (2-ethylhexanoate), m-toluoyl peroxide, benzoyl peroxide, t-butyl peroxyisobutyrate, 2,4 -Dichlorobenzoyl peroxide etc. are mentioned, It can mix | blend suitably according to the required curing temperature, time, physical properties, etc.

  As the organic peroxide, one of these can be used alone or in admixture of two or more, and the addition amount is usually 0.1 to 10 parts by mass with respect to 100 parts by mass of the raw material polymer. In particular, 0.2 to 2.0 parts by mass is recommended. If the blending amount is small, curing sufficient for durability cannot be obtained, and if the blending amount is large, unreacted products and by-products after curing increase, which may deteriorate the performance.

  In addition to the raw material resin material, photopolymerization initiator, and organic peroxide, the adhesive composition may contain known additives. For example, a silane coupling agent can be added to promote adhesion. Specific examples of the silane coupling agent include vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, and γ-glycidoxypropyltrimethoxysilane. , Γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-chloropropylmethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltri Examples include ethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, and the like. One of these can be used alone, or two or more can be used in combination. The addition amount of these silane coupling agents is 0.01-5 mass parts normally with respect to 100 mass parts of said raw material polymers.

  Moreover, an epoxy group-containing compound can also be added for the purpose of improving adhesiveness. Examples of the epoxy group-containing compound include triglycidyl tris (2-hydroxyethyl) isocyanurate, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, acrylic glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, Examples thereof include phenol glycidyl ether, pt-butylphenyl glycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, glycidyl methacrylate, butyl glycidyl ether, and the like. be able to. The addition amount of these epoxy group-containing compounds is usually 0.1 to 20 parts by mass with respect to 100 parts by mass of the raw material polymer.

  Furthermore, as another additive, a hydrocarbon resin can be added for the purpose of improving processability such as processability and bonding. In this case, the added hydrocarbon resin may be either a natural resin type or a synthetic resin type. As the natural resin system, rosin, rosin derivatives, and terpene resins are preferably used. As the rosin, gum resin, tall oil resin, and wood resin can be used. As the rosin derivative, rosin obtained by hydrogenation, heterogeneity, polymerization, esterification, or metal chloride can be used. As the terpene resin, a terpene phenol resin can be used in addition to a terpene resin such as α-pinene and β-pinene. In addition, dammar, corbal and shellac may be used as other natural resins. On the other hand, in the synthetic resin system, petroleum resin, phenol resin, and xylene resin are preferably used. As the petroleum resin, aliphatic petroleum resin, aromatic petroleum resin, alicyclic petroleum resin, copolymer petroleum resin, hydrogenated petroleum resin, pure monomer petroleum resin, and coumarone indene resin can be used. As the phenol resin, an alkyl phenol resin or a modified phenol resin can be used. As the xylene-based resin, a xylene resin or a modified xylene resin can be used.

  Although the addition amount of the said hydrocarbon resin etc. is selected suitably, 1-200 mass parts is preferable with respect to 100 mass parts of said raw material polymers, More preferably, it is 5-150 mass parts.

  In addition, in the said adhesive composition, a ultraviolet absorber, anti-aging agent, dye, a processing aid, etc. can be suitably added as needed.

  Next, the adhesive composition is used for the purpose of bonding adherends (optical functional member and display unit) to each other by curing. In the present invention, the effects of the present invention are achieved by adopting the following manufacturing process. Can be exhibited effectively. That is, the present invention employs a production method having a two-stage curing process, a process (1) for photocuring the adhesive composition and a process (2) for further thermosetting the adhesive composition. Is preferred. This will be described below.

Process (1)
The adhesive composition contains a photopolymerization initiator as an essential component, and the adhesive composition is photocured under predetermined conditions. The predetermined condition, 1~50mW / cm ^2, desirably from 3~10mW / cm ^2, also, 100~5000mJ / cm ^2, desirably 500~2000mJ / cm ^2.

  Moreover, as an aspect of the photocuring of the adhesive composition, for example, it can be formed into a film while photocuring the adhesive composition by a film forming method such as calendar, roll, T-die extrusion, and inflation. . In this case, the thickness of the film to be formed is appropriately selected, but is preferably 10 to 3000 μm, more preferably 50 to 1000 μm, and particularly preferably 50 to 500 μm.

  Moreover, it is possible to apply | coat an adhesive composition using various lamination apparatuses by a wet laminating system etc., and to obtain an adhesive composition by photocuring. The wet laminating method is to apply an adhesive composition on a release film and bond it with another release film using a pressure roll etc. before the adhesive composition is cured or gelled, and then photocured. This is a solventless method in which the coating liquid is cured by reaction or the like to form a film. Specifically, the coating mechanism shown in FIG. 1 (A) can be used, and the release film 12 is continuously sent out from the unwinding roller 20 in the direction of the arrow in the drawing, and the adhesive composition is supplied from the liquid dam 15. While being applied to one surface of the release film 12, another release film 11 is sent out from another unwinding roller 30, and both release films 12, 11 are bonded together by a wet laminip 40. In this way, the adhesive layer 10 having a predetermined thickness obtained by photocuring the adhesive composition can be laminated between the laminated films 11 and 12, and these are wound up by the winding roller 60.

  In the present invention, as described above, the coating liquid containing the adhesive composition is applied to the release film, and another release film is bonded to the coated film, and the coating liquid is photocured in this state. The method can be suitably employed.

In the present invention, as a photo-curing irradiation source (reference numeral 70 in FIG. 1), many light emitting materials in the ultraviolet to visible region can be employed. For example, ultra high pressure, high pressure, low pressure mercury lamp, chemical lamp, xenon lamp, halogen lamp, mercury lamp, black light, carbon arc lamp, incandescent lamp, laser light and the like can be mentioned. In particular, a lighting device such as a black light can be preferably used. The irradiation intensity depends on the composition and hardness of the adhesive composition to be used, but it is usually irradiated with relatively weak light of about 1 to 10 mW / cm ² , preferably 3 to 10 mW / cm ^2. At the same time, the irradiation time is not generally determined depending on the type of lamp and the intensity of the light source, but it can be set to several tens of seconds to several tens of minutes, preferably 30 seconds to 5 minutes. If the irradiation intensity and time are exceeded from the above ranges, the curing reaction of the adhesive composition as a subsequent step cannot be performed sufficiently and effectively, and the desired effect of the present invention may not be obtained.

The adhesive composition thus obtained has a partially crosslinked structure. In the present invention, as the adhesive composition, in addition to the raw material resin material, two types of monomers having different reactivity are included, and among these, highly reactive monomers such as acrylic monomers are preferentially used for UV crosslinking. Is done. In this case, the crosslinking conversion rate of the adhesive composition is 20 to 95%, preferably 30 to 90%. It is desirable that the crosslinking conversion rate can be made as low as possible and a film can be formed. Incidentally, the crosslinking conversion is, if the area of measuring the IR spectrum from 1,600 to 1,620 / cm a (C = C) area of S _1, and 1700~1720 / cm (-CO-) was S _2, UV The S _i / S _L measurement value of the coating liquid before irradiation is defined as the conversion rate 0, the S ₁ / S ₂ measurement value when UV irradiation and heating are excessively performed is defined as the conversion rate 100%, and S ₁ / S ₂ It is estimated to be a linear function and quantified by the measured conversion rate.

  In the optical function member integrated display device of the present invention, an adhesive layer (adhesive) made of the above adhesive composition is interposed between the optical function member and the display portion, and further, the crosslinking reaction is completed by performing thermosetting. Thus, an optical functional member integrated display device in which the optical functional member and the display unit are bonded together is obtained.

  Here, the optical functional member may be a known one, for example, a light-transmissive antireflection glass, an antireflection film, an antistatic glass, an antistatic film, an electromagnetic wave shielding material, a near infrared absorbing film, A color filter or the like can be suitably used.

  On the other hand, as the display unit, a known one such as a CRT or LCD can be used.

Step (2)
Next, the process (2) of thermosetting the adhesive composition will be described. Using the above-described photocured adhesive composition, the optical functional member, which is an adherend, and the display unit are bonded and integrated. As this bonding method, for example, release films 11 and 12 (laminated body) in which the adhesive composition 10 shown in FIG. 1B is interposed can be used, but are not limited thereto. .

  Moreover, a well-known method can be employ | adopted as a method of adhere | attaching an LCD panel and an optical function member using this laminated body. Although not specifically illustrated, when the adhesive composition 10 is bonded to the front plate of the optical functional member, one release film is peeled off, and the release surface is bonded to the front plate, and the other release film is bonded. Bonding can be performed by peeling off from the adhesive composition 10. Specifically, as shown in FIG. 2 (A), the laminated body in which the adhesive composition 10 is bonded to the front plate 1a of the optical functional member is held by the lower stage 21 by suction and suction, and the LCD panel 2 Is held on the reversing stage 22 by suction suction. Then, as shown in FIGS. 2B and 2C, by reversing the reversing stage 22, the LCD panel 2 and the front plate 1 a of the optical function member are bonded together via the adhesive composition 10. Can do.

  In the present invention, after the above bonding, heat treatment under a predetermined condition is performed, the thermosetting reaction is accelerated by the organic peroxide contained in the adhesive composition, the crosslinking reaction is completed, and a desired degree of crosslinking is achieved. An adhesive cured product having is obtained. In this case, in the present invention, a monomer having low reactivity with respect to a photocuring reaction such as a methacrylic monomer contained in the adhesive composition is heat-polymerized or cross-linked to accelerate the thermosetting reaction. The adhesion and durability can be improved. When performing the thermosetting, a heating and pressing apparatus such as an autoclave or a heating press can be used as the heat treatment means (reference numeral 80 in FIG. 3). The heating temperature is preferably 50 ° C. or higher and 140 ° C. or lower and the heating time is 10 to 120 minutes. In this case, an increase in the conversion rate can be confirmed by measuring the crosslinking conversion rate by IR spectrum.

  Thus, in the present invention, both the step (1) of photocuring the adhesive composition and the step (2) of thermosetting the adhesive composition are included as essential requirements. Thus, the adhesive cured product obtained by performing the cross-linking reaction over time in two stages has a very high adhesiveness of bonding between the optical functional member and the display unit, which is unprecedented. Even in an environment of temperature change, there is almost no peeling and the durability is high.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not restrict | limited to the following Example. In addition, in the following example, a part and% show a mass part and mass%.

[Examples 1-6, Comparative Examples 1-3]
Adhesive compositions of Examples and Comparative Examples were prepared according to the formulation shown in Table 1 below. The adhesive composition was applied using a polarizing plate laminator (see FIG. 1). That is, the adhesive composition was applied to a film and laminated by a wet lamination method. The coating conditions are a speed of 0.2 m / min and a roll diameter of φ140 mm.

The photocuring conditions during the coating are as follows.
Irradiation: UV irradiation Irradiation length: 60 cm
Irradiation device: Single side irradiation with black light (12)
Irradiation energy: 1500 mJ / cm ² · 83 mW / cm ²
Irradiation time: 3 minutes

The trade names of main materials described in Table 1 are as follows.
・ Raw material resin material, acrylic adhesive mixed with acrylic polymer and monomer, manufactured by Soken Chemical Co., Ltd., trade name “Syrup B”
・ Photopolymerization initiator, product name “P-02” manufactured by Soken Chemical Co., Ltd. ・ Organic peroxide, product name “Perloyl TCP” manufactured by Nippon Oil & Fats Co., Ltd. ・ Product name “Light acrylate TMP-A” manufactured by Kyoeisha Chemical Co., Ltd. Propane triacrylate (average molecular weight Mw 296)
-Product name “Light Ester HOA” manufactured by Kyoeisha Chemical Co., Ltd., 2-hydroxyethyl acrylate (average molecular weight Mw 116)
-Product name "Light acrylate 1.6HX-A" manufactured by Kyoeisha Chemical Co., Ltd., 1,6-hexanediol diacrylate (average molecular weight Mw226)
・ Product name “Light Ester HO”, manufactured by Kyoeisha Chemical Co., Ltd., 2-hydroxyethyl methacrylate (average molecular weight Mw 130)
・ Product name “Light Ester 1.6HX” manufactured by Kyoeisha Chemical Co., Ltd., 1,6-hexanediol dimethacrylate (average molecular weight Mw254)

  The evaluation tests in Table 2 are as follows.

CURAST EVALUATION About the film-formed product (before thermosetting) after UV irradiation, the rising torque was evaluated by Curast Meter III (manufactured by JSR).
Rising torque: (Achieved torque after 60 minutes measurement)-(Lowest point)

Thermal cycle test (1) Sample preparation method Polycarbonate (2.0 mm) / Adhesion (250 μm) / Glass (1.1 mm)
Sample size: 40x50mm
Sample alignment conditions: Autoclave 60 ° C. × 0.5 MPa × 60 minutes (2) Cooling cycle conditions Exposure conditions: −10 ° C. × 24 hours (first stage)
23 ° C x 24 hours (second stage)
80 ° C x 24 hours (third stage)
23 ° C x 24 hours (4th stage)
(4) Evaluation method Two sets of the above-described configurations were produced. The combined configuration was visually observed.
○ Both sheets were defect-free x 2 sheets were visually evaluated, and even one sheet was peeled by 1 mm ² or more

In Comparative Example 1, air release during autoclaving was good, but large peeling occurred in the cold cycle test.
In Comparative Example 2, air release during autoclaving was good, but large peeling occurred in the cold cycle test.
In Comparative Example 3, the air escape during autoclave was insufficient, and large peeling occurred in the cold cycle test.

FIG. 1 (A) is a schematic view showing an example of a method for applying an adhesive composition to a release film, and FIG. 1 (B) is a portion showing a laminate of an adhesive composition-release film. It is sectional drawing. It is the schematic which showed an example of the mechanism which bonds an optical function member and a display part. It is the schematic which shows a mode that the adhesive composition was heat-cured after bonding an optical function member and a display part.

Explanation of symbols

1a Optical functional member (front plate)
2 Display unit 10 Adhesive composition 70 Irradiation source (black light)
80 Heating and pressing means (autoclave)

Claims (8)

  Adheres the optical function member and the display section of the optical function member integrated display device in which the optical function member and the display section are integrated, and contains a raw material resin material, a photopolymerization initiator and an organic peroxide as essential components. An adhesive composition for an optical functional member-integrated display device, wherein the raw material resin material is mixed with at least two types of monomers having different reactivity.   The adhesive composition for an optical functional member-integrated display device according to claim 1, wherein the two types of monomers are an acrylate monomer and a polymer having a lower reactivity than the acrylate monomer.   The adhesive composition for an optical functional member-integrated display device according to claim 1 or 2, wherein the two types of monomers are an acrylate monomer and a methacrylate monomer.   4. The adhesive composition for an optical functional member-integrated display device according to claim 1, wherein the raw material resin material is a material obtained by dissolving a raw material polymer in a low molecular weight raw material monomer.   The adhesive composition for an optical functional member-integrated display device according to claim 4, wherein the raw material polymer is contained in an amount of 5 to 80% by mass with respect to the raw material resin material.   The adhesive for an optical functional member-integrated display device according to any one of claims 1 to 5, wherein the total amount of the at least two types of monomers is 0.1 to 30 parts by mass with respect to 100 parts by mass of the raw resin material. Agent composition.   An optical functional member-integrated display device, wherein the optical functional member and the display unit are laminated via the adhesive according to any one of claims 1 to 6.   In the manufacturing method of the optical function member integrated display apparatus with which the optical function member and the display part were integrated, any one of Claims 1-6 as an adhesive composition which adhere | attaches the said optical function member and the said display part. The adhesive composition described in the above item is used, and the adhesive composition is photocured in advance to prepare a partially crosslinked adhesive composition, and then the optical functional member and the optical composition member through the adhesive composition. A manufacturing method of a display device integrated with an optical function member, wherein the display unit is bonded together, and then the adhesive composition is thermally cured by heat treatment.

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