JP5143256B2 - Adhesive optical film and plasma display panel - Google Patents

Description

  The present invention relates to an adhesive optical film and a plasma display panel, and more particularly to an adhesive optical film having a near-infrared absorbing adhesive layer and a plasma display panel having the adhesive optical film.

  The plasma display emits electromagnetic waves, neon light, and near infrared rays simultaneously with visible light because of its light emission principle. These have an undesirable effect and need to be shielded. Therefore, an optical film is used.

  In addition to the above functions, an optical film in which a number of layers are laminated has been used in order to provide various functions such as antireflection on the viewer side and improvement of contrast in order to improve image quality. As a large number of layers, for example, a layer having a near-infrared absorbing function and a layer having a neon light cut function can be used separately. However, in recent years, there is a strong demand for simplifying the layer structure of these optical films, and the cost tends to be reduced. Thus, it has been proposed to give various functions to one adhesive layer used for an optical film.

Conventionally, since the optical film has a multilayer structure, it is possible to use a resin having low reactivity with the near-infrared absorbing dye as a matrix resin including the infrared-absorbing dye (for example, Patent Document 1). ). As a result, the near-infrared absorbing dye could be stably held for a long time without causing deterioration.
However, when the near-infrared absorbing dye is contained in the adhesive layer, the adhesive resin constituting the adhesive layer easily reacts with the infrared absorbing dye and has a problem in durability.

  In order to solve this problem, it has been proposed to use two or more kinds of resins having a weight average molecular weight of 50,000 or more and different glass transition temperatures as the resin constituting the adhesive layer (for example, Patent Document 2). Various materials have been proposed as near-infrared absorbing dyes, and diimonium dyes having a wide near-infrared absorption wavelength range are often used (for example, Patent Document 2).

JP 2007-108582 A JP 2007-256758 A

It is desired that the pressure-sensitive adhesive layer containing the dimonium dye further enhances the near-infrared absorption function and has other functions. However, when other dyes such as near infrared absorbing dyes, visible light absorbing dyes or neon luminescent absorbing dyes other than the above diimonium dyes are added to the adhesive layer, near infrared absorption occurs due to decomposition (deterioration) of the diimonium dyes contained in the adhesive layer. There was a problem that the effect decreased.
This problem of dye decomposition (deterioration) occurs after the diimonium dye and various dyes are mixed in the adhesive layer, and there is a problem that the initial absorption spectrum of the adhesive optical film in the near infrared region is deteriorated.

  Therefore, the present invention provides a near-infrared absorbing adhesive layer containing a diimonium dye, and the above near-infrared absorption even when other dyes such as a near-infrared absorbing dye, a visible light absorbing dye, a neon luminescent absorbing dye other than the diimonium dye are added. It is an object of the present invention to provide means that can improve the initial absorption spectrum of an adhesive optical film having an adhesive layer.

  The present invention has solved the above problems by the following technical configuration.

An acrylic polymer, a diimonium dye, a dye other than the diimonium dye, a near-infrared absorbing adhesive layer containing a silane coupling agent represented by the following formula (4), and a base material layer, The pressure-sensitive adhesive optical film is characterized in that a dye aggregate having an aggregate diameter of 100 μm or less is present in the near-infrared absorbing adhesive layer.

（式中ｎは２０〜２４の整数である。）

(In the formula, n is an integer of 20 to 24.)

  In the near-infrared absorbing pressure-sensitive adhesive layer, it is preferable that the number of dye aggregates having an aggregate diameter of more than 100 μm contained in 400 μm square is 3 or less.

  The other dye is preferably at least one selected from near-infrared absorbing dyes, visible light absorbing dyes, and neon luminescent absorbing dyes other than the diimonium dye.

  The number average molecular weight (Mn) of the silane coupling agent is preferably 500 or more.

  The weight average molecular weight (Mw) of the silane coupling agent is preferably 5000 or more.

  It is preferable that Mw / Mn, which is the ratio of the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the silane coupling agent, is 3 or more and 15 or less.

  The silane coupling agent is preferably contained in an amount of 0.002 parts by mass to less than 0.2 parts by mass with respect to 100 parts by mass of the acrylic polymer.

  It is preferable that the acid value of the acrylic polymer is 7 to 50 mgKOH / g.

  The near-infrared absorbing adhesive layer is one or two or more crosslinking agents selected from the group consisting of epoxy crosslinking agents, isocyanate crosslinking agents, amine crosslinking agents, imine crosslinking agents, and peroxide crosslinking agents. It is preferable to contain the combination of these.

  The near-infrared absorbing adhesive layer preferably contains a rust inhibitor.

  It is preferable that a metal mesh film is adhered to the near infrared absorbing adhesive layer.

  It is a plasma display panel in which the adhesive optical film is attached to the surface.

According to the present invention, the addition of other dyes such as a near-infrared absorbing dye, a visible light absorbing dye, and a neon luminescent absorbing dye other than the diimonium dye can prevent the deterioration of the diimonium dye. The initial absorption spectrum can be improved.
Moreover, according to this invention, since the initial absorption spectrum of an adhesive optical film can be made favorable, more near-infrared light can be absorbed more.
In addition, since the adhesive layer can have an infrared absorption function and other functions (toning function, neon light emission absorption function, etc.), the number of layers as an optical film can be reduced.

Schematic diagram of the near-infrared absorbing adhesive layer constituting the adhesive optical film observed with an optical microscope

[Adhesive optical film]
The pressure-sensitive adhesive optical film according to the present invention includes a near-infrared absorbing pressure-sensitive adhesive layer (hereinafter sometimes simply referred to as “pressure-sensitive adhesive layer”) containing an acrylic polymer, a diimonium dye, and a dye other than the diimonium dye. And a base material layer. The near infrared absorbing pressure-sensitive adhesive layer contains a dye aggregate having an aggregate diameter of 100 μm or less. The aggregates may be uniformly dispersed in the near-infrared absorbing pressure-sensitive adhesive layer, but may be scattered with some unevenness as long as the optical properties are impaired. The dye aggregate is at least one selected from an aggregate of diimonium dyes, an aggregate of diimonium dyes and other dyes, and an aggregate of other dyes, and may contain two or three kinds. In addition, as shown in the Example mentioned later, the "initial absorption spectrum" in this specification is a layer structure in which a release film is laminated on both surfaces of a near-infrared absorbing adhesive layer, and after curing at 40 ° C for 3 days. The transmittance in the near infrared region (800 nm to 950 nm).

  Although the lower limit of the aggregate diameter of the dye aggregate is not particularly limited, it is, for example, 0.01 μm. A preferable lower limit is 0.1 μm, more preferably 1 μm, and particularly preferably 10 μm. Although depending on various components contained in the near-infrared absorbing adhesive layer, the initial absorption spectrum of the adhesive optical film having a diimonium dye-containing adhesive layer is preferred when the lower limit of the aggregate diameter of the dye aggregate is increased to some extent. It will be a thing.

The dye aggregate can be observed with an optical microscope. The aggregate diameter and number of dye aggregates are determined from the aggregates present in a 400 μm square (FIG. 1).
FIG. 1 is a schematic view of a near-infrared absorbing adhesive layer constituting an adhesive optical film observed with an optical microscope. The near-infrared absorbing adhesive layer 3 is composed of a dye aggregate 1 and a matrix 2, and the matrix 2 exists in the gap between the dye aggregates 1. The matrix 2 is mainly an acrylic polymer. In the present invention, the aggregate diameter d of the dye aggregate is represented by the major axis of the dye aggregate 1.
The dye aggregate 1 takes various shapes, for example, a circular shape, a triangular shape, a quadrangular shape, a polygonal shape, an indeterminate shape, etc. And the shape of an aggregate such as an aggregate of radial objects. When these aggregates are aggregates, the aggregate diameter d can be measured by applying these aggregates as the aggregate 1 shown in FIG.

The near-infrared absorbing adhesive layer preferably does not substantially contain a dye aggregate having an aggregate diameter of more than 100 μm. Specifically, the pressure-sensitive adhesive optical film is observed with an optical microscope, and the number of dye aggregates having an aggregate diameter of more than 100 μm is preferably 3 or less, and preferably 2 or less in a 400 μm square frame. Is more preferable, it is more preferable that it is 1 or less, and it is particularly preferable that it is not included at all. When present as a dye aggregate having an aggregate diameter of more than 100 μm, the initial absorption spectrum of the pressure-sensitive adhesive optical film is deteriorated.
The number of dye aggregates having an aggregate diameter of 50 μm or more and 100 μm or less is preferably 100 or less.
The number of dye aggregates having an aggregate diameter of less than 50 μm is not particularly limited because it does not affect the initial absorption spectrum of the pressure-sensitive adhesive optical film.

(Adhesive composition)
The near infrared absorbing pressure-sensitive adhesive layer according to the present invention is preferably formed of a pressure-sensitive adhesive composition containing an acrylic polymer, a silane coupling agent, and a diimonium dye. The pressure-sensitive adhesive composition preferably has an amine additive content of 1 part by mass or less with respect to 100 parts by mass of the acrylic polymer, and the acrylic polymer has an acid value of 7 to 50 mgKOH / g. It is. When the acid value of the acrylic polymer is within the above range under the condition that the amine additive is hardly contained (the content of the amine additive is 1 part by mass or less with respect to 100 parts by mass of the acrylic polymer). The initial absorption spectrum of the diimonium dye contained in the adhesive layer is improved. In particular, when the content of the amine-based additive exceeds 1 part by mass with respect to 100 parts by mass of the acrylic polymer, the diimonium dye reacts with the amine and decomposes.

  In addition, 15-50 mgKOH / g is suitable for an acid value, and 20-40 mgKOH / g is more suitable. By setting it as such a range, the near-infrared absorption adhesion layer in which the initial absorption spectrum of a diimonium pigment | dye is favorable can be obtained.

  Moreover, although various additives can be added to the adhesive composition according to the present invention, it is preferable that the adhesive composition does not substantially contain an amine-based additive. “Substantially not contained” means that each component constituting the pressure-sensitive adhesive composition may contain other components in addition to the main component, and exclude the other components. When an amine-based substance is added, there is a possibility that the diimonium dye and the amine react to decompose the diimonium dye before the initial absorption spectrum is measured. The amine-based additive means a substance having an aggressive unshared electron pair on a nitrogen atom, such as a primary amine, a secondary amine, or a tertiary amine. Examples of the amine-based additive include amine-containing tackifiers. The amine-based additive is preferably 1 part by mass or less, more preferably 0.1 part by mass or less, and particularly preferably 0.01 part by mass or less with respect to 100 parts by mass of the acrylic polymer.

Acrylic polymer The acrylic polymer according to the present invention preferably contains at least an alkyl (meth) acrylate monomer, and at least one selected from a carboxyl group-containing monomer and a hydroxyl group-containing monomer and the alkyl (meth) acrylate. More preferably, it is obtained by polymerizing with a monomer. Among these polymers, an acrylic polymer obtained by polymerizing an alkyl (meth) acrylate {(meth) acrylic acid alkyl ester} monomer having an alkyl group with 4 to 12 carbon atoms and a carboxyl group-containing monomer is used. It is preferable to do. The acrylic polymer is preferably contained in an amount of 50 parts by mass or more with respect to 100 parts by mass of the solid component of the near-infrared absorbing adhesive layer, and more preferably in the range of 60 to 99.9 parts by mass.

  Although it does not restrict | limit especially as alkyl (meth) acrylate (alkyl acrylate, alkyl methacrylate), For example, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl ( (Meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl ( Examples include meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, and dodecyl (meth) acrylate. In addition, the alkyl (meth) acrylate as a monomer component can be used individually or in combination of 2 or more types. Of these acrylates, n-butyl (meth) acrylate alone is particularly suitable. Although content of alkyl (meth) acrylate should just be 1-100 mass% in 100 mass parts of acrylic polymers, 50-99 mass% is suitable, and 70-98 mass% is still more suitable.

  Although it does not specifically limit as a carboxyl group-containing monomer, For example, (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, etc. are mentioned. In addition, anhydrides of these carboxyl group-containing monomers can also be used as the carboxyl group-containing monomer. Although it can set arbitrarily as a ratio of a carboxyl group-containing monomer according to the value of the above-mentioned acid value, for example, 1 to 24 mass% is suitable in 100 mass parts of acrylic polymers, and 3 to 20 mass% is Further preferred.

  Although the monomer component of the acrylic polymer has been described, it is preferable that no hydroxyl group (OH group) is included among these compositions. By not having a hydroxyl group in this way, the diimonium dye in the pressure-sensitive adhesive composition becomes difficult to decompose, and the initial absorption spectrum of the dye becomes good. Although not particularly limited, the hydroxyl group-containing monomer contained in the pressure-sensitive adhesive composition of the present invention is preferably 10% by mass or less and more preferably 1% by mass or less in 100 parts by mass of the acrylic polymer. Yes, it is more preferably 0.1% by mass or less, and particularly preferably 0.01% by mass or less.

  The acrylic polymer can be produced by a known polymerization method, and examples thereof include a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, and a polymerization method by ultraviolet irradiation. In addition, known polymerization initiators, chain transfer agents, and the like used in the polymerization can be appropriately used.

  The weight average molecular weight of the acrylic polymer is preferably 100,000 to 2,000,000, more preferably 300,000 to 1,500,000, and even more preferably 400,000 to 1,200,000.

The acrylic polymer preferably has a glass transition temperature of less than 0 ° C., and is preferably less than −20 ° C. because the adhesiveness is further improved. The glass transition temperature is a shoulder value measured by a differential scanning calorimeter (DSC).
By including a silane coupling agent in the adhesive layer, even if an acrylic polymer having a low glass transition temperature is used, the initial absorption spectrum of the diimonium dye becomes good, and the aggregate diameter of the dye aggregate is 100 μm or less. can do.

Silane Coupling Agent A silane coupling agent is generally used as an intermediary for linking an organic material and an inorganic material that have two or more different functional groups in the molecule and are usually difficult to bond. For example, since a silane coupling agent can connect an acrylic polymer (organic material) contained in the pressure-sensitive adhesive and a glass (inorganic material) to which the pressure-sensitive adhesive layer is bonded, the adhesive strength and reworkability are adjusted. It is common to use for this purpose.

  By including a silane coupling agent in the adhesive layer containing the acrylic polymer and the near infrared absorbing dye, the initial absorption spectrum of the near infrared absorbing dye can be improved. That is, the present invention has been made by finding an action / effect that cannot be predicted from the action / effect of a conventional silane coupling agent-containing adhesive layer.

Preferable silane coupling agents include those represented by the following general formula ( 4 ).

（式中ｎは２０〜２４の整数である。）

(In the formula, n is an integer of 20 to 24.)

In the general formula (4), by an n-alkoxy group having 20-24 carbon atoms _(CH 2 -O), it can be preferably an initial absorption spectrum of the diimmonium dye. When the silane coupling agent is not contained in the adhesive layer containing the diimonium dye and the other dye, the aggregate diameter of the dye aggregate is more than 100 μm. On the other hand, when a silane coupling agent is contained in an adhesive layer containing a diimonium dye and another dye, the aggregation diameter of the dye aggregate can be reduced to 100 μm or less, so that the aggregation of the dye is inhibited by the silane coupling agent. It is thought that. The reason for this is not clear, but the silane coupling agent in the adhesive layer can be moved by setting the carbon number of (CH ₂ —O) in the silane coupling agent represented by the general formula ( 4 ) to 20 to 24. Therefore, it is considered that a silane coupling agent is easily present between the aggregated dyes, and as a result, aggregation of the dyes is prevented.

  The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the silane coupling agent used in the present invention are both larger than those of a normal silane coupling agent used for imparting adhesiveness and reworkability. It is preferable to use one.

The number average molecular weight (Mn) of the silane coupling agent used in the present invention is preferably 500 or more, more preferably 800 or more, further preferably 900 or more, and more preferably 1000 or more. Particularly preferred. When Mn is 500 or more, aggregation of pigments can be prevented. Further, as Mn increases, the aggregation of the dye can be prevented more effectively, and the initial absorption spectrum of the diimonium dye can be made preferable.
Although the upper limit of a number average molecular weight (Mn) is not specifically limited, For example, it is 20000. If Mn becomes too large, it may take a long time to synthesize, or the dispersibility in the adhesive layer may be low, making it difficult to obtain uniform optical characteristics.

The weight average molecular weight (Mw) of the silane coupling agent used in the present invention is preferably 5000 or more, more preferably 8000 or more, further preferably 9000 or more, and preferably 10,000 or more. Particularly preferred. When Mw is 5000 or more, aggregation of the dye can be prevented. Further, as Mw increases, the aggregation of the dye can be more effectively prevented and the initial absorption spectrum of the diimonium dye can be made preferable.
Although the upper limit of a weight average molecular weight (Mw) is not specifically limited, For example, it is 200000. If Mw becomes too large, synthesis may take time, and dispersibility in the adhesive layer may be reduced, making it difficult to obtain uniform optical characteristics.

The dispersity (Mw / Mn) of the silane coupling agent used in the present invention is preferably wide because it is easy to prevent aggregation of the dye.
Mw / Mn is preferably 3 or more and 15 or less, more preferably 4 or more and 14 or less, and further preferably 5 or more and 13 or less.

The upper limit of the amount of the silane coupling agent used is preferably less than 0.2 parts by weight, more preferably 0.05 parts by weight or less, with respect to 100 parts by weight of the acrylic polymer. More preferably, it is at most part by mass. When 0.2 mass part or more is included, when a release film is laminated on the pressure-sensitive adhesive layer, the adhesive force may be improved and the release film may be difficult to peel off.
The lower limit of the amount of the silane coupling agent used is preferably 0.002 parts by mass or more, more preferably 0.005 parts by mass or more, based on 100 parts by mass of the acrylic polymer. More preferably, it is at least part by mass. When the amount is less than 0.002 parts by mass, it is difficult to prevent aggregation of the dye, and the initial absorption spectrum of the diimonium dye is not preferable.

  Examples of silane coupling agents that are normally used other than the silane coupling agent used in the present invention include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 2- (3,4-epoxycyclohexyl). ) Silicon compounds having an epoxy structure such as ethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropyl (Meth) acryl such as amino group-containing silicon compounds such as methyldimethoxysilane, 3-chloropropyltrimethoxysilane, acetoacetyl group-containing trimethoxysilane, 3-acryloxypropyltrimethoxysilane, and 3-methacryloxypropyltriethoxysilane Group-containing Coupling agent, such as an isocyanate group-containing silane coupling agents such as 3-isocyanate propyl triethoxysilane and the like. In particular, 3-glycidoxypropyltrimethoxysilane and acetoacetyl group-containing trimethoxysilane are preferably used because peeling can be effectively suppressed.

Diimonium Dye The pressure-sensitive adhesive composition according to the present invention contains a diimonium dye. Diimonium dyes include those in which a diimonium dye is dissolved by adding a solvent, those in which crystals are dispersed without being dissolved even when a solvent is added, and several to several tens of diimonium dye molecules in the presence of a solvent. For example, a collection of about one piece. The dissolution state of the dye varies depending on the structure of the diimonium dye (type of functional group) and the type of solvent or combination of solvent types. As the solvent, a good solvent or a poor solvent may be used alone, or a combination of both may be used, or a plurality of types of good solvents or a plurality of types of poor solvents may be used. Among the diimonium dyes, it is preferable to have a diimonium cation represented by the following formula (2).

  More specific examples of general formula R include, for example, methyl, ethyl, n-propyl, n-butyl, iso-butyl, sec-butyl, t-butyl, n-pentyl, iso -Linear or branched alkyl group such as -pentyl group, t-pentyl group, n-hexyl group, n-octyl group, cyclopentylmethyl group, cyclohexylmethyl group, 2-cyclopentylethyl group, 2-cyclopentylpropyl group, 3- Cyclic alkyl groups such as cyclopentylpropyl group, 4-cyclopentylbutyl group, 2-cyclohexylethyl group, 2-cyclohexylpropyl group, 3-cyclohexylpropyl group, 4-cyclohexylbutyl group, cyanomethyl group, 2-cyanoethyl group, 3-cyano Propyl group, 2-cyanopropyl group, 4-cyanobutyl group, 3-cyanobutyl Group, 2-cyanobutyl group, 5-cyanopentyl group, 4-cyanopentyl group, 3-cyanopentyl group, 2-cyanopentyl group, 6-cyanohexyl group, 5-cyanohexyl group, 4-cyanohexyl group, Cyano-substituted (C1-C8) alkyl groups such as 3-cyanohexyl group and 2-cyanohexyl group, phenyl group, naphthyl group, anthracenyl group, methoxymethyl, 2-methoxyethyl, 3-methoxypropyl, 2-methoxypropyl, 4-methoxybutyl, 3-methoxybutyl, 2-methoxybutyl, 5-methoxypentyl, 4-methoxypentyl, 3-methoxypentyl, 2-methoxypentyl, 6-methoxyhexyl, ethoxymethyl, 2-ethoxyethyl, 3- Ethoxypropyl, 2-ethoxypropyl, 4-ethoxybutyl, 3-ethoxy Linear or branched alkoxyalkyl groups such as butyl, 5-ethoxypentyl, 4-ethoxypentyl, 6-ethoxyhexyl, propoxymethyl, 2-propoxyethyl, 3-propoxypropyl, 4-propoxybutyl, 5-propoxypentyl, Trifluoromethyl group, 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, 5,5,5-trifluoropentyl group, 6 , 6,6-trifluorohexyl group, 8,8,8-trifluorooctyl group, 2-methyl-3,3,3-trifluoropropyl group, perfluoroethyl group, perfluoropropyl group, perfluorobutyl group, perfluorohexyl Group, perfluorooctyl group, 2-trifluoro-propyl group, trichloro Methyl group, 2,2,2-trichloroethyl group, 3,3,3-trichloroolopropyl group, 4,4,4-trichlorobutyl group, 5,5,5-trichloropentyl group, 6,6,6- Trichlorohexyl group, 8,8,8-trichlorooctyl group, 2-methyl-3,3,3-trichloropropyl group, perchloroethyl group, perchloropropyl group, perchlorobutyl group, perchlorohexyl group, perchloro Octyl group, 2-trichloro-perchloropropyl group, tribromomethyl group, 2,2,2-tribromoethyl group, 3,3,3-tribromopropyl group, 4,4,4-tribromobutyl group, 5,5,5-tribromopentyl group, 6,6,6-tribromohexyl group, 8,8,8-tribromooctyl group, 2-methyl-3,3,3-tribromopropyl , Halogenated alkyl groups such as, but not limited to, perbromoethyl group, perbromopropyl group, perbromobutyl group, perbromohexyl group, perbromooctyl group, 2-tribromo-perbromopropyl group, etc. It is not a thing.

  The kind of counter anion in the diimonium dye is not particularly limited. As counter anions, for example, halogen ions such as fluorine ion, chlorine ion, bromine ion, iodine ion, perchlorate ion, periodate ion, tetrafluoroborate ion, hexafluorophosphate ion, Hexafluoroantimonate ion, trifluoromethanesulfonate ion, toluenesulfonate ion, bis (trifluoromethanesulfone) imide ion, tetrakis (pentafluorophenyl) borate ion, tris (trifluoromethanesulfone) methide ion, sulfone Examples thereof include an imide anion.

  Among these, a sulfonimide anion is particularly preferable, and a fluorine-containing sulfonimide anion represented by the following general formula (3) is particularly preferable. By using the fluorine-containing sulfonimide anion in this way, it becomes particularly easy to form an aggregate.

但し、式（３）中、Ｒ^ａ、Ｒ^ｂは、同一または異なってもよい、フッ素原子またはフッ化アルキル基を示す。Ｒ^ａ、Ｒ^ｂとしては前記置換基であれば特に限定されないが、炭素数１〜８のフッ化アルキルが挙げられる。

However, in formula (3), R ^a and R ^b represent a fluorine atom or a fluorinated alkyl group, which may be the same or different. Although it will not specifically limit if it is the said substituent as R ^<a> , R ^<b >, C1-C8 fluorinated alkyl is mentioned.

  The diimonium dye can be produced by a known method. For example, bis (fluorosulfonyl) imidic acid prepared according to the method described in JP-A-8-511274, US Pat. No. 5,874,616, etc. The fluorinated alkanesulfonyl-fluorosulfonylimidic acid prepared according to the above is used as an anion component, and silver is allowed to act on this to form silver bis (fluorosulfonyl) imidate or silver fluoride alkanesulfonyl-fluorosulfuroimidate. The dimonium compound is reacted in an organic solvent such as N-methyl-2-pyrrolidone, dimethylformamide, acetonitrile, etc. at a temperature of 30 to 150 ° C., and the precipitated silver is filtered off, followed by a solvent such as water, ethyl acetate or hexane. And the resulting precipitate can be synthesized by filtration.

  Commercially available diimonium dyes include trade name “CIR-1085” manufactured by Nippon Carlit Co., Ltd., trade name “CIR-1085F” manufactured by Nippon Carlit Co., Ltd., and trade name “KAYASORB IRG-022” manufactured by Nippon Kayaku Co., Ltd. ", Trade name" KAYASORB IRG-023 "manufactured by Nippon Kayaku Co., Ltd. and the like.

  There is no particular limitation on the amount of the dimonium dye added to the solid content ratio of the near-infrared absorbing adhesive layer, and it can be arbitrarily selected according to the required performance. It is suitable to make it into 0.1-20 mass parts.

Optional components Various other known additives can be added to the pressure-sensitive adhesive composition according to the present invention, but crosslinking agents, tackifiers, plasticizers, glass fibers, glass beads, metal powders, and other inorganic substances A filler made of powder or the like, a pigment, a colorant, a filler, an antioxidant, an ultraviolet absorber, or the like can also be used. Moreover, it is good also as a near-infrared absorption adhesive layer etc. which contain microparticles | fine-particles and show light diffusivity. Other near-infrared absorbing dyes may be added to the pressure-sensitive adhesive composition according to the present invention. Further, a visible light absorbing dye may be added to adjust the color tone. In addition, it is preferable that a rust inhibitor is added.

Cross-linking agent The pressure-sensitive adhesive composition according to the present invention preferably contains a cross-linking agent. Examples of the crosslinking agent include an epoxy crosslinking agent, an isocyanate crosslinking agent, an imine crosslinking agent, and a peroxide crosslinking agent. Among these, an epoxy-based crosslinking agent and an isocyanate-based crosslinking agent are preferable.

  The epoxy-based crosslinking agent contains an epoxy compound, and examples of the epoxy compound include glycerin diglycidyl ether. The amount of the epoxy crosslinking agent used is 0.001 to 2 parts by mass, preferably 0.01 to 1 part by mass, and more preferably 0.02 to 0.5 parts by mass with respect to 100 parts by mass of the acrylic polymer. is there. When the amount of the epoxy compound used is less than 0.001 part by mass, it is not preferable in terms of adhesion to the optical film and durability.

  The isocyanate-based crosslinking agent contains an isocyanate compound. Examples of the isocyanate compound include tolylene diisocyanate, chlorophenylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, water. Added isocyanate monomers such as diphenylmethane diisocyanate, adduct isocyanate compounds obtained by adding these isocyanate monomers with polyhydric alcohols such as trimethylolpropane, isocyanurates, burette type compounds, as well as known polyether polyols, polyester polyols, acrylics Polyol, polybutadiene polyol, polyisoprene polyol, etc. And addition-reacted urethane prepolymer type isocyanate. Among these isocyanate compounds, adduct isocyanate compounds such as xylylene diisocyanate are preferable from the viewpoint of improving adhesion to an optical film.

  The amount of the isocyanate crosslinking agent used is 0.001 to 5 parts by weight, preferably 0.01 to 3 parts by weight, more preferably 0, based on 100 parts by weight of the acrylic polymer. 0.02 to 2.5 parts by mass. When the amount of the isocyanate compound used is less than 0.001 part by mass, it is not preferable in terms of adhesion to the optical film and durability.

Other dyes that can be used in combination with other dyes include near-infrared absorbing dyes, visible light absorbing dyes, neon luminescent absorbing dyes, and the like.

  Other near infrared absorbing dyes that can be used in combination include known cyanine dyes, polymethine dyes, squarylium dyes, porphyrin dyes, metal dithiol complex dyes, phthalocyanine dyes, diimonium dyes, inorganic oxide particles, etc. Can be mentioned.

  Other preferred dyes (dyes other than diimonium dyes) are dyes that can exhibit a quencher effect with respect to the diimonium dye. The quencher effect is an effect of deexciting an active molecule in an excited state. In the present invention, other dyes having an effect of de-exciting and stabilizing diimonium dye molecules, diimonium anions or diimonium cations are preferred. From the viewpoint of the quencher effect, a phthalocyanine dye is preferable as the other dye.

  Although the compounding quantity of other pigment | dye (near-infrared absorption pigment | dye, neon luminescence absorption pigment | dye, visible light absorption pigment | dye) is not specifically limited, It is 0.001-5 mass parts with respect to 100 mass parts of acrylic polymers. Preferably there is. When a plurality of other dyes are used, the amount is within the above range for each dye.

Visible light absorbing dye Further , in order to adjust the color tone of the pressure-sensitive adhesive composition, a visible light absorbing dye for toning may be added. This is because the color tone of the image display unit is normally preferably neutral gray. Neutral gray means that in the hue display by Lab, the a value and the b value are hues substantially close to zero. More specifically, it means a hue in which the a value and the b value are within a range of ± 5. More preferably, a hue having an a value within ± 3 and a b value within ± 4 is preferably used. More preferably, a hue having an a value in the range of +1 to −2.5 and a b value within ± 3.5 is preferably used. When the a value and the b value exceed the above range, particularly ± 5 range, the display color of the display is affected, and the color reproducibility is deteriorated. Examples of the dye include isoindolinone, anthraquinone, dioxazine, azo, naphthol, quinophthalone, azomethine, benzimidazolone, perinone, pyranthrone, quinacridone, perylene, pyranthrone, phthalocyanine And selenium. These dyes can also be used by appropriately mixing in order to adjust to the target hue. Specifically, 1: 2 chromium complex, 1: 2 cobalt complex, copper phthalocyanine, anthraquinone, diketopyrrolopyrrole and the like can be used. More specifically, Orazol Blue GN (manufactured by Ciba Specialty Chemicals), Orazol Blue BL (manufactured by Ciba Specialty Chemicals), Orazol Red 2B (manufactured by Ciba Specialty Chemicals), Orazol Red G ( Ciba Specialty Chemicals), Orazole Black CN (Ciba Specialty Chemicals), Orazole Yellow 2GLN (Ciba Specialty Chemicals), Orazole Yellow 2RLN (Ciba Specialty Chemicals), Microlith DPP Red BK (manufactured by Ciba Specialty Chemicals), and the like.

Neon luminescence absorbing dye The pressure-sensitive adhesive composition according to the present invention preferably uses a neon luminescence absorbing dye having a maximum absorption wavelength of 550 to 650 nm in order to absorb unnecessary neon luminescence. The neon luminescence absorbing dye is not particularly limited, and examples thereof include a cyanine dye and a tetraazaporphyrin dye. Commercially available neon light-absorbing dyes include Adeka Arcles TY-102 (Asahi Denka Kogyo Co., Ltd.), Adeka Arcles TY-14 (Asahi Denka Kogyo Co., Ltd.), Adeka Arcles TY-15 (Asahi Denka Kogyo Co., Ltd.) TAP-2 (manufactured by Yamada Chemical Industries), TAP-18 (manufactured by Yamada Chemical Industries), TAP-45 (manufactured by Yamada Chemical Industries), trade names NK-5451 (manufactured by Hayashibara Biochemical Laboratories), NK-5532 (Manufactured by Hayashibara Biochemical Research Institute), NK-5450 (manufactured by Hayashibara Biochemical Research Institute), PD-320 (manufactured by Yamamoto Kasei Co., Ltd.) and the like. The addition amount of the neon luminescence absorbing dye varies depending on the kind of the dye, but it is preferable that the neon emission absorbing dye is added so that the transmittance at the maximum absorption wavelength is about 20 to 80%.

As the rust inhibitor , any of an inorganic rust inhibitor and an organic rust inhibitor can be used. Examples of the inorganic rust preventive include sodium nitrite and sodium chromate. Examples of the organic rust preventive include benzotriazole, octadecylamine and the like. Among these rust inhibitors, it is preferable to use a benzotriazole compound, and it is more preferable to use 1,2,3-benzotriazole.

(Base material layer)
Although it does not specifically limit as a base material, For example, a peeling base material and a translucent base material are mentioned. Moreover, a translucent base material may be provided on one side of the near-infrared absorbing pressure-sensitive adhesive layer, a release base material may be provided on the opposite surface, and a peeling base material layer may be provided on both sides of the near-infrared absorbing pressure-sensitive adhesive layer. Good. The release substrate is not particularly limited, and examples thereof include glassine paper, craft paper laminated with silicone-treated polyethylene, and silicone-treated polyethylene terephthalate (PET).

  Although it does not specifically limit as a translucent base material, For example, olefin polymers, such as glass, cyclopolyolefin, and amorphous polyolefin, methacrylic polymers, such as polymethyl methacrylate, vinyl polymers, such as vinyl acetate and a vinyl halide And polyester such as PET, polycarbonate, polyvinyl acetal such as butyral resin, polyaryl ether resin, lactone ring-containing resin film, triacetyl cellulose (TAC) and the like. Furthermore, the translucent base material includes surface treatment by a conventionally known method such as corona discharge treatment, flame treatment, plasma treatment, glow discharge treatment, surface roughening treatment, chemical treatment, anchor coating agent, primer, etc. A coating may be applied. In addition, a known additive, a heat resistant anti-aging agent, a lubricant, an antistatic agent and the like may be blended in the base resin constituting the translucent base material. The translucent substrate is formed into a film or a sheet using a known method such as injection molding, T-die molding, calendar molding, compression molding, or a method of melting and casting in an organic solvent. The base material constituting the translucent base material may be unstretched or stretched, or may be laminated with another base material.

  A PET film is preferable as the translucent substrate in the case of obtaining a near-infrared absorbing pressure-sensitive adhesive layer by a coating method, and a PET film subjected to an easy adhesion treatment is particularly preferable. Specifically, Cosmo Shine A4300 (manufactured by Toyobo), Lumirror U34 (manufactured by Toray), Melinex 705 (manufactured by Teijin DuPont) and the like can be mentioned. Moreover, functional films such as a TAC (triacetylcellulose) film, an antireflection film, an antiglare film, an impact absorbing film, an electromagnetic wave shielding film (including a mesh film), and an ultraviolet absorbing film can also be used as the translucent substrate. . Thereby, the optical filter for thin displays and optical semiconductor elements can be produced simply. The translucent substrate is preferably a film.

  Among these, glass, PET film, lactone ring-containing resin film, easy-adhesive PET film, TAC film, antireflection film and electromagnetic wave shielding film are preferably used as the translucent substrate. Although the thickness of a base material layer is not specifically limited, 0.1 micrometer-10 mm are suitable.

  In addition, any layer may be formed as an arbitrary layer, but it is preferable that a metal mesh film is attached to the surface of the near-infrared absorbing adhesive layer in order to shield electromagnetic waves. Although it does not specifically limit as a metal mesh film, For example, a copper metal mesh film is mentioned. Here, the mesh film to be attached to the surface of the near-infrared absorbing pressure-sensitive adhesive layer is suitable because it can be laminated with another layer if it is applied in such a manner that it is embedded in the pressure-sensitive adhesive layer.

[Production method]
Although the adhesive optical film which concerns on this invention is not specifically limited, For example, the coating process (coating) containing an adhesive composition and a solvent is applied on a base material, The said coating process The near-infrared absorbing adhesive layer can be formed by a drying process for drying the formed coating film. Moreover, you may provide an aging process after the said drying process as needed.

Coating process In a coating process, the coating liquid containing an adhesive composition is apply | coated on a base material. Here, the coating liquid may contain an adhesive composition and a solvent. Moreover, the said crosslinking agent and the silane coupling agent may be contained in the coating liquid. As the solvent, known solvents can be used. For example, methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, methanol, ethanol, n-propanol, isopropanol, etc. Can be given. These solvents may be used alone or in combination of two or more. As a coating method, it can be applied by a known method, but can be applied using, for example, an applicator.

In the drying step , the solvent contained in the coating film obtained in the coating step is removed and dried. The drying method is not particularly limited because a known method can be used. For example, the drying method can be performed using an oven.

Aging process In the aging process, the components in the adhesive layer can be stabilized by aging (aging) the obtained film.

[how to use]
The obtained adhesive optical film is used for a plasma display panel. That is, it can be used as a near-infrared absorbing filter by being attached to the glass panel surface of the plasma display panel. In particular, according to the pressure-sensitive adhesive optical film of the present invention, the initial absorption spectrum of the diimonium dye becomes good, and more light in the near infrared region can be absorbed. Moreover, since it is possible to give the adhesive layer near-infrared absorbing ability, the layer structure of the optical film can be reduced, and an optical film with lower cost can be obtained.

  When used for a plasma display, it may have a neon cut function as well as a near-infrared absorbing ability. That is, a neon light-absorbing dye may be added to the pressure-sensitive adhesive composition.

In addition, when using it for plasma displays, a copper mesh film may be used to cut electromagnetic waves, and this mesh film and the adhesive film's near-infrared absorbing adhesive layer are bonded together and used as an adhesive optical film. However, it is possible to prevent oxidation of copper by using a rust inhibitor. In this application, a benzotriazole compound is particularly suitable as a rust preventive agent, and 1,2,3-benzotriazole is further preferably used.
Hereinafter, description will be made using examples. In addition, “part” used in the examples means “part by mass”.

<Production example: adhesive resin>
As monomers, butyl acrylate (567.5 parts) and acrylic acid (32.5 parts) were weighed and mixed thoroughly to obtain a polymerizable monomer mixture (1). 160 parts of ethyl acetate and 300 parts of polymerizable monomer mixture (1) were placed in a flask. Also, 300 parts of the polymerizable monomer mixture (1), 16 parts of ethyl acetate, and 0.15 parts of Nyper BMT-K40 (polymerization initiator, manufactured by NOF Corporation) are placed in the dropping funnel and mixed well. A mixture (2) was prepared. While flowing nitrogen gas at a rate of 20 ml / min, the internal temperature of the flask was raised to 95 ° C., and Niper BMT-K40 (0.15 part), which is a polymerization initiator, was charged into the flask to initiate the polymerization reaction. The dropping mixture (1) was dropped from the dropping funnel over 90 minutes. After completion of the dropwise addition of the mixture for dripping (1), the mixture was aged for 6 hours while diluting with ethyl acetate in accordance with the increase in viscosity to obtain an acrylic polymer. After completion of the reaction, a pressure-sensitive adhesive resin A having a weight average molecular weight of 600,000 and an acid value of 25 was obtained.

  Various values were measured by the following methods.

(Acid value)
Take a predetermined amount of sample in a container and add solvent to dissolve well.
Titration is performed with a 0.1 mol / L potassium hydroxide ethanol solution using a potentiometric titrator, and the inflection point of the obtained titration curve is set as the end point.
Acid value (mgKOH / g) = (A × f × 5.61) / S
A: Consumption of 0.1 mol / L potassium hydroxide solution at the end point (mL)
f: Factor of 0.1 mol / L potassium hydroxide solution S: Sampling amount (g)

(Molecular weight of adhesive resin)
For the number average molecular weight (Mn) and the weight average molecular weight (Mw), the sample was weighed to 0.01 part, added to 10 parts of tetrahydrofuran (THF), and allowed to stand for 24 hours for dissolution. Each molecular weight of this solution was measured from a calibration curve prepared with standard polystyrene using a gel permeation chromatography (GPC) method.
(Measurement condition)
Device name: Tosoh Corporation, HLC-8220GPC
Sample concentration: 0.1% by weight (THF solution)
Sample injection volume: 20 μl
Eluent: THF
Flow rate: 0.300 ml / min
Measurement temperature: 40 ° C
Column: sample column; TSKguardcolumn SuperHZ-L (1) + TSKgel SuperHZM-M (2), reference column; TSKgel SuperH-RC (1), Tosoh detector: differential refractometer (RI)

(Molecular weight of silane coupling agent)
For the number average molecular weight (Mn) and the weight average molecular weight, the solvent in which the sample was diluted was removed by an evaporator, 10 ml of tetrahydrofuran (THF) was added to 20 mg of the sample after the solvent was removed, and the mixture was allowed to stand for 3 hours for dissolution. After removing foreign matter etc. with 0.45μm syringe filter, this solution is measured by gel permeation chromatography (GPC) method using standard polystyrene, propylbenzene and benzene. did.
(Measurement condition)
Sample concentration: 0.1% by weight (THF solution)
Sample injection volume: 150 μl
Eluent: THF
Flow rate: 1.0 ml / min
Measurement temperature: 40 ° C
Column: Shodex KF-806L (1) + Shodex KF-801 (1), Showa Denko KK detector: YDR-880 (manufactured by SHIMAMURA)

[Production Example 1]
A material having the following composition was dissolved in methyl ethyl ketone (a good solvent for CIR-1085F, which is a near-infrared absorbing dye), a paint was prepared, and a near-infrared absorbing adhesive a was obtained.
-Adhesive resin A 100 parts-Epoxy curing agent (N, N.N ', N'-tetraglycidyl-m-xylylenediamine) 0.05 parts-Near-infrared absorbing dye (Nippon Carlit Co., Ltd., product name: CIR-1085F ) 2.5 parts ・ Silane coupling agent of the following formula (4) (number average molecular weight (Mn) is 1230, weight average molecular weight (Mw) is 12300) 0.007 parts It was coated on Toray Film Co., Ltd., BX8A). The thickness at the time of coating was adjusted so that the thickness of the adhesive after drying was 25 μm. Subsequently, it was dried in an oven at 80 ° C. for 2 minutes. A primary release PET (BKE (RX), manufactured by Toray Film Processing Co., Ltd.) is bonded to the layer comprising this near-infrared absorbing adhesive a and cured at 40 ° C. for 3 days to obtain a near-infrared absorbing adhesive film (adhesive optical film) a1. Got.

（ＣＨ_２−Ｏ）のｎは２０〜２４の整数

_(CH 2 -O) n in 20-24 integer

[Example 1]
A near-infrared absorbing pressure-sensitive adhesive b and a near-infrared absorbing pressure-sensitive adhesive film b1 were obtained in the same manner as described above except that the coating material described in Production Example 1 contained a material having the following composition.
・ Visible light absorbing dye 1 (Arimoto Chemical Co., Ltd., trade name: oil Blue5511) 0.1036 parts ・ Neon emission absorbing dye (Yamamoto Kasei Co., Ltd., trade name: PD-320) 0.109 parts ・ Antioxidant (manufactured by Soken Chemical Co., Ltd.) Name: Additive M) 0.6 parts, UV absorber (product name: TINUVIN109, manufactured by Ciba Specialty Chemicals) 4.5 parts

[Example 2]
A near-infrared-absorbing pressure-sensitive adhesive c and a near-infrared-absorbing pressure-sensitive adhesive film c1 were obtained in the same manner as described above except that the coating material described in Production Example 1 contained a material having the following composition.
・ Visible light absorbing dye 1 (Arimoto Chemical Co., Ltd., trade name: oil Blue5511) 0.1036 parts ・ Visible light absorbing dye 2 (Arimoto Chemical Co., Ltd., trade name: Plast Violet 8855) 0.1345 parts ・ Antioxidant (Soken Chemicals) Product name: Additive M) 0.6 parts, UV absorber (Ciba Specialty Chemicals product name: TINUVIN109) 4.5 parts

[Example 3]
A near-infrared absorbing pressure-sensitive adhesive d and a near-infrared absorbing pressure-sensitive adhesive film d1 were obtained in the same manner as described above except that the coating material described in Production Example 1 contained a material having the following composition.
・ Visible light absorbing dye 2 (trade name: Plast Violet 8855 made by Arimoto Chemical Co., Ltd.) 0.1345 parts ・ Antioxidant (trade name: Additive M made by Soken Chemical Co., Ltd.) 0.6 parts ・ UV absorber (made by Ciba Specialty Chemicals) Product name: TINUVIN109) 4.5 parts

[Example 4]
A near-infrared-absorbing pressure-sensitive adhesive e and a near-infrared-absorbing pressure-sensitive adhesive film e1 were obtained in the same manner as described above except that the coating material described in Production Example 1 contained a material having the following composition.
・ Neon emission absorbing dye (Yamamoto Kasei Co., Ltd., trade name: PD-320) 0.109 parts ・ Antioxidant (Soken Chemicals, trade name: Additive M) 0.6 parts ・ Ultraviolet absorber (Ciba Specialty Chemicals, Inc.) : TINUVIN109) 4.5 parts

[Example 5]
A near-infrared-absorbing pressure-sensitive adhesive f and a near-infrared-absorbing pressure-sensitive adhesive film f1 were obtained in the same manner as described above except that the coating material described in Production Example 1 contained a material having the following composition.
・ Visible light absorbing dye 1 (Arimoto Chemical Co., Ltd., trade name: oil Blue5511) 0.1036 parts ・ Visible light absorbing dye 2 (Arimoto Chemical Co., Ltd., trade name: Plast Violet 8855) 0.1345 parts ・ Neon emission absorbing dye (Yamamoto Kasei) Product name: PD-320) 0.109 parts ・ Antioxidant (product name: Additive M, manufactured by Soken Chemical Co., Ltd.) 0.6 parts ・ UV absorber (product name: TINUVIN109, manufactured by Ciba Specialty Chemicals) 4.5 parts

[Example 6]
A near-infrared absorbing adhesive g and a near-infrared absorbing adhesive film G1 were obtained in the same manner as in Example 5 except that the amount of the silane coupling agent added to the paint was 0.013 part.

[Comparative Example 1]
A near-infrared absorbing adhesive B and a near-infrared absorbing adhesive film B1 were obtained in the same manner as in Example 1 except that no silane coupling agent was added to the paint.

[Comparative Example 2]
A near-infrared absorbing adhesive C and a near-infrared absorbing adhesive film C1 were obtained in the same manner as in Example 2 except that the silane coupling agent was not added to the paint.

[Comparative Example 3]
A near-infrared absorbing adhesive D and a near-infrared absorbing adhesive film D1 were obtained in the same manner as in Example 3 except that no silane coupling agent was added to the paint.

[Comparative Example 4]
A near-infrared absorbing adhesive E and a near-infrared absorbing adhesive film E1 were obtained in the same manner as in Example 4 except that no silane coupling agent was added to the paint.

[Comparative Example 5]
A near-infrared absorbing adhesive F and a near-infrared absorbing adhesive film F1 were obtained in the same manner as in Example 5 except that the silane coupling agent was not added to the paint.

[Comparative Example 6]
A near-infrared absorbing adhesive G and a near-infrared absorbing adhesive film G1 were obtained in the same manner as in Example 6 except that the amount of the silane coupling agent added to the paint was 0.001 part.

The obtained specimen was measured for transmittance (initial absorption spectrum) with a spectrophotometer (Shimadzu Corporation UV3150, JIS Z 8722), and the aggregate diameter of the dye was measured with an optical microscope (500 times). The results are shown in Table 1. The aggregation diameter and number of dyes are values measured in a 400 μm square. The initial absorption spectrum showed results at four points of 800 nm, 850 nm, 900 nm, and 950 nm (Table 1).

  In all of the silane coupling agents (Examples 1 to 6), the aggregate diameter of the dye aggregate is 100 μm or less, the transmittance in the near infrared (NIR) region is low, and a good initial absorption spectrum is shown. . On the other hand, when no silane coupling agent was added (Comparative Examples 1 to 6), the aggregate diameters of the dye aggregates all included those exceeding 100 μm, and further colored pigments (visible light absorbing dyes, neon light emitting absorbing dyes). ) And the like increase the transmittance in the near-infrared region, indicating that the initial absorption spectrum is worse than in the examples.

  Further, as shown in Comparative Example 6, the addition of 0.001 part of the silane coupling agent could not suppress the increase in transmittance in the near infrared region, and contained a dye aggregate having an aggregate diameter exceeding 100 μm. .

As described above, according to the present invention, by adding a coloring dye or the like, by adding an appropriate amount of a silane coupling agent, the transmittance in the near infrared region where the aggregate diameter of the dye aggregate increases and increases. The aggregate diameter of the dye aggregate was suppressed to 100 μm, and good transmittance in the near infrared region could be kept low. That is, even when other dyes (near-infrared absorbing dyes other than diimonium dyes, visible light absorbing dyes, neon luminescent absorbing dyes, etc.) were added, the initial absorption spectrum of the diimonium dye contained in the adhesive layer became preferable. Accordingly, it is possible to provide a near-infrared absorbing adhesive sheet (adhesive optical film) that can be used for various chromaticity adjustments and a plasma display panel using the same.

Claims (12)

An acrylic polymer, a diimonium dye, a dye other than the diimonium dye, a near-infrared absorbing adhesive layer containing a silane coupling agent represented by the following formula (4), and a base material layer,
A pressure-sensitive adhesive optical film, wherein a dye aggregate having an aggregate diameter of 100 μm or less is present in the near-infrared absorbing pressure-sensitive adhesive layer.

(In the formula, n is an integer of 20 to 24.)   2. The pressure-sensitive adhesive optical film according to claim 1, wherein in the near-infrared absorbing pressure-sensitive adhesive layer, the number of dye aggregates having a diameter of more than 100 μm contained in 400 μm square is 3 or less.   2. The pressure-sensitive adhesive optical film according to claim 1, wherein the other dye is at least one selected from near-infrared absorbing dyes, visible light absorbing dyes, and neon luminescent absorbing dyes other than the diimonium dye. The pressure-sensitive adhesive optical film according to claim 1 , wherein the silane coupling agent has a number average molecular weight (Mn) of 500 or more. The pressure-sensitive adhesive optical film according to claim 1 or 4 , wherein the silane coupling agent has a weight average molecular weight (Mw) of 5000 or more. 2. The pressure-sensitive adhesive optical film according to claim 1 , wherein Mw / Mn, which is a ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn), of the silane coupling agent is 3 or more and 15 or less. The pressure-sensitive adhesive optical film according to claim 1 , wherein the silane coupling agent is contained in an amount of 0.002 parts by mass or more and less than 0.2 parts by mass with respect to 100 parts by mass of the acrylic polymer. The pressure-sensitive adhesive optical film according to any one of claims 1 to 7 , wherein the acrylic polymer has an acid value of 7 to 50 mgKOH / g. The near-infrared absorbing adhesive layer is one or two or more crosslinking agents selected from the group consisting of epoxy crosslinking agents, isocyanate crosslinking agents, amine crosslinking agents, imine crosslinking agents, and peroxide crosslinking agents. characterized in that it contains a combination of pressure-sensitive adhesive optical film of any one of claims 1-8. The pressure-sensitive adhesive optical film according to any one of claims 1 to 9 , wherein the near-infrared absorbing pressure-sensitive adhesive layer contains a rust inhibitor. Wherein the metal mesh film is being adhered to the near infrared absorbing adhesive layer, pressure-sensitive adhesive optical film of any one of claims 1-10. The pressure-sensitive adhesive optical film of any one of claims 1 to 11 is adhered to the surface, the plasma display panel.

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