JP2013216726A - Optical pressure-sensitive adhesive composition and optical functional film using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical pressure-sensitive adhesive composition capable of improving both durability and reworkability that are conflicting when used in attaching an optical functional film to a glass substrate.SOLUTION: An optical pressure-sensitive adhesive composition is obtained by mixing 100 pts.mass of a (meth)acrylate-based copolymer (a) with 0.001-5.0 pts.mass of an organopolysiloxane (b) and/or its hydrolytic condensate. The organopolysiloxane (b) is a compound containing an alkoxy group, an acid anhydride group and a polyether group in a molecule, in which two or more kinds of specific siloxane units that form a siloxane bond are inserted between atoms of O and Si in at least one of O-Si bonds existing in a molecule of an alkoxysilane represented by the formula: [RSi(OR)] or its hydrolytic condensate. An optical functional film is obtained by lamination of a film composed of the composition.

Description

  The present invention relates to an optical pressure-sensitive adhesive composition and an optical functional film. More specifically, the present invention relates to an optical pressure-sensitive adhesive composition that is optimal for an optical functional film in a liquid crystal display device, and an optical functional film using the composition.

  A liquid crystal cell constituting a liquid crystal display device is a pressure-sensitive adhesive layer (film) formed by sandwiching a liquid crystal component oriented in a predetermined direction between two glass substrates and forming an optical pressure-sensitive adhesive composition outside these glass substrates. An optical functional film such as a polarizing plate or a laminate of a polarizing plate and a retardation plate (hereinafter, these may be simply referred to as “optical functional film”) is attached. 2. Description of the Related Art In recent years, liquid crystal cells have been used to significantly reduce weight and thickness, so that liquid crystal display devices are widely used as displays for vehicles, outdoor instruments, and displays such as personal computers and televisions. As a result, the demand tends to increase. Along with the spread of this application, the environment in which liquid crystal display devices are used varies widely, so it may be very harsh, and the adhesive composition used to manufacture liquid crystal display devices can also handle harsh environments. Performance is required. Specifically, even when exposed to high temperature or high temperature and high humidity conditions, the pressure-sensitive adhesive layer formed by the pressure-sensitive adhesive composition does not foam or the attached optical functional film does not peel off from the substrate. (Hereinafter, a characteristic satisfying these is called “durability”).

  On the other hand, in order to solve the above problems, Patent Document 1 proposes a pressure-sensitive adhesive composition in which a specific amount of a specific polymer type silane coupling agent is contained in an acrylic polymer. Patent Document 2 proposes a pressure-sensitive adhesive composition in which a specific amount of a specific silane compound monomer is contained in an acrylic polymer.

Japanese Patent No. 3498158 Japanese Patent No. 3533446

  However, according to the study by the present inventors, the pressure-sensitive adhesive composition described in Patent Document 1 is not compatible with the acrylic polymer because the silane coupling agent used is not sufficient. Separation occurs, and it cannot be said that the durability is sufficient for high performance requirements. In addition, the pressure-sensitive adhesive composition described in Patent Document 2 is not sufficiently maintained over time because the silane compound monomer is liberated over time. As described above, any of the above-described techniques has sufficient durability that can be satisfied even when the liquid crystal display device is used in an extremely harsh environment, which is required for an optical pressure-sensitive adhesive composition in recent years. It was not meant to be shown.

  In addition to this, there are the following problems specific to the optical pressure-sensitive adhesive composition. In the current manufacturing process of liquid crystal display devices, if a problem occurs when an optical functional film is bonded, liquid crystal cells and liquid crystal materials are very expensive. The exfoliating film is peeled off and reattached. However, many of the conventional acrylic resin-based adhesives used in the adhesive layer of optical functional films have high adhesive strength, which can damage the glass substrate during peeling. In many cases, the gap width between the two glass substrates filled with the liquid crystal component is changed, and the liquid crystal cell and the liquid crystal material after peeling cannot be used again to manufacture the liquid crystal display device. Moreover, even if the optical functional film can be peeled without damaging the liquid crystal cell or the liquid crystal material, a part of the adhesive remains on the glass substrate or the like, and the work of reattaching the optical functional film cannot be performed. There was also a problem.

  For this reason, as a characteristic required for the pressure-sensitive adhesive composition used for sticking the optical functional film, in addition to the above-described high durability and its maintenance, the optical function becomes a contradictory characteristic. After sticking the adhesive film, the film can be easily peeled even after a long time, and the adhesive does not remain on the glass substrate even after peeling (hereinafter, these are satisfied) Is called “reworkability”).

  Accordingly, an object of the present invention is a pressure-sensitive adhesive composition for use in sticking an optical functional film on a substrate such as glass of a liquid crystal display device, which has opposite characteristics, “durability” and “reworkability”. And an optical pressure-sensitive adhesive composition excellent in both, and an optical functional film having a pressure-sensitive adhesive layer formed from the composition.

  The inventors of the present invention have made extensive studies to solve the above-described problems of the prior art, and have found that the above-described problems can be solved by the following present invention. That is, in the present invention, 0.001 to 5.0 parts by mass of organopolysiloxane (b) and / or its hydrolysis with respect to 100 parts by mass of the copolymer (a) containing (meth) acrylic acid ester. A condensate is added and blended, and the organopolysiloxane (b) is an alkoxysilane represented by the following formula [1] or at least one O-Si bond existing in the molecule of the partially hydrolyzed condensate thereof. In which at least two types of siloxane units are inserted between O and Si atoms to form a siloxane bond, and the compound has an alkoxy group, an acid anhydride group, and a polyether group in the molecule. And the inserted siloxane unit is 1 to 100 siloxane units represented by the following formula [2], the formula [2], and 1 to 100 siloxane units represented by the formula [2], Represented And siloxane units that provides an optical pressure-sensitive adhesive composition, characterized in that between 0 and 100 or below [2] siloxane units represented by C-type expressions that are inserted if necessary.

（［２］式中、Ｘは、酸無水物基を有する一価炭化水素基を示す。Ｙは、ポリエーテル基を有する一価炭化水素を有する基を示す。Ｒ³は、それぞれ独立に、水素原子、又はハロゲン原子で置換されてもよい炭素原子数１〜２０の一価炭化水素基を示す。） [1] Formula R ¹ _n Si (OR ² ) _4-n
(In the formula [1], R ¹ represents a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom. R ² represents an alkyl group having 1 to 10 carbon atoms. n represents 0 or 1.)

([2] In the formula, X represents a monovalent hydrocarbon group having an acid anhydride group. Y represents a group having a monovalent hydrocarbon having a polyether group. R ³ is independently A hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom.)

（［３］式中、Ａは、直鎖状又は分岐鎖状の炭素数２〜６のアルキレン基を示す。）
［４］式
−Ｃ_mＨ_2m−Ｏ(Ｃ₂Ｈ₄Ｏ)_p(Ｃ₃Ｈ₆Ｏ)_qＲ⁴
（［４］式中、Ｒ⁴は、水素原子、炭素原子数１〜６の一価の炭化水素基又は下記［５］式で表される基のいずれかを示す。ｍは１以上の整数を示す。ｐ、ｑは、０以上の整数を示す。ただし、ｐ、ｑのうち少なくとも１つは、１以上の整数をとる。）

（［５］式中、Ｒ⁵は、炭素原子数１〜４の一価の炭化水素基を示す。） The following are mentioned as a preferable form of this invention.
As the organosiloxane (b), in the formula [2], X in the formula A is a monovalent hydrocarbon group having an acid anhydride group represented by the following formula [3], and Y in the formula B However, it is preferable that at least the polyorganosiloxane (b) into which a siloxane unit is inserted, which is a monovalent hydrocarbon group having a polyether group represented by the following formula [4], is blended.

([3] In the formula, A represents a linear or branched alkylene group having 2 to 6 carbon atoms.)
[4] formula _{-C m H 2m -O (C 2} H 4 O) p (C 3 H 6 O) q R 4
(In the formula [4], R ⁴ represents any one of a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following formula [5]. M is an integer of 1 or more. P and q represent an integer of 0 or more, provided that at least one of p and q is an integer of 1 or more.)

(In the formula [5], R ⁵ represents a monovalent hydrocarbon group having 1 to 4 carbon atoms.)

  In the above formula [4], p is 0 and q is an integer of 1 or more. That is, in the formula [2], Y in the formula B has a propylene oxide type polyether group. A valent hydrocarbon group is preferred. Further, it is more preferable that at least the organosiloxane (b) in which the siloxane unit represented by the formula C in the formula [2] is not inserted is blended.

Moreover, it is preferable that the optical pressure-sensitive adhesive composition of the present invention has the following configuration.
The copolymer (a) containing the (meth) acrylic acid ester is a copolymer having at least an alkyl (meth) acrylate monomer having an organic substituent having 1 to 18 carbon atoms in the side chain as a forming component. And the weight average molecular weight of this copolymer is 400,000-2 million.

  Further, 0.01 to 40 parts by mass of a crosslinking agent (e) is added to 100 parts by mass of the copolymer (a) containing the (meth) acrylic acid ester. e) is at least one selected from the group consisting of an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, a metal-based crosslinking agent, and an aziridine-based crosslinking agent.

  A silane coupling agent (f) other than the organopolysiloxane (b) and / or a hydrolysis condensate thereof is further added, and further, the silane coupling agent (f) and / or a hydrolysis condensation thereof. It is that the addition amount of a thing is 0.01-5 mass parts with respect to 100 mass parts of copolymers (a) containing the said (meth) acrylic acid ester.

  Moreover, this invention provides the optical functional film characterized by laminating | stacking the film | membrane which consists of one of the said optical adhesive compositions on the single side | surface or both surfaces as another embodiment.

  According to the present invention, a high level of realization has been demanded in recent years for the pressure-sensitive adhesive composition used for laminating and sticking an optical functional film on a substrate such as glass of a liquid crystal display device. It is possible to provide an optical pressure-sensitive adhesive composition excellent in durability and reworkability, which are contradictory properties. In addition, according to the present invention, the pressure-sensitive adhesive layer formed by the above-described excellent pressure-sensitive adhesive composition can achieve durability that can withstand use in harsh environments, and also has excellent reworkability. It becomes possible to provide a protective film.

Next, the present invention will be described in detail with reference to the best mode for carrying out the invention.
The pressure-sensitive adhesive composition of the present invention comprises a copolymer (a) containing a (meth) acrylic acid ester, an organopolysiloxane (b) having a specific structure and / or a hydrolysis condensate thereof (hereinafter simply referred to as an organopolyester). (Referred to as siloxane (b)). Since the pressure-sensitive adhesive composition of the present invention contains a specific organopolysiloxane (b), the formed pressure-sensitive adhesive layer has improved durability and exhibits excellent reworkability. Become. Hereinafter, each component will be described. The term “(meth) acryl” in the claims and the specification of the present invention means both “acryl” and “methacryl”, and the term “(meth) acrylate” "And" methacrylate ".

[Organopolysiloxane (b)]
The organopolysiloxane (b) that characterizes the present invention will be described.
The organopolysiloxane (b) is an alkoxysilane represented by the following formula [1] or at least one O-Si bond existing in the molecule of the partial hydrolysis-condensation product, and between the O and Si atoms: At least two types of siloxane units are inserted in a siloxane bond and are compounds having an alkoxy group, an acid anhydride group, and a polyether group in the molecule. The inserted siloxane units constituting the compound are 1 to 100 siloxane units represented by the following formula [2] formula A and 1 to 100 following formula [2] formula B And 0 to 100 siloxane units represented by the following formula [2], which are inserted as necessary. In the organopolysiloxane (b) that characterizes the present invention, it is required that at least two types of siloxane units selected from these are inserted, and these siloxane units are located between one O and Si atom, One or a plurality of them may be inserted, or they may be inserted individually or together with other siloxane units.

[1] Formula R ¹ _n Si (OR ² ) _4-n
(In the formula [1], R ¹ represents a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom. R ² represents an alkyl group having 1 to 10 carbon atoms. n represents 0 or 1.)

（［２］式中、Ｘは、酸無水物基を有する一価炭化水素基を示す。Ｙは、ポリエーテル基を有する一価炭化水素する基を示す。Ｒ³は、それぞれ独立に、水素原子、又はハロゲン原子で置換されてもよい炭素原子数１〜２０の一価炭化水素基を示す。）

(In the formula [2], X represents a monovalent hydrocarbon group having an acid anhydride group. Y represents a monovalent hydrocarbon group having a polyether group. R ³ is independently hydrogen. A monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with an atom or a halogen atom.)

  Examples of the alkoxysilane represented by the above formula [1] include the following, but the present invention is not limited thereto. For example, tetramethoxysilane, methyltrimethoxysilane, toteraethoxysilane, and methyltriethoxysilane can be used. In the present invention, partial hydrolysis condensates of these alkoxysilanes alone or in combination can be used. . The “partially hydrolyzed condensate” refers to a condensate partially hydrolyzed by combining one or more of the above alkoxysilanes.

  As described above, the organopolysiloxane (b) that characterizes the present invention contains 2 or 2 O-Si bonds existing in the molecule of the alkoxysilane or partially hydrolyzed condensate thereof as described above. More than one type of specific siloxane units are inserted to form siloxane bonds. With regard to “a specific siloxane unit is inserted between O and Si atoms to form a siloxane bond” defined in the present invention, the partial hydrolysis of tetramethoxysilane represented by the following formula [6] The decomposition condensate (linear methoxysiloxane: tetramer) will be specifically described. Hereinafter, the condensate is simply referred to as a compound of the formula [6].

[6] In the molecule of the compound represented by the formula, as shown above, there are 16 O—Si bonds in total, α ^{1 to} α ⁸ and β ^{1 to} β ⁸ . In the organopolysiloxane (b) used in the present invention, at least one of these O-Si bonds, two kinds of specific siloxane units defined in the present invention form a siloxane bond between O and Si atoms. It is characterized by being inserted. For example, when two siloxane units A and one siloxane unit B shown below are co-inserted into the O-Si bond at the β ⁴ site present in the molecule of the compound of the above formula [6] Has a structure represented by the following formula [7].

（上記Ａ或いはＢの式中、Ｘは、酸無水物基を有する一価炭化水素基を示す。Ｙは、ポリエーテル基を有する一価炭化水素基を示す。）

(In the above formula A or B, X represents a monovalent hydrocarbon group having an acid anhydride group. Y represents a monovalent hydrocarbon group having a polyether group.)

Next, as another example, “the specific siloxane unit is inserted between O and Si atoms by forming a siloxane bond” as defined in the present invention is expressed by the following formula [8]. Specific description will be given using a partially hydrolyzed condensate of tetramethoxysilane (branched methoxysiloxane: hexamer). Hereinafter, the condensate is simply referred to as a compound of the formula [8].

[8] In the molecule of the compound of the formula, as shown above, there are a total of 20 O—Si bonds, α ^{1 to} α ⁸ and β ^{1 to} β ¹² . For example, two siloxane units A and two siloxane units B shown above are bonded to the O-Si bond at the β ¹ , β ⁶ , and β ¹² sites present in the molecule of the compound of the above [8]. When inserted, the structure is as shown in the following formula [9].

  The organopolysiloxane (b) used in the present invention is not limited to the above, and at any position of the O—Si bond existing in the molecule of the compound of the formulas [6] and [8] exemplified above, Siloxane units A and B may be inserted. However, as shown in the formulas [7] and [9], the inserted siloxane unit needs to be inserted by forming a siloxane bond between the O and Si atoms in the O-Si bond. . This means that the insertion of the specific siloxane unit defined in the present invention does not cause a bond such as Si—Si or O—O in the molecule.

  The organopolysiloxane (b) that characterizes the present invention will be described in more detail. As described above, the organopolysiloxane (b) is based on the alkoxysilane represented by the above formula [1] or a partially hydrolyzed condensate thereof, and contains at least one O-Si bond existing in the molecule. In addition, a siloxane unit having an acid anhydride group (a siloxane unit represented by the formula A in the above formula [2]) and a siloxane unit having a polyether group (the formula [2] above) between O and Si atoms. Among them, at least two types of siloxane units represented by the formula B have a structure in which a siloxane bond is formed. Further, as is clear from the above formula [1], the organopolysiloxane (b) has an alkoxy group in its structure. When the pressure-sensitive adhesive layer is formed with the optical pressure-sensitive adhesive composition of the present invention, this alkoxy group is a main component of the pressure-sensitive adhesive composition described later by reacting with a substrate such as glass constituting a liquid crystal cell or the like. A bond between the copolymer (a) containing the (meth) acrylic acid ester (hereinafter sometimes referred to as an acrylic copolymer (a)) and the substrate is formed. The present inventors believe that this is one of the reasons why the pressure-sensitive adhesive composition of the present invention can achieve a high level of “durability” that cannot be achieved by the prior art. Examples of preferable alkoxy groups in the structure include a methoxy group, an ethoxy group, and a propoxy group, and at least one selected from these groups can be used.

The organopolysiloxane (b) used in the present invention has a specific siloxane unit defined in the present invention inserted between the O and Si atoms as described above. become those having a hydrocarbon group R ³ monovalent having from 1 to 20 carbon atoms. The optical pressure-sensitive adhesive composition of the present invention is a material in which such a monovalent hydrocarbon group is introduced into the siloxane skeleton, so that the added organopolysiloxane (b) and the acrylic that is the main component of the pressure-sensitive adhesive are used. Compatibility with the system copolymer (a) can be improved, and phase separation or the like can hardly occur. The following are mentioned as an example of a C1-C10 monovalent hydrocarbon group which can be used conveniently by this invention. For example, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, octyl group, nonyl group, decyl group; Aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group; aralkyl groups such as benzyl group, phenylethyl group, phenylpropyl group; vinyl group, aryl group, propenyl group, isopropenyl group, butenyl group, hexenyl group, Examples thereof include alkenyl groups such as cyclohexenyl group and octenyl group. In addition, those in which a part of hydrogen atoms of these monovalent hydrocarbon groups are substituted include halogen atoms (fluorine atom, chlorine atom, bromine atom, iodine, chloromethyl group, trifluoromethyl group, chloropropyl group, etc.) Examples thereof include monovalent hydrocarbon groups substituted with (atom). A methyl group is preferred.

  The organopolysiloxane (b) characterizing the present invention has a monovalent hydrocarbon group X having an acid anhydride group in its structure. And, this acid anhydride group part is a carboxyl group and / or hydroxyl group of the acrylic copolymer (a) which is the main component of the pressure-sensitive adhesive, and further a crosslinking agent (e) added as necessary. Therefore, the (meth) acrylic acid ester copolymer (a) and the organopolysiloxane (b) are integrated.

（［３］式中、Ａは、直鎖状又は分岐鎖状の炭素数２〜６のアルキレン基を示す。） Preferable examples of the monovalent hydrocarbon group X having an acid anhydride group (hereinafter sometimes abbreviated as the monovalent hydrocarbon group X) include, for example, a group represented by the following formula [3]. It is done.

([3] In the formula, A represents a linear or branched alkylene group having 2 to 6 carbon atoms.)

  The organopolysiloxane (b) characterizing the present invention may be abbreviated as a monovalent hydrocarbon group Y having a polyether group in addition to the monovalent hydrocarbon group X (hereinafter, abbreviated as a monovalent hydrocarbon group Y). )have. Thus, by having a polyether group in the structure, the reaction between the alkoxy group in the molecule and the substrate described above is suppressed, and the bond between the acrylic copolymer (a) and the substrate is suppressed. It can be reduced moderately. Thereby, the high level rework property required when it is set as an adhesive layer can be provided to the optical adhesive composition of this invention. As monovalent hydrocarbon group Y, the structure represented by following [4] Formula can be illustrated.

（［５］式中、Ｒ⁵は、炭素原子数１〜４の一価の炭化水素基を示す。） [4] formula _{-C m H 2m -O (C 2} H 4 O) p (C 3 H 6 O) q R 4
(In the formula [4], R ⁴ represents any one of a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following formula [5]. M is an integer of 1 or more. P and q represent an integer of 0 or more, provided that at least one of p and q is an integer of 1 or more.)

(In the formula [5], R ⁵ represents a monovalent hydrocarbon group having 1 to 4 carbon atoms.)

  In said [4] Formula, it is preferable that p and q take an integer of 0-50, respectively. Accordingly, the polyether group may be any of an ethylene oxide type (hereinafter referred to as EO type), a propylene oxide type (hereinafter referred to as PO type), or an ethylene oxide-propylene oxide type (hereinafter referred to as EO-PO type). But you can. In the case of the EO-PO type, the arrangement may be random, block, or alternating. Among the above, it is preferable to use PO type. That is, the introduction of a group having a PO-type polyether into the structure of the organopolysiloxane (b) improves the heat and moisture resistance of the optical pressure-sensitive adhesive composition of the present invention. The PO-type polyether has relatively good compatibility with the acrylic copolymer (a) which is the main component of the pressure-sensitive adhesive. In this case, the formula [2] defined in the present invention is not necessarily used. It is not necessary to introduce the siloxane unit represented by the formula C in FIG. In addition, the insertion of the siloxane unit represented by the formula C in the formula [2] may cause adverse effects such as deterioration of reworkability.

  The compounding quantity of the above-mentioned organopolysiloxane (b) in the adhesive composition of this invention is 0.001-5.0 mass parts with respect to 100 mass parts of acrylic copolymers (a) mentioned later. When the amount added is less than 0.001 part by mass, the adhesive strength of the acrylic copolymer (a) cannot be reduced appropriately, and reworkability is achieved as compared with the case where it is within the above range. Is inferior. On the other hand, when the addition amount exceeds 5.0 parts by mass, the adhesive strength of the (meth) acrylic acid ester copolymer (a) can be reduced, but compared with the case where it is within the above range, The durability is inferior.

  The organopolysiloxane (b) that characterizes the present invention changes over time when an active hydrogen-containing compound having reactivity with an acid anhydride group or alkoxysilyl group in its structure, such as water or alcohol, is mixed. In some cases, the purity may decrease. As a mechanism of the change with time, for example, by the moisture present as moisture in the air, the alkoxysilyl group in the organopolysiloxane is first hydrolyzed and alcohol is generated as the first step. Next, as a second step, the generated alcohol causes a ring-opening reaction of an acid anhydride ring to generate a carboxylic acid. In the third stage, methanol is generated again by the transesterification reaction between the produced carboxylic acid and the alkoxysilyl group. Thereafter, the second stage and the third stage proceed repeatedly, and the purity decreases with time.

  In order to suppress such a change with time of the organopolysiloxane (b), it is effective to use an active hydrogen-containing compound scavenger in the pressure-sensitive adhesive composition of the present invention. The scavenger refers to a substance that reacts with the active hydrogen-containing compound to extinguish the active hydrogen in the active hydrogen-containing compound. Examples of the scavenger for the active hydrogen-containing compound include the following, but the active hydrogen-containing compound can be used without being limited thereto as long as it is within the scope of the effect of the present invention. Preferably, an α-silyl aliphatic ester compound is used. The α-silyl aliphatic ester compound refers to an ester of an aliphatic carboxylic acid in which a silyl group is directly bonded to the α-position carbon atom.

  Specific examples of the α-silyl aliphatic ester compound include, for example, methyl α-trimethoxysilylpropionate, ethyl α-trimethoxysilylpropionate, propyl α-trimethoxysilylpropionate, and butyl α-trimethoxysilylpropionate. , Α-trimethoxysilylpropionate pentyl, α-trimethoxysilylpropionate hexyl, α-trimethoxysilylpropionate octyl, α-trimethoxysilylpropionate decyl, α-trimethoxysilylpropionate cyclohexyl, α-trimethoxy Isopropyl silylpropionate, phenyl α-trimethoxysilylpropionate, methyl α-triethoxysilylpropionate, ethyl α-triethoxysilylpropionate, α-triethoxysilylpropionate propyl, α-to Butyl ethoxysilylpropionate, pentyl α-triethoxysilylpropionate, hexyl α-triethoxysilylpropionate, octyl α-triethoxysilylpropionate, decyl α-triethoxysilylpropionate, cyclohexyl α-triethoxysilylpropionate , Α-triethoxysilylpropionate isopropyl, α-triethoxysilylpropionate phenyl, α-methyldimethoxysilylpropionate methyl, α-methyldimethoxysilylpropionate ethyl, α-methyldimethoxysilylpropionate propyl, α-methyldimethoxy Butyl silylpropionate, pentyl α-methyldimethoxysilylpropionate, hexyl α-methyldimethoxysilylpropionate, octyl α-methyldimethoxysilylpropionate Le, such as α- methyldimethoxysilyl propionic acid decyl. Among these, ethyl α-trimethoxysilylpropionate and octyl α-methyldimethoxysilylpropionate are more preferable because of high capture reactivity and availability of materials.

  When such an α-silyl aliphatic ester compound reacts with an active hydrogen-containing compound, the silyl group is separated from the α-position carbon atom, and an active silicon-free organosilicon compound and an active hydrogen-free aliphatic carboxyl An acid ester is formed. Since any product does not contain active hydrogen, the organosilicon compound containing an acid anhydride residue and a hydrolyzable silyl group (alkoxysilyl group) has no reactivity. Therefore, the organosiloxane (b) is kept in a high purity state without changing with time. As a specific example, a case where the active hydrogen-containing compound mixed in the organopolysiloxane (b) is methanol and the scavenger for the active hydrogen-containing compound is ethyl α-trimethoxysilylpropionate will be described. In this case, the compounds produced by the capture reaction are tetramethoxysilane and ethyl propionate, but both products are reactive with organosilicon compounds containing acid anhydride groups and hydrolyzable silyl groups. No. As a result, the purity of the organopolysiloxane (b) is maintained without being affected by methanol even if methanol is mixed.

  The organopolysiloxane (b) described above may be contained as it is in the optical pressure-sensitive adhesive composition of the present invention, but can also be contained in the form of a hydrolysis condensate.

[Copolymer containing (meth) acrylic acid ester (a)]
Hereinafter, the acrylic copolymer (a) which is the main component of the optical pressure-sensitive adhesive composition of the present invention used together with the above-described organopolysiloxane (b) will be described.
As a suitable thing of the acryl-type copolymer (a) which comprises this invention, it becomes an alkyl (meth) acrylate monomer which has a C1-C18 organic substituent in a side chain at least as a formation component, for example. Examples of the copolymer include those having adhesiveness and having a weight average molecular weight of 400,000 to 2,000,000. When the weight average molecular weight is less than 400,000, the cohesive force of the formed pressure-sensitive adhesive layer is weak even when a cross-linking agent (e) described later is used, and the pressure-sensitive adhesive layer is easily foamed or peeled off. Is not preferable because it may become insufficient. On the other hand, when the weight average molecular weight exceeds 2,000,000, the viscosity of the pressure-sensitive adhesive composition becomes too high and the workability may be inferior.

  As a monomer used for the synthesis of the acrylic copolymer (a) constituting the present invention, in addition to a conventionally known monomer capable of forming a (meth) acrylic acid ester, the aforementioned organopolysiloxane (b ) Having a monovalent hydrocarbon group X having an acid anhydride group contained in the structure and / or an organic group capable of reacting with an organic substance such as a crosslinking agent (e) and / or an optical functional film described later. Monomers may be included. That is, the acrylic copolymer (a) constituting the pressure-sensitive adhesive composition of the present invention is a (meth) acrylate monomer, a (meth) acrylate monomer having a substituent such as a carboxy group or a hydroxyl group, these It can synthesize | combine by using at least 2 or more types of monomers chosen from the other monomer containing the reactive unsaturated double bond copolymerizable with this monomer.

Specific examples of the monomer that can be used for the synthesis of the acrylic copolymer (a) constituting the present invention include the following.
For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, isooctyl ( Alkyl (meth) acrylate monomers such as (meth) acrylate, isononyl (meth) acrylate, lauryl (meth) acrylate;
Aromatic group-containing (meth) acrylate monomers such as phenoxyethyl (meth) acrylate and benzyl (meth) acrylate;
Carboxy group-containing (meth) acrylate monomers such as (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid or carboxyethyl (meth) acrylate;
Acid anhydride monomers such as maleic anhydride or fumaric anhydride, amide group-containing monomers such as (meth) acrylamide N- (2-hydroxyethyl) (meth) acrylamide;
2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, caprolactone-modified (meth) acrylate, polyethylene glycol mono (meth) acrylate Or hydroxyl group-containing (meth) acrylate monomers such as polypropylene glycol mono (meth) acrylate, amino group-containing (meth) acrylate monomers such as dimethylaminoethyl (meth) acrylate;
Aromatic ring-containing monomers such as styrene methyl styrene;
Examples thereof include vinyl acetate and (meth) acrylonitrile.

  The acrylic copolymer (a) formed from the monomers as listed above is not particularly limited in the arrangement rule of the monomers, and may be any of random copolymers, block copolymers and others. .

  The acrylic copolymer (a) obtained by copolymerizing each monomer as listed above can be produced by ordinary solution polymerization, bulk polymerization, emulsion polymerization, suspension polymerization, etc. The copolymer is preferably produced by solution polymerization obtained as a solution. That is, when the acrylic copolymer (a) is obtained as a solution, it can be used as it is for producing the pressure-sensitive adhesive composition of the present invention. Examples of the solvent used for the solution polymerization include organic solvents such as ethyl acetate, toluene, n-hexane, acetone, and methyl ethyl ketone.

  Examples of the polymerization initiator used in the polymerization include peroxides such as benzoyl peroxide and lauryl peroxide, azobis compounds such as azobisisobutyronitrile and azobisvaleronitrile, and polymer azo polymerization initiators. These can be used alone or in combination. Moreover, in the said superposition | polymerization, in order to adjust the molecular weight of a copolymer, a conventionally well-known chain transfer agent can be used.

[Other ingredients]
(Crosslinking agent (e))
The optical pressure-sensitive adhesive composition of the present invention is an organopolysiloxane (b) described above in the range of 0.001 to 5.0 parts by mass with respect to 100 parts by mass of the acrylic copolymer (a). / Or its hydrolysis-condensation product is added and blended, and 0.01 to 40 parts by mass of a crosslinking agent (e) can be further added. Examples of the crosslinking agent (e) include those selected from the group consisting of an isocyanate crosslinking agent, an epoxy crosslinking agent, a metal crosslinking agent, and an aziridine crosslinking agent. Specifically, for example, a polyglycidyl compound having two or more glycidyl groups in one molecule, a polyisocyanate compound having two or more isocyanate groups in one molecule, and a polyaziridine having two or more aziridinyl groups in one molecule Examples thereof include a compound, a polyoxazoline compound having two or more oxazoline groups in one molecule, a metal chelate compound, or a butylated melamine compound. These can be used alone or in combination of two or more.

  Examples of the polyglycidyl compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, glycerin diglycidyl ether, neopentyl glycol diglycidyl ether, and 1,6-hexane. Diol diglycidyl ether, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, trimethylolpropane polyglycidyl ether, diglycerol poly Polyfunctional glycidyl compounds such as glycidyl ether can be used, and at least one selected from these groups can be used.

  Examples of the polyisocyanate compound include tolylene diisocyanate, xylene diisocyanate, hydrogenated xylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and prepolymers modified from these, and at least one selected from these groups is used. Can be used.

  Examples of the polyaziridine compound include 1,1 ′-(methylene-di-p-phenylene) bis-3,3-aziridylurea, 1,1 ′-(hexamethylene) bis-3,3-aziridylurea, Ethylenebis- (2-aziridinylpropionate), tris (1-aziridinyl) phosphine oxide, 2,4,6-triaziridinyl-1,3,5-triazine, trimethylolpropane-tris- (2-aziridinini) Lupropionate) and the like, and at least one selected from these groups can be used.

  It is preferable that the addition amount of a crosslinking agent (e) is 0.01-40 mass parts with respect to 100 mass parts of acrylic copolymers (a), More preferably, it is 0.02-30 mass parts. is there. When the content is less than 0.01 parts by mass, the cohesive force of the pressure-sensitive adhesive composition becomes low, and the durability may be inferior compared with the above range, which is not preferable. On the other hand, when the amount used exceeds 40 parts by mass, the resulting pressure-sensitive adhesive composition becomes excessive in cohesive strength, which may cause peeling of the optical functional film to be adhered, which is not preferable.

  In addition, radiation (preferably UV) crosslinking is also effective as a crosslinking mode, and in that case, a monomer having at least two reactive double bonds capable of polymerization and a photopolymerization initiator (including a sensitizer) are added. can do. Examples of the monomer having at least two polymerizable double bonds include polyethylene glycol diacrylate, propoxylated ethoxylated bisphenol A diacrylate, tricyclodecane dimethanol diacrylate, and 1,9-nonanediol diacrylate. Multifunctional (meth) acrylates such as bifunctional (meth) acrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, isocyanuric acid triacrylate, tris (2-acryloxyethyl) isocyanurate . If necessary, the crosslinking density can be controlled by using a known monomer having only one polymerizable reactive double bond. As the photopolymerization initiator, known photopolymerization initiators using radiation (ultraviolet rays) can be used. For example, aminoketone series, hydroketone series, acylphosphine oxide series, benzyldimethyl ketal series, benzophenone series, trichloromethyl group-containing And triazine derivatives.

(Silane coupling agent (f))
Further, the optical pressure-sensitive adhesive composition of the present invention can further contain a silane coupling agent (f) other than the organopolysiloxane (b) essential in the present invention and / or a hydrolysis condensate thereof. . By adding the silane coupling agent (f), the durability of the pressure-sensitive adhesive layer formed by the optical pressure-sensitive adhesive composition of the present invention can be further improved. It is preferable that the addition amount of a silane coupling agent (f) and / or its hydrolysis-condensation product is 0.01-5 mass parts with respect to 100 weight part of copolymers (a).

  It does not specifically limit as said silane coupling agent (f), A well-known thing can be used. For example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, epoxy group-containing silane coupling agent such as epoxy group-containing alkoxysilane oligomer, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ- Mercapto group-containing silane coupling agents such as mercaptopropylmethyldiethoxysilane, mercapto group-containing alkoxysilane oligomers, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxy Amino group-containing silane coupling agents such as silane and N-phenyl-γ-aminopropyltrimethoxysilane, and isocyanate group-containing silane coupling agents such as γ-isocyanatopropyltrimethoxysilane and γ-isocyanatopropyltriethoxysilane. , At least one selected from these groups, and / or a hydrolysis-condensation product thereof can be used.

(Other additives)
In addition, the optical pressure-sensitive adhesive composition of the present invention may be blended with various additives within a range that does not impair the effects of the present invention, depending on necessary properties such as the purpose of adjusting the adhesive strength. For example, terpene-based, terpene-phenol-based, coumarone-indene-based, styrene-based, rosin-based, xylene-based, phenol-based or petroleum-based tackifier resins, antioxidants, ultraviolet absorbers, fillers, pigments, etc. can do. The optical pressure-sensitive adhesive composition of the present invention is preferably in the form of a solution containing an organic solvent. In this case, the pressure-sensitive adhesive layer can be easily formed.

[Optical functional film]
Hereinafter, an optical functional film which is another embodiment of the present invention will be described.
The optical functional film of the present invention has “durability” and “reworkability” on one side or both sides of an optical functional film in which an adhesive layer is not formed (hereinafter referred to as “raw film”). Is characterized by being laminated with a film (adhesive layer) made of the optical adhesive composition of the present invention. For this reason, the optical functional film of the present invention does not peel off from the glass substrate or the like constituting the liquid crystal cell even at high temperature or high temperature and high humidity, and does not cause foaming in the adhesive layer (durability). And can be easily peeled even after a long period of time, and also has a property (reworkability) in which no residue is generated on the substrate after peeling.

  Although there is no limitation in particular as the kind of said raw film, For example, a film light-guide plate, an antireflection film, an electroconductive film, a viewing angle expansion film, a phase difference film, a polarizing plate, or the film which combined these etc. are mentioned. . Moreover, in order to improve the adhesiveness with respect to the original film of the film | membrane which consists of an adhesive composition of this invention, surface treatments, such as a corona treatment, can be performed to the surface of an original film.

  Moreover, there is no restriction | limiting in particular in the thickness of the said raw film, Although any thing can be used, For example, the thing of 5 micrometers-300 micrometers can be used, These differ with uses or the objectives.

  The optical functional film of the present invention can be produced by the following method using the optical pressure-sensitive adhesive composition of the present invention. That is, a film is obtained by coating the pressure-sensitive adhesive composition of the present invention on one or both sides of the original film using a commonly used coating apparatus such as a roll coating apparatus and drying the coating layer. (Adhesive) can be produced. Moreover, the coated adhesive layer can also be hardened | cured by light, such as heat bridge | crosslinking or an ultraviolet-ray, as needed. In addition, the optical functional film of the present invention is first coated with the optical pressure-sensitive adhesive composition of the present invention on a protective film such as a polyethylene terephthalate film (PET film) coated with a release agent such as a silicone resin, and then dried. Then, after forming the pressure-sensitive adhesive layer, it can also be produced by laminating the original film on the pressure-sensitive adhesive layer.

  In any of the above cases, the amount of the pressure-sensitive adhesive composition applied is preferably such that the thickness of the pressure-sensitive adhesive layer (film) after drying is 10 to 50 μm. By setting the thickness of the pressure-sensitive adhesive layer within the above range, an optical functional film having a better balance between durability and reworkability is obtained.

  The optical functional film of the present invention produced as described above can be stuck on a glass substrate of a liquid crystal cell such as a liquid crystal display device by means usually used. Further, the optical functional film of the present invention can be further laminated and stuck on the optical functional film stuck on the glass substrate.

Next, the present invention will be described more specifically with reference to examples and comparative examples.
<Preparation of copolymer solution>
[Synthesis Example 1-1] Production of Copolymer Solution 1 A copolymer solution was obtained by copolymerizing the following monomers using the following methods. First, nitrogen gas was introduced into a reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, and the air in the reaction apparatus was replaced with nitrogen gas. Next, in this reactor, 80 parts by mass of butyl acrylate, 20 parts by mass of methyl acrylate, 1.0 part by mass of acrylic acid, 0.4 part by mass of 2-hydroxyethyl acrylate, 0.1 mass by mass of azobisisobutyronitrile And 120 parts by weight of ethyl acetate were added. While stirring this, it was reacted at 68 ° C. for 8 hours in a nitrogen gas stream to obtain a solution of an acrylic copolymer having a weight average molecular weight of 1,500,000. The obtained copolymer solution was diluted with ethyl acetate to obtain a copolymer solution 1 having a solid content of 20%.

[Synthesis Examples 1-2 to 1-8] Production of Copolymer Solutions 2 to 8 Except that the monomer composition of Synthesis Example 1 was changed to the monomer composition shown in Table 1, the same procedure as in Synthesis Example 1-1 was performed. Copolymer solutions 2 to 8 were obtained.

Abbreviations in Table 1 indicate the following, respectively.
-BA: butyl acrylate-MA: methyl acrylate-PHEA: phenoxyethyl acrylate-MMA: methyl methacrylate-AA: acrylic acid-2HEA: 2-hydroxyethyl acrylate

<Preparation of organopolysiloxane>
(Methoxy group-containing acid anhydride / polyether co-modified polysiloxane)
[Synthesis Example 2-1]
First, methoxy group-containing methyl hydrogen polysiloxane was synthesized as follows.
In a 1 liter three-necked flask equipped with a stirrer, a thermometer, and a Dimroth condenser, tetramethoxysilane (Si) represented by R ² = CH ₃ and n = 0 in the formula [1] defined in the present invention. (OCH _{3) 4)} partially hydrolyzed condensate of the _{tetrameric; Si 4 O 3 (OCH 3} ) 10] a and 49.8 g (0.106 mol), and tetramethyl-tetrahydronaphthalene cyclotetrasiloxane 76.4 g (0 .318 mol) was charged. Thereafter, 0.102 g of trifluoromethanesulfonic acid was further added with stirring and reacted at room temperature for 4 hours. After completion of the reaction, 0.620 g of a solid basic neutralizing agent represented by Mg ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂ O was added to the system and stirred for 2 hours to neutralize trifluoromethanesulfonic acid. After the treatment, purification by filtration was performed to obtain 120 g of product-1 (methoxy group-containing methyl hydrogen polysiloxane).

  Here, GPC (Gel Permeation Chromatography) measurement was performed on the product-1 obtained after the reaction. As a result, the peaks of the raw materials (tetramethyltetrahydrocyclotetrasiloxane and methoxysiloxane) that existed at the position where the retention time was 29 minutes to 37 minutes before the reaction mostly disappeared, and instead, the retention time 28 minutes to 37 minutes. A broad equilibration peak appeared at the minute position.

Next, the methoxy group-containing methyl hydrogen polysiloxane obtained above has a monovalent hydrocarbon group Y having a polyether group as follows, and the siloxane unit B in the formula [2] defined by the present invention: The operation for introducing was performed. First, in a 1 liter three-necked flask equipped with a stirrer, a thermometer, an exhaust gas pipe and an external condenser, 120 g of the above product-1 and the following formula: CH ₂ = CH—CH ₂ —O ( 484 g (0.598 mol) of an allyl polyether represented by (CH ₂ CH ₂ CH ₂ O) ₁₂ C ₄ H ₉ was charged. Thereafter, 1.50 g of a toluene solution of chloroplatinic acid (Pt concentration: 0.5 part by mass) was added with stirring, the pressure in the system was reduced to 10 mmHg, and a hydrosilylation reaction was performed at 90 ° C. for 4 hours. It was. After completion of the reaction, the temperature was lowered to 60 ° C., and the system pressure was returned to normal pressure.

Here, the reaction rate of the allyl polyether used in the above reaction was measured as follows.
First, the ≡SiH content in 1 g of the sample before and after the reaction was measured by the following method, and the amount of allyl polyether actually reacted was calculated.
First, 1 g of the sample before and after the reaction was diluted with 10 g of butanol, and 20 g of 20 mass% NaOH aqueous solution was added while stirring. From the amount of hydrogen gas generated at this time (≡SiH + H ₂ O → ≡Si—OH + H ₂ ↑), the content (mol) of ≡SiH was calculated. Next, the reaction amount (mol) of allyl polyether actually reacted in 1 g of the sample was calculated by the following formula. Table 2 shows the results.
Reaction amount (mol) = [≡SiH content before reaction] − [≡SiH content after reaction]

In 1 g of the sample before the reaction, 9.87 × 10 ⁻⁴ mol of allyl polyether charged as a raw material is present. When the reaction rate is calculated as follows from the reaction amount obtained above and the amount charged as a raw material, it is 74.0%.
[Reaction rate = 0.73 × 10 ⁻³ (mol) /9.87×10 ⁻⁴ (mol) × 100≈74.0 (%)]
From the above, by a hydrosilylation reaction 74.0% of the charged as a raw material _{CH 2 = CH-CH 2 -O} (CH 2 CH 2 CH 2 O) 12 C 4 H 9 is a methoxy group-containing methylhydrogenpolysiloxane It was confirmed that the remaining 26.0% was introduced into the polysiloxane as an unreacted product.

Subsequently, following the introduction of the siloxane unit B having a monovalent hydrocarbon group Y having a polyether group, the siloxane unit in the formula [2] defined by the present invention having a monovalent hydrocarbon group X having an acid anhydride group The following operation for introducing A was performed.
The exhaust gas pipe was replaced with a Dimroth condenser, and 169 g (1.21 mol) of allyl succinic anhydride was added dropwise at a temperature of 60 to 70 ° C., followed by reaction at 90 ° C. for 3 hours. Here, the reaction rate of allyl succinic anhydride was measured. By the same method as described above, the ≡SiH content in 1 g of the sample before and after the reaction was measured, and the reaction amount (mol) of allyl succinic anhydride actually reacted was calculated. Table 3 shows the results obtained.

The amount of hydrogen gas generated after the reaction was almost 0 ml. From this, after introducing the siloxane unit B having a monovalent hydrocarbon group Y having a polyether group, the ≡SiH remaining in the methoxy group-containing methylhydrogensiloxane is almost entirely allyl succinic anhydride by hydrosilylation. It is thought that it reacted.
In 1 g of the sample before the reaction, 1.56 × 10 ⁻³ mol of allyl succinic anhydride charged as a raw material is present. When the reaction rate is calculated as follows from the previously obtained reaction amount and the amount charged as a raw material, it is 60.1%.
[Reaction rate = 9.37 × 10 ⁻⁴ (mol) /1.56×10 ⁻³ (mol) × 100 = 60.1 (%)]
From the above, it was confirmed that about 60% of allyl succinic anhydride charged as a raw material was introduced into methoxy group-containing methylhydrogensiloxane, and the remaining about 40% remained as an excess.

Finally, the following operation for removing excess allyl succinic anhydride was performed. The Dimroth cooling pipe was replaced with an exhaust gas pipe, and the pressure in the system was reduced to 10 mmHg, followed by heating at 110 ° C. for 10 hours under nitrogen gas bubbling. After completing the heating under reduced pressure, the temperature was cooled to room temperature, and the pressure was increased to normal pressure, and then the product was purified by filtration to obtain 636 g of liquid.
Here, GPC measurement was performed on the sample after filtration purification. In the measurement, THF was used as a solvent. The obtained results are shown in Table 4.

  Peak 1 was the peak of the target methoxy group-containing acid anhydride / polyether co-modified siloxane, and the peak area accounted for about 83% of the entire product. In addition, peak 2 occupying about the remaining 17% is considered to be allyl polyether remaining as an unreacted component because the retention time coincides with the peak of the raw material allyl polyether. In addition, since the peak of the raw material allyl succinic anhydride which appears in the vicinity of 36 to 37 minutes of retention time does not exist, it is thought that the surplus of allyl succinic anhydride was removed almost completely by the last reduced pressure heating.

Next, ²⁹ Si-NMR measurement was performed in order to analyze the structure of the obtained liquid.
As a result, first, three peaks due to the SiO _4/2 unit were present in the range of −80 ppm to −110 ppm. These peaks suggest the existence of structures represented by SiO _1/2 (OCH ₃ ) ₃ , SiO _2/2 (OCH ₃ ) ₂ , and SiO _3/2 (OCH ₃ ). In addition, two peaks due to the SiO _2/2 unit were present in the range of −5 ppm to −25 ppm. These peaks are SiO _2/2 (CH ₃ ) W, SiO _1/2 (CH ₃ ) (OCH ₃ ) W [W = X (a monovalent hydrocarbon group having an acid anhydride group of the following chemical formula), Y The existence of a structure represented by (monovalent hydrocarbon group having a polyether group of the following chemical formula) is suggested.

From these results, the structure of the obtained product is O and Si in at least one of O-Si bonds existing in the molecule of methoxypolysiloxane represented by raw material Si ₄ O ₃ (OCH ₃ ) _10. It is presumed that a siloxane bond is formed between these atoms, and both siloxane units A and B represented by the following formula are inserted.

  Here, from each raw material charge amount of methoxysiloxane, allyl polyether, allyl succinic anhydride, and the measurement result of the reaction rate, a group having an acid anhydride group introduced by reaction with respect to 1 mol of methoxysiloxane, and The amount of groups with polyether was calculated. Table 5 shows the results obtained.

  As a design, each raw material was charged in such a ratio that 6 mol of the siloxane unit A and 6 mol of the siloxane unit B were introduced with respect to 1 mol of methoxysiloxane. However, the actual product had an acid anhydride excess relative to the design as an average composition. This is considered to be because a part of the polyether charged as a raw material remained unreacted, and the amount of acid anhydride introduced was increased accordingly. Actually obtained products include, for example, a compound in which 6 mol of siloxane unit A and 6 mol of siloxane unit B are introduced, a compound in which 8 mol of siloxane unit A and 4 mol of siloxane unit B are introduced, and the like. It was estimated that some compounds with different amounts of ether introduced were mixed, and as a whole average, the composition had an excess of acid anhydride relative to the design. Moreover, it is thought that a product contains a part of raw material polyether which remained unreacted.

[Synthesis Example 2-2]
Synthesis Example 2-1, the charged amount of the allyl polyether represented by _{CH 2 = CH-CH 2 -O} (CH 2 CH 2 CH 2 O) 12 C 4 H 9, from 484g (0.598mol), 564g Except having changed to (0.696 mol), operation similar to the synthesis example 2-1 was performed, and the liquid product was obtained.
Moreover, the GPC measurement was performed regarding the sample after filtration refinement | purification similarly to the synthesis example 2-1. As a result, as in Synthesis Example 2-1, in addition to the peak of the target methoxy group-containing acid anhydride / polyether co-modified polysiloxane, an unreacted allyl polyether peak was present. In the same manner as in Synthesis Example 2-1, a siloxane unit A having a monovalent hydrocarbon group X having an acid anhydride group introduced by reaction with respect to 1 mol of methoxysiloxane, and a monovalent having a polyether group The amount of siloxane unit B having a hydrocarbon group Y was calculated. Table 5 shows the results obtained.
As a design, each raw material was charged so that 7 mol of the siloxane unit A and 5 mol of the siloxane unit B were introduced per 1 mol of methoxysiloxane. However, as in the case of Synthesis Example 2-1, part of the polyether charged as a raw material remained unreacted, so that the siloxane unit A had an excessive composition.

[Synthesis Example 2-3]
Synthesis Example 2-1, and allyl polyether represented by _{CH 2 = CH-CH 2 -O} (CH 2 CH 2 CH 2 O) 12 C 4 H 9, the charging amount 484g of (0.598mol), CH ₂ = CH—CH ₂ —O (CH ₂ CH ₂ O) ₂ (CH ₂ CH ₂ CH ₂ O) ₁₀ Except for changing to 468 g (0.598 mol) of allyl polyether represented by C ₄ H ₉ The same operation as in Example 2-1 was performed to obtain a liquid product.
Moreover, the GPC measurement was performed regarding the sample after filtration refinement | purification similarly to the synthesis example 2-1. As a result, as in Synthesis Example 2-1, in addition to the peak of the target methoxy group-containing acid anhydride / polyether co-modified polysiloxane, an unreacted allyl polyether peak was present. In the same manner as in Synthesis Example 2-1, a siloxane unit A having a monovalent hydrocarbon group X having an acid anhydride group introduced by reaction with respect to 1 mol of methoxysiloxane, and a monovalent having a polyether group The amount of siloxane unit B having a hydrocarbon group Y was calculated. Table 5 shows the results obtained.
As a design, each raw material was charged so that 6 mol of siloxane unit A and 6 mol of siloxane unit B were introduced per 1 mol of methoxysiloxane. However, as in Synthesis Examples 2-1 and 2, a portion of the polyether charged as a raw material remained unreacted, so that the siloxane unit A had an excessive composition.

[Synthesis Example 2-4]
Synthesis Example 2-1, and allyl polyether represented by _{CH 2 = CH-CH 2 -O} (CH 2 CH 2 CH 2 O) 12 C 4 H 9, the charging amount 484g of (0.598mol), CH ₂ = CH—CH ₂ —O (CH ₂ CH ₂ O) _{10 The same} procedure as in Synthesis Example 2-1 was performed, except that it was changed to 484 g (0.598 mol) of allyl polyether represented by C ₄ H _9. As a result, a liquid product was obtained.
Moreover, the GPC measurement was performed regarding the sample after filtration refinement | purification similarly to the synthesis example 2-1. As a result, as in Synthesis Example 2-1, in addition to the peak of the target methoxy group-containing acid anhydride / polyether co-modified polysiloxane, an unreacted allyl polyether peak was present. In the same manner as in Synthesis Example 2-1, a siloxane unit A having a monovalent hydrocarbon group X having an acid anhydride group introduced by reaction with respect to 1 mol of methoxysiloxane, and a monovalent having a polyether group The amount of siloxane unit B having a hydrocarbon group Y was calculated. Table 5 shows the results obtained.
As a design, each raw material was charged so that 6 mol of the siloxane unit A and 6 mol of the siloxane unit B were introduced per 1 mol of methoxysiloxane. However, as in Synthesis Examples 2-1 to 2-3, a portion of the polyether charged as a raw material remained unreacted, so that the siloxane unit A had an excessive composition.

<Production of pressure-sensitive adhesive composition, production and evaluation of polarizing plate>
[Examples 1 to 18, Comparative Examples 1 to 5]
With respect to 100 parts by mass of the solid content of the copolymers obtained in Synthesis Examples 1-1 to 1-8, each component shown in Table 6 was added and blended, and Examples 1 to 18 and Comparative Examples 1 to 5 Each adhesive composition was obtained.

[Example 19]
In Example 19, tris (2-acrylic acid) was used as a monomer having at least two polymerizable reactive double bonds with respect to 100 parts by mass of the solid content of the copolymer 5 obtained in Synthesis Example 1-5. 10 parts by weight of (roxyethyl) isocyanurate and 30 parts by weight of butyl acrylate, which is a monomer having only one reactive double bond, and 2,4,6-trimethylbenzoyl-diphenyl as a photopolymerization initiator -Adhesion of Example 19 by adding 9.0 parts by mass of Coronate L and 0.5 parts by mass of Product-1 obtained in Synthesis Example 2-1 to 0.1 parts by mass of phosphine oxide An agent composition was obtained.

In Tables 6-1 and 2, the following are shown.
Coronate L: manufactured by Nippon Polyurethane Industry Co., Ltd., polyisocyanate compound. Tetrad X: manufactured by Mitsubishi Gas Chemical Co., Ltd., polyglycidyl compound. Tetrad C: manufactured by Mitsubishi Gas Chemical Co., Ltd., polyglycidyl compound. Aluminum chelate A: Aluminum tris (acetylacetonate), manufactured by Kawaken Fine Chemicals Co., Ltd.
TAZM: trimethylolpropane-tri-β-aziridinyl propionate X-41-1810: manufactured by Shin-Etsu Chemical Co., Ltd., methyl mercapto-based alkoxy oligomer KBM-403: manufactured by Shin-Etsu Chemical Co., Ltd. γ-glycidoxypropyltrimethoxysilane / KBE-402: manufactured by Shin-Etsu Chemical Co., Ltd., γ-glycidoxypropylmethyldiethoxysilane / X-12-641: manufactured by Shin-Etsu Chemical Co., polyether modified Silane, SCA-A: Commercially available organosiloxane oligomer, TAI: Tris (2-acryloxyethyl) isocyanurate, BA: Butyl acrylate

<Production and Evaluation of Polarizing Plate>
The adhesive composition of Example 1 obtained above was applied onto a silicone resin-coated PET film (releasable substrate) and then dried at 90 ° C. to remove the solvent, and the thickness was 25 μm. An adhesive layer was formed. A polarizing film having a thickness of 180 μm was bonded to the surface on which the pressure-sensitive adhesive layer was formed, and then cured for 7 days in an atmosphere of 23 ° C. and 50% RH, thereby producing the polarizing plate of Example 1. In the same manner as described above, each polarizing plate of Examples 2 to 18 and Comparative Examples 1 to 5 was obtained using each of the pressure-sensitive adhesive compositions of Examples 2 to 18 and Comparative Examples 1 to 5 described in Table 6.

  In Example 19, the pressure-sensitive adhesive composition of Example 19 was dried by the same operation to form a pressure-sensitive adhesive layer, and then a 180 μm-thick polarizing film was bonded, followed by a PET film (release property) The crosslinking of the monomer was completed by irradiating ultraviolet rays from the substrate side. Further, the polarizing plate of Example 19 was obtained by curing for 7 days in an atmosphere of 23 ° C. and 50% RH.

  Each of these polarizing plates was evaluated for reworkability, durability, and color unevenness (white spots) by the test methods and evaluation criteria described below, and the evaluation results are shown in Table 7. The evaluation results of the pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition of the examples are good in all items, and are clearly superior to the results of the comparative examples as shown in the results shown in Table 7-2. And its superiority was confirmed.

<Test method and evaluation criteria>
[Reworkability test]
After each polarizing plate in Examples and Comparative Examples was cut to a size of 50 mm × 50 mm, the PET film was peeled off and bonded to a glass plate, and then held and bonded for 20 minutes at a temperature of 50 ° C. and a pressure of 0.5 MPa. A test sample was prepared. After leaving at 23 ° C. and 50% RH for 1 hour, the sample was peeled off from the glass plate by hand, and the presence or absence of transfer of the adhesive to the glass was evaluated by visual observation. Further, each sample prepared in the same manner was left to stand at 70 ° C. for 17 hours, then allowed to cool to 23 ° C., and left for 1 hour at this temperature to conduct a paste residue test, and evaluated according to the following criteria. As a result of the above test, it was confirmed that the pressure-sensitive adhesive having good removability does not transfer the pressure-sensitive adhesive to the glass regardless of the presence or absence of heating.

・ Evaluation criteria (adhesive residue)
○: No transfer of adhesive to the glass plate.
X: Transfer of adhesive on glass plate.

[Durability test]
Each polarizing plate in Examples and Comparative Examples was cut to 300 mm × 400 mm and the PET film was peeled off, and then applied to a glass substrate and subjected to an autoclave treatment to prepare a sample for evaluation. About the obtained sample for evaluation, the test of the following item was performed, respectively.

<Durability against harsh environmental conditions>
Each evaluation sample prepared above was left to stand in an atmosphere of 80 ° C. (DRY) and an atmosphere of 60 ° C. and 90% RH for 500 hours, and a durability test was performed. Thereafter, the foaming and peeling were visually confirmed and evaluated according to the following evaluation criteria.
(Evaluation criteria)
(1) Foaming ○: Foaming is not confirmed on the polarizing plate.
Δ: Slight foaming was confirmed on the polarizing plate.
X: Foaming was confirmed on the polarizing plate.
(2) Peeling ○: Peeling is not confirmed on the polarizing plate.
Δ: Slight peeling was confirmed on the polarizing plate.
X: Peeling was confirmed on the polarizing plate.

<White spot test>
Two of the same samples after the 80 ° C. (DRY) endurance test using each polarizing plate in Examples and Comparative Examples were used and bonded in crossed Nicols on the upper and lower surfaces of the liquid crystal panel, and the backlight of the liquid crystal monitor was turned on. The white spots were visually observed.

(Evaluation criteria)
○: No white spots were observed on the polarizing plate.
Δ: Slight white spots were observed on the polarizing plate.
X: White spots were observed on the polarizing plate.

Claims (10)

0.001 to 5.0 parts by mass of organopolysiloxane (b) and / or a hydrolysis condensate thereof is added to 100 parts by mass of the copolymer (a) containing (meth) acrylic acid ester. And
The organopolysiloxane (b) is an O-Si bond present in the molecule of an alkoxysilane represented by the following formula [1] or a partially hydrolyzed condensate thereof, and is between O and Si atoms. A compound having an alkoxy group, an acid anhydride group, and a polyether group in the molecule, wherein at least two types of siloxane units are inserted to form a siloxane bond, and
The siloxane unit inserted is 1 to 100 siloxane units represented by the following formula [2], and a siloxane unit represented by 1 to 100 siloxane units represented by the following formula [2]: Furthermore, it is the siloxane unit represented by the C formula of following [2] Formula of 0-100 pieces inserted as needed, The optical adhesive composition characterized by the above-mentioned.
[1] Formula R ¹ _n Si (OR ² ) _4-n
(In the formula [1], R ¹ represents a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom. R ² represents an alkyl group having 1 to 10 carbon atoms. n represents 0 or 1.)

([2] In the formula, X represents a monovalent hydrocarbon group having an acid anhydride group. Y represents a group having a monovalent hydrocarbon having a polyether group. R ³ is independently A hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom.) In the formula [2], X in the formula A is a monovalent hydrocarbon group having an acid anhydride group represented by the following formula [3], and Y in the formula B is represented by the following formula [4]. The optical pressure-sensitive adhesive composition according to claim 1, wherein the polyorganosiloxane (b), which is a monovalent hydrocarbon group having a represented polyether group, each having a siloxane unit inserted therein is blended.

([3] In the formula, A represents a linear or branched alkylene group having 2 to 6 carbon atoms.)
[4] formula _{-C m H 2m -O (C 2} H 4 O) p (C 3 H 6 O) q R 4
(In the formula [4], R ⁴ represents any one of a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following formula [5]. M is an integer of 1 or more. P and q represent an integer of 0 or more, provided that at least one of p and q is an integer of 1 or more.)

(In the formula [5], R ⁵ represents a monovalent hydrocarbon group having 1 to 4 carbon atoms.)   Y in the formula B is a monovalent hydrocarbon having a propylene oxide type polyether group represented by the above formula [4], wherein p is 0 and q is an integer of 1 or more The optical pressure-sensitive adhesive composition according to claim 2, which is a group.   The optical pressure-sensitive adhesive composition according to any one of claims 1 to 3, wherein at least the organosiloxane (b) into which the siloxane unit represented by the formula C of the formula [2] is not inserted is blended. .   The copolymer (a) containing the (meth) acrylic acid ester is a copolymer having at least an alkyl (meth) acrylate monomer having an organic substituent having 1 to 18 carbon atoms in the side chain as a forming component. And the weight average molecular weight of this copolymer is 400,000-2 million, The optical adhesive composition of any one of Claims 1-4.   The cross-linking agent (e) is further added in an amount of 0.01 to 40 parts by mass with respect to 100 parts by mass of the copolymer (a) containing the (meth) acrylic acid ester. The optical pressure-sensitive adhesive composition according to Item.   The optical pressure-sensitive adhesive composition according to claim 6, wherein the crosslinking agent (e) is at least one selected from the group consisting of an isocyanate crosslinking agent, an epoxy crosslinking agent, a metal crosslinking agent, and an aziridine crosslinking agent.   The optical pressure-sensitive adhesive composition according to any one of claims 1 to 7, wherein a silane coupling agent (f) other than the organopolysiloxane (b) and / or a hydrolysis condensate thereof is further added.   The addition amount of the silane coupling agent (f) and / or the hydrolysis condensate thereof is 0.01 to 5 parts by mass with respect to 100 parts by mass of the copolymer (a) containing the (meth) acrylic acid ester. The optical pressure-sensitive adhesive composition according to claim 8.   An optical functional film, wherein a film made of the optical pressure-sensitive adhesive composition according to claim 1 is laminated on one side or both sides.