JP5262672B2 - Pressure-sensitive adhesive composition for liquid crystal elements - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure-sensitive adhesive which is suitable for adhesion of a glass substrate and a polarizing plate to each other, or for adhesion of a laminated plate of a polarizing plate and a retardation plate. <P>SOLUTION: The pressure-sensitive adhesive composition for a liquid crystal element includes an acrylic polymer (A), and an adhesion modifier (B) including an organopolysiloxane compound represented by average composition formula (1): Y<SB>a</SB>R<SP>1</SP><SB>b</SB>R<SP>2</SP><SB>c</SB>Si(OR<SP>3</SP>)<SB>d</SB>(OH)<SB>e</SB>O<SB>(4-a-b-c-d-e)/2</SB>. In above formula, Y is a &beta;-ketoester group containing organic group, wherein a part of Y is optionally enolized, R<SP>1</SP>is a 1-18C monovalent hydrocarbon group including or not including a functional group such as a mercapto group and an epoxy group, R<SP>2</SP>does not contain any functional group, and is a 1-18C monovalent hydrocarbon group different from R<SP>1</SP>, R<SP>3</SP>is a 1-4C monovalent hydrocarbon group, and a, b, c, d, and e are numbers respectively represented by 0.01&le;a&le;1, 0&le;b&lt;1, 0&le;c&le;2, 0&le;d&le;2, and 0&le;e&le;1, and satisfying inequality 2&le;a+b+c+d+e&le;3. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a pressure-sensitive adhesive composition for a liquid crystal display device using a novel adhesion modifier. More specifically, a pressure-sensitive adhesive for liquid crystal elements that can be peeled off at the time of manufacturing a liquid crystal display device, but becomes more adhesive over time and exhibits excellent durability when used under high temperature and high humidity conditions. Relates to the composition.

  The liquid crystal element is arranged on two glass substrates in which a transparent electrode is disposed on a surface in contact with the liquid crystal, a liquid crystal material filled between the two glass substrates, and an outer surface of the two glass substrates. It consists of a polarizing plate or a laminated plate of a polarizing plate and a retardation plate.

  In such a liquid crystal element, a polarizing plate or a laminated plate of a polarizing plate and a retardation plate is bonded to the surface of a glass substrate using an acrylic resin pressure sensitive adhesive, for example.

  In the manufacturing process of a liquid crystal element using such a pressure-sensitive adhesive, when a problem occurs in the bonding of the polarizing plate or the laminated plate of the polarizing plate and the retardation plate to the glass substrate, If the laminated plate with the retardation plate can be peeled off from the glass substrate and a new polarizing plate or a laminated plate of the polarizing plate and the retardation plate can be attached to the glass substrate again, an expensive liquid crystal material and this liquid crystal material will be filled. A liquid crystal element exhibiting good liquid crystal performance can be produced without discarding the cell itself. From such a viewpoint, it is desirable that the pressure-sensitive adhesive is easily peeled off when a failure occurs at the stage of bonding the polarizing plate or the laminated plate of the polarizing plate and the retardation plate to the glass substrate. .

  On the other hand, in recent years, the use range of liquid crystal elements such as personal computers, in-vehicle liquid crystal monitors, and television screens has been remarkably wide. Yes. Accordingly, it is desirable that the adhesive strength between the polarizing plate or the laminated plate of the polarizing plate and the retardation plate and the glass substrate is higher so as to withstand such use conditions, and that the high adhesive strength does not change for a long time. It is done.

  As described above, the pressure-sensitive adhesive used for adhering the polarizing plate or the laminated plate of the polarizing plate and the retardation plate to the glass substrate of the liquid crystal element is liquid crystal when it is going to be peeled off when a malfunction occurs in the manufacturing process. After the polarizing plate or the laminated plate of the polarizing plate and the retardation plate can be easily peeled from the substrate without damaging the device, on the other hand, after the liquid crystal device is actually used and used in various applications, The contradictory property that a stable adhesive strength is maintained for a long time is required.

  Conventionally, acrylic resin-based pressure-sensitive adhesives that use an organosilicon compound with a β-ketoester structure in the molecule as an adhesive modifier will damage the liquid crystal element when it is peeled off when a failure occurs during the manufacturing stage. The polarizing plate or the laminated plate of the polarizing plate and the retardation plate can be easily peeled from the substrate without giving, and after the liquid crystal element is actually used in various applications, the stable adhesive strength is maintained for a long time. This is known, for example, from Patent Document 1 and the like. However, even when such a conventionally known organosilicon compound having a β-ketoester structure is used, the long-term stability of adhesive strength is still insufficient under the severe environment demanded in recent years. There is a need for improvement.

Japanese Patent No. 3533446

  This invention makes it a subject to provide the pressure sensitive adhesive composition especially suitable for adhesion | attachment with the laminated board of a glass substrate and a polarizing plate or a glass substrate, and a polarizing plate and a phase difference plate.

  More specifically, the object of the present invention is to adhere a polarizing plate or a laminated plate of a polarizing plate and a retardation plate to a glass substrate constituting a liquid crystal element with an appropriate strength, and in the manufacturing process, this polarization When it becomes necessary to peel off a plate or a laminate of a polarizing plate and a retardation plate, it can be peeled off without damaging a liquid crystal cell such as a glass substrate, and an adhesive is applied on the glass substrate. It is an object of the present invention to provide a pressure-sensitive adhesive composition for a liquid crystal element that can maintain a stable and strong adhesive strength for a long period of time after the liquid crystal element is practically used in various applications.

The present inventors have solved the above problem.
(A) an acrylic polymer;
(B) The following average composition formula (1):
Y _a R ¹ _b R ² _c Si (OR ³ ) _d (OH) _e O _{(4-abbcde) / 2}
... (1)
(Where
Y is an organic group containing a β-ketoester group which may be at least partially enolized,
R ¹ is a hydrocarbyl in which a mercapto group, an epoxy group, an acryloyloxy group, a methacryloyloxy group, an alkenyl group, an amino group, a halogen atom, and an enolized β-ketoester group are represented by the formula OR ³ in or between molecules. A monovalent hydrocarbon group having 1 to 18 carbon atoms, which contains or does not contain at least one functional group selected from the group consisting of groups formed by reaction with an oxy group,
R ² does not contain a functional group and is a monovalent hydrocarbon group having 1 to 18 carbon atoms different from R ¹ ;
R ³ is a monovalent hydrocarbon group having 1 to 4 carbon atoms,
a, b, c, d, and e are numbers represented by 0.01 ≦ a ≦ 1, 0 ≦ b <1, 0 ≦ c ≦ 2, 0 ≦ d ≦ 2, and 0 ≦ e ≦ 1, respectively. And 2 ≦ a + b + c + d + e ≦ 3. )
An adhesive modifier comprising an organopolysiloxane compound containing a β-ketoester group-containing organic group and a hydrocarbyloxy group in one molecule;

A pressure-sensitive adhesive composition for liquid crystal elements in which the adhesive modifier of component (B) is in the proportion of 0.001 to 10 parts by mass with respect to 100 parts by mass of the acrylic polymer of component (A). It was found that this can be solved.

  The pressure-sensitive adhesive composition for a liquid crystal device of the present invention adheres a glass substrate and a polarizing plate or a laminated plate of a polarizing plate and a retardation plate with necessary and sufficient adhesive strength in the manufacturing process of the liquid crystal device. Can do. In the production process, the adhesive strength is not excessively high and is maintained at an appropriate level even when the adhesive composition is subjected to heating or the like. For this reason, if there is a problem in bonding during the manufacturing process, the polarizing plate or the laminated plate of the polarizing plate and the retardation plate can be easily peeled off from the glass substrate, and in that case, the adhesive remains on the substrate. However, it is rare that the glass substrate or the liquid crystal cell is damaged during peeling.

  Furthermore, the pressure-sensitive adhesive composition of the present invention exhibits appropriate adhesiveness and peelability as described above in the manufacturing process of the liquid crystal element, while the completed liquid crystal element is actually used for various applications. Even if exposed to harsh conditions such as high temperature and high humidity, the necessary and sufficient adhesive strength can be stably maintained over a long period of time, and adhesion failure such as swelling or peeling may occur on the polarizing plate or the laminated plate of polarizing plate and retardation plate. Hard to occur.

  Next, the pressure-sensitive adhesive composition for liquid crystal elements of the present invention will be specifically described.

  The pressure-sensitive adhesive composition for liquid crystal elements of the present invention contains an acrylic polymer as a main component and an organopolysiloxane compound having a specific novel β-ketoester structure as an adhesive modifier. Hereinafter, description will be made sequentially.

-(A) Acrylic polymer-
The acrylic polymer as component (A) has an effect of imparting pressure-sensitive adhesiveness to the composition of the present invention.

  In the present invention, the “acrylic polymer” is a polymer of an acrylic monomer (that is, a homopolymer and a copolymer). Acrylic monomers include acrylic acid monomers and methacrylic acid monomers.

  Examples of the acrylic acid monomer include acrylic acid, acrylic acid ester, and acrylamide. Examples of the acrylate esters include alkyl acrylate esters such as methyl acrylate, ethyl acrylate, and butyl acrylate.

  Examples of the methacrylic acid monomer include methacrylic acid, methacrylic acid ester, and methacrylic acid amide. Examples of methacrylic acid esters include methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, and butyl methacrylate.

  In this specification, terms such as “(meth) acrylic acid” and “(meth) acrylate” are respectively used as a general concept of acrylic acid and methacrylic acid, a general concept of acrylate and methacrylate, and the like.

  The acrylic polymer used in the present invention may be a single polymer of the above monomers or a copolymer of two or more monomers. Among these, a copolymer containing an acrylic monomer having no functional group and an acrylic monomer having a functional group is preferable. Here, examples of the functional group include a carboxyl group, a hydroxy group, an amino group, an epoxy group, and an amide group.

  Examples of acrylic monomers having no functional group include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate And alkyl (meth) acrylates such as stearyl (meth) acrylate, cyclohexyl (meth) acrylate, methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate. These can be used singly or in combination of two or more.

  The acrylic polymer used in the present invention preferably has 60 to 99% by mass, more preferably 80 to 98% by mass of a repeating unit derived from a (meth) acrylic acid ester having no functional group. ing.

  Examples of acrylic monomers having functional groups include acrylic acid, methacrylic acid, β-carboxyethyl acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, chloro-2-hydroxypropyl Functional group-substituted alkyl (meth) acrylates such as (meth) acrylate and dimethylaminoethyl (meth) acrylate, diethylene glycol mono (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide, N-methylol (meth) acrylamide and N -Ethylol (meth) acrylamide etc. can be mentioned. These can be used singly or in combination of two or more.

  The acrylic polymer used in the present invention preferably has a repeating unit derived from the functional group-containing acrylic monomer, usually in an amount of 1 to 20% by mass, preferably 2 to 10% by mass. Yes.

  The acrylic polymer used in the present invention may have a repeating unit derived from an acrylic monomer having no functional group and a monomer other than the acrylic monomer having a functional group. Examples include repeating units derived from styrene monomers and repeating units derived from vinyl monomers.

  Specific examples of styrene monomers include alkyl styrene such as styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene and octyl styrene. Halogenated styrenes such as fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene, and iodostyrene; and further, nitrostyrene, acetylstyrene, methoxystyrene, and the like.

  Examples of vinyl monomers include vinyl pyridine, vinyl pyrrolidone, vinyl carbazole, divinyl benzene, vinyl acetate and acrylonitrile; conjugated diene monomers such as butadiene, isoprene and chloroprene; vinyl halides such as vinyl chloride and vinyl bromide; And vinylidene halides such as vinylidene chloride.

  These monomers can be used singly or in combination of two or more. In the acrylic polymer used in the present invention, the repeating unit derived from the other monomer is usually contained in an amount of 0 to 20% by mass, preferably 0 to 10% by mass.

  The acrylic polymer used in the present invention is necessary after a known method, for example, by introducing the above monomer into the reaction solvent and replacing the air in the reaction system with an inert gas such as nitrogen gas. Can be produced by heating and stirring in the presence of a reaction initiator to cause a polymerization reaction.

  Use of the reaction solvent is optional, and usually an organic solvent is used. For example, aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as n-hexane, and esters such as ethyl acetate and butyl acetate. And alcohols such as n-propyl alcohol and i-propyl alcohol, and ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

  When a reaction initiator is used, for example, azobisisobutyronitrile, benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide and the like can be used.

  The reaction temperature of the above polymerization reaction may be about 50 to 90 ° C., and the reaction time is about 2 to 20 hours, preferably 4 to 12 hours. In the reaction as described above, the monomer is charged corresponding to the amount of each repeating unit in the acrylic polymer to be obtained. Moreover, when using a reaction solvent, it is used in the quantity of 50-300 mass parts with respect to 100 mass parts of total amounts of a monomer. Further, the reaction initiator is usually used in an amount of 0.01 to 10 parts by mass.

  By making it react in this way, the acryl-type polymer used by this invention is obtained as a solution or dispersion liquid in which the (co) polymer is contained in the reaction solvent in an amount of 25 to 70% by mass. In the present invention, the acrylic polymer and other components may be mixed in a state dispersed in the reaction solvent without removing the reaction solvent obtained as described above.

  The acrylic polymer used in the present invention usually has a weight average molecular weight of 100,000 to 1500,000, preferably 300,000 to 800,000. In addition, you may mix | blend other components, such as an inorganic filler, with this acrylic polymer in the range which does not impair the objective of this invention.

-(B) Adhesive modifier-
As described above, the organopolysiloxane compound used in the present invention has an average composition formula (1):
Y _a R ¹ _b R ² _c Si (OR ³ ) _d (OH) _e O _{(4-abbcde) / 2} (1)
It is represented by The organopolysiloxane compound is a compound containing a β-ketoester group and a hydrocarbyloxy group as reactive groups in one molecule. At least a part of the β-ketoester group may be enolized (ie, tautomerized to form an enol form), but in the following description, it is also simply referred to as “β-ketoester group”.

In the above formula (1), Y represents a β-ketoester group-containing organic group.
-Q-Z
(In the formula, Z is a β-ketoester group, and Q is a divalent hydrocarbon group.)
It is represented by

  Here, as Z, the formula:

(Wherein R ⁴ represents an alkyl group having 1 to 10 carbon atoms, or a phenyl group having or not having a substituent, and a methyl group is particularly preferred)
The β-ketoester group represented by The alkyl group represented by R ⁴ is preferably an alkyl group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, and more preferably 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, and a butyl group. A methyl group is particularly preferred.

Examples of the substituted phenyl group represented by R ⁴ include a phenyl group substituted with a halogen atom such as chlorine and bromine, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and the like.

  The divalent hydrocarbon group for Q is preferably a group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, and particularly preferably an alkylene group such as a methylene group, an ethylene group, a propylene group, a butylene group, or a hexylene group, A propylene group is particularly preferable.

R ¹ is a hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms, and may be optionally substituted with at least one specific functional group. Examples of the hydrocarbon group having 1 to 18 carbon atoms include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, hexyl group, octyl group; phenyl group Aryl groups such as tolyl group; aralkyl groups such as benzyl group and phenylethyl group. A propyl group is particularly preferable. When only the characteristic of the β-ketoester group-containing organic group (Y) is expected in the organopolysiloxane compound used in the present invention, the specific functional group may not be contained. However, in the case of imparting other characteristics in addition to the characteristics of the β-ketoester group-containing organic group, the specific functional group can be included in the molecule. The specific functional group is selected according to the property to be imparted to the organopolysiloxane. In particular, it preferably contains a mercapto group and / or an epoxy group.

  In the above, “the group formed by the reaction of the enolized β-ketoester group with the hydrocarbyloxy group within or between the molecules of the organopolysiloxane compound” was formed by an intramolecular or intermolecular exchange reaction. It means a cross-linked structure.

R ² is a monovalent hydrocarbon group containing no functional group and having 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms, different from R ¹ . For example, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, hexyl group, octyl group, decyl group and octadecyl group; aryl groups such as phenyl group and tolyl group An aralkyl group such as a benzyl group or a phenylethyl group; A methyl group is particularly preferable.

R ³ represents a monovalent hydrocarbon group having 1 to 4 carbon atoms, and examples thereof include alkyl groups such as a methyl group, an ethyl group, a propyl group, and a butyl group. Among these, a methyl group and an ethyl group are particularly preferable.

  a, b, c, d, and e are numbers of 0.01 ≦ a ≦ 1, 0 ≦ b <1, 0 ≦ c ≦ 2, 0 ≦ d ≦ 2, and 0 ≦ e ≦ 1, respectively. And 2 ≦ a + b + c + d + e ≦ 3 is satisfied.

Here, a is a numerical value representing the ratio of the number of β-ketoester group-containing organic groups (Y) to the number of silicon atoms in the organopolysiloxane compound. If this a is less than 0.01, the desired property due to the reactivity of the organic group containing a β-ketoester group is not exhibited when the organopolysiloxane compound is used. On the other hand, it is difficult to make a larger than 1 in terms of the synthesis method and cost. Therefore, a needs to be in the range of 0.01 ≦ a ≦ 1, preferably in the range of 0.1 ≦ a ≦ 1, and more preferably in the range of 0.1 ≦ a ≦ 0.8.

Further, b is a numerical value representing the ratio of the number of monovalent hydrocarbon groups (R ¹ ) having ^{1 to} 18 carbon atoms that may contain a specific functional group with respect to the number of silicon atoms in the organopolysiloxane compound, When this is 0 or relatively small, the content of hydrocarbyloxy groups (OR ³ ) such as alkoxy groups is relatively increased and hydrolysis and silylation reactions are likely to occur. Affinity for is improved.

On the other hand, when b is relatively large, when R ¹ has the specific functional group, reactivity with organic resins such as epoxy resin, urethane resin, polyamide resin, polyimide resin, polyester resin, acrylic resin, etc. When the specific functional group is not present, depending on the type of the monovalent hydrocarbon group (R ¹ ), hydrophobicity is imparted to the organopolysiloxane compound (R ¹ is, for example, an alkyl group) In addition, the affinity or compatibility of the organopolysiloxane compound with an organic compound or an organic resin is improved (when R ¹ is, for example, a phenyl group). However, in this case, since the content of hydrocarbyloxy groups such as alkoxy groups is relatively reduced, the reactivity of hydrocarbyloxysilyl groups and the like is lowered. Therefore, the value of b needs to be selected within the range of 0 ≦ b <1, depending on the purpose of use of the organopolysiloxane, preferably in the range of 0 ≦ b ≦ 0.8, more preferably 0 ≦ b ≦ 1. The range is 0.5.

c is a numerical value representing the ratio of the number of monovalent hydrocarbon groups (R ² ) having 1 to 18 carbon atoms that does not contain a functional group and is different from R ¹ with respect to the number of silicon atoms in the organopolysiloxane compound. . When c is 0 or relatively small, the content of a hydrocarbyloxy group (OR ³ ) such as an alkoxy group is relatively increased, so that a hydrolysis reaction or a silylation reaction easily occurs. In some cases, the organopolysiloxane compound Improves water affinity. On the other hand, when c is relatively large, effects such as imparting hydrophobicity to the organopolysiloxane compound and imparting flexibility and releasability to the cured product of the organopolysiloxane compound can be obtained. However, in this case, when the content of the hydrocarbyloxy group is relatively decreased, the reactivity of the hydrocarbyloxysilyl group is lowered. Therefore, the numerical value of c needs to be selected within the range of 0 ≦ c <2 according to the purpose of use, preferably in the range of 0 ≦ c ≦ 1, more preferably in the range of 0 ≦ c ≦ 0.8. It is a range.

In the organopolysiloxane, d is a numerical value representing the ratio of the number of hydrocarbyloxy groups (OR ³ ) to the number of silicon atoms, and can be appropriately set according to the purpose of use. The range is 0 ≦ d ≦ 2, and when this value is 0 or close to 0, the reactivity of the organopolysiloxane to the inorganic material is low, and when close to 2, the reactivity to the inorganic material is reversed. To be higher. Preferably, the range is 0 ≦ d ≦ 1.8.

  In the organopolysiloxane, e is a numerical value representing the ratio of the number of hydroxyl groups (OH) to the number of silicon atoms, in other words, the content of silanol groups. This silanol group can participate in a silylation reaction or a condensation reaction, and has an action of imparting hydrophilicity to the organopolysiloxane compound. However, from the viewpoint of maintaining good storage stability of the organopolysiloxane compound, it is preferable to reduce it as much as possible. Therefore, it is necessary to set the range of 0 ≦ e ≦ 1, preferably 0 ≦ e ≦ 0.5, and more preferably 0 ≦ e ≦ 0.2.

  The sum of a + b + c + d + e is a numerical value that determines [4- (a + b + c + d + e)] / 2 representing the degree of condensation of the organopolysiloxane compound represented by the above average composition formula (1), and is in the range of 2 ≦ a + b + c + d + e ≦ 3 It is necessary.

  The degree of polymerization of the individual molecules of the organopolysiloxane compound can be in the range of 2 to several hundreds. That is, it can range from a dimer of 2 silicon atoms to a polymer of about several hundred silicon atoms. However, when the average degree of polymerization is 2, the content of the monomer in the organopolysiloxane compound increases, and the intended purpose (that is, low volatility) of the silicone hydrocarbyloxy oligomer is impaired. On the other hand, if the average degree of polymerization is too large, the organopolysiloxane compound becomes difficult to handle because it is in a high-viscosity state, a paste, or a solid. Therefore, the average degree of polymerization is preferably in the range of 3 to 100, more preferably in the range of 3 to 50, particularly 6 to 20. From such a viewpoint, the numerical value of (a + b + c + d + e) described above is preferably in a range of 2.02 ≦ a + b + c + d + e ≦ 2.67, and more preferably in a range of 2.04 ≦ a + b + c + d + e ≦ 2.67.

  The molecular structure of the organopolysiloxane compound used in the present invention may be linear, branched or cyclic, and may have a structure in which these are combined. The organopolysiloxane compound is usually not a single structure but a mixture of molecules having various structures.

<Manufacturing method>
The organopolysiloxane compound used in the present invention can be obtained by various conventionally known methods. The manufacturing method 1 and the manufacturing method 2 mentioned above are mentioned as a typical manufacturing method, It demonstrates in detail below.

-Manufacturing method 1
The method is (a) a method in which at least one β-ketoester group-containing hydrocarbyloxysilane represented by the following general formula (2), a partial hydrolyzate thereof, or a combination thereof is subjected to partial hydrolysis and polycondensation alone. is there.

-Manufacturing method 2-
This method includes (a) at least one β-ketoester group-containing hydrocarbyloxysilane represented by the following general formula (2), a partial hydrolyzate thereof, or a combination thereof,
(B) Hydrocarbyloxysilane represented by the following general formula (3), a partial hydrolyzate thereof, hydrocarbyloxysilane represented by the following general formula (4), a partial hydrolyzate thereof, and at least one of these This is a method in which at least one compound selected from the group consisting of condensates is partially cohydrolyzed and polycondensed.

YR ² _m Si (OR ³ ) _3−m (2)
R ¹ R ² _n Si (OR ³ ) _3−n (3)
R ² _p Si (OR ³ ) _4−p (4)
(In the formula, Y, R ¹ , R ² and R ³ each have the same meaning as above, m is an integer of 0 to 2, n is an integer of 0 to 2, and p is an integer of 0 to 3. .)

  The following are illustrated as a compound represented by Formula (2).

The compound represented by the general formula (3) will be described. R ¹ is a hydrocarbon group having 1 to 18 carbon atoms with or without a specific functional group.

  The example of a C1-C18 hydrocarbon group which does not have a specific functional group is as above-mentioned. Examples of the hydrocarbon group having 1 to 18 carbon atoms having a specific functional group include a mercaptomethyl group, a 3-mercaptopropyl group, a 6-mercaptohexyl group, a 10-mercaptodecyl group, and 4- (mercaptomethyl) phenylethyl. Group, glycidoxymethyl group, 3-glycidoxypropyl group, 5,6-epoxyhexyl group, 9,10-epoxydecyl group, 2- (3,4-epoxycyclohexyl) ethyl group, 2- (3 4-epoxy-4-methylcyclohexyl) propyl group, acryloyloxymethyl group, 3-acryloyloxypropyl group, 6-acryloyloxyhexyl group, 10-acryloyloxydecyl group, methacryloyloxymethyl group, 3-methacryloyloxypropyl group, 6-methacryloyloxyhexyl group, 10-methacrylate Royloxydecyl group, vinyl group, allyl group, 5-hexenyl group, 9-decenyl group, 3-vinyloxypropyl group, p-styryl group, cyclohexenylethyl group, chloromethyl group, 3-chloropropyl group, 6- Chlorohexyl group, 10-chlorodecyl group, bromomethyl group, 3-bromopropyl group, trifluoropropyl group, heptadecafluorodecyl group, aminomethyl group, 3-aminopropyl group, 2-aminopropyl group, N-methyl-3 -Aminopropyl group, N, N-dimethyl-3-aminopropyl group, N-phenyl-3-aminopropyl group, N- (2-aminoethyl) -3-aminopropyl group, N- (6-aminohexyl) -3-aminopropyl group, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyl group and the like can be mentioned.

  Examples of the alkoxysilane represented by the general formula (3) and having a specific functional group include trimethoxysilane and triethoxysilane having a hydrocarbon group having 1 to 8 carbon atoms having the specific functional group exemplified above. Methyldimethoxysilane, methyldiethoxysilane, ethyldimethoxysilane, ethyldiethoxysilane, propyldimethoxysilane, propyldiethoxysilane, dimethylmethoxysilane, dimethyldiethoxysilane, ethoxydimethoxysilane, and methoxydiethoxysilane.

  More specifically, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxy (Cyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, chloropropyltrimethoxysilane, chloropropyltriethoxysilane, trifluoropropyltrimethoxysilane, heptadecafluorodecyltrimethoxysilane, propyl Trimethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, 3-mercaptopropylmethyldimethycisilane, 3-mercaptopropylmethyldiethoxysilane, 3-glycidoxypropylmethyl Dimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, chloropropylmethyldimethoxysilane, Examples include chloropropylmethyldiethoxysilane, trifluoropropylmethyldimethoxysilane, heptadecafluorodecylmethyldimethoxysilane, propylmethyldimethoxysilane, hexylmethyldimethoxysilane, and decylmethyldimethoxysilane.

  Among these, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) Ethyltrimethoxysilane and 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane are preferred.

The hydrocarbyloxy group containing silane represented by General formula (4) is illustrated. Specifically, examples of the hydrocarbyloxysilane in which p = 0 in the general formula (4) include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraisobutoxysilane, and the like. Is mentioned. As hydrocarbyloxysilane in which p = in the general formula (4), R ² is methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, hexyl group, octyl group, phenyl group, Examples include trimethoxysilane, triethoxysilane, tripropoxysilane, triisopropoxysilane, tributoxysilane, triisobutoxysilane having a tolyl group, benzyl group, phenylethyl group and the like. Specific examples include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, and octadecyltrimethoxysilane. Examples of the hydrocarbyloxysilane having p = 2 in the general formula (4) include dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldibutoxysilane, methylethyldimethoxysilane, diphenyldimethoxysilane, and diphenyldiethoxysilane. Is mentioned.

  Examples of the hydrocarbyloxysilane represented by the above general formula (4) include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, methyltributoxysilane, methyltriisobutoxysilane, tetra Methoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraisobutoxysilane and the like are preferable.

  The hydrocarbyloxysilane represented by the general formula (3) and the hydrocarbyloxysilane represented by the general formula (4) can each be used as a partial hydrolyzate, and used as a mixture with the partial hydrolyzate. May be. These compounds may also be used as condensates condensed with each other. Furthermore, the hydrocarbyloxysilane represented by the general formula (3) and a partial hydrolyzate thereof, and the hydrocarbyloxysilane and the partial hydrolyzate represented by the general formula (4) are each one kind or plural kinds. It can also be used as a combination.

  In the production method 1, at least one hydrocarbyloxysilane represented by the general formula (2), a partial hydrolyzate thereof, or a combination thereof, which is the component (a), is subjected to hydrolysis and condensation.

  In the production method 2, at least one hydrocarbyloxysilane represented by the general formula (2) which is the component (a), a partial hydrolyzate thereof or a combination thereof, and the general formula (3) which is the component (b) At least one selected from the group consisting of a hydrocarbyloxysilane represented by the formula, a partial hydrolyzate thereof, a hydrocarbyloxysilane represented by the general formula (4), a partial hydrolyzate thereof, and at least one condensate thereof. The seed compound is subjected to partial cohydrolysis and polycondensation.

  In the production method 2, the ratio of the component (a) to the component (b) is not particularly limited. However, if the proportion of the component (a) which is a β-ketoester group-containing organosilicon compound is too small, the resulting β-ketoester group-containing organopolysiloxane compound will hardly exhibit the β-ketoester group-derived characteristics. It must have at least one β-ketoester group therein. Accordingly, the ratio of the component (a) to the component (b) is preferably in the range of 1:99 to 99: 1 in molar ratio in terms of silicon atoms, and more preferably in the range of 10:90 to 80:20. More preferably. There are no particular limitations on the blending order, mixing method, and partial cohydrolysis and polycondensation of the component (a) and component (b).

  In any of the production methods 1 and 2, the hydrolysis / condensation reaction is usually performed on the basis of a conventionally known method, for example, the component (a) alone or the mixture of the component (a) and the component (b). What is necessary is just to perform partial (co) hydrolysis and polycondensation reaction by adding water in the presence of a catalyst. At this time, an appropriate organic solvent can be used as necessary.

  Various conventionally known catalysts can be used as the hydrolysis / condensation reaction catalyst used. Specific examples include organic acids such as acetic acid, trifluoroacetic acid, butyric acid, oxalic acid, maleic acid, citric acid, methanesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, hydrochloric acid, nitric acid, phosphoric acid, sulfuric acid, etc. Inorganic acids; basic compounds such as sodium hydroxide, potassium hydroxide, sodium hydrogen carbonate, sodium carbonate, sodium acetate, potassium acetate, ammonia, ammonium hydroxide, triethylamine; fluorine-containing compounds such as potassium fluoride and ammonium fluoride Compounds; organometallic compounds such as tetraisopropyl titanate, tetrabutyl titanate, dioctyltin dilaurate, and aluminum chelates can be exemplified. The said catalyst may be used individually by 1 type, and may use multiple types together. The amount of the catalyst used is preferably in the range of 0.0001 to 10 mol%, more preferably in the range of 0.001 to 3 mol% with respect to the Si atoms present in the entire raw material. .

  As described above, in the production of the organopolysiloxane compound, the average degree of polymerization is determined by the amount of water used for partial hydrolysis and polycondensation. When water is added in excess, the hydrocarbyloxy group is hydrolyzed, and as a result, a resin having a lot of branched structures is obtained and the desired silicone oligomer containing hydrocarbyloxy group cannot be obtained. Need to be determined strictly. For example, when all the hydrocarbyloxysilane raw materials used are monomers having one silicon atom, in order to prepare an organopolysiloxane compound having an average polymerization degree of Z, (Z-1 ) It is preferable to perform partial hydrolysis and polycondensation using molar water.

  At this time, an organic solvent such as alcohols, ethers, esters, and ketones may be used as necessary. Specific examples of these organic solvents include alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol and propylene glycol monomethyl ether, ethers such as diethyl ether and dipropyl ether, methyl acetate, ethyl acetate and acetoacetic acid. Examples thereof include esters such as ethyl, and ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone. Moreover, you may use together nonpolar solvents, such as hexane, toluene, and xylene, with the said solvent. In particular, it is preferable to use alcohols such as methanol, ethanol and isopropyl alcohol.

  The amount of the organic solvent used may generally be in the range of 0 to 1000 parts by mass with respect to 100 parts by mass in total of the hydrocarbyloxysilane, the partial hydrolyzate thereof, and the condensate thereof. Considering the uniformity of the reaction system at the start of hydrolysis, the effect of addition, and pot yield, the range is preferably 10 to 500 parts by mass, and more preferably 15 to 200 parts by mass.

  As an actual operation in partial (co) hydrolysis and polycondensation reaction, a predetermined amount of water or a mixed solution of water / organic solvent is dropped into a mixed system comprising a hydrocarbyloxysilane raw material, a catalyst and an organic solvent, or hydrocarbyloxy It is preferable to drop a predetermined amount of a mixed solution of water / catalyst or a mixed solution of water / catalyst / organic solvent into a mixed system composed of a silane raw material and an organic solvent. At this time, a hydrocarbyloxysilane raw material having a methoxy group or an ethoxy group having a high hydrolysis reactivity, and a hydrocarbyloxysilane raw material having an alkoxy group having 3 to 4 carbon atoms such as a propoxy group or a butoxy group having a low hydrolysis reactivity It is also possible to carry out the polycondensation reaction after separately hydrolyzing and separately mixing the two components and optionally further carrying out partial cohydrolysis.

  What is necessary is just to implement each reaction in the temperature range of 0-150 degreeC. In general, the reaction proceeds slowly at a temperature lower than room temperature, which is not practical. Even when the temperature is too high, an isomerized group in which a β-ketoester group is enolized reacts with a hydrocarbyloxy group of another molecule, Since cross-linking reaction causes thickening, gelation, thermal decomposition of epoxy groups, mercapto groups, etc. and thermal polymerization of acryloyloxy groups, adverse effects on specific functional groups occur. It is preferable to be in the temperature range. After the reaction, the target organopolysiloxane compound is subjected to a purification step such as neutralization, adsorption, filtration, etc. of the used catalyst and purification by distilling off the used organic solvent and by-product alcohol and low-boiling substances. Can be obtained.

  The adhesive modifier of the component (B) may be contained in an amount of usually 0.001 to 5 parts by mass with respect to 100 parts by mass of the acrylic polymer of the component (A), and further 0.01 to 2 It is preferable to make it contain in the quantity of a mass part. When there are too many adhesive modifiers of (B) component, initial adhesive strength will fall and it will become easy to produce the swelling and peeling of the polarizing plate or the laminated board of a polarizing plate and a phase difference plate in a liquid crystal element use environment. . Also, if the amount of the component (B) is too small, the adhesive strength becomes too high when heated in the manufacturing process and the appropriate peelability is lost. When the polarizing plate or the laminated plate of the polarizing plate and the retardation plate is peeled off from the substrate, the liquid crystal cell is easily damaged, and the adhesive remains on the substrate surface easily.

  In addition, it is preferable to mix | blend the acrylic polymer of (A) component, and the adhesive modifier of (B) component just before use of a composition.

-Other ingredients-
The pressure-sensitive adhesive composition for liquid crystal elements of the present invention contains the above acrylic polymer and a specific adhesive modifier as essential components, but may further contain other components as necessary. .

  Examples of other components that can be blended in the pressure-sensitive adhesive composition for liquid crystal elements of the present invention include tackifiers, plasticizers, cross-linking agents, and dyes. These can be known ones. These optional components can be blended alone or in combination of two or more.

  In the pressure-sensitive adhesive composition for liquid crystal elements of the present invention, it is particularly preferable that a crosslinking agent is blended. Examples of the crosslinking agent used in the present invention include isocyanate compounds, epoxy compounds, amine compounds, metal chelate compounds and aziridine compounds.

  Examples of isocyanate compounds used as crosslinking agents include tolylene diisocyanate, hydrogenated tolylene diisocyanate, tolylene diisocyanate adduct of trimethylolpropane, xylylene diisocyanate adduct of trimethylolpropane, triphenylenemethane triisocyanate, isophorone diisocyanate, and These ketoxime block products or phenol block products can be mentioned.

  Examples of epoxy compounds include bisphenol A, epichlorohydrin type epoxy resins, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl. Ether, trimethylolpropane triglycidyl ether, diglycidylaniline, diglycidylamine, N, N, N ', N'-tetraglycidyl-m-xylenediamine and 1,3-bis (N, N'-diglycidylaminomethyl) ) Cyclohexane and the like.

  Furthermore, examples of amine compounds include hexamethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, amino resin, and melamine resin.

  Still further, examples of the metal chelate compound include compounds in which acetylacetone is coordinated to a polyvalent metal such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, and zirconium, Examples include compounds in which ethyl acetoacetate is coordinated to a metal.

  Further, examples of the aziridine compounds include N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxamide), N, N′-toluene-2,4-bis (1-aziridinecarboxamide), tri Ethylenemelamine, bisisophthaloyl-1- (2-methylaziridine), tri-1-aziridinylphosphine oxide, N, N′-hexamethylene-1,6-bis (1-aziridinecarboxamide), trimethylolpropane -Tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate and the like can be mentioned.

  These crosslinking agents can be used singly or in combination of two or more.

  The cross-linking agent is usually used in an amount of 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the resin component in the composition of the present invention. In addition, since these crosslinking agents have reactivity with the above-mentioned (A) component and (B) component of the present invention, they are packaged separately and used immediately mixed with the (A) component and the (B) component. Is done.

  EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention should not be construed as being limited to these examples.

Analysis of the organopolysiloxane compounds obtained in the following synthesis examples was carried out by the following method.
(1) The average degree of polymerization of the organopolysiloxane compound was calculated from the weight average molecular weight obtained by gel permeation chromatography (GPC) analysis based on a calibration curve created from a polystyrene standard sample.
(2) The structural analysis of the organopolysiloxane compound was performed by infrared absorption spectrum (IR) analysis and proton nuclear magnetic resonance spectrum ( ¹ H-NMR) analysis.

[Synthesis Example 1]
[Synthesis of an organopolysiloxane compound having a structure of a = 1, b = 0, c = 0, and d = 1.33 in the average composition formula (1)]
In a 1 L flask equipped with a stirrer, cooling condenser, thermometer and dropping funnel, the formula:

The acetoacetate functional trimethoxysilane represented by 316.8 g (1.2 mol) and methanol 32 g (1.0 mol) were charged, while stirring the flask at an internal temperature of 20-30 ° C., 18 g (1.0 mol) of 0.05N hydrochloric acid aqueous solution A mixed solution of methanol and 48 g (1.5 mol) of methanol was added dropwise over 30 minutes, and the mixture was further heated and aged for 2 hours under reflux.

Next, 11.2 g (KF: 1.92 × 10 ⁻³ mol) of a 1% by mass methanol solution of potassium fluoride was added, and further aged for 2 hours under reflux to cause partial cohydrolysis and polycondensation reaction. Subsequently, the alcohol component was distilled off while raising the internal temperature to 120 ° C. under normal pressure, followed by filtration to obtain a colorless transparent liquid organopolysiloxane compound (yield: 255 g, yield: 94%).

This organopolysiloxane compound had a viscosity at 25 ° C. of 158 mm ² / s, a specific gravity of 1.200, and a refractive index of 1.4461. When this was subjected to nuclear magnetic resonance spectral analysis, the presence of a β-ketoester group and its enol isomerized group-containing organic group and a methoxy group was confirmed, and the enol isomerized group and the methoxy group were exchanged. It was confirmed that a crosslinked structure was formed.
The weight average molecular weight of this product was 7366.

[Synthesis Example 2]
[Synthesis of an organopolysiloxane compound having a structure of a = 0.5, b = 0, c = 0.5, and d = 1.33 in the average composition formula (1)]
In a 1 L flask equipped with a stirrer, cooling condenser, thermometer and dropping funnel, the formula:

Acetoacetate functional ethoxysilane 306 g (1.0 mol), methyltriethoxysilane 178 g (1.0 mol) and ethanol 45 g (1 mol) were charged, while stirring the flask at an internal temperature of 20-30 ° C., 0.05N hydrochloric acid aqueous solution 30 g A mixed solution of (1.667 mol) and ethanol 45 g (1 mol) was added dropwise over 30 minutes, and the mixture was further heated and aged for 2 hours under reflux.

Next, 11.2 g (KF: 1.92 × 10 ⁻³ mol) of a 1% by mass ethanol solution of potassium fluoride was added, and further aged for 2 hours under reflux to cause partial cohydrolysis and polycondensation reaction. Subsequently, the alcohol component was distilled off while raising the internal temperature to 120 ° C. under normal pressure, followed by filtration to obtain a colorless transparent liquid organopolysiloxane compound (yield: 342 g, yield: 94%).

Nuclear magnetic resonance spectrum analysis of this product confirmed the presence of β-ketoester group and its enol isomerized group-containing organic group, ethoxy group, and methyl group, and the enol isomerized group and alkoxy group were exchanged. It was confirmed that a crosslinked structure was formed.
The weight average molecular weight of this product was 6727.

[Synthesis Example 3]
[Synthesis of an organopolysiloxane compound having a structure of a = 0.5, b = 0, c = 0, and d = 1.83 in the average composition formula (1)]
In a 1 L flask equipped with a stirrer, cooling condenser, thermometer and dropping funnel, the formula:

Acetoacetate functional ethoxysilane 306g (1.0mol), tetraethoxysilane 208g (1.0mol) and ethanol 45g (1.0mol) were charged, while stirring the flask at an internal temperature of 20-30 ° C, 0.05N hydrochloric acid aqueous solution 30g A mixed solution of (1.667 mol) and 45 g (1.0 mol) of ethanol was added dropwise over 30 minutes, and the mixture was further heated and aged for 2 hours under reflux.

Next, 11.2 g (KF: 1.92 × 10 ⁻³ mol) of a 1% by mass ethanol solution of potassium fluoride was added, and further aged for 2 hours under reflux to cause partial cohydrolysis and polycondensation reaction. Subsequently, the alcohol component was distilled off while raising the internal temperature to 120 ° C. under normal pressure, followed by filtration to obtain a colorless transparent liquid organopolysiloxane compound (yield: 342 g, yield: 94%).

When nuclear magnetic resonance spectrum analysis of this product was performed, the presence of β-ketoester group and its enol isomerized group-containing organic group, and ethoxy group was confirmed, and the enol isomerized group and the alkoxy group were exchanged and crosslinked. It was confirmed that a structure was formed.
The weight average molecular weight of this product was 9803.

[Synthesis Example 4]
[Synthesis of organopolysiloxane compound having a structure of a = 0.833, b = 0.167, c = 0, and d = 1.33 in the average composition formula (1)]
The amount of 316.8 g (1.2 mol) of the acetoacetate functional trimethoxysilane used in Synthesis Example 1 was changed to 264.0 g (1.0 mol), and γ-glycol was used as a raw material monomer in addition to the acetoacetate functional trimethoxysilane. A colorless and transparent liquid organopolysiloxane compound was obtained in the same manner as in Synthesis Example 1 except that 47.2 g (0.2 mol) of silyloxypropyltrimethoxysilane was added (yield: 248 g, yield: 93.5%).

The nuclear magnetic resonance spectrum analysis of this product confirmed the presence of β-ketoester group and its enol isomerized group-containing organic group, glycidyl group and methoxy group, and the enol isomerized group and methoxy group exchanged. It was confirmed that a crosslinked structure was formed.
The weight average molecular weight of this product was 10211.

[Synthesis Example 5]
[Synthesis of an organopolysiloxane compound having a structure of a = 1.0, b = 0, c = 0.2, and d = 1.0 in the average composition formula (1)]
The amount of acetoacetate functional trimethoxysilane used in Synthesis Example 1 was changed from 316.8 g (1.2 mol) to 264.0 g (1.0 mol), and the formula:

In the same manner as in Synthesis Example 1, except that 62.0 g (0.25 mol) of an acetoacetate-functional methyldimethoxysilane represented by the following formula was added and the amount of 0.05N hydrochloric acid aqueous solution was changed to 20.25 g (1.125 g): A colorless transparent liquid organopolysiloxane compound was obtained (yield: 259 g, yield: 94.4%).

Nuclear magnetic resonance spectrum analysis of this product confirmed the presence of β-ketoester group and its enol isomerized group-containing organic group, methyl group and methoxy group, and exchange of enol isomerized group and methoxy group. It was confirmed that they reacted to form a crosslinked structure.
The weight average molecular weight of this product was 8211.

[Example 1]
n-butyl acrylate 43 parts by mass, ethyl acrylate 20 parts by mass, 2-ethylhexyl acrylate 25 parts by mass, styrene 3 parts by mass, acrylic acid 7 parts by mass, 2-hydroxyethyl acrylate 2 parts by mass, ethyl acetate 100 parts by mass and After 0.2 parts by mass of azobisisobutyronitrile was put into a reactor and the inside of the reactor was replaced with nitrogen gas, the mixture was reacted at 63 ° C. for 2 hours in a nitrogen atmosphere with stirring. Furthermore, 10 parts by mass of a solution prepared by dissolving 0.05 part by mass of azobisisobutyronitrile in 10 parts by mass of ethyl acetate prepared separately was added dropwise to the reactor at 63 ° C. over 2 hours.
Next, the temperature of the reactor was raised to 72 ° C., 10 parts by mass of an ethyl acetate solution of azobisisobutyronitrile prepared in the same manner as above was dropped over 4 hours, and 220 parts by mass of an ethyl acetate solution of an acrylic polymer was added. Got. The concentration of the acrylic polymer in the ethyl acetate solution is 45% by mass.
0.2 parts by mass of the β-ketoester group-containing organopolysiloxane composition synthesized in Synthesis Example 1 in 220 parts by mass of the reaction liquid (corresponding to 100 parts by mass of the acrylic polymer), and a polyisocyanate compound (commercial product) Name: Coronate L, 2 parts by mass of Nippon Polyurethane Co., Ltd.) was added and stirred well to obtain the adhesive composition of the present invention.

= Evaluation as an adhesive =
The peelability and mountability were measured and evaluated as follows.

・ Peelability ・ ・ Measurement of initial adhesive strength:
The adhesive composition obtained as described above was applied to a polyester release film and then dried to form a coating having a thickness of 25 μm after drying. Subsequently, the coating of the adhesive composition on the release film was transferred onto one side of a 0.20 mm thick polarizing plate and aged for 7 days under conditions of a temperature of 23 ° C. and a humidity of 65%. Then, the film side of the adhesive composition of this polarizing plate was stuck on the surface of the glass substrate, and the sample was produced. This sample was bonded by holding for 20 minutes at a temperature of 50 ° C. and a pressure of 5 kg / cm ² .

  With respect to the adhesive force between the polarizing plate and the glass substrate thus bonded, the initial adhesive strength (adhesive strength after standing at 23 ° C. for 1 hour) was measured according to JIS-Z-0237 and JIS-Z-0238.

..Measurement of adhesive strength after heat aging:
A sample prepared in the same manner as described above was allowed to stand at 80 ° C. for 15 hours, then allowed to cool to 23 ° C., left at this temperature for 1 hour, and then the adhesive strength was measured in the same manner as described above.

.. Evaluation of remaining glue:
In the measurement of the adhesive strength at the initial stage and after heat aging as described above, when the polarizing plate is peeled off from the glass substrate, whether or not the adhesive remains on the glass substrate surface (residue residue) is visually observed and evaluated. did.

・ Mountability A sample prepared in the same manner as above was cut to a size of 20 × 30 cm ² , and bonded under the above conditions, and then 100 ° C., 800 hours under drying, and 60 ° C., 90% RH. Then, the film was allowed to stand for 800 hours, and the presence or absence of foaming in the adhesive composition film and the occurrence of peeling between the polarizing plate and the substrate were visually observed and evaluated.

These results are shown in Table 1. In this example, the liquid crystal element in which the polarizing plate was bonded to the substrate surface exhibited good characteristics.
[Example 2]
Example 1 was the same as Example 1 except that the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 2 was used instead of the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 1. Thus, an adhesive composition was obtained. The properties of the adhesive composition were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 3
Example 1 was the same as Example 1 except that the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 1 was used instead of the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 1. Thus, an adhesive composition was obtained. The properties of the adhesive composition were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 4
Example 1 was the same as Example 1 except that the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 4 was used instead of the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 1. Thus, an adhesive composition was obtained. The properties of the adhesive composition were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 5
In Example 1, instead of the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 1, the same procedure as in Example 1 was used except that the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 5 was used. Thus, an adhesive composition was obtained. The properties of the adhesive composition were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 1]
An adhesive composition was obtained in the same manner as in Example 1 except that the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 1 was not used. The properties of the adhesive composition were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 2]
In Example 1, instead of the β-ketoester group-containing organopolysiloxane compound synthesized in Synthesis Example 1,

An adhesive composition was obtained in the same manner as in Example 1 except that 0.2 parts by mass of the β-ketoester group-containing alkoxysilane represented by the formula (1) was used. The properties of the adhesive composition were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Claims (2)

(A) an acrylic polymer;
(B) The following average composition formula (1):
Y _a R ¹ _b R ² _c Si (OR ³ ) _d (OH) _e O _{(4-abbcde) / 2}
... (1)
(Where
Y is an organic group containing a β-ketoester group which may be at least partially enolized,
R ¹ is a hydrocarbyl in which a mercapto group, an epoxy group, an acryloyloxy group, a methacryloyloxy group, an alkenyl group, an amino group, a halogen atom, and an enolized β-ketoester group are represented by the formula OR ³ in or between molecules. A monovalent hydrocarbon group having 1 to 18 carbon atoms, which contains or does not contain at least one functional group selected from the group consisting of groups formed by reaction with an oxy group,
R ² does not contain a functional group and is a monovalent hydrocarbon group having 1 to 18 carbon atoms different from R ¹ ;
R ³ is a monovalent hydrocarbon group having 1 to 4 carbon atoms,
a, b, c, d, and e are numbers represented by 0.01 ≦ a ≦ 1, 0 ≦ b <1, 0 ≦ c ≦ 2, 0 ≦ d ≦ 2, and 0 ≦ e ≦ 1, respectively. And 2 ≦ a + b + c + d + e ≦ 3. )
An adhesive modifier comprising an organopolysiloxane compound containing a β-ketoester group-containing organic group and a hydrocarbyloxy group in one molecule;
A pressure-sensitive adhesive composition for liquid crystal elements in which the adhesive modifier of component (B) is in the proportion of 0.001 to 10 parts by mass with respect to 100 parts by mass of the acrylic polymer of component (A). .   The acrylic polymer of the component (A) is 60 to 99% by mass of an acrylic monomer having no functional group, 1 to 20% by mass of an acrylic monomer having a functional group, and other monomers copolymerizable with these monomers. The pressure-sensitive adhesive composition for liquid crystal elements according to claim 1, which is a copolymer comprising 0 to 20% by mass (100% by mass of these three types of monomers).