KR102391158B1 - Organopolysiloxane compound containing isocyanate group, method for producing the same, adhesive, tackifier and coating composition - Google Patents

Abstract

In the present invention, a corresponding isocyanate group-containing organopolysiloxane compound is obtained by ene-thiol addition reaction of an organopolysiloxane compound having a mercapto group and an isocyanate compound having a polymerizable group. It is a high molecular compound having an isocyanate group, and while having reactivity with an inorganic material, film-forming property due to the polymer is expressed. By applying the same reaction, introducing another functional group, specifically, introducing a polyether group or a β-ketoester group, when used as an adhesion modifier for liquid crystal pressure-sensitive adhesives, initial reworkability and high adhesion under high temperature or high temperature and humidity can be compatible adhesive is obtained.

Description

Isocyanate group-containing organopolysiloxane compound, manufacturing method thereof, adhesive, adhesive and coating agent

The present invention relates to a novel organopolysiloxane compound containing an isocyanate group-containing organic group and a method for preparing the same. More specifically, it is an organopolysiloxane compound containing an isocyanate group-containing organic group, preferably a hydrocarbyloxy group, in one molecule of which a sulfur atom is necessarily included in the linkage of the isocyanate group and the hydrolyzable silyl group, and a monomer used in the prior art Compared with the silane coupling agent of the type silane coupling agent, film-forming property due to being an oligomer, low volatility, hydrophobicity increase due to sulfur-containing linkage structure, and the proportion of organic moieties increases, compatibility with resin is improved, Since the bonding strength and interaction with the matrix resin having a hydroxyl group are excellent, the effect of remarkably improving the adhesion between the pressure-sensitive adhesive containing the matrix resin and the substrate is achieved. Further, the present invention relates to an adhesive, a pressure-sensitive adhesive and a coating agent using the organopolysiloxane compound, and also to articles such as a pressure-sensitive adhesive polarizing plate and a liquid crystal display device.

A silane coupling agent has two or more different functional groups in a molecule|numerator, and acts as an intermediate|middle station which connects the organic material and inorganic material which normally are difficult to couple|bond. One of the functional groups is a hydrolyzable silyl group, a silanol group is generated by the presence of water, and the silanol group reacts with a hydroxyl group on the surface of the inorganic material to form a chemical bond with the surface of the inorganic material. In addition, other functional groups are organic reactive groups, such as a vinyl group, an epoxy group, an amino group, a (meth)acryl group, a mercapto group, and an isocyanate group, which form a chemical bond with organic materials, such as various synthetic resins. Using these characteristics, it is widely used as a modifier for organic/inorganic resins, adhesion aids, various additives, and the like.

Among the silane coupling agents, those having an isocyanate group have excellent reactivity with active hydrogen structural groups such as primary and secondary hydroxyl groups and amino groups and carboxylic acid groups. It is useful as a modifier.

On the other hand, since the silane coupling agent has a low molecular weight, the active ingredient is reduced from the treated surface due to volatilization after application, and generation of an alcohol component due to hydrolysis of the silyl group may be a problem. As an improvement of this point, the organopolysiloxane compound which has a hydrocarbyloxy group which is a partial hydrolysis-condensation product of a silane coupling agent is mentioned. On the other hand, this organopolysiloxane compound is also called a silicon alkoxy oligomer.

As described above, the silicon alkoxy oligomer is generally synthesized by a hydrolysis condensation reaction, but when the reactive organic functional group to be introduced has hydrolysability, the present manufacturing method cannot be applied. Therefore, as a method of introducing a reactive organic group having hydrolysis property such as an acid anhydride group or an isocyanate group, a hydrosilylation reaction of a hydrosilyl group and an unsaturated double bond structural group is exemplified. Japanese Unexamined Patent Publication No. 2013-129691, Japan In Patent Laid-Open No. 2013-129809 (Patent Documents 1 and 2), an acid anhydride group-containing organopolysiloxane by hydrosilylation is disclosed.

However, in the case of an isocyanate group, allyl isocyanate, which is a representative industrial product of polymerizable group-containing isocyanate, has high toxicity, is a nitrogen-containing compound, and is an addition poison to the platinum complex, which is a hydrosilylation reaction catalyst. can be said to be unrealistic.

In addition, even by reacting 1 mole of an industrially available diisocyanate compound per mole of the functional group of the organopolysiloxane having an active hydrogen-containing structural group such as an amino group or a mercapto group, an organopolysiloxane compound in which unreacted isocyanate groups remain can be obtained. However, in this case, since there is no selectivity in the reactivity of the isocyanate and the active hydrogen-containing structural group, the raw material diisocyanate behaves as a crosslinking agent, resulting in unnecessary high molecular weight and gelation of the organopolysiloxane compound. In addition, since a side reaction occurs in which the NH structure of the urea bond and thiourethane bond produced by the reaction and the remaining isocyanate react, a problem remains in ensuring stability of the resulting reactant.

By the way, the use as an adhesive modifier of an adhesive is also a typical example of a silane coupling agent, For example, the adhesive at the time of affixing a liquid crystal cell and an optical film is accompanied with enlargement and widening of the size of a liquid crystal display device (LCD), The required adhesive performance is high. In the case of LCD, contrary to the initial expectation that it would be difficult to enlarge it to 20 inches or more, it is rapidly increasing in size. Major manufacturers have been focusing on the production of small panels of 20 inches or less so far, but according to the recent trend, they are actively introducing the latest technology and expanding their product range to large sizes of 20 inches or more.

In this way, in all kinds of optical films, the glass used at the time of manufacturing the liquid crystal panel tends to be enlarged. However, when a defective product is generated at the time of initial adhesion, the optical film is removed from the liquid crystal cell, and the liquid crystal cell is washed and then reused. Not only is it difficult to remove an optical film by strong adhesive force, but since there is a large possibility of destroying an expensive liquid crystal cell, as a result, the production cost is greatly increased.

Accordingly, with the increase in LCD size, attempts are being made to develop a high-functional pressure-sensitive adhesive that is compatible with various adhesive properties such as adhesiveness and reworkability. For example, in Japanese Patent No. 3022993 and Japanese Patent No. 5595034 (Patent Documents 3 and 4), for the purpose of providing a polarizing plate having excellent durability in an environment of high temperature and high humidity, an acrylic containing epoxy silane and isocyanate silane A pressure-sensitive adhesive composition has been proposed.

Moreover, in Unexamined-Japanese-Patent No. 2014-152321 and Unexamined-Japanese-Patent No. 2013-79320 (patent document 5, 6), initial adhesive force is low, and it is excellent in rework property, and adhesive force under high temperature and humidity after sticking. An acrylic pressure-sensitive adhesive comprising an organopolysiloxane compound having a hydrocarbyloxy group having a polyether group, an epoxy group or an acid anhydride group has been proposed as an adhesive having improved durability and excellent long-term durability.

By containing such a silane compound, the substrate and the polarizing plate can maintain an appropriate adhesive strength at a level required in the environment in which they are actually used, and the adhesive strength does not increase excessively by heating, etc., without damaging the liquid crystal element, It has become possible to peel a polarizing plate easily.

Moreover, as a recent technological trend, with the spread of touch sensor LCD, the design in which an adhesive layer and the transparent electrode layer represented by indium tin oxide (ITO) make direct contact is mainstream. In such product design, since there is concern about corrosion of ITO if it is a carboxylic acid group-containing acrylic polymer base, which has been the mainstream as an adhesive, the technology is generally shifting to a pressure-sensitive adhesive composition based on an OH group-containing acrylic polymer as a base.

However, in such an acid-free pressure-sensitive adhesive having a base polymer composition, a silane coupling agent effective as a conventional pressure-sensitive adhesive has limited effects, and a silane coupling agent that contributes to the expression of performance at the same level or higher has not been found. Among them, a silane coupling agent having an isocyanate group is one of the promising candidates.

From the above, a simple and versatile manufacturing method for providing an organopolysiloxane compound having an isocyanate group and the compound is desired, and in the use of an isocyanate group-containing organopolysiloxane compound having a hydrocarbyloxy group, initial Development of a balanced acid-free base polymer type pressure-sensitive adhesive that maintains workability and high adhesive strength under high temperature and humidity has been desired.

Japanese Patent Laid-Open No. 2013-129691 Japanese Patent Laid-Open No. 2013-129809 Japanese Patent No. 3022993 Japanese Patent No. 5595034 Publication Japanese Patent Laid-Open No. 2014-152321 Japanese Patent Laid-Open No. 2013-79320

The present invention has been made in view of the above circumstances, and is a simple and versatile method for producing an organopolysiloxane compound containing an isocyanate group-containing organic group, an isocyanate group-containing organopolysiloxane compound obtained thereby, an adhesive using the compound, an adhesive and It aims to provide a coating agent. Moreover, it is another object to provide various articles|goods, such as glass fiber products, an adhesive polarizing plate, and a liquid crystal display device.

The pressure-sensitive adhesive containing the organopolysiloxane compound as a silane coupling agent has a low initial adhesive force and excellent reworkability when affixed without corrosion of an easily corrosive adherend such as ITO, and has been subjected to high temperature or high temperature and humidity treatment after affixing. After that, the adhesive force with the adherend increases, and it becomes possible to provide an adhesive layer excellent in long-term durability.

As a result of repeated intensive studies to achieve the above object, the present inventors have produced an organopolysiloxane compound having a corresponding isocyanate group by ene-thiol addition reaction of an organopolysiloxane compound having a mercapto group and an isocyanate compound having a polymerizable group. found to be obtained. The compound has excellent bonding strength and interaction with the matrix resin having a hydroxyl group. In addition, the organopolysiloxane compound having an isocyanate group and a hydrocarbyloxy group having a polyether group introduced therein, found that an adhesive capable of achieving both initial reworkability and high adhesive strength under high temperature or high temperature and humidity was obtained, thereby achieving the present invention reached

Accordingly, the present invention provides the following organopolysiloxane compound, a method for producing the same, an adhesive, a pressure-sensitive adhesive, a coating agent, and various articles.

[1] The following average composition formula (1)

Y _a R ¹ _b R ² _c Si(OR ³ ) _d (OH) _e O _(4-abcde)/2 … (One)

(Wherein, Y is an organic group containing a thioether linking group and an isocyanate group, and R ¹ is at least one selected from the group consisting of a mercapto group, an epoxy group, a halogen atom, a β-ketoester group, a polyether group and a thioether group. A monovalent hydrocarbon group having 1 to 18 carbon atoms with or without a functional group, R ² is a monovalent hydrocarbon group having 1 to 18 carbon atoms that does not include a functional group and is different from R ¹ , R ³ is a monovalent hydrocarbon group having 1 to 4 carbon atoms, a, b, c, d, and e are each 0.01≤a≤1, 0≤b<1, 0≤c≤2, 0≤d≤2 and 0≤e≤1, and 2≤a+b+c+d+e≤3).

[2] The organopolysiloxane compound according to [1], wherein b is 0.

[3] The organopolysiloxane compound according to [1], wherein R ¹ contains a thioether linking group and a polyether group as functional groups.

[4] The organopolysiloxane compound according to [1], wherein R ¹ contains a thioether linking group and a β-ketoester group as functional groups.

[5] A method for producing an organopolysiloxane compound containing an isocyanate group-containing organic group according to any one of [1] to [4],

(i) an organopolysiloxane compound containing a mercapto group-containing organic group represented by the following general formula (2);

B _a R ¹ _b R ² _c Si(OR ³ ) _d (OH) _e O _(4-abcde)/2 … (2)

(Wherein, B is an organic group containing a mercapto group, R ¹ , R ² , R ³ , a, b, c, d and e have the same meaning as above, and 2≤a+b+c+d+ satisfies e≤3)

(ii) an unsaturated double bond-containing isocyanate compound represented by the following general formula (3)

(wherein Z is a monovalent hydrocarbon group having 2 to 10 carbon atoms which may include an unsaturated double bond and may have an ester bond interposed therebetween)

A method for producing an organopolysiloxane compound containing an isocyanate group-containing organic group, characterized in that the ene-thiol addition reaction is carried out in the presence of a radical generator.

[6] An adhesive comprising an organopolysiloxane compound containing an isocyanate group-containing organic group according to any one of [1] to [4].

[7] An adhesive comprising an organopolysiloxane compound containing an isocyanate group-containing organic group according to any one of [1] to [4],

(A) 100 parts by mass of alcoholic hydroxyl group-containing acrylic polymer

(B) 0.001 to 10 parts by mass of the organopolysiloxane compound containing the isocyanate group-containing organic group

(C) 0.01-10 mass parts of polyfunctional crosslinking agent

Adhesive, characterized in that it contains.

[8] A coating agent comprising an organopolysiloxane compound containing an isocyanate group-containing organic group according to any one of [1] to [4].

[9] An article coated or surface-treated with the coating agent according to [8].

[10] The article according to [9], wherein the substrate to be coated or surface treated with the coating agent is a glass fiber product selected from glass cloth, glass tape, glass mat, and glass paper.

[11] The article according to [9], wherein the substrate to be coated or surface-treated with the coating agent is an inorganic filler.

[12] The article according to [9], wherein the substrate to be coated or surface-treated with the coating agent is ceramic or metal.

[13] A polarizing film and a pressure-sensitive adhesive polarizing plate comprising a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive according to [7] on one or both surfaces of the polarizing film.

[14] A liquid crystal display device comprising: a liquid crystal cell in which a liquid crystal is sealed between a pair of glass substrates; and a liquid crystal panel having the adhesive polarizing plate according to [13] adhered to one or both surfaces of the liquid crystal cell .

In this invention, an isocyanate group containing organopolysiloxane compound can be obtained conveniently, using an easily available existing industrial raw material. The obtained organopolysiloxane compound is a low-volatile polymer material having an isocyanate group and preferably a hydrolyzable silyl group. Moreover, by mix|blending the compound which has a polyether group as an essential component of an adhesion modifier in an adhesive use, initial stage rework property and high adhesive force under high temperature or high temperature and humidity can be compatible.

1 is a diagram showing an IR spectrum of the reaction product of Example 1. FIG.
2 is a diagram showing a ¹ H-NMR spectrum of the reaction product of Example 1. FIG.
3 is a diagram showing an IR spectrum of the reaction product of Example 7. FIG.
4 is a diagram showing a ¹ H-NMR spectrum of the reaction product of Example 7. FIG.

Hereinafter, the present invention will be specifically described. In addition, in this invention, "organosilicon compound" is contained in "organopolysiloxane compound".

The organopolysiloxane compound of the present invention has the following average composition formula (1)

Y _a R ¹ _b R ² _c Si(OR ³ ) _d (OH) _e O _(4-abcde)/2 … (One)

is displayed as The organopolysiloxane compound is a compound containing, as a reactive group, an isocyanate group and preferably a hydrocarbyloxy group in one molecule.

In the formula (1), Y represents a thioether linkage group and an isocyanate group-containing organic group, for example, the general formula: (2)

-Q-NCO… (2)

(wherein Q is a divalent hydrocarbon group which necessarily includes a sulfur atom in the linkage and may interpose an ester bond).

Here, as Q, in more detail, the following general formula (3)

(wherein A is a divalent hydrocarbon group having 1 to 10 carbon atoms)

or the following general formula (4)

(wherein A has the same definitions as above, and X is a hydrogen atom or a methyl group).

Moreover, in the case of said Formula (4), it is preferable from a viewpoint of the production efficiency at the time of manufacture mentioned later that X is a hydrogen atom.

Specific examples of the divalent hydrocarbon group having 1 to 10 carbon atoms in A include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, and a decylene group. and alkylene groups such as these, and may be any one of chain, branched, and cyclic. A propylene group, a hexylene group, and an octylene group are preferable, and a propylene group is more preferable because it is easy to obtain the mercapto group-containing organopolysiloxane compound used as a reaction raw material to be described later.

R ¹ is a monovalent hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms, and in some cases at least one kind of mercapto group, epoxy group, halogen atom, β-ketoester group, polyether group and thio It may be substituted with a specific functional group selected from an ether group. Examples of the monovalent hydrocarbon group having 1 to 18 carbon atoms include an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, a hexyl group, and an octyl group, a phenyl group, etc. Aralkyl groups, such as an aryl group, a benzyl group, and a phenylethyl group, etc. are mentioned. In particular, a propyl group is preferable. When only the characteristics of the isocyanate group-containing organic group (Y) are expected in the organopolysiloxane compound used in the present invention, a specific functional group may not be included. However, in the case where other properties are provided in addition to the properties of the isocyanate group-containing organic group, the specific functional group may be included in the molecule. The specific functional group is selected according to the properties to be imparted to the organopolysiloxane compound in question. In particular, it is preferable to include an epoxy group and/or a β-ketoester group and/or a polyether group.

R ² does not contain a functional group and is a monovalent hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms, different from R ¹ . For example, an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, a hexyl group, an octyl group, a decyl group, an octadecyl group, an aryl group such as a phenyl group, and benzyl Aralkyl groups, such as group and a phenylethyl group, etc. are mentioned. In particular, a methyl group is preferable.

R ³ represents a monovalent hydrocarbon group having 1 to 4 carbon atoms, and examples thereof include an alkyl group 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 especially preferable.

a, b, c, d and e are the 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 showing the ratio of the number of isocyanate groups-containing organic groups (Y) to the number of silicon atoms in the organopolysiloxane compound. When this a is less than 0.01, the characteristic by the reactivity of the isocyanate group containing organic group desired at the time of use of this organopolysiloxane compound is not exhibited. On the other hand, making a larger than 1 is difficult in terms of 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.

In addition, b is a numerical value indicating the ratio of the number of monovalent hydrocarbon groups (R ¹ ) having 1 to 18 carbon atoms that may contain a specific functional group to the number of silicon atoms in the organopolysiloxane compound, and this is 0 Alternatively, when it is relatively small, the content of hydrocarbyloxy groups (OR ³ ) such as an alkoxy group is relatively increased, so that a hydrolysis reaction or a silylation reaction occurs easily, and in some cases, the affinity of the organopolysiloxane compound to water This is improved. On the other hand, when b is relatively large, when R ¹ has the above specific functional group, the reactivity with organic resins such as epoxy resins, urethane resins, polyamide resins, polyimide resins, polyester resins, and acrylic resins is improved, In addition, when it does not have the said specific functional group, hydrophobicity is provided to the said organopolysiloxane compound depending on the kind of the said monovalent hydrocarbon group (R ¹ ) (when R ¹ is, for example, an alkyl group), and also said organopolysiloxane Effects such as improved affinity or compatibility of the compound with an organic compound or organic resin (when R ¹ is, for example, a phenyl group) are exhibited. In this case, since content of hydrocarbyloxy groups, such as an alkoxy group, is relatively reduced, the reactivity of a hydrocarbyloxysilyl group etc. falls. 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 compound, preferably within the range of 0≤b≤0.8, more preferably 0≤b≤0.5 is the range of

c is a numerical value indicating the ratio of the number of monovalent hydrocarbon groups (R ² ) having 1 to 18 carbon atoms different from R ¹ without including a functional group 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 occurs easily, and in some cases, the water of the organopolysiloxane compound affinity is improved. On the other hand, when this c is relatively large, effects such as providing hydrophobicity to the organopolysiloxane compound or imparting flexibility and releasability to the cured product of the organopolysiloxane compound are obtained. However, in this case, when the content of the hydrocarbyloxy group is relatively decreased, the reactivity of the hydrocarbyloxysilyl group or the like decreases. Therefore, it is necessary to select the value of c within the range of 0≤c<2 according to the purpose of use, preferably 0≤c≤1, and more preferably 0≤c≤0.8.

d is a numerical value indicating the ratio of the number of hydrocarbyloxy groups (OR ³ ) to the number of silicon atoms in the organopolysiloxane compound, 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 compound to the inorganic material is low, and when it is close to 2, the reactivity to the inorganic material is increased on the contrary. Preferably, it is in the range of 0≤d≤1.8, more preferably d>0, still more preferably 1≤d≤1.6.

e is a numerical value indicating the ratio of the number of hydroxyl groups (OH) to the number of silicon atoms, in other words, the content of silanol groups in the organopolysiloxane compound. This silanol group can participate in a silylation reaction or a condensation reaction, and has an effect|action which provides hydrophilicity to the said organopolysiloxane compound. However, it is preferable to make it as small as possible from a viewpoint of maintaining the storage stability of this organopolysiloxane compound favorably. Therefore, it is necessary to set it as the range of 0≤e≤1, preferably the range of 0≤e≤0.5, and more preferably the range of 0≤e≤0.2.

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

In addition, each molecular polymerization degree of this organopolysiloxane compound can be made into the range of 2-100. That is, there may be a dimer of two silicon atoms to a polymer having about a hundred silicon atoms. However, when the average degree of polymerization is 2, the monomer content in the organopolysiloxane compound is high, and the original purpose of use (ie, low volatility) of the silicone oligomer is impaired. On the other hand, when the average degree of polymerization is too large, the organopolysiloxane compound becomes a high viscosity state, a paste form, or a solid state, and handling becomes difficult. Therefore, it is preferable to make average degree of polymerization into the range of 3-100, Furthermore, it is more preferable to set it as the range of 3-50, especially 6-20. From this viewpoint, the numerical value of (a+b+c+d+e) described above is preferably in the range of 2.02≤a+b+c+d+e≤2.67, more preferably 2.04≤a+b+ c+d+e≤2.67. In addition, an average degree of polymerization can be calculated|required as a weight average degree of polymerization in terms of polystyrene by gel permeation chromatography (GPC).

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

The organopolysiloxane compound containing an isocyanate group-containing organic group of the present invention,

(i) an organopolysiloxane compound containing a mercapto group-containing organic group and preferably a hydrocarbyloxy group in one molecule represented by the following general formula (2);

B _a R ¹ _b R ² _c Si(OR ³ ) _d (OH) _e O _(4-abcde)/2 … (2)

(Wherein, B is an organic group containing a mercapto group, R ¹ , R ² , R ³ , a, b, c, d and e have the same meaning as above, and 2≤a+b+c+d+ satisfies e≤3)

(ii) an unsaturated double bond-containing isocyanate compound represented by the following general formula (3)

(wherein Z is a monovalent hydrocarbon group having 2 to 10 carbon atoms which may include an unsaturated double bond and may have an ester bond interposed therebetween)

It is synthesized by ene-thiol addition reaction in the presence of a radical generator.

More specifically, by the following reaction formula, a mercapto group and a carbon-carbon double bond are addition-reacted and a thioether bond is formed, whereby an isocyanate structure and an organo containing a hydrolyzable silyl group in the case of d>0 A polysiloxane compound is obtained.

In the mercapto group-containing organopolysiloxane compound of Formula (2) used in this reaction, R ¹ , R ² , R ³ , a, b, c, d, e are the same as described above, and B is a mercaptomethyl group , a mercaptopropyl group, a mercaptooctyl group, and the like, but a mercaptopropyl group is preferable from the viewpoint of easy availability of industrial raw materials.

The isocyanate compound containing the unsaturated hydrocarbon double bond structural group of Formula (3) used for this reaction is allyl isocyanate, 2-isocyanatoethyl acrylate, 2-isocyanatoethyl methacrylate etc. as an easily available thing. Among them, 2-isocyanatoethyl acrylate and 2-isocyanatoethyl methacrylate, which are low-toxic and easy to handle from the viewpoint of toxicity, are mentioned, and more preferably 2 is rich in ene-thiol reactivity. -Isocyanatoethyl acrylate is used.

The reaction ratio of the mercapto group-containing organopolysiloxane compound and the isocyanate compound containing an unsaturated hydrocarbon double bond structural group is 0.9 to 1.1 of the mercapto group-containing organopolysiloxane compound with respect to 1 mole of the isocyanate compound containing an unsaturated hydrocarbon double bond structural group It is preferable to react in a mole, particularly 0.95 to 1.05 mole.

As a radical generator used for this reaction, a thermal radical generator and an optical radical generator are mentioned, Preferably they are thermal radical generators, such as an azo compound and a peroxide.

Examples of the thermal radical generator include dialkyl peroxides (di-t-butyl peroxide, dicumyl peroxide, etc.), diacyl peroxides [dialkanoyl peroxide (lauroyl peroxide, etc.), diaroyl peroxide Seeds (benzoyl peroxide, benzoyl toluyl peroxide, toluyl peroxide, etc.)], peracid esters [peracetic acid t-butyl, t-butylperoxyoctoate, t-butylperoxybenzoate, etc.) acid alkyl esters], organic peroxides such as ketone peroxides, peroxycarbonates and peroxyketals; Azonitrile compound [2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-methylbutyronitrile) ), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), etc.], azoamide compound {2,2'-azobis {2-methyl-N- [1,1- bis(hydroxymethyl)-2-hydroxyethyl]propionamide}, etc.}, azoamidine compound {2,2'-azobis(2-amidinopropane)dihydrochloride, 2,2'-azobis[2] -(2-imidazolin-2-yl)propane]dihydrochloride etc.}, azoalkane compound [2,2'-azobis(2,4,4-trimethylpentane), 4,4'-azobis(4) -cyanopentanoic acid) and the like] and azo compounds having an oxime skeleton [2,2'-azobis(2-methylpropionamide oxime) and the like]. A thermal radical generating agent can also be used individually or in combination of 2 or more types.

As an optical radical generating agent, For example, benzoin (benzoin alkyl ethers, such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, etc.); Acetophenones (acetophenone, p-dimethylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl acetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-phenyl-2-hydroxy-acetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, etc.); propiophenones (p-dimethylaminopropiophenone, 2-hydroxy-2-methyl-propiophenone, 2,2-dimethoxy-1,2-diphenylethan-1-one, etc.); Butyrylphenones [1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-2-methyl-1-phenyl- propan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methyl-propan-1-one, etc.]; Aminoacetophenones [2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino propane-1 -one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-dimethylamino-2-methyl-1-phenylpropan-1-one, 2-di Ethylamino-2-methyl-1-phenylpropan-1-one, 2-methyl-2-morpholino-1-phenylpropan-1-one, 2-dimethylamino-2-methyl-1-(4-methylphenyl )propan-1-one, 1-(4-butylphenyl)-2-dimethylamino-2-methylpropan-1-one, 2-dimethylamino-1-(4-methoxyphenyl)-2-methylpropane- 1-one, 2-dimethylamino-2-methyl-1-(4-methylthiophenyl)propan-1-one, 2-benzyl-2-dimethylamino-1-(4-dimethylaminophenyl)-butane-1 -on, etc.]; N,N'-dialkylaminobenzos such as benzophenones (benzophenone, benzyl, N,N'-bis(dimethylamino)benzophenone (Michler's ketone) and 3,3-dimethyl-4-methoxybenzophenone) phenone, etc.); ketals (acetophenone dimethyl ketal, benzyl dimethyl ketal, etc.); thioxanthenes (thioxanthene, 2-chlorothioxanthene, 2,4-diethylthioxanthene, etc.); anthraquinones (2-ethylanthraquinone, 1-chloroanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone, etc.); (thio)xanthone (thioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone, etc.); Acridines (1,3-bis-(9-acridinyl)propane, 1,7-bis-(9-acridinyl)heptane, 1,5-bis-(9-acridinyl)pentane, etc.) ; Triazines (2,4,6-tris(trichloromethyl)-s-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2,4 -bis-trichloromethyl-6-(3-bromo-4-methoxy)styrylphenyl-s-triazine, etc.); sulfides (such as benzyldiphenyl sulfide); acylphosphine oxides (such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide); titanocenes; Oxime esters etc. can be illustrated. These photo-radical generators can be used individually or in combination of 2 or more types.

The amount of the radical generator to be used is 0.01 to 15 parts by mass, preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the total amount of the mercapto group-containing organopolysiloxane compound and the unsaturated hydrocarbon double bond structural group-containing isocyanate compound. can

As for reaction temperature, 25-120 degreeC is preferable, More preferably, it is 60-100 degreeC. When it is lower than 25 degreeC, the reaction rate may become low, and when it is higher than 120 degreeC, side reactions, such as superposition|polymerization of olefin compounds, may generate|occur|produce. In addition, although the reaction time in particular is not restrict|limited, Usually, it is 10 minutes - 24 hours.

This reaction is characterized in that the mercapto group-containing organopolysiloxane compound and the isocyanate compound containing an unsaturated hydrocarbon double bond structural group are added dropwise in the presence of a radical generator to react. If the raw materials for the input and the dropping are reversed, homopolymerization of the isocyanate compound containing an unsaturated hydrocarbon double bond structural group will only occur, and the desired compound will not be obtained.

A solvent may be used for the reaction, and any solvent may be used as long as it does not react with a mercapto group, an isocyanate group, and an unsaturated carbon-carbon double bond. Specific examples include hydrocarbon solvents, aromatic solvents, ketone solvents, ester solvents, and ether solvents. More specifically, hydrocarbon solvents include pentane, hexane, heptane, octane, decane, cyclohexane, etc.; Benzene, toluene, and xylene as an aromatic solvent, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc. as a ketone solvent, ethyl acetate, butyl acetate, lactone, etc. as an ester solvent, diethyl as an ether solvent Ether, dibutyl ether, cyclopentyl methyl ether, tetrahydrofuran, 1, 4- dioxane, etc. are mentioned. Among these, toluene, xylene, etc. which are industrially easy to obtain are preferable.

When using the isocyanate group containing organopolysiloxane compound of this invention as a coating agent and a primer, you may contain a solvent as needed. In this case, it is preferable that content of the said isocyanate group containing organopolysiloxane compound is 0.1-90 mass % of the whole, and it is especially 1-50 mass %, and a remainder is a solvent as said arbitrary component. As a solvent, if it is the same thing as the reaction solvent mentioned above, it does not matter.

As the substrate to be coated and treated, it is generally applicable as long as it is an inorganic material that reacts with a hydrolyzable silyl group to form a bond and an organic resin that reacts and bonds with an isocyanate group, and the shape of the substrate is not particularly specified. Among them, examples of typical inorganic materials include inorganic fillers such as silica, glass cloths including glass fibers, glass fiber products such as glass tapes, glass mats and glass papers, ceramics, and metal substrates. Moreover, although polyether, polyvinyl alcohol, a hydroxyl-containing acrylic resin, an epoxy resin, a phenol resin, a polyimide resin, an unsaturated polyester resin etc. are mentioned as a typical organic resin, it is not limited to what was illustrated here.

Next, the pressure-sensitive adhesive containing the isocyanate group-containing organopolysiloxane compound of the present invention will be described.

(A) 100 parts by mass of alcoholic hydroxyl group-containing acrylic polymer [(meth)acrylic copolymer]

(B) 0.001 to 10 parts by mass of the isocyanate group-containing organopolysiloxane compound

(C) 0.01-10 mass parts of polyfunctional crosslinking agent

It is preferable to contain

Thus, as a composition of the adhesive containing the isocyanate group containing organopolysiloxane compound of this invention, 0.001-10 mass parts of (B) an isocyanate group containing organopolysiloxane compound with respect to 100 mass parts of (A) alcoholic hydroxyl group containing acrylic polymers. It is preferable to mix|blend, More preferably, it is 0.01-1 mass part. When it is less than 0.001 parts by mass, the desired adhesive modifying effect is not expressed, and when it exceeds 10 parts by mass, the effect is saturated, the countermeasure effect is lowered, and the effect of the adhesion improvement effect is increased, There is a fear that the adhesiveness of the product becomes excessively high, which is not preferable.

Here, as an alcoholic hydroxyl-containing acrylic polymer, the copolymer of an alcoholic hydroxyl-containing (meth)acrylic monomer and a (meth)acrylic-acid alkylester monomer is mentioned, It can manufacture using a well-known copolymerization procedure. The alcoholic hydroxyl group-containing (meth)acryl monomer may be one that can be obtained as a general industrial product, and examples thereof include hydroxyethyl (meth)acrylate and hydroxybutyl (meth)acrylate. The (meth)acrylic acid alkylester should just be a thing which can be obtained as a general industrial product similarly, and the thing in which an alkyl group is a methyl group, an ethyl group, a propyl group, and a butyl group is mentioned as an example. The content ratio of the alcoholic hydroxyl group-containing (meth)acryl monomer unit with respect to all the monomer units in the said copolymer should just be the range of 0.1-50 mol%, Preferably it is 1-20 mol%. When it is less than 0.1 mol%, desired adhesiveness may not be obtained, and when it exceeds 50 mol%, molding to an adhesive sheet etc. may become difficult by a raise or aggregation of the viscosity of an adhesive.

(C)component in the adhesive which concerns on this invention is a polyfunctional crosslinking agent. (C) The polyfunctional crosslinking agent of component plays a role which raises the cohesive force of an adhesive by reacting with a carboxyl group, a hydroxyl group, etc. 0.01-10 mass parts of content of a crosslinking agent is used with respect to 100 mass parts of (A) component, Preferably it is 0.05-5 mass parts. If it is less than 0.01 mass part, the desired cohesive force improvement effect will not be acquired, but when it exceeds 10 mass parts, aggregation may be caused and shaping|molding to an adhesive sheet etc. may become difficult.

As the polyfunctional crosslinking agent, an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, an aziridine-based crosslinking agent, or a metal chelate-based crosslinking agent may be used, and among them, the isocyanate-based crosslinking agent is easy to use. Examples of the isocyanate-based crosslinking agent include tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoform diisocyanate, tetramethylxylene diisocyanate, naphthalene diisocyanate, and a reaction product of these and a polyol such as trimethylolpropane (trimethyl). allpropane tolylene diisocyanate adduct etc.) etc. are mentioned.

Examples of the epoxy crosslinking agent include ethylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, N,N,N',N'-tetraglycidylethylenediamine, glycerin diglycidyl ether, glycerin triglycidyl ether , polyglycerol polyglycidyl ether, and sorbitol-based polyglycidyl ether.

Examples of the aziridine-based crosslinking agent include N,N'-toluene-2,4-bis(1-aziridinecarboxide), N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxide), A triethylenemelamine, bisisoprothaloyl-1-(2-methylaziridine), tri-1-aziridinylphosphine oxide, etc. are mentioned.

Examples of the metal chelate crosslinking agent include compounds in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium, and vanadium is coordinated with acetylacetone or ethyl acetoacetate.

The manufacturing method of an adhesive is not specifically limited, It is obtained by mixing said (A)-(C) component by a conventional method. It is preferable that mixing conditions shall be 10 minutes - 10 hours at 10-150 degreeC. In this case, the isocyanate group-containing organopolysiloxane compound can be used after polymerization of the (meth)acrylic copolymer by adding it in the blending step, and exhibiting the same effect even when added during the production process of the (meth)acrylic copolymer. In addition, the polyfunctional crosslinking agent can be coated uniformly when the crosslinking reaction of the functional groups of the crosslinking agent hardly occurs in the mixing process performed to form the pressure sensitive adhesive layer obtained by curing the pressure sensitive adhesive. After coating, drying and aging processes are performed to form a cross-linked structure, thereby obtaining a pressure-sensitive adhesive layer having elasticity and strong cohesive force.

The pressure-sensitive adhesive obtained in this way is applied to an adherend such as a glass plate, plastic film, paper, etc., at 25 to 150°C and 20 to 90%RH for 5 minutes to 5 hours, particularly at 40 to 80°C and 25 to 60%RH. A pressure-sensitive adhesive layer can be formed by curing for 10 minutes to 3 hours.

A pressure-sensitive adhesive polarizing plate comprising a pressure-sensitive adhesive layer obtained by coating and curing the pressure-sensitive adhesive on one side or both surfaces of a polarizing film, etc. is to have It does not specifically limit about the polarizing film or polarizing element which comprises a polarizing plate. Examples of the polarizing film include a film obtained by adding a polarizing component such as iodine or a dichroic dye to a film containing a polyvinyl alcohol-based resin and stretching, and the thickness of these polarizing films is not limited, either, and a normal thickness can be molded into

As the polyvinyl alcohol-based resin, polyvinyl alcohol, polyvinyl formal, polyvinyl acetal, and a saponified product of an ethylene/vinyl acetate copolymer, etc. are used.

In addition, on both surfaces of the polarizing film having an adhesive layer, cellulose films such as triacetyl cellulose, polycarbonate films, polyester films such as polyethylene terephthalate films, polyethersulfone films, polyethylene, polypropylene, these A multilayer film or the like in which a protective film such as a polyolefin-based film such as a copolymer is laminated can be formed. At this time, the thickness of these protective films is also not specifically limited, It can shape|mold to a normal thickness.

There is no particular limitation on the method of forming the pressure-sensitive adhesive layer on the polarizing film, and the method of applying the pressure-sensitive adhesive directly to the surface of the polarizing film using a bar coater or the like and drying the pressure-sensitive adhesive is applied to the surface of the releasable substrate and dried. Then, the method of transferring the adhesive layer formed on the surface of this peelable base material to the polarizing film surface, and making it age continuously, etc. are employable. In this case, drying is preferably 5 minutes to 5 hours at 25 to 150°C and 20 to 90%RH, and aging is preferably 5 minutes to 5 hours at 25 to 150°C and 20 to 90%RH.

Although the thickness in particular of an adhesive layer is not restrict|limited, Usually, it is preferable that it is 0.01-100 micrometers, More preferably, it is 0.1-50 micrometers. When the thickness of an adhesive layer is smaller than the said range, the effect as an adhesive layer may become inadequate, when larger than the said range, the effect of an adhesive layer may be saturated and cost may become large.

In the polarizing film (adhesive polarizing plate) having an adhesive layer obtained in this way, one or more layers providing additional functions such as a protective layer, a reflective layer, a retardation plate, a wide viewing angle compensation film, and a brightness improving film can be laminated.

The pressure-sensitive adhesive polarizing plate is particularly applicable to general liquid crystal display devices, and the type of the liquid crystal panel is not particularly limited. In particular, it is preferable to constitute a liquid crystal display device including a liquid crystal panel in which the pressure-sensitive adhesive polarizing plate of the present invention is bonded to one side or both sides of a liquid crystal cell in which liquid crystal is sealed between a pair of glass substrates.

The pressure-sensitive adhesive of the present invention, in addition to the above-described polarizing film, can be used without limitation to industrial sheets, particularly reflective sheets, structural adhesive sheets, photographic adhesive sheets, lane marking adhesive sheets, optical adhesive products, electronic components, etc. can In addition, it can be applied to multi-layered laminate products, that is, general commercial adhesive sheet products, medical patches, and heat-activated applications, with the same concept of action.

The pressure-sensitive adhesive of the present invention is a (meth)acrylic pressure-sensitive adhesive comprising an organopolysiloxane compound having an isocyanate group containing a sulfur atom in a linked chain and preferably a hydrocarbyloxy group, and has a low initial adhesive strength when attached to glass, ITO, etc. Therefore, it is excellent in rework property, and the adhesive force after the wet heat treatment after sticking becomes a thing high enough, and it is excellent in long-term durability.

[Example]

Hereinafter, the present invention will be described in more detail by describing Examples and Comparative Examples, but the present invention is not limited to these Examples. In addition, in the following examples, viscosity, specific gravity, and refractive index are values measured at 25°C. In addition, IR is an abbreviation for infrared absorption spectroscopy, and NICOLET6700 manufactured by Thermo sientific was used as the apparatus. NMR is an abbreviation for nuclear magnetic resonance spectroscopy, and the apparatus used was AVANCE400M manufactured by Bruker. Viscosity is based on measurement at 25° C. with a capillary kinematic viscometer.

[Example 1]

[Synthesis of an organopolysiloxane compound having a structure of a = 0.25, b = 0, c = 0.75, d = 1.33, and e = 0 in the average composition formula (1)]

In a 1L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer, 483 g of mercaptopropyl group, methyl group and methoxy group-containing organopolysiloxane compound having a mercapto amount of 483 g/mol (mercapto group amount: 1 mol, a=0.25, b =0, c=0.75, d=1.33, and e=0), 2 g of 2,2'-azobis(2-methylbutyronitrile) was added, and the mixture was heated to 90°C. 141.1 g (1 mol) of 2-isocyanatoethyl acrylate was dripped therein. The dropping rate was adjusted so that heat_generation|fever generate|occur|produced by reaction and internal temperature might not exceed 95 degreeC. After completion|finish of dripping, it heat-stirred at 90 degreeC for 1 hour, it confirmed that the peak of the acryl site|part derived from 2-isocyanatoethyl acrylate of a raw material disappeared by proton NMR measurement, and it was set as reaction completion|finish. The obtained reaction product had a pale yellow liquid, a viscosity of 21.9 mm 2 /s, a specific gravity of 1.17, and a refractive index of 1.444. The IR spectrum and ¹ H-NMR spectrum of the reactant are shown in FIGS. 1 and 2 .

[Examples 2 to 6]

Except for changing the mercaptopropyl group-containing organopolysiloxane compound used in Example 1 to another mercaptopropyl group-containing organopolysiloxane compound shown in Table 1 below, under the same conditions such as the reaction functional group ratio, the corresponding isocyanate groups A containing organopolysiloxane compound was obtained.

[Example 7]

[Synthesis of an organopolysiloxane compound having a structure of a = 0.125, b = 0.125, c = 0.75, d = 1.33, and e = 0 in the average composition formula (1)]

In a 1L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer, 483 g of mercaptopropyl group, methyl group and methoxy group-containing organopolysiloxane compound having a mercapto amount of 483 g/mol (mercapto group amount: 1 mol, a=0.25, b =0, c=0.75, d=1.33, and e=0), 2 g of 2,2'-azobis(2-methylbutyronitrile) was added, and the mixture was heated to 90°C. 275 g (vinyl group weight: 0.5 mol) of polyethyleneglycol methyl allyl ether which is 550 g/mol of vinyl amount was dripped there. The dropping rate was adjusted so that heat_generation|fever generate|occur|produced by reaction and internal temperature might not exceed 95 degreeC. 70.5 g (0.5 mol) of 2-isocyanatoethyl acrylate was dripped after completion|finish of dripping successively. The dropping rate was adjusted so that heat_generation|fever generate|occur|produced by reaction and internal temperature might not exceed 95 degreeC. After completion|finish of dripping, it heat-stirred at 90 degreeC for 1 hour, it confirmed that the olefin peak derived from dripping raw material had lose|disappeared by proton NMR measurement, and it was set as reaction completion|finish. The obtained reaction product had a pale yellow liquid, a viscosity of 51.3 mm 2 /s, a specific gravity of 1.14, and a refractive index of 1.450. The IR spectrum and ¹ H-NMR spectrum of the reactant are shown in FIGS. 3 and 4 .

[Examples 8 and 9]

An isocyanate group and polyether group-containing organopolysiloxane compound shown in Table 2 below under the same conditions except that the functional group ratio of 2-isocyanatoethyl acrylate and polyethylene glycol methyl allyl ether used in Example 7 was changed. got it

[Example 10]

An isocyanate group and β-ketoester group-containing organopolysiloxane compound shown in Table 3 was obtained under the same conditions except that the polyethylene glycol methyl allyl ether used in Example 7 was changed to allyl acetyl acetate.

Preparation of polyurethane elastomer for adhesion test

150 parts by mass of polyoxytetramethylene glycol having a number average molecular weight of 1,000, 100 parts by mass of 1,6-hexylene glycol, 0.5 parts by mass of water, 200 parts by mass of hexamethylene diisocyanate, and 800 parts by mass of dimethylformamide by mixing with stirring at 90°C After heating and stirring as it is for 2 hours to react, 3 parts by mass of dibutylamine was added to stop the reaction, and then, an excess of amine was neutralized with acetic anhydride to obtain a polyurethane elastomer.

of primer adhesion test

To a glass plate, a toluene solution containing 10 wt% of the organopolysiloxane compound of this example or the organosilicon compound of the comparative example is applied with a brush as a primer, dried at 80 ° C. for 5 minutes, and then a polyurethane elastomer is applied again with a brush, and at 100 ° C. dried for 10 minutes. Subsequently, perforations were placed in the obtained coating film at intervals of 1 mm in length and width to form 100 grids, and then pressed with cellophane tape and then peeled off. evaluated. Regarding the primers obtained in Examples, there was no peeling checkerboard on any of the substrates, and the adhesive performance was very good. A result is shown in Table 4.

Comparative Example 1: Isocyanatepropyltriethoxysilane

Comparative Example 2: Isocyanatepropyltrimethoxysilane

The primer adhesion test demonstrated that the isocyanate group-containing organopolysiloxane compound of the present invention is useful as a primer compared with the conventional isocyanate group-containing silane coupling agent. As a factor in which such adhesiveness was expressed, since this invention is polysiloxane containing a hydrocarbyloxy group, it has reactivity with an inorganic material, and the thing with favorable film-forming property by a polymer is mentioned.

[Examples 11 to 15, Comparative Examples 3 to 7]

Preparation of acrylic polymer for adhesive test

In a 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer, 98.1 g of n-butyl acrylate (BA), 0.6 g of 4-hydroxybutyl acrylate (4-HBA), and 2-hydroxyethyl meta 1.3 g of acrylate (2-HEMA) was added, and 100 g of ethyl acetate was added as a solvent, and it was dissolved. Then, in order to remove oxygen, nitrogen gas bubbling was performed for 1 hour, the inside of the reaction system was replaced with nitrogen, and it maintained at 62 degreeC. In this, 0.03 g of azobisisobutyronitrile was added as a polymerization initiator while stirring, and the (meth)acrylic copolymer which is an acrylic polymer (base polymer) was obtained by making it react at 62 degreeC for 8 hours.

Preparation of adhesive

(A) Acrylic polymer obtained above: With respect to 100 parts by mass of (meth)acrylic copolymer, (B) Adhesive modifier: Organopolysiloxane compound obtained in Examples 1 and 7 to 10 or organosilicon of Comparative Examples 1 and 2 As a compound and (C) a crosslinking agent, trimethylol propane tolylene diisocyanate adduct (TDI) was mixed with the compounding composition shown in Tables 5 and 6, respectively, and it was set as the adhesive Example and the comparative example.

After coating the obtained pressure-sensitive adhesive on a release paper and drying it, a uniform pressure-sensitive adhesive layer of 25 μm was obtained. The thus-prepared pressure-sensitive adhesive layer was subjected to adhesion processing on an iodine-based polarizing plate having a thickness of 185 μm, and then the obtained polarizing plate was cut to an appropriate size and used for each evaluation.

About the test cylinder of the manufactured polarizing plate, durability reliability, glass adhesive force, rework property, and the change of adhesive force in heat resistance or moist heat resistance conditions were evaluated through the evaluation test method shown below, and the result is shown in Table 7.

evaluation exam

<Durability Reliability>

A polarizing plate (90 mm x 170 mm) coated with an adhesive was affixed to a glass substrate (110 mm x 190 mm x 0.7 mm) in a state in which optical absorption axes were crossed on both sides. At this time, the applied pressure was about 5 kgf/cm 3 , and the operation was performed in a clean room so that bubbles or foreign substances were not generated.

In order to evaluate the heat-and-moisture resistance characteristic of this test piece, after leaving it to stand under the conditions of 60 degreeC/90%RH for 1000 hours, the presence or absence of generation|occurrence|production of a bubble or peeling was confirmed. As for the heat resistance characteristic, after leaving it to stand at 80 degreeC/30%RH for 1000 hours, the mode of bubble and peeling was observed. In addition, before evaluating the state of a test piece, it is left still at room temperature (23 degreeC/60%RH) for 24 hours.

The evaluation criteria regarding durability evaluation are as follows.

○: No bubble or peeling phenomenon

(triangle|delta): There is a slight bubble or peeling phenomenon

x: There are many bubbles and peeling phenomena

<Glass Adhesion>

After aging the pressure-sensitive adhesive-coated polarizing plate at room temperature (23°C/60%RH) for 7 days, the polarizing plate was cut into 1-inch × 6-inch sizes, respectively, and 0.7 mm thick radish using a 2 kg rubber roller. It was affixed to alkali glass. After storage at room temperature for 1 hour, the initial adhesive strength was measured, followed by aging at 50°C for 4 hours, and then after storage at room temperature for 1 hour, the adhesive strength was measured.

<Rework Castle>

A polarizing plate (90 mm × 170 mm) coated with an adhesive is attached to a glass substrate (110 mm × 190 mm × 0.7 mm), then left at room temperature (23°C/60%RH) for 1 hour, and then at 50°C × 4 hours After aging and leaving to cool at room temperature for 1 hour, the polarizing plate was peeled from the glass.

Without destroying a polarizing plate or a glass plate, without leaving an adhesive material on the glass surface, it evaluated as follows on the basis of whether peeling was possible.

○: Easily re-peelable

△: slightly difficult to re-peel (adhesive remains on the glass surface)

×: not peelable, glass or polarizing plate is broken

Comparative Example 3 did not contain an adhesion modifier, and sufficient adhesion did not develop after heat curing. Comparative Examples 4 and 5 are cases of using an isocyanate propyl group-containing silane coupling agent, which is an existing technology, and although reworkability of initial adhesive force is expressed, the affinity with the resin is relatively insufficient, so the final adhesion strength after curing is insufficient. Do. Since there are too few (B) components to be used in the comparative example 6, the effect is inadequate. On the other hand, since comparative example 7 had too much usage-amount of (B) component, excessive adhesiveness was expressed from the initial stage, and rework property has become inadequate.

As mentioned above, the adhesive of this invention is excellent in initial stage rework property, expresses sufficient adhesive force with glass by high temperature and high temperature and humidity processing, and proves that it is an adhesive excellent in long-term durability.

Claims (14)

The following average composition formula (1)
Y _a R ¹ _b R ² _c Si(OR ³ ) _d (OH) _e O _(4-abcde)/2 … (One)
(Wherein, Y is an organic group containing a thioether linking group and an isocyanate group, R ¹ is a monovalent hydrocarbon group having 1 to 18 carbon atoms or a thioether linking group containing a thioether linking group and a polyether group as functional groups, and β- a monovalent hydrocarbon group having 1 to 18 carbon atoms including a ketoester group as a functional group, R ² is a monovalent hydrocarbon group having 1 to 18 carbon atoms not including a functional group, and R ³ is a monovalent hydrocarbon group having 1 to 4 carbon atoms is a monovalent hydrocarbon group of, a, b, c, d and e are each represented by 0.01≤a≤1, 0.1≤b<1, 0≤c≤2, 0≤d≤2 and 0≤e≤1, respectively. An organopolysiloxane compound containing an isocyanate group-containing organic group, which is a number and also satisfies 2≤a+b+c+d+e≤3). The organopolysiloxane compound according to claim 1, wherein b is 0.125≤b<1. A method for producing an organopolysiloxane compound containing an isocyanate group-containing organic group according to claim 1 or 2,
(i) an organopolysiloxane compound containing a mercapto group-containing organic group represented by the following general formula (2);
B _a R ¹ _b R ² _c Si(OR ³ ) _d (OH) _e O _(4-abcde)/2 … (2)
(Wherein, B is an organic group containing a mercapto group, R ¹ , R ² , R ³ , a, b, c, d and e have the same meaning as above, and 2≤a+b+c+d+ satisfies e≤3)
(ii) an unsaturated double bond-containing isocyanate compound represented by the following general formula (3)

(wherein Z is a monovalent hydrocarbon group having 2 to 10 carbon atoms which may include an unsaturated double bond and may have an ester bond interposed therebetween)
A method for producing an organopolysiloxane compound containing an isocyanate group-containing organic group, characterized in that the ene-thiol addition reaction is carried out in the presence of a radical generator. An adhesive comprising the organopolysiloxane compound containing the isocyanate group-containing organic group according to claim 1 or 2. It is an adhesive comprising the organopolysiloxane compound containing the isocyanate group-containing organic group according to claim 1 or 2,
(A) 100 parts by mass of alcoholic hydroxyl group-containing acrylic polymer
(B) 0.001 to 10 parts by mass of the organopolysiloxane compound containing the isocyanate group-containing organic group
(C) 0.01-10 mass parts of polyfunctional crosslinking agent
Adhesive, characterized in that it contains. A coating agent comprising the organopolysiloxane compound containing the isocyanate group-containing organic group according to claim 1 or 2. An article coated or surface-treated with the coating agent according to claim 6 . The article according to claim 7, wherein the substrate to be covered or surface treated by the coating agent is a glass fiber product selected from glass cloth, glass tape, glass mat, glass paper. The article according to claim 7, wherein the substrate coated or surface treated with the coating agent is an inorganic filler. The article according to claim 7, wherein the substrate to be covered or surface treated by the coating agent is a ceramic or a metal. It has a polarizing film and the adhesive layer formed from the adhesive of Claim 5 on one side or both surfaces of this polarizing film, The adhesive polarizing plate characterized by the above-mentioned. A liquid crystal display device comprising: a liquid crystal cell in which a liquid crystal is sealed between a pair of glass substrates; and a liquid crystal panel having the pressure-sensitive adhesive polarizing plate according to claim 11 adhered to one or both surfaces of the liquid crystal cell. delete delete

Images