JP6272109B2 - Adhesive composition, adhesive sheet, and method for producing adhesive sheet - Google Patents

Description

  The present invention relates to a pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet, and a method for producing a pressure-sensitive adhesive sheet. In particular, the present invention relates to a pressure-sensitive adhesive composition having low peeling characteristics and good constant load properties, a pressure-sensitive adhesive sheet using such a pressure-sensitive adhesive composition, and a method for producing a pressure-sensitive adhesive sheet.

Conventionally, the pressure-sensitive adhesive sheet has an advantage that it can be easily attached to an adherend by pressing, and thus has been used in many fields as a display label or an electronic component adhesive material.
Here, what uses the terminal silyl group polymer as an adhesive layer used for such an adhesive sheet is proposed. The terminal silyl group polymer is a polymer in which a hydrolyzable silyl group is bonded to the terminal and becomes a three-dimensional network structure by curing.

Therefore, for example, a pressure-sensitive adhesive sheet using a pressure-sensitive adhesive composition containing a predetermined terminal silyl group polymer as a main agent has been proposed (for example, Patent Document 1).
More specifically, 100 parts by mass of a terminal silyl group polymer having a urethane bond and / or a urea bond in the main chain or side chain and containing a hydrolyzable silyl group at the terminal, and 10 to 150 parts by mass of a tackifier resin , A pressure-sensitive adhesive precursor in which 0.001 to 10 parts by mass of a fluorine compound selected from the group consisting of boron trifluoride and / or a complex thereof, a fluorinating agent and an alkali metal salt of a fluorine-based inorganic acid are uniformly mixed Is applied to the surface of a tape base material or a sheet base material, and then the terminal silyl group polymer is cured, whereby the pressure sensitive adhesive precursor is used as a pressure sensitive adhesive layer. .

In addition, a urethane resin-based curable resin composition excellent in adhesion to a wide range of materials such as metal, plastic, wood, and inorganic materials has been proposed (for example, Patent Document 2).
More specifically, (a) a main chain is a polyoxyalkylene polymer containing at least polyoxyethylene, and a urethane-based resin (A) having a predetermined structure and (b) a polymerizable vinyl group-containing monomer are polymerized. A urethane resin-based curable resin composition containing a vinyl polymer (B) as a component is disclosed.

WO2010 / 038715 (Claims etc.) JP 2002-212415 A (Claims etc.)

However, the pressure-sensitive adhesive sheet described in Patent Document 1 must contain a considerable amount of a fluorine compound such as boron trifluoride or a fluorinating agent as a curing catalyst for increasing the reactivity of the terminal silyl group in the terminal silyl group polymer. However, there are problems that the manufacturing cost is high, reaction control is difficult, and handling properties are difficult depending on the type of the curing catalyst.
Furthermore, although there is a description that a functional oligomer such as an acrylic oligomer may be added as one of the additives, the type and amount thereof are not mentioned, and the obtained adhesive tape is peeled off. There was a problem of relatively high power.
In addition, the urethane resin-based curable resin composition described in Patent Document 2 contains a vinyl polymer as a component in the resin composition, and thus has excellent adhesion to metals, plastics, etc. In addition to the complicated process, the viscosity of the resin composition was high, and there was a problem that handling was not easy.

Therefore, the present inventors made extensive efforts in view of the circumstances as described above. As a result, by blending a predetermined (meth) acrylic acid ester polymer and a tackifying resin into the terminal silyl group polymer, low peeling is achieved. The present invention has been completed by finding out the characteristics and obtaining a good constant load property.
That is, an object of the present invention is to provide a pressure-sensitive adhesive composition that exhibits low peeling characteristics and obtains good constant loadability, a pressure-sensitive adhesive sheet using such a pressure-sensitive adhesive composition, and efficient production of the pressure-sensitive adhesive sheet. It is to provide a method.

According to the present invention, a pressure-sensitive adhesive comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifying resin as the component (C). The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, and a urethane bond and a urea bond in a part of the main chain or a side chain, or any one of them Furthermore, it has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain, and the (meth) acrylic acid ester polymer as the component (B) is a carboxyl group. group-containing (meth) one acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or either only contains and tackifying resin as the component (C), fully hydrogenated Terupenfu Nord-based is a resin, in the pressure-sensitive adhesive sheet having an adhesive layer comprising the adhesive composition, the silicon element concentration of the surface of the pressure-sensitive adhesive layer of the adhesive sheet according to elemental analysis of XPS and Z _1, the pressure-sensitive adhesive The silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the (meth) acrylic acid ester polymer as the component (B) from the composition Provided is a pressure-sensitive adhesive composition characterized in that the silicon concentration change rate Z represented by the following general formula (A) is a value of 83% or less when Z ₀ is satisfied , and solves the above-mentioned problems can do.

(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)

That is, in the pressure-sensitive adhesive composition of the present invention, (B) component (meth) acrylic ester polymer and (C) component tackifier resin with respect to terminal silyl group polymer (A) component. And the (meth) acrylic acid ester polymer as component (B) has a predetermined functional group, so that the pressure-sensitive adhesive composition has low release characteristics and good constant loadability. Can be demonstrated.
Moreover, since the terminal silyl group polymer as the component (A) has hydrolyzable silyl groups represented by the general formula (1) at both ends of the main chain, the crosslink density between the components (A) is suitable. By adjusting the range, the balance between the adhesive force and the cohesive force in the pressure-sensitive adhesive composition can be improved.
Furthermore, since the terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, it can impart appropriate flexibility to the resulting pressure-sensitive adhesive composition.
In addition, when the (meth) acrylic acid ester polymer which is (B) component is a carboxyl group-containing (meth) acrylic acid ester copolymer, it means a copolymer composed of a plurality of types of monomers.
On the other hand, when the (meth) acrylic acid ester polymer as the component (B) is a non-functional (meth) acrylic acid ester polymer, a plurality of types of monomers may be used even if the polymer is a single monomer. The copolymer which consists of may be sufficient.
Furthermore, the (meth) acrylic acid ester polymer as the component (B) may contain both a carboxyl group-containing (meth) acrylic acid ester copolymer and a non-functional (meth) acrylic acid ester polymer.

Moreover, when comprising the adhesive composition of this invention, it is preferable that the weight average molecular weight of the (meth) acrylic acid ester polymer as (B) component is a value within the range of 800-3,000,000. .
By comprising in this way, an adhesive composition has a low peeling characteristic and can exhibit favorable constant load property.

Moreover, in comprising the adhesive composition of this invention, the compounding quantity of the (meth) acrylic acid ester polymer as (B) component is 0 with respect to 100 weight part of terminal silyl group polymers as (A) component. It is preferably a value within the range of 1 to 150 parts by weight.
By comprising in this way, an adhesive composition has a low peeling characteristic and can exhibit favorable constant load property.

Further, in constituting the pressure-sensitive adhesive composition of the present invention, the blending amount of the tackifying resin as the component (C) is 50 to 140 parts by weight with respect to 100 parts by weight of the terminal silyl group polymer as the component (A). A value within the range is preferred.
By comprising in this way, the balance between the adhesive force and cohesion force in an adhesive composition can be made more favorable.

Moreover, when comprising the adhesive composition of this invention, it is preferable that the weight average molecular weight of the terminal silyl group polymer which is (A) component is a value within the range of 15,000-200,000.
By comprising in this way, the balance among the softness | flexibility, adhesive force, and cohesion force in an adhesive composition can be made more favorable.

Moreover, when comprising the adhesive composition of this invention, it is preferable that the gel fraction of an adhesive composition is a value within the range of 20-70%.
By comprising in this way, the outstanding cohesion force can be exhibited.
More specifically, even if the pressure-sensitive adhesive layer has a relatively high cohesive force, good constant load properties can be obtained.

Another aspect of the present invention is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer comprising the above-mentioned pressure-sensitive adhesive composition.
That is, since the above-mentioned pressure-sensitive adhesive sheet has low release characteristics and good constant load properties, even if this pressure-sensitive adhesive sheet includes a release sheet, it can be easily peeled off and It can be satisfactorily bonded to the body.

  Moreover, when comprising the adhesive sheet of this invention, it is preferable that it is an adhesive sheet which has the above-mentioned adhesive layer in the at least single side | surface of a base material.

  Moreover, when comprising the adhesive sheet of this invention, it is preferable that it is an adhesive sheet which has a structure where the adhesive layer was pinched | interposed with two peeling sheets.

Another embodiment of the present invention is a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a pressure-sensitive adhesive composition on both sides or one side of a base material, and a release sheet on the surface opposite to the base material of the pressure-sensitive adhesive layer. It is a manufacturing method of this, Comprising: It is a manufacturing method of the adhesive sheet characterized by including following process (1)-(3). (1) A pressure-sensitive adhesive composition comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifying resin as the component (C). The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, and has a urethane bond and / or a urea bond in a part of the main chain or a side chain. Furthermore, it has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain, and the (meth) acrylate polymer as the component (B) contains a carboxyl group ( meth) one acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or either only contains, and, (C) a tackifier resin as component, fully hydrogenated terpene phenol Preparing a fat and a pressure-sensitive adhesive composition

(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)

(2) A step of laminating the pressure-sensitive adhesive composition on both sides or one side of the substrate and forming a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a non-cured pressure-sensitive adhesive composition (3) heating the pressure-sensitive adhesive composition From the pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a cured pressure-sensitive adhesive composition, the silicon element concentration of the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet measured by XPS elemental analysis as Z ₁ , The silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the (meth) acrylic acid ester polymer as the component (B) is Z ₀ . When the silicon concentration change rate Z represented by the following general formula (A) is 83% or less,

By carrying out like this, the adhesive sheet which has a low peeling characteristic and favorable constant load property can be manufactured efficiently.
More specifically, a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer containing a predetermined functional group as the component (B), and a tackifier resin as the component (C) By containing at least, it is possible to stably obtain a pressure-sensitive adhesive sheet that can be easily peeled from the release sheet and that exhibits good pressure-sensitive adhesive properties with respect to the adherend.

Still another embodiment of the present invention is a method for producing a pressure-sensitive adhesive sheet that does not include a substrate, includes a pressure-sensitive adhesive layer made of a pressure-sensitive adhesive composition, and has release sheets on both sides of the pressure-sensitive adhesive layer, It is the manufacturing method of the adhesive sheet characterized by including following process (1)-(3).
(1) A pressure-sensitive adhesive composition comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifying resin as the component (C). The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, and has a urethane bond and / or a urea bond in a part of the main chain or a side chain. further, the both ends of the main chain, has a hydrolyzable silyl group represented by the following general formula (1), wherein (B) as component (meth) acrylic acid ester polymer, a carboxyl group-containing (meth) viewed contains one acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or any, and, (C) a tackifier resin as component, fully hydrogenated terpene phenol Preparing a pressure-sensitive adhesive composition is a system resin

(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)

(2) Step of forming a pressure-sensitive adhesive sheet with a pressure-sensitive adhesive layer comprising a non-cured pressure-sensitive adhesive composition by laminating the pressure-sensitive adhesive composition on the surface of the release sheet (3) heating and curing the pressure-sensitive adhesive composition From the pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet comprising a pressure- sensitive adhesive composition is used, and the silicon element concentration on the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet measured by XPS elemental analysis is Z _1. ) when the (meth) silicon element concentration of the surface of the pressure-sensitive adhesive layer according to the XPS elemental analysis of the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive composition was prepared except the acrylic acid ester polymer as a component and a Z ₀ And the silicon concentration change rate Z represented by the following general formula (A) is 83% or less.

By carrying out in this way, a pressure-sensitive adhesive sheet having low peeling characteristics and good constant load can be efficiently produced even without a substrate.
More specifically, a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer containing a predetermined functional group as the component (B), and a tackifier resin as the component (C) By containing at least, it is possible to stably obtain a pressure-sensitive adhesive sheet that can be easily peeled from the release sheet and that exhibits good pressure-sensitive adhesive properties with respect to the adherend.

FIGS. 1A to 1B are reaction formulas for explaining a synthesis method and a curing reaction of a predetermined terminal silyl group polymer, respectively. 2 (a) to 2 (b) are FT-IR spectra of tackifying resins (non-hydrogenated terpene phenol resin and fully hydrogenated terpene phenol resin), respectively. Drawing 3 (a)-(d) is a figure offered in order to explain the mode of an adhesive sheet, respectively. FIGS. 4A to 4C are diagrams provided to explain the surface state of the pressure-sensitive adhesive layer when a carboxyl group-containing (meth) acrylic acid ester copolymer is used. FIG. 5 is a diagram provided for explaining the relationship between the change rate of the silicon atom concentration and the adhesive property. FIGS. 6A to 6C are diagrams provided for explaining the surface state of the pressure-sensitive adhesive layer in the case of using a nonfunctional (meth) acrylic acid ester polymer.

[First Embodiment]
The first embodiment of the present invention includes at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), a tackifying resin as the component (C), The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, and a urethane bond and a urea bond in a part or a side chain of the main chain, Or it has any one, Furthermore, it has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain, and (B) component (meth) acrylic acid ester heavy coalescing comprises one carboxyl group-containing (meth) acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or any, and the tackifying resin as the component (C), fully hydrogenated A Le Pen phenolic resin, in the pressure-sensitive adhesive sheet having an adhesive layer comprising the adhesive composition, the silicon element concentration of the surface of the pressure-sensitive adhesive layer of the adhesive sheet according to elemental analysis of XPS and Z _1, wherein the adhesive Concentration of silicon element on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the (meth) acrylate polymer as the component (B) from the pressure-sensitive adhesive composition When Z is Z ₀ , the pressure-sensitive adhesive composition is characterized in that the silicon concentration change rate Z represented by the following general formula (A) is a value of 83% or less .

(In general formula (1), X1 and X2 are independent and are a hydroxyl group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)
Hereinafter, the pressure-sensitive adhesive composition of the first embodiment of the present invention will be specifically described with reference to the drawings as appropriate.

1. (A) Component: Terminal silyl group polymer (1) Basic constitution The terminal silyl group polymer as the component (A) has a urethane bond and / or a urea bond in the main chain or side chain, or one of the main chain It has the hydrolyzable silyl group represented by the general formula (1) described above at both ends.
The reason for this is that the component (A) has a bifunctional hydrolyzable terminal silyl group represented by the general formula (1), and is therefore effective by hydrolytic dehydration condensation between the components (A). This is because a three-dimensional network structure can be formed.
Therefore, excellent adhesive strength can be exhibited by combination with a predetermined tackifying resin, and good adhesive properties can be exhibited when used in an adhesive sheet.
Moreover, if it is such (A) component, since it has the bifunctional hydrolyzable terminal silyl group represented by General formula (1), the gel fraction in the adhesive composition after hardening is a predetermined range. By adjusting to, an excellent cohesive force can be exhibited.
Therefore, even when the pressure-sensitive adhesive composition is applied to the pressure-sensitive adhesive sheet and processed into a roll shape, the pressure-sensitive adhesive can be prevented from leaching from the side surface over time.
Therefore, the adhesive composition excellent in the balance between adhesive force and cohesive force can be obtained by using a predetermined terminal silyl group polymer as the component (A).
In general formula (1), the alkyl group represented by R has 1 to 20 carbon atoms, more preferably 1 to 12 because of good hydrolytic dehydration condensation reactivity. More preferably, it is ~ 3.
Further, in the general formula (1), when X ¹ or X ² is an alkoxy group, the number of carbon atoms in the alkoxy group is preferably 1 to 12 because of good hydrolytic dehydration condensation reactivity, It is more preferable that it is 1-3.

And this terminal silyl group polymer is comprised from the predetermined | prescribed terminal part and the predetermined | prescribed frame | skeleton part.
In addition, the urethane prepolymer (diisocyanate compound) represented by the formula (1) and the halogenated silyl group represented by the formula (2) shown in FIG. 1A are represented by the formula (3). A specific method for synthesizing the terminal silyl group polymer will be described in the third embodiment.

  First, specific structures of terminal portions in the terminal silyl group polymer represented by the formula (3) in FIG. 1A are shown in the following general formulas (2) to (8) (terminal portions -AG). .

(In the general formula (2), R ² and R ³ are alkyl groups having 1 to 20 carbon atoms, more preferably 1 to 8 carbon atoms, and R, X ¹ and X ² are the same as in the case of the general formula (1). The same applies to the following general formulas (3) to (8).)

(In the general formula (8), X ³ represents an alkylene group, and X ⁴ represents an organic group having 1 to 20 carbon atoms such as an alkyl group or an aryl group.)

  That is, when the terminal silyl group polymer has such a terminal portion, it causes a curing reaction by dehydration condensation as shown in FIG. 1B, and further strengthens the adhesion to the adherend. be able to.

In addition, the skeleton of the main chain or side chain of the terminal silyl group polymer represented by the formula (3) in FIG. 1A is characterized by a polyoxyalkylene structure.
The reason for this is that by having a polyoxyalkylene structure in the molecule, it is possible to impart appropriate flexibility to the resulting pressure-sensitive adhesive composition, and to further improve the adhesion to the adherend. It is.
Specific examples of such polyoxyalkylene include polyoxypropylene and polyoxyethylene.

Further, the predetermined terminal silyl group polymer as the component (A) does not have the hydrolyzable silyl group represented by the general formula (1) in the side chain as shown in FIG. It is characterized by being a both-terminal silyl group polymer having a hydrolyzable silyl group represented by the general formula (1) only at both terminals.
The reason for this is that, with such a silyl group polymer at both terminals, the crosslink density between the components (A) is adjusted to a suitable range, and the balance between the adhesive force and cohesive force in the cured adhesive composition can be easily adjusted. It is because it can be made.

In addition, as the component (A ′), the polymer further contains a one-terminal silyl group polymer having a hydrolyzable silyl group represented by the general formula (1) only at one end of the main chain, A value within the range of 0.1 to 30 parts by weight with respect to 100 parts by weight of the polymer is preferable.
The reason for this is that the cross-linking density between the components (A) is adjusted to a more suitable range by mixing the one-end silyl group polymer within a predetermined range with respect to the both-end silyl group polymer, and the pressure-sensitive adhesive after curing This is because the balance between the adhesive force and the cohesive force in the composition can be further easily adjusted.
That is, when the blending amount of the one-terminal silyl group polymer is 0.1 parts by weight or more, the effect of addition can be sufficiently exhibited. On the other hand, if the blending amount of the one-terminal silyl group polymer is a value of 30 parts by weight or less, it becomes easy to adjust the crosslinking density of the components (A) to a suitable range, and a predetermined gel fraction can be obtained. This is because it can.
Therefore, it is more preferable that the blending amount of the one-terminal silyl group polymer is a value within the range of 0.5 to 10 parts by weight with respect to 100 parts by weight of the both-end silyl group polymer, and a range of 1 to 5 parts by weight. It is more preferable that the value be within the range.
However, since it has been confirmed that a pressure-sensitive adhesive composition having excellent adhesive force can be obtained even when only the both-end silyl group polymer is used, if not particularly required, a one-end silyl group polymer is used. It is also preferable to use only the terminal silyl group polymer without mixing from the viewpoint of simplification of the production process.

(2) Weight average molecular weight Moreover, it is preferable that the weight average molecular weight of the terminal silyl group polymer which is (A) component is a value within the range of 15,000-200,000.
The reason for this is that when the weight average molecular weight of the terminal silyl group polymer is a value of 15,000 or more, the crosslinking density is adjusted to a suitable range, sufficient adhesive strength can be obtained, and the viscosity is adjusted to a suitable range. This is because it becomes easy to adjust and processability at the time of forming a sheet by solution coating can be improved.
On the other hand, if the weight average molecular weight of the terminal silyl group polymer is a value of 200,000 or less, it becomes easy to adjust the viscosity to a suitable range, and the workability at the time of forming a sheet by solution coating can be improved. This is because the crosslinking density can be adjusted within a suitable range, and it is easy to adjust the balance between adhesive force and cohesive force.
Therefore, the weight average molecular weight of the terminal silyl group polymer as the component (A) is more preferably a value in the range of 20,000 to 150,000, and a value in the range of 30,000 to 100,000. More preferably.
In addition, the weight average molecular weight of the terminal silyl group polymer which is (A) component can be measured using well-known molecular weight measuring apparatuses, such as a gel permeation chromatography (GPC).
In addition, when mix | blending (A ') component mentioned above, it can be made to be the same as that of (A) component also about the weight average molecular weight of (A') component.

(3) Compounding quantity Moreover, the compounding quantity of the terminal silyl group polymer which is (A) component shall be the value within the range of 20 to 90 weight% with respect to 100 weight% of the whole quantity of an adhesive composition. preferable.
The reason for this is that when the blending amount of the terminal silyl group polymer is 20% by weight or more, the absolute amount of the component (A) with respect to the entire pressure-sensitive adhesive composition is in a suitable range, and sufficient cohesive force can be obtained. Because.
On the other hand, if the blending amount of the terminal silyl group polymer is a value of 90% by weight or less, the absolute amount of the component (A) with respect to the entire pressure-sensitive adhesive composition is in a suitable range, and sufficient adhesive strength can be obtained. It is.
Therefore, the blending amount of the terminal silyl group polymer as the component (A) is more preferably within a range of 25 to 85% by weight with respect to 100% by weight of the total amount of the pressure-sensitive adhesive composition. More preferably, the value is within the range of 80% by weight.

2. (B) component: (meth) acrylic acid ester polymer (1) structure Moreover, the (meth) acrylic acid ester polymer as (B) component is a carboxyl group-containing (meth) acrylic acid ester copolymer and non-functional. It contains a (meth) acrylic acid ester polymer or one of them.
The reason for this is that the pressure-sensitive adhesive composition contains a carboxyl group-containing (meth) acrylic acid ester copolymer and a non-functional (meth) acrylic acid ester polymer, or one of them, as will be described later. This is because, when prepared, the pressure-sensitive adhesive sheet can be easily peeled off from the release sheet, and when it is bonded to an adherend, good pressure-sensitive adhesive properties can be imparted.

(1) -1. Carboxyl group-containing (meth) acrylic acid ester copolymer The kind of carboxyl group-containing (meth) acrylic acid ester copolymer is not particularly limited, and a copolymer moiety derived from a carboxyl group-containing vinyl monomer; Any other carboxyl group-containing (meth) acrylate copolymer can be used as long as it has a copolymer moiety derived from other (meth) acrylate monomers or vinyl monomers. .

  More specifically, examples of the carboxyl group-containing vinyl monomer include acrylic acid, methacrylic acid, maleic acid, itaconic acid, maleic acid monomethyl ester, citraconic acid monomethyl ester, 2-carboxyethyl acrylate, 2-carboxyethyl methacrylate, One kind of succinic acid mono (2-acryloyloxyethyl), one kind of succinic acid mono (2-methacryloyloxyethyl), or a combination of two or more kinds may be mentioned.

  On the other hand, as other (meth) acrylic acid ester monomers and vinyl monomers, for example, alkyl such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, etc. (Meth) acrylic acid alkyl ester having 1 to 20 carbon atoms, hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) acrylic Hydroxyl group-containing vinyl monomers such as 2-hydroxybutyl acid, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, vinyl ethers such as hydroxybutyl vinyl ether, monomethylaminoethyl (meth) acrylate, acrylamide, Nitrogen-containing vinyl compounds such as acryloylmorpholine Mer, ethylene, olefins such as propylene, aromatic vinyl monomers such as styrene, in combination alone or two or more vinyl esters such as vinyl acetate and the like.

Moreover, the amount of the carboxyl group-containing vinyl monomer used when copolymerizing the carboxyl group-containing (meth) acrylic acid ester copolymer is in the range of 0.1 to 50% by weight with respect to 100% by weight of the total monomer components. It is preferable that it is a value within.
This is because, by controlling the amount of the carboxyl group-containing vinyl monomer, the polymerization of the (meth) acrylic acid ester copolymer is facilitated and the (meth) acrylic acid ester copolymer is used. This is because the reactivity of the hydrolyzable silyl group and the adhesive property of the adhesive composition can be stably improved.
Therefore, the amount of the carboxyl group-containing vinyl monomer used when copolymerizing the (meth) acrylic acid ester copolymer is a value within the range of 1 to 30% by weight with respect to 100% by weight of the total monomer components. More preferred is a value within the range of 3 to 15% by weight.

Moreover, it is preferable that the acid value of a carboxyl group-containing (meth) acrylic acid ester copolymer is a value within the range of 20-200 KOHmg / g.
This is because the pressure-sensitive adhesive properties of the pressure-sensitive adhesive composition can be stably improved when the acid value of the carboxyl group-containing (meth) acrylic acid ester copolymer is within this range.
That is, when the acid value of the carboxyl group-containing (meth) acrylic acid ester copolymer is a value of 20 KOHmg / g or more, good release characteristics from the release sheet can be obtained, and good adhesion to the adherend. This is because of the expression. On the other hand, if the acid value of the carboxyl group-containing (meth) acrylic acid ester copolymer is a value of 200 KOHmg / g or less, the durability of the pressure-sensitive adhesive composition is improved.
Therefore, the acid value of the carboxyl group-containing (meth) acrylic acid ester copolymer is more preferably a value within the range of 30 to 100 KOHmg / g.
In the present invention, the acid value of the carboxyl group-containing (meth) acrylic acid ester copolymer means that the carboxyl group-containing (meth) acrylic acid ester copolymer is blended with the pressure-sensitive adhesive composition. It means an acid value measured by dissolving a (meth) acrylic acid ester copolymer in a solvent.

(1) -2. Nonfunctional (meth) acrylic acid ester polymer In addition, the nonfunctional (meth) acrylic acid ester polymer has a carboxyl group, a hydroxy group, an epoxy group, an alkoxysilyl group in the molecule of the (meth) acrylic acid ester polymer, It means that it has substantially no functional group such as a long-chain alkyl group, an amide group or an imide group.

More specifically, the monomer constituting the non-functional (meth) acrylic acid ester polymer is preferably a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 20 carbon atoms, such as (meth) acrylic. Methyl methacrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylic acid Examples include 2-ethylhexyl, isooctyl (meth) acrylate, decyl (meth) acrylate and dodecyl (meth) acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate, and stearyl (meth) acrylate. It is done.
These monomers may be used alone or in combination of two or more.

(2) Manufacturing method Moreover, as a manufacturing method of a carboxyl group-containing (meth) acrylic acid ester copolymer or a nonfunctional (meth) acrylic acid ester polymer, for example, a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, It can be produced by a known method such as a suspension polymerization method. In general, a polymerization initiator is used in the production of a carboxyl group-containing (meth) acrylic acid ester copolymer or a non-functional (meth) acrylic acid ester polymer. It is preferable that the compounding quantity of a polymerization initiator is a value within the range of 0.001-5 weight part with respect to a total of 100 weight part of all the monomers.
Moreover, as a polymerization initiator, a thermal polymerization initiator, a photopolymerization initiator, or the like is used. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone. Examples of the thermal polymerization initiator include organic peroxides and inorganic peroxides.

Moreover, it is also preferable to use a commercial item as a carboxyl group-containing (meth) acrylic acid ester copolymer, for example, UC-3000 series by Toagosei Co., Ltd. can be used conveniently.
Moreover, it is also preferable to use a commercial item as a nonfunctional (meth) acrylic acid ester polymer, for example, UP-1000 series by Toagosei Co., Ltd. can be used conveniently.

(3) Weight average molecular weight Moreover, it is preferable that the weight average molecular weight of the (meth) acrylic acid ester polymer which is (B) component is a value within the range of 800-3,000,000.
This is because when the weight average molecular weight of the (meth) acrylic acid ester polymer is a value of 800 or more, the adhesive properties of the adhesive composition are improved, and contamination of the adherend can be suppressed.
On the other hand, if the weight average molecular weight of the (meth) acrylic acid ester polymer is a value of 3,000,000 or less, the compatibility with the terminal silyl group polymer as the component (A) can be maintained, and the polymerization time can be maintained. Furthermore, since it becomes difficult to decompose into low molecular weight substances, contamination of the adherend can be suppressed.
Therefore, it is more preferable that the weight average molecular weight of the (meth) acrylic acid ester polymer as the component (B) is a value within the range of 1,000 to 2,000,000, and 2,000 to 1,800, More preferably, the value is within a range of 000.

(4) Compounding quantity Moreover, the compounding quantity of the (meth) acrylic acid ester polymer which is (B) component is 0.1-150 weight part with respect to 100 weight part of terminal silyl group polymers which are (A) component. A value within the range is preferred.
The reason for this is that a pressure-sensitive adhesive composition having an excellent balance between low peelability and good constant loadability is obtained when the blending amount of the (meth) acrylic acid ester polymer is within such a range. Because it can.
That is, when the amount of the (meth) acrylic acid ester polymer becomes a value of 0.1 parts by weight or more, the reactivity of the hydrolyzable silyl group is improved, so that the cohesive strength of the pressure-sensitive adhesive composition is suitable. This is because it is easy to set the value within the range.
On the other hand, if the amount of the (meth) acrylic acid ester polymer is 150 parts by weight or less, good adhesive properties can be obtained in the adhesive composition.
Accordingly, the blending amount of the (meth) acrylic acid ester polymer as the component (B) is a value within the range of 1 to 120 parts by weight with respect to 100 parts by weight of the terminal silyl group polymer as the component (A). The value is more preferably 4 to 100 parts by weight.

3. Component (C): Tackifier resin (1) type The type of tackifier resin is not particularly limited, and rosin resins such as polymerized rosin, polymerized rosin ester, and rosin derivative, polyterpene resin, aromatic modification Terpene resins and hydrides thereof, terpene phenol resins, coumarone / indene resins, aliphatic petroleum resins, aromatic petroleum resins and hydrides thereof, aliphatic / aromatic copolymer petroleum resins, partially hydrogenated terpene phenols One kind alone or a combination of two or more kinds such as a low molecular mass coalescence of resin, styrene, or substituted styrene can be used.
The reason for this is that if these tackifying resins are used, the adhesive composition has excellent adhesive strength and cohesive strength without inhibiting the interaction with the predetermined terminal silyl group polymer as component (A). This is because it can be given.

In addition, it is more preferable that tackifying resin is a terpene phenol-type resin, and it is still more preferable that it is a fully hydrogenated terpene phenol-type resin and a partially hydrogenated terpene phenol-type resin.
This is because the glass transition point of the terminal silyl group polymer as the component (A) can be easily adjusted by including the terpene phenol resin.
Further, if it is a fully hydrogenated terpene phenol resin or a partially hydrogenated terpene phenol resin, the maximum value of the loss tangent in the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer, that is, the glass transition point can be adjusted relatively high. This is because, even when the cohesive force in the pressure-sensitive adhesive composition is a relatively high value, a good constant load property can be obtained.

Here, the fully hydrogenated terpene phenol resin is a tackifying resin obtained by substantially completely hydrogenating a terpene phenol resin, and the partially hydrogenated terpene phenol resin is a terpene phenol resin. It is a tackifier resin obtained by partially hydrogenating.
The terpene phenol resin has a terpene-derived double bond and a phenol-derived aromatic ring double bond.
Therefore, the fully hydrogenated terpene phenol resin means a tackifying resin in which both the terpene moiety and the phenol moiety are completely or almost hydrogenated, and the partially hydrogenated terpene phenol resin is This means a terpene phenolic resin in which the degree of hydrogenation is not complete and partial.

In addition, it can be judged using the FT-IR spectrum obtained by a Fourier-transform infrared spectrophotometer (FT-IR) whether it corresponds to a fully hydrogenated terpene phenol-type resin.
Here, it demonstrates more concretely using the FT-IR spectrum of the fully hydrogenated terpene phenol-type resin shown in FIG.2 (b).
Here, when the height of the peak of about 2960 cm ⁻¹ derived from the carbon-hydrogen bond stretching vibration of the methyl group is 100, 1625-1575 cm derived from the aromatic carbon-carbon double bond stretching vibration of the phenol moiety. ^If the peak height of ^-1 is less than 20%, the phenolic moiety is completely or almost hydrogenated.
On the other hand, when the peak height derived from the phenol moiety is 20% or more, it is a non-hydrogenated terpene phenol resin in which the phenol moiety and the terpene moiety are hardly hydrogenated as shown in FIG. to decide.
The hydrogenation method and reaction mode are not particularly limited, and examples of the completely hydrogenated terpene phenol resin include NH, manufactured by Yasuhara Chemical Co., Ltd., and the like.

(2) Compounding quantity Moreover, the compounding quantity of tackifying resin which is (C) component is a value within the range of 50-140 weight part with respect to 100 weight part of terminal silyl group polymers which are (A) component. It is preferable.
The reason for this is that a pressure-sensitive adhesive composition excellent in the balance between the adhesive force and the cohesive force can be obtained when the blending amount of the tackifying resin is within such a range.
That is, when the amount of the tackifying resin is 50 parts by weight or more, sufficient adhesive strength can be obtained.
On the other hand, if the amount of the tackifying resin is 140 parts by weight or less, the cohesive force is improved, and when the pressure-sensitive adhesive sheet is processed into a roll shape, the pressure-sensitive adhesive composition is prevented from leaching over time. This is because it can.
Therefore, the compounding amount of the tackifying resin as the component (C) is more preferably a value within the range of 60 to 130 parts by weight with respect to 100 parts by weight of the terminal silyl group polymer as the component (A). More preferably, the value is within the range of 70 to 120 parts by weight.

4). (D) Component: Curing Catalyst (1) Type In addition, a curing catalyst (component (D)) for reacting a hydrolyzable silyl group is basically unnecessary for constituting the pressure-sensitive adhesive composition. When blending such a curing catalyst, the curing catalyst is preferably at least one selected from the group consisting of an aluminum catalyst, a titanium catalyst, a zirconium catalyst, and a boron trifluoride catalyst.
The reason for this is that if these curing catalysts are used, the crosslinking density between the terminal silyl group polymers as the component (A) can be easily controlled, and the adhesive force and cohesive force in the adhesive composition after curing can be controlled. This is because the balance can be further improved.

More specifically, the aluminum catalyst is preferably an aluminum alkoxide, an aluminum chelate, or aluminum (III) chloride.
The titanium-based catalyst is preferably titanium alkoxide, titanium chelate, or titanium (IV) chloride.
Further, as the zirconium-based catalyst, zirconium alkoxide, zirconium chelate, and zirconium (IV) chloride are preferable.
Furthermore, as the boron trifluoride-based catalyst, an amine complex or an alcohol complex of boron trifluoride is preferable.

(2) Blending amount The curing catalyst as component (D) may not be blended, that is, it may be 0. However, when blending to promote the curing reaction, the blending amount is: It is preferable that the value is greater than 0 and 0.1% by weight or less with respect to the total amount of components (A) to (C).
The reason for this is that if the blending amount is a value of 0.1% by weight or less, the catalytic action can be suitably exerted, the adhesive composition can be suitably cured after being applied to a substrate or the like, and is economical. Is advantageous.
Therefore, when the curing catalyst as component (D) is blended, the blending amount is greater than 0 and not more than 0.01% by weight with respect to the total amount of components (A) to (C). Is more preferable, and it is more preferable that the value be greater than 0 and 0.001% by weight or less.

5). (E) Component: Silane Coupling Agent (1) Type Moreover, in constituting the pressure-sensitive adhesive composition, the pressure-sensitive adhesive composition preferably contains a silane coupling agent as the component (E).
The reason for this is that by adding a predetermined amount of the silane coupling agent, the adhesive strength and moisture resistance of the pressure-sensitive adhesive composition can be improved, and the effect of the terminal silyl group polymer as a crosslinking aid can be exhibited. This is because there are cases.
And in order to exhibit the effect as a crosslinking adjuvant effectively, it is more preferable to use the silane coupling agent which has an amino group among various silane coupling agents.
The reason for this is that if it is a silane coupling agent having such an amino group, the effect of the terminal silyl group polymer as a crosslinking aid can be stably exhibited, and as a result, the cohesive strength of the pressure-sensitive adhesive composition can be further improved. It is because it can be adjusted to.
Therefore, as a suitable silane coupling agent having an amino group, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2 -(Aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, etc. The combination of is mentioned.

(2) Blending amount In blending the silane coupling agent as the component (E), the blending amount of the silane coupling agent is 0.1 parts per 100 parts by weight of the terminal silyl group polymer as the component (A). A value within the range of 01 to 1.0 parts by weight is preferred.
This is because, within such a range, a relatively inexpensive pressure-sensitive adhesive composition can be provided, and the pressure-sensitive adhesive strength and transparency of the pressure-sensitive adhesive composition can be stably improved.

6). Various additives Further, in the adhesive composition, as components other than those described above, for example, anti-aging agents, dehydrating agents such as vinylsilane compounds and calcium oxide, fillers, conductive materials, thermally conductive materials, plasticizers, Thickening agents such as anhydrous silica and amide wax, diluents such as isoparaffin, flame retardants such as aluminum hydroxide, halogen flame retardants, phosphorus flame retardants, silicone flame retardants, silicone alkoxy oligomers, pigments, titanate coupling agents It is also preferable to add and mix an aluminum coupling agent, drying oil and the like.
In addition, when these additives are added, although depending on the type of the additive, it is preferable to mix the additives so as not to impair the effects of the present invention. It is preferably a value within the range of 0.01 to 200 parts by weight, preferably a value within the range of 0.01 to 100 parts by weight, with respect to 100 parts by weight of the silyl group polymer. A value within the range of 40 parts by weight is particularly preferred.

7). Gel fraction Moreover, when comprising an adhesive composition, it is preferable that the gel fraction of an adhesive composition is a value within the range of 20 to 70%.
The reason for this is that the gel fraction of the pressure-sensitive adhesive composition is a value within such a range that it can exhibit an excellent cohesive force, and when the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive layer is processed into a roll shape This is because the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer can be prevented from oozing out from the side surface over time.
That is, when the gel fraction of the pressure-sensitive adhesive composition reaches a value of 20% or more, the cohesive force is improved, and when processed into a roll, the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer immerses from the side surface over time. It is because it can suppress coming out.
On the other hand, if the gel fraction of the pressure-sensitive adhesive composition is 70% or less, sufficient adhesive strength can be obtained.
Therefore, the gel fraction of the pressure-sensitive adhesive composition is more preferably a value within the range of 30 to 65%, and still more preferably a value within the range of 35 to 60%.
The “gel fraction of the pressure-sensitive adhesive composition” means, as specifically described in Example 1, after the pressure-sensitive adhesive composition was applied to the base material, at 23 ° C. and 50% RH environment. It means the gel fraction calculated by the dipping method using the pressure-sensitive adhesive after seasoning as a measurement sample after seasoning for 1 week below.

[Second Embodiment]
2nd Embodiment is an adhesive sheet characterized by having an adhesive layer which consists of an adhesive composition as described in the above-mentioned 1st Embodiment.
Hereinafter, the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer can have the same contents as those of the first embodiment, and therefore, mainly on matters relating to the pressure-sensitive adhesive sheet, FIGS. 3 (a) to 3 (d) and the like. A specific description will be given with reference to FIG.

1. Aspects Various aspects can be adopted as the pressure-sensitive adhesive sheet of the present invention. For example, as shown in FIG. 3 (a), the pressure-sensitive adhesive layer 12 made of the pressure-sensitive adhesive composition of the present invention is formed on one side of the substrate 10, It is preferable to set it as the aspect of the single-sided adhesive sheet 50 provided with the peeling sheet 14 in the surface on the opposite side to the base material 10 of the adhesive layer 12. FIG.
If it is an aspect of such an adhesive sheet 50, it can process into an adhesive tape, a display label, or a surface protection adhesive sheet etc., and can apply it to various uses.
Moreover, as shown in FIG.3 (b), the adhesive layer 12 (12a, 12b) which consists of an adhesive composition of this invention is formed in both surfaces of the base material 10, and also the base material 10 and the other side are further provided. It is also preferable to adopt an embodiment of a double-sided pressure-sensitive adhesive sheet 52 having release sheets 14a and 14b on the surface.
If it is an aspect of such an adhesive sheet 52, it can apply suitably for uses, such as conveyance tapes, etc. of an electronic component adhesive material for temporarily fixing an electronic component etc. or an electronic component.

Moreover, as shown in FIG.3 (c), the adhesive layer 12 which consists of an adhesive composition of this invention is formed in one surface of the base material 10, and the adhesion different from this invention is formed in the other surface. Other pressure-sensitive adhesive layers (adhesives) composed of an adhesive composition (including an adhesive composition) such as an acrylic pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, and an epoxy-based adhesive It is preferable that the pressure-sensitive adhesive layers 54 and 18 are formed as a double-sided pressure-sensitive adhesive sheet 54 provided with release sheets 14a and 14b on the surface opposite to the base material 10 of the pressure-sensitive adhesive layers 12 and 18.
If it is the aspect of such an adhesive sheet 54, it can apply suitably for uses, such as a fixing member for fixing an electronic component to a board | substrate.
Furthermore, as shown in FIG.3 (d), the aspect of the double-sided adhesive sheet 56 which did not contain a base material but was equipped with the peeling sheets 14a and 14b on both surfaces of the adhesive layer 12 which consists of an adhesive composition of this invention. It is preferable that
If it is the aspect of such an adhesive sheet 56, it can apply suitably as an adhesive sheet for bonding of the optical member of a display, for example.

2. As described in the first embodiment, the pressure-sensitive adhesive layer comprises at least a predetermined terminal silyl group polymer as the component (A) and a (meth) acrylic ester as the component (B). A pressure-sensitive adhesive composition comprising a polymer and a tackifying resin as the component (C), and the (meth) acrylic acid ester polymer as the component (B) is a carboxyl group-containing (meth) acrylic It consists of an adhesive composition containing an acid ester copolymer and a non-functional (meth) acrylic acid ester polymer or one of them.

(1) -1. In the present invention, the (B) component (meth) acrylic acid ester polymer contains a carboxyl group-containing (meth) acrylic acid ester copolymer. The surface state of the pressure-sensitive adhesive layer and the pressure-sensitive adhesive properties will be described.
That is, in FIG. 4A, the horizontal axis represents 100 parts by weight of the terminal silyl group polymer when a carboxyl group-containing (meth) acrylic acid ester copolymer having a weight average molecular weight of 2000 is used as the component (B). The amount of the carboxyl group-containing (meth) acrylic acid ester copolymer is taken, and the left vertical axis shows carbon atoms and oxygen atoms obtained by XPS analysis (X-ray photoelectron spectroscopy) on the outermost surface of the pressure-sensitive adhesive layer. The concentration is taken, and the right vertical axis shows the silicon atom concentration.
The characteristic curve A is a characteristic curve indicating the carbon atom concentration, the characteristic curve B is a characteristic curve indicating the oxygen concentration, and the characteristic curve C is a characteristic curve indicating the silicon atom concentration.
Similarly, in FIG. 4B, the terminal silyl group in the case where a carboxyl group-containing (meth) acrylate copolymer having a weight average molecular weight of 1,800,000 is used as the component (B) on the horizontal axis. The amount of the carboxyl group-containing (meth) acrylic acid ester copolymer based on 100 parts by weight of the polymer is taken, and the left vertical axis shows the atomic concentrations of carbon atoms and oxygen atoms obtained by XPS analysis on the outermost surface of the pressure-sensitive adhesive layer. The right vertical axis shows the silicon atom concentration.
The characteristic curve D is a characteristic curve indicating the carbon atom concentration, the characteristic curve E is a characteristic curve indicating the oxygen concentration, and the characteristic curve F is a characteristic curve indicating the silicon atom concentration.
In FIG. 4C, the horizontal axis represents the blending amount of the carboxyl group-containing (meth) acrylic acid ester copolymer with respect to 100 parts by weight of the terminal silyl group polymer, and the vertical axis represents adhesion by XPS elemental analysis measurement. The pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the (meth) acrylate polymer as the component (B) from the pressure-sensitive adhesive composition, wherein the silicon element concentration on the surface of the pressure-sensitive adhesive layer of the sheet is Z ₁ The silicon concentration change rate Z represented by the following general formula (A) is shown by taking the silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement as Z ₀ .

  Moreover, the characteristic curve G is a characteristic curve about the silicon element concentration change rate about the carboxyl group containing (meth) acrylic acid ester copolymer of the weight average molecular weight 2000, and the characteristic curve H is a carboxyl with a weight average molecular weight of 1,800,000. It is a characteristic curve about the silicon element density | concentration change rate about a group containing (meth) acrylic acid ester copolymer.

4 (a) to 4 (c), the silicon atom concentration and the oxygen atom concentration hardly change with the increase in the amount of the carboxyl group-containing (meth) acrylic acid ester copolymer. It is understood that the atomic concentration is decreasing.
That is, the silicon atom concentration is derived from the terminal silyl group polymer as the component (A), and the decrease in the silicon atom concentration means that the concentration of the surface terminal silyl group polymer is decreased. In other words, it means that the carboxyl group-containing (meth) acrylic ester copolymer is segregated in the pressure-sensitive adhesive layer on the surface side opposite to the substrate.
Therefore, when the pressure-sensitive adhesive composition contains a carboxyl group-containing (meth) acrylic acid ester copolymer, the carboxyl group-containing (meth) acrylic acid ester copolymer becomes a pressure-sensitive adhesive over time after being applied to the substrate. It is understood that the layer tends to segregate on the surface side (release sheet side) opposite to the substrate.
In addition, the analysis method of XPS analysis can be calculated by performing elemental analysis of a predetermined area on the outermost surface of the pressure-sensitive adhesive layer using an XPS measurement device, as specifically described in Example 1. .

FIG. 5 shows the relationship between the state of the surface of the pressure-sensitive adhesive layer on the side opposite to the substrate and the pressure-sensitive adhesive properties when a carboxyl group-containing (meth) acrylic acid ester copolymer is used.
More specifically, the horizontal axis in FIG. 5 represents the silicon atom concentration change rate described above, and the vertical axis represents the low-speed peeling force from the release sheet.
That is, from the characteristic curve R, as the silicon atom concentration near the surface of the pressure-sensitive adhesive layer decreases at the interface between the pressure-sensitive adhesive layer and the release sheet, that is, in the vicinity of the surface, the carboxyl group-containing (meth) acrylic acid copolymer It will be understood that the release from the release sheet becomes easier as the coalescence segregates more relatively.
In addition, in Example 1, the low-speed peeling force from the peeling sheet of an adhesive sheet is measured using a 180 degree tensile tester so that it may demonstrate concretely.

(1) -2. Pressure-sensitive adhesive sheet containing a non-functional (meth) acrylic acid ester polymer In the present invention, the pressure-sensitive adhesive when the (meth) acrylic acid ester polymer of the component (B) contains a non-functional (meth) acrylic acid ester polymer The surface state and adhesive properties of the agent layer will be described.
That is, in FIG. 6 (a), the horizontal axis represents nonfunctionality (100 parts by weight with respect to 100 parts by weight of the terminal silyl group polymer when a nonfunctional (meth) acrylic acid ester polymer having a weight average molecular weight of 6000 is used as the component (B). Taking the compounding amount of the (meth) acrylic acid ester polymer, the left vertical axis represents the atomic concentration of carbon atoms and oxygen atoms obtained by XPS analysis on the outermost surface of the pressure-sensitive adhesive layer, and the right vertical axis represents the silicon atom concentration Is shown.
The characteristic curve I is a characteristic curve indicating the carbon atom concentration, the characteristic curve J is a characteristic curve indicating the oxygen concentration, and the characteristic curve K is a characteristic curve indicating the silicon atom concentration.
Similarly, in FIG. 6B, the weight of the terminal silyl group polymer in the case where a non-functional (meth) acrylate polymer having a weight average molecular weight of 330,000 is used as the component (B) on the horizontal axis is 100 weight. The amount of the non-functional (meth) acrylic acid ester polymer with respect to the part is taken, the left vertical axis is the atomic concentration of carbon atoms and oxygen atoms obtained by XPS analysis on the outermost surface of the pressure-sensitive adhesive layer, the right vertical axis The figure shows the silicon atom concentration.
The characteristic curve L is a characteristic curve indicating the carbon atom concentration, the characteristic curve M is a characteristic curve indicating the oxygen concentration, and the characteristic curve N is a characteristic curve indicating the silicon atom concentration.
In FIG. 6 (c), the horizontal axis represents the amount of the non-functional (meth) acrylic acid ester polymer based on 100 parts by weight of the terminal silyl group polymer, and the vertical axis represents the pressure-sensitive adhesive sheet obtained by XPS elemental analysis measurement. The silicon concentration change rate Z on the surface of the pressure-sensitive adhesive layer is shown.
Moreover, the characteristic curve O is a characteristic curve about the silicon element density | concentration change rate about the nonfunctional (meth) acrylic acid ester polymer of the weight average molecular weight 6000, and the characteristic curve P is a nonfunctional (weight-average molecular weight 330,000 nonfunctional ( It is a characteristic curve about the silicon element concentration change rate about a meth) acrylic acid ester polymer.

6 (a) to 6 (c), the silicon atom concentration is almost unchanged even though the carbon atom concentration and the oxygen atom concentration are hardly changed as the amount of the non-functional (meth) acrylic acid ester polymer is increased. It is understood that is decreasing.
That is, as in the case of the carboxyl group-containing (meth) acrylic acid ester copolymer, the non-functional (meth) acrylic acid ester polymer is segregated on the surface side opposite to the substrate in the pressure-sensitive adhesive layer. It means that.
Therefore, when the pressure-sensitive adhesive composition contains a non-functional (meth) acrylic acid ester polymer, after application to the substrate, over time, the non-functional (meth) acrylic acid ester polymer is in the pressure-sensitive adhesive layer. It is understood that the surface side opposite to the substrate tends to segregate.

(2) the silicon concentration change rate also silicon element concentration of the surface of the adhesive layer of the adhesive sheet according to elemental analysis of the above XPS and Z _1, from the adhesive composition (B) as component (meth) acrylic acid It is represented by the following general formula (A) when the silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the ester polymer is Z _0. The silicon concentration change rate Z is preferably 83% or less.

That is, if the silicon concentration change rate Z is a value of 83% or less, the (meth) acrylic acid ester polymer as the component (B) is segregated on the surface side opposite to the substrate in the pressure-sensitive adhesive layer. This is because it can be determined and the surface state of the pressure-sensitive adhesive layer can be suitably defined.
More specifically, when the silicon concentration change rate exceeds 83%, it means that there are many predetermined terminal silyl group polymers on the surface side of the pressure-sensitive adhesive layer. This is because it may be difficult or suitable constant load properties may not be obtained. On the other hand, if the rate of change in the silicon concentration is too low, the configuration of the entire pressure-sensitive adhesive layer changes and good adhesive properties are obtained. This is because there is a case that cannot be obtained.
Therefore, the silicon concentration change rate is more preferably a value within the range of 60 to 83%, and still more preferably a value within the range of 62 to 82%.

(3) Thickness The thickness of the pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition is usually preferably a value in the range of 1 to 100 μm, more preferably a value in the range of 5 to 50 μm. preferable.
The reason for this is that when the thickness of the pressure-sensitive adhesive layer is less than 1 μm, sufficient pressure-sensitive adhesive properties may not be obtained, and conversely, when the thickness of the pressure-sensitive adhesive layer exceeds 100 μm, the residual solvent increases. This is because the adhesive properties and the like are likely to change.

3. Type of base material (1) Here, as the base material for forming the pressure-sensitive adhesive layer, for example, polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyimide, polyether imide, polyether ketone, polyether ether Resins such as ketone, polycarbonate, polymethyl methacrylate, triacetyl cellulose, polynorbornene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, vinyl chloride, polyurethane acrylate, polyether sulfone, polyphenyl ether sulfone A resin film made of is preferably mentioned.

(2) Thickness Further, the thickness of the substrate is not particularly limited, but it is usually preferably a value in the range of 1 to 1,000 μm, and a value in the range of 10 to 100 μm. More preferably.

4). Release sheet (release substrate)
Moreover, it is also preferable that the adhesive sheet of this invention is an aspect by which peeling sheet (peeling base material) 14, 14a, 14b is bonded with respect to the surface of an adhesive layer.
Examples of the release sheet include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene. Moreover, what provided the peeling layer by apply | coating peeling agents, such as a silicone resin, a fluorine resin, a long-chain alkyl acrylate resin, and a rubber-type resin, to these peeling sheets is also mentioned.
Moreover, it is preferable that the thickness of this peeling sheet is a value within the range of 20-150 micrometers normally.
In addition, by providing a predetermined difference in the peeling force between the two peeling sheets, it is possible to prevent the pressure-sensitive adhesive layer from following partly when the peeling sheet having the lower peeling force is peeled off. .

[Third Embodiment]
3rd Embodiment is a manufacturing method of the adhesive sheet which provided the adhesive layer which consists of an adhesive composition in both surfaces or one side of a base material, and was provided with the peeling sheet in the surface on the opposite side to the base material of the said adhesive layer. And it is a manufacturing method of the adhesive sheet characterized by including following process (1)-(3).
(1) A pressure-sensitive adhesive composition comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifying resin as the component (C). The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, and has a urethane bond and / or a urea bond in a part of the main chain or a side chain. Furthermore, it has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain, and the (meth) acrylate polymer as the component (B) contains a carboxyl group ( meth) one acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or either only contains, and, (C) a tackifier resin as component, fully hydrogenated terpene phenol Preparing a fat and a pressure-sensitive adhesive composition

(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)

(2) A step of laminating the pressure-sensitive adhesive composition on both sides or one side of the substrate and forming a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a non-cured pressure-sensitive adhesive composition (3) heating the pressure-sensitive adhesive composition From the pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a cured pressure-sensitive adhesive composition, the silicon element concentration of the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet measured by XPS elemental analysis as Z ₁ , The silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the (meth) acrylic acid ester polymer as the component (B) is Z ₀ . When the silicon concentration change rate Z represented by the following general formula (A) is 83% or less,

  Hereinafter, the manufacturing method of the adhesive sheet of 3rd Embodiment is demonstrated concretely.

1. Step (1) (Preparation step of pressure-sensitive adhesive composition)
Step (1) is a pressure-sensitive adhesive composition comprising a terminal silyl group polymer as component (A), a (meth) acrylic acid ester polymer as component (B), and a tackifying resin as component (C). It is a step of preparing an object.
Here, with reference to Fig.1 (a), the synthesis example of the terminal silyl group polymer which is (A) component is shown.
First, in FIG. 1A, a urethane prepolymer (diisocyanate compound) having an isocyanate group at the end of the main chain or side chain of the molecule represented by the formula (1) is prepared.
Next, in FIG. 1 (a), an active hydrogen group capable of reacting with an isocyanate group is present at one end of the molecule represented by formula (2), and the other end of the molecule is represented by general formula (1). A silylating agent having a hydrolyzable silyl group is prepared.
Next, after uniformly mixing the urethane prepolymer represented by the formula (1) and the silylating agent represented by the formula (2), for example, by heating and reacting under a nitrogen atmosphere at 80 ° C. for 1 hour, A terminal silyl group polymer represented by the formula (3) can be obtained.
As shown in FIG. 1 (b), the terminal silyl group polymer represented by the formula (3) passes through hydrolysis of the hydrolyzable silyl group represented by the general formula (1), and is further cured by dehydration condensation. As the reaction proceeds, a three-dimensional network structure can be formed.

In synthesizing the terminal silyl group polymer represented by the formula (3), the silylating agent has an isocyanate group and a predetermined polymer skeleton, contrary to the case of FIG. The compound which has may have an active hydrogen group.
In addition, the active hydrogen in the urethane bond or urea bond introduced into the main chain or side chain of the predetermined terminal silyl group polymer may be substituted with an organic group as described in the first embodiment.
Therefore, allophanate bonds are also included in the category of urethane bonds, and burette bonds are also included in the category of urea bonds.

Next, after optionally diluting the terminal silyl group polymer as the component (A) with a diluting solvent, a predetermined amount of the (meth) acrylate polymer as the component (B) is added under stirring conditions, Make a uniform mixture.
Next, a predetermined amount of a tackifier resin as component (C), a curing catalyst as component (D), and other additives are respectively added to the obtained mixed solution and stirred until uniform. Further, a pressure-sensitive adhesive composition solution can be obtained by further adding a diluting solvent as necessary so as to obtain a desired viscosity.

2. Step (2) (Lamination step of non-curing pressure-sensitive adhesive composition)
Step (2) is a step of laminating the obtained pressure-sensitive adhesive composition on both sides or one side of the substrate to form a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer made of a non-cured pressure-sensitive adhesive composition.
In addition, as a method of laminating the pressure-sensitive adhesive composition, for example, there is a method in which the pressure-sensitive adhesive composition solution is applied by a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like. Can be mentioned. And after apply | coating an adhesive composition solution and forming an application layer, it is preferable to scatter and dry a solvent.
At this time, it is preferable that the thickness of a coating layer is a value within the range of 1-100 micrometers, and it is more preferable that it is a value within the range of 5-50 micrometers.
This is because if the coating layer is too thin, sufficient adhesive properties and the like may not be obtained. Conversely, if it is too thick, the residual solvent may cause a problem.
Moreover, as drying conditions, it is usually preferable to be within a range of 10 seconds to 10 minutes at 50 to 150 ° C.

3. Step (3) (Hardening step of pressure-sensitive adhesive layer comprising non-cured pressure-sensitive adhesive composition)
Step (3) is a step of heating the pressure-sensitive adhesive composition to obtain a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer made of a cured pressure-sensitive adhesive composition.
That is, it is preferable to heat-treat in the state which laminated | stacked the peeling sheet on the surface of the application layer of the state dried on the base material, and to make it harden-react and to make it an adhesive layer.
Alternatively, the application layer of the pressure-sensitive adhesive composition laminated on the release sheet may be preliminarily cured by heat treatment to form a pressure-sensitive adhesive layer, and then laminated on the substrate by a transfer method.
Furthermore, it is also preferable to heat-treat the coating layer formed on the substrate without using a release sheet, thereby causing a curing reaction to form an adhesive layer.

In addition, the curing reaction in the coating layer of the pressure-sensitive adhesive composition is performed through the drying process and the seasoning process described above.
That is, as a condition of the seasoning step, the storage temperature is 10 to 35 from the viewpoint of uniformly curing the coating layer of the pressure-sensitive adhesive composition without damaging the coating layer or the base material of the pressure-sensitive adhesive composition. It is preferable that it is degree C, and it is more preferable that it is 23-30 degreeC.
Moreover, as humidity at the time of heating, it is preferable that it is 30 to 75% RH, and it is more preferable that it is 45 to 65% RH.

4). Process (4) (Attaching process)
Although it is an optional step, it is a step of bonding the finally obtained pressure-sensitive adhesive sheet to an adherend.
For example, first, after peeling off the release sheet laminated on the pressure-sensitive adhesive layer, with the surface of the pressure-sensitive adhesive layer facing the adherend, using a laminator or a pressure roll at a predetermined pressure It is preferable to bond uniformly by pressing.

By manufacturing in this way, the adhesive sheet which consists of an adhesive composition containing a predetermined terminal silyl group polymer, a predetermined (meth) acrylic acid ester polymer, and a tackifier resin can be efficiently manufactured.
The pressure-sensitive adhesive sheet of the present invention includes a terminal silyl group polymer as the component (A) in the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer, and thus has a predetermined flexibility and adherend. It has a good affinity for, and has the feature that it can be attached so as to be moistened without involving air or the like.

[Fourth Embodiment]
4th Embodiment is a manufacturing method of the adhesive sheet which was not provided with the base material but was equipped with the adhesive layer which consists of an adhesive composition, and was equipped with the peeling sheet on both surfaces of the said adhesive layer, Comprising: )-(3)
It is a manufacturing method of the adhesive sheet characterized by including.
(1) A pressure-sensitive adhesive composition comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifying resin as the component (C). The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, and has a urethane bond and / or a urea bond in a part of the main chain or a side chain. Furthermore, it has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain, and the (meth) acrylate polymer as the component (B) contains a carboxyl group ( meth) one acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or either only contains, and, (C) a tackifier resin as component, fully hydrogenated terpene phenol Preparing a fat and a pressure-sensitive adhesive composition

(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)

(2) Step of forming a pressure-sensitive adhesive sheet with a pressure-sensitive adhesive layer comprising a non-cured pressure-sensitive adhesive composition by laminating the pressure-sensitive adhesive composition on the surface of the release sheet (3) heating and curing the pressure-sensitive adhesive composition From the pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet comprising a pressure- sensitive adhesive composition is used, and the silicon element concentration on the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet measured by XPS elemental analysis is Z _1. ) when the (meth) silicon element concentration of the surface of the pressure-sensitive adhesive layer according to the XPS elemental analysis of the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive composition was prepared except the acrylic acid ester polymer as a component and a Z ₀ And the silicon concentration change rate Z represented by the following general formula (A) is 83% or less.

That is, by manufacturing in this way, even if it is a case where a base material is not included, a predetermined | prescribed adhesive sheet can be manufactured efficiently.
In addition, in the process (2), except the process of apply | coating an adhesive composition to the surface of a peeling sheet and forming an application layer, it is the same as the manufacturing method of the adhesive sheet containing the base material which is 3rd Embodiment. Therefore, specific description is omitted.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further in detail, the range of this invention is not limited by these Examples etc. without a particular reason.

[Example 1]
1. Preparation of pressure-sensitive adhesive composition (1) Preparation of silylating agent A reaction vessel equipped with a stirrer was charged with 206 parts by weight of N-aminoethyl-γ-aminopropylmethyldimethoxysilane and 172 parts by weight of methyl acrylate. The mixture was heated and reacted at 80 ° C. for 10 hours with stirring in a nitrogen atmosphere to obtain a silylating agent.

(2) Preparation of urethane prepolymer In a reaction vessel with a stirrer, polyoxypropylene diol (Asahi Glass Co., Ltd., PML S4015, weight average molecular weight 15,000) 1000 parts by weight and isophorone diisocyanate 24.6 parts by weight (NCO / OH ratio = 1.7) and 0.05 part by weight of dibutyltin dilaurate were added and heated under a nitrogen atmosphere with stirring at 85 ° C. for 7 hours to obtain a urethane prepolymer (diisocyanate). Compound) was obtained.

(3) Preparation of terminal silyl group polymer In a reaction vessel equipped with a stirrer, 1000 parts by weight of the obtained urethane prepolymer and 42.1 parts by weight of the obtained silylating agent were housed, and in a nitrogen atmosphere, While stirring, heat treatment was performed at 80 ° C. for 1 hour to obtain a terminal silyl group polymer.
At this time, the disappearance of isocyanate group absorption (2265 cm ⁻¹ ) was observed using a Fourier transform infrared spectrophotometer (FT-IR), thereby confirming the progress of the reaction.
The obtained terminal silyl group polymer is a both-end silyl group polymer having a terminal moiety represented by the following formula (9) at both ends of polyoxypropylene as a main chain and having a weight average molecular weight of 40,000. there were.
Further, by using N-aminoethyl-γ-aminopropylmethyldimethoxysilane as a raw material for the silylating agent, a bifunctional terminal silyl group was introduced into the obtained terminal silyl group polymer.

(4) Preparation of pressure-sensitive adhesive composition Next, 100 parts by weight of terminal silyl group polymer and acrylate ester copolymer UC-3510 (manufactured by Toagosei Co., Ltd., carboxyl group-containing, molecular weight in solid content) 2000, in Table 1 (referred to as (B1)) 5 parts by weight, and fully hydrogenated terpene phenol resin as a tackifier resin (Yasuhara Chemical Co., Ltd., YS Polyster NH, hereinafter simply referred to as “NH”) 100 Part by weight, and stirred in the presence of a predetermined amount of ethyl acetate until uniform to obtain a pressure-sensitive adhesive composition in a solution state.

2. Preparation of pressure-sensitive adhesive sheet Subsequently, the obtained pressure-sensitive adhesive composition in a solution state was applied to one side of a 50 μm-thick polyester film (Lumirror PET50, manufactured by Toray Industries, Inc.) by a knife coater method. Thereafter, heat treatment was performed at 100 ° C. for 1 minute to form an adhesive layer having a thickness of 25 μm.
Thereafter, the pressure-sensitive adhesive layer and a release sheet (SP-PET381130, manufactured by Lintec Corporation, polyethylene terephthalate on which one side was peeled with a silicone-based release agent, a thickness of 38 μm) were bonded to form a pressure-sensitive adhesive sheet. .

3. Seasoning of the pressure-sensitive adhesive sheet Next, the pressure-sensitive adhesive sheet comprising the pressure-sensitive adhesive composition before curing and the base material (polyester film) is allowed to stand for 14 days in a 23 ° C., 50% RH environment (seasoning). Then, the pressure-sensitive adhesive composition was sufficiently cured to obtain a pressure-sensitive adhesive sheet of Example 1, which was subjected to various evaluations.

4). Evaluation (1) Adhesive strength Based on JIS Z0237: 2000, the adhesive strength in an adhesive sheet was measured. That is, after cutting out a test piece having a width of 25 mm and a length of 200 mm from the obtained pressure-sensitive adhesive sheet, removing the release sheet, and bonding to a SUS304 plate (# 360 file processing) using a 2 kgf rubber roller. , 23 ° C. and 50% RH in a standard environment for 24 hours.
Next, using a tensile tester (Orientec Co., Ltd., Tensilon), the test piece was peeled from a SUS304 plate (# 360 file processing) at a tensile speed of 300 mm / min and an angle of 180 °, and measured at this time. The peel strength thus applied was defined as the adhesive strength (N / 25 mm) of the adhesive composition. The obtained results are shown in Table 1.

(2) Low-speed peeling force Based on JIS Z0237: 2000, the peeling force in an adhesive sheet was measured. That is, a test piece having a width of 25 mm and a length of 200 mm was cut out from the obtained pressure-sensitive adhesive sheet, and the pressure-sensitive adhesive sheet of the test piece was fixed in an environment of 23 ° C. and 50% RH, and the release sheet was peeled off at a peeling speed of 300 mm / min. The film was pulled under a condition of 180 ° in the direction, and the peel load measured at this time was defined as the low-speed peel force (N / 25 mm) of the pressure-sensitive adhesive sheet. The obtained results are shown in Table 1.

(3) Constant load property The constant load property in the obtained adhesive sheet was evaluated. That is, a test piece having a width of 25 mm and a length of 100 mm was cut out from the obtained pressure-sensitive adhesive sheet, the release sheet was removed, and a 2 kgf rubber roller was used to remove 50 mm from the edge of the cut-out pressure-sensitive adhesive sheet (25 mm × 50 mm as an area). = 1250 mm ² ) The pressure-sensitive adhesive layer surface was bonded to a SUS # 600 plate and left in a standard environment of 40 ° C. and 50% RH for 1 hour immediately after bonding.
Next, the test piece after being left is placed with the side to which the double-sided pressure-sensitive adhesive sheet is attached facing downward, and a load of 200 g (1.96 N) is applied to the end of the pressure-sensitive adhesive sheet in the vertical (down 90 °) direction, After maintaining the state for 1 hour, the distance (peeling distance, mm) at which the pressure-sensitive adhesive sheet was peeled from the SUS plate surface was measured. The obtained results are shown in Table 1.
In addition, when 1 hour passed from the start of measurement and a test piece peeled completely from the SUS board and fell, it described as "falling" in Table 1.

(4) Surface elemental analysis A carbon atom measured by XPS analysis of the outermost surface of the pressure-sensitive adhesive layer in the obtained pressure-sensitive adhesive sheet under the following conditions using an XPS measurement analyzer (manufactured by ULVAC-PHI, PHI Quantera SXM), Elemental analysis of oxygen and silicon atoms was performed.
Further, from this measurement, the carbon atom concentration, the oxygen atom concentration, and the silicon atom concentration with respect to the total amount of carbon atoms, oxygen atoms, and silicon atoms (100 atom%) were calculated.
Further, the silicon element concentration of the surface of the adhesive layer of the adhesive sheet according to elemental analysis of XPS and Z _1, was prepared except (meth) acrylic acid ester polymer as the component (B) from the pressure-sensitive adhesive composition the adhesive When the silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition is Z ₀ , the silicon concentration change rate Z represented by the following general formula (A) was calculated. The obtained results are shown in Table 1.

X-ray source: Monochromatic ALKα
Output: 25W
Acceleration voltage: 15 kV
Beam diameter: 100 μm
Photoelectron extraction angle: 45 °
Pulse energy: 112 eV (carbon atom, oxygen atom), 224 eV (silicon atom)
Step resolution: 0.1 eV (carbon atom, oxygen atom), 0.2 eV (silicon atom)
Measurement area: 100μmφ

(5) Gel fraction The gel fraction of the pressure-sensitive adhesive composition (the pressure-sensitive adhesive composition after curing through the seasoning process) in the obtained pressure-sensitive adhesive sheet was measured.
That is, the thickness of the pressure-sensitive adhesive composition obtained after drying on the release-treated surface of a release sheet (SP-PET381130, manufactured by Lintec Corporation, polyethylene terephthalate on which one side was peeled off with a silicone-based release agent, thickness 38 μm). Was applied so as to be 25 μm and heated at 100 ° C. for 1 minute to form an adhesive layer. The pressure-sensitive adhesive layer and another release sheet (SP-PET 382120, manufactured by Lintec, polyethylene terephthalate, one side of which is peel-treated with a silicone-based release agent, with a thickness of 38 μm) are bonded to create a pressure-sensitive adhesive sheet. did. The pressure-sensitive adhesive sheet was allowed to stand in an atmosphere of 23 ° C. and 50% RH for 1 week, and then about 0.1 g of the pressure-sensitive adhesive was taken out from the pressure-sensitive adhesive sheet, wrapped in Tetron mesh (# 400), and then ethyl acetate for 120 hours. After the immersion, the gel was dried at 100 ° C. for 30 minutes, the weight before and after the immersion was measured, and the weight was substituted into the following formula (B) to calculate the gel fraction. The obtained results are shown in Table 1.

[Examples 2 to 5]
In Examples 2 to 5, pressure-sensitive adhesive compositions were prepared as described in Table 1, and pressure-sensitive adhesive sheets were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 1.

[Examples 6 to 8]
In Examples 6 to 8, pressure-sensitive adhesive compositions were prepared with the formulations shown in Table 1, and pressure-sensitive adhesive sheets were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 1.
In addition, the acrylate ester copolymer (carboxyl group-containing, molecular weight 1.8 million, referred to as (B2) in Table 1) used in Examples 6 to 8 was synthesized as follows.
That is, after purging the inside of the reaction vessel equipped with a stirrer with nitrogen, as a monomer component, 95 parts by weight of n-butyl acrylate (BA), 5 parts by weight of acrylic acid (AAc), and ethyl acetate as a solvent, And 0.1 part by weight of a polymerization initiator, azbisisobutyronitrile, respectively.
Subsequently, solution polymerization was performed while heating and stirring to obtain an acrylate copolymer (B2) having a weight average molecular weight (GPC measurement) of 1.8 million.
Moreover, the obtained acrylic acid ester copolymer was dissolved in ethyl acetate as a solvent, and the solid content concentration was 16% by weight.

[Examples 9 to 12, Comparative Examples 1 to 6]
In Examples 9 to 12 and Comparative Examples 1 to 6, pressure-sensitive adhesive compositions were prepared as described in Table 1, and pressure-sensitive adhesive sheets were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 1.
In addition, as the (meth) acrylic acid ester polymer, those described below were used.

(B) Type of (meth) acrylic acid ester polymer;
(B1) UC-3510, manufactured by Toagosei Co., Ltd., carboxyl group-containing, weight average molecular weight 2000
(B2) BA / AAc = 95/5, carboxyl group-containing, weight average molecular weight 1.8 million (B3) UP-1080, manufactured by Toagosei Co., Ltd., non-functional, weight average molecular weight 6000
(B4) BA = 100, non-functional, weight average molecular weight 330,000 (B5) UG-4010, manufactured by Toagosei Co., Ltd., epoxy group-containing, weight average molecular weight 2900
(B6) UH-2041, manufactured by Toagosei Co., Ltd., hydroxy-containing group, weight average molecular weight 2500
(B7) BA / MA / GMA = 70/10/20, epoxy group-containing, weight average molecular weight 400,000

In Examples using a carboxyl group-containing (meth) acrylic acid ester copolymer or a non-functional (meth) acrylic acid ester polymer, the surface opposite to the base material of the pressure-sensitive adhesive layer was determined by surface analysis of the pressure-sensitive adhesive layer. On the side, it was confirmed that the (meth) acrylic acid ester polymer was unevenly distributed.
Further, in Examples using a carboxyl group-containing (meth) acrylic acid ester copolymer or a non-functional (meth) acrylic acid ester polymer, it has a good low-speed peeling force and a good constant load. Therefore, it was easily peelable from the release sheet, and had good adhesive strength to the adherend.
On the other hand, in the comparative example using the epoxy group- and hydroxy group-containing (meth) acrylic acid ester copolymer, the peel force was a relatively large value, and the constant load property was inferior.

As described above in detail, according to the pressure-sensitive adhesive composition of the present invention and the pressure-sensitive adhesive sheet using the same, a carboxyl group (meth) acrylic acid ester copolymer or a nonfunctional ( By blending a (meth) acrylic acid ester polymer and a tackifier resin, even if the amount of the curing catalyst is small, or even when the curing catalyst is not blended, the good adhesive force is maintained. Excellent constant load properties can be obtained.
Moreover, since the predetermined (meth) acrylic acid ester polymer is segregated near the surface opposite to the base material of the pressure-sensitive adhesive layer, it can be easily peeled from the release sheet.
Therefore, the pressure-sensitive adhesive composition of the present invention and the pressure-sensitive adhesive sheet using the same are expected to be used in various applications such as home appliances, automobiles, and OA equipment.
More specifically, it is expected to be used for laminating resin plates inside electronic devices such as mobile phones and personal computers, and laminating optical recording media, magneto-optical recording media, liquid crystal displays, and touch panel members. Is done.

10: base material, 12, 12a, 12b: adhesive layer, 14, 14a, 14b: release sheet, 18: other adhesive layer, 50: adhesive sheet (single-sided adhesive sheet), 52: adhesive sheet (double-sided adhesive sheet) ), 54: Adhesive sheet (double-sided adhesive sheet with different adhesive layer) 56: Double-sided adhesive sheet without substrate

Claims (11)

A pressure-sensitive adhesive composition comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifier resin as the component (C),
The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, and has a urethane bond and a urea bond, or one of the main chain and a side chain, And having hydrolyzable silyl groups represented by the following general formula (1) at both ends of the main chain,
Wherein (B) as component (meth) acrylic acid ester polymer, see contains one carboxyl group-containing (meth) acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or either,
And the tackifying resin as the component (C) is a fully hydrogenated terpene phenol resin,
The adhesive sheet having an adhesive layer comprising the adhesive composition, the silicon element concentration of the surface of the pressure-sensitive adhesive layer of the adhesive sheet according to elemental analysis of XPS and Z _1, from the adhesive composition (B) the silicon element concentration of the surface of the pressure-sensitive adhesive layer according to the XPS elemental analysis of the pressure-sensitive adhesive sheet having a (meth) pressure-sensitive adhesive composition was prepared except the acrylic acid ester polymer as a component is taken as Z ₀ The pressure-sensitive adhesive composition, wherein the silicon concentration change rate Z represented by the following general formula (A) is 83% or less .
(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)
  The pressure-sensitive adhesive composition according to claim 1, wherein the (meth) acrylic acid ester polymer as the component (B) has a weight average molecular weight in the range of 800 to 3,000,000.   With respect to 100 parts by weight of the terminal silyl group polymer as the component (A), the blending amount of the (meth) acrylic acid ester polymer as the component (B) is within a range of 0.1 to 150 parts by weight. The pressure-sensitive adhesive composition according to claim 1 or 2, wherein the pressure-sensitive adhesive composition is provided.   The blending amount of the tackifying resin as the component (C) is a value within the range of 50 to 140 parts by weight with respect to 100 parts by weight of the terminal silyl group polymer as the component (A). Item 4. The pressure-sensitive adhesive composition according to any one of items 1 to 3.   The pressure-sensitive adhesive according to any one of claims 1 to 4, wherein the terminal silyl group polymer as the component (A) has a weight average molecular weight in the range of 15,000 to 200,000. Composition. The pressure-sensitive adhesive composition according to any one of claims 1 to 5 , wherein the pressure-sensitive adhesive composition has a gel fraction within a range of 20 to 70%. It has an adhesive layer which consists of an adhesive composition in any one of Claims 1-6 , The adhesive sheet characterized by the above-mentioned. The pressure-sensitive adhesive sheet according to claim 7 , wherein the pressure-sensitive adhesive layer is provided on at least one side of the substrate. The pressure-sensitive adhesive sheet according to claim 7 , having a structure in which the pressure-sensitive adhesive layer is sandwiched between two release sheets. A method for producing a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a pressure-sensitive adhesive composition on both sides or one side of a base material, and a release sheet on the surface of the pressure-sensitive adhesive layer opposite to the base material. The manufacturing method of the adhesive sheet characterized by including (1)-(3).
(1) A pressure-sensitive adhesive composition comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifying resin as the component (C). The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain and has a urethane bond and / or a urea bond in a part of the main chain or a side chain. and, further, to both ends of the main chain, it has a hydrolyzable silyl group represented by the following general formula (1), wherein (B) as component (meth) acrylic acid ester polymer, a carboxyl group containing (meth) viewed contains one acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or any, and said (C) a tackifier resin as component, fully hydrogenated terpene Preparing a pressure-sensitive adhesive composition is a phenol resin
(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)
(2) Laminating the pressure-sensitive adhesive composition on both sides or one side of the substrate to form a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a non-cured pressure-sensitive adhesive composition (3) The pressure-sensitive adhesive composition heated, and an adhesive sheet having an adhesive layer comprising the cured adhesive composition, the silicon element concentration of the surface of the pressure-sensitive adhesive layer of the adhesive sheet according to elemental analysis of XPS and Z _1, the pressure-sensitive adhesive The silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the (meth) acrylic acid ester polymer as the component (B) from the composition The step of setting the silicon concentration change rate Z represented by the following general formula (A) to a value of 83% or less when Z ₀ is set.
A method for producing a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a pressure-sensitive adhesive composition without including a base material, and having release sheets on both sides of the pressure-sensitive adhesive layer, comprising the following steps (1) to (3): The manufacturing method of the adhesive sheet characterized by the above-mentioned.
(1) A pressure-sensitive adhesive composition comprising at least a terminal silyl group polymer as the component (A), a (meth) acrylic acid ester polymer as the component (B), and a tackifying resin as the component (C). The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain and has a urethane bond and / or a urea bond in a part of the main chain or a side chain. and, further, to both ends of the main chain, it has a hydrolyzable silyl group represented by the following general formula (1), wherein (B) as component (meth) acrylic acid ester polymer, a carboxyl group containing (meth) viewed contains one acrylic acid ester copolymer and non-functional (meth) acrylic acid ester polymer or any, and said (C) a tackifier resin as component, fully hydrogenated terpene Preparing a pressure-sensitive adhesive composition is a phenol resin
(In the general formula (1), X ¹ and X ² are independent and are a hydroxy group or an alkoxy group, and R is an alkyl group having 1 to 20 carbon atoms.)
(2) Step of laminating the pressure-sensitive adhesive composition on the surface of the release sheet to form a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a non-cured pressure-sensitive adhesive composition (3) Heating the pressure-sensitive adhesive composition Te, and an adhesive sheet having an adhesive layer comprising the cured adhesive composition, the silicon element concentration of the surface of the pressure-sensitive adhesive layer of the adhesive sheet according to elemental analysis of XPS and Z _1, the pressure-sensitive adhesive composition The silicon element concentration on the surface of the pressure-sensitive adhesive layer by XPS elemental analysis measurement of the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive composition prepared by removing the (meth) acrylate polymer as the component (B) from Z ₀ The silicon concentration change rate Z represented by the following general formula (A) is 83% or less.