JP5901044B2 - Double-sided pressure-sensitive adhesive sheet and method for producing double-sided pressure-sensitive adhesive sheet - Google Patents

Description

  The present invention relates to a double-sided PSA sheet and a method for producing a double-sided PSA sheet. In particular, the present invention relates to a double-sided pressure-sensitive adhesive sheet that can provide good constant load peeling characteristics even when the pressure-sensitive adhesive layer has a relatively high cohesive force, and a method for producing such a double-sided pressure-sensitive adhesive sheet.

Conventionally, pressure-sensitive adhesive sheets have been used in many fields such as general-purpose information display labels to electronic materials because of the advantage that they can be easily attached to an adherend by pressing. In addition, double-sided pressure-sensitive adhesive tapes having a pressure-sensitive adhesive layer on both surfaces of a base material are used in home appliances, automobiles, office automation equipment, and the like because they exhibit good workability and high reliability.
Here, in such a double-sided pressure-sensitive adhesive tape, in addition to the adhesive force required for a normal pressure-sensitive adhesive sheet, it begins to peel when a so-called low load in which a small stress is applied to the tape fixing surface for a long time is applied. Therefore, it is required to have a characteristic that the film is hardly peeled at an accelerated rate or is not displaced, that is, a good constant load peeling characteristic.

Thus, for example, a double-sided pressure-sensitive adhesive tape having a predetermined constant load peeling property has been proposed in order to improve resilience resistance (for example, Patent Document 1).
That is, Patent Document 1 discloses a double-sided adhesive tape used for fixing a liquid crystal display panel sandwiched between flexible printed circuit boards and a backlight housing, and has a loss tangent (Tanδ) at a frequency of 1 Hz. A double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer having a maximum value in a temperature range of −40 to −22 ° C. and a gel fraction of 15 to 45% is disclosed.

On the other hand, a pressure-sensitive adhesive sheet having an excellent adhesive force is proposed, which is not specifically aimed at improving the constant load peeling characteristics, but is characterized by using a pressure-sensitive adhesive composition containing a predetermined terminal silyl group polymer as a main ingredient. (For example, Patent Document 2).
That is, Patent Document 2 discloses that 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 represented by the following general formula (A) at the terminal. And 10 to 150 parts by mass of a tackifying resin, 0.001 to 10 mass of a fluorine-based compound selected from the group consisting of boron trifluoride and / or its complex, a fluorinating agent and an alkali metal salt of a fluorine-based inorganic acid The pressure-sensitive adhesive precursor is made into a pressure-sensitive adhesive layer by applying the pressure-sensitive adhesive precursor uniformly mixed to the surface of the tape base material or the sheet base material and then curing the terminal silyl group polymer. A pressure-sensitive adhesive sheet is disclosed.

(In general formula (A), X represents a hydroxy group or an alkoxy group, R represents an alkyl group having 1 to 20 carbon atoms, and n represents 0, 1 or 2.)

Japanese Patent No. 4645074 (Claims) WO2010 / 038715 (Claims)

  However, although the double-sided pressure-sensitive adhesive tape described in Patent Document 1 has a certain amount of constant load peeling characteristics, the gel fraction of the pressure-sensitive adhesive layer is relatively low, so when the double-sided pressure-sensitive adhesive tape is made into a roll form, There was a problem that the adhesive oozed out from the side surface over time.

  On the other hand, although the pressure-sensitive adhesive sheet described in Patent Document 2 shows high adhesive strength, an appropriate tackifying resin is not selected, and furthermore, loss tangent is not taken into consideration. There was a problem that it was difficult to obtain the required constant load peel characteristics.

Accordingly, the present inventors made extensive efforts in view of the above circumstances, and added a predetermined tackifying resin to a predetermined terminal silyl group polymer at a predetermined blending ratio, and a maximum value of loss tangent. The present invention has been found by improving the balance between adhesive force and cohesive force in the pressure-sensitive adhesive composition by obtaining a value within a predetermined range and obtaining good constant load peeling characteristics. It is.
That is, an object of the present invention is to provide a double-sided pressure-sensitive adhesive sheet that can obtain good constant load peeling characteristics even when the pressure-sensitive adhesive layer has a relatively high cohesive force, and the production of such a double-sided pressure-sensitive adhesive sheet. It is to provide a method.

  According to the present invention, there is provided a double-sided pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer made of a cured product of a pressure-sensitive adhesive composition on both surfaces of a substrate, wherein the pressure-sensitive adhesive composition of at least one pressure-sensitive adhesive layer is at least (A ) Terminal silyl group polymer as component and (B) component tackifying resin, and the terminal silyl group polymer as component (A) has a polyoxyalkylene structure in the main chain, It has a urethane bond and / or a urea bond in a part or side chain of the main chain, and further has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain. In addition, the tackifier resin of the component (B) contains a completely hydrogenated terpene phenol resin, and the blending amount of the tackifier resin is 100 parts by weight of the terminal silyl group polymer that is the component (A). 70-140 parts by weight The maximum value of loss tangent (tan δ) obtained by dynamic viscoelasticity measurement (frequency: 1 Hz) of the adhesive layer is set to a value within a range of −10 to 15 ° C. A double-sided PSA sheet is provided and can solve the above-mentioned problems.

(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 double-sided PSA sheet of the present invention, the PSA composition constituting the PSA layer contains a predetermined terminal silyl group polymer as the main agent and a predetermined tackifier resin as the tackifier resin. Due to this interaction, an excellent adhesive force can be exhibited.
Moreover, if it is the double-sided adhesive sheet of this invention, the adhesive layer of an adhesive composition can have the outstanding constant load peeling characteristic because it has the maximum value of a predetermined loss tangent.
Therefore, the double-sided pressure-sensitive adhesive sheet sufficiently exhibits the characteristics that do not easily cause displacement or peeling of these members, etc., even when a peeling stress is applied for a long time to the members, parts, etc., which are stuck and fixed. Therefore, excellent adhesion reliability can be obtained.
Moreover, since the terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, it is possible to impart appropriate flexibility to the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer to be obtained. .
Moreover, since it has the hydrolyzable silyl group represented by General formula (1) in the both ends of a principal chain, the crosslinking density of (A) components is adjusted to the suitable range, and in the adhesive composition after hardening Adjustment of the balance between adhesive force and cohesive force can be made easier.

  Another aspect of the present invention is a double-sided pressure-sensitive adhesive sheet that does not include a substrate and includes a pressure-sensitive adhesive layer made of a cured product of the pressure-sensitive adhesive composition, and the pressure-sensitive adhesive composition is at least as the component (A). Terminal silyl group polymer and (B) component tackifying resin, and the (A) component terminal silyl group polymer has a polyoxyalkylene structure in the main chain, It has a urethane bond and / or a urea bond in part or in the side chain, and further has hydrolyzable silyl groups represented by the following general formula (1) at both ends of the main chain. B) The tackifier resin of the component contains a fully hydrogenated terpene phenol resin, and the blending amount of the tackifier resin is 70 to 140 with respect to 100 parts by weight of the terminal silyl group polymer as the component (A). A value within the range of parts by weight And it is a double-sided adhesive sheet characterized by making the maximum value of loss tangent (tan-delta) obtained by the dynamic viscoelasticity measurement (frequency: 1 Hz) of an adhesive layer into the value in the range of -10-15 degreeC. .

(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, when the double-sided pressure-sensitive adhesive sheet does not contain a substrate, even if the adherend has irregularities, it can be flexibly followed and fixed to the irregularities.
Moreover, a cover sheet etc. can be further affixed on the surface after sticking.
Therefore, the double-sided pressure-sensitive adhesive sheet that does not include the base material of the present invention can impart excellent enforceability because it is easy to follow the uneven portion and stick it.

Moreover, in composing the double-sided pressure-sensitive adhesive sheet of the present invention, the blending amount of the completely hydrogenated terpene phenol-based tackifier resin is 30 to the total amount (100% by weight) of the tackifier resin as the component (B). A value within the range of 100% by weight is preferred.
By comprising in this way, the maximum value of the loss tangent of the adhesive composition which comprises the obtained adhesive layer can be adjusted, and the outstanding constant load peeling characteristic can be obtained.

Further, in constituting the double-sided pressure-sensitive adhesive sheet of the present invention, the pressure-sensitive adhesive composition contains, as the component (C), a catalyst for accelerating the curing of the terminal silyl group polymer as the component (A). Preferably, the catalyst is at least one selected from the group consisting of an aluminum catalyst, a titanium catalyst, a zirconium catalyst, a bismuth catalyst, and a boron trifluoride catalyst.
By comprising in this way, control of the crosslinking density of (A) component becomes easy, and adjustment of the balance of the adhesive force and cohesion force in the adhesive composition after hardening can be made still easier. .

Moreover, when comprising the double-sided adhesive sheet of this invention, it is preferable that an adhesive composition contains the silane coupling agent which has an amino group in a molecule | numerator as (D) component.
By comprising in this way, hardening of an adhesive composition can be accelerated | stimulated effectively.

Further, in constituting the double-sided pressure-sensitive adhesive sheet of the present invention, the gel fraction of the pressure-sensitive adhesive layer measured by an immersion method (solvent: ethyl acetate, temperature: 23 ° C., time: 120 hours) is in the range of 30 to 70%. It is preferable to set the value within the range.
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 peeling characteristics can be obtained.

Still another embodiment of the present invention is a method for producing a double-sided pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a cured product of a pressure-sensitive adhesive composition on both surfaces of a substrate, and the following steps (1) to (3) It is a manufacturing method of the double-sided adhesive sheet characterized by including.
(1) It contains at least a terminal silyl group polymer as the component (A) and a tackifier resin as the component (B), and the terminal silyl group polymer as the component (A) has a polyoxy group in the main chain. It has an alkylene structure, has a urethane bond and / or a urea bond in part of the main chain or in the side chain, and further has hydrolyzability represented by the following general formula (1) at both ends of the main chain. The terminal silyl group polymer 100 which has a silyl group, the (B) component tackifying resin contains a fully hydrogenated terpene phenol resin, and the blending amount of the tackifying resin is the (A) component. A step of preparing a pressure-sensitive adhesive composition having a value within the range of 70 to 140 parts by weight with respect to parts by weight (2) A step of laminating the pressure-sensitive adhesive composition on at least one surface of the substrate (3) pressure-sensitive adhesive Curing agent composition Both dynamic viscoelasticity measurement of the pressure-sensitive adhesive layer (Frequency: 1 Hz) step to a value within the range of the maximum value -10～15 ° C. loss obtained by tangent (tan [delta)

(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.)

By implementing in this way, the double-sided adhesive sheet which has the outstanding adhesive force and the constant load peeling characteristic can be manufactured efficiently.
More specifically, by producing the double-sided PSA sheet in this way, the maximum value of the loss tangent of the PSA layer can be set to a value within a predetermined range.
Therefore, it is possible to stably obtain a double-sided pressure-sensitive adhesive sheet having excellent adhesive strength and constant load peeling characteristics.

Moreover, another aspect of this invention is a manufacturing method of the double-sided adhesive sheet which does not contain a base material but was equipped with the adhesive layer which consists of hardened | cured material of an adhesive composition, Comprising: The following process (1)-(3 ), And a method for producing a double-sided pressure-sensitive adhesive sheet.
(1) It contains at least a terminal silyl group polymer as the component (A) and a tackifier resin as the component (B), and the terminal silyl group polymer as the component (A) has a polyoxy group in the main chain. It has an alkylene structure, has a urethane bond and / or a urea bond in part of the main chain or in the side chain, and further has hydrolyzability represented by the following general formula (1) at both ends of the main chain. The terminal silyl group polymer 100 which has a silyl group, the (B) component tackifying resin contains a fully hydrogenated terpene phenol resin, and the blending amount of the tackifying resin is the (A) component. Step of preparing a pressure-sensitive adhesive composition having a value within the range of 70 to 140 parts by weight relative to parts by weight (2) Step of laminating the pressure-sensitive adhesive composition on the surface of the release substrate (3) Pressure-sensitive adhesive composition The product is cured and the adhesive layer As well as, a dynamic viscoelasticity measurement of the obtained adhesive layer (Frequency: 1 Hz) step of the loss tangent obtained by a maximum of (tan [delta) to a value within the range of -10～15 ° C.

(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.)

By implementing in this way, the double-sided adhesive sheet which does not contain the base material which has the outstanding adhesive force and the constant load peeling characteristic can be manufactured efficiently.
More specifically, even when there is no substrate, by laminating the pressure-sensitive adhesive composition on the surface of the release substrate, a double-sided pressure-sensitive adhesive sheet having excellent adhesive force and constant load release characteristics can be efficiently obtained. Can be manufactured.
Therefore, by manufacturing the double-sided pressure-sensitive adhesive sheet in this way, the maximum value of the loss tangent of the pressure-sensitive adhesive layer can be set to a value within a predetermined range.
That is, it is possible to stably obtain a double-sided pressure-sensitive adhesive sheet that does not include a base material and has an excellent balance between the adhesive strength and the constant load peeling property.

1 (a) to 1 (b) are diagrams for explaining a predetermined terminal silyl group polymer. 2 (a) to 2 (b) are diagrams provided for explaining an FT-IR spectrum of a predetermined tackifier resin. FIG. 3 is a diagram provided to explain the relationship between the blending amount of a predetermined tackifying resin and the maximum value of the loss tangent. FIG. 4 is a diagram provided for explaining the relationship between the blending amount of a predetermined tackifying resin and the adhesive strength. FIG. 5 is a diagram provided to explain the relationship between the blending amount of a predetermined tackifying resin and the constant load peeling characteristics. 6 (a) to 6 (c) are diagrams provided to explain each aspect of the double-sided pressure-sensitive adhesive sheet. 7 (a) to 7 (d) are other views provided for explaining a method for producing a double-sided pressure-sensitive adhesive sheet, respectively.

[First Embodiment]
An embodiment of the present invention is a double-sided pressure-sensitive adhesive sheet provided with a pressure-sensitive adhesive layer made of a cured product of a pressure-sensitive adhesive composition on both surfaces of a substrate, and the pressure-sensitive adhesive composition of at least one pressure-sensitive adhesive layer is at least ( A) terminal silyl group polymer as component and (B) component tackifying resin are included, and the terminal silyl group polymer as component (A) has a polyoxyalkylene structure in the main chain. , Having a urethane bond and / or a urea bond in part of the main chain or in the side chain, and further having a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain The tackifier resin of component (B) contains a completely hydrogenated terpene phenol resin, and the blending amount of the tackifier resin is 100 parts by weight of the terminal silyl group polymer as component (A). 70-140 weight The maximum value of loss tangent (tan δ) obtained by dynamic viscoelasticity measurement (frequency: 1 Hz) of the pressure-sensitive adhesive layer is set to a value within the range of −10 to 15 ° C. It is a double-sided pressure-sensitive adhesive sheet.
Hereinafter, a first embodiment of the present invention will be specifically described with reference to the drawings as appropriate.

(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.)

1. Pressure-sensitive adhesive layer The double-sided pressure-sensitive adhesive sheet of the present invention comprises a predetermined pressure-sensitive adhesive composition containing a predetermined terminal silyl group polymer as the component (A) and a predetermined tackifying resin as the component (B). And
Hereinafter, this adhesive composition is demonstrated for every component.

(1) Component (A): Terminal silyl group polymer (1) -1 type The terminal silyl group polymer as the component (A) has a urethane bond and a urea bond in the main chain or side chain, or one of them, It has the hydrolyzable silyl group represented by the general formula (1) described above at both ends of the main chain.

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, the combination with predetermined tackifying resin can exhibit the outstanding adhesive force, and can express high reliability as a double-sided 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. This is because an excellent cohesive force can be exhibited by adjusting to.
Therefore, the pressure-sensitive adhesive composition itself can prevent the pressure-sensitive adhesive from oozing out from the side surface over time when the roll composition is formed.
Therefore, by using a predetermined terminal silyl group polymer as the component (A), it is possible to obtain a pressure-sensitive adhesive composition having an excellent balance between adhesive force and cohesive force and high adhesion reliability.
In general formula (1), the number of carbon atoms of the alkyl group represented by R is more preferably 1 to 12 and even more preferably 1 to 3 from the viewpoint of hydrolytic dehydration condensation reactivity.
Moreover, when X < ¹ > or X < ² > is an alkoxy group in General formula (1), it is preferable that the carbon number in the said alkoxy group is 1-12 from a hydrolytic dehydration condensation reactivity viewpoint, 3 is more preferable.

(I) Basic Configuration Next, the basic configuration of the predetermined terminal silyl group polymer as the component (A) will be described.
That is, the terminal silyl group polymer is composed of a predetermined end portion and a predetermined skeleton portion.
A specific method for synthesizing the terminal silyl group polymer will be described in the third embodiment.

(Ii) Terminal part First, the specific structure of the terminal part 32 (32a, 32b) of the predetermined terminal silyl group polymer 30 shown in FIG. 1 (a) is represented by the following general formulas (2) to (8) (terminal part- A to G).

(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 General Formula (8), X ³ is an alkylene group, and X ⁴ represents an organic group having 1 to 20 carbon atoms.)

  That is, when the terminal silyl group polymer has such a terminal portion, the adhesion to the adherend can be further strengthened.

(Iii) Skeletal portion The skeleton of the main chain 12 or the side chain (not shown) of the predetermined terminal silyl group polymer shown in FIG. 1 (a) is polyoxyalkylene.
The reason for this is that if it is polyoxyalkylene, it is possible to impart moderate flexibility to the resulting pressure-sensitive adhesive composition and to further improve the adhesion to the adherend.
Specific examples of such polyoxyalkylene include polyoxypropylene and polyoxyethylene.

(Iv) Position of hydrolyzable silyl group The predetermined terminal silyl group polymer as component (A) is hydrolyzable represented by the general formula (1) in the side chain as shown in FIG. It is characterized by being a both-end silyl group polymer having no hydrolyzable silyl group represented by the general formula (1) only at both ends of the main chain, having no silyl group.
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.

Further, 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, It is preferable to set the value within the range of 0.1 to 30 parts by weight with respect to 100 parts by weight of the polymer.
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, if the blending amount of the one-terminal silyl group polymer is less than 0.1 part by weight, the effect of addition may not be sufficiently obtained. On the other hand, when the blending amount of the one-terminal silyl group polymer exceeds 30 parts by weight, the crosslinking density between the components (A) may be excessively decreased, and it may be difficult to obtain a predetermined gel fraction. Because there is.
Therefore, the blending amount of the one-terminal silyl group polymer is more preferably set to a value within the range of 0.5 to 10 parts by weight with respect to 100 parts by weight of both terminal silyl group polymers, and the range of 1 to 5 parts by weight. More preferably, the value is 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.

(1) -2 Weight average molecular weight Moreover, it is preferable to make the weight average molecular weight of the predetermined | prescribed terminal silyl group polymer which is (A) component into the value within the range of 1000-200,000.
The reason for this is that when the weight average molecular weight is less than 1000, the molecular structure becomes dense and sufficient adhesive strength cannot be obtained, and the viscosity becomes too low, resulting in poor workability when forming a sheet by solution coating. Because there is. On the other hand, when the weight average molecular weight exceeds 200,000, the processability due to increase in viscosity or the like is significantly decreased, or the crosslinking density is excessively decreased to adjust the balance between adhesive force and cohesive force. This may be difficult.
Therefore, the weight average molecular weight of the predetermined terminal silyl group polymer as the component (A) is more preferably set to a value within the range of 1000 to 150,000, and further preferably set to a value within the range of 10,000 to 100,000. preferable.
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.

(1) -3 Blending amount The blending amount of the predetermined terminal silyl group polymer as the component (A) is in the range of 20 to 90 wt% with respect to 100 wt% of the total amount of the pressure-sensitive adhesive composition before curing. It is preferable to set the value within the range.
The reason for this is that when the blending amount is less than 20% by weight, the absolute amount of the component (A) with respect to the entire pressure-sensitive adhesive composition becomes excessively small, and it may be difficult to obtain sufficient cohesive force. Because there is. On the other hand, when the blending amount exceeds 90% by weight, the absolute amount of the component (A) with respect to the entire pressure-sensitive adhesive composition is excessively increased, and it may be difficult to obtain sufficient adhesive strength. Because.
Therefore, the blending amount of the predetermined terminal silyl group polymer as the component (A) is set to a value within the range of 25 to 85% by weight with respect to 100% by weight of the total amount of the pressure-sensitive adhesive composition before curing. More preferably, the value is more preferably in the range of 30 to 80% by weight.

(2) Component (B): Tackifying resin (2) -1 Completely hydrogenated terpene phenolic resin In constituting the adhesive composition of the double-sided PSA sheet, the tackifying resin as component (B) is a fully hydrogenated terpene. It contains a phenolic resin.
This is because the pressure-sensitive adhesive composition of the double-sided pressure-sensitive adhesive sheet contains a completely hydrogenated terpene phenol-based resin, so that it becomes easy to adjust the glass transition point of the pressure-sensitive adhesive layer as described later. This is because even if the cohesive force is a relatively high value, a predetermined constant load peeling characteristic can be obtained.
Here, the completely hydrogenated terpene phenol resin is a resin obtained by hydrogenating a terpene phenol resin.
More specifically, the terpene phenol resin has a terpene-derived double bond and an aromatic ring double bond derived from phenols.
Therefore, in the present invention, the completely hydrogenated terpene phenol resin means a resin in which both the terpene moiety and the phenol moiety are completely or almost hydrogenated.
In addition, whether it corresponds to a fully hydrogenated terpene phenol-type resin can be judged using the FT-IR spectrum obtained by a Fourier transform infrared spectrophotometer (FT-IR) so that it may mention later.

Then, 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) -2 Other tackifying resin It is preferable that other tackifying resin is further included as a part of (B) component. Here, the kind of tackifier is not particularly limited, rosin resin such as polymerized rosin, polymerized rosin ester, rosin derivative, polyterpene resin, aromatic modified terpene resin and its hydride, terpene phenol resin, coumarone Indene resin, aliphatic petroleum resin, aromatic petroleum resin and its hydride, aliphatic / aromatic copolymer petroleum resin, partially hydrogenated terpene phenol resin, low molecular mass coalescence of styrene or substituted styrene, etc. At least one type is exemplified.
The reason for this is that if these tackifying resins, without inhibiting the interaction between the above-mentioned fully hydrogenated terpene phenol and the predetermined terminal silyl group polymer (A), for the adhesive composition, This is because excellent adhesive strength can be imparted.

(2) -3 Softening point Moreover, it is preferable to make the softening point of tackifying resin which is (B) component into the value within the range of 70-160 degreeC.
The reason for this is that when the softening point of the tackifying resin as the component (B) is a value of less than 70 ° C., the adhesiveness and adhesiveness of the adhesive layer to the substrate may be lowered. On the other hand, when the softening point exceeds 160 ° C., compatibility with other pressure-sensitive adhesive components may decrease.
Therefore, it is more preferable that the softening point of the tackifying resin as the component (B) is in the range of 90 to 150 ° C.
In the present invention, the softening point is a value measured in accordance with JIS K2531.

(2) -4 Weight average molecular weight Moreover, it is preferable to make the weight average molecular weight of tackifying resin which is (B) component into the value within the range of 300-5000.
The reason for this is that when the weight average molecular weight of the tackifying resin as component (B) is less than 300, the cohesive force is excessively reduced, and the adhesive oozes out over time when it is made into a roll form. This is because there are cases. On the other hand, when the weight average molecular weight exceeds 5000, the adhesive strength may be excessively reduced.
Therefore, it is more preferable that the weight average molecular weight of the tackifying resin as the component (B) is set to a value within the range of 500 to 3000.

(2) -5 Blending amount Moreover, the blending amount of the tackifier resin as the component (B) is within the range of 70 to 140 parts by weight with respect to 100 parts by weight of the predetermined terminal silyl group polymer as the component (A). It is set as the value of.
The reason for this is that a pressure-sensitive adhesive composition having an excellent balance between adhesive force and cohesive force can be obtained by setting the blending amount of the component (B) within the range.
That is, when the blending amount is less than 70 parts by weight, the absolute amount of the component (B) with respect to the entire pressure-sensitive adhesive composition becomes excessively small, and it may be difficult to obtain sufficient adhesive strength. It is. On the other hand, when the blending amount exceeds 140 parts by weight, the absolute amount of the component (B) with respect to the entire pressure-sensitive adhesive composition is excessively increased, the cohesive force is excessively decreased, and when the roll is formed, This is because the adhesive may ooze out over time.
Therefore, the blending amount of the predetermined tackifying resin as the component (B) is set to a value within the range of 75 to 130 parts by weight with respect to 100 parts by weight of the terminal silyl group polymer as the component (A). Preferably, the value is in the range of 85 to 120 parts by weight.

Further, the blending amount of the fully hydrogenated terpene phenol tackifying resin may be set to a value within the range of 30 to 100% by weight with respect to the total amount (100% by weight) of the tackifying resin as the component (B). preferable.
The reason for this is that even if the cohesive strength of the pressure-sensitive adhesive composition is set to a relatively high value by setting the blending amount of the fully hydrogenated terpene phenol-based tackifying resin to a value within such a range, an excellent determination is obtained. This is because load peeling characteristics can be imparted.
That is, when the blending amount is less than 30% by weight, it is difficult to adjust the glass transition point of the terminal silyl group polymer, and it may be difficult to obtain sufficient constant load peeling characteristics. .
Therefore, the blending amount of the fully hydrogenated terpene phenol tackifying resin is set to a value within the range of 50 to 100% by weight with respect to the total amount (100% by weight) of the tackifying resin as the component (B). Is more preferable, and a value within the range of 70 to 100% by weight is even more preferable.

Here, the relationship between the compounding quantity of predetermined tackifying resin and the maximum value of loss tangent is demonstrated using FIG.
That is, in FIG. 3, the dynamic viscoelasticity in the double-sided pressure-sensitive adhesive sheet having the horizontal axis representing the amount (parts by weight) of the predetermined tackifying resin and the vertical axis representing the obtained pressure-sensitive adhesive composition as the pressure-sensitive adhesive layer. Characteristic curves A and B taking the maximum value of loss tangent (Tanδ) obtained by measurement (frequency: 1 Hz) are shown.
The characteristic curve A is a characteristic curve when a completely hydrogenated terpene phenol tackifying resin is used, and the characteristic curve B is a characteristic curve when a non-hydrogenated terpene phenol tackifying resin is used.
Further, when looking at the characteristic curve A using the completely hydrogenated terpene phenol resin, the Tanδ of the pressure-sensitive adhesive layer is relatively high compared to the characteristic curve B using the non-hydrogenated terpene phenol resin. I understand that.
Then, since Tan δ is a value corresponding to the glass transition point of the pressure-sensitive adhesive layer, the pressure-sensitive adhesive when using a completely hydrogenated terpene phenol-based resin is greater than when using a non-hydrogenated terpene-phenol resin. It is understood that it is easy to set the glass transition point of the layer high.
In addition, the specific composition of an adhesive composition and the measuring method of Tan (delta) are described in an Example.

Next, the relationship between the blending amount of the predetermined pressure-sensitive adhesive-imparting resin and the adhesive strength will be described with reference to FIG.
That is, in FIG. 4, the horizontal axis represents the amount (parts by weight) of the predetermined tackifying resin, and the vertical axis represents the adhesive strength of the double-sided pressure-sensitive adhesive sheet having the obtained pressure-sensitive adhesive composition as the pressure-sensitive adhesive layer. Characteristic curves C and D are shown.
The characteristic curve C is a characteristic curve when a completely hydrogenated terpene phenol tackifying resin is used, and the characteristic curve D is a characteristic curve when a non-hydrogenated terpene phenol tackifying resin is used.
Further, from the characteristic curve C and the characteristic curve D, the adhesive force is the same as the amount of the tackifying resin is increased both in the case of using the completely hydrogenated terpene phenol resin and in the case of using the non-hydrogenated terpene phenol resin. It shows an increasing trend, and it is understood that the difference is small.
In addition, the specific composition of an adhesive composition and the measuring method of adhesive force are described in an Example.

Next, the relationship between the blending amount of the predetermined pressure-sensitive adhesive resin and the constant load peeling characteristics will be described with reference to FIG.
That is, in FIG. 5, the constant load release property in the double-sided pressure-sensitive adhesive sheet having the horizontal axis representing the amount (parts by weight) of the predetermined tackifying resin and the vertical axis representing the obtained pressure-sensitive adhesive composition as the pressure-sensitive adhesive layer. A characteristic curve E is shown.
Moreover, the characteristic curve E is a characteristic curve when using a completely hydrogenated terpene phenol-based tackifying resin. When the blending amount is 0 part by weight, the test piece is removed during 24 hours from the start of measurement. Since it was completely peeled off from the SUS plate and dropped, it is not shown.
And, when looking at the characteristic curve E, the constant load peeling property is improved as the blending amount of the fully hydrogenated terpene phenolic resin increases. It is understood that the constant load peeling characteristic can be stably obtained.
On the other hand, when a non-hydrogenated terpene phenol resin is used, the test piece is completely peeled off from the SUS plate and dropped during 24 hours from the start of the measurement, and thus is not shown.

Then, from FIG. 3 to FIG. 5, when a predetermined amount of completely hydrogenated terpene phenol resin is included in the tackifier resin, Tan δ of the pressure-sensitive adhesive layer, that is, the glass transition point can be adjusted relatively high. It will be understood that it becomes easy, has good adhesive strength, and can improve the constant load release characteristics.
On the other hand, when only the non-hydrogenated terpene phenol resin is used, the adhesive strength can be sufficiently obtained, but it is not easy to adjust the glass transition point of the pressure-sensitive adhesive layer, and the constant load peeling property is inferior. It is understood.
Therefore, it is understood that it is important to include a predetermined amount of a fully hydrogenated terpene phenol-based resin in the tackifying resin in order to improve the constant load peeling characteristics required for the double-sided PSA sheet.
In addition, the specific composition of an adhesive composition and the measuring method of a constant load peeling characteristic are described in an Example.

(3) (C) component: catalyst (3) -1 type Moreover, in comprising the adhesive composition as an adhesive layer in the double-sided adhesive sheet of this invention, an adhesive composition is as (C) component, (A) The catalyst for accelerating hardening of the predetermined | prescribed terminal silyl group polymer which is a component is included, and the said catalyst is from the group which consists of an aluminum catalyst, a titanium catalyst, a zirconium catalyst, and a boron trifluoride catalyst. It is preferable that it is at least one selected.
The reason for this is that if these catalysts are used, the crosslink density between the components (A) can be easily controlled, and the balance between the adhesive force and the cohesive force in the adhesive composition after curing can be further facilitated. This is because it can.

  As the aluminum-based catalyst, aluminum alkoxide, aluminum chelate, and aluminum (III) chloride are preferable. As the titanium-based catalyst, titanium alkoxide, titanium chelate, and titanium (IV) chloride are preferable. As the zirconium-based catalyst, Zirconium alkoxides, zirconium chelates, and zirconium (IV) chloride are preferable. As the boron trifluoride-based catalyst, an amine complex or an alcohol complex of boron trifluoride is particularly preferably used.

(3) -2 Blending amount The blending amount of the catalyst as the component (C) is within the range of 0.001 to 10 parts by weight with respect to 100 parts by weight of the predetermined terminal silyl group polymer as the component (A). It is preferable to set the value of.
The reason for this is that when the amount is less than 0.001 part by weight, the catalytic action becomes insufficient and the cohesive force of the pressure-sensitive adhesive composition may be excessively reduced. On the other hand, when the blending amount exceeds 10 parts by weight, the catalytic action becomes excessive, and the pressure-sensitive adhesive composition may be cured before being applied to the substrate.
Therefore, the blending amount of the catalyst as the component (C) is more preferably set to a value within the range of 0.01 to 8 parts by weight with respect to 100 parts by weight of the predetermined terminal silyl group polymer as the component (A). Preferably, the value is in the range of 0.05 to 5 parts by weight.

(4) (D) component: Silane coupling agent Moreover, in comprising the adhesive composition as an adhesive layer in the double-sided adhesive sheet of this invention, an adhesive composition has an amino group as (D) component. It is preferable to contain 1 mol or more of the silane coupling agent having 1 mol of component (C).
The reason for this is that by blending a silane coupling agent having an amino group in such a range, the effect of the predetermined terminal silyl group polymer as a crosslinking aid is exhibited, and the cohesive force of the pressure-sensitive adhesive composition is more suitable. This is because the range can be adjusted.
Therefore, it is more preferable to set the blending amount of the silane coupling agent having an amino group as the component (D) to a value within the range of 1 to 30 mol with respect to 1 mol of the component (C). It is more preferable to set the value within the range.
Examples of the silane coupling agent having an amino group include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (Aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and the like are preferably used.

(5) Additive In addition, the pressure-sensitive adhesive composition as the pressure-sensitive adhesive layer in the double-sided pressure-sensitive adhesive sheet of the present invention includes, for example, an anti-aging agent, a dehydrating agent such as a vinylsilane compound or calcium oxide, and a filling agent. Agent, conductive material, heat conductive material, plasticizer, anhydrous silica, thixotropic agent such as amide wax, diluent such as isoparaffin, aluminum hydroxide, halogen flame retardant, phosphorus flame retardant, silicone flame retardant, etc. These flame retardants, functional oligomers such as silicone alkoxy oligomers and acrylic oligomers, pigments, titanate coupling agents, aluminum coupling agents, and drying oils may be added and mixed.
In addition, when these additives are added, although depending on the type of the additive, it is preferable to add the additives so as not to impair the effects of the present invention. The value is preferably in the range of 0.01 to 100 parts by weight, more preferably in the range of 0.01 to 70 parts by weight, with respect to 100 parts by weight of the silyl group polymer. A value in the range of ˜40 parts by weight is particularly preferable.

(6) Gel fraction Moreover, in comprising the adhesive composition as an adhesive layer in the double-sided adhesive sheet of this invention, the gel fraction of an adhesive layer shall be made into the value within the range of 30-70%. preferable.
The reason for this is that by setting the gel fraction of the pressure-sensitive adhesive layer to a value within this range, excellent cohesive force can be exerted. It is because it can suppress coming.
That is, when the gel fraction of the pressure-sensitive adhesive layer is less than 30%, the cohesive force becomes excessively small, and the pressure-sensitive adhesive layer may ooze out from the side surface over time when the roll is formed. It is.
On the other hand, if the gel fraction of the pressure-sensitive adhesive layer becomes excessively high, sufficient adhesive strength may not be obtained.
Accordingly, the gel fraction of the pressure-sensitive adhesive layer in the pressure-sensitive adhesive composition is more preferably set to a value within the range of 35 to 65%, and further preferably set to a value within the range of 40 to 60%.
The “gel fraction of the pressure-sensitive adhesive layer” means that after the pressure-sensitive adhesive composition is applied to the base material or the release material, seasoning is performed for 14 days in a 23 ° C., 50% RH environment, and then after the seasoning. This means the gel fraction measured by the dipping method using the pressure-sensitive adhesive composition (pressure-sensitive adhesive layer) as a measurement sample.
Moreover, about the specific measuring method of a gel fraction, it describes in an Example.

(7) Thickness Further, the thickness of the pressure-sensitive adhesive layer is preferably set to a value within the range of 1 to 100 μm, and more preferably set to a value within the range of 5 to 50 μm.
This is because if the thickness of the pressure-sensitive adhesive layer is too thin, sufficient adhesive properties and the like may not be obtained, and conversely, if it is too thick, the residual solvent may cause a problem.

(8) Aspect In the present invention, as shown in FIG. 6B, when the adhesive layer 40 made of a cured product of the predetermined adhesive composition described above is laminated only on one side of the substrate, The pressure-sensitive adhesive layer 50 laminated on the other surface of the material is not particularly limited, but is preferably an acrylic pressure-sensitive adhesive, a polyester pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, or the like.

2. Substrate Moreover, it is preferable that the double-sided pressure-sensitive adhesive sheet of the present invention has pressure-sensitive adhesive layers 40 and 40 ′ on one side or both sides of the base material 2 as shown in FIGS.
Examples of such a substrate include polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyimide, polyetherimide, polyetherketone, polyetheretherketone, polycarbonate, polymethylmethacrylate, triacetylcellulose, polynorbornene. A resin film made of a resin such as ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, vinyl chloride, polyurethane acrylate, polyether sulfone, polyphenyl ether sulfone is preferable. Can be mentioned.

  Further, the thickness of the substrate is not particularly limited, but is usually preferably a value in the range of 1 to 1,000 μm, more preferably a value in the range of 10 to 100 μm. .

3. Release substrate (release film)
Moreover, it is also preferable that the double-sided adhesive sheet of this invention is an aspect by which the peeling base material (peeling film) is bonded with respect to both surfaces of an adhesive layer.
Such an embodiment is required when only the pressure-sensitive adhesive layer has to be transported, for example, because the production of the pressure-sensitive adhesive layer and the use of the pressure-sensitive adhesive layer are performed in different places.
In addition, as such a release substrate, for example, a release agent such as a silicone resin is applied to a polyester film such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, or a polyolefin film such as polypropylene or polyethylene, and a release layer. Are provided.
Moreover, the thickness of this peeling base material can be normally taken as the value within the range of 20-150 micrometers.
In addition, by providing a predetermined difference in the peeling force from the pressure-sensitive adhesive layer in the two peeling substrates, the pressure-sensitive adhesive layer partially follows when the peeling substrate having the lower peeling force is peeled off. This can be prevented.

[Second Embodiment]
2nd Embodiment is a double-sided adhesive sheet which does not contain a base material but was equipped with the adhesive layer which consists of hardened | cured material of an adhesive composition, Comprising: An adhesive composition is terminal silyl as a (A) component at least. A base polymer and a tackifying resin as component (B), and the terminal silyl group polymer as component (A) has a polyoxyalkylene structure in the main chain, and a part of the main chain or It has a urethane bond and / or a urea bond in the side chain, and further has hydrolyzable silyl groups represented by the following general formula (1) at both ends of the main chain, and component (B) The tackifying resin contains a completely hydrogenated terpene phenol-based resin, and the blending amount of the tackifying resin is 70 to 140 parts by weight with respect to 100 parts by weight of the terminal silyl group polymer as the component (A). The value is within the range, and the viscosity is Dynamic viscoelasticity measurement (frequency: 1 Hz) of the adhesive layer is a double-sided pressure-sensitive adhesive sheet, wherein a loss tangent obtained by a maximum of (tan [delta) to a value within the range of -10~15 ℃.

(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, by comprising in this way, even if a to-be-adhered body has an unevenness | corrugation, it can follow the uneven | corrugated | grooved part flexibly and can be fixed.
Moreover, a cover sheet etc. can be further affixed on the surface after sticking.
Moreover, as for the double-sided adhesive sheet which does not contain the base material of this invention, it is a preferable aspect to laminate | stack the adhesive layer 40 on the surface of the peeling base material 8, as shown in FIG.6 (c).
Moreover, it is good also as an aspect by which the above-mentioned adhesive layer was clamped with two peeling base materials.
In addition, since it is the same as that of the structure of the double-sided adhesive sheet containing the base material which is 1st Embodiment except a base material, specific description is abbreviate | omitted.

[Third Embodiment]
3rd Embodiment is a manufacturing method of the double-sided adhesive sheet provided with the adhesive layer which consists of hardened | cured material of an adhesive composition on both surfaces of a base material, Comprising: The following process (1)-(3) is included. Is a method for producing a double-sided PSA sheet.
(1) It contains at least a terminal silyl group polymer as the component (A) and a tackifier resin as the component (B), and the terminal silyl group polymer as the component (A) has a polyoxy group in the main chain. Hydrolyzable silyl having an alkylene structure, having a urethane bond and / or a urea bond in one part or a side chain of the main chain, and further having both ends of the main chain represented by the general formula (1) The component (B) tackifying resin contains a fully hydrogenated terpene phenol resin, and the blending amount of the tackifying resin is changed to 100 weights of the terminal silyl group polymer as the component (A). Step of preparing a pressure-sensitive adhesive composition having a value within the range of 70 to 140 parts by weight with respect to part (2) Step of laminating the pressure-sensitive adhesive composition on at least one surface of the substrate (3) Pressure-sensitive adhesive When the composition is cured The step of setting the maximum value of the loss tangent (tan δ) obtained by dynamic viscoelasticity measurement (frequency: 1 Hz) of the pressure-sensitive adhesive layer to a value within the range of −10 to 15 ° C. Hereinafter, described in the first embodiment The manufacturing method of the double-sided pressure-sensitive adhesive sheet will be specifically described with reference to the drawings with respect to the steps for manufacturing the pressure-sensitive adhesive sheet, focusing on the points different from the contents described above.

(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.)

(1) Step (1) (Preparation step of pressure-sensitive adhesive composition)
Step (1) is a step of preparing a predetermined pressure-sensitive adhesive composition containing the components (A) to (B).
Here, FIG. 1A shows a synthesis example of a predetermined terminal silyl group polymer 30 as the component (A).
First, a polymer skeleton 10 having an isocyanate group 14 (14a, 14b) at the end of the main chain 12 or side chain (not shown) of the molecule is prepared.
Next, a silyl having an active hydrogen group 22 capable of reacting with an isocyanate group 14 (14a, 14b) at one end of the molecule and a hydrolyzable silyl group 24 represented by the general formula (1) at another end of the molecule. An agent 20 is prepared.
Next, after the polymer skeleton 10 and the silylating agent 20 are mixed, the predetermined terminal silyl group polymer 30 can be obtained, for example, by reacting at 80 ° C. for 1 hour in a nitrogen atmosphere.
In addition, as shown in FIG. 1B, the predetermined terminal silyl group polymer 30 is cured by a crosslinking reaction via hydrolysis (30 ′) of the hydrolyzable silyl group represented by the general formula (1). In other words, it is a so-called moisture curable polymer having a three-dimensional network structure (30 ″).

When synthesizing the terminal silyl group polymer, the silylating agent 20 has the isocyanate group 14 and the polymer skeleton 10 has the active hydrogen group 22, contrary to the case of FIG. Also good.
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, it is preferable to dilute the obtained component (A) with a diluent solvent as desired, and add the component (B) with stirring to obtain a uniform mixed solution.
Subsequently, the component (C) and the component (D) or other additives are added to the obtained mixed solution, and then stirred as necessary until the desired viscosity is obtained. It is preferable to obtain a solution of the pressure-sensitive adhesive composition by further adding a dilution solvent.
In addition, since the detail of other components, the compounding quantity, etc. are as having already described, it abbreviate | omits.

(2) Step (2) (Applying step of pressure-sensitive adhesive composition)
Step (2) is a step of forming the coating layers 4 and 4 ′ by applying the pressure-sensitive adhesive composition to the substrate 2 as shown in FIG.
Moreover, as a method of apply | coating an adhesive composition on the base material 2, a solvent is added using the bar coat method, the knife coat method, the roll coat method, the blade coat method, the die coat method, the gravure coat method etc., for example. It is preferable to dry after applying the adhesive composition to form the coating layer 4 (coating film).
At this time, the thickness of the coating layer 4 is preferably set to a value within the range of 1 to 100 μm, and more preferably set to a value within the range of 5 to 50 μm.
This is because if the thickness of the coating layer 4 is too thin, sufficient adhesive properties and the like may not be obtained, and conversely, if it is too thick, the residual solvent may become a problem.
Moreover, as drying conditions, it is usually preferable to set it within a range of 10 to 10 minutes at 50 to 150 ° C.
The details of the base material are the same as described above, and will be omitted.

(3) Step (3) (Coating layer curing step)
Step (3) is a step in which the coating layers 4 and 4 ′ of the pressure-sensitive adhesive composition are cured to form the coating layers 4 and 4 ′ as pressure-sensitive adhesive layers 40 and 40 ′.
That is, as shown in FIGS. 7B to 7C, in a state where the release base materials 8 and 8 ′ are laminated on the surface of the coating layers 4 and 4 ′ that are dried on the base material 2. It is preferable to make it harden | cure and it is set as the adhesive layers 40 and 40 '.
Alternatively, the application layers 4 and 4 'of the pressure-sensitive adhesive composition applied on the substrate 2 are first cured to form the pressure-sensitive adhesive layers 40 and 40', and then laminated on the release substrates 8 and 8 '. May be.
Or it is not necessary to laminate | stack the peeling base material 8 to the last.

In addition, hardening in the application layer 4 of an adhesive composition is performed through the drying process mentioned above and a seasoning process.
Conditions for the seasoning step include a temperature of 20 to 50 from the viewpoint of uniformly curing the coating layer 4 of the pressure-sensitive adhesive composition without damaging the coating layer 4 and the base material 2 of the pressure-sensitive adhesive composition. It is preferable to set it as ° C, and it is more preferable to set it as 23-30 ° C.
The humidity is preferably 30 to 75% RH, and more preferably 45 to 65% RH.
In addition, as a method of bonding the finally obtained double-sided pressure-sensitive adhesive sheet 100 to the adherend 200, first, as shown in FIGS. 7C to 7D, the pressure-sensitive adhesive layer 40 is first laminated. It is preferable that the release film 8 is peeled, and then the surface of the pressure-sensitive adhesive layer 40 that appears is adhered to the adherend 200 by adhesion.

(4) Adherent The type of adherend to which the double-sided pressure-sensitive adhesive sheet of the present invention is applied is not particularly limited, but a resin such as a polycarbonate resin, a polymethyl methacrylate resin, a polystyrene resin, or an ABS resin. Etc. or glass is preferably used as the adherend.

[Fourth Embodiment]
4th Embodiment is a manufacturing method of the double-sided adhesive sheet which does not contain a base material but was equipped with the adhesive layer which consists of hardened | cured material of an adhesive composition, Comprising: The following process (1)-(3) is included. Is a method for producing a double-sided PSA sheet.
(1) It contains at least a terminal silyl group polymer as the component (A) and a tackifier resin as the component (B), and the terminal silyl group polymer as the component (A) has a polyoxy group in the main chain. It has an alkylene structure, has a urethane bond and / or a urea bond in part of the main chain or in the side chain, and further has hydrolyzability represented by the following general formula (1) at both ends of the main chain. The terminal silyl group polymer 100 which has a silyl group, the (B) component tackifying resin contains a fully hydrogenated terpene phenol resin, and the blending amount of the tackifying resin is the (A) component. Step of preparing a pressure-sensitive adhesive composition having a value within the range of 70 to 140 parts by weight relative to parts by weight (2) Step of laminating the pressure-sensitive adhesive composition on the surface of the release substrate (3) Pressure-sensitive adhesive composition The product is cured and the adhesive layer As well as, a dynamic viscoelasticity measurement of the obtained adhesive layer (Frequency: 1 Hz) step of the loss tangent obtained by a maximum of (tan [delta) to a value within the range of -10～15 ° C.

(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, by manufacturing in this way, a predetermined double-sided pressure-sensitive adhesive sheet can be efficiently manufactured even when the substrate is not included.
In addition, in a process (2), manufacture of the double-sided adhesive sheet containing the base material which is 3rd Embodiment except the process of apply | coating an adhesive composition to the surface of the peeling base material 8, and forming the application layer 4. FIG. Since it is the same as the method, a specific description is omitted.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1]
1. Preparation of pressure-sensitive adhesive composition (1) Preparation of silylating agent A reaction vessel was charged with 206 parts by weight of N-aminoethyl-γ-aminopropylmethyldimethoxysilane and 172 parts by weight of methyl acrylate at 80 ° C. in a nitrogen atmosphere. Was stirred for 10 hours to obtain a silane compound to be a silylating agent.

(2) Preparation of urethane prepolymer In another reaction vessel, polyoxypropylene diol (manufactured by Asahi Glass Co., Ltd., PML S4015, weight average molecular weight 15,000) 1000 parts by weight, isophorone diisocyanate 24.6 parts by weight (NCO / OH Ratio = 1.7) and 0.05 parts by weight of dibutyltin dilaurate were charged and reacted at 85 ° C. for 7 hours in a nitrogen atmosphere to obtain a urethane prepolymer.

(3) Synthesis of terminal silyl group polymer Next, 42.1 parts by weight of the silane compound as the resulting silylating agent was added to 1000 parts by weight of the obtained urethane prepolymer, and at 80 ° C. in a nitrogen atmosphere. It was made to react for 1 hour and the terminal silyl group polymer was obtained.
At this time, the progress of the reaction was confirmed by the disappearance of the isocyanate group absorption (2265 cm ⁻¹ ) by IR.
The obtained terminal silyl group polymer was a both-end silyl group polymer having a weight average molecular weight of 40,000 having terminal portions represented by the following formula (9) at both ends of polyoxypropylene as a main chain. It was.
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) Mixing Next, 100 parts by weight of ethyl acetate as a solvent and 100 parts by weight of completely hydrogenated terpene phenol resin (NHAS, manufactured by Yashara Chemical Co., Ltd.) as a tackifier resin with respect to 100 parts by weight of the obtained terminal silyl group polymer. Part was added and stirred until homogeneous to obtain a mixture.
Subsequently, 0.12 parts by weight of boron trifluoride monoethylamine complex as a catalyst and 3-aminopropyltrimethoxysilane (as a silane coupling agent) with respect to 100 parts by weight of the terminal silyl group polymer contained in the obtained mixture. 0.4 parts by weight of Shin-Etsu Chemical Co., Ltd. KBM-903) was added and stirred until uniform to obtain a pressure-sensitive adhesive composition before curing.
Hereinafter, the above-described tackifier resin may be abbreviated as “NH”.
Moreover, the FT-IR spectrum of the completely hydrogenated terpene phenol used is shown in FIG.

2. Application of Adhesive Composition Next, the obtained adhesive composition before curing was applied to both surfaces of a 25 μm thick polyester film (Lumirror T60 # 25, manufactured by Toray Industries, Inc.) by a knife coater method. Then, it dried at 100 degreeC for 1 minute, the coating layer with a thickness of 23 micrometers was formed, and the double-sided adhesive sheet was obtained.

  Similarly, after the obtained adhesive composition before curing was applied to one side of a polyester film having a thickness of 188 μm (manufactured by Toray Industries, Inc., Lumirror T50 # 188) by a knife coater method, at 100 ° C. It was dried for 1 minute to form a coating layer having a thickness of 23 μm to obtain a single-sided adhesive sheet for evaluation.

3. Seasoning of the pressure-sensitive adhesive composition Next, a laminate comprising the obtained coating layer of the pressure-sensitive adhesive composition before curing and a base material (polyester film) is allowed to stand in an environment of 23 ° C. and 50% RH for 14 days (seasoning). Then, the pressure-sensitive adhesive composition before curing was sufficiently cured, and the coating layer was used as a pressure-sensitive adhesive layer, and two types of the double-sided pressure-sensitive adhesive sheet of Example 1 and a single-sided pressure-sensitive adhesive sheet for evaluation were obtained.

4). Evaluation (1) Loss tangent (Tanδ)
From the obtained single-sided pressure-sensitive adhesive sheet for evaluation, a dynamic spectrum meter RDS (II) (Rheo at a frequency of 1 Hz in a pressure-sensitive adhesive obtained by removing a polyester film having a thickness of 188 μm, that is, a pressure-sensitive adhesive composition after undergoing a seasoning process. The loss tangent was calculated from the following equation (10) from the storage elastic modulus and loss elastic modulus measured using a metrics), and the temperature at which the loss tangent took a maximum value was measured. The obtained results are shown in Table 1.
Loss tangent (Tan δ) = loss modulus / storage modulus (10)

(2) Evaluation of adhesive force The adhesive force in the obtained double-sided pressure-sensitive adhesive sheet (one provided with a pressure-sensitive adhesive layer on both sides of the substrate) was measured.
That is, a 25 mm × 250 mm test piece was cut out from the obtained double-sided pressure-sensitive adhesive sheet, and one side of the cut-out double-sided pressure-sensitive adhesive sheet was bonded to a SUS # 360 plate using a 2 kg rubber roller, and immediately after bonding, 24 hours. , 23 ° C. and 50% RH in a standard environment.
Next, using a tensile tester (Orientec Co., Ltd., Tensilon), the double-sided PSA sheet after leaving was peeled from the SUS # 360 plate at a peeling speed of 300 mm / min and a peeling angle of 180 °. The measured peel load was defined as adhesive strength (N / 25 mm). The obtained results are shown in Table 1.

(3) Evaluation of constant load peeling characteristic The constant load peeling characteristic in the obtained double-sided pressure-sensitive adhesive sheet (one provided with a pressure-sensitive adhesive layer on one side) was evaluated.
That is, a 25 mm × 100 mm test piece was cut out from the obtained double-sided pressure-sensitive adhesive sheet, and a pressure-sensitive adhesive layer surface of 50 mm (25 mm × 50 mm = 1250 mm ^{2 in} area) from the edge of the cut-out double-sided pressure-sensitive adhesive sheet using a 2 kg rubber roller. It bonded together with respect to the SUS # 600 board, and was left to stand in the standard environment of 23 degreeC and 50% RH for 24 hours immediately after bonding.
Next, the test piece after standing was placed with the double-sided pressure-sensitive adhesive sheet attached side down, and the end of the double-sided pressure-sensitive adhesive sheet was subjected to a load of 200 g in the vertical (downward) direction, and maintained for 24 hours. Then, the distance (peeling distance, mm) at which the double-sided PSA sheet was peeled from the SUS plate surface was measured. The obtained results are shown in Table 1.
In addition, when 24 hours passed from the start of measurement, when the test piece was completely peeled off from the SUS plate and dropped, it was described as “falling” in Table 1.

(4) Evaluation of gel fraction From the obtained single-sided PSA sheet for evaluation, the pressure-sensitive adhesive from which the polyester film having a thickness of 188 μm was removed, that is, the gel fraction of the PSA composition after curing through the seasoning process was measured. did.
That is, the pressure-sensitive adhesive was immersed in ethyl acetate for 120 hours in an environment of 23 ° C. and 50% RH, dried at 100 ° C. for 30 minutes, and the weight before and after immersion was substituted into the following formula (11) to obtain the gel content. The rate was calculated. The obtained results are shown in Table 1.
Gel fraction (%) = (weight after immersion / weight before immersion) × 100 (11)

[Example 2]
In Example 2, a double-sided PSA sheet was produced and evaluated in the same manner as in Example 1 except that the amount of tackifying resin was changed to 90 parts by weight when adjusting the PSA composition. The obtained results are shown in Table 1.

[Example 3]
In Example 3, a double-sided PSA sheet was produced and evaluated in the same manner as in Example 1 except that the amount of the tackifying resin was changed to 80 parts by weight when adjusting the PSA composition. The obtained results are shown in Table 1.

[Example 4]
In Example 4, when preparing the pressure-sensitive adhesive composition, the tackifying resin was mixed with 50 parts by weight of completely hydrogenated terpene phenol (manufactured by Yashara Chemical Co., NH) and 50 parts by weight of partially hydrogenated terpene phenol (manufactured by Yashara Chemical Co., TH130). A double-sided PSA sheet was produced and evaluated in the same manner as in Example 1 except for changing to parts. The obtained results are shown in Table 1.
In the following, the above-described tackifier resin may be abbreviated as “TH130”.

[Example 5]
In Example 5, a double-sided PSA sheet was produced and evaluated in the same manner as in Example 1 except that the amount of tackifying resin was changed to 70 parts by weight when adjusting the PSA composition. The obtained results are shown in Table 1.

[Comparative Example 1]
In Comparative Example 1, a double-sided PSA sheet was produced in the same manner as in Example 1 except that the tackifying resin was changed to partially hydrogenated terpene phenol (Yasuhara Chemical Co., TH130) when adjusting the PSA composition. ,evaluated. The obtained results are shown in Table 1.
In the following, the above-described tackifier resin may be abbreviated as “TH130”.
Partially hydrogenated terpene phenol is a compound in which the terpene moiety is completely or almost hydrogenated.

[Comparative Example 2]
In Comparative Example 2, a double-sided PSA sheet was produced and evaluated in the same manner as in Example 1 except that the amount of tackifying resin was changed to 60 parts by weight when adjusting the PSA composition. The obtained results are shown in Table 1.

[Comparative Example 3]
In Comparative Example 3, a double-sided PSA sheet was produced in the same manner as in Example 1 except that the tackifying resin was changed to non-hydrogenated terpene phenol (Yasuhara Chemical Co., G125) when adjusting the PSA composition. evaluated. The obtained results are shown in Table 1.
In the following, the above-described tackifier resin may be abbreviated as “G125”.
In addition, the FT-IR spectrum of the non-hydrogenated terpene phenol used is shown in FIG.

[Comparative Example 4]
In Comparative Example 4, a double-sided PSA sheet was produced and evaluated in the same manner as in Example 1 except that no tackifier was added. The obtained results are shown in Table 1.

As described above in detail, according to the present invention, a predetermined tackifying resin is added to a predetermined terminal silyl group polymer at a predetermined blending ratio, and obtained by measuring the dynamic viscoelasticity of the pressure-sensitive adhesive layer. By setting the maximum value of the loss tangent to a value within a predetermined range, the balance between the adhesive force and the cohesive force in the pressure-sensitive adhesive composition is improved, and excellent constant load peeling characteristics can be obtained.
As a result, even when the cohesive force of the pressure-sensitive adhesive layer is relatively high, excellent constant load peeling characteristics can be exhibited, so that excellent adhesion reliability can be obtained.
Therefore, the double-sided pressure-sensitive adhesive sheet of the present invention is expected to be used as a highly reliable double-sided pressure-sensitive adhesive sheet in home appliances, automobiles, office automation equipment, and the like.
In particular, for example, 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.

2: base material, 4: coating layer, 88 ': release sheet, 10: polymer skeleton, 12: main chain of molecule, 14 (14a, 14b): isocyanate group, 20: silylating agent, 22: active hydrogen group, 24: Hydrolyzable silyl group, 30, 30 ′, 30 ″: Terminal silyl group polymer, 32 (32a, 32b): Terminal silyl group polymer terminal portion, 40, 40 ′: Adhesive layer, 50: Other adhesive Agent layer, 100: double-sided PSA sheet, 200: adherend

Claims (7)

A double-sided pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a cured product of a pressure-sensitive adhesive composition on both surfaces of a substrate,
The pressure-sensitive adhesive composition of at least one pressure-sensitive adhesive layer contains at least a terminal silyl group polymer as the component (A) and a tackifying resin as the component (B),
The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, a urethane bond and / or a urea bond in a part of the main chain or a side chain, or one of these, And having hydrolyzable silyl groups represented by the following general formula (1) at both ends of the main chain,
The tackifier resin of the component (B) contains a fully hydrogenated terpene phenol resin, and the blending amount of the tackifier resin is 100 parts by weight of the terminal silyl group polymer which is the component (A). , A value within the range of 70 to 140 parts by weight,
And,
The blending amount of the fully hydrogenated terpene phenol resin is a value within the range of 30 to 100% by weight with respect to the total amount (100% by weight) of the tackifying resin as the component (B),
Furthermore, the maximum value of the loss tangent (tan σ) obtained by dynamic viscoelasticity measurement (frequency: 1 Hz) of the pressure-sensitive adhesive layer is set to a value in the range of −10 to 15 ° C. .

(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.) A double-sided pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a cured product of a pressure-sensitive adhesive composition without including a base material,
The pressure-sensitive adhesive composition contains at least a terminal silyl group polymer as the component (A) and a tackifying resin as the component (B),
The terminal silyl group polymer as the component (A) has a polyoxyalkylene structure in the main chain, a urethane bond and / or a urea bond in a part of the main chain or a side chain, or one of these, And having hydrolyzable silyl groups represented by the following general formula (1) at both ends of the main chain,
The tackifier resin of the component (B) contains a fully hydrogenated terpene phenol resin, and the blending amount of the tackifier resin is 100 parts by weight of the terminal silyl group polymer which is the component (A). , A value within the range of 70 to 140 parts by weight,
And,
The blending amount of the fully hydrogenated terpene phenol resin is a value within the range of 30 to 100% by weight with respect to the total amount (100% by weight) of the tackifying resin as the component (B),
Furthermore, the double-sided pressure-sensitive adhesive sheet , wherein a maximum value of loss tangent (tan σ) obtained by dynamic viscoelasticity measurement (frequency: 1 Hz) of the pressure-sensitive adhesive layer is set to a value within a range of −10 to 15 ° C.

(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 contains, as the component (C), a catalyst for accelerating the curing of the terminal silyl group polymer as the component (A), and the catalyst includes an aluminum catalyst, a titanium catalyst, and a zirconium catalyst. The double-sided pressure-sensitive adhesive sheet according to claim 1, wherein the double-sided pressure-sensitive adhesive sheet is at least one selected from the group consisting of a bismuth-based catalyst and a boron trifluoride-based catalyst.   The double-sided pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive composition contains a silane coupling agent having an amino group in the molecule as the component (D).   The gel fraction of the pressure-sensitive adhesive layer measured by an immersion method (solvent: ethyl acetate, temperature: 23 ° C, time: 120 hours) is set to a value within a range of 30 to 70%. Double-sided adhesive sheet as described in any one of 1-4. A double-sided pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a cured product of a pressure-sensitive adhesive composition on both sides of a substrate, the method comprising the following steps (1) to (3): Manufacturing method.
(1) The terminal silyl group polymer as the component (A) and the tackifier resin as the component (B) are included, and the terminal silyl group polymer as the component (A) Hydrolysis represented by the following general formula (1), having an oxyalkylene structure, having a urethane bond and / or a urea bond in a part of the main chain or a side chain, and at either end of the main chain And the tackifier resin of the component (B) contains a fully hydrogenated terpene phenol-based resin, and the blending amount of the tackifier resin is adjusted to the end of the component (A). The total amount of the tackifying resin as the component (B) is set to a value within a range of 70 to 140 parts by weight with respect to 100 parts by weight of the silyl group polymer, and the blending amount of the completely hydrogenated terpene phenol resin is the component (B). (100 Relative to the amount%), laminating a preparation for step (2) said adhesive composition a pressure-sensitive adhesive composition to a value within the range of 30 to 100 wt%, on at least one side of the substrate (3 ) The pressure-sensitive adhesive composition is cured, and the maximum value of loss tangent (tan σ) obtained by dynamic viscoelasticity measurement (frequency: 1 Hz) of the pressure-sensitive adhesive layer is set to a value in the range of −10 to 15 ° C. Process

(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.) A double-sided pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of a cured product of a pressure-sensitive adhesive composition and comprising the following steps (1) to (3): Manufacturing method.
(1) The terminal silyl group polymer as the component (A) and the tackifier resin as the component (B) are included, and the terminal silyl group polymer as the component (A) Hydrolysis represented by the following general formula (1), having an oxyalkylene structure, having a urethane bond and / or a urea bond in a part of the main chain or a side chain, and at either end of the main chain And the tackifier resin of the component (B) contains a fully hydrogenated terpene phenol-based resin, and the blending amount of the tackifier resin is adjusted to the end of the component (A). The total amount of the tackifying resin as the component (B) is set to a value within a range of 70 to 140 parts by weight with respect to 100 parts by weight of the silyl group polymer, and the blending amount of the completely hydrogenated terpene phenol resin is the component (B). (100 Relative to the amount%), the value and the pressure-sensitive adhesive composition prepared step (2) the pressure-sensitive adhesive composition in the range 30 to 100 wt%, a step of laminating the surface of the release substrate (3) the The pressure-sensitive adhesive composition is cured to form a pressure-sensitive adhesive layer, and the maximum value of loss tangent (tan σ) obtained by dynamic viscoelasticity measurement (frequency: 1 Hz) of the obtained pressure-sensitive adhesive layer is −10 to 15 Processes with values in the range of ° C

(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.)

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