TW202104482A - Adhesive sheet and laminate excellent in handleability even when heat treatment is performed - Google Patents

Abstract

The object of the present invention is to provide an adhesive sheet excellent in handleability even when heat treatment is performed. The solution of the present invention is an adhesive sheet which at least includes an adhesive layer. The aforementioned adhesive sheet is used to fix a workpiece to a substrate through the aforementioned adhesive layer during the manufacturing process and the workpiece is peeled off from the adhesive layer after completion of the manufacturing process. The adhesive layer is composed of an active energy ray curable adhesive. When the initial adhesive force of the adhesive sheet is set to F0 and the adhesive force of the adhesive sheet after being heated at 150 DEG C for 30 minutes and then further irradiated with active energy rays is set to F2, the ratio of the adhesive force F2 to the initial adhesive force F0 (F2/F0) is 0.3 or less.

Description

Adhesive sheet and laminate

The present invention relates to an adhesive sheet suitable for fixing and peeling a work and a laminate using the adhesive sheet.

As a device (device) such as optical components and electronic components of the workpiece (workpiece), in the process of processing, assembly (layering), inspection, etc., the device is fixed to the substrate by the adhesive layer of the adhesive sheet (Base) steps. Then, after the end of the manufacturing process, the above-mentioned workpiece is peeled off the substrate.

As the adhesive layer as described above, Patent Document 1 discloses an adhesive layer in which the adhesive force is reduced by irradiating ultraviolet rays under a predetermined condition. In the case of using this adhesive layer, after the process is completed, by irradiating the adhesive layer with ultraviolet rays under predetermined conditions, the adhesive force to the workpiece can be reduced, thereby making it easier to peel the workpiece from the substrate. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2000-275625

[The problem to be solved by the invention]

By the way, in the above-mentioned process, sometimes the workpiece is heated while the workpiece is fixed to the substrate by the adhesive layer, or the workpiece is heated together (hereinafter, sometimes these The treatment is collectively referred to as "heat treatment").

In the above-mentioned heating treatment, the adhesive layer is also heated together with the workpiece, but the adhesiveness of the adhesive layer subjected to this heating treatment to the workpiece becomes too high. Therefore, although the adhesive sheet with the conventional adhesive layer disclosed in Patent Document 1 can be used in a process including heat treatment, it does not show that the work can be easily peeled off by irradiating active energy rays after the process is completed. Kind of excellent operability.

In view of the above-mentioned circumstances, the object of the present invention is to provide an adhesive sheet excellent in handleability even when heat treatment is performed, and a laminate using the adhesive sheet. [Means used to solve the problem]

In order to achieve the above object, the present invention provides an adhesive sheet, which is an adhesive sheet including at least an adhesive layer, wherein the adhesive sheet is used to fix the workpiece on the substrate through the adhesive layer during the manufacturing process and to fix the workpiece after the process is completed. Use for peeling from the adhesive layer, and the adhesive layer is composed of an active energy ray-curable adhesive, and the initial adhesive force of the adhesive sheet is set to F ₀ and heated at 150°C for 30 minutes Then, when the adhesive force of the adhesive sheet is F ₂ after further irradiation with active energy rays, the ratio of the adhesive force F ₂ to the initial adhesive force F _{0 (F 2} /F ₀ ) is 0.3 or less (Invention 1).

In the above invention (Invention 1), since the adhesive layer is composed of an active energy ray-curable adhesive, the ratio of the _{adhesive force F 2} to the initial adhesive force F _{0 (F 2} /F ₀ ) is within the above range Therefore, it is possible to use the adhesive force of the adhesive layer to firmly fix the workpiece on the substrate. Even if the workpiece is heat-treated, the adhesive layer can be subsequently irradiated with a predetermined condition of active energy The radiation makes the adhesive force of the adhesive layer drop well, so that the workpiece can be easily peeled off the substrate.

In the above invention (Invention 1), after the adhesive layer is irradiated with active energy rays, the storage elastic modulus of the adhesive layer at 23° C. is preferably 0.1 MPa or more and 2 MPa or less (Invention 2).

In the above inventions (Inventions 1 and 2), the active energy ray-curable adhesive preferably includes a silane coupling agent (Invention 3).

In the above inventions (Inventions 1 to 3), the aforementioned initial adhesive force F _{0 is} preferably 0.5 N/25 mm or more and 80 N/25 mm or less (Invention 4).

After heating at 150 deg.] C in the above inventions (Inventions 1 to 4) for 30 minutes the adhesion of the adhesive sheet F. ₁ to 0.5N / 25mm or more, 80N / 25mm or less preferably (Invention 5).

In the above inventions (Inventions 1 to 5), the aforementioned adhesive force F _{2 is} preferably 0.01 N/25 mm or more and 8 N/25 mm or less (Invention 6).

In the above inventions (Inventions 1 to 6), the aforementioned workpiece is preferably a flexible device (Invention 7).

In the aforementioned inventions (Inventions 1 to 7), the aforementioned application preferably includes heating of the aforementioned workpiece fixed on the aforementioned substrate (Invention 8).

In the above inventions (Inventions 1 to 8), the adhesive sheet preferably includes two release sheets, and the adhesive layer is sandwiched between the release sheets and contacts the release surfaces of the two release sheets (Invention 9).

Next, the present invention provides a laminate in which a flexible device, the adhesive layer of the adhesive sheet (Inventions 1 to 9), and a substrate are laminated in this order (Invention 10). [Effects of the invention]

According to the pressure-sensitive adhesive sheet of the present invention, even in the case of heat treatment, it has excellent operability. Furthermore, the laminate according to the present invention has excellent operability.

Hereinafter, an embodiment of the present invention will be described. The adhesive sheet according to an embodiment of the present invention includes at least an adhesive layer, and it is preferably an adhesive sheet formed by laminating a release sheet on one or both sides of the adhesive layer.

The adhesive sheet according to this embodiment is used for the purpose of fixing the workpiece (workpiece) to the substrate through the adhesive layer during the manufacturing process, and peeling the workpiece from the adhesive layer after the process is completed. In particular, the adhesive sheet according to this embodiment is suitable for processing, assembling (laminating), and inspecting devices such as optical components and electronic components as workpieces. The layer is fixed to the substrate. In addition, the above-mentioned substrate is used to support and fix the workpiece during the manufacturing process, and also includes concepts such as a base.

The workpiece is not particularly limited, but a flexible device such as an optical component or electronic component having flexibility is preferable. Furthermore, a workpiece including a heating process in the above-mentioned manufacturing process can also be used as the above-mentioned workpiece. As such a heating process, for example, a metal vapor deposition process for forming a wiring of a transparent electrode, a resin curing process, etc. can be cited. From these viewpoints, as the workpiece, for example, a flexible organic light emitting diode (OLED) device, a flexible liquid crystal device, etc. are preferred, and a flexible OLED device is particularly preferred.

The thickness of the workpiece is not particularly limited. It is preferably a thickness that easily exhibits flexibility. Specifically, 5 μm or more is preferable, 15 μm or more is more preferable, 30 μm or more is particularly preferable, and 40 μm or more is more preferable good. Furthermore, the thickness of the workpiece is preferably 5000 μm or less, preferably 2000 μm or less, particularly preferably 1000 μm or less, and more preferably 500 μm or less.

Furthermore, as the shape of the workpiece in a plan view, it may be circular or polygonal, and polygonal is preferable. When the shape of the workpiece in a plan view is a polygon, the total number of sides constituting the polygon is not particularly limited, and 3 sides or more are preferable, and 4 sides or more are particularly preferable. Furthermore, the total number of sides constituting the polygon is preferably 10 sides or less, and particularly preferably 6 sides or less. Among them, when the shape of the workpiece in a plan view is a polygon, this polygon is particularly preferably a quadrilateral formed by four sides.

Furthermore, when the shape of the workpiece in a plan view is a polygon, the lengths of the sides constituting the polygon may all have the same length or different lengths. When the shape of the workpiece in a plan view is a quadrilateral, it is preferable that the sides on the opposite sides are parallel to each other, and a rectangle with long sides and short sides is preferable. In this case, the length of the long side is preferably 10 mm or more, particularly preferably 40 mm or more, and more preferably 80 mm or more. Furthermore, the length of the aforementioned long side is preferably 1500 mm or less, particularly preferably 800 mm or less, and more preferably 500 mm or less. On the other hand, the length of the short side is preferably 5 mm or more, particularly preferably 10 mm or more, and more preferably 20 mm or more. Furthermore, the length of the short side is preferably 1000 mm or less, particularly preferably 600 mm or less, and more preferably 350 mm or less.

Furthermore, as a substrate, as long as the workpiece can be fixed on it by the adhesive layer of the adhesive sheet, it is not particularly limited, but it will not be produced even if the heat treatment is performed in the above process. A substrate that is deformed or changed in appearance is preferred. Furthermore, the workpiece is adhered to the substrate by the adhesive layer of the adhesive sheet, and in the above-mentioned process and the process of peeling the workpiece, the adhesive layer and the substrate must be sufficiently fixed. For example, if the surface of the substrate is rough, the adhesion between the substrate and the adhesive layer is reduced, and the adhesive layer may be accidentally peeled from the substrate during the manufacturing process. Therefore, it is better for the substrate to have a smooth surface on the fixed side of the workpiece. From these viewpoints, it is particularly preferable to use a glass substrate as a substrate.

In the adhesive sheet according to this embodiment, the adhesive layer is composed of an active energy ray-curable adhesive. Moreover, when the initial adhesive force of the adhesive sheet according to the present embodiment is F ₀ , and the adhesive force of the adhesive sheet after heating at 150° C. for 30 minutes and then further irradiated with active energy rays is F ₂ , the adhesive The ratio of the force F ₂ to the initial adhesive force F _{0 (F 2} /F ₀ ) is 0.3 or less.

By setting the above-mentioned adhesive force ratio (F ₂ /F ₀ ) to 0.3 or less, the workpiece can be well fixed on the substrate, and after the end of the process, active energy rays are irradiated to the adhesive layer to make the adhesive layer sufficiently Hardening can reduce the adhesion of the adhesive layer to the workpiece. As a result, the workpiece can be easily peeled from the substrate. In particular, even in the case where the above-mentioned process includes heat treatment of the workpiece, when the workpiece is peeled from the substrate, the adhesive force has been sufficiently reduced, and the workpiece can be easily peeled from the substrate. In this way, the adhesive sheet according to this embodiment has excellent operability.

On the other hand, when the above-mentioned adhesive force ratio (F ₂ /F ₀ ) exceeds 0.3, even if the adhesive layer is irradiated with active energy rays after the end of the process, the adhesive force of the adhesive layer to the workpiece is not sufficiently reduced, resulting in the workpiece It becomes difficult to peel from the substrate. From the viewpoint of effectively avoiding this problem, the above-mentioned adhesive force ratio (F ₂ /F ₀ ) is preferably 0.15 or less, particularly preferably 0.08 or less, more preferably 0.05 or less, and most preferably 0.04 or less. In addition, the lower limit of the above-mentioned adhesive force ratio (F ₂ /F ₀ ) is not particularly limited, and may be, for example, 0.001 or more, particularly 0.01 or more, and further, 0.015 or more.

In the adhesive sheet according to this embodiment, the aforementioned initial adhesive force F _{0 is} preferably 0.5N/25mm or more, preferably 1.5N/25mm or more, more preferably 3N/25mm or more, and 6N/25mm or more Especially good, and from the viewpoint of improving durability (especially blister resistance), 8N/25mm or more is preferred, 10N/25mm or more is more preferred, and 13N/25mm or more is most preferred. Furthermore, the initial adhesion F _{0 is} preferably 80N/25mm or less, preferably 60N/25mm or less, particularly preferably 50N/25mm or less, more preferably 35N/25mm or less, and 20N/25mm or less as optimal. By setting the initial adhesive force F ₀ to fall within the aforementioned range, it becomes easy to _{adjust the adhesive force ratio (F 2} /F ₀ ) to fall within the aforementioned range. Furthermore, especially by setting the initial adhesive force F ₀ to 3N/25mm or more, it becomes easy and good to hold the workpiece on the adhesive layer during the manufacturing process.

In the adhesive sheet according to this embodiment, the adhesive force F _{1 of the} aforementioned adhesive sheet after heating at 150°C for 30 minutes is 0.5N/25mm or more, preferably 1N/25mm or more, and particularly preferably 5N/25mm or more , 10N/25mm or more is more preferable, and from the viewpoint of improving durability (especially blistering resistance), 14N/25mm or more is preferable, and 17N/25mm or more is particularly preferable. Furthermore, the adhesion force F _{1 is} preferably 80N/25mm or less, preferably 50N/25mm or less, and 35N/25mm or less is particularly preferable, and from the viewpoint of improving durability (especially blistering resistance), 22N/25mm or less is more preferable. By setting the adhesive force F ₁ to fall within the above-mentioned range, it becomes easy to _{adjust the adhesive force ratio (F 2} /F ₀ ) to fall within the above-mentioned range. Furthermore, in particular by the adhesive force F ₁ to 5N / 25mm or more, even when the heat treatment after the workpiece or substrate outgassing generated (outgas), can be effectively suppressed in outgassing adhesive layer The floating or peeling caused by the interface with the workpiece or the substrate.

In the adhesive sheet according to this embodiment, the aforementioned adhesive force F _{2 is} preferably 0.01N/25mm or more, preferably 0.05N/25mm or more, particularly preferably 0.1N/25mm or more, and 0.2N/25mm The above is better. Furthermore, from the viewpoint of making it easier to peel the workpiece from the substrate well, the adhesive force F _{2 is} preferably 8N/25mm or less, 4N/25mm or less, and 2N/25mm or less is particularly preferred. 1N/25mm or less is more preferable, and 0.5N/25mm or less is the best. By setting the adhesive force F ₂ to fall within the above range, it becomes easy to _{adjust the adhesive force ratio (F 2} /F ₀ ) to fall within the above range.

In the adhesive sheet according to this embodiment, the ratio (F ₂ /F _{1 ) of the aforementioned adhesive force F 2} to the aforementioned adhesive force F ₁ is preferably 0.3 or less, preferably 0.15 or less, and particularly preferably 0.08 or less And from the viewpoint of improving durability (especially foam resistance), 0.04 or less is more preferable. Furthermore, the ratio (F ₂ /F ₁ ) is preferably 0.001 or more, particularly preferably 0.01 or more, and from the viewpoint of improving durability (especially blistering resistance), it is more preferably 0.015 or more. By setting (F ₂ /F ₁ ) to fall within these ranges, it becomes easy to _{adjust the adhesive force ratio (F 2} /F ₀ ) to fall within the aforementioned range.

In the adhesive sheet according to this embodiment, the ratio (F ₁ /F _{0 ) of the aforementioned adhesive force F 1} to the aforementioned initial adhesive force F ₀ is preferably 2.5 or less, particularly preferably 1.8 or less, and 1.4 or less Better. Furthermore, the ratio (F ₁ /F ₀ ) is preferably 0.98 or more, preferably 1.0 or more, particularly preferably 1.1 or more, and more preferably 1.15 or more. By setting (F ₁ /F ₀ ) to fall within these ranges, it becomes easy to _{adjust the adhesive force ratio (F 2} /F ₀ ) to fall within the aforementioned range.

Here, the aforementioned initial adhesive force F ₀ , adhesive force F ₁ , and adhesive force F _{2 are} basically the adhesive force measured by the 180-degree peeling method according to JISZ0237:2009, and these adhesive force measurement methods The details are as described in the test examples described later.

In the adhesive sheet according to this embodiment, from the viewpoint of operability, especially the fixation of the workpiece in the process, the adhesion to glass at 23°C is preferably 24N/25mm or more, and 28N/25mm or more is particularly preferable , And more preferably 32N/25mm or more. On the other hand, from the viewpoint of reworkability, the upper limit of the adhesion to glass at 23°C is preferably 100N/25mm or less, particularly preferably 76N/25mm or less, and 52N/25mm The following is better.

Here, the above-mentioned adhesive force to glass is basically the adhesive force measured by the 180-degree peel method specified in JIS Z0237:2009, and the width of the measurement sample is set to 25mm and the length is set to 100mm. This measurement The sample is attached to the adherend and pressurized at 0.5 MPa and 50°C for 20 minutes, and then placed under normal pressure, predetermined temperature, and 50% RH for 24 hours, and then peeled off at 300 mm/min Measure to get the above-mentioned adhesive force. Furthermore, the "adhesion to glass" in this specification means the adhesion to soda lime glass.

In the adhesive sheet of the present embodiment, after the irradiation of an active energy ray adhesive layer, this adhesive layer a storage elastic modulus G 'at 23 ℃ of ₂ or more preferably 0.1MPa to 0.3MPa or more is more Preferably, 0.4 MPa or more is particularly preferable, and 0.42 MPa or more is more preferable. By setting the storage elastic modulus G′ ₂ to be 0.1 MPa or more, the adhesive layer after irradiation with active energy rays is cured well, and it becomes easier to peel the work after the process from the substrate. In addition, the upper limit of the storage elastic modulus G′ ₂ is not particularly limited, and may be, for example, 2 MPa or less, particularly 1 MPa or less, and further, 0.5 MPa or less.

Further, in the adhesive sheet of the present embodiment, the adhesive agent layer before the irradiation of an active energy ray, this adhesive layer a storage elastic modulus G 'at 23 ℃ apos more preferably ₁ to 0.01MPa to 0.03MPa The above is particularly preferable, and more preferably 0.05 MPa or more. Furthermore, the storage elastic modulus _{G'1 is preferably 1} MPa or less, particularly preferably 0.5 MPa or less, and more preferably 0.1 MPa or less. With the storage modulus of the adhesive layer prior to irradiation with an active energy ray G _'1 is set between these ranges, it becomes easy to work effectively fixed on the substrate, and the adhesion after irradiation with active energy rays storage elastic modulus of the adhesive layer G _'2 can be easily adjusted to between above range.

Further, in the adhesive sheet of the present embodiment, the above-described storage elastic modulus G _'2 with respect to the storage elastic modulus G' of Comparative Example ₁ (G _'2 / G' ₁₎ or more preferably 2 to 4 The above is preferable, 5 or more is particularly preferable, and 6 or more is more preferable. By setting the above-mentioned ratio (G' ₂ /G' ₁ ) to 2 or more, the degree of hardening of the adhesive layer according to the present embodiment by irradiating active energy rays becomes more obvious, and it becomes easier to achieve a high degree of compatibility with Good adhesion of the workpiece and substrate before active energy rays, and peelability after active energy rays irradiation. In addition, the upper limit of the above-mentioned ratio (G' ₂ /G' ₁ ) is not particularly limited. For example, it may be 20 or less, particularly 12 or less, and further, 8 or less.

Further, the storage elastic modulus above-described adhesive layer after irradiation with active energy rays at 23 ℃ the G 'storage modulus _1, and the adhesive layer prior to irradiation with an active energy ray at 23 ℃, G' ₂ of The details of the measurement methods are as described in the test examples described later.

In the adhesive sheet according to this embodiment, with respect to the gel fraction G ₁ of the adhesive layer before the active energy ray is irradiated to the adhesive layer, the gel fraction of the adhesive layer after the active energy ray is irradiated to the adhesive layer The ratio of the glue fraction G _{2 (G 2} /G ₁ ) is preferably 1.00 or more, particularly preferably 1.05 or more, and more preferably 1.10 or more. By setting the above-mentioned ratio (G ₂ /G ₁ ) to 1.00 or more, the degree of hardening of the adhesive layer according to the present embodiment by irradiation with active energy rays becomes more pronounced, and it becomes easier to achieve a high degree of compatibility with active energy irradiation. Good adhesion to the workpiece and substrate before irradiation, and peelability after active energy ray irradiation. In addition, the _{upper limit of the aforementioned ratio (G 2} /G ₁ ) is not particularly limited. For example, it is preferably 1.5 or less, particularly preferably 1.2 or less, and more preferably 1.14 or less.

In the adhesive sheet according to this embodiment, the gel fraction G ₁ is preferably 40% or more, preferably 60% or more, particularly preferably 70% or more, more preferably 80% or more, and 86% % Or more is the best. Furthermore, the aforementioned gel fraction G ₁ is preferably 99% or less, preferably 95% or less, particularly preferably 92% or less, and more preferably 89% or less. By setting the gel fraction G ₁ to fall within the aforementioned range, the aforementioned ratio (G ₂ /G ₁ ) can be easily adjusted to fall within the aforementioned range.

Furthermore, in the adhesive sheet according to this embodiment, the above-mentioned gel fraction G ₂ is preferably 85% or more, more preferably 90% or more, particularly preferably 95% or more, and more preferably 99% or more good. Furthermore, the above-mentioned gel fraction G ₂ is preferably 100% or less, particularly preferably 99.8 or less, and more preferably 99.7% or less. By setting the gel fraction G ₂ to fall within the above range, the above ratio (G ₂ /G ₁ ) can be easily adjusted to fall within the above range.

Here, the details of the method for measuring the gel fraction G ₁ and the gel fraction G ₂ are as described in the test examples described later, respectively.

Suitable for the work piece of the adhesive sheet according to this embodiment, the surface area in contact with the adhesive layer of the adhesive sheet is suitably 10000 cm ² or less, more suitably 5000 cm ² or less, especially 2500 cm ² or less, more suitable for 1000 cm ² or less, and most preferably 200 cm ² or less. Furthermore, the area is suitably 9 cm ² or more, particularly suitably 16 cm ² or more, and more suitably 25 cm ² or more. Generally, the smaller the contact area with the adhesive layer, the more difficult it is to hold the workpiece on the adhesive layer. However, according to the adhesive sheet of this embodiment, even if the above-mentioned area is 10000 cm ² or less, the workpiece can be held well on the adhesive layer. On the adhesive layer. In addition, generally, the larger the contact area with the adhesive layer, the greater the peeling force is required when the workpiece is peeled from the adhesive layer. However, according to the adhesive sheet of this embodiment, even if the above-mentioned area is 9 cm ² or more , It is also possible to easily separate the workpiece from the adhesive layer by the irradiation of active energy rays.

FIG. 1 illustrates the specific structure as an example of the adhesive sheet according to this embodiment. As shown in FIG. 1, the adhesive sheet 1 according to one embodiment is composed of two release sheets 12a and 12b, and the two release sheets 12a, 12b sandwiched between the two release sheets 12a, 12b and contact the release surfaces of the two release sheets 12a, 12b. The adhesive layer 11 is formed. In addition, the peeling surface of the peeling sheet in this specification means the peelable surface in the peeling sheet, and it also includes any one of the surface that has been subjected to peeling treatment and the surface that can exhibit peelability without peeling treatment. By.

1. Parts 1-1. Adhesive layer The adhesive constituting the adhesive layer 11 of the adhesive sheet 1 according to the present embodiment is not particularly limited as long as it has active energy ray curability and also satisfies the aforementioned physical properties. As such an active energy ray-curable adhesive, it may include an adhesive that has active energy ray-curable properties (active energy ray-curable polymer) as a main component, or it may include an adhesive that does not have active energy ray-curable properties. A mixture of a polymer (active energy ray non-curable polymer) and a monomer and/or oligomer having at least one active energy ray hardenable group as the main component of the adhesive.

Among them, from the viewpoint of easily satisfying the aforementioned physical properties, the adhesive constituting the adhesive layer 11 in this embodiment is preferably an adhesive including an active energy ray curable polymer as a main component. In particular, the adhesive constituting the adhesive layer 11 contains (meth)acrylate (co)polymer (meth)acrylate (co)polymers with active energy ray-curable functional groups (active energy ray-curable groups) introduced into the side chains ( A) (hereinafter sometimes referred to as "active energy ray curable polymer (A)") as an adhesive composition of the above active energy ray curable polymer and crosslinking agent (B) (hereinafter sometimes referred to as " Adhesive formed by adhesive composition P") (adhesive formed by crosslinking adhesive composition P) is preferable. In addition, in this specification, the (meth)acrylic system means both acrylic acid and methacrylic acid. The same goes for other similar terms. Furthermore, "polymer" also includes the concept of "copolymer".

(1) Components of adhesive composition P (1-1) Active energy ray-curable polymer (A) Active energy ray-curable polymer (A) such that an acrylic copolymer (a1) having a functional group-containing monomer unit and an unsaturated group-containing compound having a functional group capable of bonding to the above-mentioned functional group ( a2) The polymer obtained by the reaction is preferred.

The aforementioned acrylic copolymer (a1) preferably contains a structural unit derived from a monomer containing a functional group and a structural unit derived from an alkyl (meth)acrylate monomer or a derivative thereof. In addition, as described above, the functional group of the functional group-containing monomer is used not only for the reaction with the unsaturated group-containing compound (a2), but also for the reaction with the crosslinking agent (B) described later. . When the reaction with the cross-linking agent (B) occurs, a cross-linked structure (three-dimensional grid structure) is formed in the adhesive, and the desired cohesion is obtained.

As a monomer containing a functional group in the structural unit of the acrylic copolymer (a1), a monomer having a functional group such as a polymerizable double bond, a hydroxyl group, a carboxyl group, an amino group, a substituted amino group, and an epoxy group in the molecule Better.

Examples of monomers containing hydroxyl groups include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and (meth)acrylic acid. 2-hydroxybutyl, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc., and the above-mentioned materials may be used alone or in combination of two or more. Among the above, from the viewpoint of good reaction with the unsaturated group-containing compound (a2) and easy formation of the desired active energy ray-curable polymer (A), 4-hydroxy (meth)acrylic acid is used. Butyl ester and 2-hydroxyethyl (meth)acrylate are preferable, and from the viewpoint of making it easier to satisfy the aforementioned adhesive properties, it is particularly preferable to use 4-hydroxybutyl acrylate and 2-hydroxyethyl acrylate, and It is more preferable to use 4-hydroxybutyl acrylate.

Examples of the carboxyl group-containing monomer include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. The above-mentioned materials may be used alone or in combination of two or more kinds.

Examples of the amino group-containing monomer or the substituted amino group-containing monomer include aminoethyl (meth)acrylate, n-butylaminoethyl (meth)acrylate, and the like. The above-mentioned materials may be used alone or in combination of two or more kinds.

In the acrylic copolymer (a1), as the monomer unit constituting the polymer, the above-mentioned structural unit derived from the functional group-containing monomer preferably contains 5% by mass or more, and more preferably contains 10% by mass or more It is particularly preferable to contain 20% by mass or more, and it is more preferable to contain 26% by mass or more. Furthermore, in the acrylic copolymer (a1), as the monomer unit constituting the polymer, the above-mentioned structural unit derived from the functional group-containing monomer preferably contains 50% by mass or less, and preferably contains 40% by mass or less It is particularly preferable, and it is more preferable to contain 35% by mass or less. Since the content of the monomer unit constituting the polymer in the acrylic copolymer (a1) is within the above range, it becomes easy to form the desired active energy ray-curable polymer (A), and the resulting adhesive It also becomes easier to satisfy the aforementioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

As the alkyl (meth)acrylate monomer as the structural unit of the acrylic copolymer (a1), an alkyl (meth)acrylate monomer having an alkyl group with 1 to 20 carbon atoms is preferred. The alkyl group may be linear or branched, and may have a cyclic structure.

As the alkyl (meth)acrylate monomer having 1 to 20 carbon atoms in the above-mentioned alkyl group, particularly the alkyl (meth)acrylate monomer having 1 to 18 carbon atoms in the alkyl group, for example, It is preferable to use methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, etc., and it is particularly preferable to use methyl acrylate. The above-mentioned materials may be used singly or in combination of two or more kinds.

In the acrylic copolymer (a1), as the monomer unit constituting the polymer, the alkyl (meth)acrylate monomer having 1 to 18 carbon atoms in the alkyl group preferably contains 1% by mass or more. It is particularly preferable to contain 4% by mass or more, and it is more preferable to contain 8% by mass or more. Furthermore, in the acrylic copolymer (a1), as the monomer unit constituting the polymer, the alkyl (meth)acrylate monomer having 1 to 18 carbon atoms in the alkyl group contains 20% by mass or less Preferably, the content is 16% by mass or less, and the content is more preferably 12% by mass or less.

Furthermore, as an alkyl (meth)acrylic acid alkyl ester monomer with 1-20 carbon atoms, the glass transition temperature (Tg) as a homopolymer is -30°C or less (hereinafter sometimes referred to as "Low Tg alkyl acrylate") is better. Since such a low Tg alkyl acrylate is contained as a structural monomer unit, the resulting adhesive becomes easy to exhibit appropriate viscoelasticity. In this way, not only in a normal temperature environment, but even when the adhesive is exposed to high temperatures, it becomes easier to obtain the desired adhesive force, and it becomes easier to satisfy the aforementioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

As preferred examples of low Tg alkyl acrylates, for example, n-butyl acrylate (Tg-55°C), n-octyl acrylate (Tg-65°C), isooctyl acrylate (Tg-58°C), 2-ethylhexyl acrylate (Tg-70°C), isononyl acrylate (Tg-58°C), isodecyl acrylate (Tg-60°C), isodecyl methacrylate (Tg-41°C), N-dodecyl acrylate (Tg-65°C), tridecyl acrylate (Tg-55°C), tridecyl methacrylate (Tg-40°C), etc. Among them, as low Tg alkyl acrylates, alkyl acrylates having a homopolymer Tg of -45°C or less are preferred, and alkyl acrylates having a Tg of -50°C or less are particularly preferred. Specifically, n-butyl acrylate and 2-ethylhexyl acrylate are particularly preferred. The above-mentioned materials may be used alone or in combination of two or more kinds.

In addition, when two or more kinds of low Tg alkyl acrylates are used in combination, from the viewpoint that the workpiece can be easily peeled from the substrate after the end of the process, among the low Tg alkyl acrylates used The content of the lowest Tg is better.

In the acrylic copolymer (a1), as the monomer unit constituting the polymer, the low Tg alkyl acrylate preferably contains 35 mass% or more, particularly preferably 45 mass% or more, and 55 mass% % Or more is more preferable. Furthermore, in the acrylic copolymer (a1), as the monomer unit constituting the polymer, the low Tg alkyl acrylate preferably contains 90% by mass or less, particularly preferably 80% by mass or less, and It is more preferable to contain 70% by mass or less. Since the content of the aforementioned low-Tg alkyl acrylate is within the aforementioned range, the resulting adhesive can easily satisfy the aforementioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

Furthermore, in the acrylic copolymer (a1), it is also preferable to include a monomer containing a nitrogen atom as the monomer unit constituting the polymer. By including the monomer containing nitrogen atoms, it is possible to improve the adhesion with the adherend (substrate) such as glass. The monomer containing a nitrogen atom includes a monomer having an amino group, a monomer having an amide group, a monomer having a nitrogen-containing heterocyclic ring, and the like. Among them, a monomer having a nitrogen-containing heterocyclic ring is preferred. Furthermore, from the viewpoint of increasing the degree of freedom of the above-mentioned nitrogen atom-containing monomer derivation part in the higher structure of the formed adhesive, this nitrogen atom-containing monomer is in addition to forming the acrylic copolymer (a1) In addition to the one polymerizable group used in the polymerization, it is preferable that the reactive unsaturated double bond group is not included.

As the monomer having a nitrogen-containing heterocyclic ring, for example, N-(meth)acryloylmorpholine, N-vinyl-2-pyrrolidone, N-(meth)acryloylpyrrolidone, N-( (Meth)acrylic acid piperidine, N-(meth)acrylic acid pyrrolidine, N-(meth)acrylic acid aziridine, (meth)acrylic acid aziridinyl ethyl ester, 2-vinyl Pyridine, 4-vinylpyridine, 2-vinylpyrazine, 1-vinylimidazole, N-vinylcarbazole, N-vinylphthalimide, etc., among which, it can exert more excellent adhesion Strong N-(meth)acryloylmorpholine is preferred, and N-acryloylmorpholine is particularly preferred.

In addition, as the monomer containing a nitrogen atom, for example, (meth)acrylamide, N-methyl(meth)acrylamide, N-methylol(meth)acrylamide, N- Tert-butyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-ethyl(meth)acrylamide, N,N-dimethylaminopropyl (Meth)acrylamide, N-isopropyl(meth)acrylamide, N-phenyl(meth)acrylamide, dimethylaminopropyl(meth)acrylamide, N-ethylene Base caprolactam, (meth)acrylic acid-methylaminoethyl, (meth)acrylic acid-ethylaminoethyl, (meth)acrylic acid-methylaminopropyl, (meth)acrylic acid monoethylaminopropyl Ester, dimethylaminoethyl (meth)acrylate, etc.

The above nitrogen atom-containing monomers may be used singly or in combination of two or more kinds.

From the viewpoint of improving the adhesion to adherends such as glass, in the acrylic copolymer (a1), as the monomer unit constituting the polymer, the monomer containing a nitrogen atom contains 1% by mass or more Preferably, it is more preferable to contain 5% by mass, and it is particularly preferable to contain 8% by mass or more. Furthermore, from the viewpoint of ensuring the blending amount of other components, the content of the nitrogen atom-containing monomer is preferably 20% by mass or less, more preferably 16% by mass or less, and particularly preferably 12% by mass or less. Since the content of the above-mentioned nitrogen atom-containing monomer is within the above-mentioned range, the obtained adhesive becomes easy to satisfy the above-mentioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

General methods can be used to copolymerize the above-mentioned functional group-containing monomers with (meth)acrylate monomers or their derivatives to obtain acrylic copolymers (a1), and in addition to these monomers, Vinyl formate, vinyl acetate, styrene, etc. are copolymerized.

The acrylic copolymer (a1) is preferably a solution polymer obtained by a solution polymerization method. Because it is a solution polymer, it is easy to obtain a high molecular weight polymer, and because it has adhesive force at high temperatures, an excellent adhesive can be obtained.

The polymerization state of the acrylic copolymer (a1) may be a random copolymer or a block copolymer.

The unsaturated group-containing compound (a2) is not particularly limited as long as it has a functional group capable of reacting with the functional group of the functional group-containing monomer unit in the acrylic copolymer (a1). The functional group that the unsaturated group-containing compound (a2) has can be appropriately selected according to the type of the functional group that the acrylic copolymer (a1) has. For example, when the functional group of the acrylic copolymer (a1) is a hydroxyl group, an amino group, or a substituted amino group, as the functional group of the unsaturated group-containing compound (a2), an isocyanate group or an epoxy group is used as the functional group Preferably, when the functional group of the acrylic copolymer (a1) is an epoxy group, the functional group of the unsaturated group-containing compound (a2) is preferably an amino group, a carboxyl group or an azide group .

Furthermore, in the above-mentioned unsaturated group-containing compound (a2), it is preferable to contain at least one active energy ray polymerizable carbon-carbon double bond in one molecule, and it is particularly preferable to contain 1 to 6 carbon-carbon double bonds, and It is more preferable to include 1 to 4. As specific examples of such an unsaturated group-containing compound (a2), for example, 2-methacryloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate, formaldehyde Acrylic isocyanate, allyl isocyanate, 1,1-(bisacryloxymethyl) ethyl isocyanate; by diisocyanate compound or polyisocyanate compound, and hydroxyethyl (meth)acrylate Acrylic monoisocyanate compound obtained by the reaction; an acryl monoisocyanate compound obtained by reacting a diisocyanate compound or a polyisocyanate compound with a polyol compound and hydroxyethyl (meth)acrylate; (methyl) ) Glycidyl acrylate; (meth)acrylic acid, 2-(1-aziridinyl)ethyl (meth)acrylate, 2-vinyl-2-oxazoline, 2-isopropenyl-2-oxa Oxazoline and so on.

Relative to the number of moles of monomers containing functional groups in the acrylic copolymer (a1), the unsaturated group-containing compound (a2) is preferably used at a ratio of 50 mole% or more, and 60 mole% The above ratio is preferable, and it is particularly preferable to use a ratio of 70 mol% or more, and it is more preferable to use a ratio of 80 mol% or more, and it is most preferable to use a ratio of 88 mol% or more. Furthermore, with respect to the number of moles of monomers containing functional groups in the acrylic copolymer (a1), the unsaturated group-containing compound (a2) is preferably used in a ratio of 99 mole% or less, and 95% The ratio of mol% or less is particularly preferable, and it is more preferable to use a ratio of 92 mol% or less. Since the content of the above-mentioned unsaturated group-containing compound (a2) is within the above-mentioned range, the obtained adhesive becomes easy to satisfy the above-mentioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

The active energy ray-curable polymer (A) can be obtained by reacting the functional group of the unsaturated group-containing compound (a2) with the functional group of the aforementioned acrylic copolymer (a1).

In the reaction of the acrylic copolymer (a1) and the unsaturated group-containing compound (a2), the functional group of the acrylic copolymer (a1) and the function of the unsaturated group-containing compound (a2) can be The combination of groups, the reaction temperature, pressure, solvent, time, presence or absence of catalyst, and type of catalyst are appropriately selected. In this way, the functional group existing in the acrylic copolymer (a1) reacts with the functional group in the unsaturated group-containing compound (a2), and the unsaturated group is introduced into the side chain of the acrylic copolymer (a1), Furthermore, an active energy ray-curable polymer (A) was obtained.

The weight average molecular weight (Mw) of the active energy ray-curable polymer (A) obtained in the above manner is preferably 100,000 or more, preferably 200,000 or more, particularly preferably 400,000 or more, and 600,000 or more For better. Furthermore, the weight average molecular weight (Mw) is preferably 1.5 million or less, particularly preferably 1.2 million or less, and more preferably 900,000 or less. In addition, the weight average molecular weight (Mw) in this specification is a value converted from standard polystyrene measured by gel permeation chromatography (GPC). Since the above-mentioned weight average molecular weight (Mw) is within the above-mentioned range, the obtained adhesive becomes easy to exhibit the above-mentioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

(1-2) Crosslinking agent (B) The crosslinking agent (B) is triggered by heating or the like of the adhesive composition P containing the crosslinking agent (B) to generate the crosslinking of the active energy ray-curable polymer (A), thereby forming a three-dimensional grid structure. In this way, the cohesive force of the obtained adhesive is improved, and the adhesive force becomes higher.

The above-mentioned crosslinking agent (B) may be capable of reacting with the functional group of the active energy ray-curable polymer (A), for example, isocyanate-based crosslinking agents and epoxy-based crosslinking agents , Amine crosslinkers, melamine crosslinkers, aziridine crosslinkers, hydrazine crosslinkers, aldehyde crosslinkers, oxazoline crosslinkers, metal alkoxide crosslinkers, metals Chelate type crosslinking agent, metal salt type crosslinking agent, ammonium salt type crosslinking agent, etc. Here, when the active energy ray-curable polymer (A) includes a hydroxyl group-containing monomer as a structural monomer unit, an isocyanate-based crosslinking agent having excellent reactivity with the hydroxyl group is used as the crosslinking agent (B) Better. Moreover, a crosslinking agent (B) may be used individually by 1 type, and may be used in combination of 2 or more types.

The isocyanate-based crosslinking agent contains at least a polyisocyanate compound. Examples of the polyisocyanate compound include aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, and xylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, and isophorone diisocyanate. Alicyclic polyisocyanates such as isocyanate, hydrogenated diphenylmethane diisocyanate, etc., and its biuret body, isocyanurate body, and the above and ethylene glycol, propylene glycol, neopentyl glycol, trimethylol Adducts of reaction products of low molecular weight hydrogen-containing active compounds such as propane and castor oil. Among them, from the viewpoint of reactivity with a hydroxyl group, it is preferable to use an aliphatic isocyanate having hexamethylene diisocyanate, a trimethylolpropane-modified toluene diisocyanate, or the like.

Relative to 100 parts by mass of the active energy ray-curable polymer (A), the content of the crosslinking agent (B) in the adhesive composition P is preferably 0.01 parts by mass or more, particularly preferably 0.1 parts by mass or more, and It is more preferably 0.3 parts by mass or more. Furthermore, the content is preferably 10 parts by mass or less, preferably 5 parts by mass or less, particularly preferably 2 parts by mass or less, and more preferably 0.7 parts by mass or less. Since the content of the crosslinking agent (B) is within the above range, the cohesive force of the obtained adhesive becomes moderately high, especially the adhesive force at high temperature becomes higher, and it becomes easy to satisfy the aforementioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

(1-3) Photopolymerization initiator (C) In the case of using ultraviolet rays as the active energy ray for curing the active energy ray-curable adhesive, the adhesive composition P preferably contains a photopolymerization initiator (C). In this way, the polymerization curing time and the amount of light irradiation can be reduced.

Specific examples of the photopolymerization initiator (C) include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, and benzoin Methyl benzoate, benzoin dimethyl ketal, 2,4-diethyl thioxanthone, 1-hydroxycyclohexyl phenyl ketone, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, double Nitrogen diisobutyronitrile, phenyl, dibenzyl, diacetyl, β-chloroanthraquinone, (2,4,6-trimethylbenzyldiphenyl) phosphine oxide, 2-benzothiazole-N , N-diethyldithiocarbamate, oligo{2-hydroxy-2-methyl-1-[4-(1-propenyl)phenyl]acetone}, 2,2-dimethoxy -1,2-diphenylethane-1-one, 2-hydroxy-1-{4-[4-(4-(2-hydroxy-2-methyl-propanyl)-benzyl]benzene Yl]-2-methyl-propan-1-one, etc. The above-mentioned materials may be used alone or in combination of two or more kinds.

Relative to 100 parts by mass of the active energy ray-curable polymer (A), the content of the photopolymerization initiator (C) in the adhesive composition P is preferably 0.4 parts by mass or more, particularly preferably 0.8 parts by mass or more , And more preferably 1.2 parts by mass or more. On the other hand, this content is preferably 10 parts by mass or less, particularly preferably 6 parts by mass or less, and more preferably 4 parts by mass or less. Since the content of the photopolymerization initiator (C) is within the above range, the polymerization hardening time and the amount of light irradiation can be effectively reduced, and the resulting adhesive becomes easy to exhibit the aforementioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

(1-4) Various additives In the adhesive composition P, various additives commonly used in active energy ray-curable adhesives, such as silane coupling agents, ultraviolet absorbers, curing inhibitors, tackifiers, antioxidants, and light stabilizers, can be added as required. Agents, softeners, fillers, etc.

Examples of hardening inhibitors include acetylene such as acetylene alcohol, 2-propyn-1-ol, 2-methyl-3-butyn-2-ol, and 3-trimethylsilyloxypropyne. Compound, N,N,N',N'-tetramethylethylenediamine, N,N-dimethylethylenediamine, N,N-diethylethylenediamine, N,N-dibutylethylenediamine Amine, N,N-dibutyl-1,3-propanediamine, N,N-dimethyl-1,3-propanediamine, N,N,N',N'-tetraethylethylenediamine , N,N-Dibutyl-1,4-butanediamine, 2,2'-bipyridine and other amine compounds, and 1,2-diester compounds such as dimethyl malate. The above-mentioned materials may be used singly or in combination of two or more kinds.

With respect to 100 parts by mass of the active energy ray-curable polymer (A), the content of the curing inhibitor in the adhesive composition P is preferably 0.1 parts by mass or more, particularly preferably 1 part by mass or more, and 3 parts by mass More than one portion is better. Furthermore, the content is preferably 18 parts by mass or less, particularly preferably 12 parts by mass or less, and more preferably 6 parts by mass or less. Since the content of the hardening inhibitor is within the above range, the resulting adhesive tends to easily express the above-mentioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

As the silane coupling agent, an organosilicon compound having at least one alkoxysilyl group in the molecule and having good miscibility with the active energy ray-curable polymer (A) is preferred. In the case of using a glass substrate as a substrate for fixing a workpiece, the use of a silane coupling agent can make the resulting adhesive easily exhibit high adhesion to the substrate. As the adhesion to the substrate improves, it becomes easier to peel the workpiece from the adhesive layer in a state where the adhesive layer and the substrate are in close contact.

Furthermore, as the silane coupling agent, a silane coupling agent having a group selected from vinyl group, epoxy group, styryl group, acryl group, methacryl group, amino group, urea group, isocyanate group, isocyanurate group, and mercapto group can be used. , A silane coupling agent with at least one functional group among methyl group and thiol group is preferred. Among them, from the viewpoint of improving adhesion, it is preferable to use a silane coupling agent containing at least one of an epoxy group and a mercapto group, and it is particularly preferable to use a mercapto group-containing silane coupling agent.

As described above, in the case where the silane coupling agent contains a mercapto group, the silane coupling agent becomes able to react well with the crosslinking agent (B). In particular, when the crosslinking agent (B) is an isocyanate-based crosslinking agent, the mercapto group in the silane coupling agent easily reacts with the isocyanate group in the isocyanate-based crosslinking agent. On the other hand, as described above, the crosslinking agent (B) also has a function of crosslinking the active energy ray-curable polymer (A). Therefore, in the formed adhesive, the active energy ray-curable polymer (A) is cross-linked by the cross-linking agent (B), and the silane coupling agent is combined with the cross-linking agent (B) through the sulfhydryl group to form Three-dimensional grid structure. In this adhesive, the alkoxysilyl group of the silane coupling agent has an appropriate distance from the active energy ray-curable polymer (A) (especially when the crosslinking agent (B) is an isocyanate crosslinking agent In the case of the distance between the plural isocyanate groups), it can be inferred that it is in the form of dangling bonds on the active energy ray-curable polymer (A). Since the alkoxysilyl group exists at an appropriate distance from the (crosslinked) active energy ray-curable polymer (A) as described above, it can exhibit an excellent coupling effect. As a result, even in the obtained When the adhesive is heat-treated, it becomes easy to exhibit the desired adhesiveness. As a result, the adhesive sheet according to this embodiment has more excellent handling properties.

Furthermore, when the silane coupling agent contains the above-mentioned functional groups, the number of functional groups in one molecule of the silane coupling agent may be 1 (monofunctional type) or plural (multifunctional type), and From the viewpoint of improving the adhesion of the adhesive layer to the substrate, a polyfunctional type is preferred.

Examples of such silane coupling agents include polymerizable unsaturated group-containing silicon compounds such as vinyl trimethoxysilane, vinyl triethoxysilane, and methacryloxypropyl trimethoxysilane. , 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and other silicon compounds with epoxy structure, 3-mercaptopropyltrimethoxysilane Silane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyldimethoxymethylsilane and other mercapto group-containing silicon compounds, 3-aminopropyltrimethoxysilane, N-(2-amino Ethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane and other amino-containing silicon compounds, 3-chloropropyltrimethyl Oxysilane, 3-isocyanatopropyltriethoxysilane, or at least one of the above and methyltriethoxysilane, ethyltriethoxysilane, methyltrimethoxysilane, ethyl Condensates of alkyl-containing silicon compounds such as trimethoxysilane. The above-mentioned materials may be used singly or in combination of two or more kinds.

Relative to 100 parts by mass of the active energy ray-curable polymer (A), the content of the silane coupling agent in the adhesive composition P is preferably 0.01 parts by mass or more, particularly preferably 0.05 parts by mass or more, and 0.10 parts by mass More than one portion is better. Furthermore, this content is preferably 1.0 part by mass or less, particularly preferably 0.5 part by mass or less, and more preferably 0.3 part by mass or less. Since the content of the hardening inhibitor is within the above range, the resulting adhesive tends to easily express the above-mentioned adhesive properties. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.).

Examples of ultraviolet absorbers include benzotriazoles, benzophenones, benzoates, benzoxazinones, triazines, phenyl salicylate, and cyanoacrylates. , Nickel compound salts and other compounds. The above-mentioned materials may be used singly or in combination of two or more kinds.

Relative to 100 parts by mass of the active energy ray-curable polymer (A), the content of the ultraviolet absorber in the adhesive composition P is preferably 1 part by mass or more, particularly preferably 2 parts by mass or more, and 3 parts by mass More than one portion is better. Furthermore, the content is preferably 15 parts by mass or less, particularly preferably 12 parts by mass or less, and more preferably 8 parts by mass or less.

(2) Manufacturing of adhesive composition P The active energy ray curable polymer (A) can be produced by combining the obtained active energy ray curable polymer (A), the crosslinking agent (B), and the photopolymerization initiator (C) as required. ) And other additives to produce the adhesive composition P. In addition, a diluting solvent may be added to the adhesive composition P as required and mixed thoroughly to obtain the adhesive composition P (coating solution) diluted with the solvent.

In addition, if any of the above-mentioned components is used in a solid form, or when precipitation occurs when mixed with other components in an undiluted state, the component may be dissolved or diluted separately first. It is mixed with other ingredients only after it is in the diluting solvent.

Examples of the above-mentioned dilution solvent include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as dichloromethane and ethyl chloride, methanol, ethanol, and propylene. Alcohols such as alcohol, butanol, 1-methoxy-2-propanol, acetone, methyl ethyl ketone, 2-pentanone, isophorone (Isophorone), ketones such as cyclohexanone, ethyl acetate, butyl acetate And other esters, cellosolves such as ethyl cellosolve (cellosolve), etc.

The concentration/viscosity of the coating solution prepared in the above-mentioned manner is not particularly limited as long as it is within a coating (coating) range, and can be appropriately selected according to the situation. For example, the concentration of the adhesive composition P can be diluted to 10-60% by mass. In addition, when obtaining the coating solution, the addition of a dilution solvent and the like is not essential, as long as the adhesive composition P has a viscosity etc. that can be applied, and the dilution solvent may not be added.

(3) Formation of adhesive layer The adhesive layer 11 can be formed by crosslinking the adhesive composition P after application. The crosslinking of the adhesive composition P is preferably performed by heat treatment. In addition, this heat treatment can also be used as a drying treatment after the adhesive composition P is applied.

The heating temperature of the heat treatment is preferably 50 to 150°C, and particularly preferably 70 to 120°C. Furthermore, the heating time is preferably 10 seconds to 10 minutes, and particularly preferably 50 seconds to 2 minutes. Furthermore, it is also preferable to set the curing period at normal temperature (for example, 23° C., 50% RH) for about 1 to 2 weeks after the heat treatment.

By the above-mentioned heat treatment (and curing), the active energy ray-curable polymer (A) can be cross-linked satisfactorily through the cross-linking agent (B).

(4) The thickness of the adhesive layer The lower limit of the thickness (value measured according to JIS K7130) of the adhesive layer 11 of the adhesive sheet 1 according to the present embodiment is preferably 5 μm or more, particularly preferably 10 μm or more, and more preferably 15 μm or more. When the lower limit of the thickness of the adhesive layer 11 is as described above, the adhesive force becomes more excellent. Furthermore, the upper limit of the thickness of the adhesive layer 11 is preferably 50 μm or less, particularly preferably 40 μm or less, more preferably 30 μm or less, and most preferably 25 μm or less. When the upper limit of the thickness of the adhesive layer 11 is as described above, it becomes easy to express the aforementioned adhesive properties, and in particular, the easy peelability becomes more excellent. Furthermore, it has excellent durability (acid resistance, alkali resistance, foam resistance, etc.). In addition, the adhesive layer 11 may be formed as a single layer, or may be formed by stacking a plurality of layers.

1-2. Peeling sheet The peeling sheets 12a and 12b protect the adhesive layer 11 before using the adhesive sheet 1, and are peeled off when the adhesive sheet 1 (adhesive layer 11) is used. In the adhesive sheet 1 according to the present embodiment, one or both of the release sheets 12a and 12b are not absolutely necessary.

As the release sheets 12a and 12b, for example, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film, and a polyvinyl chloride film can be used. Ethylene phthalate film, polyethylene naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate film, ionomer resin film, ethylene/(meth)acrylic acid Copolymer film, ethylene/(meth)acrylate copolymer film, polystyrene film, polycarbonate film, polyimide film, fluororesin film, etc. Furthermore, crosslinked films of the above-mentioned materials can also be used. In addition, a laminated film of the above-mentioned materials can also be used.

The peeling surfaces of the peeling sheets 12a and 12b (especially the surfaces in contact with the adhesive layer 11) are preferably peeled off. Examples of the release agent used in the release treatment include alkyd, silicone, fluorine, unsaturated polyester, polyolefin, and wax release agents. In addition, among the release sheets 12a and 12b, it is preferable that one of the release sheets is a heavy release type with a large release force and the other release sheet is a light release type with a small release force.

The thickness of the release sheets 12a and 12b is not particularly limited, but is usually about 20 to 150 μm.

2. Manufacture of Adhesive Sheet As a manufacturing example of the adhesive sheet 1, the case where the said adhesive composition P is used is demonstrated. After applying the coating liquid of the adhesive composition P on the peeling surface of one peeling sheet 12a (or 12b), and performing heat treatment to thermally crosslink the adhesive composition P to form a coating layer, the other sheet is peeled off The peeling surface of the sheet 12b (or 12a) is superimposed on this coating layer. In the case where a curing period is required, the adhesive layer 11 is formed by placing the coating layer for a period of curing period, and in the case where a curing period is not required, the coating layer directly serves as the adhesive layer 11. In the above manner, the above-mentioned adhesive sheet 1 can be obtained. The conditions for heat treatment and curing are as described above.

As a coating method of the coating liquid of the adhesive composition P, for example, a bar coating method, a knife coating method, a roll coating method, or a blade coating method can be used. Coating method, die coating method, gravure coating method, etc.

3. The use of adhesive sheet As described in the foregoing, the adhesive sheet 1 according to the present embodiment is suitable for fixing in the process of processing, laminating, and inspecting devices such as optical components and electronic components as workpieces (preferably flexible devices). Substrate. In addition, after the above-mentioned process is completed, the workpiece is peeled from the substrate.

FIG. 2 shows a cross-sectional view of the laminated body 4 showing the state of use of the adhesive sheet 1. The laminated body 4 according to this embodiment is formed by laminating the flexible device 2 as a work, the adhesive layer 11 of the adhesive sheet 1, and the substrate 3 in this order. In such a laminated body 4, the flexible device 2 is firmly fixed to the substrate 3 through the adhesive layer 11, so this process can be performed smoothly without problems.

The above-mentioned process is suitably a process that includes heating the workpiece or heating the workpiece together. Examples of such heat treatment include a metal vapor deposition process, a resin hardening process such as a sealing resin, and an annealing process. According to the adhesive sheet 1 and the laminated body 4 of this embodiment, since the adhesive layer 11 that satisfies the aforementioned physical properties is provided, even if the heat treatment is performed, the adhesion to the workpiece can be reduced well by subsequent irradiation of active energy rays. In this way, the workpiece can be easily peeled from the adhesive layer 11.

The above-mentioned heat treatment can adopt the same conditions as the general heat treatment. For example, the heating temperature is preferably 40°C or higher, particularly preferably 80°C or higher, and more preferably 120°C or higher. Furthermore, the heating temperature is preferably 200°C or less, particularly preferably 180°C or less, and more preferably 160°C or less. Furthermore, the heating time is preferably 5 minutes or more, particularly preferably 10 minutes or more, and more preferably 20 minutes or more. Furthermore, the heating time is preferably 60 minutes or less, particularly preferably 50 minutes or less, and more preferably 40 minutes or less.

After the above-mentioned process is completed, the adhesive layer 11 (or the flexible device 2/substrate 3) is irradiated with active energy rays to harden the adhesive layer 11, thereby reducing the adhesion to the workpiece. In this way, the workpiece can be easily peeled off from the adhesive layer 11.

As such active energy rays for peeling the workpiece, ultraviolet rays, electron beams, etc. are generally used, and ultraviolet rays, which are easy to handle, are particularly preferred. In the case of using ultraviolet rays, high-pressure mercury lamps, fusion lamps, xenon lamps, etc. can be used for irradiation. Furthermore, the irradiation conditions are preferably 50 mW/cm ² or more and 1000 mW/cm ² or less. Furthermore, the integrated luminosity of the ultraviolet rays is ^{preferably 1500 mJ/cm 2} or more, and particularly preferably 2000 mJ/cm ² or more. Furthermore, the integrated luminosity of the ultraviolet rays is preferably 5000 mJ/cm ² or less, and particularly preferably 3000 mJ/cm ² or less.

The embodiments described above are described in order to facilitate the understanding of the present invention, and are not described in order to limit the present invention. Therefore, it means that each requirement disclosed in the above-mentioned embodiment also includes all design changes and equivalents falling within the technical scope of the present invention.

For example, one or both of the release sheets 12a and 12b in the adhesive sheet 1 may be omitted. [Example]

Hereinafter, the present invention will be explained more specifically through examples and the like, but the scope of the present invention is not limited to these examples and the like.

[Example 1] 1. Preparation of adhesive composition Acrylic copolymer obtained by copolymerizing 50 parts by mass of 2-ethylhexyl acrylate, 10 parts by mass of n-butyl acrylate, 10 parts by mass of acrylomorpholine, and 30 parts by mass of 4-hydroxybutyl acrylate , It reacts with methyl isobutylene oxyethyl isocyanate (MOI) whose molar number of 4-hydroxybutyl acrylate relative to the acrylic copolymer is 90 mol% to obtain an active energy ray-curable polymer. The weight average molecular weight (Mw) of this active energy ray-curable polymer is 700,000 measured by the method described later.

100 parts by mass of the obtained active energy ray-curable polymer (calculated as solid content, the same applies hereinafter) and 0.75 parts by mass of aliphatic isocyanate with hexamethylene diisocyanate as a crosslinking agent (produced by Nippon Polyurethane Industry Co., Ltd. Manufactured, the product name is "Coronate HX"), 5 parts by mass of hardening inhibitor (manufactured by Toyo Chemical Company, the product name is "BXX5638"), and 3.0 parts by mass of 2-hydroxy-1 as a photopolymerization initiator -{4-[4-(2-Hydroxy-2-methyl-propanyl)-benzyl]phenyl}-2-methyl-propane-1-one (manufactured by BASF, the product name is " Irgacure 127”) is mixed in a solvent to obtain an adhesive composition.

2. Manufacture of Adhesive Sheet The obtained coating solution of the adhesive composition was applied using a knife coater to the weight obtained by peeling off one side of the polyethylene terephthalate film using a silicone-based release agent. The peel-off processing surface of the peel-off type peeling sheet (manufactured by Lintec, the product name is "SP-PET751130"). Next, the coating layer was heated at 90°C for 1 minute to form the coating layer.

After that, the coating layer on the heavy release release sheet obtained above and the light release type obtained by peeling off one side of the polyethylene terephthalate film using a silicone-based release agent The peeling sheet (manufactured by Lindeco, the product name is "SP-PET 382120"), the lightly peeling peeling sheet is attached to each other in such a way that the peeling surface of the peeling sheet is in contact with the coating layer, and the temperature is at 23°C and 50°C. After curing for 7 days under the condition of %RH, an adhesive sheet composed of a heavy peeling release sheet/adhesive layer (thickness: 10μm)/light peeling peeling sheet was produced. In addition, the thickness of the adhesive layer is a value measured in accordance with JIS K7130 using a constant pressure thickness gauge (manufactured by TECLOCK, product name "PG-02").

Here, the aforementioned weight average molecular weight (Mw) is a weight average molecular weight in terms of polystyrene measured (GPC measurement) using gel permeation chromatography (GPC) under the following conditions. <Measurement conditions> ‧GPC measuring device: manufactured by Tosoh, HLC-8320 ‧GPC string (pass in the following order): manufactured by Tosoh TSK gel super H-H TSK gel super HM-H TSK gel super H2000 ‧Measuring solvent: tetrahydrofuran (tetrahydrofuran) ‧Measuring temperature: 40℃

[Examples 2 to 12, Comparative Examples 2 to 3] The type and ratio of monomers constituting the acrylic copolymer, the amount of MOI used, the weight average molecular weight of the active energy ray curable polymer, the type and amount of crosslinking agent, and the type and amount of photopolymerization initiator , The type and amount of silane coupling agent, and the thickness of the adhesive layer are changed as shown in Table 1, and the rest is the same as in Example 1 to make an adhesive sheet.

[Comparative Example 1] By copolymerizing 50 parts by mass of 2-ethylhexyl acrylate, 10 parts by mass of n-butyl acrylate, 10 parts by mass of acrylomorpholine, and 30 parts by mass of 4-hydroxybutyl acrylate to obtain acrylic Copolymer. The weight average molecular weight (Mw) of this acrylic copolymer is 650,000 measured by the method described later. In addition, in the column of "weight average molecular weight of active energy ray-curable polymer" in Table 1, the above-mentioned measurement results for the acrylic copolymer are described for Comparative Example 1.

100 parts by mass of the obtained acrylic copolymer, 0.75 parts by mass of aliphatic isocyanate with hexamethylene diisocyanate as a crosslinking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., product name "Coronate HX"), 5 Parts by mass of hardening inhibitor (manufactured by Toyo Chemical Company, product name "BXX5638"), 3.0 parts by mass of 2-hydroxy-1-{4-[4-(2-hydroxy-2) as a photopolymerization initiator -Methyl-propanyl)-benzyl]phenyl}-2-methyl-propan-1-one (manufactured by BASF, product name "Irgacure 127") is mixed in a solvent to obtain adhesiveness combination.

Except that the adhesive composition obtained as described above was used, the adhesive sheet was manufactured in the same manner as in Example 1.

[Test Example 1] (Measurement of Gel Fraction) The adhesive sheets obtained in the examples and comparative examples were cut into a size of 80mm×80mm, and the adhesive layer was wrapped in a polyester mesh (mesh size of 200), and the mass was measured with a precision balance. And by deducting the quality of the polyester net itself, and then calculate the quality of only the adhesive. The mass at this time is set to M1.

Next, the adhesive coated in the polyester net was immersed in ethyl acetate at room temperature (23° C.) for 24 hours. After that, the adhesive was taken out, air-dried for 24 hours in an environment with a temperature of 23°C and a relative humidity of 50%, and further dried in an oven at 80°C for 12 hours. After drying, weigh its mass with a precision balance, and by subtracting the mass of the polyester net itself, the mass of only the adhesive is calculated. The mass at this time is set to M2.

_{Regarding the masses M1 and M2 obtained in the above manner, the gel fraction G 1} (%) of the adhesive layer in the state before the active energy ray is irradiated is calculated by the algorithm of (M2/M1)×100. The results are shown in Table 2.

In addition, the adhesive layer of the adhesive sheet obtained in the Example and the comparative example was irradiated with ultraviolet rays through the heavy peelable release sheet under the following ultraviolet irradiation conditions. With respect to the adhesive layer irradiated with ultraviolet rays, the gel fraction was measured in the same manner as described above, and the gel fraction of the adhesive layer after the active energy ray was irradiated was G ₂ (%). The results are shown in Table 2. <Ultraviolet radiation conditions> ^{‧Using a high-pressure mercury lamp ‧Illuminance is 200 mW/cm 2} , integrated luminosity is 2000 mJ/cm ² ‧UV illuminance and light meter use the product "UVPF-A1" manufactured by Eye Graphics

Furthermore, the ratio (G ₂ /G ₁ ) of the gel fraction G ₂ (%) to the gel fraction G _{1 (%) measured as described above was calculated.} The results are also shown in Table 2.

[Test Example 2] (Measurement of Storage Elastic Modulus) The release sheet was peeled from the adhesive sheets obtained in the examples and comparative examples, and a plurality of layers were laminated to form an adhesive layer having a thickness of 3 mm. A cylinder with a diameter of 8 mm (height of 3 mm) was punched out from the laminate of the obtained adhesive layer, and this was used as a sample.

According to JIS K7244-6:1999, using a viscoelasticity measuring device (manufactured by Physica, the product name is "MCR300"), the torsional shear method is used to measure the storage elastic modulus of the above sample under the following conditions (MPa). The results are shown in Table 2 in the storage elastic modulus G′ ₁ in the state before the active energy ray is irradiated. Measuring frequency: 1 Hz Measuring temperature: 23℃

Furthermore, under the aforementioned ultraviolet irradiation conditions, after irradiating the sample obtained in the same manner as described above with ultraviolet rays, the storage elastic modulus (MPa) was measured in the same manner as described above. The results are shown in Table 2 as the storage elastic modulus G′ ₂ after irradiation with active energy rays.

Further calculates a storage elastic modulus G _'2 (MPa) is measured as described above with respect to the storage elastic modulus G' ₂ (MPa) ratio _{(G '2 / G' 1} ). The results are also shown in Table 2.

[Test Example 3] (Measurement of Adhesion) The lightly peelable release sheet was peeled off from the adhesive sheets obtained in the examples and comparative examples, and the exposed adhesive layer was bonded to polyethylene terephthalate having an easy-adhesive layer as a backing material (PET) film (manufactured by Toyobo, product name "PET A4300", thickness: 25μm) easy-adhesive layer, and then a layered body of heavy peeling release sheet/adhesive layer/PET film. The obtained laminate was cut into a width of 25 mm and a length of 100 mm, and this was used as a sample.

In an environment of 23°C and 50%RH, the heavy-peelable release sheet was peeled from the above sample, and in an environment of 23°C and 50%RH, a 2kg rubber roller was used to apply the cycloolefin as the resin film. The exposed adhesive layer is attached to one side of a polymer (COP) film (thickness: 40μm). After that, under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180 degrees, the adhesive layer was peeled from the resin film, and the adhesive force (N/25mm) at this time was measured. In addition, the measurement was performed in accordance with the standard of JIS Z0237:2009 except for the conditions described here. The adhesive force thus obtained is defined as the adhesive force F ₀ (N/25mm) before the active energy ray is irradiated. The results are shown in Table 2.

Furthermore, the sample produced in the same manner as described above was placed under high temperature conditions of 150° C. and 50% RH for 30 minutes for heating treatment. After that, put it back to room temperature until the temperature of the sample drops to room temperature. The adhesive force of this sample was measured in the same way as above, and it was taken as the adhesive force F ₁ (N/25mm) after the heat treatment. The results are shown in Table 2.

Furthermore, the sample produced in the same manner as described above was placed under a high temperature condition of 150° C. and 50% RH for 30 minutes for heating treatment, and then returned to a room temperature environment. Under the aforementioned ultraviolet irradiation conditions, the adhesive layer of the sample whose temperature has returned to room temperature is irradiated with ultraviolet rays through the heavy peeling release sheet. The adhesive force of the adhesive layer irradiated with ultraviolet rays was measured in the same manner as described above, and this was used as the adhesive force F ₂ (N/25 mm) after heat treatment and active energy ray irradiation. The results are shown in Table 2.

Further each adhesive force F ₁ (N / 25mm) calculating the ratio as described above on the measured initial adhesive force F ₀ (N / 25mm) to (F ₁ / F _0), the adhesive force F ₂ (N / 25mm) relative The ratio of the initial adhesion force F ₀ (N/25mm) (F ₂ /F ₀ ), and _{the ratio of the adhesion force F 2} (N/25mm) to the adhesion force F ₁ (N/25mm) (F ₂ /F ₁ ). These results are shown in Table 2.

[Test Example 4] (Process Evaluation) A cycloolefin polymer (COP) film (thickness: 40 μm) as a workpiece was prepared. The lightly peelable release sheet was peeled from the adhesive sheets obtained in the examples and comparative examples, and the exposed adhesive layer was bonded to one side of the above-mentioned workpiece to obtain a heavy peelable release sheet/adhesive layer/COP The laminated body of the film. The obtained laminate was cut into a width of 2.5 cm and a length of 10 cm (the area of the surface of the adhesive layer in contact with the workpiece: 25 mm ² ).

In an environment of 23°C and 50% RH, the heavy-peelable release sheet was peeled from the laminate, and the exposed adhesive layer was attached to soda lime glass (manufactured by Nippon Plate Glass Co., Ltd.), using Kurihara Manufacturing Co., Ltd. The manufactured autoclave was pressurized at 0.5 MPa and 50°C for 20 minutes, and this was used as a sample. The obtained sample was placed under high temperature conditions of 150° C. and 50% RH for 30 minutes for heat treatment. For the above heat-treated samples, the state of floating and peeling at the interface between the COP film and the adhesive layer, and the state of the COP film fixed on the adhesive layer were confirmed, and the process evaluation was performed according to the following criteria. The results are shown in Table 2 Process Evaluation A. ⊚: No floating/peeling occurs at the interface, and the COP film is well fixed to the adhesive layer. ○: A slight floating/peeling of the interface was observed only at the edge portion of the laminate, and the COP film was well fixed to the adhesive layer. △: Although the COP film is fixed on the adhesive layer, floating/peeling at the interface is observed. ╳: It is found that the interface is floating/peeling, and the COP film cannot be fixed on the adhesive layer.

Next, with respect to the laminate obtained in the above process evaluation A with "⊚", "◯" or "△", under the aforementioned ultraviolet irradiation conditions, ultraviolet rays are irradiated from the surface on the side of the COP film. Next, the COP film was peeled from the adhesive layer, and the state at this time was evaluated according to the following criteria. The results are shown in Table 2 Process Evaluation B. ⊚: The COP film can be easily peeled off with almost no peeling force. ○: Although a peeling force is required, the COP film can be peeled off. ╳: The COP film cannot be peeled off.

[Test Example 5] (Evaluation of acid resistance and alkali resistance) The adhesive layer of the adhesive sheet obtained in the examples and comparative examples was sandwiched between a cycloolefin polymer (COP) film (thickness: 40 μm) and soda lime glass (manufactured by Nippon Plate Glass Co., Ltd.), To make a laminated body.

The laminate was immersed in an aqueous sulfuric acid solution (sulfuric acid concentration: 0.1N) heated to 50° C. for 30 minutes. After that, the layered body was taken out from the sulfuric acid aqueous solution, and whether the adhesive layer had bubbles, floating, or peeling was visually confirmed, and the acid resistance was evaluated based on the following criteria. The results are shown in Table 2. ○: No bubbles, floating, and peeling occurred at all. ╳: It is confirmed that there are bubbles, floating or peeling.

Furthermore, the layered body manufactured in the same manner as described above was immersed in an aqueous sodium hydroxide solution (sodium hydroxide concentration: 0.1 N) heated to 50° C. for 30 minutes. After that, the laminate was taken out from the sodium hydroxide aqueous solution, and whether the adhesive layer had bubbles, floats, or peeling was visually confirmed, and the alkali resistance was evaluated based on the same criteria as the above. The results are shown in Table 2.

[Test Example 6] (Evaluation of Blister Resistance) The adhesive layers of the adhesive sheets obtained in the examples and comparative examples were sandwiched on one side of a polyethylene terephthalate film (made of transparent conductive film made of indium tin oxide (ITO)). ITO-PET film, thickness: 125μm) made by Oike Kogyo Co., Ltd., a transparent conductive film, and soda lime glass (manufactured by Nippon Plate Glass Co., Ltd.) to obtain a laminate.

After autoclaving the obtained layered body under the conditions of 50°C and 0.5 MPa for 30 minutes, it was allowed to stand for 15 hours under the conditions of normal pressure, 23°C, and 50% RH. Next, it was stored for 72 hours under durable conditions of 85°C and 85% RH. Then, visually confirm whether the adhesive layer has bubbles, float, or peel, and evaluate the blistering resistance based on the following criteria. The results are shown in Table 2. ◎: There is no air bubbles, floating, and peeling at all. ○: A few bubbles, floating, or peeling are found only in the edge portion of the laminate. △: 5 bubbles, floating, or peeling occurred in the entire laminate. ╳: There are more than 6 bubbles, floating or peeling in the whole laminate.

Furthermore, the adhesive layers of the adhesive sheets obtained in the examples and comparative examples were sandwiched between a cycloolefin polymer (COP) film (thickness: 40 μm) and soda lime glass (manufactured by Nippon Plate Glass Co., Ltd.) In the meantime, a layered body was produced, and for this layered body, the blistering resistance was evaluated in the same manner as described above. The results are shown in Table 2.

Here, the details of the abbreviations and the like described in Table 1 are as follows. [Active energy ray-curable polymer] 2EHA: 2-ethylhexyl acrylate BA: n-butyl acrylate ACMO: N-acryloylmorpholine MA: methyl acrylate 4HBA: 4-hydroxybutyl acrylate MOI: Methacryloxyethyl isocyanate [Crosslinking agent] Coronate HX: Aliphatic isocyanate with hexamethylene diisocyanate (manufactured by Japan Polyurethane Industry Co., Ltd., product name "Coronate HX") BHS8515: Trimethylolpropane modified toluene diisocyanate (manufactured by Toyo Chemical Co., Ltd., product name "BHS8515") [Photopolymerization initiator] Irgacure 127: 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propanyl)-benzyl]phenyl}-2-methyl-propane-1-one (from BASF Manufactured by the company, the product name is "Irgacure 127") Omnirad 500: a mixture of 1-hydroxycyclohexyl phenyl ketone and benzophenone with a mass ratio of 1:1 (manufactured by BASF, product name "Omnirad 500") [Silane Coupling Agent] X-12-1156: Silane coupling agent containing sulfhydryl group (manufactured by Shin-Etsu Chemical Co., Ltd., product name is "X-12-1156", multifunctional silane coupling agent) KBM-403: Epoxy-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., product name is "KBM-403", monofunctional silane coupling agent)

[Table 1]

[Table 2]

From the results of the initial adhesion force F ₀ and the adhesion force F ₁ in Table 2, it is clear that the adhesive sheet manufactured in the embodiment can exhibit excellent adhesion to the workpiece in the state before the ultraviolet ray is irradiated. In particular, the adhesive sheets manufactured in the examples also exhibited good adhesive force F ₁ after heat treatment. From the result of process evaluation A, it is clear that the adhesive sheet according to the embodiment exhibiting this characteristic can also hold the workpiece well after the predetermined heat treatment.

On the other hand, _{it is clear from the results of the adhesive force F 2} that the adhesive sheet manufactured in the example has a significant decrease in adhesive force to the workpiece due to ultraviolet radiation. From the result of process evaluation B, it is clear that the adhesive sheet according to the embodiment exhibiting such characteristics can easily peel off the workpiece by irradiating predetermined ultraviolet rays. [Industrial Utilization]

The adhesive sheet according to the present invention is suitable for process adhesive sheets used in processes such as processing, lamination, and inspection of flexible devices, and is particularly suitable for process adhesive sheets used in processes including heat treatment sheet.

1: Adhesive sheet 11: Adhesive layer 12a, 12b: peeling sheet 2: Workpiece (flexible device) 3: substrate 4: Layered body

[Fig. 1] is a cross-sectional view of an adhesive sheet according to an embodiment of the present invention. Fig. 2 is a cross-sectional view of a laminate according to an embodiment of the present invention.

1: Adhesive sheet

11: Adhesive layer

12a, 12b: peeling sheet

Claims (10)

An adhesive sheet, which is an adhesive sheet comprising at least an adhesive layer, wherein the adhesive sheet is used for fixing a workpiece to a substrate through the adhesive layer during a manufacturing process and peeling the workpiece from the adhesive layer after the process is completed , And the adhesive layer is composed of an active energy ray curable adhesive, and the initial adhesive force of the adhesive sheet is set to F ₀ , and the adhesive will be heated at 150° C. for 30 minutes and then further irradiated with active energy rays. When the adhesive force of the adhesive sheet is F ₂ , the ratio of the aforementioned adhesive force F ₂ to the initial adhesive force F _{0 (F 2} /F ₀ ) is 0.3 or less. The adhesive sheet according to claim 1, wherein after the adhesive layer is irradiated with active energy rays, the storage elastic modulus of the adhesive layer at 23° C. is 0.1 MPa or more and 2 MPa or less. The adhesive sheet according to claim 1, wherein the active energy ray-curable adhesive includes a silane coupling agent. The adhesive sheet according to claim 1, wherein the aforementioned initial adhesive force F ₀ is 0.5N/25mm or more and 80N/25mm or less. The adhesive sheet according to claim 1, wherein the adhesive force F ₁ of the adhesive sheet after heating at 150° C. for 30 minutes is 0.5 N/25 mm or more and 80 N/25 mm or less. The adhesive sheet according to claim 1, wherein the aforementioned initial adhesive force F ₀ is 0.01N/25mm or more and 8N/25mm or less. The adhesive sheet according to claim 1, wherein the aforementioned workpiece is a flexible device. The adhesive sheet according to claim 1, wherein the aforementioned use includes heating of the aforementioned workpiece fixed on the aforementioned substrate. The adhesive sheet according to claim 1, wherein the adhesive sheet includes two release sheets, and the adhesive layer is sandwiched between the release sheets and contacts the release surfaces of the two release sheets. A laminated body formed by laminating a flexible device, the aforementioned adhesive layer of the adhesive sheet according to any one of claims 1 to 9, and a substrate in this order.

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