TWI816796B - Manufacturing method of hardened sealing body - Google Patents

Abstract

A method of manufacturing a hardened sealing body, which uses a base material (Y) having an expandable base material layer (Y1) containing expandable particles and a non-expandable base material layer (Y2), and a first adhesive layer ( X1) and the adhesive sheet of the second adhesive layer (X2), and has the following steps (1)~(3): ・Step (1): The step of attaching the adhesive surface of the first adhesive layer (X1) to a hard support and placing the sealing object on a part of the adhesive surface of the second adhesive layer (X2). ・Step (2): The step of covering the adhesion surface between the aforementioned sealing object and the second adhesive layer (X2) with a sealing material, and hardening the sealing material to obtain a hardened sealing body. ・Step (3): The step of expanding the aforementioned expandable particles and separating them at the interface P between the aforementioned hard support and the first adhesive layer (X1).

Description

Manufacturing method of hardened sealing body

The present invention relates to a method for manufacturing a hardened sealing body.

Adhesive sheets are not only used to semi-permanently fix components, but are also used for temporary fixing to temporarily fix the target components when processing or inspecting building materials, interior materials, electronic parts, etc. For such adhesive sheets used for temporary fixation, it is required to have both adhesion during use and peelability after use.

For example, Patent Document 1 discloses a heat-releasable adhesive sheet for temporarily fixing electronic components when cutting off, in which a thermally expandable adhesive layer containing thermally expandable microspheres is provided on at least one side of a base material. In this heat-peelable adhesive sheet, the maximum particle size of the heat-expandable microspheres is adjusted relative to the thickness of the heat-expandable adhesive layer, and the average center line thickness of the surface of the heat-expandable adhesive layer before heating is adjusted to 0.4 μm or less. Patent Document 1 describes that this heat-releasable adhesive sheet can fully ensure the adhesion area with the adherend when cutting electronic parts, so it can exhibit adhesion that can prevent bonding defects such as chip scattering. , if heated after use to expand the thermally expandable microspheres, the contact area with the adherend can be reduced and the adhesive can be easily peeled off. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent No. 3594853

[Problem to be solved by the invention]

In recent years, the miniaturization, thinning, and high-density of electronic equipment have been progressed. Semiconductor devices mounted in electronic equipment are also required to be miniaturized, thin, and high-density. As a semiconductor packaging technology that can meet such requirements, FOWLP (Fan out Wafer Level Package) is attracting attention. FOWLP is to provide a rewiring layer on the surface of the semiconductor chip side of a hardened sealing body that seals a plurality of semiconductor wafers arranged at specific intervals with a sealing material, and through the rewiring layer, the solder balls and the semiconductor chip are connected A semiconductor package that is electrically connected. Since FOWLP can fan out the terminals as solder balls to the outside of the semiconductor chip, it can also be used in applications where the number of terminals is large compared to the area of the semiconductor chip.

Generally speaking, FOWLP is achieved by placing the circuit surface of the semiconductor wafer on an adhesive sheet, filling the periphery of the semiconductor wafer with a fluid sealing resin heated to about 100°C, and heating it to form a The step of sealing a layer of sealing resin, or laminating a sealing resin film on a semiconductor chip, and heating the laminate, and removing the adhesive sheet to form a redistribution layer and solder balls on the surface of the exposed semiconductor chip side. Made in steps. In the sealing step of the above-mentioned FOWLP manufacturing method, it may also be considered to use a heat-releasable adhesive sheet in which a heat-expandable adhesive layer containing heat-expandable microspheres is provided on a base material as described in Patent Document 1.

However, since the heat-expandable adhesive layer of the heat-peelable adhesive sheet described in Patent Document 1 contains heat-expandable microspheres, it requires more processing or processing such as sealing than an adhesive layer that does not contain heat-expandable microspheres. Reduced adhesion during inspection is a concern. For example, the reduction in adhesion during the sealing step is due to the positional shift of the semiconductor chip placed on the adhesive layer, or the sealing resin invades the interface between the semiconductor chip and the adhesive sheet, causing the resin to adhere to the circuit surface of the semiconductor chip. The main causes of harm. In particular, when thermally expandable microspheres are expanded, the elastic modulus of the thermally expandable adhesive layer is generally adjusted to a low level, making the surface prone to unevenness. However, when placed on the surface of a thermally expandable adhesive layer with a low elastic modulus Semiconductor wafers are prone to positional deviation during the sealing step.

The occurrence of positional deviation of the semiconductor wafer and the adhesion of the sealing resin to the circuit surface of the semiconductor wafer are factors that reduce the yield in the manufacturing of semiconductor devices. Such problems may also occur in sealing objects other than semiconductor chips. Therefore, it is possible to obtain a cured sealing body that can suppress the harmful effects of positional deviation of the sealing object such as the semiconductor chip, which may occur when the cured sealing body is obtained, or the adhesion of the sealing resin to the exposed surface of the sealing object such as the circuit surface of the semiconductor chip. Manufacturing methods are subject to demand.

In addition, in the manufacturing of FOWLP, the support and the semiconductor wafer are generally fixed through a double-sided adhesive sheet having an adhesive layer on both sides of the base material. For example, the heat-releasable adhesive sheet described in Patent Document 1 is a double-sided adhesive sheet in which a thermally expandable adhesive layer and an adhesive layer are provided on both sides of a base material. A semiconductor wafer is placed on the thermally expandable adhesive layer side, and the adhesive layer is The side system is attached to the support body, and various processing such as sealing steps are usually performed. However, when the above-mentioned heat-peelable adhesive sheet is used, the interface between the heat-expandable adhesive layer and the hardened sealant is separated. The above-mentioned double-sided adhesive sheet remains attached to the support. However, when the double-sided adhesive sheet is removed from the support, there may be adhesion. A part of the adhesive layer of the sheet remains on the adherend. In this case, a cleaning step of the support is necessary, which causes a decrease in productivity.

On the other hand, when using the above-mentioned double-sided adhesive sheet, a method of attaching the thermally expandable adhesive layer to the support may also be considered. It is considered that after the sealing step, the peelability of the double-sided adhesive sheet will be improved from the support. However, the thermally expandable adhesive layer becomes very brittle after the thermally expandable microspheres expand. Therefore, after the self-supporting body is peeled off, the heat-expandable adhesive layer of the hardened seal with the double-sided adhesive sheet attached is located on the outermost layer. Therefore, part of the heat-expandable adhesive layer may easily fall off during transportation or processing in the next step. Or the thermal expansion adhesive layer may peel off. The peeled off heat-expandable adhesive layer adheres to various machines in the manufacturing environment and contaminates the machines, which must be cleaned, thus causing a decrease in productivity. In other words, in the manufacture of hardened sealing bodies, it is also necessary to suppress contamination in the manufacturing environment, eliminate the need for cleaning steps, and improve productivity.

The object of the present invention is to provide a hardened sealing body obtained by using a sealing material for a sealing object, which can effectively suppress the occurrence of positional deviation of the sealing object or the harmful effects of the adhesion of the sealing resin to the exposed surface of the sealing object, and improve the quality of the sealing object. A method of manufacturing a hardened sealing body that is efficient, suppresses contamination in the manufacturing environment, and improves productivity. [Means used to solve problems]

The inventors of the present invention discovered that in the process of using a sealing material for a sealed object to produce a hardened sealing body, by using a base material having at least an expandable base material layer containing expandable particles and a non-expandable base material layer Both sides of the adhesive sheet have a first adhesive layer and a second adhesive layer which are non-expanding adhesive layers respectively, which can solve the above problems.

That is, the present invention relates to the following [1] to [10]. [1] A method of manufacturing a hardened sealing body, which uses a base material (Y) having at least an expandable base material layer (Y1) containing expandable particles and a non-expandable base material layer (Y2), and The first adhesive layer (X1) and the second adhesive layer (X2) on both sides of the base material (Y) are non-expandable adhesive layers, and the first adhesive layer can be formed on the first adhesive layer through the expansion of the aforementioned expandable particles. A method of producing a hardened sealing body by producing uneven adhesive flakes on the adhesive surface of the layer (X1). The method has the following steps (1) to (3): ・Step (1): Apply the first adhesive layer (X1) The adhesive surface is attached to the hard support, and a sealing object is placed on part of the adhesive surface of the second adhesive layer (X2). ・Step (2): Place the aforementioned sealing object with the sealing object The step of covering at least the adhesive surface of the second adhesive layer (X2) of the peripheral portion of the object with a sealing material, and hardening the sealing material to obtain a cured sealing body in which the sealing object is sealed with the sealing material, ・Step (3): Expand the expandable particles, and in a state where the hardened sealing body is laminated on the second adhesive layer (X2), at the interface P between the hard support and the first adhesive layer (X1) Carry out the separation steps. [2] The method of manufacturing a hardened sealing body according to the above [1], wherein the adhesive sheet has a first adhesive layer (X1) on the side of the base material (Y) in front of the expandable base material layer (Y1), and The base material (Y) has the aforementioned second adhesive layer (X2) on the side of the non-expanding base material layer (Y2). [3] The method for manufacturing a hardened sealing body according to the above [1] or [2], wherein the base material (Y) has the above-mentioned expandable base material layer (Y1) and is provided on the above-mentioned expandable base material layer (Y1) The non-expanding base material layer (Y2-1) on the side of the aforementioned first adhesive layer (X1) and the non-expanding base layer (Y2-1) provided on the side of the aforementioned expanding base material layer (Y1) on the side of the aforementioned second adhesive layer (X2) Material layer (Y2-2), the storage modulus E' of the non-expandable base material layer (Y2-1) when the aforementioned expandable particles expand, is greater than the storage modulus E' of the non-expandable base material layer (Y2-1) when the aforementioned expandable particles expand. The storage modulus E' of Y2-2) is lower. [4] The method for manufacturing a hardened sealing body according to the above [1] or [2], wherein the non-expandable base material layer (Y2) exists further away from the first layer than the expandable base material layer (Y1). The position of the adhesive layer (X1), and there is no aforementioned non-expandable base material layer (Y2) between the aforementioned expandable base material layer (Y1) and the aforementioned first adhesive layer (X1), between the aforementioned expandable particles The storage modulus E' of the non-expandable base material layer (Y2) when expanded is larger than the storage modulus E' of the expandable base material layer (Y1) when the expandable particles expand. [5] The method for manufacturing a hardened sealing body according to any one of [1] to [4] above, wherein when the expandable particles are expanded in step (3), there is no separation between the layers constituting the adhesive sheet. . [6] The method for manufacturing a hardened sealing body according to any one of the above [1] to [5], wherein the expandable particles are thermally expandable particles with an expansion starting temperature (t) of 60 to 270°C. [7] The method of manufacturing a hardened sealing body as described in the above [6], wherein the thermally expandable particles have a temperature between "expansion starting temperature (t) + 10°C" and "expansion starting temperature (t) + 60°C" Heat treatment is performed to expand the thermally expandable particles. [8] The method for manufacturing a hardened sealing body according to the above [6] or [7], wherein the aforementioned expandable base material layer (Y1) is a thermally expandable base material layer (Y1-1) containing the aforementioned thermally expandable particles, and in The storage modulus E'(23) of the thermally expandable base material layer (Y1-1) at 23°C is 1.0×10 ⁶ Pa or more. [9] The method for manufacturing a hardened sealing body according to any one of the above [1] to [8], wherein the volume change rate (%) of the non-expandable base material layer (Y2) is less than 2% by volume. [10] The method for manufacturing a hardened sealing body according to any one of [1] to [9] above, wherein the sealing object is a semiconductor wafer. [Effects of the invention]

According to the manufacturing method of the hardened sealing body of the present invention, when the sealing object is obtained by using the sealing material to obtain the hardened sealing body, the occurrence of positional deviation of the sealing object or the exposure of the sealing resin to the sealing object can be effectively suppressed. It eliminates the disadvantages of surface adhesion, improves yield, suppresses pollution in the manufacturing environment, and improves productivity.

In this specification, the determination of whether the target layer is an "expandable layer" or a "non-expandable layer" is based on the volume change calculated from the following formula before and after the treatment for expansion for 3 minutes. Judgment based on rate. ・Volume change rate (%) = {(volume of the aforementioned layer after treatment - volume of the aforementioned layer before treatment)/volume of the aforementioned layer before treatment} × 100 In other words, if the volume change rate is 5 volume % or more, the layer is judged to be an "expansive layer", and if the volume change rate is less than 5 volume %, the layer is judged to be a "non-expansive layer." Furthermore, as the "treatment for expansion", for example, when the expandable particles are thermally expandable particles, it is sufficient to perform a heat treatment for 3 minutes at the expansion starting temperature (t) of the thermally expandable particles.

In this specification, "active ingredient" refers to the ingredients contained in the subject composition excluding the diluting solvent. In addition, the mass average molecular weight (Mw) is a standard polystyrene conversion value measured by the gel permeation chromatography (GPC) method. Specifically, it is a value measured based on the method described in the Examples.

In this specification, for example, "(meth)acrylic acid" means both "acrylic acid" and "methacrylic acid", and the same applies to other similar terms. In addition, regarding the preferable numerical range (for example, the range of content etc.), the lower limit value and the upper limit value described in stages can be combined independently respectively. For example, from the description of "10 to 90 is preferred, and 30 to 60 is more preferred", "preferable lower limit value (10)" and "better upper limit value (60)" can also be combined to become " 10~60".

[Method for manufacturing the hardened sealing body of the present invention] The manufacturing method of the hardened sealing body of the present invention (hereinafter also simply referred to as the "manufacturing method of the present invention") uses an expandable base material layer (Y1) containing at least expandable particles and a non-expandable base material layer. The base material (Y) of (Y2), and the first adhesive layer (X1) and the second adhesive layer (X2) each being a non-expanding adhesive layer on both sides of the base material (Y), and can be The expansion of the aforementioned expandable particles produces uneven adhesive flakes on the adhesive surface of the first adhesive layer (X1), thereby producing a hardened sealing body. In addition, the manufacturing method of the present invention has the following steps (1) to (3). ・Step (1): The step of attaching the adhesive surface of the first adhesive layer (X1) to a hard support and placing the sealing object on a part of the adhesive surface of the second adhesive layer (X2). ・Step (2): Cover the adhesive surface of the aforementioned sealing object and the second adhesive layer (X2) of at least the peripheral portion of the sealing object with a sealing material, and harden the sealing material to obtain the aforementioned sealing object. The step of creating a hardened sealing body sealed with the aforementioned sealing material. ・Step (3): Expand the expandable particles, and in a state where the hardened sealing body is laminated on the second adhesive layer (X2), at the interface between the hard support and the first adhesive layer (X1) P performs the separation step.

[Constitution of the adhesive sheet used in the manufacturing method of the present invention] FIG. 1 is a schematic cross-sectional view of an adhesive sheet used in the manufacturing method of the present invention, showing an example of the structure of the adhesive sheet. The adhesive sheet used in the manufacturing method of the present invention includes a base material (Y) having at least an expandable base material layer (Y1) and a non-expandable base material layer (Y2) as shown in Figure 1(a), and Each of the two sides of the base material (Y) is an adhesive sheet 1a of a first adhesive layer (X1) and a second adhesive layer (X2) of a non-expanding adhesive layer.

The base material (Y) of the adhesive sheet 1a shown in Figure 1(a) is a structure in which an expanding base material layer (Y1) and a non-expanding base material layer (Y2) are directly laminated. However, the base material (Y) may also consist of other components. For example, the first non-thermally expandable base material layer (Y2) may be provided on both sides of the expandable base material layer (Y1) like the base material (Y) of the adhesive sheet 1b shown in FIG. 1(b). -1) and the composition of the second non-thermally expandable base material layer (Y2-2).

Furthermore, the adhesive sheet used in one aspect of the present invention may also be composed of a release material laminated on the adhesive surface of the first adhesive layer (X1) and the adhesive surface of the second adhesive layer (X2). . In this structure, a release material that has been subjected to a release treatment on both sides is laminated on the adhesive surface of one of the first adhesive layer (X1) and the second adhesive layer (X2), and is wound. It is made of roller shape. These release materials are provided to protect the adhesive surfaces of the first adhesive layer (X1) and the second adhesive layer (X2), and are removed when the adhesive sheet is used.

Furthermore, for example, in the adhesive sheet 1a shown in Figure 1(a), the peeling force when peeling off the release material laminated on the first adhesive layer (X1) is the same as the peeling force when the peeling material laminated on the second adhesive layer (X1) If the peeling force when peeling off the release materials in X2) is at the same level, the adhesive sheet 1a may be separated and peeled together with the two release materials due to an attempt to pull the two release materials outward for peeling. Therefore, the release material laminated on the first adhesive layer (X1) and the release material laminated on the second adhesive layer (X2) are preferably designed to peel off the adhesive layers that adhere to each other. Two types of peeling materials with different strengths.

The adhesive sheet used in the manufacturing method of the present invention is adjusted so that the expansion of the aforementioned expandable particles can produce unevenness on the adhesive surface of the first adhesive layer (X1). For example, the adhesive sheet 1a shown in Figure 1(a) has a first adhesive layer (X1) in which a non-expanding adhesive layer is laminated on an expanding base material layer (Y1) containing expanding particles. Furthermore, the second adhesive layer (X2) of the non-expanding adhesive layer is laminated on the non-expanding base material layer (Y2). In the adhesive sheet 1a, when the expandable particles in the expandable base material layer (Y1) expand, unevenness is generated on the surface of the expandable base material layer (Y1), and the first adhesive layer (X1) in contact with the surface is The bumps and bumps are lifted up, and as a result, bumps and bumps may also be produced on the adhesive surface of the first adhesive layer (X1). In the manufacturing method of the present invention, as described in step (1) above, the adhesive surface of the first adhesive layer (X1) is attached to the hard support. In the above step (3), when the expandable particles are expanded, unevenness is generated on the adhesive surface of the first adhesive layer (X1), and the contact area with the hard support is reduced, so that the hard support and the first adhesive layer can be adhered to each other. The interface P of the agent layer (X1) is easily separated together with a little force. Furthermore, when the expandable particles are expanded, the interface between the expandable base material layer (Y1) and the non-expandable base material layer (Y2) can be adjusted so that they can be easily separated together with a small force.

On the other hand, as described in step (1) above, the sealing object is placed on the adhesive surface of the second adhesive layer (X2). In step (2), the placed sealing object is combined with the sealing object. The second adhesive layer (X2) on the peripheral portion of the object is covered with a sealing material, and the sealing material is hardened to form a hardened sealing body. As stipulated in the above step (3), when the expandable particles are expanded, when the hardened sealing body is laminated on the second adhesive layer (X2), between the hard support and the first adhesive layer (X1) Interface P separation. In other words, when separated by a hard support, a plurality of semiconductor wafers need to be held on the second adhesive layer (X2) of the adhesive sheet. Therefore, the adhesive surface of the second adhesive layer (X2) is preferably adjusted to maintain an adhesive force sufficient to maintain the hardened sealing body even due to expansion of the aforementioned expandable particles, and to suppress the formation of unevenness.

For example, the adhesive sheet 1a shown in Figure 1(a) has a non-expanding base material layer (Y2) on the surface of the expanding base material layer (Y1) opposite to the first adhesive layer (X1). , and a second adhesive layer (X2) is laminated on the surface of the non-expanding base material layer (Y2). In the adhesive sheet 1a, when the expandable particles expand, a non-expandable base material layer (Y2) exists. Therefore, the stress from the expandable base material layer (Y1) side due to the expansion of the expandable particles is caused by the non-expandable base material layer (Y2). The base material layer (Y2) absorbs. As a result, the formation of unevenness on the adhesive surface of the second adhesive layer (X2) laminated on the non-expanding base material layer (Y2) is suppressed, and the state in which the hardened sealant is laminated on the adhesive surface can be maintained.

Furthermore, in the adhesive sheet 1b shown in Figure 1(b), when the expandable particles expand, it is better to adjust the storage modulus E' of the first non-expandable base material layer (Y2-1) to a low level so that The adhesive surface of the first adhesive layer (X1) is uneven. On the other hand, when the expandable particles expand, it is better to adjust the storage modulus E' of the second non-thermally expandable base material layer (Y2-2) to a high level so that the adhesive surface of the second adhesive layer (X2) The formation of bumps and convexities is suppressed. That is, it is preferable to adjust the storage modulus E' of the first non-thermally expandable base material layer (Y2-1) when the expandable particles expand to be higher than the storage modulus E' of the second non-thermally expandable base material layer (Y2-1) when the expandable particles expand. The storage modulus E' of Y2-2) is lower.

When an adhesive sheet having an expandable adhesive layer containing expandable particles is used as described in Patent Document 1, and a sealing object is placed on the adhesive surface of the expandable adhesive layer to obtain a hardened seal, a seal is placed Since the expandable adhesive layer of the object contains expandable particles, the adhesive force tends to become insufficient. Therefore, during the sealing step in step (2), the position of the sealing object may be shifted, or the sealing resin of the sealing material may invade the interface between the sealing object and the expandable adhesive layer, causing the sealing resin to adhere to the sealing object. The disadvantages of exposed surfaces (such as circuit surfaces of semiconductor chips, etc.).

In addition, it is also possible to consider using a double-sided adhesive sheet with an expandable adhesive layer on one surface of the base material and a non-expandable adhesive layer on the other surface. The expandable adhesive layer is attached to the hard support. , and a method of placing a sealing object on the non-expandable adhesive layer to obtain a hardened sealing body. However, the adhesive force of the expandable adhesive layer easily becomes insufficient, and the sealing object is not fully fixed on the hard support. Therefore, the sealing object placed on the non-expanding adhesive layer is also easy to pass through the sealing material. Move when covered. Therefore, during the sealing step, the position of the sealing object may be shifted or the sealing resin may adhere to the exposed surface of the sealing object.

In addition, it can also be considered to avoid the above disadvantages by selecting an adhesive resin to make the expandable adhesive layer have high adhesive force. However, when the expandable adhesive layer has a high adhesive force, depending on the type of adhesive resin contained in the expandable adhesive layer, the expandable particles may not be fully expanded even if the expandable particles are expanded. , it is also difficult to peel off easily together. In other words, when a sealing object is placed on a high-adhesion expandable adhesive layer, it may be difficult to peel the formed hardened seal from the expandable adhesive layer. Even if it is peeled off, the hardened seal may still be damaged. The problem is that a part of the expandable adhesive layer remains on the body.

Furthermore, when a high-adhesion expandable adhesive layer is attached to a hard support, when the expandable particles are expanded and the double-sided adhesive sheet is peeled off from the hard support, some adhesive may remain on the surface of the hard support. The layer requires a cleaning step of the support, which is also a factor that reduces productivity.

In addition, the expandable adhesive layer becomes very brittle after the expandable particles expand. Starting from the hard support body, in the hardened sealing body with two-sided adhesive sheets, the expandable adhesive layer is located on the outermost layer. However, during transportation or processing in the next step, the expandable adhesive layer on the outermost layer is easily adhered. Part of the adhesive layer peels off, or the expandable adhesive layer peels off. When the peeled off expandable adhesive layer adheres to various machines in the manufacturing environment and contaminates the machines, the machines must be cleaned, thus causing a decrease in productivity.

On the other hand, the adhesive sheet used in the manufacturing method of the present invention is adjusted to have a base material (Y) having at least an expandable base material layer (Y1) containing expandable particles and a non-expandable base material layer (Y2). And when the expandable particles expand, unevenness is formed on the adhesive surface of the first adhesive layer (X1). Therefore, the degree of freedom in selecting the adhesive composition of the forming material of the first adhesive layer (X1) and the second adhesive layer (X2) is also high. In other words, unlike the expandable adhesive layer which has limitations on the adhesive resin used as described above, the first adhesive layer (X1) and the second adhesive layer (X1) can be selected without considering the expandability of the expandable particles. X2) Adhesive resin used. In addition, since the first adhesive layer (X1) attached to the hard support is a non-expanding adhesive layer and does not need to contain expandable particles, it can be fully fixed to the hard support, thereby effectively preventing the sealing object from being The position of the sealed object is displaced due to insufficient fixation between the object and the hard support, or the sealing resin adheres to the exposed surface of the sealed object.

Furthermore, when the hard support and the attached adhesive sheet are separated, they can be easily separated together, and contamination of the separated hard support can be effectively suppressed.

In addition, in the hardened sealing body with the adhesive sheet attached after separation, the expandable base material layer (Y1) containing expanded expandable particles is at least not located in the outermost layer, and compared with the adhesive layer containing expandable particles In the case of particles, there is a certain degree of intensity. Therefore, the expanded expandable base material layer (Y1) is less likely to fall off or the like. Furthermore, in the separated hardened sealing body with the adhesive sheet attached, the first adhesive layer (X1) located in the outermost layer is a non-expanding adhesive layer and does not need to contain expanding particles, so it is not easy to produce the first adhesive layer. Disadvantages such as peeling off of the agent layer (X1). Therefore, in the manufacturing method of the present invention, contamination in the manufacturing environment can be effectively suppressed, so there is no need for a cleaning step associated with contamination, and excellent productivity can be demonstrated.

[Various physical properties of the adhesive sheet] The adhesive sheet used in one aspect of the present invention generates unevenness on the adhesive surface of the first adhesive layer (X1) attached to the hard support due to the expansion of the expandable particles. The interface P between the body and the first adhesive layer (X1) can be easily separated together with a small amount of force. Here, in the adhesive sheet used in one aspect of the present invention, the peeling force (F ₁ ) when the expandable particles are expanded and separated at the interface P is usually 0~2000mN/25mm, preferably 0~1000mN/25mm. , preferably 0~150mN/25mm, further preferably 0~100mN/25mm, further preferably 0~50mN/25mm. In addition, when the peeling force (F ₁ ) is 0 mN/25mm, it also includes the case where the peeling force cannot be measured because the peeling force is too small even if the peeling force is measured by the method described in the Examples.

On the other hand, when the object to be sealed is sealed with a sealing material to obtain a hardened sealing body before expansion of the expandable particles, the occurrence of positional deviation of the object to be sealed or the impact of the sealing resin on the exposed surface of the object to be sealed is effectively suppressed. To avoid the disadvantages of adhesion and improve the yield, the higher the adhesive force of the first adhesive layer (X1), the better. From the above point of view, in the adhesive sheet used in one aspect of the present invention, the peeling force (F ₀ ) when separating at the interface P before the expansion of the expandable particles is preferably 0.05~10.0N/25mm, more preferably 0.1~8.0N/25mm, preferably 0.15~6.0N/25mm, further preferably 0.2~4.0N/25mm. Furthermore, the above-mentioned peeling force (F ₀ ) can also be regarded as the adhesion force of the first adhesive layer (X1) to the hard support.

In the adhesive sheet used in one aspect of the present invention, the ratio of the peeling force (F ₁ ) to the peeling force (F ₀ ) [(F ₁ )/(F ₀ )] is preferably 0 to 0.9, more preferably 0. ~0.8, preferably 0~0.5, and even better still 0~0.2.

In addition, the peeling force (F ₁ ) is a value measured in the environment when the expandable particles expand. For example, when the expandable particles are heat-expandable particles, the temperature conditions when measuring the peeling force (F ₁ ) may be equal to or higher than the expansion start temperature (t) of the heat-expandable particles. On the other hand, the temperature condition when measuring the peeling force (F ₀ ) may be a temperature at which the expandable particles do not expand, and is basically room temperature (23° C.). However, more specific measurement conditions and measurement methods of peeling force (F ₁ ) and peeling force (F ₀ ) are based on the methods described in the examples.

Furthermore, in the adhesive sheet used in one aspect of the present invention, at room temperature (23°C), the adhesive force of the second adhesive layer (X2) is preferably 0.1~10.0N/25mm, more preferably 0.2~8.0N /25mm, preferably 0.4~6.0N/25mm, and preferably 0.5~4.0N/25mm. In this specification, the adhesive force of the second adhesive layer (X2) means a value measured by the method described in the Examples. Next, each layer constituting the adhesive sheet used in one aspect of the present invention will be described.

＜Substrate(Y)＞ The base material (Y) of the adhesive sheet used in one aspect of the present invention includes at least an expandable base material layer (Y1) containing expandable particles and a non-expandable base material layer (Y2). In addition, as the base material (Y), like the adhesive sheet 1a shown in Figure 1(a), the expandable base material layer (Y1) and the non-expandable base material layer (Y2) can be laminated into one respectively. In this case, the first non-thermal expandable base material layer (Y2-1) and the second non-thermal expandable base material layer (Y2-1) can also be provided on both sides of the expandable base material layer (Y1) like the adhesive sheet 1b shown in Figure 1(b). The composition of the sexual base material layer (Y2-2).

Moreover, the base material (Y) of the adhesive sheet used in one aspect of the present invention may also have an adhesive layer provided between the expandable base material layer (Y1) and the non-expandable base material layer (Y2). composition. For example, when the adhesive sheet 1b is configured as shown in Figure 1(b), the expandable base material layer (Y1) may be combined with the first non-thermally expandable base material layer (Y2-1) and/or the second non-thermal expandable base material layer (Y2-1). An adhesive layer is provided between the thermally expandable base material layers (Y2-2). By providing the adhesive layer, the interlayer adhesion between the expandable base material layer (Y1) and the non-expandable base material layer (Y2) can be improved. The adhesive layer can be formed of a general adhesive or an adhesive composition of the material forming the first adhesive layer (X1) and the second adhesive layer (X2).

In one aspect of the present invention, the expansion of the expandable particles causes unevenness on the adhesive surface of the first adhesive layer (X1), and on the other hand, on the adhesive surface of the second adhesive layer (X2) From the viewpoint of an adhesive sheet in which the formation of unevenness is suppressed, the base material (Y) is preferably one having an expanding base material layer (Y1) and a non-expanding base material layer (Y2) on at least the outermost surface. This aspect can include the base material (Y) of the adhesive sheet 1a shown in Figure 1(a), or the intumescent base material layer (Y1), the adhesive layer, and the non-expanding base material layer (Y1) sequentially laminated Base material (Y) made of Y2), etc.

Furthermore, the expanding base material layer (Y1) and the non-expanding base material layer (Y2) constituting the base material (Y) are both non-adhesive layers. In the present invention, the determination of whether it is a non-adhesive layer is based on the fact that if the probe viscosity value measured according to JIS Z0237:1991 on the surface of the target layer does not reach 50mN/5mmφ, the layer is determined to be "non-adhesive". Adhesion layer". The probe viscosity values of the surfaces of the expandable base material layer (Y1) and the non-expandable base material layer (Y2) of the adhesive sheet (I) used in one aspect of the present invention are independently, usually, not It reaches 50mN/5mmφ, preferably less than 30mN/5mmφ, more preferably less than 10mN/5mmφ, still more preferably less than 5mN/5mmφ. Furthermore, in this specification, the specific method for measuring the probe viscosity value on the surface of the thermally expandable base material is based on the method described in the Examples.

In the adhesive sheet used in one aspect of the present invention, the thickness of the base material (Y) is preferably 15 to 2000 μm, more preferably 25 to 1500 μm, still more preferably 30 to 1000 μm, and still more preferably 40 to 500 μm. .

Before the expansion of the expandable particles, the thickness of the expandable base material (Y1) is preferably 10~1000 μm, more preferably 20~700 μm, more preferably 25~500 μm, and still more preferably 30~300 μm. The thickness of the non-expanding base material (Y2) is preferably 10 to 1000 μm, more preferably 20 to 700 μm, more preferably 25 to 500 μm, and still more preferably 30 to 300 μm. In addition, in this specification, for example, like the adhesive sheet 1b shown in FIG. 1(b), there is a case where a plurality of expandable base materials (Y1) or non-expandable base materials (Y2) are present through other layers. , the thickness of the above-mentioned expandable base material (Y1) or non-expandable base material (Y2) means the thickness of each respective layer.

In the adhesive sheet used in one aspect of the present invention, the thickness ratio of the expandable base material layer (Y1) and the non-thermal expandable base material layer (Y2) before expansion of the expandable particles [(Y1)/(Y2)] , preferably 0.02~200, more preferably 0.03~150, still more preferably 0.05~100.

In the adhesive sheet used in one aspect of the present invention, the expandable base material layer (Y1) before expansion of the expandable particles, and the first adhesive layer (Y1) directly laminated to the expandable base material layer (Y1) The thickness ratio [(Y1)/(X1)] of The best value is 200 or less, the best value is 60 or less, and the best value is 30 or less.

Moreover, in the adhesive sheet used in one aspect of the present invention, the thickness ratio of the non-expanding base material layer (Y2) and the second adhesive layer (X2) directly laminated with the non-expanding base material layer (Y2) [(Y2)/(X2)] is preferably 0.1 or more, more preferably 0.2 or more, still more preferably 0.3 or more, and preferably 20 or less, more preferably 10 or less, still more preferably 5 or less.

Hereinafter, the expandable base material layer (Y1) and the non-expandable base material layer (Y2) constituting the base material (Y) will be described.

＜Expansive base material layer (Y1)＞ The expandable base material layer (Y1) constituting the base material (Y) is a layer that contains expandable particles and can be expanded by a specific expansion treatment. The content of the expandable particles in the expandable base material layer (Y1) is preferably 1 to 40 mass%, more preferably 5, relative to the total mass (100 mass%) of the expandable base material layer (Y1). ~35% by mass, more preferably 10~30% by mass, and still more preferably 15~25% by mass.

Furthermore, from the viewpoint of improving the interlayer adhesion between the expandable base material layer (Y1) and other laminated layers, the surface of the expandable base material layer (Y1) may also be subjected to an oxidation method or a roughening method. Surface treatment, easy adhesion treatment, or primer treatment. Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromic acid treatment (wet type), hot air treatment, ozone, and ultraviolet irradiation treatment. Examples of the unevenness method include sand blasting and solvent treatment.

The expandable particles contained in the expandable base material layer (Y1) may be particles that expand by performing a specific treatment. Examples thereof include heat-expandable particles that expand by heating above a specific temperature or by heat-expandable particles. UV-expandable particles, etc., absorb a specific amount of ultraviolet rays and generate gas inside the particles to expand.

The maximum volume expansion rate of the expandable particles is preferably 1.5 to 100 times, more preferably 2 to 80 times, still more preferably 2.5 to 60 times, and still more preferably 3 to 40 times.

The average particle diameter of the expandable particles before expansion at 23° C. is preferably 3 to 100 μm, more preferably 4 to 70 μm, still more preferably 6 to 60 μm, and still more preferably 10 to 50 μm. In addition, the average particle diameter of the expandable particles is the volume median particle diameter (D ₅₀ ), which is measured using a laser diffraction particle size distribution measuring device (for example, "Mastersizer 3000" manufactured by Malvern Corporation). In the particle distribution of the expandable particles, the cumulative volume frequency calculated from the side with the smaller particle size of the expandable particles corresponds to 50% of the particle size.

The 90% particle diameter (D ₉₀ ) of the expandable particles before expansion at 23°C is preferably 10 to 150 μm, more preferably 20 to 100 μm, more preferably 25 to 90 μm, and still more preferably 30 to 80 μm. . In addition, the 90% particle diameter (D ₉₀ ) of the expanding particles means the particle distribution of the expanding particles measured using a laser diffraction particle size distribution measuring device (for example, "Mastersizer 3000" manufactured by Malvern Corporation). , the cumulative volume frequency calculated from the side with the smaller particle size of the expandable particles is equivalent to 90% of the particle size.

In one aspect of the present invention, the expandable particles are preferably thermally expandable particles with an expansion starting temperature (t) of 60 to 270°C. In other words, the expandable base material layer (Y1) is preferably a thermally expandable base material layer (Y1-1) containing thermally expandable particles with an expansion starting temperature (t) of 60 to 270°C. The thermally expandable base material layer (Y1- 1), preferably meeting the following requirements (1).・Requirement (1): At the expansion starting temperature (t) of the thermally expandable particles, the storage modulus E'(t) of the thermally expandable base material layer (Y1-1) is 1.0×10 ⁷ Pa or less. In addition, in this specification, the storage modulus E′ of the thermally expandable base material layer (Y1-1) at a specific temperature means a value measured by the method described in the Examples.

The above requirement (1) can be said to be an index showing the rigidity of the thermally expandable base material layer (Y1-1) just before the thermally expandable particles expand. In other words, when the heat-expandable particles expand, if the heat-expandable base material layer (Y1-1) has flexibility that satisfies the above requirement (1), unevenness will be easily formed on the surface of the heat-expandable base material layer (Y1-1). The adhesive surface of the first adhesive layer (X1) is also prone to unevenness. As a result, the hard support and the first adhesive layer (X1) can be easily separated together with a small force at the interface P.

From the above point of view, the storage modulus E'(t) specified in the requirement (1) of the thermally expandable base material layer (Y1-1) is preferably 9.0×10 ⁶ Pa or less, and more preferably 8.0×10 ⁶ Pa or less, more preferably 6.0×10 ⁶ Pa or less, still more preferably 4.0×10 ⁶ Pa or less. In addition, the flow of the expanded heat-expandable particles is suppressed, and the shape maintenance of the unevenness produced on the surface of the heat-expandable base material layer (Y1-1) is improved, and it is also easy to adhere to the surface of the first adhesive layer (X1) From the viewpoint of generating unevenness, the storage modulus E'(t) specified in the requirement (1) of the thermally expandable base material layer (Y1-1) is preferably 1.0×10 ³ Pa or more, and more preferably 1.0×10 ⁴ Pa or more, more preferably 1.0×10 ⁵ Pa or more.

Furthermore, the thermally expandable base material layer (Y1-1) preferably satisfies the following requirement (2), and more preferably satisfies both the above requirement (1) and this requirement (2).・Requirement (2): At 23°C, the storage modulus E'(23) of the thermally expandable base material layer (Y1-1) is 1.0×10 ⁶ Pa or more.

By using the thermally expandable base material layer (Y1-1) that satisfies the above requirement (2), it is possible to prevent positional deviation when the sealing object is placed on the adhesive surface of the second adhesive layer (X2), and also It can prevent the sealing object from excessively sinking into the second adhesive layer (X2).

From the above point of view, the storage modulus E' (23) of the thermally expandable base material layer (Y1-1) specified in the above requirement (2) is preferably 5.0×10 ⁶ ~5.0×10 ¹² Pa, more preferably 1.0×10 ⁷ ~1.0×10 ¹² Pa, more preferably 5.0×10 ⁷ ~1.0×10 ¹¹ Pa, further preferably 1.0×10 ⁸ ~1.0×10 ¹⁰ Pa.

The heat-expandable particles contained in the heat-expandable base material layer (Y1-1) are preferably heat-expandable particles with an expansion starting temperature (t) of 60 to 270°C. In addition, in this specification, the expansion start temperature (t) of a heat-expandable particle means the value measured based on the following method. [Measurement of expansion starting temperature (t) of thermally expandable particles] In an aluminum cup with a diameter of 6.0 mm (inner diameter of 5.65 mm) and a depth of 4.8 mm, 0.5 mg of the thermally expandable particles to be measured were added, and an aluminum lid (diameter of 5.6 mm, thickness of 0.1 mm) was placed on top to prepare a sample. Use a dynamic viscoelasticity measuring device to measure the height of the sample while applying a force of 0.01N from the top of the aluminum cover to the sample. Then, while applying a force of 0.01N with the pressure bar, heat from 20°C to 300°C at a temperature rise rate of 10°C/min, and measure the displacement in the vertical direction of the pressurizer. The displacement starting temperature is the expansion starting temperature (t).

The heat-expandable particles are preferably a microencapsulated foaming agent composed of a shell made of thermoplastic resin and an inner component contained in the shell that vaporizes when heated to a specific temperature. Examples of the thermoplastic resin constituting the shell of the microencapsulated foaming agent include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, poly Vinylidene chloride, polyethylene, etc.

Examples of the included components contained in the shell include propane, butane, pentane, hexane, heptane, octane, nonane, decane, isobutane, isopentane, isohexane, and isoheptane. Alkane, isooctane, isononane, isodecane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, neopentane, dodecane, isododecane, Cyclotridecane, hexylcyclohexane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, isotridecane, 4-methyldodecane , isotetradecane, isopentadecane, isohexadecane, 2,2,4,4,6,8,8-heptamethylnonane, isoheptadecane, isoctadecane, isopenadecane , 2,6,10,14-tetramethylpentadecane, cyclotridecane, heptylcyclohexane, n-octylcyclohexane, cyclopentadecane, nonylcyclohexane, decylcyclohexane Alkane, pentadecylcyclohexane, hexadecylcyclohexane, heptadecylcyclohexane, octadecylcyclohexane, etc. These included ingredients can be used individually or two or more types can be used in combination. The expansion starting temperature (t) of the thermally expandable particles can be adjusted by appropriately selecting the type of encapsulated components.

The expandable base material layer (Y1) is preferably formed of a resin composition (y) containing resin and expandable particles. Furthermore, the resin composition (y) may contain additives for base materials as necessary within a range that does not impair the effects of the present invention. Examples of additives for base materials include ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, smoothing agents, anti-adhesive agents, colorants, and the like. In addition, these additives for base materials may be used individually, or two or more types may be used in combination. When these additives for base materials are contained, the content of each additive for base materials is preferably 0.0001 to 20 parts by mass, and more preferably 0.001 to 10 parts by mass relative to 100 parts by mass of the resin.

The expandable particles contained in the resin composition (y) that forms the expandable base material layer (Y1) are preferably thermally expandable particles as described above. The content of the expandable particles is preferably 1 to 40 mass %, more preferably 5 to 35 mass %, and still more preferably 1 to 40 mass % relative to the total amount of active ingredients (100 mass %) of the resin composition (y). 10~30% by mass, more preferably 15~25% by mass.

The resin contained in the resin composition (y) of the forming material of the expandable base material layer (Y1) may be a non-adhesive resin or an adhesive resin. In other words, even if the resin contained in the resin composition (y) is an adhesive resin, in the process of forming the expandable base material layer (Y1) from the resin composition (y), the adhesive resin will also interact with the polymerizable compound. The polymerization reaction only requires that the obtained resin becomes a non-adhesive resin and the expandable base material layer (Y1) containing the resin becomes non-adhesive.

The mass average molecular weight (Mw) of the resin contained in the resin composition (y) is preferably 1000 to 1 million, more preferably 1000 to 700,000, and still more preferably 1000 to 500,000. In addition, when the resin is a copolymer having two or more structural units, the form of the copolymer is not particularly limited and may be any of a block copolymer, a random copolymer, and a graft copolymer.

The resin content is preferably 50 to 99 mass %, more preferably 60 to 95 mass %, and still more preferably 65 to 95 mass % relative to the total amount of active ingredients (100 mass %) of the resin composition (y). 90% by mass, and more preferably 70~85% by mass.

In one aspect of the present invention, from the viewpoint of forming an expandable base material layer (Y1) in which unevenness is easily formed on the surface when the expandable particles expand, the resin contained in the resin composition (y) is relatively small. Preferably, it contains at least one selected from the group consisting of acrylic urethane resin and olefin resin. Moreover, the above-mentioned acrylic urethane resin is preferably the following resin (U1). ・Acrylic urethane resin (U1) obtained by polymerizing a urethane prepolymer (UP) and a vinyl compound containing (meth)acrylate.

[Acrylic urethane resin (U1)] Examples of the urethane prepolymer (UP) of the main chain of the acrylic urethane resin (U1) include a reaction product of a polyol and a polyisocyanate. Furthermore, the urethane prepolymer (UP) is preferably one obtained by carrying out a chain extension reaction using a chain extension agent.

Polyols used as raw materials for urethane prepolymers (UP) include, for example, alkylene polyols, ether polyols, ester polyols, esteramide polyols, and ester/ether polyols. Alcohols, carbonate polyols, etc. These polyhydric alcohols can be used individually or in combination of 2 or more types. The polyol used in one aspect of the present invention is preferably a diol; more preferably, it is an ester type glycol, an alkylene type glycol, and a carbonate type glycol; and more preferably, it is an ester type glycol or a carbonate type glycol. diol.

Examples of ester glycols include alkanediols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, and 1,6-hexanediol; ethylene glycol; One or two or more glycols selected from diols such as diols, propylene glycol, diethylene glycol, dipropylene glycol, and alkylene glycols, together with phthalic acid, isophthalic acid, terephthalic acid, naphthalene Dicarboxylic acid, 4,4-diphenyldicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, chlorobridge acid, maleic acid Acid, fumaric acid, itaconic acid, cyclohexane-1,3-dicarboxylic acid, cyclohexane-1,4-dicarboxylic acid, hexahydrophthalic acid, hexahydroisophthalic acid, hexahydro A condensation polymer of one or more selected from dicarboxylic acids such as terephthalic acid and methylhexahydrophthalic acid and their acid anhydrides. Specific examples include polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, and polyhexamethylene isophthalate diol. , polyneopentyl adipate glycol, polyethylene propylene adipate glycol, polyethylene butylene adipate glycol, polybutylene hexamethylene adipate glycol, Polyethylene adipate glycol, poly(tetramethylene ether) adipate glycol, poly(3-methylpentane adipate) glycol, polyethylene azelate Glycol, polyethylene sebacate glycol, polybutylene azelaate glycol, polybutylene sebacate glycol and polyneopentyl terephthalate glycol, etc.

Alkylene glycols include, for example, alkylene glycols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, and 1,6-hexanediol; Alkylene glycols such as ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol; polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polybutylene glycol; polyoxyalkylene glycols such as polytetramethylene glycol; Alcohol etc.

Examples of the carbonate type diol include 1,4-tetramethylene carbonate diol, 1,5-pentamethylene carbonate diol, 1,6-hexamethylene carbonate diol, and 1,2-pentamethylene carbonate diol. Propylene glycol, 1,3-propylene carbonate diol, 2,2-dimethyl propylene carbonate diol, 1,7-heptamethylene carbonate diol, 1,8-octamide carbonate Methyl ester diol, 1,4-cyclohexane carbonate diol, etc.

Polyisocyanates used as raw materials for urethane prepolymers (UP) include aromatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, and the like. These polyvalent isocyanates can be used individually or in combination of two or more types. In addition, these polyvalent isocyanates can also be trimethylolpropane adduct type modifiers, biuret type modifiers after reacting with water, and isocyanurines containing isocyanurate rings. Acid ester modified body.

Among these, the polyvalent isocyanate used as one aspect of the present invention is particularly preferably diisocyanate; more preferably, 4,4'-diphenylmethane diisocyanate (MDI) and 2,4-toluene diisocyanate are used. One or more types selected from (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), hexamethylene diisocyanate (HMDI), and alicyclic diisocyanate.

Examples of alicyclic diisocyanates include 3-isocyanatemethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), 1,3-cyclopentane diisocyanate, and 1,3 - Cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, etc., preferably isophorone Diisocyanate (IPDI).

In one aspect of the present invention, the urethane prepolymer (UP) as the main chain of the acrylic urethane resin (U1) is a reactant of diol and diisocyanate, preferably two Linear urethane prepolymer with ethylenically unsaturated terminal groups. A method for introducing ethylenically unsaturated groups into both terminals of the linear urethane prepolymer includes the terminals of a linear urethane prepolymer obtained by reacting a diol and a diisocyanate compound. NCO group, a method of reacting with hydroxyalkyl (meth)acrylate.

Examples of hydroxyalkyl (meth)acrylate include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and (meth)acrylic acid. 2-hydroxybutyl ester, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.

The vinyl compound of the side chain of the acrylic urethane resin (U1) contains at least (meth)acrylate. (Meth)acrylate, preferably at least one selected from the group consisting of alkyl (meth)acrylate and hydroxyalkyl (meth)acrylate, more preferably a combination of alkyl (meth)acrylate and (meth)acrylate )Hydroxyalkyl acrylate.

When using alkyl (meth)acrylate and hydroxyalkyl (meth)acrylate in combination, the blending ratio of hydroxyalkyl (meth)acrylate is preferred relative to 100 parts by mass of alkyl (meth)acrylate. It is 0.1~100 parts by mass, more preferably 0.5~30 parts by mass, still more preferably 1.0~20 parts by mass, and still more preferably 1.5~10 parts by mass.

The carbon number of the alkyl group of the (meth)acrylic acid alkyl ester is preferably 1 to 24, more preferably 1 to 12, still more preferably 1 to 8, and still more preferably 1 to 3.

Examples of the hydroxyalkyl (meth)acrylate include those used for introducing ethylenically unsaturated groups into both terminals of the linear urethane prepolymer.

Examples of vinyl compounds other than (meth)acrylates include aromatic hydrocarbon vinyl compounds such as styrene, α-methylstyrene, and vinyl toluene; methyl vinyl ether, ethyl vinyl ether, etc. Vinyl ethers; vinyl acetate, vinyl propionate, (meth)acrylonitrile, N-vinylpyrrolidone, (meth)acrylic acid, maleic acid, fumaric acid, itaconic acid, methyl (Acrylamide) and other polar group-containing monomers. These can be used individually or two or more types can be used in combination.

The content of (meth)acrylate in the vinyl compound is preferably 40 to 100 mass%, more preferably 65 to 100 mass%, relative to the total amount of the vinyl compound (100 mass%). More preferably, it is 80-100 mass %, and still more preferably, it is 90-100 mass %.

The total content of alkyl (meth)acrylate and hydroxyalkyl (meth)acrylate in the vinyl compound is preferably 40 to 100 mass% relative to the total amount of the vinyl compound (100 mass%) , more preferably 65~100% by mass, still more preferably 80~100% by mass, still more preferably 90~100% by mass.

In the acrylic urethane resin (U1) used in one aspect of the present invention, the structural unit (u11) derived from the urethane prepolymer (UP) and the structural unit derived from the vinyl compound The content ratio of (u12) [(u11)/(u12)], in terms of mass ratio, is preferably 10/90~80/20, more preferably 20/80~70/30, and even more preferably 30/70 ~60/40, and even better 35/65~ 55/45.

[Olefin resin] Olefin-based resins suitable as the resin contained in the resin composition (y) include polymers having at least a structural unit derived from an olefin monomer. The above-mentioned olefin monomer is preferably an α-olefin having 2 to 8 carbon atoms, and specific examples thereof include ethylene, propylene, butene, isobutylene, 1-hexene, and the like. Among these, ethylene and propylene are particularly preferred.

Specific olefin-based resins include, for example, ultra-low density polyethylene (VLDPE, density: 880 kg/m ³ or more and less than 910 kg/m ³ ), low-density polyethylene (LDPE, density: 910 kg/m ³ or more but less than 910 kg/m 3 ). 915kg/m ³ ), medium density polyethylene (MDPE, density: 915kg/m ³ or more and less than 942kg/m ³ ), high-density polyethylene (HDPE, density: 942kg/m ³ or more), linear low density Polyethylene resin such as polyethylene; polypropylene resin (PP); polybutylene resin (PB); ethylene-propylene copolymer; olefin elastomer (TPO); ethylene-vinyl acetate copolymer (EVA); ethylene- Olefin terpolymers such as propylene-(5-ethylene-2-norbornene), etc.

In one aspect of the present invention, the olefin-based resin may be a modified olefin-based resin further subjected to at least one type of modification selected from acid modification, hydroxyl modification, and acryl modification.

For example, the acid-modified olefin resin obtained by acid-modifying an olefin resin includes a modified polymer obtained by graft-polymerizing an unsaturated carboxylic acid or anhydride thereof to the above-mentioned unmodified olefin resin. Examples of the unsaturated carboxylic acid or anhydride thereof include maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaconic acid, tetrahydrophthalic acid, aconitic acid, (meth)acrylic acid, and maleic acid. Lenic anhydride, itaconic anhydride, glutaconic anhydride, citraconic anhydride, aconitic anhydride, norbornene dicarboxylic anhydride, tetrahydrophthalic anhydride, etc. In addition, unsaturated carboxylic acid or its anhydride may be used individually or in combination of 2 or more types.

The acryl-modified olefin resin obtained by subjecting an olefin resin to acryl modification may include the above-mentioned unmodified olefin resin in the main chain and graft polymerization of an alkyl (meth)acrylate as a side chain. modified polymer. The number of carbon atoms in the alkyl group of the alkyl (meth)acrylate is preferably 1 to 20, more preferably 1 to 16, and still more preferably 1 to 12. Examples of the above-mentioned (meth)acrylic acid alkyl ester include the same compounds as those that can be selected as the monomer (a1') described below.

Examples of the hydroxyl-modified olefin-based resin obtained by subjecting olefin-based resin to hydroxyl-modification include a modified polymer obtained by graft-polymerizing a hydroxyl-containing compound on the above-mentioned unmodified olefin-based resin in the main chain. Examples of the above-mentioned hydroxyl-containing compound include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 2-hydroxy(meth)acrylate. Butyl ester, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and other hydroxyalkyl (meth)acrylates; unsaturated alcohols such as vinyl alcohol and allyl alcohol, etc.

(Resins other than acrylic urethane resin and olefin resin) In one aspect of the present invention, the resin composition (y) may contain resins other than acrylic urethane resins and olefin resins within a range that does not impair the effects of the present invention. Examples of such resins include vinyl-based resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, and ethylene-vinyl alcohol copolymer; polyethylene terephthalate , polybutylene terephthalate, polyethylene naphthalate and other polyester resins; polystyrene; acrylonitrile-butadiene-styrene copolymer; cellulose triacetate; polycarbonate; not Polyurethane equivalent to acrylic urethane resin; polymethylpentene; polystyrene; polyether ether ketone; polyether sulfide; polyphenylene sulfide; polyether imine, polyether imine Polyamide-based resins such as amines; polyamide-based resins; acrylic resins; fluorine-based resins, etc.

However, when the expandable particles expand, they become the expandable base material layer (Y1) whose surface is prone to unevenness, and the resin composition (y) contains resins other than acrylic urethane resin and olefin resin. The content ratio is smaller, the better. The content ratio of resins other than acrylic urethane resin and olefin resin is preferably less than 30 parts by mass, based on 100 parts by mass of the total amount of resin contained in the resin composition (y). It is more preferably less than 20 parts by mass, more preferably less than 10 parts by mass, still more preferably less than 5 parts by mass, still more preferably less than 1 part by mass.

[Solvent-free resin composition (y1)] An aspect of the resin composition (y) includes blending an oligomer having an ethylenically unsaturated group with a mass average molecular weight (Mw) of 50,000 or less, an energy-beam polymerizable monomer, and the above-mentioned expandable particles. , and a solvent-free resin composition (y1) without blending solvent. In the solvent-free resin composition (y1), no solvent is blended, and the energy-beam-polymerizable monosystem contributes to improving the plasticity of the oligomer. By irradiating the coating film formed of the solvent-free resin composition (y1) with energy rays, when the expandable particles expand, it is easy to form an expandable base material layer (Y1) that is easy to have unevenness on the surface, and it is particularly easy to form a layer that satisfies the The thermally expandable base material layer (Y1-1) of the above requirements (1) and (2).

In addition, the type, shape, and blending amount (content) of the expandable particles blended in the solvent-free resin composition (y1) are the same as in the resin composition (y) and are as described above.

The mass average molecular weight (Mw) of the oligomer contained in the solvent-free resin composition (y1) is 50,000 or less, preferably 1,000 to 50,000, more preferably 2,000 to 40,000, and still more preferably 3,000 to 35,000. , and even better is 4000~30000.

Furthermore, the oligomer may be any one having an ethylenically unsaturated group with a mass average molecular weight of 50,000 or less among the resins contained in the resin composition (y), and is preferably the above-mentioned urethane. Prepolymer (UP). Furthermore, a modified olefin-based resin having an ethylenically unsaturated group can also be used as the oligomer.

In the solvent-free resin composition (y1), the total content of the aforementioned oligomers and energy-beam polymerizable monomers is preferred relative to the total amount (100% by mass) of the solvent-free resin composition (y1). The content is 50 to 99 mass%, more preferably 60 to 95 mass%, still more preferably 65 to 90 mass%, and still more preferably 70 to 85 mass%.

Examples of the energy ray polymerizable monomer include isocamphenyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentyl (meth)acrylate, and dicyclopentenoxy (meth)acrylate. Alicyclic polymerizable compounds such as ester, cyclohexyl (meth)acrylate, adamantyl (meth)acrylate, tricyclodecyl acrylate, etc.; phenyl hydroxypropyl acrylate, benzyl acrylate, phenol ethylene oxide Aromatic polymerizable compounds such as alkane-modified acrylates; heterocyclic polymerizable compounds such as tetrahydrofuran methyl (meth)acrylate, morpholine acrylate, N-vinyl pyrrolidone, N-vinyl caprolactam, etc. Compounds etc. These energy ray polymerizable monomers may be used individually or in combination of two or more types.

The blending ratio of the aforementioned oligomer and the energy ray polymerizable monomer (the aforementioned oligomer/energy ray polymerizable monomer) is preferably 20/80~90/10, more preferably 30/70~85/15 , and even better is 35/65~80/20.

In one aspect of the present invention, the solvent-free resin composition (y1) is preferably further blended with a photopolymerization initiator. By containing a photopolymerization initiator, the hardening reaction can fully proceed even when irradiated with energy rays of relatively low energy.

Examples of the photopolymerization initiator include 1-hydroxy-cyclohexyl-phenyl-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, and benzylphenyl sulfide. Ether, tetramethylthiuram monosulfide, azobisisobutyronitrile, bibenzyl, biacetyl, 8-chloroanthraquinone, etc. These photopolymerization initiators may be used individually or in combination of two or more types.

The blending amount of the photopolymerization initiator is preferably 0.01 to 5 parts by mass, and more preferably 0.01 to 4 parts by mass relative to the total amount (100 parts by mass) of the aforementioned oligomer and energy ray polymerizable monomer. parts, preferably 0.02~3 parts by mass.

<Non-expanding base material layer (Y2)> Examples of materials for forming the non-expanding base material layer (Y2) constituting the base material (Y) include paper, resin, metal, and the like. Examples of paper materials include thin paper, medium quality paper, high quality paper, impregnated paper, coated paper, coated paper, sulfuric acid paper, cellophane paper, and the like. Examples of the resin include polyolefin resins such as polyethylene and polypropylene; vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, and ethylene-vinyl alcohol copolymer; Polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polystyrene; acrylonitrile-butadiene-styrene copolymer; triacetic acid Cellulose; polycarbonate; polyurethane, acrylic modified polyurethane and other urethane resins; polymethylpentene; polystyrene; polyether ether ketone; polyether styrene ; Polyphenylene sulfide; polyetherimide, polyimide and other polyimide-based resins; polyamide-based resins; acrylic resins; fluorine-based resins, etc. Examples of metals include aluminum, tin, chromium, titanium, and the like.

These forming materials may be composed of one type, or two or more types may be used in combination. The non-expanding base material layer (Y2) that uses two or more forming materials in combination includes laminating paper with a thermoplastic resin such as polyethylene, or forming a metal layer on the surface of a resin film or sheet containing the resin. Filmmakers etc. Furthermore, the formation method of the metal layer may include, for example, a method of evaporating the above-mentioned metal by a PVD method such as vacuum evaporation, sputtering, ion plating, or the like, or using a general adhesive for a metal foil composed of the above-mentioned metal. Methods of attaching, etc.

Furthermore, from the viewpoint of improving the interlayer adhesion between the non-expanding base material layer (Y2) and other laminated layers, when the non-expanding base material layer (Y2) contains resin, the non-expanding base material layer (Y2) The surface of Y2) can also be subjected to surface treatment such as oxidation or roughening, adhesion treatment, or primer treatment in the same manner as the above-mentioned expandable base material layer (Y1).

In addition, when the non-expanding base material layer (Y2) contains a resin, it may contain the above-mentioned base material additive which may be contained in the resin composition (y) at the same time as the resin.

Preferably, the non-expanding base material layer (Y2) exists at a position further away from the above-mentioned first adhesive layer (X1) than the above-mentioned expanding base material layer (Y1), and the expanding base material layer (Y1) and There is no non-expanding base material layer (Y2) between the first adhesive layers (X1). When the aforementioned expanding particles expand, the storage modulus E' of the aforementioned non-expanding base material layer (Y2) is compared with The storage modulus E' of the expandable base material layer (Y1) when the expandable particles expand is larger. In this way, since there is no non-expandable base material layer (Y2) between the expandable base material layer (Y1) and the first adhesive layer (X1), the expandable particles expand in the expandable base material layer (X1). The unevenness produced on the surface of Y1) is transmitted to the first adhesive layer (X1) without passing through the non-expanding base material layer (Y2), and unevenness is also easily generated on the adhesive surface of the first adhesive layer (X1). In addition, when the expandable particles expand, the storage modulus E' of the non-expandable base material layer (Y2) is larger than the storage modulus E' of the expandable base material layer (Y1). Therefore, when the expandable particles expand, the storage modulus E' is suppressed. The surface of the expandable base material layer (Y1) on the non-expandable base material layer (Y2) side has unevenness. As a result, the surface of the expandable base material layer (Y1) on the first adhesive layer (X1) side becomes uneven. It is easy to produce unevenness, so the adhesive surface of the first adhesive layer (X1) is also easy to produce unevenness. When the aforementioned expandable particles expand, the storage modulus E' of the non-expandable base material layer (Y2) is preferably as mentioned above from the viewpoint that the adhesive surface of the first adhesive layer (X1) is prone to unevenness. It is more than 1.0 MPa, and it is preferable from the viewpoint of the ease of attaching and peeling operations, the production of unevenness on the adhesive surface of the second adhesive layer (X2), and the ease of handling of the roll-shaped body. is 1.0×10 ³ MPa or less. From this point of view, when the expandable particles expand, the storage modulus E' of the non-expandable base material layer (Y2) is preferably 1.0~5.0×10 ² MPa, more preferably 1.0×10 ¹ ~1.0×10 ² MPa, and more preferably 5.0×10 ¹ ~1.0×10 ³ MPa. In addition, from the above point of view and from the viewpoint of preventing positional deviation when the semiconductor wafer is attached to the adhesive surface of the second adhesive layer (X2), the storage mold of the non-expanding base material layer (Y2) is stored at 23°C. The number E'(23) is preferably 5.0×10 ¹ ~ 5.0×10 ⁴ MPa, more preferably 1.0×10 ² ~1.0×10 ⁴ MPa, and still more preferably 5.0×10 ² ~5.0×10 ³ MPa. The non-expanding base material layer (Y2) is a non-expanding layer determined based on the above method. Therefore, the volume change rate (%) of the non-expandable base material layer (Y2) calculated from the above formula is less than 5% by volume, preferably less than 2% by volume, more preferably less than 1% by volume, It is more preferably less than 0.1 volume %, and still more preferably less than 0.01 volume %.

In addition, the non-expandable base material layer (Y2) may contain thermally expandable particles as long as the volume change rate is within the above range. For example, by selecting the resin contained in the non-expandable base material layer (Y2), even if thermally expandable particles are contained, the volume change rate can be adjusted to the above range. However, the smaller the content of thermally expandable particles in the non-expandable base material layer (Y2), the better. The specific content of thermally expandable particles is usually less than 3% by mass, preferably less than 1% by mass, and more preferably less than 1% by mass relative to the total mass (100% by mass) of the non-expandable base material layer (Y2). It is less than 0.1 mass %, more preferably less than 0.01 mass %, still more preferably less than 0.001 mass %.

<1st adhesive layer (X1), 2nd adhesive layer (X2)> The adhesive sheet used in one aspect of the present invention has a first adhesive layer (X1) and a second adhesive layer (X2) which are non-expandable adhesive layers. In the manufacturing method of the present invention, the adhesive surface of the first adhesive layer (X1) is attached to the hard support, and the sealing object is placed on the adhesive surface of the second adhesive layer (X2) to form a hardened seal. body.

The first adhesive layer (X1) and the second adhesive layer (X2), by being non-expanding adhesive layers, can effectively prevent the position of the sealing object caused by insufficient fixation between the sealing object and the hard support. Misalignment or adhesion of the sealing resin to the exposed surface of the sealing object. In addition, since the first adhesive layer (X1) is a non-expanding adhesive layer, in addition to the above effects, in the cured sealing body with the adhesive sheet attached after being separated from the cured support body, the first adhesive layer can be suppressed The layer (X1) may fall off and contaminate various machines in the manufacturing environment.

The first adhesive layer (X1) is required to have high adhesion to the hard support before expansion of the expandable particles contained in the expandable base material layer (Y1), so that the sealing object can be fully fixed to the hard support. The nature of the body. From this point of view, the shear storage modulus G'(23) of the first adhesive layer (X1) at 23°C is preferably 1.0×10 ⁸ Pa or less, more preferably 5.0×10 ⁷ Pa or less. , and more preferably 1.0×10 ⁷ Pa or less.

On the other hand, when the expandable particles in the expandable base material layer (Y1) expand, it is also required that the unevenness produced on the surface of the expandable base material layer (Y1) is also formed in the first adhesive layer ( X1) The degree of rigidity of the adhesive surface. From this point of view, the shear storage modulus G'(23) of the first adhesive layer (X1) at 23°C is preferably 1.0×10 ⁴ Pa or more, and more preferably 5.0×10 ⁴ Pa or more. , and more preferably 1.0×10 ⁵ Pa or more.

In addition, the second adhesive layer (X2) is required to have adhesion not only to the object to be sealed but also to the hardened sealing body formed by sealing the object to be sealed with a sealing material. In addition, it is necessary to prevent the sealing object from being excessively sunk into the second adhesive layer (X2). From this point of view, at 23°C, the shear storage modulus G' (23) of the second adhesive layer (X2) is preferably 1.0×10 ⁴ ~1.0×10 ⁸ Pa, and more preferably 5.0× 10 ⁴ ~5.0×10 ⁷ Pa, more preferably 9.0×10 ⁴ ~1.0×10 ⁷ Pa. In addition, in this specification, the shear storage modulus G' (23) of the first adhesive layer (X1) and the second adhesive layer (X2) means the value measured by the method described in the Example.

The thickness of the first adhesive layer (X1) is preferably 1 to 60 μm, more preferably 2 to 50 μm, still more preferably 3 to 40 μm, and still more preferably 5 to 30 μm.

The thickness of the second adhesive layer (X2) is preferably 1 to 60 μm, more preferably 2 to 50 μm, still more preferably 3 to 40 μm, and still more preferably 5 to 30 μm.

The first adhesive layer (X1) and the second adhesive layer (X2) can be formed from the adhesive composition (x) containing an adhesive resin. In addition, the adhesive composition (x) may also contain additives for adhesives such as a cross-linking agent, a tackifier, a polymerizable compound, a polymerization initiator, etc., if necessary. Each component contained in the adhesive composition (x) will be described below.

(adhesive resin) The adhesive resin used in one aspect of the present invention may be a polymer that has adhesive properties alone and has a mass average molecular weight (Mw) of 10,000 or more. The mass average molecular weight (Mw) of the adhesive resin used in one aspect of the present invention is preferably 10,000 to 2 million, more preferably 20,000 to 1.5 million, and even more preferably 30,000 from the perspective of improving the adhesive force. ~1 million.

Specific adhesive resins include, for example, acrylic resins, urethane resins, rubber-based resins such as polyisobutylene-based resins, polyester-based resins, olefin-based resins, polysilicone-based resins, and polyvinyl ethers. System resin, etc. These adhesive resins can be used alone or two or more types can be used in combination. In addition, when these adhesive resins are copolymers having two or more structural units, the form of the copolymer is not particularly limited and can be any of block copolymers, random copolymers, and graft copolymers. .

The adhesive resin used in one aspect of the present invention may also be an energy-beam curable adhesive resin in which a polymerizable functional group is introduced into the side chain of the above-mentioned adhesive resin. For example, by forming the second adhesive layer (X2) from an energy-ray-curable adhesive composition containing an energy-ray-curable adhesive resin, the adhesive force can be reduced by irradiating energy rays, and the resulting adhesive layer can be cured. The sealing body is easily separated from the second adhesive layer (X2). Examples of the polymerizable functional group include (meth)acryl group, vinyl group, and the like. In addition, the energy rays may include ultraviolet rays or electron beams, and ultraviolet rays are preferred. Furthermore, the material for forming the adhesive layer that can be irradiated with energy rays to reduce the adhesive force may be an energy ray-hardening adhesive composition containing a monomer or oligomer with a polymerizable functional group.

These energy ray curable adhesive compositions preferably further contain a photopolymerization initiator. By containing a photopolymerization initiator, the hardening reaction can fully proceed even when irradiated with energy rays of relatively low energy. Examples of the photopolymerization initiator include the same ones blended in the above-mentioned solvent-free resin composition (y1). The content of the photopolymerization initiator is preferably 0.01 to 10 parts by mass, or more, relative to 100 parts by mass of energy ray curable adhesive resin or 100 parts by mass of monomers or oligomers with polymerizable functional groups. Preferably, it is 0.03~5 parts by mass, and more preferably, it is 0.05~2 parts by mass.

In one aspect of the present invention, from the viewpoint of exhibiting excellent adhesive force, the adhesive resin preferably contains an acrylic resin. In particular, since the first adhesive layer (X1) is formed from an adhesive composition containing an acrylic resin, unevenness can be easily formed on the surface of the first adhesive layer.

The content ratio of the acrylic resin in the adhesive resin is preferably 30 to 100 mass %, more preferably, relative to the total amount (100 mass %) of the adhesive resin contained in the adhesive composition (x) The content is 50 to 100 mass%, more preferably 70 to 100 mass%, and still more preferably 85 to 100 mass%.

The content of the adhesive resin is preferably 35 to 100 mass %, more preferably 50 to 100 mass %, and still more preferably 35 to 100 mass % relative to the total amount of active ingredients (100 mass %) of the adhesive composition (x). The content is 60 to 98% by mass, and more preferably 70 to 95% by mass.

(cross-linking agent) In one aspect of the present invention, when the adhesive composition (x) contains an adhesive resin having a functional group, the adhesive composition (x) preferably further contains a cross-linking agent. The cross-linking agent reacts with the adhesive resin having a functional group, and uses the functional group as the starting point for cross-linking to cross-link the adhesive resins with each other.

Examples of the cross-linking agent include isocyanate-based cross-linking agents, epoxy-based cross-linking agents, aziridine-based cross-linking agents, metal chelate-based cross-linking agents, and the like. These cross-linking agents may be used alone or in combination of two or more types. Among these cross-linking agents, isocyanate-based cross-linking agents are particularly preferred from the viewpoint of improving cohesion and adhesion, and from the viewpoint of ease of acquisition.

The content of the cross-linking agent is appropriately adjusted according to the number of functional groups in the adhesive resin. It is preferably 0.01 to 10 parts by mass, and more preferably 0.03 to 100 parts by mass of the adhesive resin with functional groups. 7 parts by mass, and more preferably 0.05~5 parts by mass.

(Tackifier) In one aspect of the present invention, the adhesive composition (x) may further contain a tackifier from the viewpoint of further improving the adhesive force. In this specification, "tackifier" is a component that assists in improving the adhesive force of the above-mentioned adhesive resin. It refers to an oligomer with a mass average molecular weight (Mw) of less than 10,000, which is different from the above-mentioned adhesive resin. . The mass average molecular weight (Mw) of the tackifier is preferably 400~10000, more preferably 500~8000, and still more preferably 800~5000.

Examples of the tackifier include rosin-based resin, terpene-based resin, styrene-based resin, pentene produced by thermal decomposition of naphtha, isoprene, piperine, 1,3-pentadiene, and the like. C5 petroleum resins obtained by copolymerization of C5 fractions, C9 petroleum resins obtained by copolymerization of C9 fractions of indene, vinyl toluene, etc. produced by thermal decomposition of naphtha, and hydrogenated resins obtained by hydrogenation of these, etc. .

The softening point of the tackifier is preferably 60~170°C, more preferably 65~160°C, and still more preferably 70~150°C. In addition, in this specification, the "softening point" of a tackifier means the value measured based on JIS K 2531. The tackifier can be used alone, or two or more types with different softening points or structures can be used in combination. In addition, when two or more types of plural tackifiers are used, the weighted average of the softening points of the plural tackifiers preferably falls within the above range.

The content of the tackifier is preferably 0.01 to 65 mass %, more preferably 0.1 to 50 mass %, and more preferably 0.1 to 50 mass %, relative to the total amount (100 mass %) of the active ingredients of the adhesive composition (x). The content is 1 to 40% by mass, and more preferably 2 to 30% by mass.

(Additives for adhesives) In one aspect of the present invention, the adhesive composition (x) may contain, in addition to the above-mentioned additives, adhesive additives used in general adhesives within the scope that does not impair the effects of the present invention. Examples of such additives for adhesives include antioxidants, softeners (plasticizers), rust inhibitors, pigments, dyes, retardants, reaction accelerators (catalysts), ultraviolet absorbers, and antistatic agents. Furthermore, these additives for adhesives may be used individually, or two or more types may be used in combination.

When these adhesive additives are contained, the content of each adhesive additive is preferably 0.0001 to 20 parts by mass, and more preferably 0.001 to 10 parts by mass relative to 100 parts by mass of the adhesive resin.

Furthermore, both the first adhesive layer (X1) and the second adhesive layer (X2) are non-expanding adhesive layers, and preferably do not substantially contain expanding particles. Here, "substantially does not contain expanding particles" means that the first adhesive layer (X1) and the second adhesive layer (X2) do not contain expanding particles with a specific intention. Therefore, it is not excluded that expandable particles are mixed as impurities in the first adhesive layer (X1) and the second adhesive layer (X2). Specifically, the content of the expandable particles is based on the total amount of active ingredients (100% by mass) of the adhesive composition (x) of the forming material of the first adhesive layer (X1) and the second adhesive layer (X2). ), or relative to the total mass (100 mass%) of the first adhesive layer (X1) and the second adhesive layer (X2), preferably less than 1 mass%, more preferably less than 0.1 mass% , and more preferably less than 0.01 mass %, and still more preferably less than 0.001 mass %.

＜Peel-off material＞ The adhesive sheet used in one aspect of the present invention may be further laminated with a release material on the adhesive surfaces of the first adhesive layer (X1) and the second adhesive layer (X2). Examples of the release material include those using a release sheet subjected to two-sided release processing or a release sheet subjected to one-side release treatment, and a release agent is coated on the base material for the release material.

Examples of the base material for the release material include papers such as high-quality paper, cellophane paper, and kraft paper; polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate resin, and the like; Ester resin film; polypropylene resin, polyethylene resin, olefin resin film, etc., plastic film, etc.

Examples of the release agent include rubber elastomers such as silicone resin, olefin resin, isoprene resin, butadiene resin; long-chain alkyl resin, alkyd resin, fluorine resin, etc. .

The thickness of the peeling material is not particularly limited, but is preferably 10 to 200 μm, more preferably 25 to 170 μm, and still more preferably 35 to 80 μm.

[Each step of the manufacturing method of the hardened sealing body of the present invention] The manufacturing method of the present invention is a method of manufacturing a hardened sealing body using the above-mentioned adhesive sheet, and has the following steps (1) to (3). ・Step (1): The step of attaching the adhesive surface of the first adhesive layer (X1) to a hard support and placing the sealing object on a part of the adhesive surface of the second adhesive layer (X2). ・Step (2): Cover the adhesive surface of the aforementioned sealing object and the second adhesive layer (X2) of at least the peripheral portion of the sealing object with a sealing material, and harden the sealing material to obtain the aforementioned sealing object. The step of creating a hardened sealing body sealed with the aforementioned sealing material. ・Step (3): Expand the expandable particles, and in a state where the hardened sealing body is laminated on the second adhesive layer (X2), at the interface between the hard support and the first adhesive layer (X1) P performs the separation step.

Figure 2 is a schematic cross-sectional view in steps (1) to (3) of the manufacturing method of the hardened sealing body of the present invention. Steps (1) to (3) will be described below with appropriate reference to FIG. 2 .

＜Step (1)＞ Figure 2(a) is a schematic cross-sectional view in step (1) when using the adhesive sheet 1a shown in Figure 1(a). Step (1), as shown in Figure 2(a), is to attach the adhesive surface of the first adhesive layer (X1) of the adhesive sheet 1a to the hard support 50, and attach it to the second adhesive layer (X2) The step of placing the sealing object 60 on a part of the adhesive surface. In this step, it is preferable to place the sealing object 60 in such a manner that the exposed surface 61 contacts a part of the adhesive surface of the second adhesive layer (X2). In addition, the sealing target object placed on a part of the adhesive surface of the second adhesive layer (X2) may be only one, or may be a plurality of objects as shown in Figure 2(a). When placing a plurality of sealing objects, it is preferable to place them so that the distance between adjacent sealing objects becomes constant.

Furthermore, Figure 2 shows a state in which the adhesive sheet 1a shown in Figure 1(a) is used. However, when adhesive sheets having other structures are used, the rigid support and the adhesive sheet can be stacked or placed in sequence in the same manner. , and semiconductor chips, the adhesive surface of the first adhesive layer (X1) of the adhesive sheet is preferably adhered to the hard support, and the adhesive surface of the second adhesive layer (X2) is preferably adhered to the exposed surface of the sealing object.

Furthermore, step (1) is preferably performed in an environment where the expandable particles do not expand. For example, when using heat-expandable particles as the expandable particles, step (1) only needs to be carried out at a temperature that does not reach the expansion starting temperature (t) of the heat-expandable particles. Specifically, it is preferably between 0 and 80 ℃ environment (when the expansion start temperature (t) is 60 ~ 80 ℃, it is carried out in an environment that has not reached the expansion start temperature (t)).

The hard support is preferably attached to the entire adhesive surface of the first adhesive layer (X1) of the adhesive sheet. Therefore, the hard support is preferably plate-shaped. In addition, the area of the surface of the hard support adhered to the first adhesive layer (X1) is preferably greater than the area of the adhesive surface of the first adhesive layer (X1), as shown in FIG. 2 .

Materials constituting the hard support include, for example, metallic materials such as SUS; non-metallic inorganic materials such as glass and silicon wafers; epoxy resin, ABS resin, acrylic resin, engineering plastic, super engineering plastic, and polyimide resin. , resin materials such as polyamide imide resin; composite materials such as glass epoxy resin, etc. Among these, SUS, glass, and silicon wafers are particularly preferred. Furthermore, engineering plastics include nylon, polycarbonate (PC), and polyethylene terephthalate (PET). Super engineering plastics include polyphenylene sulfide (PPS), polyether sulfide (PES), and polyether ether ketone (PEEK).

The thickness of the hard support is preferably from 20 μm to 50 mm, more preferably from 60 μm to 20 mm.

The Young's modulus of the hard support fully fixes the semiconductor chip to the hard support, effectively suppressing the positional deviation of the sealing object in step (2) or the adhesion of the sealing resin to the exposed surface of the sealing object. From the perspective of harmful effects, it is preferably 1.0 GPa or more, more preferably 5.0 GPa or more, still more preferably 10 GPa or more, and still more preferably 20 GPa or more. Furthermore, in this specification, the Young's modulus of the hard support is a value measured at room temperature (25°C) according to the static Young's modulus test method of JIS Z2280:1993.

On the other hand, the sealing object placed on a part of the adhesive surface of the second adhesive layer (X2) includes, for example, semiconductor chips, semiconductor wafers, compound semiconductors, semiconductor packages, electronic components, sapphire substrates, displays, Substrates for panels, etc. Furthermore, the sealed object placed thereon may be composed of the same species, or may be composed of two or more species of different species.

The exposed surface of the sealing object refers to the surface adjacent to the adhesive surface of the second adhesive layer (X2) and not covered by the sealing material. Specifically, it is equivalent to the circuit surface. In the manufacturing method of the present invention, the sealing object is fully fixed on the hard support, so during the sealing step (2), the harmful effects of the sealing resin adhering to the exposed surface of the sealing object can be effectively suppressed. For example, when the sealing resin adheres to the circuit surface, the wiring of the circuit may be disconnected, which may cause a decrease in yield. However, according to the manufacturing method of the present invention, such disadvantages can be suppressed.

Examples of the method of placing the sealed object include the pick and place method using a device such as a flip chip bonder, a die bonder, or the batch transfer method using a transfer device. In addition, the layout, arrangement number, etc. of the arrangement of the sealing objects may be appropriately determined according to the target package form, production quantity, etc.

The hardened sealing body manufactured by the manufacturing method of the present invention is preferably used for FOWLP. Therefore, the sealing object is preferably a semiconductor wafer. Conventionally known semiconductor wafers can be used, and the circuit surface thereof can be formed with an integrated circuit composed of circuit elements such as transistors, resistors, and capacitors. The semiconductor wafer used in one aspect of the present invention can be formed on one surface of a substrate composed of silicon, SiC (silicon carbide), gallium, arsenic, etc. by etching, lift-off, etc. Semiconductor wafers with circuits are obtained by cutting them. Furthermore, the method of obtaining a semiconductor wafer from a semiconductor wafer may be a stealth dicing method, a dicing before grinding method, or other methods.

The exposed surface of the semiconductor chip placed on the adhesive surface of the second adhesive layer (X2) is preferably a circuit surface on which a circuit is formed. By placing the circuit surface of the semiconductor chip on the adhesive surface of the second adhesive layer (X2), the circuit surface of the semiconductor chip can be protected during the process of step (2). On the other hand, the surface of the semiconductor wafer opposite to the circuit surface (hereinafter also referred to as the "back surface") is the side that is covered with a sealing material in the next step, and is usually a flat surface on which circuits, electrodes, etc. are not formed.

Here, it is preferably used in applications such as FOWLP, FOPLP, etc., where the semiconductor wafer is covered with a sealing material in an area larger than the wafer size. Not only the circuit surface of the semiconductor wafer, but also the surface area of the sealing material is formed. Encapsulation of the wiring layer. Therefore, the semiconductor chip is a part of the adhesive surface placed on the second adhesive layer (X2), preferably a plurality of semiconductor wafers, placed on the adhesive surface in a state of being spaced and arranged at certain intervals; More preferably, a plurality of semiconductor wafers are placed on the adhesive surface in a matrix state with certain intervals and arranged in a plurality of rows and columns. The distance between the semiconductor chips may be appropriately determined depending on the target package form and the like.

＜Step (2)＞ Step (2), as shown in FIG. 2(b) , covers the aforementioned sealing object 60 and the adhesive surface of at least the peripheral portion of the second adhesive layer (X2) of the sealing object 60 with a sealing material 70. (Hereinafter also referred to as "coating process"), the step of hardening the sealing material 70 (hereinafter also referred to as "hardening process") to obtain the cured sealing body 80 in which the sealing object 60 is sealed with the sealing material 70 .

In the covering process of step (2), the entire exposed surface of the sealing object is covered with a sealing material. When a plurality of sealing objects are placed at the same time, the sealing material is preferably filled in the gaps between the sealing objects. Come to be covered. Alternatively, as shown in FIG. 2( b ), the sealing material 70 may be used to cover the entire adhesive surface of the sealing object 60 and the second adhesive layer (X2).

Sealing material has the function of protecting the sealed object and its accompanying elements from the external environment. The sealing material used in the manufacturing method of the present invention is preferably a thermosetting sealing material containing a thermosetting resin from the viewpoint of operability. The sealing material may be solid in the form of particles, grains, or films at room temperature, or may be liquid in the form of a composition. From the viewpoint of workability, the sealing resin of the sealing material is preferably in the form of a film. film.

The coating method can be appropriately selected according to the type of sealing material among the methods used in the conventional sealing step. Specific coating methods include, for example, roll lamination method, vacuum pressing method, vacuum lamination method, spin coating method, die coating method, transfer molding method, compression molding molding method, and the like.

The coating treatment and hardening treatment in step (2) are preferably carried out in an environment where the expandable particles do not expand. For example, when using heat-expandable particles as the expandable particles, step (2) only needs to be carried out at a temperature that does not reach the expansion starting temperature (t) of the heat-expandable particles. Specifically, it is preferably between 0 and 80 ℃ environment (when the expansion start temperature (t) is 60 ~ 80 ℃, it is carried out in an environment that has not reached the expansion start temperature (t)).

Then, after performing the coating process, the sealing material is hardened to obtain a hardened sealing body in which the sealing object is sealed with the sealing material. Moreover, the coating step and the thermal hardening step may be performed separately. However, when the sealing material is heated in the coating step, the sealing material may be directly thermally cured by the heating, and the coating step and the thermal hardening step may be performed simultaneously.

＜Step (3)＞ Step (3), in order to expand the aforementioned expandable particles, in a state where the aforementioned hardened sealing body is laminated on the second adhesive layer (X2), at the interface between the aforementioned hard support and the first adhesive layer (X1) P performs the separation step. FIG. 2(c) shows a state in which the expandable particles in the expandable base material layer (Y1) are expanded and separated at the interface P between the hard support 50 and the first adhesive layer (X1).

In this step, the method of expanding the expandable particles is appropriately selected depending on the type of the expandable particles. For example, when using heat-expandable particles as the expandable particles, heat treatment is performed at a temperature higher than the expansion starting temperature (t) of the heat-expandable particles to expand the heat-expandable particles. At this time, the "temperature above the expansion start temperature (t)" is preferably above the "expansion start temperature (t) + 10°C" and below "the expansion start temperature (t) + 60°C", more preferably It is "expansion start temperature (t) + 15°C" or more and "expansion start temperature (t) + 40°C" or less.

In the manufacturing method of the present invention, an adhesive sheet having an expandable base material layer (Y1) containing expandable particles is used, and through the expansion of the expandable particles, the first adhesive layer (X1) attached to the hard support is ) has concavities and convexities on its adhesive surface, thereby adjusting it so that it can be separated at the interface P between the hard support and the first adhesive layer (X1). Therefore, contamination of the hard support such as a part of the first adhesive layer (X1) remaining on the surface of the hard support after separation can be suppressed, and the cleaning step of the hard support can be omitted, thereby improving productivity.

Furthermore, in this step, when expanding the expandable particles, it is preferable that the layers constituting the adhesive sheet are not separated. In other words, preferably as shown in FIG. 2(c) , through step (3), all the layers that do not remain part of the adhesive sheet on the surface of the hard support 50 are removed. Generally speaking, after the adhesive sheet is separated from the hard support, a new adhesive sheet is attached again, and the same steps are performed. At this time, when the layers constituting the adhesive sheet are separated and a part of the layer of the adhesive sheet remains on the surface of the hard support, a step for removing the layer is necessary.

On the other hand, in this step, when the expandable particles are expanded, the layers constituting the adhesive sheet are not separated, so that the above-mentioned problem does not occur, and the productivity of manufacturing the hardened sealing body can be further improved. In addition, as mentioned above, after the separation of the hardened sealing body with the adhesive sheet attached, the first adhesive layer (X1) located on the outermost layer of the adhesive sheet is a non-expanding adhesive layer, so the first adhesive is not easily produced Disadvantages such as peeling off of layer (X1). From this point of view, pollution problems in the manufacturing environment are also suppressed, which becomes a factor that can further improve productivity.

Furthermore, in the hardened sealing body obtained after removing the adhesive sheet, the occurrence of positional deviation of the sealing object and the adhesion of the sealing resin to the exposed surface of the sealing object are effectively suppressed. Therefore, according to the manufacturing method of the present invention, the yield in manufacturing such a hardened sealing body can be improved.

Furthermore, the obtained hardened sealing body can also be subsequently subjected to the steps of grinding the sealing material of the hardened sealing body until the surface of the sealing object is exposed, the step of rewiring the circuit surface, forming external electrode pads, and Steps for connecting external electrode pads to external terminal electrodes, etc. Furthermore, after connecting the external terminal electrodes to the hardened sealing body, the semiconductor device may be manufactured into individual pieces. [Example]

The present invention is specifically illustrated by the following examples, but the present invention is not limited to the following examples. In addition, the physical property values in the following production examples and examples are values measured by the following method.

＜Mass average molecular weight (Mw)＞ A gel permeation chromatography device (manufactured by Tosoh Co., Ltd., product name "HLC-8020") was used to measure under the following conditions, and the value measured in terms of standard polystyrene was used. (Measurement conditions) ・Column: "TSK guard column HXL-L", "TSK gel G2500HXL", "TSK gel G2000HXL" and "TSK gel G1000HXL" are linked in this order (all manufactured by Tosoh Corporation) ・Pipe string temperature: 40℃ ・Developing solvent: Tetrahydrofuran ・Flow rate: 1.0mL/min

<Measurement of the average particle diameter and 90% particle diameter (D ₉₀ ) of the expandable particles> Measure the target expandability using a laser diffraction particle size distribution measuring device (for example, "Mastersizer 3000" manufactured by Malvern Corporation). Particle distribution of particles. Then, from this particle distribution, the particle diameter corresponding to 50% of the cumulative volume frequency calculated from the side with the smaller particle diameter of the expandable particles is the "average particle diameter", and the particle diameter corresponding to 90% of the cumulative volume frequency is It is "90% particle diameter (D ₉₀ )".

<Measurement of thickness of each layer> It is measured using a constant pressure thickness measuring instrument manufactured by Teclock Co., Ltd. (Model: "PG-02J", standard specification: based on JIS K6783, Z1702, Z1709).

＜Storage modulus E’ of the thermally expandable base material layer (Y1)＞ The formed thermally expandable base material layer (Y1) was made into a size of 5 mm in length, 30 mm in width, and 200 μm in thickness, and the one with the peeling material removed was used as a test sample. Using a dynamic viscoelasticity measuring device (manufactured by TA Instruments, product name "DMAQ800"), the measurement was performed under the conditions of a test start temperature of 0°C, a test end temperature of 300°C, a temperature rise rate of 3°C/min, a vibration frequency of 1Hz, and an amplitude of 20μm. The storage modulus E' of the test sample at a specific temperature.

<Shear storage modulus G’ of the first adhesive layer (X1) and the second adhesive layer (X2)> Cut the formed first adhesive layer (X1) and second adhesive layer (X2) into circles with a diameter of 8 mm, remove the peeling material, and stack them into a thickness of 3 mm, which is used as a test sample. Using a viscoelasticity measuring device (manufactured by Anton Paar, device name "MCR300"), under the conditions of a test start temperature of 0°C, a test end temperature of 300°C, a temperature rise rate of 3°C/min, and a vibration frequency of 1Hz, the torsional shear was measured. This method is used to determine the shear storage modulus G' of the test sample at a specific temperature.

<Probe viscosity value> Cut the substrate layer to be measured into a square with a side of 10 mm, and then leave it to stand for 24 hours in an environment of 23°C and 50% RH (relative humidity) to prepare a test sample. In an environment of 23°C and 50% RH (relative humidity), use a tacking testing machine (manufactured by Nippon Special Test Equipment Co., Ltd., product name "NTS-4800") to measure the test in accordance with JIS Z0237:1991 The probe viscosity value on the sample surface. Specifically, after a stainless steel probe with a diameter of 5mm is brought into contact with the surface of the test sample for 1 second with a contact load of 0.98N/ ^cm2 , the necessary time is measured to make the probe leave the surface of the test sample at a speed of 10mm/second. force, and use the obtained value as the probe viscosity value of the test sample.

<Measurement of the adhesive force of the second adhesive layer (X2)> On the adhesive surface of the second adhesive layer (X2) formed on the release film, a PET film with a thickness of 50 μm (manufactured by Toyobo Co., Ltd., product name "Cosmoshine A4100") was laminated as an adhesive to the base material flakes. Then remove the peeling film, and attach the exposed adhesive surface of the second adhesive layer (X2) to the adherend's stainless steel plate (SUS304 No. 360 grinding) in an environment of 23°C and 50%RH (relative humidity) After letting it stand for 24 hours, under the same environment, based on JIS Z0237:2000, the adhesion force at 23°C was measured by the 180° peeling method at a tensile speed of 300mm/min.

＜Young’s modulus of rigid support＞ According to the static Young's modulus test method of JIS Z2280:1993, it is measured at room temperature (25°C).

Production Example 1 (Synthesis of Acrylic Urethane Resin) (1) Synthesis of urethane prepolymer) In a reaction vessel under a nitrogen environment, 100 parts by mass (solid content ratio) of polycarbonate diol with a mass average molecular weight of 1,000 is mixed with isophorone diisocyanate, so that the hydroxyl groups of the polycarbonate diol and isophorone diisocyanate are The equivalent ratio of the isocyanate group of the isocyanate was 1/1, and 160 parts by mass of toluene was further added, and while stirring in a nitrogen environment, the mixture was reacted at 80° C. for more than 6 hours until the isocyanate group concentration reached the theoretical amount. Next, a solution of 1.44 parts by mass (solid content ratio) of 2-hydroxyethyl methacrylate (2-HEMA) diluted with 30 parts by mass of toluene was added, and the reaction was further carried out at 80° C. for 6 hours until the isocyanate groups at both ends were eliminated to obtain A urethane prepolymer with a mass average molecular weight of 29,000.

(2) Synthesis of acrylic urethane resin In a reaction vessel under a nitrogen atmosphere, 100 parts by mass (solid content ratio) of the urethane prepolymer obtained in Production Example 1, 117 parts by mass (solid content ratio) of methyl methacrylate (MMA), and 5.1 parts by mass (solid content ratio) of 2-hydroxyethyl acrylate (2-HEMA), 1.1 parts by mass (solid content ratio) of 1-thioglycerol, and 50 parts by mass of toluene were heated to 105°C while stirring. Then, 2.2 parts by mass (solid content ratio) of a radical initiator (manufactured by Japan Finechem Co., Ltd., product name "ABN-E") was added dropwise to 210 parts by mass of toluene in the reaction vessel while maintaining 105°C for 4 hours. diluted solution. After completion of the dropping, the reaction was carried out at 105° C. for 6 hours to obtain a solution of an acrylic urethane resin with a mass average molecular weight of 105,000.

Production Example 2 (Preparation of Adhesive Sheet) When producing the following adhesive sheet, the details of the adhesive resin, additives, heat-expandable particles, base material and release material used to form each layer are as follows. <Adhesive resin> ・Acrylic copolymer (i): Has a raw material list derived from 2-ethylhexyl acrylate (2EHA)/2-hydroxyethyl acrylate (HEA) = 80.0/20.0 (mass ratio) The structural unit of the body is an acrylic copolymer with a Mw of 600,000.・Acrylic copolymer (ii): Derived from n-butyl acrylate (BA)/methyl methacrylate (MMA)/2-hydroxyethyl acrylate (HEA)/acrylic acid=86.0/8.0/5.0/1.0( An acrylic copolymer with a Mw600,000 unit of raw material monomers (mass ratio). <Additive> ・Isocyanate cross-linking agent (i): Manufactured by Tosoh Co., Ltd., product name "Coronate L", solid content concentration: 75 mass%. <Thermal expandable particles> ・Thermal expandable particles (i): manufactured by Kureha Co., Ltd., product name "S2640", expansion starting temperature (t) = 208°C, average particle diameter before expansion at 23°C (D ₅₀ ) =24μm, 90% particle diameter before expansion at 23℃ (D ₉₀ )=49μm. <Releasable material> ・Releasable film: Made by Lindec Co., Ltd., product name "SP-PET382150", one side of the polyethylene terephthalate (PET) film is provided with a polysiloxane-based release film The thickness of the peeling agent layer formed by the agent is 38 μm.・Light release film: Made by Lindec Co., Ltd., product name "SP-PET381031", one side of the PET film is provided with a release agent layer made of polysilicone release agent, thickness: 38 μm.

(1) Formation of the first adhesive layer (X1): 100 parts by mass of the solid content of the above-mentioned acrylic copolymer (i) for the adhesive resin, and 5.0 parts by mass of the above-mentioned isocyanate cross-linking agent (i) (solid content) ratio), dilute it with toluene, stir evenly, and prepare an adhesive composition with a solid content concentration (active ingredient concentration) of 25 mass%. Then, apply the adhesive composition on the surface of the release agent layer of the above-mentioned re-peelable film to form a coating film, and dry the coating film at 100° C. for 60 seconds to form a first adhesive layer of non-expanding adhesive layer with a thickness of 5 μm. agent layer (X1). Furthermore, at 23°C, the shear storage modulus G' (23) of the first adhesive layer (X1) is 2.5×10 ⁵ Pa.

(2) To form the second adhesive layer (X2), 0.8 parts by mass (solid content) of the above-mentioned isocyanate cross-linking agent (i) is mixed with 100 parts by mass of the solid content of the above-mentioned acrylic copolymer (ii) for the adhesive resin. ratio), dilute it with toluene, stir evenly, and prepare an adhesive composition with a solid content concentration (active ingredient concentration) of 25 mass%. Then, the adhesive composition was coated on the surface of the release agent layer of the light release film to form a coating film, and the coating film was dried at 100° C. for 60 seconds to form a second adhesive layer (X2) with a thickness of 10 μm. Furthermore, at 23°C, the shear storage modulus G' (23) of the second adhesive layer (X2) is 9.0×10 ⁴ Pa. Furthermore, the adhesive force of the second adhesive layer (X2) measured based on the above method was 1.0N/25mm. Furthermore, it is obvious that the probe viscosity value of the second adhesive layer (X2) and the aforementioned first adhesive layer (X1) is 50mN/5mmφ or more, so the measurement of the probe viscosity value is omitted.

(3) Preparation of base material (Y) To 100 parts by mass of the solid content of the acrylic urethane resin obtained in Production Example 1, 6.3 parts by mass (solid content ratio) of the above-mentioned isocyanate cross-linking agent (i) and dioctyltin as a catalyst were blended 1.4 parts by mass (solid content ratio) of bis(2-ethylhexanoate) and the thermally expandable particles (i) mentioned above were diluted with toluene and stirred uniformly to prepare a resin composition with a solid content concentration (active ingredient concentration) of 30 mass %. things. In addition, the content of the thermally expandable particles (i) was 20 mass % with respect to the total amount of active ingredients (100 mass %) in the obtained resin composition. Then, on the surface of a 50 μm-thick polyethylene terephthalate (PET) film (manufactured by Toyobo Co., Ltd., product name "Cosmoshine A4100", probe viscosity value: 0 mN/5 mmφ) as a non-expanding base material On, the resin composition was applied to form a coating film, and the coating film was dried at 100° C. for 120 seconds to form an expandable base material layer (Y1) with a thickness of 50 μm. Here, the above-mentioned PET film corresponds to the non-expanding base material layer (Y2).

Furthermore, as a sample for measuring the physical property values of the expandable base material layer (Y1), the resin composition was applied to the surface of the release agent layer of the above-mentioned light release film to form a coating film, and the coating film was dried at 100°C for 120 Seconds, an expandable base material layer (Y1) with a thickness of 50 μm is formed in the same manner. Then, based on the above measurement method, the storage modulus and probe viscosity value of the expandable base material layer (Y1) at each temperature were measured. The measurement results are as follows.・Storage modulus E'(23)=2.0×10 ⁸ Pa at 23℃ ・Storage modulus E'(208)=5.0×10 ⁵ Pa at 208℃ ・Probe viscosity value=0mN/5mmφ Also, The storage modulus and probe viscosity value of the above-mentioned PET film, that is, the non-expanding base material layer (Y2) at each temperature were measured. The measurement results are as follows.・Storage modulus E'(23)=1.0×10 ³ MPa at 23℃ ・Storage modulus E'(208)=0.8×10 ² MPa at 208℃ ・Probe viscosity value=0mN/5mmφ

(4)Lamination of each layer The non-expandable base material layer (Y2) of the base material (Y1) produced in the above (1-3) is bonded to the second adhesive layer (X2) formed in the above (2), and the thermally expandable base material is The material layer (Y1) is bonded to the first adhesive layer (X1) formed in the above (1). Then, the heavy peeling film/1st adhesive layer (X1)/expandable base material layer (Y1)/non-expanding base material layer (Y2)/2nd adhesive layer (X2)/light peeling are laminated in this order. Adhesive sheet made of thin film.

In addition, based on the above method, the peeling force (F ₀ ) and (F ₁ ) of the produced adhesive sheet were measured according to the following method. As a result, peeling force (F ₀ )=0.23N/25mm, peeling force (F ₁ )=0mN/25mm, and the ratio of peeling force (F ₁ ) to peeling force (F ₀ ) [(F ₁ )/(F ₀ )] is 0.

<Measurement of Peeling Force (F ₀ )> After the prepared adhesive sheet was left to stand in an environment of 23°C and 50% RH (relative humidity) for 24 hours, the heavy peeling film of the adhesive sheet was removed, and all the adhesive sheets were removed. The exposed first adhesive layer (X1) is attached to the silicon wafer. Next, the end of the silicon wafer with the adhesive sheet attached is fixed to the lower chuck of a universal tensile testing machine (manufactured by Orientec, product name "Tensilon UTM-4-100"), and the upper chuck is fixed and adhered flakes. Then, under the same environment as above, based on JIS Z0237:2000, the interface of the silicon wafer and the first adhesive layer (X1) of the adhesive sheet was removed by the 180° peeling method at a stretching speed of 300 mm/min. The peeling force measured when P is peeled off is referred to as "peeling force (F ₀ )".

<Measurement of peeling force (F ₁ )> Remove the heavy peeling film of the produced adhesive sheet, attach the exposed first adhesive layer (X1) to the silicon wafer, and heat it at 240°C for 3 minutes. The heat-expandable particles in the heat-expandable base material layer (Y1) are expanded. Thereafter, in the same manner as the measurement of the above-mentioned peeling force (F ₀ ), the peeling force measured when the interface P of the silicon wafer and the first adhesive layer (X1) of the adhesive sheet is peeled under the above-mentioned conditions is regarded as the "peeling force". (F ₁ )". Furthermore, in the measurement of peeling force (F ₁ ), when trying to fix the adhesive sheet with the upper chuck of the universal tensile testing machine, if the adhesive sheet (I) is completely separated from the silicon wafer and cannot be fixed, the end The peeling force (F ₁ ) at this time was measured as "0mN/25mm".

Example 1 ＜Step (1)＞ The adhesive sheet produced in Production Example 2 was cut into a square size of 230 mm×230 mm. Use a tape laminating machine for back grinding (manufactured by Lintec Co., Ltd., device name "RAD-3510F/12") to peel off the heavy release film of the cut adhesive sheet and expose the first adhesive layer (X1) The adhesive surface is attached to a hard support (material: silicon, thickness: 725μm, Young's modulus: 30GPa). Then, the light release film was further peeled off, and 9 semiconductor wafers were placed at certain intervals on the adhesive surface of the exposed second adhesive layer (X2) (the size of each wafer was 6.4 mm in length × 6.4 in width). × 200μm thick (#2000) rectangular parallelepiped shape), so that the circuit surface on which the circuit is formed is in contact with the adhesive surface.

＜Step (2)＞ The adhesive surfaces of the nine aforementioned semiconductor wafers and the second adhesive layer (X2) of at least the peripheral portion of the semiconductor wafer are covered with a thermosetting sealing resin film of the sealing material, and a vacuum heating and pressure laminating machine is used. ("7024HP5" manufactured by ROHM and HAAS), the sealing resin film is thermally cured to produce a cured sealing body in which the semiconductor wafer is sealed with a sealing material. Sealing conditions are as follows. ・Preheating temperature: pedestal and diaphragm are both 100℃ ・Vacuum: 60 seconds ・Dynamic suppression mode: 30 seconds ・Static suppression mode: 10 seconds ・Sealing temperature: 180℃×60 minutes Furthermore, during the coating with the sealing resin film as described above, no positional shift of the semiconductor wafer was observed.

＜Step (3)＞ The temperature in the system containing the hard support, the adhesive sheet, and the hardened sealing body is set to 240°C, which is higher than the expansion starting temperature (208°C) of the thermally expandable particles (i), and heating is performed at the same temperature for 3 minutes. handle. After the heat treatment, the interface between the hard support and the first adhesive layer (X1) can be easily separated together. At this time, the aforementioned cured sealing system on the second adhesive layer (X2) maintains a laminated state, and no separation occurs between the layers constituting the adhesive sheet. Therefore, no residue of the first adhesive layer (X1) was found on the surface of the hard support after the adhesive sheets were separated, and no contamination was seen. It can be considered that the surface of the hard support does not need to be cleaned again. Furthermore, the semiconductor wafer sealed in the obtained cured sealing body did not shift in position, and no adhesion of the sealing resin was observed on the circuit surface. Furthermore, regarding the hardened sealing body with the adhesive sheet attached after being separated from the hard support, no disadvantages such as the peeling off of the first adhesive layer (X1) located on the outermost layer of the adhesive sheet were observed, which can be said to be good in the manufacturing environment. Pollution generation is suppressed.

1a, 1b‧‧‧Adhesive flakes (X1)‧‧‧1st adhesive layer (X2)‧‧‧Second adhesive layer (Y)‧‧‧Substrate (Y1)‧‧‧Expansive base material layer (Y2)‧‧‧Non-expanding base material layer (Y2-1)‧‧‧1st non-expandable base material layer (Y2-2)‧‧‧Second non-expanding base material layer 50‧‧‧hard support 60‧‧‧Sealed objects 61‧‧‧Exposed surface 70‧‧‧Sealing material 80‧‧‧hardened sealing body

[Fig. 1] A schematic cross-sectional view of an adhesive sheet showing an example of the structure of the adhesive sheet used in the method of manufacturing a semiconductor wafer of the present invention. [Fig. 2] A schematic cross-sectional view of steps (1) to (3) of the semiconductor wafer manufacturing method of the present invention.

Claims (10)

A method for manufacturing a hardened sealing body, which uses a base material (Y) having at least an expandable base material layer (Y1) containing expandable particles and a non-expandable base material layer (Y2), and the base material (Y) Both sides of Y) are the first adhesive layer (X1) and the second adhesive layer (X2) which are non-expandable adhesive layers, and can be formed on the first adhesive layer (X1) through the expansion of the aforementioned expandable particles. ) to produce concave and convex adhesive flakes on the adhesive surface to produce a hardened sealing body. The method has the following steps (1)~(3): ‧Step (1): Apply the adhesive surface of the first adhesive layer (X1) The step of attaching the sealing object to a hard support and placing it on a part of the adhesive surface of the second adhesive layer (X2). Step (2): Place the aforementioned sealing object with at least one of the sealing objects. Step (3) of covering the adhesive surface of the second adhesive layer (X2) of the peripheral portion with a sealing material and hardening the sealing material to obtain a cured sealing body in which the sealing object is sealed with the sealing material. ): The expansion particles are expanded, and the hardened sealing body is laminated on the second adhesive layer (X2), and then separated at the interface P between the hard support and the first adhesive layer (X1). Step; and the aforementioned intumescent base material layer (Y1) and the aforementioned non-expanding base material layer (Y2) constituting the aforementioned base material (Y) are both non-adhesive layers. The method for manufacturing a hardened sealing body according to claim 1, wherein the adhesive sheet has a first adhesive layer (X1) on the side of the base material (Y) and the expandable base material layer (Y1), and on the base material (Y) The non-expandable base layer (Y2) side has the second adhesive layer (X2). The method for manufacturing a hardened sealing body according to claim 1, wherein the base material (Y) has the intumescent base material layer (Y1), and the first adhesive layer (Y1) is provided on the intumescent base material layer (Y1). The non-expanding base material layer (Y2-1) on the X1) side, and the non-expanding base material layer (Y2-2) provided on the aforementioned second adhesive layer (X2) side of the aforementioned expanding base material layer (Y1) ), the storage modulus E' of the non-expandable base material layer (Y2-1) when the aforementioned expandable particles expand, is compared with the storage modulus E' of the non-expandable base material layer (Y2-2) when the aforementioned expandable particles expand. Modulus E' is lower. The method for manufacturing a hardened sealing body according to claim 1 or 2, wherein the non-expandable base material layer (Y2) exists further away from the first adhesive layer (X1) than the intumescent base material layer (Y1). position, and there is no non-expandable base material layer (Y2) between the aforementioned expandable base material layer (Y1) and the aforementioned first adhesive layer (X1). When the aforementioned expandable particles expand, the aforementioned non-expandable base material layer (Y2) The storage modulus E' of the expandable base material layer (Y2) is larger than the storage modulus E' of the expandable base material layer (Y1) when the expandable particles expand. The manufacturing method of the hardened sealing body of claim 1 or 2, wherein in the step (3) When the expandable particles are expanded, the layers constituting the adhesive sheet are not separated. The method for manufacturing a hardened sealing body according to claim 1 or 2, wherein the aforementioned expandable particles are thermally expandable particles with an expansion starting temperature (t) of 60 to 270°C. For example, the manufacturing method of the hardened sealing body of claim 6, wherein the heat treatment is performed between the "expansion starting temperature (t) + 10°C" and "expansion starting temperature (t) + 60°C" of the thermally expandable particles, to expand the thermally expandable particles. The manufacturing method of the hardened sealing body of claim 6, wherein the aforementioned expandable base material layer (Y1) is a thermally expandable base material layer (Y1-1) containing the aforementioned thermally expandable particles, and the thermally expandable base material layer at 23°C The storage modulus E'(23) of (Y1-1) is 1.0×10 ⁶ Pa or more. The method for manufacturing a hardened sealing body according to claim 1 or 2, wherein the volume change rate (%) of the non-expandable base material layer (Y2) is less than 2% by volume. The method for manufacturing a hardened sealing body according to claim 1 or 2, wherein the sealing object is a semiconductor wafer.