JP2020009971A - Individualized sheet - Google Patents

Abstract

To provide an individualized sheet capable of individualizing an adherend without performing an expanding step for division.SOLUTION: The individualized sheet for being pasted to an adherend to individualize the adherend from a division starting point formed on the adherend includes: a substrate (Y); an adhesive layer (X1); and expandable particles that expand when predetermined energy is applied to at least one of the substrate (Y) and the adhesive layer (X1).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a singulated sheet that singulates an adherend using a division starting point as a starting point.

2. Description of the Related Art There is known a technique in which an adhesive sheet is attached to an adherend, and a starting point of division such as a modified portion or a fragile portion formed on the adherend is cut to separate the adherend.
For example, in Patent Literature 1, an adhesive sheet is attached to a semiconductor wafer 1 (an adherend) and a tension is applied to the adhesive sheet to cut a fragile layer 31 (division starting point) formed on the adherend. A dicing step of dividing the adherend into individual pieces (hereinafter, such a step is referred to as a "expanding step for division") is described, and a method of dividing the adherend into individual pieces is described.

JP 2014-195102 A

  However, in the expanding step for dividing, a force is applied to the adherend in a tensile direction perpendicular to or perpendicular to the dividing plane of the dividing starting point, so that the dividing position is not stable, and the adherend is formed by singulation. The individual pieces to be broken are likely to be broken or cracked.

  An object of the present invention is to provide an individualized sheet that can singulate an adherend without performing an expanding step for division.

  The present invention has adopted the configuration described in the claims.

  ADVANTAGE OF THE INVENTION According to this invention, an individualized sheet | seat which can singulate an adherend can be provided, without implementing a expanding step for division | segmentation.

It is a cross section showing an example of an individualized sheet of the first mode of the present invention. It is a cross section showing an example of an individualized sheet of a 2nd mode of the present invention. It is a cross section showing an example of an individualized sheet of the third aspect of the present invention. It is a cross section showing an example of an individualized sheet of a 4th mode and a 5th mode of the present invention. It is a figure showing the mode of use of an individualized sheet of one embodiment of the present invention. It is a figure showing the mode of use of the individualized sheet of one mode of the present invention in an example.

In the present specification, the determination as to whether the target layer is the “expandable layer” or the “non-expandable layer” is made after performing the expansion process for expanding for 3 minutes, and before and after the expansion process. Is determined based on the volume change rate calculated from the following equation.
Volume change rate (%) = {(volume of the layer after treatment−volume of the layer before treatment) / volume of the layer before treatment} × 100
That is, if the volume change rate is 5% or more, the layer is determined to be an “expandable layer”, and if the volume change rate is less than 5%, the layer is a “non-expandable layer”. Judge.
As the “expansion treatment”, for example, when the expandable particles are heat-expandable particles that expand by heating, heat treatment may be performed at the expansion start temperature of the heat-expandable particles for 3 minutes. When the expandable particles are infrared expandable particles that expand when irradiated with infrared light, an infrared irradiation process may be performed for 3 minutes at an infrared intensity at which expansion of the infrared expandable particles starts.

  In the present specification, the “active ingredient” refers to a component excluding a diluting solvent among components contained in a target composition.

  In the present specification, the mass average molecular weight (Mw) is a value in terms of standard polystyrene measured by a gel permeation chromatography (GPC) method, and specifically, a value measured based on the method described in Examples. It is.

  In this specification, "(meth) acrylic acid" indicates both "acrylic acid" and "methacrylic acid", and the same applies to other similar terms.

  In the present specification, the lower limit and the upper limit described stepwise in a preferable numerical range (for example, a range such as the content) can be independently combined. For example, from the description "preferably 10 to 90, more preferably 30 to 60", "preferable lower limit (10)" and "more preferable upper limit (60)" are combined to obtain "10 to 60". You can also.

  In the present specification, the X axis, the Y axis, and the Z axis are in a relationship of being orthogonal to each other. The X axis and the Y axis are axes within a predetermined plane. The Z axis is an axis orthogonal to the predetermined plane. When describing the singulated sheet of the present invention, the laminating direction (thickness direction) of the singulated sheet is defined as the Z axis, and a plane orthogonal to the laminating direction is defined as the predetermined plane. In the following description, the predetermined plane is also referred to as “XY plane”.

  Hereinafter, first, the configuration of the singulated sheet of the present invention will be described, and then the components of the singulated sheet, the method of using the singulated sheet, and the manufacturing method will be described in order.

[Configuration of Individualized Sheet of the Present Invention]
The singulated sheet of the present invention is a singulated sheet that is attached to an adherend and cuts off the division starting point formed on the adherend to divide the adherend into individual pieces. Y) and the pressure-sensitive adhesive layer (X1), and at least one of the base material (Y) and the pressure-sensitive adhesive layer (X1) contains expandable particles that expand when given energy is applied. In the individualized sheet of the present invention, the adherend is attached to the pressure-sensitive adhesive layer (X1).

  The singulated sheet of the present invention contains expandable particles that expand when at least one of the base material (Y) and the pressure-sensitive adhesive layer (X1) is applied with a predetermined energy. Therefore, when predetermined energy is applied to a part of the individualized sheet, the expandable particles expand in the energy application sheet portion to which the predetermined energy is applied, and countless convex portions are formed. On the other hand, in the energy non-applied sheet portion to which the predetermined energy has not been applied, the expandable particles do not expand. When a predetermined energy is applied to the singulated sheet attached to the adherend by such a mechanism, the expandable particles expand, and the adherend is subjected to a shearing direction parallel to the division plane of the division start point. Alternatively, a force is applied in a shearing direction that is nearly parallel, and the starting point of division is used as a starting point to cause cracking and individualization.

Here, an example of a method for singulating an adherend using the singulated sheet of the present invention will be specifically described.
As shown in FIGS. 5A and 5B, the individualized sheet 1 is attached to the adherend WF having the first reforming section MTY and the second reforming section MTX as the reforming section MT which is the division starting point. Of the pressure-sensitive adhesive layer (X1). In addition, the modified portion MT may be formed before being attached to the individualized sheet 1 or may be formed after being attached to the individualized sheet 1. Then, at the position where the energy is applied, the energy applying unit 31 forms a linear application area LG in which the energy application area extends in a predetermined direction. Next, as shown in FIG. 5 (A), while maintaining the state where the line-shaped giving region LG extends in the first modified portion MTY direction and hits the singulated sheet 1, the energy irradiation means 31 is singulated. The sheet 1 is moved from one end ASX1 to the other end ASX2. Note that the energy is heat, infrared, ultraviolet, visible light, sound waves, X-rays, gamma rays, and the like, and is preferably heat or infrared, but the properties, characteristics, properties, materials, composition, The energy is not particularly limited as long as the energy can expand the expandable particles in consideration of the configuration and the configuration.
When energy is applied to the singulated sheet 1, the expandable particles SG expand in the energy applying sheet portion to form countless convex portions CV, and the adherend WF moves from one end WFX1 to the other end WFX2. By being partially lifted one after another, a force in the shear direction is applied to the adherend WF. When a force in the shear direction is applied to the adherend WF, the first reformed portion MTY is triggered and a crack CKY occurs, and the adherend WF is divided into a plurality of strips extending in the Y-axis direction. It becomes the adherend WFS.
Next, as shown in FIG. 5B, while maintaining the state where the line-shaped giving region LG extends in the direction of the second modified portion MTX and hits the singulated sheet 1, the energy irradiation means 31 is singulated. The sheet 1 is moved from one end ASY1 to the other end ASY2. Thereby, in the energy imparting sheet portion, the expandable particles SG further expand, the countless convex portions CV expand, and the strip-shaped adherend WFS is partially lifted from one end WFY1 to the other end WFY2 one after another. As a result, a force in the shear direction is applied to the strip-shaped adherend WFS. When a force in the shearing direction is applied to the strip-shaped adherend WFS, the second modified portion MTX is triggered and a crack CKX is generated, and the strip-shaped adherend WFS is separated into individual pieces and the crack CKX and the tip A plurality of individual pieces CP are formed with the crack CKY formed in the above. Here, the individual body CP thus formed has a reduced contact area with the pressure-sensitive adhesive layer (X1), so that the adhesive strength with the pressure-sensitive adhesive layer (X1) is also reduced, and the pressure-sensitive adhesive layer (X1) It is in a state where it can be easily removed from.
In addition, in the method for separating the adherend shown in FIGS. 5A and 5B, a force is applied to the adherend WF in the shearing direction, so that the dividing position is stabilized, and the expanding step for dividing is performed. In comparison with the individual pieces, individual pieces CP are less likely to be broken in the individual pieces CP formed by the individualization. In addition, in the method for separating the adherend shown in FIGS. 5A and 5B, the line-shaped application region LG can be stopped at a predetermined position or the application of energy can be stopped. It is also possible to selectively separate only a part of the adherend WF. On the other hand, in the case of the expanding step for division, since the entire adherend is individually singulated, it is not possible to selectively divide only a part of the adherend.
Note that, as shown in FIG. 5C, the line-shaped giving region LG (not shown) has a predetermined angle (for example, the first reformed portion MTY direction) with respect to the first reformed portion MTY direction and the second reformed portion MTX direction. The energy irradiating means 31 extends from one end ASXY1 of the individualized sheet 1 to the other end ASXY2 of the individualized sheet 1 while extending in a direction inclined by 45 degrees with respect to the part MTY direction and maintaining the state of hitting the individualized sheet 1. You may move it. In this case, the adherend WF is partially lifted from one end WFXY1 to the other end WFXY2 one after another, so that a force is applied in the shear direction of the adherend WF, and the first modified portion MTY and the second Both the reformed portion MTX and the crack CKX and the crack CKY occur at the same time. In this case, the adherend WF is separated into individual pieces CP by only one scan of the line-shaped application area LG. Note that, in this case, the predetermined angle at which the line-shaped imparting region LG is inclined with respect to the direction of the first modified portion MTY and the second modified portion MTX is set so that both the first modified portion MTY and the second modified portion MTX are aligned. Any angle may be used as long as the crack CKX and the crack CKY are simultaneously generated. Specifically, an angle larger than 0 degree and smaller than 90 degrees with respect to the first modified section MTY direction or the second modified section MTX, for example, 1 degree, 5 degrees, 10 degrees, 45 degrees, and 60 degrees , 89 degrees, or any other angle.

As described above, the individualized sheet of the present invention may be any sheet as long as the expandable particles SG expand when a predetermined energy is applied, and a force in the shear direction can be applied to the adherend. Therefore, the expandable particles SG may be included in the pressure-sensitive adhesive layer (X1) as long as the expandable particles SG can expand and apply a force in the shear direction to the adherend when predetermined energy is applied. Then, it may be contained in the substrate (Y), or may be contained in both the substrate (Y) and the pressure-sensitive adhesive layer (X1).
In addition, as shown in FIGS. 5A to 5C, the expandable particles SG are formed of the base material (Y) and the pressure-sensitive adhesive layer ( It is preferably dispersed in at least one of X1), and more preferably dispersed uniformly in the surface of the singulated sheet.
However, the expandable particles SG may not necessarily be dispersed in at least one of the base material (Y) and the pressure-sensitive adhesive layer (X1). For example, the expandable particles SG may be located at a position corresponding to the division starting point of the adherend. May be arranged. In this case, even when energy is applied collectively to the entire surface of the singulated sheet, the force applied in the shear direction of the adherend acts locally only at the lower part of the division starting point of the adherend. However, it is possible to separate the adherend. Of course, when energy is applied to a part of the singulated sheet, only a part of the adherend can be singulated.

  Examples of the singulated sheet of the present invention include first to fifth embodiments described below.

<Individualized sheet of the first embodiment>
As the individualized sheet of the first aspect of the present invention, for example, as shown in FIG. 1, the base material (Y) has a non-expandable base material layer (Y2), and the non-expandable base material layer (Y2 ) Is an individualized sheet 1a in which an expandable pressure-sensitive adhesive layer (X1-1) containing expandable particles is laminated.

<Individualized sheet of the second embodiment>
As the individualized sheet of the second aspect of the present invention, for example, as shown in FIG. 2, the base material (Y) has an expandable base material layer (Y1) containing expandable particles, The individualized sheet 1b in which the non-expandable pressure-sensitive adhesive layer (X1-2) is laminated on the layer (Y1) is exemplified.
Here, in the case of the individualized sheet of the first embodiment, in the intumescent pressure-sensitive adhesive layer (X1-1), the expansion of the intumescent particles causes leakage of the inclusion components and the like in the intumescent particles, which is caused by this. The adhesive strength may be reduced. On the other hand, in the case of the singulated sheet according to the second aspect, in the non-expandable pressure-sensitive adhesive layer (X1-2), leakage of the encapsulated components and the like in the expandable particles due to expansion of the expandable particles does not occur. No decrease in adhesive strength due to the above-mentioned occurs. For this reason, when the energy is divided into two times as in the method for separating the adherend shown in FIGS. 5A and 5B described above, the second energy is applied as well as the first energy application. Even when energy is applied, a force in the shear direction can be applied to the adherend while the adherend is securely supported. In addition, the convex portions formed on the surface of the expandable base material layer (Y1) on the side of the non-expandable pressure-sensitive adhesive layer (X1-2) due to the expansion of the expandable particles form the non-expandable pressure-sensitive adhesive layer (X1-2). Contact the adherend through Therefore, as compared with the case where the expandable pressure-sensitive adhesive layer (X1-1) is expanded to apply a force in the shear direction to the adherend as in the individualized sheet of the first embodiment, The applied force can be gently transmitted to the adherend, and individual pieces are less likely to break. From such a viewpoint, the individualized sheet of the second embodiment is more preferable.

<Individualized sheet of the third embodiment>
As the individualized sheet of the third embodiment of the present invention, for example, as shown in FIG. 3, the base material (Y) has an expandable base material layer (Y1) containing expandable particles, An individualized sheet 1c in which the layer (Y1) is laminated with the expandable pressure-sensitive adhesive layer (X1-1) containing expandable particles is exemplified.
In the individualized sheet of the third aspect, both the expandable base material layer (Y1) and the expandable pressure-sensitive adhesive layer (X1-1) expand. For this reason, the expandable particles necessary for applying a force to generate a crack that starts at the division starting point of the adherend are formed by combining the expandable base material layer (Y1) and the expandable pressure-sensitive adhesive layer (X1-1). What is necessary is just to secure in both layers, the content of the expandable particles in the expandable pressure-sensitive adhesive layer (X1-1) is reduced, and the expandable pressure-sensitive adhesive layer (X1- It is easy to suppress the decrease in the adhesive force of 1). In the individualized sheet of the third aspect, the expansion of the expandable particles in the expandable base material layer (Y1) and the expansion of the expandable particles in the expandable pressure-sensitive adhesive layer (X1-1) overlap. Thereby, a large convex portion is easily generated on the surface of the expandable pressure-sensitive adhesive layer (X1-1). As a result, the distance by which the adherend WF is displaced in the shear direction can be increased, and a crack is likely to be formed at the division start point of the adherend.

  Here, when the base material (Y) has an expandable base material layer (Y1) containing expandable particles as in the individualized sheet of the second embodiment and the individualized sheet of the third embodiment, the expandable particles From the viewpoint of more efficiently generating a convex portion on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer (X1) by the expansion of the pressure-sensitive adhesive layer and easily applying a force for generating a crack starting from the division starting point of the adherend, the following is shown. The individualized sheet of the fourth aspect or the individualized sheet of the fifth aspect is preferred.

<Individualized sheets of the fourth and fifth aspects>
As the individualized sheet of the fourth embodiment of the present invention, for example, as shown in FIG. 4 (A), the base material (Y) includes an expandable base material (Y1) containing expandable particles and a non-expandable base material. An individualized sheet 1d having (Y2) and having a non-expandable pressure-sensitive adhesive layer (X1-2) laminated on an expansive base material (Y1).
Further, as the individualized sheet of the fifth aspect of the present invention, for example, as shown in FIG. 4 (B), the base material (Y) includes an expandable base material (Y1) containing expandable particles and a non-expandable base material. An individualized sheet 1e having the base material (Y2) and having the expandable pressure-sensitive adhesive layer (X1-1) laminated on the expandable base material (Y1) is given.
When the base material (Y) has the expandable base material (Y1) containing the expandable particles and the non-expandable base material (Y2), when a predetermined energy is applied to the individualized sheet, the expandable base material layer is formed. The expandable particles contained in (Y1) expand, and a convex portion is formed on the surface of the expandable base material layer (Y1) on the side of the pressure-sensitive adhesive layer (X1). Protrusions also occur on the surface. On the other hand, the non-expandable base material layer (Y2) is not easily deformed, and even if the expandable particles contained in the expandable base material layer (Y1) expand, the non-expandable base material Protrusions hardly occur on the surface on the base material layer (Y2) side. Therefore, due to the expansion of the expandable particles, the convex portion is predominantly formed on the surface of the expandable base material layer (Y1) on the side of the pressure-sensitive adhesive layer (X1), and following the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer (X1). Also, the convex portions are efficiently formed. Therefore, by applying a predetermined energy to a part of the singulated sheet, a part of the adherend adhered to the singulated sheet is easily displaced in the shearing direction, and the division starting point of the adherend is determined. Cracks are easily formed.
The singulated sheet according to the fourth aspect is the singulated sheet according to the second aspect, wherein the base material (Y) includes an expandable base material (Y1) containing expandable particles and a non-expandable base material (Y2). , The adhesive force of the non-expandable pressure-sensitive adhesive layer (X1-2) does not decrease due to leakage of the inclusion components and the like in the expandable particles.
The singulated sheet according to the fifth aspect is the singulated sheet according to the third aspect, wherein the base material (Y) includes an expandable base material (Y1) containing expandable particles and a non-expandable base material (Y2). , The content of the expandable particles in the expandable pressure-sensitive adhesive layer (X1-1) can be reduced, and the expandable pressure-sensitive adhesive layer due to leakage of the inclusion components and the like in the expandable pressure-sensitive adhesive layer (X1-1). It is easy to suppress the decrease in the adhesive strength of (X1-1). In addition, the distance by which the adherend WF is displaced in the shear direction can be increased, and a crack that starts at the division start point of the adherend can easily occur.

<Double-sided adhesive individualized sheet>
The singulated sheet according to one embodiment of the present invention is a double-sided pressure-sensitive singulated sheet having a configuration in which a substrate (Y) is sandwiched between an adhesive layer (X1) and another adhesive layer (X2). It may be.
As described above, by adopting a configuration having another pressure-sensitive adhesive layer (X2), when the adherend is singulated, the other pressure-sensitive adhesive layer (X2) is formed on a rigid support such as an iron plate or a glass plate. By sticking, the individualized sheet can be stably supported.
The other pressure-sensitive adhesive layer (X2) is a non-expandable pressure-sensitive adhesive layer. Further, like the singulated sheet of the fourth embodiment and the singulated sheet of the fifth embodiment, another pressure-sensitive adhesive layer (X2) is provided on the surface of the non-expandable base material layer (Y2) of the base material (Y). By sticking, it is possible to suppress the occurrence of convex portions on the other pressure-sensitive adhesive layer (X2) due to the expansion of the expandable base material (Y1), and to apply the adherend while applying energy to the individualized sheet. It can be stably supported.

<Individualized sheet provided with adhesive layer (Z)>
The individualized sheet of one embodiment of the present invention may have a stacked structure in which the base material (Y), the pressure-sensitive adhesive layer (X1), and the adhesive layer (Z) are stacked in this order. By adopting such a configuration, the adherend is attached to the adhesive layer (Z), and the adherend is singulated, whereby the adherend to which the adhesive layer (Z) is attached is singulated. be able to.

[Expandable particles]
The expandable particles are not particularly limited as long as they are particles that expand when given energy is applied thereto.An outer shell made of a thermoplastic resin, and a predetermined energy contained in the outer shell are applied. In this case, it is preferable to use a microencapsulated foaming agent that is composed of an internal component that expands due to vaporization or the like.

  Examples of the thermoplastic resin constituting the outer shell of the microencapsulated foaming agent include, for example, vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone. .

The internal component included in the outer shell is not particularly limited as long as it expands due to vaporization or the like when given energy is applied. For example, propane, butane, pentane, hexane, heptane, octane, nonane, decane, isobutane, isopentane, isohexane, isoheptane, isooctane, isononane, isodecane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, neopentane, Dodecane, isododecane, cyclotridecane, hexylcyclohexane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nanodecane, isotridecane, 4-methyldodecane, isotetradecane, isopentadecane, isohexadecane, 2,2,4,4,6 , 8,8-Heptamethylnonane, isoheptadecane, isooctadecane, isonanodecane, 2,6,10,14-tetramethylpe Tadekan, cyclotridecane, heptyl cyclohexane, n- octyl cyclohexane, cyclopentadecane, nonyl cyclohexane, decyl cyclohexane, pentadecyl cyclohexane, hexadecyl cyclohexane, heptadecyl cyclohexane, octadecyl cyclohexane.
These inclusion components may be used alone or in combination of two or more.

Examples of the predetermined energy for expanding the expandable particles include heat, infrared light, ultraviolet light, visible light, sound waves, X-rays, and gamma rays. The type of the predetermined energy for expanding the expandable particles can be selected, for example, by appropriately selecting the type of the inclusion component.
Further, by appropriately selecting the type of the inclusion component, the value of the predetermined energy used for expanding the expandable particles can be adjusted. For example, when the expandable particles are heat expandable particles that expand due to heat, the expansion start temperature of the heat expandable particles can be adjusted by appropriately selecting the type of the inclusion component. When the expandable particles are infrared expandable particles that expand due to infrared light, the intensity of the infrared light for expanding the infrared expandable particles can be adjusted by appropriately selecting the type of the inclusion component.

Here, in the individualized sheet of one embodiment of the present invention, two or more types of expandable particles may be contained.
For example, the expandable particles may include first expandable particles that expand at a predetermined first energy and second expandable particles that expand at a second energy different from the first energy.
Here, the “second energy different from the first energy” includes both the case where the energy type for expanding the expandable particles is different and the case where the energy value for expanding the expandable particles is different. Meaning.
Examples of the combination of the first energy and the second energy include two types selected from heat, infrared rays, ultraviolet rays, visible light rays, sound waves, X-rays, and gamma rays. Alternatively, combinations of different types of energy required for expansion for one selected from these are listed. For example, a combination of two types of thermally expandable particles having different expanding temperature ranges, a combination of two types of infrared expandable particles having different expanding infrared intensities, and the like can be given.

  The volume maximum expansion rate of the expandable particles is preferably 5 to 500 times, more preferably 10 to 250 times, and still more preferably 30 to 100 times.

The average particle size of the expandable particles before expansion at 23 ° C. is preferably 3 to 100 μm, more preferably 4 to 70 μm, further preferably 6 to 60 μm, and still more preferably 10 to 50 μm.
The average particle size of the expandable particles is a volume median particle size (D ₅₀ ), which is measured using a laser diffraction particle size distribution analyzer (for example, product name “Master Sizer 3000” manufactured by Malvern). Means the particle size corresponding to 50% of the cumulative volume frequency calculated from the smaller particle size of the expandable particles in the obtained particle distribution of the expandable particles.

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, further preferably 25 to ₉₀ μm, and still more preferably 30 to 80 μm. .
The 90% particle diameter (D ₉₀ ) of the expandable particles refers to the particle size distribution of the expandable particles measured using a laser diffraction type particle size distribution analyzer (for example, product name “Master Sizer 3000” manufactured by Malvern). , The cumulative volume frequency calculated from the smaller particle size of the expandable particles corresponds to 90%.

[Base material (Y)]
The substrate (Y) of the singulated sheet of the present invention has at least one of an expandable substrate layer (Y1) containing expandable particles and a non-expandable substrate layer (Y2).
That is, the base material (Y) may have an inflatable base material layer (Y1), for example, like the individualized sheet 1b shown in FIG. 2 and the individualized sheet 1c shown in FIG. .
Further, the base material (Y) may have a non-expandable base material layer (Y2), for example, like the individualized sheet 1a shown in FIG.
Further, the base material (Y) and the singulated sheet 1d shown in FIG. 4A and the singulated sheet 1e shown in FIG. It may have an expandable base material (Y2). In this case, the expandable base material layer (Y1) and the non-expandable base material layer (Y2) may be bonded with an adhesive. Thereby, the interlayer adhesion between the expandable base material layer (Y1) and the non-expandable base material layer (Y2) can be improved. The adhesive is not particularly limited, and can be formed from a general adhesive or a pressure-sensitive adhesive composition that is a material for forming the pressure-sensitive adhesive layer (X1) and another pressure-sensitive adhesive layer (X2).

Here, in one embodiment of the present invention, for example, as in the individualized sheets 1d and 1e shown in FIGS. 4A and 4B, the base material (Y) is a laminated surface of the pressure-sensitive adhesive layer (X1). It is preferable that the non-expandable base material layer (Y2) is laminated on the surface opposite to the surface on which the pressure-sensitive adhesive layer (X1) is laminated, having the expandable base material layer (Y1) on the side.
In this case, when predetermined energy is applied to the individualized sheet, the expandable particles contained in the expandable base material layer (Y1) expand, and the pressure-sensitive adhesive layer (X1) of the expandable base material layer (Y1) is expanded. A convex portion is formed on the surface on the side, and a convex portion is also formed on the adhesive surface of the pressure-sensitive adhesive layer (X1). On the other hand, the non-expandable base material layer (Y2) is difficult to deform, and even if the expandable particles contained in the expandable base material layer (Y1) expand, the non-expandable base Protrusions hardly occur on the surface on the material layer (Y2) side. As a result, convex portions are likely to be predominantly formed on the surface of the expandable base material layer (Y1) on the side of the adhesive layer (X1), and the convex portions are efficiently formed on the adhesive surface of the adhesive layer (X1). It is formed. Therefore, by applying a predetermined energy to a part of the singulated sheet, a part of the adherend adhered to the singulated sheet is easily displaced in the shearing direction, and the division starting point of the adherend is determined. Cracks are easily formed.

In addition, both the expandable base material layer (Y1) and the non-expandable base material layer (Y2) constituting the base material (Y) are non-adhesive layers.
In the present invention, the determination as to whether or not the layer is a non-adhesive layer is made when the probe tack value measured in accordance with JIS Z0237: 1991 with respect to the surface of the target layer is less than 50 mN / 5 mmφ. The layer is determined to be a “non-stick layer”.
Although the probe tack value on the surface of the expandable base material layer (Y1) and the surface of the non-expandable base material layer (Y2) included in the singulated sheet of one embodiment of the present invention are each independently usually less than 50 mN / 5 mmφ. , Preferably less than 30 mN / 5 mmφ, more preferably less than 10 mN / 5 mmφ, and even more preferably less than 5 mN / 5 mmφ.
In the present specification, a specific method for measuring the probe tack value on the surfaces of the expandable base material (Y1) and the non-expandable base material (Y2) is based on the method described in Examples.

  In the individualized sheet of one embodiment of the present invention, the thickness of the substrate (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. It is.

Before the expansion of the expandable particles, the thickness of the expandable base material layer (Y1) is preferably 10 to 1000 μm, more preferably 20 to 700 μm, further preferably 25 to 500 μm, and still more preferably 30 to 300 μm. .
The thickness of the non-expandable base material layer (Y2) is preferably from 10 to 1000 μm, more preferably from 20 to 700 μm, further preferably from 25 to 500 μm, and still more preferably from 30 to 300 μm.

  In the individualized sheet of one embodiment of the present invention, the thickness ratio of the expandable base material layer (Y1) to the non-thermally expandable base material layer (Y2) before the expansion of the expandable particles [(Y1) / (Y2)] is preferably 0.02 to 200, more preferably 0.03 to 150, and still more preferably 0.05 to 100.

  In the singulated sheet of one embodiment of the present invention, the expandable base material layer (Y1) before the expansion of the expandable particles, and the pressure-sensitive adhesive layer (X1) directly laminated on the expandable base material layer (Y1). The thickness ratio [(Y1) / (X1)] is preferably 0.2 or more, more preferably 0.5 or more, further preferably 1.0 or more, and still more preferably 5.0 or more, Further, it is preferably 1,000 or less, more preferably 200 or less, still more preferably 60 or less, and still more preferably 30 or less.

  In the individualized sheet of one embodiment of the present invention, the thickness ratio of the non-expandable base material layer (Y2) to another pressure-sensitive adhesive layer (X2) directly laminated on the non-expandable base material layer (Y2) [(Y2) / (X2)] is preferably 0.1 or more, more preferably 0.2 or more, further preferably 0.3 or more, and preferably 20 or less, more preferably 10 or less. More preferably, it is 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.

<Expandable base material layer (Y1)>
The expandable base material layer (Y1) is a base material layer that contains expandable particles and can be expanded by an expansion treatment that applies predetermined energy to the expandable particles.
The content of the expandable particles in the expandable base material layer (Y1) is preferably 1 to 40% by mass, more preferably 5% by mass, based on the total mass (100% by mass) of the expandable base material layer (Y1). It is preferably from 35 to 35% by mass, more preferably from 10 to 30% by mass, even more preferably from 15 to 25% by mass.

In addition, from the viewpoint of improving the interlayer adhesion between the expandable base material layer (Y1) and other layers to be laminated, the surface of the expandable base material layer (Y1) is subjected to an oxidation method, a surface roughening method, or the like. Treatment, easy adhesion treatment, or primer treatment may be performed.
Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromic acid treatment (wet method), hot air treatment, ozone, and ultraviolet irradiation treatment. Examples of the unevenness method include a sand blast method and a solvent treatment method. And the like.

In one embodiment of the present invention, the expandable base material layer (Y1) more preferably satisfies the following requirement (1).
-Requirement (1): The storage elastic modulus E '(t) of the expandable base material layer (Y1) at the temperature (t) at the start of expansion of the expandable particles is 1.0 × 10 ⁷ Pa or less.
For example, when the expandable particles are thermally expandable particles, the “temperature (t) at the start of expansion of the expandable particles” means “the expansion start temperature of the thermally expandable particles”. For example, if the expansion start temperature is 100 ° C., the “temperature (t) at the start of expansion of the expandable particles” is 100 ° C. When the expandable particles are thermally expandable particles, it is preferable that the expansion start temperature (t) is 60 to 270 ° C.
In addition, for example, in the case of an expandable particle such as an infrared expandable particle that starts expanding at room temperature (23 ° C.) by infrared irradiation, the “temperature (t) at the start of expansion of the expandable particle” is room temperature (23 ° C.). It is.
In the present specification, the storage elastic modulus E ′ (t) of the expandable base material layer (Y1) at a predetermined temperature means a value measured by the method described in Examples.

The requirement (1) can be said to be an index indicating the rigidity of the expandable base material layer (Y1) immediately before the expandable particles expand.
That is, when the expandable particles expand, if the expandable base material layer (Y1) has flexibility to the extent that the requirement (1) is satisfied, the surface of the expandable base material layer (Y1) is convex. A part is easily formed, and a convex part is also easily formed on the adhesive surface of the adhesive layer (X1). As a result, by applying a predetermined energy to a part of the singulated sheet, a part of the adherend adhered to the singulated sheet is easily displaced in the shear direction, and the starting point of division of the adherend Cracks are likely to occur.

From the above viewpoint, the storage elastic modulus E ′ (t) defined by the above requirement (1) is preferably 9.0 × 10 ⁶ Pa or less, more preferably 8.0 × 10 ⁶ Pa or less, and further more preferably 6.0 × 10 ⁶ Pa or less. The pressure is 0 × 10 ⁶ Pa or less, more preferably 4.0 × 10 ⁶ Pa or less.
In addition, it suppresses the flow of the expanded expandable particles, improves the shape retention of the convex portion generated on the surface of the expandable base material layer (Y1), and further generates a convex portion on the adhesive surface of the adhesive layer (X1). From the viewpoint of facilitation, the storage elastic modulus E ′ (t) defined by the requirement (1) is preferably 1.0 × 10 ³ Pa or more, more preferably 1.0 × 10 ⁴ Pa or more, and still more preferably 1 × 10 ⁴ Pa or more. 0.010 ⁵ Pa or more.

(Method of measuring the expansion start temperature of thermally expandable particles)
When heat-expandable particles are used as the expandable particles, the measurement of the expansion start temperature of the heat-expandable particles is performed by the method described below.
To an aluminum cup having a diameter of 6.0 mm (5.65 mm inner diameter) and a depth of 4.8 mm, 0.5 mg of the thermally expandable particles to be measured are added, and an aluminum lid (5.6 mm in diameter, 0.3 mm in thickness) is placed on the aluminum cup. 1 mm) is prepared.
Using a dynamic viscoelasticity measuring apparatus, the height of the sample is measured from the upper part of the aluminum lid while a force of 0.01 N is applied to the sample by a pressurizer. Then, with the force of 0.01 N applied by the pressurizer, the heater is heated from 20 ° C. to 300 ° C. at a rate of 10 ° C./min, and the displacement of the pressurizer in the vertical direction is measured. The displacement start temperature is defined as the expansion start temperature.

(Resin composition (y))
The expandable base material layer (Y1) is preferably formed from a resin composition (y) containing a resin and expandable particles.
In addition, the resin composition (y) may contain an additive for a base material, if necessary, as long as the effects of the present invention are not impaired.
Examples of the base additive include an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a slip agent, an antiblocking agent, and a coloring agent.
In addition, these additives for base materials may be used individually by 1 type, and may be used in combination of 2 or more types.
When containing these base material additives, the content of each base material additive is preferably from 0.0001 to 20 parts by mass, more preferably from 0.001 to 20 parts by mass, based on 100 parts by mass of the resin. 10 parts by mass.

  The content of the expandable particles is preferably 1 to 40% by mass, more preferably 5 to 35% by mass, and still more preferably 10 to 10% by mass based on the total amount (100% by mass) of the active ingredient of the resin composition (y). It is 30% by mass, more preferably 15 to 25% by mass.

The resin contained in the resin composition (y) that is the material for forming the expandable base material layer (Y1) may be a non-adhesive resin or an adhesive resin.
That is, 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 becomes a polymerizable compound. And the resulting resin becomes a non-adhesive resin, and the expandable base material layer (Y1) containing the resin becomes non-adhesive.

The weight average molecular weight (Mw) of the resin contained in the resin composition (y) is preferably 1,000 to 1,000,000, more preferably 1,000 to 700,000, and still more preferably 1,000 to 500,000.
When the resin is a copolymer having two or more types of 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. It may be.

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

In one embodiment of the present invention, from the viewpoint of forming an expandable base material layer (Y1) in which convex portions are likely to be generated on the surface when the expandable particles expand, the resin contained in the resin composition (y) is acrylic urethane. It is preferable to include at least one selected from a series resin and an olefin resin.
Further, as the acrylic urethane-based resin, an acrylic urethane-based resin (U1) obtained by polymerizing a urethane prepolymer (UP) and a vinyl compound containing a (meth) acrylate is preferable.

(Acrylic urethane resin (U1))
Examples of the urethane prepolymer (UP) serving as the main chain of the acrylic urethane-based resin (U1) include a reaction product of a polyol and a polyvalent isocyanate.
The urethane prepolymer (UP) is preferably obtained by further performing a chain extension reaction using a chain extender.

Examples of the polyol serving as a raw material of the urethane prepolymer (UP) include an alkylene type polyol, an ether type polyol, an ester type polyol, an ester amide type polyol, an ester ether type polyol, and a carbonate type polyol.
These polyols may be used alone or in combination of two or more.
The polyol used in one embodiment of the present invention is preferably a diol, more preferably an ester diol, an alkylene diol, or a carbonate diol, and further preferably an ester diol or a carbonate diol.

Examples of the ester type diol include alkane diols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, and 1,6-hexanediol; ethylene glycol, propylene glycol, One or more diols such as alkylene glycols such as diethylene glycol and dipropylene glycol; and phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, and diphenylmethane-4. , 4'-dicarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, heptic acid, maleic acid, fumaric acid, itaconic acid, cyclohexane-1,3-dicarboxylic acid, cyclohexane-1,4-dicarboxylic acid, hexa Hydrophthalic acid, Condensed polymers of dicarboxylic acids such as hexahydroisophthalic acid, hexahydroterephthalic acid, methylhexahydrophthalic acid, and one or more selected from anhydrides thereof are exemplified.
Specifically, polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polyhexamethylene isophthalate diol, polyneopentyl adipate diol, polyethylene propylene adipate diol, polyethylene butylene adipate diol, polybutylene hexamethylene adipate diol, Polydiethylene adipate diol, poly (polytetramethylene ether) adipate diol, poly (3-methylpentylene adipate) diol, polyethylene azelate diol, polyethylene sebacate diol, polybutylene azelate diol, polybutylene sebacate diol and polyneo And pentyl terephthalate diol.

  Examples of the alkylene type diol include alkane diols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, and 1,6-hexanediol; ethylene glycol, propylene glycol, Alkylene glycols such as diethylene glycol and dipropylene glycol; polyalkylene glycols such as polyethylene glycol, polypropylene glycol and polybutylene glycol; polyoxyalkylene glycols such as polytetramethylene glycol;

  Examples of the carbonate type diol include 1,4-tetramethylene carbonate diol, 1,5-pentamethylene carbonate diol, 1,6-hexamethylene carbonate diol, 1,2-propylene carbonate diol, and 1,3-propylene carbonate diol. , 2,2-dimethylpropylene carbonate diol, 1,7-heptamethylene carbonate diol, 1,8-octamethylene carbonate diol, 1,4-cyclohexane carbonate diol, and the like.

Examples of the polyvalent isocyanate serving as a raw material of the urethane prepolymer (UP) include an aromatic polyisocyanate, an aliphatic polyisocyanate, and an alicyclic polyisocyanate.
These polyvalent isocyanates may be used alone or in combination of two or more.
These polyvalent isocyanates may be a modified trimethylolpropane adduct, a modified buret reacted with water, or a modified isocyanurate containing an isocyanurate ring.

  Among these, as the polyvalent isocyanate used in one embodiment of the present invention, diisocyanate is preferable, and 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2,6 -One or more selected from tolylene diisocyanate (2,6-TDI), hexamethylene diisocyanate (HMDI), and alicyclic diisocyanate are more preferable.

  Examples of the alicyclic diisocyanate include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, and 1,4-cyclohexane. Examples thereof include diisocyanate, methyl-2,4-cyclohexane diisocyanate, and methyl-2,6-cyclohexane diisocyanate, and isophorone diisocyanate (IPDI) is preferable.

In one embodiment of the present invention, the urethane prepolymer (UP) serving as the main chain of the acrylic urethane-based resin (U1) is a reaction product of a diol and a diisocyanate, and has a straight chain having an ethylenically unsaturated group at both terminals. Urethane prepolymers are preferred.
As a method for introducing an ethylenically unsaturated group into both terminals of the linear urethane prepolymer, a NCO group at a terminal of the linear urethane prepolymer obtained by reacting a diol with a diisocyanate compound, and a hydroxyalkyl (meth) acrylate And a method of reacting

  Examples of the hydroxyalkyl (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 3-hydroxy. Butyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and the like.

The vinyl compound serving as a side chain of the acrylic urethane resin (U1) contains at least a (meth) acrylate.
As the (meth) acrylate, at least one selected from alkyl (meth) acrylate and hydroxyalkyl (meth) acrylate is preferable, and it is more preferable to use alkyl (meth) acrylate and hydroxyalkyl (meth) acrylate together.

  When the alkyl (meth) acrylate and the hydroxyalkyl (meth) acrylate are used in combination, the mixing ratio of the hydroxyalkyl (meth) acrylate to 100 parts by mass of the alkyl (meth) acrylate is preferably 0.1 to 100 parts by mass, Preferably it is 0.5 to 30 parts by mass, more preferably 1.0 to 20 parts by mass, even more preferably 1.5 to 10 parts by mass.

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

  Examples of the hydroxyalkyl (meth) acrylate include the same hydroxyalkyl (meth) acrylate used to introduce an ethylenically unsaturated group into both ends of the above-mentioned linear urethane prepolymer.

Examples of vinyl compounds other than (meth) acrylic acid esters include, for example, aromatic hydrocarbon vinyl compounds such as styrene, α-methylstyrene and vinyltoluene; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; vinyl acetate and vinyl propionate , (Meth) acrylonitrile, N-vinylpyrrolidone, polar group-containing monomers such as (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, and meth (acrylamide).
These may be used alone or in combination of two or more.

  The content of the (meth) acrylic acid ester in the vinyl compound is preferably 40 to 100% by mass, more preferably 65 to 100% by mass, and still more preferably the total amount (100% by mass) of the vinyl compound. It is 80 to 100% by mass, more preferably 90 to 100% by mass.

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

  In the acrylic urethane resin (U1) used in one embodiment of the present invention, the content ratio of the structural unit (u11) derived from the urethane prepolymer (UP) and the structural unit (u12) derived from the vinyl compound [(u11 ) / (U12)] is preferably 10/90 to 80/20, more preferably 20/80 to 70/30, still more preferably 30/70 to 60/40, and even more preferably 35 by mass ratio. / 65-55 / 45.

(Olefin resin)
Examples of the olefin-based resin suitable as the resin contained in the resin composition (y) include a polymer having at least a structural unit derived from an olefin monomer.
As the olefin monomer, an α-olefin having 2 to 8 carbon atoms is preferable, and specific examples include ethylene, propylene, butylene, isobutylene, and 1-hexene.
Among these, ethylene and propylene are preferred.

Specific olefinic resins, for example, ultra low density polyethylene (VLDPE, density: 880 kg / ^{m 3} or more 910 kg / ^m less than ^3), low density polyethylene (LDPE, density: 910 kg / ^{m 3} or more 915 kg / ^m less than ³ ), Medium density polyethylene (MDPE, density: 915 kg / m ³ or more and less than 942 kg / m ³ ), high density polyethylene (HDPE, density: 942 kg / m ³ or more), polyethylene resin such as linear low density polyethylene; polypropylene resin (PP); polybutene resin (PB); ethylene-propylene copolymer; olefin-based elastomer (TPO); ethylene-vinyl acetate copolymer (EVA); ethylene-propylene- (5-ethylidene-2-norbornene) and the like. Olefin terpolymer; and the like.

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

For example, as the acid-modified olefin resin obtained by subjecting the olefin resin to acid modification, a modified polymer obtained by graft-polymerizing an unsaturated carboxylic acid or an anhydride thereof with the above-mentioned unmodified olefin resin. Is mentioned.
Examples of the above unsaturated carboxylic acid or anhydride thereof include maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaconic acid, tetrahydrophthalic acid, aconitic acid, (meth) acrylic acid, maleic anhydride, and itaconic anhydride , Glutaconic anhydride, citraconic anhydride, aconitic anhydride, norbornene dicarboxylic anhydride, tetrahydrophthalic anhydride and the like.
The unsaturated carboxylic acids or their anhydrides may be used alone or in combination of two or more.

The acrylic-modified olefin-based resin obtained by subjecting the olefin-based resin to an acrylic modification is a modification obtained by graft-polymerizing an alkyl (meth) acrylate as a side chain to the above-mentioned unmodified olefin-based resin as a main chain. Polymers.
The number of carbon atoms of the alkyl group of the alkyl (meth) acrylate is preferably 1 to 20, more preferably 1 to 16, and further preferably 1 to 12.
Examples of the above-mentioned alkyl (meth) acrylate include the same compounds as the compounds that can be selected as the monomer (a1 ′) described below.

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

(Resins other than acrylic urethane resin and olefin resin)
In one embodiment of the present invention, the resin composition (y) may contain a resin other than the acrylic urethane resin and the olefin resin, as long as the effects of the present invention are not impaired.
Examples of such a resin include vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer; polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalene. Polyester resin such as phthalate; polystyrene; acrylonitrile-butadiene-styrene copolymer; cellulose triacetate; polycarbonate; polyurethane not applicable to acrylic urethane resin; polymethylpentene; polysulfone; polyetheretherketone; polyethersulfone; Sulfides; polyimide resins such as polyetherimide and polyimide; polyamide resins; acrylic resins;

However, the resin composition (y) contains a resin other than the acrylic urethane-based resin and the olefin-based resin from the viewpoint of forming the expandable base material layer (Y1) in which convex portions are likely to be generated on the surface when the expandable particles expand. The smaller the ratio, the better.
The content ratio of the resin other than the acrylic urethane-based resin and the olefin-based resin is preferably less than 30 parts by mass, more preferably 20 parts by mass, based on 100 parts by mass of the total amount of the resin contained in the resin composition (y). Less than 10 parts by weight, more preferably less than 5 parts by weight, even more preferably less than 1 part by weight.

(Solvent-free resin composition (y1))
As one embodiment of the resin composition (y), an oligomer having an ethylenically unsaturated group having a mass average molecular weight (Mw) of 50,000 or less, an energy ray polymerizable monomer, and the above-described heat-expandable particles are blended. A solvent-free resin composition (y1) containing no solvent is exemplified.
In the solvent-free resin composition (y1), a solvent is not blended, but the energy ray-polymerizable monomer contributes to improvement of the plasticity of the oligomer.
By irradiating the coating film formed from the solvent-free resin composition (y1) with an energy ray, an intumescent base material layer (Y1) in which a convex portion is easily generated on the surface when the intumescent particles expand is formed. In particular, it is easy to form the expandable base material layer (Y1) satisfying the above requirement (1).

  In addition, about the kind, shape, and compounding quantity (content) of the expandable particle mix | blended with the solventless resin composition (y1), it is the same as that of the resin composition (y), and is as above-mentioned.

  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, still more preferably 3,000 to 35,000, More preferably, it is 4000 to 30,000.

As the oligomer, any resin having an ethylenically unsaturated group having a mass average molecular weight of 50,000 or less among the resins contained in the above resin composition (y) may be used, but the urethane prepolymer (UP) Is preferred.
In addition, a modified olefin-based resin having an ethylenically unsaturated group may be used as the oligomer.

  The total content of the oligomer and the energy ray-polymerizable monomer in the solvent-free resin composition (y1) is preferably 50 to 50% based on the total amount (100% by mass) of the solvent-free resin composition (y1). It is 99% by mass, more preferably 60 to 95% by mass, still more preferably 65 to 90% by mass, and still more preferably 70 to 85% by mass.

Examples of the energy beam polymerizable monomer include isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyloxy (meth) acrylate, cyclohexyl (meth) acrylate, and adamantane ( Alicyclic polymerizable compounds such as meth) acrylate and tricyclodecane acrylate; aromatic polymerizable compounds such as phenylhydroxypropyl acrylate, benzyl acrylate and phenol ethylene oxide-modified acrylate; tetrahydrofurfuryl (meth) acrylate, morpholine acrylate, N- Heterocyclic polymerizable compounds such as vinylpyrrolidone and N-vinylcaprolactam.
These energy ray polymerizable monomers may be used alone or in combination of two or more.

  The compounding ratio of the oligomer and the energy ray-polymerizable monomer (the oligomer / the energy ray-polymerizable monomer) is preferably 20/80 to 90/10, more preferably 30/70 to 85/15, and still more preferably 35/65. ８０80/20.

In one embodiment of the present invention, the solvent-free resin composition (y1) preferably further contains a photopolymerization initiator.
By containing the photopolymerization initiator, the curing reaction can be sufficiently advanced even by irradiation with relatively low energy energy rays.

Examples of the photopolymerization initiator include 1-hydroxy-cyclohexyl-phenyl-ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzyl phenyl sulfide, tetramethyl thiuram monosulfide, and azobisisobutyrol Examples include nitrile, dibenzyl, diacetyl, 8-chloranthraquinone and the like.
One of these photopolymerization initiators may be used alone, or two or more thereof may be used in combination.

  The amount of the photopolymerization initiator is preferably 0.01 to 5 parts by mass, more preferably 0.01 to 4 parts by mass, based on the total amount (100 parts by mass) of the oligomer and the energy ray-polymerizable monomer. Preferably it is 0.02 to 3 parts by mass.

<Non-expandable base material layer (Y2)>
Examples of the material for forming the non-expandable base material layer (Y2) include paper materials, resins, and metals.
Examples of the paper material include thin paper, medium quality paper, high quality paper, impregnated paper, coated paper, art paper, parchment paper, glassine 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; polyethylene terephthalate, Polyester resins such as butylene terephthalate and polyethylene naphthalate; polystyrene; acrylonitrile-butadiene-styrene copolymer; cellulose triacetate; polycarbonate; urethane resins such as polyurethane and acrylic-modified polyurethane; polymethylpentene; polysulfone; Polyether sulfone; Polyphenylene sulfide; Polyimide-based resin such as polyetherimide and polyimide; Polyamide-based resin; Acrylic resin; Tsu Motokei resin, and the like.
Examples of the metal include aluminum, tin, chromium, and titanium.

One of these forming materials may be used alone, or two or more thereof may be used in combination.
As the non-expandable base material layer (Y2) in which two or more kinds of forming materials are combined, a paper material laminated with a thermoplastic resin such as polyethylene, a resin film containing a resin or a metal sheet on the surface of a singulated sheet is used. One having a film formed thereon is exemplified.
In addition, as a method of forming the metal layer, for example, a method in which the metal is deposited by a PVD method such as vacuum evaporation, sputtering, or ion plating, or a metal foil made of the metal is attached using a general adhesive. And the like.

  In addition, from the viewpoint of improving the interlayer adhesion between the non-expandable base material layer (Y2) and another layer to be laminated, when the non-expandable base material layer (Y2) contains a resin, the non-expandable base material layer ( The surface of Y2) may be subjected to a surface treatment such as an oxidation method or a roughening method, an easy adhesion treatment, or a primer treatment as in the case of the above-described intumescent base material layer (Y1).

  When the non-expandable base material layer (Y2) contains a resin, the above-mentioned base material additive which may be contained in the resin composition (y) may be contained together with the resin.

The non-intumescent base material layer (Y2) is a non-intumescent layer determined based on the method described above.
Therefore, the volume change rate (%) of the non-expandable base material layer (Y2) calculated from the above equation is less than 5%, preferably less than 2%, more preferably less than 1%, and still more preferably. Is less than 0.1%, even more preferably less than 0.01%.

In addition, the non-expandable base material layer (Y2) may contain expandable particles as long as the volume change rate is within the above range. For example, by selecting a resin contained in the non-expandable base material layer (Y2), it is possible to adjust the volume change rate to the above-mentioned range even if heat-expandable particles are contained.
However, the content of the expandable particles in the non-expandable base material layer (Y2) is preferably as small as possible.
The specific content of the expandable particles is usually less than 3% by mass, preferably less than 1% by mass, more preferably 0% by mass based on the total mass (100% by mass) of the non-expandable base material layer (Y2). 0.1 mass%, more preferably less than 0.01 mass%, even more preferably less than 0.001 mass%.

Here, in one embodiment of the present invention, when the expandable particles contained in the expandable base material layer (Y1) expand, the expandable base material layer (Y1) is closer to the non-expandable base material layer (Y2). From the viewpoint of suppressing the formation of convex portions on the surface and forming the convex portions predominantly on the surface of the expandable base material layer (Y1) on the side of the pressure-sensitive adhesive layer (X1), the non-expandable base material The layer (Y2) preferably has such a rigidity that it is not deformed by expansion of the expandable particles. Specifically, the storage elastic modulus E ′ (t) of the non-expandable base material layer (Y2) at the temperature (t) at the time when the expansion of the expandable particles starts is 1.1 × 10 ⁷ Pa or more. Is preferred.

<Adhesive layer (X1), other adhesive layers (X2)>
The individualized sheet of the present invention has an adhesive layer (X1).
The individualized sheet of one embodiment of the present invention has another pressure-sensitive adhesive layer (X2).
An adherend is attached to the adhesive surface of the adhesive layer (X1), and a support is attached to the adhesive surface of the other adhesive layer (X2).
In the individualized sheet according to one embodiment of the present invention, the adhesive layer (Z) is laminated on the adhesive surface of the adhesive layer (X1).

The pressure-sensitive adhesive layer (X1) is required to have a property capable of sufficiently fixing the adherend before the expansion of the expandable particles contained in the expandable base material layer (Y1).
From this viewpoint, the storage shear modulus G ′ (23) of the pressure-sensitive adhesive layer (X1) at 23 ° C. is preferably 1.0 × 10 ⁴ Pa or more, more preferably 5.0 × 10 ⁴ Pa or more, and furthermore It is preferably at least 1.0 × 10 ⁵ Pa.
On the other hand, when the convex portions are generated by expanding the expandable base material layer (Y1), the surface of the expandable base material layer (Y1) is expanded when the expandable particles in the expandable base material layer (Y1) expand. Is also required to have such a rigidity that the protrusions formed on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer (X1) can be formed.
From this viewpoint, the storage shear modulus G ′ (23) of the pressure-sensitive 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 furthermore Preferably it is 1.0 × 10 ⁷ Pa or less.
In the present specification, the storage shear modulus G ′ (23) of the pressure-sensitive adhesive layer (X1) means a value measured by the method described in Examples.

The other pressure-sensitive adhesive layer (X2) preferably has a storage shear modulus G ′ (23) at 23 ° C. of 23 ° C. from the viewpoint of sufficiently securing fixation to the rigid support. Is at least 1.0 × 10 ⁴ Pa, more preferably at least 5.0 × 10 ⁴ Pa, even more preferably at least 1.0 × 10 ⁵ Pa.
However, when the non-expandable base material layer (Y2) was not provided between the expandable base material layer (Y1) and the other pressure-sensitive adhesive layer (X2), it occurred on the surface of the expandable base material layer (Y2). Rigidity is required to such an extent that no convex portion is formed on the adhesive surface of the other adhesive layer (X2). In this case, the storage shear modulus G ′ (23) of the other pressure-sensitive adhesive layer (X2) is preferably larger than 1.0 × 10 ⁷ Pa, more preferably larger than 5.0 × 10 ⁷ Pa. More preferably, it is more preferably larger than 1.0 × 10 ⁸ Pa.

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

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

The pressure-sensitive adhesive layer (X1) and another pressure-sensitive adhesive layer (X2) can be formed from a pressure-sensitive adhesive composition (x) containing a pressure-sensitive adhesive resin.
Further, the pressure-sensitive adhesive composition (x) may contain a pressure-sensitive adhesive additive such as a crosslinking agent, a tackifier, a polymerizable compound, and a polymerization initiator, if necessary.
When the pressure-sensitive adhesive layer (X1) is the expandable pressure-sensitive adhesive layer (X1-1) containing expandable particles, the pressure-sensitive adhesive composition (x) contains expandable particles.

  The content of the expandable particles is preferably 1 to 40% by mass, more preferably 5 to 35% by mass, and still more preferably 10% by mass, based on the total amount (100% by mass) of the active ingredients of the pressure-sensitive adhesive composition (x). To 30% by mass, and still more preferably 15 to 25% by mass.

  Hereinafter, each component contained in the pressure-sensitive adhesive composition (x) will be described.

(Adhesive resin)
The adhesive resin may be any polymer as long as the resin alone has adhesiveness and has a weight average molecular weight (Mw) of 10,000 or more.
The weight average molecular weight (Mw) of the adhesive resin used in one embodiment of the present invention is preferably 10,000 to 2,000,000, more preferably 20,000 to 1.5,000,000, and still more preferably 30,000, from the viewpoint of improving the adhesive strength. ~ 1,000,000.

Specific adhesive resins include, for example, rubber resins such as acrylic resins, urethane resins, and polyisobutylene resins, polyester resins, olefin resins, silicone resins, and polyvinyl ether resins.
One of these adhesive resins may be used alone, or two or more thereof may be used in combination.
When these adhesive resins are copolymers having two or more types of structural units, the form of the copolymer is not particularly limited, and may be a block copolymer, a random copolymer, or a graft copolymer. Any of polymers may be used.

The adhesive resin used in one embodiment of the present invention may be an energy-ray-curable adhesive resin having a polymerizable functional group introduced into a side chain of the adhesive resin.
For example, by forming the other pressure-sensitive adhesive layer (X2) from an energy-ray-curable pressure-sensitive adhesive composition containing an energy-ray-curable pressure-sensitive adhesive resin, the adhesive strength can be reduced by irradiating with energy rays. Therefore, after the individualization of the adherend is completed, the adhesive strength of the other adhesive layer (X2) is reduced, and the individualized sheet can be easily peeled from the support.
Examples of the polymerizable functional group include a (meth) acryloyl group and a vinyl group.
In addition, examples of the energy ray include an ultraviolet ray and an electron beam, and an ultraviolet ray is preferable.
The material for forming the pressure-sensitive adhesive layer that can reduce the adhesive strength by irradiation with energy rays may be an energy-ray-curable pressure-sensitive adhesive composition containing a monomer or oligomer having a polymerizable functional group.

It is preferable that these energy ray-curable pressure-sensitive adhesive compositions further contain a photopolymerization initiator.
By containing the photopolymerization initiator, the curing reaction can be sufficiently advanced even by irradiation with relatively low energy energy rays.
Examples of the photopolymerization initiator include the same ones as those compounded in the solventless resin composition (y1) described above.
The content of the photopolymerization initiator is preferably from 0.01 to 10 parts by mass, more preferably from 100 to 100 parts by mass of the energy ray-curable adhesive resin or the monomer or oligomer having a polymerizable functional group. It is 0.03 to 5 parts by mass, and more preferably 0.05 to 2 parts by mass.

  In one embodiment of the present invention, from the viewpoint of developing excellent adhesive strength, the adhesive resin preferably contains an acrylic resin. In particular, by forming the pressure-sensitive adhesive layer (X1) from a pressure-sensitive adhesive composition containing an acrylic resin, it is possible to easily form a convex portion on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer (X1).

  The content of the acrylic resin in the adhesive resin is preferably 30 to 100% by mass, more preferably 50 to 100% by mass, based on the total amount (100% by mass) of the adhesive resin contained in the adhesive composition (x). -100% by mass, more preferably 70-100% by mass, even more preferably 85-100% by mass.

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

(Crosslinking agent)
In one embodiment of the present invention, when the pressure-sensitive adhesive composition (x) contains a pressure-sensitive adhesive resin having a functional group, the pressure-sensitive adhesive composition (x) preferably further contains a crosslinking agent.
The crosslinking agent reacts with the adhesive resin having a functional group, and crosslinks the adhesive resins with the functional group as a crosslinking starting point.

Examples of the crosslinking agent include an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, an aziridine-based crosslinking agent, and a metal chelate-based crosslinking agent.
These crosslinking agents may be used alone or in combination of two or more.
Among these crosslinking agents, an isocyanate-based crosslinking agent is preferable from the viewpoint of increasing the cohesive force to improve the adhesive strength and from the viewpoint of easy availability.

  The content of the crosslinking agent is appropriately adjusted depending on the number of functional groups of the adhesive resin, preferably 0.01 to 10 parts by mass, based on 100 parts by mass of the adhesive resin having a functional group. It is more preferably 0.03 to 7 parts by mass, and still more preferably 0.05 to 5 parts by mass.

(Tackifier)
In one embodiment of the present invention, the pressure-sensitive adhesive composition (x) may further contain a tackifier from the viewpoint of further improving the adhesive strength.
In the present specification, the “tackifier” is a component that assists in improving the adhesive strength of the above-mentioned adhesive resin, and refers to an oligomer having a weight average molecular weight (Mw) of less than 10,000, It is distinguished from the conductive resin.
The weight average molecular weight (Mw) of the tackifier is preferably from 400 to 10,000, more preferably from 500 to 8,000, and still more preferably from 800 to 5,000.

  As the tackifier, for example, a rosin-based resin, a terpene-based resin, a styrene-based resin, a pentene produced by the thermal decomposition of petroleum naphtha, a copolymer of a C5 fraction such as isoprene, piperine, and 1,3-pentadiene are obtained. C5 petroleum resin obtained, a C9 petroleum resin obtained by copolymerizing a C9 fraction such as indene and vinyltoluene generated by thermal decomposition of petroleum naphtha, and a hydrogenated resin obtained by hydrogenating these.

The softening point of the tackifier is preferably from 60 to 170C, more preferably from 65 to 160C, and still more preferably from 70 to 150C.
In the present specification, the “softening point” of the tackifier means a value measured according to JIS K 2531.
The tackifiers may be used alone or in combination of two or more having different softening points and structures.
When two or more tackifiers are used, the weighted average of the softening points of the tackifiers preferably falls within the above range.

  The content of the tackifier is preferably 0.01 to 65% by mass, more preferably 0.1 to 50% by mass, based on the total amount (100% by mass) of the active ingredients of the pressure-sensitive adhesive composition (x). More preferably, it is 1 to 40% by mass, and still more preferably 2 to 30% by mass.

(Adhesive additive)
In one embodiment of the present invention, the pressure-sensitive adhesive composition (x) contains a pressure-sensitive adhesive additive used for a general pressure-sensitive adhesive, in addition to the additives described above, as long as the effects of the present invention are not impaired. It may be.
Examples of such additives for adhesives include antioxidants, softeners (plasticizers), rust inhibitors, pigments, dyes, retarders, reaction accelerators (catalysts), ultraviolet absorbers, antistatic agents, and the like. Is mentioned.
These adhesive additives may be used alone or in combination of two or more.

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

In addition, the pressure-sensitive adhesive layer (X1) may be an expandable pressure-sensitive adhesive layer (X1-1), but from the viewpoint of preventing a decrease in the adhesive force due to leakage of the component contained in the expandable particles, a non-expandable pressure-sensitive adhesive. It is preferably the layer (X1-2). The other pressure-sensitive adhesive layer (X2) is a non-expandable pressure-sensitive adhesive layer. Therefore, the content of the expandable particles in the pressure-sensitive adhesive composition (x), which is a material for forming the pressure-sensitive adhesive layer (X1) and another pressure-sensitive adhesive layer (X2), is preferably as small as possible.
As the content of the expandable particles in the pressure-sensitive adhesive layer (X1) or the other pressure-sensitive adhesive layer (X2), the total amount (100% by mass) of the active ingredient of the pressure-sensitive adhesive composition (x) or the pressure-sensitive adhesive layer ( X1) or other pressure-sensitive adhesive layer (X2), preferably less than 1% by mass, more preferably less than 0.1% by mass, even more preferably less than 0.01% by mass, based on the total mass (100% by mass) of the pressure-sensitive adhesive layer (X2). Even more preferably, it is less than 0.001% by mass.

<Adhesive layer (Z)>
The singulated sheet of one embodiment of the present invention has an adhesive layer (Z). The adhesive layer (Z) is preferably a layer formed from an adhesive composition containing a binder resin (a) and a thermosetting component (b).
The adhesive composition further contains various additives such as an inorganic filler, a curing accelerator, a coupling agent, a crosslinking agent, a plasticizer, an antistatic agent, an antioxidant, a pigment, a dye, and a gettering agent. You may.

  Examples of the binder resin (a) include an acrylic resin, a polyester resin, a urethane resin, an acrylic urethane resin, a silicone resin, a rubber-based polymer, a phenoxy resin, and the like, and an acrylic resin is preferable.

The weight average molecular weight (Mw) of the binder resin (a) is preferably 10,000 to 2,000,000, more preferably 50,000 to 1.8,000,000, and still more preferably 100,000 to 1.5,000,000.
In addition, as the binder resin (a), an acrylic resin having a mass average molecular weight (Mw) of 100,000 or more and a thermoplastic resin having a mass average molecular weight of less than 100,000 (preferably 1,000 to less than 100,000) are used in combination. Is also good.
Examples of the thermoplastic resin include a polyester resin, a urethane resin, a phenoxy resin, polybutene, polybutadiene, and polystyrene.

  The content of the binder resin (a) is preferably 35 to 95% by mass, more preferably 45 to 90% by mass, and still more preferably the total amount (100% by mass) of the active ingredient of the adhesive composition. It is 50 to 80% by mass.

  The thermosetting component (b) preferably contains, for example, a thermosetting resin such as an epoxy resin, a polyimide resin, a polyurethane resin, an unsaturated polyester resin, or a silicone resin, and a thermosetting agent. More preferably, the composition contains a curing agent.

Examples of the epoxy resin include polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and hydrogenated products thereof, orthocresol novolak epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, and bisphenol A type epoxy. Resins, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin and the like.
Examples of the thermosetting agent include compounds having two or more functional groups capable of reacting with an epoxy group in one molecule, and phenol compounds are preferable. Specifically, polyfunctional phenol resins, biphenols, and novolak phenols Resins, dicyclopentadiene-based phenolic resins, aralkylphenolic resins and the like.

The content of the thermosetting agent is preferably from 0.1 to 500 parts by mass, more preferably from 1 to 200 parts by mass, based on 100 parts by mass of the epoxy resin.
Further, the content of the thermosetting component (b) is preferably 5 to 100 parts by mass, more preferably 10 to 75 parts by mass, based on 100 parts by mass of the binder resin (a) in the adhesive composition. Preferably it is 15 to 60 parts by mass.
The “content of the thermosetting component (b)” is the total content of the thermosetting resin and the thermosetting agent.

  The thickness of the adhesive layer (Z) is preferably 1 to 100 μm, more preferably 5 to 75 μm, and still more preferably 5 to 50 μm.

<Release material>
In the individualized sheet of one embodiment of the present invention, a release material may be further laminated on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer (X1), another pressure-sensitive adhesive layer (X2), and the pressure-sensitive adhesive layer (Z).
As the release material, a release sheet that has been subjected to a double-sided release treatment, a release sheet that has been subjected to a single-sided release treatment, or the like is used, and examples thereof include those obtained by applying a release agent on a substrate for a release material.

  Examples of the release material substrate include papers such as high-quality paper, glassine paper, and kraft paper; polyester resin films such as polyethylene terephthalate resin, polybutylene terephthalate resin, and polyethylene naphthalate resin; and olefins such as polypropylene resin and polyethylene resin. And plastic films such as resin films.

  Examples of the release agent include a rubber-based elastomer such as a silicone-based resin, an olefin-based resin, an isoprene-based resin, and a butadiene-based resin, a long-chain alkyl-based resin, an alkyd-based resin, and a fluorine-based resin.

  The thickness of the release 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.

[Method for producing individualized sheet of the present invention]
The method for producing the singulated sheet of the present invention is not particularly limited.
Hereinafter, an example of a method for manufacturing an individualized sheet according to the first to fifth aspects of the present invention will be described.

<Method for producing individualized sheet of first embodiment>
As a method for producing the individualized sheet of the first embodiment, a production method (1) having the following step (1A) is exemplified.
Step (1A): The pressure-sensitive adhesive composition (x) containing expandable particles, which is a material for forming the expandable pressure-sensitive adhesive layer (X1-1), is applied on the surface of the non-expandable base material layer (Y2). Forming a coating film and drying the coating film.

<Method for producing individualized sheet of second embodiment>
As a method for manufacturing the individualized sheet of the second embodiment, a manufacturing method (2) including the following steps (2A) and (2B) is exemplified.
Step (2A): A resin composition (y), which is a material for forming the expandable base material (Y1), is applied on the release-treated surface of the release material to form a coating film, and the coating film is dried or UV-coated. A step of producing an expandable base material (Y1) by irradiation.
Step (2B): A pressure-sensitive adhesive composition (x), which is a material for forming a non-expandable pressure-sensitive adhesive layer (X1-2), is applied on the surface of the produced expandable base material (Y1) to form a coating film. And drying the coating film.

<Method of manufacturing individualized sheet of third embodiment>
As a method for manufacturing the individualized sheet of the third embodiment, a manufacturing method (3) including the following steps (3A) and (3B) is exemplified.
Step (3A): A resin composition (y), which is a material for forming the expandable base material (Y1), is applied on the release-treated surface of the release material to form a coating film, and the coating film is dried or UV-coated. A step of producing an expandable base material (Y1) by irradiation.
Step (3B): The pressure-sensitive adhesive composition (x) containing expandable particles, which is a material for forming the expandable pressure-sensitive adhesive layer (X1-1), is formed on the surface of the prepared expandable base material (Y1). A step of coating to form a coating film and drying the coating film.

<Method for producing individualized sheet of fourth embodiment>
As a method for manufacturing the individualized sheet of the fourth embodiment, a manufacturing method (4) including the following steps (4A) and (4B) is exemplified.
Step (4A): A resin composition (y) that is a material for forming the expandable base material (Y1) is applied on the surface of the non-expandable base material layer (Y2) to form a coating film. A step of drying or UV-irradiating the film to produce a substrate (Y) having an expandable substrate (Y1) and a non-expandable substrate (Y2).
-Step (4B): Non-expanded on the surface of the expandable base material (Y1) of the manufactured base material (Y) having the expandable base material (Y1) and the non-expandable base material (Y2). A step of applying a pressure-sensitive adhesive composition (x), which is a material for forming the pressure-sensitive adhesive layer (X1-2), to form a coating film, and drying the coating film.

<Method for producing individualized sheet of fifth embodiment>
As a method for manufacturing the individualized sheet of the fifth embodiment, a manufacturing method (5) including the following steps (5A) and (5B) is exemplified.
Step (5A): A resin composition (y) as a material for forming the expandable base material (Y1) is applied on the surface of the non-expandable base material layer (Y2) to form a coating film. A step of drying or UV-irradiating the film to produce a substrate (Y) having an expandable substrate (Y1) and a non-expandable substrate (Y2).
-Step (5B): the base material (Y) having the prepared expandable base material (Y1) and the non-expandable base material (Y2) has an expandable property on the surface of the expandable base material (Y1). A step of applying a pressure-sensitive adhesive composition (x) containing expandable particles, which is a material for forming the pressure-sensitive adhesive layer (X1-1), to form a coating film, and drying the coating film.

[Use of the individualized sheet of the present invention]
The individualized sheet of the present invention is used for individualizing an adherend having a division starting point.
The adherend includes, for example, a semiconductor wafer having a circuit surface formed thereon. The semiconductor wafer is, for example, a silicon wafer, a silicon carbide (SiC) wafer, a compound semiconductor wafer (for example, a gallium phosphide (GaP) wafer, a gallium arsenide (GaAs) wafer, an indium phosphide (InP) wafer, a gallium nitride (GaN)). Wafer) and the like. The circuit surface is formed on the surface of the wafer by, for example, an etching method, a lift-off method, or the like.

In order to apply the stealth dicing method to the semiconductor wafer, it is necessary to perform a process of forming a modified region inside the semiconductor wafer. Further, in order to apply the pre-dicing method to the semiconductor wafer, it is necessary to perform a process of forming a groove in the thickness direction from the surface of the semiconductor wafer.
The circuit surface of the semiconductor wafer that has been subjected to these processes in advance may be attached to the adhesive surface of the adhesive layer (X1). Alternatively, these processes may be performed after the circuit surface of the semiconductor wafer on which these processes are not performed is attached to the adhesive surface of the adhesive layer (X1).
The surface of the semiconductor wafer to which the pressure-sensitive adhesive layer (X1) is attached is not limited to the circuit surface, but may be the surface on the opposite side of the circuit surface.

  When a semiconductor chip is manufactured by singulating a semiconductor wafer by a stealth dicing method, a process for forming a modified region inside the semiconductor wafer includes a back surface of the semiconductor wafer (a surface opposite to a circuit surface) or a semiconductor wafer. A method of forming a modified portion by multiphoton absorption by irradiating a laser beam with the surface (circuit surface) as a laser beam incident oblique surface and aligning a converging point inside the work.

On the other hand, the process of forming a groove in the thickness direction from the surface of the semiconductor wafer to be applied to the pre-dicing method may be performed before or after the semiconductor wafer is attached to the pressure-sensitive adhesive layer (X1). Good.
When a semiconductor chip is manufactured by the pre-dicing method, as a process of forming a groove in the thickness direction from the surface of the semiconductor wafer, a method of performing dicing using a known wafer dicing apparatus or the like is used. Here, the groove formed by the pre-dicing method can be a division starting point in the present invention. In this case, an adhesive sheet may be attached to the adherend, the groove formed in the adherend may be used as a division start point, and the division start point may be used to separate the adherend.

  Then, the semiconductor wafer having the modified region as a division starting point is formed with the line-shaped application region or the like by the above-described method in a state where the semiconductor wafer is attached to the singulated sheet of the present invention. Expands, a force is applied to the semiconductor wafer in the shearing direction, a crack is formed starting from the division starting point, and the semiconductor wafer is singulated.

  The adherend is not limited to a semiconductor wafer having a circuit surface formed thereon, and may be a semiconductor wafer having no circuit surface formed. Further, various substrates such as a semiconductor package, an electronic component, a display, a sapphire substrate, and a glass substrate for a panel may be used.

  Note that the individualized sheet of one embodiment of the present invention may be used while holding the surface of the base material (Y) on a hard support such as an iron plate or a glass plate. Accordingly, in a case where the singulated sheet itself of one embodiment of the present invention is formed of a member which is easily deformed by an external force, the singulated sheet itself is suppressed from being deformed by an external force. The force in the shear direction can be reliably applied to the adherend. As a method for holding the surface of the base material (Y) on the hard support, the base (Y) surface of the singulated sheet is brought into contact with a hard support having a plurality of through holes, and the through-hole is provided. And holding the individualized sheet by suction. In addition, there is a method in which another pressure-sensitive adhesive layer (X2) of the individualized sheet of one embodiment of the present invention is attached to a rigid support.

  The present invention will be specifically described with reference to the following examples, but the present invention is not limited to the following examples.

  The physical property values in the following Production Examples and Examples are values measured by the following methods.

<Mass average molecular weight>
Using a gel permeation chromatograph (manufactured by Tosoh Corporation, product name "HLC-8020"), the value was measured under the following conditions, and the value measured in terms of standard polystyrene was used.
(Measurement condition)
-Columns: "TSK guard column HXL-L", "TSK gel G2500HXL", "TSK gel G2000HXL", "TSK gel G1000HXL" (all manufactured by Tosoh Corporation)-Column temperature: 40 ° C
・ Developing solvent: tetrahydrofuran ・ Flow rate: 1.0 mL / min

<Measurement of thickness of each layer>
The thickness was measured using a constant-pressure thickness measuring instrument (model number: “PG-02J”, standard: JIS K6783, Z1702, Z1709) manufactured by TECLOCK Co., Ltd.

<Storage elastic modulus E ′ of thermally expandable base material layer (Y1)>
The formed thermally expandable base material layer (Y1) had a size of 5 mm (length) × 30 mm (width) × 200 μm (thickness), and a sample from which the release material was removed was used as a test sample.
Using a dynamic viscoelasticity measuring device (manufactured by TA Instruments Co., Ltd., product name “DMAQ800”), the test start temperature is 0 ° C., the test end temperature is 300 ° C., the heating rate is 3 ° C./min, the frequency is 1 Hz, and the amplitude is 20 μm. The storage elastic modulus E ′ of the test sample at a predetermined temperature was measured under the following conditions.

<Storage shear modulus G ′ of pressure-sensitive adhesive layer (X1)>
The formed pressure-sensitive adhesive layer (X1) was cut into a circle having a diameter of 8 mm, the peeling material was removed, and the resulting layer was superposed to have a thickness of 3 mm, which was used as a test sample.
Using a viscoelasticity measuring device (manufactured by Anton Paar, device name "MCR300"), a torsional shear method under the conditions of a test start temperature of 0 ° C, a test end temperature of 300 ° C, a heating rate of 3 ° C / min, and a frequency of 1 Hz. The storage shear modulus G ′ of the test sample at a predetermined temperature was measured.

<Probe tack value>
A test sample was obtained by cutting a substrate layer to be measured into a square having a side of 10 mm and leaving it to stand at 23 ° C. and 50% RH (relative humidity) for 24 hours.
In an environment of 23 ° C. and 50% RH (relative humidity), a probe tack value on the surface of the test sample was measured using a tacking tester (product name “NTS-4800”, manufactured by Nippon Tokuso Soki Co., Ltd.) according to JIS. It was measured according to Z0237: 1991.
Specifically, after a stainless steel probe having a diameter of 5 mm was brought into contact with the surface of the test sample for 1 second at a contact load of 0.98 N / cm ² , the probe was moved at a speed of 10 mm / sec. The force required to separate from the surface was measured and the value obtained was taken as the probe tack value of the test sample.

Production Example 1 (Synthesis of acrylic urethane resin)
(1) Synthesis of urethane prepolymer In a reaction vessel under a nitrogen atmosphere, isophorone diisocyanate was added to 100 parts by mass (solid content ratio) of a polycarbonate diol having a weight average molecular weight of 1,000, and hydroxyl groups of the polycarbonate diol and isophorone diisocyanate were added. It is blended so that the equivalent ratio with the isocyanate group becomes 1/1, further, 160 parts by mass of toluene is added, and the mixture is stirred at 80 ° C. until the isocyanate group concentration reaches the theoretical amount while stirring under a nitrogen atmosphere. The reaction was allowed to proceed for more than an hour.
Next, a solution prepared by diluting 1.44 parts by mass (solid content ratio) of 2-hydroxyethyl methacrylate (2-HEMA) in 30 parts by mass of toluene was added, and the mixture was further heated at 80 ° C. until the isocyanate groups at both ends disappeared. The reaction was carried out for 6 hours to obtain a urethane prepolymer having a mass average molecular weight of 29,000.

(2) Synthesis of acrylic urethane-based 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 of methyl methacrylate (MMA) (solid content ratio), To the mixture were added 5.1 parts by mass of 2-hydroxyethyl methacrylate (2-HEMA) (solid content ratio), 1.1 parts by mass of 1-thioglycerol (solid content ratio), and 50 parts by mass of toluene. Temperature.
A solution obtained by further diluting 2.2 parts by mass (solid content ratio) of a radical initiator (manufactured by Nippon Finechem Co., Ltd., product name “ABN-E”) with 210 parts by mass of toluene at 105 ° C. in the reaction vessel. It dripped over 4 hours, maintaining.
After completion of the dropwise addition, the mixture was reacted at 105 ° C. for 6 hours to obtain a solution of an acrylic urethane resin having a weight average molecular weight of 105,000.

Production Example 2 (Production of individualized sheet)
The details of the adhesive resin, additives, heat-expandable particles, base material, and release material used in the formation of each layer when producing the following individualized sheets are as follows.
<Adhesive resin>
Acrylic copolymer (i): having a structural unit derived from a raw material monomer composed of 2-ethylhexyl acrylate (2EHA) / 2-hydroxyethyl acrylate (HEA) = 80.0 / 20.0 (mass ratio). An acrylic copolymer having a Mw of 600,000.
<Additives>
-Isocyanate crosslinking agent (i): manufactured by Tosoh Corporation, product name "Coronate L", solid content concentration: 75% by mass.
<Thermal expandable particles>
Thermal expansion particles (i): Kureha Corporation, product name “S2640”, expansion start temperature (t) = 208 ° C., average particle diameter (D ₅₀ ) = 24 μm, 90% particle diameter (D ₉₀ ) = 49 μm .
<Release material>
-Heavy release film: manufactured by Lintec Corporation, product name "SP-PET382150", a polyethylene terephthalate (PET) film provided with a release agent layer formed of a silicone release agent on one surface, thickness: 38 m.
-Light release film: manufactured by Lintec Co., Ltd., product name "SP-PET381031", a PET film provided with a release agent layer formed of a silicone release agent on one surface, thickness: 38 m.

(1) Formation of Pressure-Sensitive Adhesive Layer (X1) 5.0 parts by weight of the isocyanate-based cross-linking agent (i) was added to 100 parts by weight of the solid content of the acrylic copolymer (i), which is a pressure-sensitive adhesive resin. Ratio), diluted with toluene, and uniformly stirred to prepare a pressure-sensitive adhesive composition having a solid content concentration (active ingredient concentration) of 25% by mass.
Then, the pressure-sensitive adhesive composition is applied to the surface of the release agent layer of the heavy release film to form a coating film, and the coating film is dried at 100 ° C. for 60 seconds to obtain a 5 μm-thick non-expandable adhesive. The pressure-sensitive adhesive layer (X1), which is an agent layer, was formed.
The storage shear modulus G ′ (23) of the pressure-sensitive adhesive layer (X1) at 23 ° C. was 2.5 × 10 ⁵ Pa.

(2) Preparation of base material (Y) To 100 parts by mass of the solid content of the acrylic urethane-based resin obtained in Production Example 1, 6.3 parts by mass of the isocyanate-based crosslinking agent (i) (solid content ratio), 1.4 parts by mass of dioctyltin bis (2-ethylhexanoate) (solid content ratio) and the thermally expandable particles (i) were blended, diluted with toluene, and uniformly stirred to obtain a solid content concentration ( A resin composition having an active ingredient concentration of 30% by mass was prepared.
In addition, the content of the thermally expandable particles (i) was 20% by mass relative to the total amount (100% by mass) of the active ingredients in the obtained resin composition.
Then, the resin composition is applied on the surface of a 50 μm-thick polyethylene terephthalate (PET) film (manufactured by Toyobo Co., Ltd., product name “Cosmoshine A4100”, probe tack value: 0 mN / 5 mmφ) to form a coating film. The coating film was formed, and the coating film was dried at 100 ° C. for 120 seconds to form an intumescent base material layer (Y1) having a thickness of 50 μm.
Here, the PET film corresponds to the non-expandable base material layer (Y2). Therefore, the prepared base material (Y) has a configuration in which the expandable base material layer (Y1) is directly laminated on the non-expandable base material layer (Y2).

In addition, as a sample for measuring the physical property value of the expandable base material layer (Y1), the resin composition is applied to the surface of the release agent layer of the light release film to form a coating film, and It dried at 120 degreeC for 120 second, and formed the 50-micrometer-thick expandable base material layer (Y1) similarly.
Then, based on the above-described measurement method, the storage elastic modulus and the probe tack value at each temperature of the expandable base material layer (Y1) were measured. The measurement results were as follows.
-Storage elastic modulus E '(23) at 23 ° C = 2.0 x 10 ⁸ Pa
-Storage elastic modulus at 208 ° C E '(208) = 5.0 x 10 ⁵ Pa
・ Probe tack value = 0mN / 5mmφ

(3) Lamination of each layer The thermally expandable base material layer (Y1) of the base material (Y) prepared in the above (2) and the pressure-sensitive adhesive layer (X1) formed in the above (1) were laminated.
Then, an individualized sheet was prepared by laminating a heavy release film / adhesive layer (X1) / expandable base material layer (Y1) / non-expandable base material layer (Y2) in this order.

Example <Step (1)>
The singulated sheet prepared in Production Example 2 was cut into a square of 230 mm × 230 mm.
Then, the heavy release film was peeled off, and the exposed adhesive surface of the adhesive layer (X1) was attached to the adherend. As shown in FIG. 6, the adherend WF was a silicon wafer (8 inches) in which a first modified portion MTY and a second modified portion MTX serving as division starting points were formed in advance by laser light.

<Step (2)>
The first energy was applied to the singulated sheet at a temperature of 220 ° C. which was equal to or higher than the expansion start temperature (208 ° C.) of the thermally expandable particles (i). The first energy was applied by a method similar to the method shown in FIG. Specifically, as shown in FIG. 6A, a line-shaped application region LG in which the energy application region extends in the Y-axis direction is formed by the energy irradiation unit 31 at the position where the energy is applied. 1 energy. The energy irradiation means 31 was a hot air irradiation device.
Then, as shown in FIG. 6A, hot air was irradiated from the non-expandable base material layer (Y2) side, and the hot air was sequentially irradiated from ASX1 to ASX2.
As a result, in the energy imparting sheet portion irradiated with the hot air, the thermally expandable particles SG expand to form an infinite number of convex portions CV, and the silicon wafer WF is partially lifted in the hot air irradiation direction, and the silicon wafer WF is partially lifted. A force in the shearing direction was applied to the WF, and the first modified portion MTY was cut off to generate a crack CKY. The silicon wafer WF was singulated into a plurality of strip-shaped WFSs extending in the Y-axis direction.

<Step (3)>
The second energy was applied to the singulated sheet at a temperature of 240 ° C., which was equal to or higher than the expansion start temperature (208 ° C.) of the thermally expandable particles (i). The second energy was applied by a method similar to the method shown in FIG. Specifically, as shown in FIG. 6B, a line-shaped application region LG in which the energy application region extends in the X-axis direction is formed by the energy irradiation unit 31 at the position where the energy is applied. 2 was irradiated.
Then, as shown in FIG. 6B, hot air is irradiated from the non-expandable base material layer (Y2) side, and the hot air is sequentially irradiated from ASY1 to ASY2. In the sheet portion, the thermally expandable particles SG expand further than at the time of the energy irradiation in the step (2), the countless convex portions CV expand, and the strip-shaped silicon wafers WF are partially lifted in the hot air irradiation direction sequentially. Then, a force in the shear direction is applied to the silicon wafer WF, and the second modified portion MTX is triggered to generate a crack CKX. The crack KYX formed earlier and the crack CKX separate the silicon wafer WF. The chip CP was obtained by singulation.

1, 1a, 1b, 1c, 1d, 1e Individualized sheet WF Adherend SG Expandable particles

Claims (9)

Affixed to the adherend, a singulated sheet that singulates the adherend by dividing the starting point formed on the adherend,
It has a substrate (Y) and an adhesive layer (X1),
An individualized sheet including expandable particles that expand when at least one of the base material (Y) and the pressure-sensitive adhesive layer (X1) is applied with a predetermined energy.   The singulated sheet according to claim 1, wherein the base material (Y) has an expandable base material layer (Y1) containing the expandable particles.   The individualized sheet according to claim 2, wherein the base material (Y) further has a non-expandable base material layer (Y2), and the expandable base material layer (Y1) is arranged on the pressure-sensitive adhesive layer (X1) side. .   The individualized sheet according to claim 2 or 3, wherein the pressure-sensitive adhesive layer (X1) is a non-expandable pressure-sensitive adhesive layer (X1-2).   The method according to any of claims 1 to 4, wherein the expandable particles include first expandable particles that expand at a predetermined first energy, and second expandable particles that expand at a predetermined second energy different from the first energy. Or an individualized sheet according to item 1.   The individualized sheet according to any one of claims 1 to 5, wherein the expandable particles are dispersed.   The individualized sheet according to any one of claims 1 to 5, wherein the expandable particles are arranged at a position corresponding to the division starting point of the adherend.   The piece according to any one of claims 1 to 7, wherein an adhesive layer (Z) is laminated on a surface of the pressure-sensitive adhesive layer (X1) opposite to a surface on which the substrate (Y) is laminated. Sheet.   The singulation according to any one of claims 1 to 8, wherein the pressure-sensitive adhesive layer (X2) is laminated on a surface of the substrate (Y) opposite to the surface on which the pressure-sensitive adhesive layer (X1) is laminated. Sheet.