TWI764885B - Complex sheet for forming protective film - Google Patents

Abstract

A complex sheet for forming protective film including a support sheet, a protective film-forming film provided on a surface of the support sheet on one side, and a coating layer provided on a surface of the support sheet opposite to the side where the protective film-forming film is provided, wherein a gloss value of a surface of the coating film opposite to the side on which the protective film-forming film is provided is 32 to 95.

Description

Composite sheet for protective film formation

The present invention relates to a composite sheet for forming a protective film for forming a protective film on the back surface of a semiconductor wafer.

This application claims priority based on Japanese Patent Application No. 2016-042690 for which it applied in Japan on March 4, 2016, and the content of the application is incorporated herein by reference.

In recent years, the industry has used a mounting method called a so-called face down method to manufacture semiconductor devices. In the flip-chip method, a semiconductor wafer having electrodes such as bumps on a circuit surface is used, and the electrodes are bonded to a substrate. Therefore, the back surface of the wafer on the opposite side to the circuit surface may be exposed.

In some cases, a resin film composed of an organic material is formed on the backside of the bare wafer as a protective film, and is incorporated into a semiconductor device in the form of a semiconductor wafer with a protective film. The protective film is used to prevent chip cracking after the dicing step or packaging.

When forming such a protective film, the composite sheet for protective film formation provided with the film for protective film formation on a support sheet is used. As the above-mentioned support sheet, for example, a resin base material or a laminated structure of a base material and an adhesive layer is used, and the laminated layer such as a film for forming a protective film or an adhesive layer of the above-mentioned base material may also be surface-treated. In the aforementioned composite sheet for forming a protective film, the film for forming a protective film has a function of forming a protective film, and the support sheet can function as a dicing sheet, so it can be said that the film for forming a protective film and the dicing sheet are integrally formed. A composite sheet for forming a protective film.

Usually, the single side or both sides of the aforementioned base material before processing for a support sheet have a concavo-convex shape. The reason is that if the base material does not have such a concave-convex shape, when the base material is wound into a roll, the contact surfaces of the base materials adhere to each other to cause blocking, which makes it difficult to use. When at least one of the contact surfaces of the substrates has a concavo-convex shape, the area of the contact surface becomes small, and thus blocking is suppressed.

Typically, the conventional composite sheet for protective film formation using such a base material having an uneven surface has a structure as shown in FIG. 4 . FIG. 4 is a cross-sectional view schematically showing an example of a conventional composite sheet for forming a protective film. In addition, in the drawings used in the following description, for example, in order to facilitate the understanding of the characteristics of the composite sheet for forming a protective film, the part that is the main part is sometimes shown enlarged for convenience, and is not limited to the size of each component. The ratios etc. are the same as the actual ones.

The conventional composite sheet 9 for forming a protective film shown here is provided with a film 13 for forming a protective film on a support sheet 90. The support sheet 90 is composed of a laminated structure of a base material 91 and an adhesive layer 12. The film 13 for protective film formation is provided thereon. The film 13 for protective film formation becomes a protective film by hardening. The composite sheet 9 for protective film formation is further provided with the peeling film 15 on the film 13 for protective film formation, and when using the composite sheet 9 for protective film formation, the peeling film 15 is removed. In the composite sheet 9 for forming a protective film, the surface (back surface) 90b on the opposite side to the surface (surface) 90a provided with the film 13 for forming a protective film in the support sheet 90 is a concavo-convex surface, that is, the surface (back surface) 90b in the base material 91 and the The surface (front surface) 91a of the adhesive layer 12 is the surface (back surface) 91b on the opposite side, which becomes a concavo-convex surface. In the composite sheet 9 for forming a protective film, by forming the back surface 91b of the base material 91 as a concave and convex surface in this way, when the back surface 91b of the base material 91 is wound into a roll, the adhesion of the back surface 91b of the base material 91 and the exposed surface (surface) 15a of the release film 15 is ie Adhesion is inhibited.

On the other hand, in the composite sheet for forming a protective film, the surface on the support sheet side of the protective film formed of the film for forming a protective film may be printed by irradiating laser light (hereinafter, sometimes referred to as "laser printing"). ). At the time of laser printing, irradiation is performed from the side opposite to the side where the protective film of the support sheet is formed. At this time, for example, in the case of the composite sheet 9 for forming a protective film, the protective film is irradiated with laser light through the support sheet 90 from the back surface 91b side of the base material 91. However, since the back surface 91b of the base material 91 is an uneven surface, the The light on the concave and convex surface will be diffusely reflected, and there is a problem that the laser printing is not clear.

As a composite sheet for forming a protective film that can prevent such diffuse reflection of light, a composite sheet 8 for forming a protective film having a structure as shown in FIG. 5 is known (see, for example, Patent Document 1).

FIG. 5 is a cross-sectional view schematically showing another example of a conventional composite sheet for forming a protective film.

The conventional composite sheet 8 for forming a protective film shown here is provided with the film 13 for forming a protective film on a support sheet 80, which is composed of a base material 81 and an adhesive layer, similarly to the composite sheet 9 for forming a protective film. The layered structure structure of 12 includes a film 13 for forming a protective film on the adhesive layer 12 . However, in the support sheet 80 , the arrangement of the uneven surface of the base material 81 is opposite to that of the base material 91 in the support sheet 90 . That is, in the composite sheet 8 for forming a protective film, the surface (surface) 81a of the base material 81 provided with the adhesive layer 12 becomes the uneven surface, and the surface (back surface) 81b of the base material 81 on the opposite side to the surface 81a becomes smooth surface. The base material 81 , the protective film-forming film 13 , and the release film 15 in the support sheet 80 are the same as the base material 91 , the protective film-forming film 13 , and the release film 15 in the support sheet 90 , respectively.

However, in the case of the composite sheet 8 for forming a protective film, the back surface 81b of the base material 81 is a smooth surface, that is, the surface (back surface) on the opposite side to the surface (surface) 80a provided with the adhesive layer 12 in the support sheet 80 ) 80b becomes a smooth surface, and when the composite sheet 8 for forming a protective film is wound into a roll, the back surface 81b of the base material 81 and the exposed surface (surface) 15a of the release film 15 cannot be prevented from adhering, ie, blocking. When blocking occurs, wrinkles will occur in the composite sheet 8 for forming a protective film. When the composite sheet 8 for forming a protective film is wrinkled and unrolled from a roll, the release film 15 is peeled off from the film 13 for forming a protective film. Furthermore, on the surface 81a of the base material 81, the adhesive layer 12 must have a sufficient thickness in order to eliminate the uneven shape. If the thickness of the adhesive layer 12 is insufficient, there is a problem in that the surface (back surface) 13b of the protective film-forming film 13 on the support sheet 80 side has a concavo-convex shape reflecting the concavo-convex shape of the base material 81 . The laser print applied to the surface on the support sheet side of the protective film formed of the film 13 for forming is not clear.

[Prior Art Literature]

[Patent Literature]

Patent Document 1: Japanese Patent No. 5432853.

In this way, the actual situation is that there has not been a composite sheet for forming a protective film that can achieve both blocking suppression and clear laser printing on the protective film.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a composite sheet for forming a protective film for forming a protective film on the back surface of a semiconductor wafer, which can suppress blocking and clear the protective film. laser printing.

One aspect of the present invention is as follows.

(1) In one embodiment of the present invention, there is provided a composite sheet for forming a protective film comprising a film for forming a protective film on one surface of a support sheet, and the film for forming a protective film is provided on one surface of the supporting sheet with the film for forming a protective film. The surface on the opposite side is provided with a coating layer, and the gloss value of the surface on the opposite side from the side in contact with the support sheet in the coating layer is 32 to 95.

(2) In the composite sheet for forming a protective film according to (1), in which the composite sheet for forming a protective film further comprising a release film on the film for forming a protective film is used, the amount of the release film measured by the following method The peel force may be 10 mN/50 mm or less.

(Measuring method of peeling force of peeling film)

A plurality of composite sheets for forming a protective film having a release film on the film for forming a protective film and having a width of 50 mm and a length of 100 mm are stacked so that the coating layers are all oriented in the same direction and the total thickness of the coating layers is 10 μm to 60 μm. , thereby making a laminate in which the first outermost layer is a coating layer and the second outermost layer is a release film. After standing at ℃ for 3 days, the peeling film closest to the coating of the first outermost layer in the lamination direction was peeled off from the adjacent coating under the conditions of peeling speed of 300 mm/min and peeling angle of 180°, and measured this. peeling force.

(3) In the above-mentioned composite sheet for forming a protective film of (1) or (2), the above-mentioned support sheet may be formed by laminating a base material and an adhesive, and the above-mentioned protective film may be The composite sheet for formation is formed by laminating the coating layer, the base material, the adhesive layer, and the film for forming a protective film in this order.

(4) In the composite sheet for protective film formation of the said (3), the said adhesive layer may be an energy ray curable or a non-energy ray curable layer.

(5) In the composite sheet for forming a protective film according to any one of (1) to (4), the film for forming a protective film may be a thermosetting film or an energy ray curable film.

According to the present invention, there is provided a composite sheet for forming a protective film for forming a protective film on the back surface of a semiconductor wafer, which can suppress blocking and can clearly laser-print the protective film.

1, 2, 8, 9‧‧‧Composite sheet for forming protective film

10, 80, 90‧‧‧Support Sheet

10a, 80a, 90a‧‧‧Surface of support sheet

10b, 80b, 90b‧‧‧Back side of support sheet

11, 81, 91‧‧‧Substrate

11a, 81a, 91a‧‧‧Substrate surface

11b, 81b, 91b‧‧‧ backside of substrate

12‧‧‧Adhesive layer

12a‧‧‧The surface of the adhesive layer

13, 23‧‧‧Protective film forming film

13a, 23a‧‧‧The surface of the film for forming a protective film

13b‧‧‧Back surface of protective film forming film

14‧‧‧Coating

14a‧‧‧Coated surface

14b‧‧‧Coated backside

15‧‧‧Peeling film

15a‧‧‧Surface of release film

16‧‧‧Adhesive layer for jig

16a‧‧‧The surface of the adhesive layer for the jig

121‧‧‧The curved peripheral edge of the adhesive layer

122‧‧‧Flat peripheral part of the adhesive layer

d ₁ , d ₂ ‧‧‧diameter

w ₁ , w ₂ ‧‧‧Width

FIG. 1 is a cross-sectional view schematically showing an embodiment of a composite sheet for forming a protective film according to an embodiment of the present invention.

2 is a cross-sectional view schematically showing another embodiment of the composite sheet for forming a protective film according to one embodiment of the present invention.

FIG. 3 is a plan view showing the composite sheet for forming a protective film produced in the Example.

FIG. 4 is a cross-sectional view schematically showing an example of a conventional composite sheet for forming a protective film.

FIG. 5 is a cross-sectional view schematically showing another example of a conventional composite sheet for forming a protective film.

◎Composite sheet for forming protective film

The composite sheet for forming a protective film of the present embodiment is provided with a film for forming a protective film on one surface of a support sheet, and includes a coating on the surface of the supporting sheet on the opposite side to the side on which the film for forming a protective film is provided. layer, and the gloss value of the surface of the coating layer on the opposite side from the side in contact with the support sheet is 32 to 95.

The above-mentioned protective film-forming composite sheet has a gloss value of the surface on the opposite side with the side in contact with the above-mentioned support sheet in the above-mentioned coating. , When the laser light is irradiated from the coating side, the laser light reaches the protective film effectively and stably, so the protective film can be clearly laser printed.

Moreover, when the said composite sheet for protective film formation is provided with the said coating layer which has easy slipperiness and antistatic property, when it winds up into a roll, blocking is suppressed.

Furthermore, in this specification, in the composite sheet for forming a protective film, the film for forming a protective film is cured into a protective film by heating or irradiating energy rays, as long as the laminated structure of the supporting sheet and the protective film can be maintained. , which is called a composite sheet for forming a protective film. In addition, in the composite sheet for forming a protective film, in the case where the support sheet is a laminated structure of a base material and an adhesive layer, the sheet after curing the adhesive layer can also maintain the base material, adhesive The cured product of the adhesive layer, and the film for forming a protective film or the laminated structure of the protective film is called a composite sheet for forming a protective film.

FIG. 1 is a cross-sectional view schematically showing an embodiment of a composite sheet for forming a protective film according to an embodiment of the present invention.

The composite sheet 1 for protective film formation shown here is provided with the film 13 for protective film formation on one surface 10a of the support sheet 10, and the coating layer 14 is provided on the other surface (back surface) 10b of the support sheet 10. Furthermore, the support sheet 10 is formed by laminating a substrate 11 and an adhesive layer 12 , and has an adhesive layer 12 on one surface 11 a of the substrate 11 and a coating layer on the other surface (back) 11 b of the substrate 11 . 14. The film 13 for forming a protective film is provided on the adhesive layer 12 . Further, the composite sheet 1 for forming a protective film further includes a release film 15 on the film 13 for forming a protective film, and the release film 15 is removed when the composite sheet 1 for forming a protective film is used. The film 13 for protective film formation becomes a protective film by hardening.

In the composite sheet 1 for protective film formation, the adhesive layer 12 is laminated on the aforementioned surface 11 a of the base material 11 , and the film 13 for protective film formation is laminated on a part of the surface 12 a of the adhesive layer 12 . In addition, the release film 15 is laminated on the exposed surface of the surface 12a of the adhesive layer 12 where the film for forming a protective film 13 is not laminated, and on the surface 13a (upper surface and side surface) of the film 13 for forming a protective film 13 .

In addition, a void part may exist between the peeling film 15 and the surface 12a of the adhesive layer 12 or the surface 13a of the film 13 for protective film formation. E.g, The above-mentioned void portion is likely to be generated in the side surface of the film 13 for forming a protective film or the region in the vicinity of the film 13 for forming a protective film on the surface 12a of the adhesive layer 12 .

In the composite sheet 1 for forming a protective film, the surface (surface) 14b of the coating layer 14 which is in contact with the support sheet 10 (substrate 11 ) has a gloss value of 32 to 95 on the opposite side (back surface) 14b. Thereby, the protective film can be clearly laser-printed.

In addition, in the present embodiment, the so-called "gloss value of the surface of the coating layer", unless otherwise specified, means the value obtained as follows: according to JIS K 7105, measured from the side opposite to the support sheet side in the coating layer 20° specular gloss of the coated surface.

In addition, the composite sheet 1 for forming a protective film is provided with the coating layer 14, whereby even when the back surface 11b of the base material 11 and the exposed surface (surface) 15a of the release film 15 are adhered, ie, adhered, even when wound into a roll be suppressed.

In the composite sheet 1 for forming a protective film, the surface (back surface) 10b on the opposite side to the surface (surface) 10a provided with the film 13 for forming a protective film in the support sheet 10, that is, the surface (back surface) 10b provided with the adhesive layer in the base material 11. The surface (front surface) 11a of 12 is the surface (back surface) 11b on the opposite side, which is a concavo-convex surface with low smoothness, but may be a smooth surface. When laser-printing is performed on the protective film (not shown) formed of the protective film-forming film 13 , the surface of the protective film on the support sheet 10 side is irradiated with laser light from the coating layer 14 side. At this time, the back surface 10b of the support sheet 10 (the back surface 11b of the base material 11 ) is the difference between the uneven surface and the smooth surface. In either case, the coating layer 14 covers the surface, so that the surface (surface) 14a of the coating layer 14 that is in contact with the support sheet 10 (the base material 11) is the opposite side (back surface) 14b has high smoothness, The surface roughness Ra of the surface (back surface) 14b is small, whereby the diffuse reflection of the laser light on the coating layer 14 can be suppressed, so that the protective film can be clearly laser-printed.

In addition, in this specification, the "surface roughness Ra" means the so-called arithmetic mean roughness defined in JIS B0601:2001 unless otherwise specified.

In the composite sheet 1 for protective film formation, although the surface 11a of the base material 11 becomes a smooth surface here, it may be an uneven surface with low smoothness. However, as will be described later, the base material is preferable in that it is easier to suppress the generation of voids between the surface 11a of the base material 11 and the adhesive layer, and the composite sheet 1 for forming a protective film has preferable properties. The surface 11a of 11 is a smooth surface.

The composite sheet 1 for forming a protective film shown in FIG. 1 is used by attaching the back surface of a semiconductor wafer (not shown) to the surface 13a of the film 13 for forming a protective film with the release film 15 removed. Then, the exposed surface of the surface 12a of the adhesive layer 12 on which the protective film forming film 13 is not laminated is attached to a jig such as a ring frame.

2 is a cross-sectional view schematically showing another embodiment of the composite sheet for forming a protective film according to one embodiment of the present invention. Again, Figure 2 Among them, the same elements as those shown in FIG. 1 are denoted by the same reference numerals as in the case of FIG. 1 , and the detailed description of the reference numerals is omitted. The same applies to the figures after FIG. 2 .

Regarding the composite sheet 2 for forming a protective film shown here, the film 23 for forming a protective film is layered on the entire surface area of the surface 12a of the adhesive layer 12, and a jig is laminated on a part of the surface 23a of the film 23 for forming a protective film. Using the adhesive layer 16, on the surface 23a of the protective film forming film 23, the exposed surface of the adhesive layer 16 for jig is not laminated, and the surface 16a (upper surface and side surface) of the adhesive layer 16 for jig is laminated on the surface 16a (the upper surface and the side surface). The release film 15 is the same as the composite sheet 1 for forming a protective film shown in FIG. 1 except for these points.

In addition, a void part may exist between the peeling film 15 and the surface 23a of the film 23 for protective film formation, or the surface 16a of the adhesive agent layer 16 for jigs. For example, in the side surface of the adhesive layer 16 for a jig and the surface 23a of the film 23 for forming a protective film, the area near the adhesive layer 16 for a jig is likely to generate the aforementioned voids.

In the composite sheet 2 for forming a protective film, as in the case of the composite sheet 1 for forming a protective film, the surface (surface) 14a of the coating layer 14 that is in contact with the support sheet 10 (substrate 11 ) is the surface on the opposite side The gloss value of (back surface) 14b is 32 to 95. Therefore, the protective film formed of the protective film forming film 23 can be clearly laser-printed.

Moreover, since the composite sheet 2 for protective film formation is provided with the coating layer 14, blocking can be suppressed even when it winds up into a roll.

The composite sheet 2 for forming a protective film shown in FIG. 2 is used by attaching the back surface of a semiconductor wafer (not shown) to the surface 23a of the film 23 for forming a protective film with the release film 15 removed. Then, the upper surface of the surface 16a of the adhesive layer 16 for a jig is attached to a jig such as an annular frame.

The composite sheet for forming a protective film of the present invention is not limited to the composite sheet for forming a protective film shown in FIGS. 1 to 2 , and the protective film shown in FIGS. A part of the structure of the composite sheet for film formation is changed or deleted, or another structure is further added to the composite sheet for protective film formation described above.

Hereinafter, each structure of the composite sheet for protective film formation which concerns on one Embodiment of this invention is demonstrated in detail.

○ Support sheet

The above-mentioned support sheet is not particularly limited as long as the above-mentioned protective film-forming film can be provided. For example, it can be enumerated: in order to prevent the peeling sheet of dust etc. from adhering to the surface of the protective film-forming film, and to play a role in the cutting process, etc. A sheet for functions such as a dicing sheet for protecting the surface of a film for forming a protective film.

Preferable examples of the above-mentioned support sheet include those generally used in the field of semiconductor wafer processing sheets consisting of only a base material, and a support sheet formed by laminating a base material and an adhesive.

The support sheet may be constituted by one layer (single layer), or may be constituted by plural layers of two or more layers. When the support sheet is composed of plural layers, these plural layers may be the same or different from each other. That is, all the layers may be the same, all the layers may be different, or only a part of the layers may be the same. In addition, when the plural layers are different from each other, the combination of these plural layers is not particularly limited. Here, that a plurality of layers are different from each other means that at least one of the material and thickness of each layer is different from each other.

The thickness of the support sheet may be appropriately selected according to the purpose, and is preferably 10 μm to 500 μm in terms of imparting sufficient flexibility to the composite sheet for forming a protective film and good adhesion to a semiconductor wafer, and more It is preferably 20 μm to 350 μm, particularly preferably 30 μm to 200 μm.

Here, the so-called "thickness of the support sheet" means the total thickness of each layer constituting the support sheet, for example, in the case of a support sheet formed by laminating a base material and an adhesive, it means the thickness of the base material and the adhesive layer the total thickness of .

Furthermore, at least one surface of the support sheet may be a concave-convex surface, and the thickness of the support sheet may be calculated by taking the tip of the convex portion as a common point in the portion including the convex portion on the concave-convex surface of the support sheet.

‧Substrate

The material of the aforementioned base material is preferably various resins, and specific examples of the resins include polyethylene (low-density polyethylene (LDPE; Low-density Polyethylene), linear low-density polyethylene (LLDPE; Linear). Low-density Polyethylene), high-density polyethylene (HDPE; High-density Polyethylene, etc.), polypropylene, ethylene-propylene copolymer, polybutene, polybutadiene, polymethylpentene, polyvinyl chloride, chlorine Ethylene Copolymer, Polyethylene Terephthalate, Polyethylene Naphthalate, Polybutylene Terephthalate, Polyurethane, Polyurethane Acrylate, Polyimide, Ethylene-vinyl acetate copolymer, ionomer resin, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate copolymer, polystyrene, polycarbonate, fluororesin, any of these resins Hydrogenated products, modified products, cross-linked products or copolymers, etc. In addition, in this specification, the concept of "(meth)acrylic acid" includes both "acrylic acid" and "methacrylic acid".

When the support sheet is formed by laminating the base material and other layers such as an adhesive layer, the thickness of the base material can be appropriately selected according to the purpose, preferably 15 μm to 300 μm, more preferably 20 μm to 200 μm. When the thickness of the base material is in such a range, the flexibility of the composite sheet for forming a protective film and the adhesion to a semiconductor wafer or a semiconductor chip are further improved.

The base material may be constituted by one layer (single layer), or may be constituted by plural layers of two or more layers. When the base material is composed of plural layers, these plural layers may be the same or different from each other. Here, "a plurality of layers may be the same or different from each other" means the same meaning as in the case of the above-mentioned support sheet.

When the base material is composed of a plurality of layers, the total thickness of each layer may be the thickness of the above-mentioned preferred base material.

The surface roughness Ra of the surface (surface) provided with the adhesive layer in the base material is preferably 0.001 μm to 0.1 μm, more preferably 0.005 μm to 0.08 μm, particularly preferably 0.01 μm to 0.04 μm. When the surface roughness Ra of the surface of the base material is equal to or less than the upper limit value, the protective film can be more clearly laser-printed.

The aforementioned surface roughness Ra of the substrate surface can be adjusted, for example, by the molding conditions or surface treatment conditions of the substrate.

Further, as a method of singulating a semiconductor wafer into semiconductor wafers by dicing, for example, a method of using the following dicing methods: blade dicing for cutting into the semiconductor wafer with a blade, and laser cutting for cutting into the semiconductor wafer by laser irradiation are exemplified. jet dicing, or water dicing by blowing water containing abrasives into semiconductor wafers, etc.

On the other hand, as a method of singulating a semiconductor wafer into a semiconductor wafer, in addition to these methods of dicing, a method of irradiating the infrared region so as to focus on a focal point set inside the semiconductor wafer may be exemplified. After the laser light forms a modified layer inside the semiconductor wafer, it exerts force on the semiconductor wafer, thereby dividing and singulating the semiconductor wafer at the portion where the modified layer is formed.

When the surface roughness Ra of the surface of the base material is, for example, 0.01 μm to 0.2 μm, the composite sheet for forming a protective film provided with such a base material is preferably formed by forming a modified layer inside the above-mentioned semiconductor wafer and forming a semiconductor wafer. Used for wafer singulation.

On the other hand, the surface roughness Ra of the surface (back surface) opposite to the surface (surface) provided with the adhesive layer in the substrate, in other words, the surface (surface) provided with the protective film forming film in the support sheet is The surface roughness Ra of the opposite side (back surface) is preferably 0.001 μm to 4 μm, more preferably 0.005 μm to 3.7 μm, further preferably 0.01 μm to 3.4 μm, particularly preferably 0.02 μm to 3.1 μm. When the surface roughness Ra of the back surface of the substrate is below the upper limit value, the surface roughness Ra of the surface on the opposite side from the side in contact with the support sheet in the coating layer can be more easily reduced, thereby making it easier to protect. The film is clearly laser printed.

The aforementioned surface roughness Ra of the back surface of the substrate can be adjusted, for example, by the molding conditions or surface treatment conditions of the substrate.

The resin used as the material of the base material may also be cross-linked.

In addition, the resin as the material of the base material may be formed into a sheet by extrusion of a thermoplastic resin, or may be formed into a sheet by stretching, or may be formed into a sheet by thinning and curing of a curable resin by a known method.

In addition, the substrate may be colored or printed.

It is preferable that the base material contains polypropylene because it is excellent in heat resistance, and has a suitable stretchability and a good pick-up property by having moderate flexibility.

The polypropylene-containing substrate may be, for example, a single-layer or plural-layer substrate composed of polypropylene alone, or a plural-layer substrate in which a polypropylene layer and a resin other than polypropylene are laminated.

When the film for forming a protective film is thermosetting, since the base material has heat resistance, the heat-induced deterioration of the base material can be suppressed, and the occurrence of defects in the manufacturing process of the semiconductor device can be effectively suppressed.

In order to improve the adhesion between the base material and the adhesive layer or protective film-forming film provided on the base material, the surface of the base material may be subjected to roughening treatment by sandblasting, solvent treatment, etc., corona discharge treatment, electronic Beam irradiation treatment, plasma treatment, ozone/ultraviolet irradiation treatment, flame treatment, chromic acid treatment, oxidation treatment such as hot air treatment, etc. In addition, a primer treatment may be performed on the surface of the substrate.

‧Adhesive layer

As the above-mentioned adhesive layer, a known adhesive layer can be suitably used.

The adhesive layer can be formed using an adhesive composition, which constitutes the adhesive layer and contains various components such as an adhesive. The content ratio of components that do not vaporize at room temperature in the adhesive composition is usually the same as the content ratio of the above-mentioned components in the adhesive layer. In addition, in this specification, "normal temperature" means the temperature which is not particularly cold or particularly hot, that is, a normal temperature, for example, a temperature of 15°C to 25°C, and the like.

The thickness of the adhesive layer can be appropriately selected according to the purpose, and is preferably 1 μm to 100 μm, more preferably 2 μm to 80 μm, and particularly preferably 3 μm to 50 μm.

The adhesive layer can be composed of one layer (single layer), or it can also be composed of two or more layers. composed of several layers. When the adhesive layer is composed of plural layers, these plural layers may be the same or different from each other. Here, "a plurality of layers may be the same or different from each other" means the same meaning as in the case of the above-mentioned support sheet.

When the adhesive layer is composed of a plurality of layers, the total thickness of each layer may be the thickness of the above-mentioned preferred adhesive layer.

Examples of the above-mentioned adhesive include adhesive resins such as acrylic resins, urethane resins, rubber-based resins, polysiloxane-based resins, and vinyl ether-based resins. In the case of focusing on the functions of the resins For example, energy ray curable resin etc. are mentioned.

In addition, in this specification, an "energy ray" means an electromagnetic wave or a charged particle beam which has an energy quantum, and an ultraviolet-ray, an electron beam, etc. are mentioned as an example of this energy ray. The ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion H-type lamp, a xenon lamp, or the like as an ultraviolet source. The electron beam may be irradiated with an electron beam generated by an electron beam accelerator or the like.

As said energy ray curable resin, resin which has a polymerizable group, such as a (meth)acryloyl group and a vinyl group, is mentioned, for example.

The aforementioned adhesive resin is preferably an acrylic resin, more preferably a (meth)acrylate copolymer containing a structural unit derived from a (meth)acrylate.

When the above-mentioned adhesive layer contains a component polymerized by irradiation with energy ray, such as an energy ray-curable resin, it becomes energy ray-curable, and the adhesiveness of the adhesive layer is reduced by irradiating the energy ray, and it is easy to The semiconductor wafer with a protective film mentioned later is picked up. Such an adhesive layer can be formed using, for example, various adhesive compositions containing components polymerized by energy ray irradiation.

<<Adhesive composition>>

Preferable examples of the adhesive composition include those containing components polymerized by irradiation with energy rays. Examples of such adhesive compositions include acrylic resins and energy ray polymerizable compounds. The adhesive composition (hereinafter, sometimes referred to as "adhesive composition (i)"); the adhesive composition containing acrylic resin and isocyanate crosslinking agent (hereinafter, sometimes referred to as "adhesive composition (i)"); (ii)"), etc., the aforementioned acrylic resin is an acrylic resin having a hydroxyl group and a polymerizable group in the side chain (for example, an acrylic resin having a hydroxyl group and having a polymerizable group in the side chain via a urethane bond) resin).

<Adhesive composition (i)>

The adhesive composition (i) contains the aforementioned acrylic resin and the energy ray polymerizable compound as essential components.

Hereinafter, each component will be described.

[acrylic resin]

As the aforementioned acrylic resin preferable in the adhesive composition (i), for example, (meth)acrylic acid ester and (meth)acrylic acid which is optionally used can be mentioned. A (meth)acrylate copolymer obtained by polymerizing monomers other than alkenoate as a monomer.

As said (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, (meth)acrylic acid are mentioned, for example Amyl ester, hexyl (meth)acrylate, heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, ( n-nonyl meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate ((meth)acrylate ) lauryl acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, ( Cetyl meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate) , isostearyl (meth)acrylate (isostearyl (meth)acrylate), etc. The alkyl group constituting the alkyl ester is a (meth)acrylate alkyl group with a chain structure with a carbon number of 1 to 18 (Meth) cycloalkyl (meth)acrylates such as isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate; (meth)acrylate aralkyl esters such as benzyl (meth)acrylate; ( (Meth) cycloalkenyl acrylates such as dicyclopentenyl meth)acrylate; (meth) cycloalkenyloxyalkyl acrylates such as dicyclopentenyloxyethyl (meth)acrylate; ) Acrylimide; Glycidyl (meth)acrylate and other glycidyl-containing (meth)acrylates; (meth)acrylate hydroxymethyl, (meth)acrylate 2-hydroxyethyl, (meth)acrylate ) 2-hydroxypropyl acrylate, 3-hydroxypropyl (meth)acrylate, 2-(meth)acrylate Hydroxybutyl, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate and other hydroxyl-containing (meth)acrylates.

As a monomer other than the said (meth)acrylate, (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylol acrylamide etc. are mentioned, for example.

Various monomers, such as the said (meth)acrylate and monomers other than the said (meth)acrylate which comprise an acrylic resin, may be only 1 type, and may be 2 or more types.

The acrylic resin contained in the adhesive composition (i) may be only one type or two or more types.

The content of the acrylic resin in the adhesive composition (i) is preferably 40% by mass to 99% by mass, more preferably 50% by mass relative to the total amount of all components other than the solvent in the adhesive composition (i) mass % to 91 mass %.

[Energy ray polymerizable compound]

The aforementioned energy ray polymerizable compound is a compound that is polymerized and cured by irradiation with energy rays, and examples of the compound include compounds having an energy ray polymerizable group such as an energy ray-curable double bond in the molecule.

Examples of the energy ray polymerizable compound include low-molecular-weight compounds (monofunctional or polyfunctional monomers and oligomers) having an energy ray polymerizable group, and more specifically, trimethylolpropane trimethylolide Acrylates, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate Acrylates such as acrylates; acrylates containing cyclic aliphatic skeletons such as dicyclopentadiene dimethoxydiacrylate; polyethylene glycol diacrylates, oligoester acrylates, acrylic urethane oligomers acrylic compounds, epoxy-modified acrylates, polyether acrylates, itaconic acid oligomers, etc.

The molecular weight of the energy ray polymerizable compound is preferably from 100 to 30,000, more preferably from 300 to 10,000.

The energy ray polymerizable compound contained in the adhesive composition (i) may be only one type or two or more types.

The content of the energy ray polymerizable compound in the adhesive composition (i) is preferably 1 to 125 parts by mass, more preferably 10 to 125 parts by mass relative to 100 parts by mass of the content of the acrylic resin.

[Photopolymerization initiator]

The adhesive composition (i) may contain a photopolymerization initiator in addition to the aforementioned acrylic resin and the energy ray polymerizable compound.

The aforementioned photopolymerization initiator may be a known photopolymerization initiator, and specific examples thereof include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α- Hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-1-{4-[4-(2-hydroxy -2-Methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one and other α-keto alcohol compounds; methoxyacetophenone, 2,2-dimethoxy yl-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholine Acetophenone-based compounds such as propane-1-one; benzoin ether-based compounds such as benzoin ethyl ether, benzoin isopropyl ether, anisin methyl ether, etc.; ketal-based compounds such as benzoin dimethyl ketal; 2-naphthalenesulfonic acid Aromatic sulfonic acid chloride-based compounds such as acyl chloride; photoactive oxime-based compounds such as 1-benzophenone-1,1-propanedione-2-(o-ethoxycarbonyl) oxime; benzophenone, benzylbenzene Formic acid, 3,3'-dimethyl-4-methoxybenzophenone and other benzophenone-based compounds; thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-Dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone Isothioxanthone compounds; camphorquinone; halogenated ketones; acyl phosphine oxide; acyl phosphonates/esters, etc.

The photopolymerization initiator contained in the adhesive composition (i) may be only one type or two or more types.

In the case of using a photopolymerization initiator, the content of the photopolymerization initiator in the adhesive composition (i) is preferably 0.1 to 10 parts by mass relative to 100 parts by mass of the energy ray polymerizable compound content portion, better It is 1 mass part to 5 mass parts. When the said content of a photopolymerization initiator is more than the said lower limit, sufficient effect by using a photopolymerization initiator can be obtained. Moreover, since the said content of a photoinitiator is below the said upper limit, generation|occurrence|production of a by-product from an excess photoinitiator can be suppressed, and hardening of an adhesive bond layer can be performed more favorably.

[Crosslinking agent]

The adhesive composition (i) may contain a crosslinking agent in addition to the aforementioned acrylic resin and the energy ray polymerizable compound.

As said crosslinking agent, an organic polyvalent isocyanate compound, an organic polyvalent imine compound, etc. are mentioned, for example.

Examples of the organic polyvalent isocyanate compound include aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, alicyclic polyvalent isocyanate compounds, and trimers, isocyanurates, and adducts of these compounds; An aromatic polyvalent isocyanate compound, an aliphatic polyvalent isocyanate compound, or an alicyclic polyvalent isocyanate compound and a polyol compound are reacted with a terminal isocyanate urethane prepolymer, and the like. The aforementioned adduct means the aforementioned aromatic polyvalent isocyanate compound, aliphatic polyvalent isocyanate compound or alicyclic polyvalent isocyanate compound, which is mixed with ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil and other low molecular weight compounds. Reactants for active hydrogen compounds.

As said organic polyvalent isocyanate compound, more specifically, 2, 4- toluene diisocyanate; 2, 6- toluene diisocyanate; 1, 3- xylylene diisocyanate; 1, 4- xylene diisocyanate are mentioned, for example Isocyanates; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone Diisocyanate; Dicyclohexylmethane-4,4'-diisocyanate; Dicyclohexylmethane-2,4'-diisocyanate; All or part of the hydroxyl groups of polyols such as p-trimethylolpropane, added with toluene diisocyanate and Compounds of either or both of hexamethylene diisocyanate; lysine diisocyanate, etc.

As said organic polyvalent imine compound, for example, N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), trimethylolpropane-tri-β-nitrogen Propidyl propionate, tetramethylolmethane-tri-beta-aziridinyl propionate, N,N'-toluene-2,4-bis(1-aziridinecarboxamide) tris-ethyl melamine, etc.

When an isocyanate compound is used as a crosslinking agent, it is preferable to use a hydroxyl-containing polymer as an acrylic resin. When the crosslinking agent has an isocyanate group and the acrylic resin has a hydroxyl group, the crosslinked structure can be easily introduced into the adhesive layer by the reaction between these isocyanate groups and the hydroxyl group.

The crosslinking agent contained in the adhesive composition (i) may be only one type or two or more types.

In the case of using a crosslinking agent, the content of the crosslinking agent in the adhesive composition (i) is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the content of the aforementioned acrylic resin, more preferably 0.1 parts by mass to 16 parts by mass.

[solvent]

The adhesive composition (i) preferably further contains a solvent in addition to the aforementioned acrylic resin and the energy ray polymerizable compound.

The aforementioned solvent is not particularly limited, and preferable examples of the aforementioned solvent include hydrocarbons such as toluene and xylene; methanol, ethanol, 2-propanol, isobutanol (2-methylpropan-1-ol), 1 - Alcohols such as butanol; Esters such as ethyl acetate; Ketones such as acetone and methyl ethyl ketone; Ethers such as tetrahydrofuran; )Wait.

The solvent contained in the adhesive composition (i) may be only one type or two or more types.

When the adhesive composition (i) contains a solvent, the content of the solvent is preferably 40 to 90 mass %, more preferably 50 to 80 mass %.

[other ingredients]

In the adhesive composition (i), in addition to the aforementioned acrylic resin and the energy ray polymerizable compound, it may also contain other substances not belonging to the aforementioned photopolymerization initiator, crosslinking agent and solvent within the scope of impairing the effect of the present invention. other ingredients.

The above-mentioned other components may be known components, and can be arbitrarily selected according to the purpose without particular limitation. Examples of preferable other components include: dyes, pigments, anti-deterioration agents, antistatic agents, flame retardants, polysiloxanes Various additives such as compounds and chain transfer agents.

The said other component contained in an adhesive composition (i) may be only 1 type, and may be 2 or more types.

<Adhesive composition (ii)>

The adhesive composition (ii) contains, as essential components, an acrylic resin and an isocyanate-based crosslinking agent, and the aforementioned acrylic resin is an acrylic resin having a hydroxyl group and a polymerizable group in the side chain (for example, having a hydroxyl group and passing through an aminomethyl group) Acrylic resins having a polymerizable group in the side chain with an acid ester bond).

In the case of using the adhesive composition (ii), since the acrylic resin has a polymerizable group in the side chain, compared with the case of the adhesive composition (i), the energy ray polymerizable compound is used by When the polymerization reaction is performed by irradiating the energy ray, the adhesiveness of the adhesive layer after the polymerization reaction (curing) is reduced, the peelability from the adherend is improved, and the pick-up property of the semiconductor wafer with the protective film is improved.

In addition, in this specification, the description of "acrylic resin" in the adhesive composition (ii) means "acrylic resin having a polymerizable group in a side chain" unless otherwise specified.

[acrylic resin]

As the acrylic resin having a polymerizable group in the side chain, for example, an acrylic resin obtained by combining a (meth)acrylate having no hydroxyl group as a monomer and a hydrocarbon group-free (meth)acrylate having a hydroxyl group, and A hydroxyl-containing compound such as a hydroxyl-containing (meth)acrylate is copolymerized to obtain a hydroxyl-containing copolymer, so that the hydroxyl group of the obtained hydroxyl-containing copolymer and the compound having an isocyanate group and a polymerizable group are The isocyanate group reacts to form a urethane bond, thereby obtaining an acrylic resin.

As said hydroxyl group-free (meth)acrylate, for example, among the (meth)acrylates in the adhesive composition (i), (meth)acrylic acid other than the hydroxyl group-containing (meth)acrylate can be mentioned. ester.

Moreover, as said hydroxyl-containing compound, the compound similar to the hydroxyl-containing (meth)acrylate in an adhesive composition (i) is mentioned.

The hydroxyl group-free (meth)acrylate and the hydroxyl group-containing compound constituting the above-mentioned acrylic resin may be only one type, respectively, or two or more types may be used.

As a compound which has the said isocyanate group and a polymerizable group, isocyanate group-containing (meth)acrylates, such as 2-methacryloyloxyethyl isocyanate, are mentioned, for example.

The compound which has the said isocyanate group and a polymerizable group which comprises the said acrylic resin may be only 1 type, and may be 2 or more types.

The acrylic resin contained in the adhesive composition (ii) may be only one type or two or more types.

The content of the acrylic resin in the adhesive composition (ii) is preferably 80% by mass to 99% by mass, more preferably 90% by mass relative to the total amount of all components other than the solvent in the adhesive composition (ii) mass % to 97 mass %.

[Isocyanate based crosslinking agent]

As said isocyanate type crosslinking agent, the same compound as the said organic polyvalent isocyanate compound which is a crosslinking agent in an adhesive composition (i) is mentioned, for example.

Only one type of isocyanate-based crosslinking agent contained in the adhesive composition (ii) may be used, or two or more types may be used.

The molar number of isocyanate groups in the isocyanate-based crosslinking agent in the adhesive composition (ii) is preferably 0.2 relative to the molar number of hydroxyl groups in the acrylic resin in the adhesive composition (ii) times to 3 times. Since the said molar number of an isocyanate group is more than the said lower limit, the adhesiveness of the adhesive layer after hardening falls, the peelability from a to-be-adhered body improves, and the pick-up property of the semiconductor wafer with a protective film improves. Moreover, by the said molar number of an isocyanate group being below the said upper limit, generation|occurrence|production of a by-product by the reaction of isocyanate type crosslinking agents can be suppressed further.

The content of the isocyanate-based crosslinking agent in the adhesive composition (ii) may be appropriately adjusted so that the number of moles of isocyanate groups falls within the above-mentioned range, but it is preferable to satisfy such a condition, and relative to the acrylic acid-based crosslinking agent. The content of the resin is 0.01 to 20 parts by mass per 100 parts by mass, more preferably 0.1 to 15 parts by mass, and particularly preferably 0.3 to 12 parts by mass.

[Photopolymerization initiator]

The adhesive composition (ii) may contain a photopolymerization initiator in addition to the aforementioned acrylic resin and isocyanate-based crosslinking agent.

As said photoinitiator, the photoinitiator similar to the case of an adhesive composition (i) is mentioned, for example.

The photopolymerization initiator contained in the adhesive composition (ii) may be only one type or two or more types.

In the case of using a photopolymerization initiator, the content of the photopolymerization initiator in the adhesive composition (ii) is preferably 0.05 to 20 parts by mass relative to 100 parts by mass of the content of the acrylic resin.

When the said content of a photopolymerization initiator is more than the said lower limit, sufficient effect by using a photopolymerization initiator can be obtained. Moreover, since the said content of a photoinitiator is below the said upper limit, generation|occurrence|production of a by-product from an excess photoinitiator can be suppressed, and hardening of an adhesive bond layer can be performed more favorably.

[solvent]

The adhesive composition (ii) preferably further contains a solvent in addition to the aforementioned acrylic resin and isocyanate-based crosslinking agent.

As said solvent, the thing similar to the case of an adhesive composition (i) is mentioned, for example.

The solvent contained in the adhesive composition (ii) may be only one type or two or more types.

When the adhesive composition (ii) contains a solvent, the content of the solvent is preferably 40 to 90 mass %, more preferably 50 to 80 mass %.

[other ingredients]

In addition to the aforementioned acrylic resin and isocyanate-based crosslinking agent, the adhesive composition (ii) may also contain other components that do not belong to the aforementioned photopolymerization initiator and solvent within the scope of impairing the effect of the present invention.

As said other component, the thing similar to the case of an adhesive composition (i) is mentioned, for example.

The said other component contained in an adhesive composition (ii) may be only 1 type, and may be 2 or more types.

Heretofore, the adhesive composition containing the component polymerized by irradiation with energy ray has been described, but when forming the adhesive layer, an adhesive composition containing no component polymerized by irradiation with energy ray can also be used. That is, the adhesive layer may be a non-energy ray sclerosing layer which does not have energy ray sclerosis.

As such a preferable non-energy ray-curable adhesive composition, for example, an adhesive composition containing an acrylic resin and a crosslinking agent (hereinafter, may be simply referred to as "adhesive composition (iii)"), etc. , and may contain optional components such as solvents and other components that are not solvents.

<Adhesive composition (iii)>

The aforementioned acrylic resin, crosslinking agent, solvent and other components contained in the adhesive composition (iii) are the same as those in the adhesive composition (i).

The content of the acrylic resin in the adhesive composition (iii) is preferably 40% by mass to 99% by mass, more preferably 50% by mass relative to the total amount of all components other than the solvent in the adhesive composition (iii) mass % to 93 mass %.

The content of the crosslinking agent in the adhesive composition (iii) is preferably 3 to 30 parts by mass, more preferably 5 to 25 parts by mass, relative to 100 parts by mass of the content of the acrylic resin.

The adhesive composition (iii) is the same as the adhesive composition (i) except for the above-mentioned aspects.

<<Manufacturing method of adhesive composition>>

The aforementioned adhesive compositions such as the adhesive composition (i) to the adhesive composition (iii) can be obtained by the following methods: Components other than the above-mentioned adhesive are prepared for the components constituting each adhesive composition.

The order of addition at the time of preparing each component is not particularly limited, and two or more components may be added at the same time.

The method of mixing the components during preparation is not particularly limited, and may be appropriately selected from the following well-known methods: a method of mixing by rotating a stirrer or a stirring blade, a method of mixing using a mixer, and a method of applying ultrasonic waves for mixing method etc.

The temperature and time at the time of adding and mixing each component are not particularly limited as long as each compounded component is not degraded, and may be appropriately adjusted, and the temperature is preferably 15°C to 30°C.

○ Film for protective film formation

The film for forming a protective film may be any of thermosetting properties and energy ray curing properties. The film for protective film formation finally becomes a protective film with high impact resistance by hardening. The protective film prevents, for example, cracks from occurring in the semiconductor wafer after the dicing step.

The film for forming a protective film can be formed using a composition for forming a thermosetting protective film or a composition for forming an energy ray curable protective film (hereinafter, these may be collectively referred to as a "composition for forming a protective film") to be described later.

The film for forming a protective film may be only one layer (single layer), or it may be a plurality of layers of two or more layers. In the case of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is not particularly limited.

The thickness of the film for forming a protective film is not particularly limited, but is preferably 1 μm to 100 μm, more preferably 5 μm to 75 μm, and particularly preferably 5 μm to 50 μm. When the thickness of the film for protective film formation is more than the said lower limit, the adhesive force with respect to the semiconductor wafer and the semiconductor chip which are to-be-adhered bodies becomes large. Moreover, when the thickness of the film for protective film formation is below the said upper limit, when picking up a semiconductor wafer, the protective film which is a cured product can be cut|disconnected more easily by shearing force.

‧Film for forming thermosetting protective film

As a preferable film for thermosetting protective film formation, the film containing a polymer component (A) and a thermosetting component (B) is mentioned, for example. The polymer component (A) is regarded as a component formed by a polymerization reaction of a polymerizable compound. Moreover, a thermosetting component (B) is a component which can perform a hardening (polymerization) reaction using heat as a trigger of a reaction. In addition, in this embodiment, a polycondensation reaction is also included in a polymerization reaction.

<<The composition for forming a thermosetting protective film>>

The film for thermosetting protective film formation can be formed using the composition for thermosetting protective film formation containing the constituent material of the film for thermosetting protective film formation. For example, the film for thermosetting protective film formation can be formed in a target site|part by apply|coating the composition for thermosetting protective film formation to the formation object surface of the film for thermosetting protective film formation, and drying as needed. Components that do not vaporize at room temperature in the composition for forming a thermosetting protective film The content ratio of is usually the same as the content ratio of the aforementioned components in the film for forming a thermosetting protective film. Here, the so-called "normal temperature" is as described above.

What is necessary is just to apply|coat the composition for thermosetting protective film formation by a well-known method, for example, the method using the following various coaters is mentioned: Air knife coater, knife coater, bar coater, gravure coater machine, roll coater, roll knife coater, curtain coater, die coater, knife coater, screen coater, meyer bar coater, contact coating machine, etc.

The drying conditions of the composition for forming a thermosetting protective film are not particularly limited, and when the composition for forming a thermosetting protective film contains a solvent to be described later, it is preferable to perform heat drying; Dry at 70°C to 130°C for 10 seconds to 5 minutes.

<The composition for forming a protective film (III-1)>

Examples of the composition for forming a thermosetting protective film include a composition (III-1) for forming a thermosetting protective film containing a polymer component (A) and a thermosetting component (B) (in this specification, there are It is abbreviated as "the composition for forming a protective film (III-1)") and the like.

[Polymer component (A)]

The polymer component (A) is a polymer compound for imparting film-forming properties, flexibility, and the like to the film for forming a thermosetting protective film.

The polymer component (A) contained in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may be only one type or two or more types; in the case of two or more types , the combination and ratio of these can be arbitrarily selected.

As the polymer component (A), for example, acrylic resins (resins having a (meth)acryloyl group), polyesters, urethane resins (resins having urethane bonds), Acrylic urethane resin, polysiloxane-based resin (resin with siloxane bond), rubber-based resin (resin with rubber structure), phenoxy resin, thermosetting polyimide, etc., preferably It is acrylic resin.

As said acrylic resin in a polymer component (A), a well-known acrylic polymer is mentioned.

The weight average molecular weight (Mw) of the acrylic resin is preferably from 10,000 to 2,000,000, more preferably from 100,000 to 1,500,000. The shape stability (time-dependent stability at the time of storage) of the film for thermosetting protective film formation improves by the weight average molecular weight of an acrylic resin being more than the said lower limit. In addition, when the weight-average molecular weight of the acrylic resin is equal to or less than the above-mentioned upper limit, the film for forming a thermosetting protective film can easily follow the uneven surface of the adherend, and the adherence and the thermosetting protective film can be further restrained. A void or the like is generated between the films for formation.

The glass transition temperature (Tg) of the acrylic resin is preferably -60°C to 70°C, more preferably -30°C to 50°C. By the Tg of acrylic resin as the former More than the said lower limit, the adhesive force of a protective film and a support sheet can be suppressed, and the peelability of a support sheet improves. Moreover, since the Tg of an acrylic resin is below the said upper limit, the adhesive force of the film for thermosetting protective film formation, a protective film, and a to-be-adhered body improves.

Examples of acrylic resins include polymers of one or more (meth)acrylates; polymers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N- Copolymers of two or more monomers, such as methylol acrylamide, etc.

As said (meth)acrylate which comprises an acrylic resin, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate are mentioned, for example ester, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-butyl (meth)acrylate, 3-butyl (meth)acrylate, amyl (meth)acrylate, (meth)acrylate (methyl)hexyl acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-octyl (meth)acrylate Nonyl ester, isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate) , tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, ten (meth)acrylate Hexaalkyl esters (palmityl (meth)acrylate), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate), etc. constitute alkyl esters The alkyl group is one of the chain structure with carbon number from 1 to 18. Alkyl (meth)acrylate; (meth)cycloalkyl (meth)acrylate such as isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate; (meth)acrylate such as benzyl (meth)acrylate Aralkyl acrylates; (meth) cycloalkenyl acrylates such as dicyclopentenyl acrylate; (meth) cycloalkenyl acrylates such as dicyclopentenyloxyethyl (meth)acrylate Alkyl ester; (meth)acrylimide; (meth)acrylate and other glycidyl group-containing (meth)acrylates; (meth)acrylate hydroxymethyl, (meth)acrylate 2- Hydroxyethyl, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, (meth)acrylate (meth)acrylates containing hydroxyl groups such as 4-hydroxybutyl acrylate; (meth)acrylates containing substituted amino groups such as N-methylaminoethyl (meth)acrylates. Here, the "substituted amino group" means a group in which one or two hydrogen atoms of the amino group are substituted with a group other than a hydrogen atom.

For example, the acrylic resin may be selected from the group consisting of (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylol acrylamide, and the like in addition to the aforementioned (meth)acrylate. A resin obtained by copolymerizing one or two or more monomers.

Only one kind of monomers constituting the acrylic resin may be used, or two or more kinds thereof may be sufficient; in the case of two or more kinds, the combination and ratio of these may be arbitrarily selected.

The acrylic resin may also have functional groups that can bond with other compounds, such as vinyl groups, (meth)acryloyl groups, amine groups, hydroxyl groups, carboxyl groups, and isocyanate groups. The functional group in the acrylic resin may be bonded to other compounds via the crosslinking agent (F) described later, or may be directly bonded to other compounds without the crosslinking agent (F). There exists a tendency for the reliability of the package obtained using the composite sheet for protective film formation to improve by making an acrylic resin couple|bond with another compound via the said functional group.

In the present embodiment, as the polymer component (A), a thermoplastic resin other than the acrylic resin (hereinafter, only abbreviated as "thermoplastic resin" in some cases) may be used together with the acrylic resin.

By using the above-mentioned thermoplastic resin, the peelability of the protective film from the support sheet may be improved, or the film for forming a thermosetting protective film may easily follow the uneven surface of the adherend, thereby further suppressing the adherence and thermosetting. Pores, etc. are generated between the films for forming a protective film.

The weight average molecular weight of the aforementioned thermoplastic resin is preferably 1,000 to 100,000, more preferably 3,000 to 80,000.

The glass transition temperature (Tg) of the aforementioned thermoplastic resin is preferably -30°C to 150°C, more preferably -20°C to 120°C.

As said thermoplastic resin, a polyester, a polyurethane, a phenoxy resin, a polybutene, a polybutadiene, a polystyrene etc. are mentioned, for example.

The above-mentioned thermoplastic resin contained in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds; Combinations and ratios can be arbitrarily selected.

In the composition for forming a protective film (III-1), irrespective of the type of the polymer component (A), the content of the polymer component (A) (that is, the polymer component in the film for forming a thermosetting protective film ( The ratio of the content of A) to the total content of all components other than the solvent is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, and still more preferably 15 to 35% by mass .

The polymer component (A) may also correspond to the thermosetting component (B). In the present embodiment, in the case where the composition (III-1) for forming a protective film contains such a component conforming to both the polymer component (A) and the thermosetting component (B), the composition for forming a protective film (III-1) (III-1) can be regarded as containing the polymer component (A) and the thermosetting component (B).

[Thermosetting component (B)]

The thermosetting component (B) is a component for forming a hard protective film by hardening the film for thermosetting protective film formation.

The composition (III-1) for forming a protective film and the thermosetting component (B) contained in the film for forming a thermosetting protective film may be one type or two or more. above; in the case of two or more types, the combination and ratio of these can be arbitrarily selected.

As the thermosetting component (B), for example, epoxy-based thermosetting resins, thermosetting polyimides, polyurethanes, unsaturated polyesters, polysiloxane resins, etc. may be mentioned, and preferably Epoxy thermosetting resin.

(Epoxy thermosetting resin)

The epoxy-based thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2).

The epoxy-based thermosetting resin contained in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may be only one type or two or more types; in the case of two or more types , the combination and ratio of these can be arbitrarily selected.

‧Epoxy resin (B1)

As epoxy resin (B1), well-known epoxy resins are mentioned, for example, polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydrogenated products, o-cresol novolak epoxy resins are mentioned. Resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin, etc. compound.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group can also be used. The epoxy resin having an unsaturated hydrocarbon group has higher compatibility with the acrylic resin than the epoxy resin having no unsaturated hydrocarbon group. Therefore, by using the epoxy resin which has an unsaturated hydrocarbon group, the reliability of the package obtained using the composite sheet for protective film formation improves.

As an epoxy resin which has an unsaturated hydrocarbon group, the compound which replaced some epoxy groups of a polyfunctional epoxy resin with the group which has an unsaturated hydrocarbon group is mentioned, for example. Such a compound is obtained, for example, by subjecting (meth)acrylic acid or a derivative thereof to an addition reaction with an epoxy group.

Moreover, as an epoxy resin which has an unsaturated hydrocarbon group, the compound etc. which the group which has an unsaturated hydrocarbon group couple|bonded directly with the aromatic ring etc. which comprise an epoxy resin are mentioned, for example.

The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples of the unsaturated hydrocarbon group include ethylene (vinyl), 2-propenyl (allyl), (meth)acryloyl, A (meth)acrylamido group or the like is preferably an acrylamide group.

In addition, in this specification, the "derivative" means a compound in which one or more hydrogen atoms of the original compound are substituted by groups (substituents) other than hydrogen atoms.

The number average molecular weight of the epoxy resin (B1) is not particularly limited, but is preferably 300 to 30,000 in terms of the curability of the film for forming a thermosetting protective film, and the strength and heat resistance of the protective film after curing. , more preferably 300 to 10,000, preferably 300 to 3,000.

The epoxy equivalent of the epoxy resin (B1) is preferably from 100 g/eq to 1100 g/eq, more preferably from 150 g/eq to 1000 g/eq.

One type of epoxy resin (B1) may be used alone, or two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio of these can be arbitrarily selected.

‧Thermosetting agent (B2)

The thermosetting agent (B2) functions as a curing agent for the epoxy resin (B1).

As a thermosetting agent (B2), the compound which has two or more functional groups which can react with an epoxy group in 1 molecule is mentioned, for example. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and an acid group formed by an anhydride, and preferably a phenolic hydroxyl group, an amino group, or an acid group formed by an anhydride. The base formed is more preferably a phenolic hydroxyl group or an amine group.

Among the thermosetting agents (B2), examples of the phenol-based curing agent having a phenolic hydroxyl group include polyfunctional phenol resins, biphenols, novolak-type phenol resins, dicyclopentadiene-based phenol resins, and aralkylphenols. resin, etc.

In a thermosetting agent (B2), as an amine type hardening agent which has an amine group, dicyandiamine (it may be abbreviated as "DICY" hereafter) etc. are mentioned, for example.

The thermal hardener (B2) may have an unsaturated hydrocarbon group.

Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include a compound in which a part of the hydroxyl groups of a phenol resin is substituted with a group having an unsaturated hydrocarbon group, and a group having an unsaturated hydrocarbon group directly bonded to the aromatic ring of the phenol resin. Compounds, etc.

The aforementioned unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the above-mentioned epoxy resin having an unsaturated hydrocarbon group.

In the case of using a phenol-based hardener as the thermal hardener (B2), the thermal hardener (B2) is preferably a phenol having a high softening point or glass transition temperature from the viewpoint of improving the peelability of the protective film from the support sheet. System hardener.

The thermosetting agent (B2) is preferably solid at room temperature and exhibits no hardening activity to the epoxy resin (B1); on the other hand, it dissolves by heating and exhibits a hardening activity to the epoxy resin (B1). Thermosetting agent (Hereinafter, it may be abbreviated as "thermally active latent epoxy resin curing agent").

The aforementioned thermally active latent epoxy resin hardener is stably dispersed in the epoxy resin (B1) in the film for thermosetting protective film formation at room temperature, but is compatible with the epoxy resin (B1) by heating, and Reacts with epoxy resin (B1). The storage stability of the composite sheet for protective film formation is remarkably improved by using the said thermally active latent epoxy resin hardener. For example, the transfer of the curing agent from the film for forming a protective film to the adjacent support sheet can be suppressed, and the reduction in the thermosetting properties of the film for forming a thermosetting protective film can be effectively suppressed. Moreover, since the film for thermosetting protective film formation becomes high thermosetting degree by heating, the pick-up property of the semiconductor wafer with a protective film mentioned later improves further.

As said thermally active latent epoxy resin hardener, an onium salt, a dibasic acid hydrazide, dicyandiamine, an amine adduct of a hardener, etc. are mentioned, for example.

In the thermosetting agent (B2), the number average molecular weight of resin components such as polyfunctional phenol resin, novolak-type phenol resin, dicyclopentadiene-based phenol resin, aralkylphenol resin, etc. is preferably 300 to 30,000, more preferably 400 to 10,000, more preferably 500 to 3,000.

In the thermosetting agent (B2), for example, the molecular weight of non-resin components such as biphenol and dicyandiamine is not particularly limited, but is preferably 60 to 500, for example.

A thermosetting agent (B2) may be used individually by 1 type, and may use 2 or more types together, and when using 2 or more types together, the combination and ratio of these can be selected arbitrarily.

In the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film, the content of the thermosetting agent (B2) is preferably 0.1 part by mass relative to 100 parts by mass of the content of the epoxy resin (B1). to 500 parts by mass, more preferably 1 to 200 parts by mass. When the said content of a thermosetting agent (B2) is more than the said lower limit, the film for thermosetting protective film formation becomes more easy to harden. Moreover, when the said content of the thermosetting agent (B2) is below the said upper limit, the moisture absorption rate of the film for thermosetting protective film formation falls, and the reliability of the package obtained using the composite sheet for protective film formation is further improved .

In the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2) ) relative to 100 parts by mass of the content of the polymer component (A), preferably 1 to 100 parts by mass, more preferably 1.5 to 85 parts by mass, particularly preferably 2 to 70 parts by mass. When the said content of a thermosetting component (B) is such a range, the adhesive force of a protective film and a support sheet is suppressed, and the peelability of a support sheet improves.

[Hardening accelerator (C)]

The composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the protective film-forming composition (III-1).

As preferable hardening accelerator (C), for example, tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol, etc. can be mentioned; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5- Imidazoles such as hydroxymethylimidazole (imidazoles in which one or more hydrogen atoms are substituted by groups other than hydrogen atoms); organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine (one or more A phosphine in which a hydrogen atom is replaced by an organic group); tetraphenyl boron salts such as tetraphenyl phosphonium tetraphenyl borate, triphenyl phosphine tetraphenyl borate, etc.

The composition for forming a protective film (III-1) and the curing accelerator (C) contained in the film for forming a thermosetting protective film may be only one type or two or more types; in the case of two or more types , the combination and ratio of these can be arbitrarily selected.

When the curing accelerator (C) is used, in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film, the content of the curing accelerator (C) is relative to the thermosetting component (B) ) content of 100 parts by mass, preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass. When the said content of a hardening accelerator (C) is more than the said lower limit, the remarkable effect by using a hardening accelerator (C) can be obtained. In addition, when the content of the curing accelerator (C) is below the above-mentioned upper limit value, for example, the highly polar curing accelerator (C) is suppressed from reacting with the film for forming a thermosetting protective film under high temperature and high humidity conditions. The effect of the adhesive body being transferred to the interface side and segregating becomes high, and the reliability of the package obtained by using the composite sheet for forming a protective film is further improved.

[filler (D)]

The composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may contain a filler (D). When the film for forming a thermosetting protective film contains the filler (D), the protective film obtained by curing the film for forming a thermosetting protective film becomes easy to adjust the coefficient of thermal expansion, and by making the coefficient of thermal expansion affect the formation of the protective film It is most suitable for the object, and the reliability of the package obtained by using the composite sheet for forming a protective film is further improved. In addition, by The film for thermosetting protective film formation contains a filler (D), and can also reduce the moisture absorption rate of a protective film, or improve heat dissipation.

The filler (D) may be any one of an organic filler and an inorganic filler, preferably an inorganic filler.

As preferred inorganic fillers, for example, powders of silica, alumina, talc, calcium carbonate, titanium dioxide, iron dan, silicon carbide, boron nitride, etc. can be mentioned; these inorganic fillers are spherical Beads; surface modification products of these inorganic fillers; single crystal fibers of these inorganic fillers; glass fibers, etc.

Among these, the inorganic filler is preferably silica or alumina.

The filler (D) contained in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may be only one type or two or more types; in the case of two or more types, the The combination and ratio of these can be arbitrarily selected.

When the filler (D) is used, in the composition (III-1) for forming a protective film, the content of the filler (D) (that is, the filler (D) in the film for forming a thermosetting protective film) The ratio of the content) to the total content of all components other than the solvent is preferably 5 to 80% by mass, more preferably 7 to 60% by mass. When the content of the filler (D) is in such a range, it becomes easier to adjust the thermal expansion coefficient.

[Coupling agent (E)]

The composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may contain a coupling agent (E). By using the compound which has a functional group which can react with an inorganic compound or an organic compound as a coupling agent (E), the adhesiveness and adhesiveness of the film for thermosetting protective film formation with respect to a to-be-adhered body can be improved. Moreover, by using a coupling agent (E), the water resistance improves without impairing the heat resistance of the protective film obtained by hardening the film for thermosetting protective film formation.

The coupling agent (E) is preferably a compound having a functional group capable of reacting with functional groups possessed by the polymer component (A), the thermosetting component (B), and the like, and is more preferably a silane coupling agent.

Examples of preferable silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyl Triethoxysilane, 3-glycidoxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethyl Oxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propylmethyl Diethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane Oxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfide, methyltrimethoxysilane, methyltriethoxysilane, ethylene trimethoxysilane, vinyltriacetoxysilane, imidazolylsilane, etc.

The coupling agent (E) contained in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may be only one type or two or more types; in the case of two or more types, the The combination and ratio of these can be arbitrarily selected.

In the case of using the coupling agent (E), in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film, the content of the coupling agent (E) is relative to the polymer component (A) and the heat The total content of the curable component (B) is 100 parts by mass, preferably 0.03 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, and particularly preferably 0.1 to 5 parts by mass. By the above-mentioned content of the coupling agent (E) being more than the above-mentioned lower limit value, the following effect brought about by the use of the coupling agent (E) can be obtained more significantly: the dispersibility of the filler (D) in the resin is improved, or The adhesion between the film for forming a thermosetting protective film and the adherend is improved, etc. Moreover, when the said content of a coupling agent (E) is below the said upper limit, generation|occurrence|production of outgas can be suppressed further.

[Crosslinker (F)]

In the case of using the above-mentioned acrylic resins having functional groups that can bond with other compounds, such as vinyl groups, (meth)acryloyl groups, amine groups, hydroxyl groups, carboxyl groups, isocyanate groups, etc., as the polymer component (A) In this case, the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may contain a crosslinking agent (F) for bonding the above-mentioned functional groups to other compounds. junction and cross-linking. The initial adhesion force and cohesion force of the film for thermosetting protective film formation can be adjusted by crosslinking using the crosslinking agent (F).

Examples of the crosslinking agent (F) include organic polyvalent isocyanate compounds, organic polyvalent imine compounds, metal chelate-based crosslinking agents (crosslinking agents having a metal chelate structure), and aziridine-based crosslinking agents. agent (crosslinking agent with aziridine group), etc.

Examples of the organic polyvalent isocyanate compound include: aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, and alicyclic polyvalent isocyanate compounds (hereinafter, these compounds may be collectively referred to as "aromatic polyvalent isocyanate compounds, etc."); Trimers, isocyanurate compounds, and adducts of the aforementioned aromatic polyvalent isocyanate compounds, etc.; terminal isocyanate urethane prepolymers, etc. obtained by reacting the aforementioned aromatic polyvalent isocyanate compounds, etc. with a polyol compound, etc. . The aforementioned "adduct" means the aforementioned aromatic polyisocyanate compound, aliphatic polyisocyanate compound or alicyclic polyisocyanate compound, which is mixed with ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil, etc. As an example of the above-mentioned adduct as the reactant of the low-molecular-weight active hydrogen compound, a xylylene diisocyanate adduct of trimethylolpropane, which will be described later, and the like are mentioned. In addition, the so-called "terminated isocyanate urethane prepolymer" is as described above.

As said organic polyvalent isocyanate compound, more specifically, 2, 4- toluene diisocyanate; 2, 6- toluene diisocyanate; 1, 3- xylylene diisocyanate; 1, 4- xylene diisocyanate are mentioned, for example Isocyanate; Diphenylmethane-4,4'-diisocyanate; Diphenylmethane-2,4'-diisocyanate; 3-Methyldiphenylmethane diisocyanate; Hexamethylene diisocyanate; Isophorone diisocyanate; Dicyclohexylmethane-4,4'-diisocyanate; Dicyclohexylmethane-2,4'-diisocyanate ; Compounds obtained by adding any one or more of toluene diisocyanate, hexamethylene diisocyanate and xylylene diisocyanate to all or part of the hydroxyl groups of polyols such as trimethylolpropane; lysine Acid diisocyanate, etc.

As said organic polyvalent imine compound, for example, N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), trimethylolpropane-tri-β-nitrogen Propidyl propionate, tetramethylolmethane-tri-beta-aziridinyl propionate, N,N'-toluene-2,4-bis(1-aziridinecarboxamide) tris-ethyl melamine, etc.

When an organic polyvalent isocyanate compound is used as the crosslinking agent (F), it is preferable to use a hydroxyl group-containing polymer as the polymer component (A). When the crosslinking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, the crosslinking structure can be easily introduced to the In the film for thermosetting protective film formation.

The crosslinking agent (F) contained in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may be only one type or two or more types; in the case of two or more types , the combination and ratio of these can be arbitrarily selected.

In the case of using a crosslinking agent (F), the composition for forming a protective film In (III-1), the content of the crosslinking agent (F) is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass relative to 100 parts by mass of the content of the polymer component (A). , particularly preferably 0.5 to 5 parts by mass. When the said content of a crosslinking agent (F) is more than the said lower limit, the effect by using a crosslinking agent (F) is more remarkable. Moreover, since the said content of the crosslinking agent (F) is below the said upper limit, the adhesive force of the film for thermosetting protective film formation and the support sheet, or the film for thermosetting protective film formation and the semiconductor wafer or the The adhesion of the semiconductor wafer is excessively reduced.

In the present embodiment, even if the crosslinking agent (F) is not used, the effect of the present invention can be sufficiently obtained.

[Energy beam curable resin (G)]

The composition (III-1) for forming a protective film may contain an energy ray curable resin (G). Since the film for thermosetting protective film formation contains an energy ray curable resin (G), it can change a characteristic by irradiating an energy ray.

The energy ray curable resin (G) is obtained by polymerizing (hardening) an energy ray curable compound.

As said energy-beam curable compound, the compound which has at least 1 polymerizable double bond in a molecule|numerator is mentioned, for example, Preferably it is an acrylate type compound which has a (meth)acryloyl group.

As said acrylate type compound, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylic acid are mentioned, for example ester, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol dimethacrylate (Meth)acrylate, 1,6-hexanediol di(meth)acrylate, etc. (meth)acrylate containing chain aliphatic skeleton; Dicyclopentyl di(meth)acrylate, etc. (Meth)acrylate of aliphatic skeleton; Polyalkylene glycol (meth)acrylate such as polyethylene glycol di(meth)acrylate; Oligoester (meth)acrylate; (Meth)acrylic acid Urethane oligomers; Epoxy modified (meth)acrylates; Polyether (meth)acrylates other than the aforementioned polyalkylene glycol (meth)acrylates; Itaconic acid oligomers Wait.

The weight average molecular weight of the aforementioned energy ray curable compound is preferably from 100 to 30,000, more preferably from 300 to 10,000.

Only one type of the above-mentioned energy ray-curable compound used for polymerization may be used, or two or more types may be sufficient; in the case of two or more types, the combination and ratio of these may be arbitrarily selected.

The energy ray curable resin (G) contained in the composition (III-1) for forming a protective film may be only one type or two or more types; in the case of two or more types, the combination and ratio of these may be Arbitrary choice.

In the composition (III-1) for forming a protective film, the content of the energy ray-curable resin (G) is preferably 1 to 95% by mass, more preferably 2 to 90% by mass, particularly preferably 3% by mass % to 85% by mass.

[Photopolymerization initiator (H)]

When the protective film-forming composition (III-1) contains the energy ray-curable resin (G), a photopolymerization initiator may be contained in order to allow the energy ray-curable resin (G) to efficiently carry out the polymerization reaction (H).

As the photopolymerization initiator (H) in the composition (III-1) for forming a protective film, the same compound as the photopolymerization initiator in the adhesive composition (ii) can be mentioned.

The photopolymerization initiator (H) contained in the composition (III-1) for forming a protective film may be only one type or two or more types; in the case of two or more types, the combination and ratio of these may be Arbitrary choice.

In the case of using a photopolymerization initiator (H), in the protective film-forming composition (III-1), the content of the photopolymerization initiator (H) is 100 relative to the content of the energy ray-curable resin (G) The mass part is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, particularly preferably 2 to 5 parts by mass.

[Colorant (I)]

The composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may contain a colorant (I).

As a coloring agent (I), well-known coloring agents, such as an inorganic type pigment, an organic type pigment, and an organic type dye, are mentioned, for example.

Examples of the organic pigments and organic dyes include ammonium-based dyes, cyanine-based dyes, merocyanine-based dyes, croconium-based dyes, squalilium-based dyes, and azulium-based dyes. Pigments, polymethine based pigments, naphthoquinone based pigments, pyrylium based pigments, phthalocyanine based pigments, naphthalocyanine based pigments, naphthalamide based pigments, azo pigments, condensed azo pigments, indigo based pigments , Perinone dyes, perylene dyes, dioxane dyes, quinacridone dyes, isoindolinone dyes, quinophthalone dyes, pyrrole dyes , thioindigo-based dyes, metal complex dyes (metal salt dyes), dithiol metal complex dyes, indoxyl dyes, triallylmethane dyes, anthraquinone dyes, naphthalene Phenol-based dyes, methine azo-based dyes, benzimidazolone-based dyes, picanthrone-based dyes, threne-based dyes, and the like.

Examples of the inorganic pigments include carbon black, cobalt-based pigments, iron-based pigments, chromium-based pigments, titanium-based pigments, vanadium-based pigments, zirconium-based pigments, molybdenum-based pigments, ruthenium-based pigments, platinum-based pigments, and ITO. (Indium Tin Oxide; indium tin oxide)-based dye, ATO (Antimony Tin Oxide; antimony tin oxide)-based dye, and the like.

The coloring agent (I) contained in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may be only one kind or two or more kinds; in the case of two or more kinds, The combination and ratio of these can be arbitrarily selected.

When using a coloring agent (I), content of the coloring agent (I) in the film for thermosetting protective film formation may be adjusted suitably according to the objective. For example, printing may be performed on the protective film by laser irradiation, and by adjusting the content of the colorant (I) in the film for forming a thermosetting protective film, the light transmittance of the protective film may be adjusted, and the visibility of the printing may be adjusted. In addition, by adjusting the content of the colorant (I) in the film for forming a thermosetting protective film, the designability of the protective film can be improved, and the grinding traces on the back surface of the semiconductor wafer can be made less visible. Considering this aspect, in the composition (III-1) for forming a protective film, the content of the coloring agent (I) (that is, the content of the coloring agent (I) in the film for forming a thermosetting protective film) is relatively The ratio of the total content of all components other than the solvent is preferably 0.1 to 10% by mass, more preferably 0.1 to 7.5% by mass, and still more preferably 0.1 to 5% by mass. When the aforementioned content of the colorant (I) is more than the aforementioned lower limit value, a more significant effect by using the colorant (I) can be obtained. Moreover, when the said content of a coloring agent (I) is below the said upper limit, it can suppress that the light transmittance of the film for thermosetting protective film formation falls too much.

[General Additives (J)]

The composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may contain a general-purpose additive (J) within a range that does not impair the effect of the present invention.

The general-purpose additive (J) may be a known additive, and can be arbitrarily selected according to the purpose without particular limitation. As the preferred general-purpose additive (J), for example, a plasticizer, an antistatic agent, an antioxidant, and a getter can be mentioned. (gettering agent), etc.

The general additive (I) contained in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film may be only one kind or two or more kinds; in the case of two or more kinds, the The combination and ratio of these can be arbitrarily selected.

The content of the general-purpose additive (I) in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film is not particularly limited, and may be appropriately selected according to the purpose.

[solvent]

The protective film-forming composition (III-1) preferably further contains a solvent. The solvent-containing composition for forming a protective film (III-1) has good handleability.

The aforementioned solvent is not particularly limited, and preferable examples of the aforementioned solvent include hydrocarbons such as toluene and xylene; methanol, ethanol, 2-propanol, isobutanol (2-methylpropan-1-ol), 1 - alcohols such as butanol; esters such as ethyl acetate and butyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amine bond compound) and so on.

The solvent contained in the composition (III-1) for forming a protective film may be only one type or two or more types, and in the case of two or more types, the combination and ratio of these may be arbitrarily selected.

The solvent contained in the composition for forming a protective film (III-1) is preferably methyl ethyl ketone, since the components contained in the composition for forming a protective film (III-1) can be mixed more uniformly Wait.

<<The manufacturing method of the composition for thermosetting protective film formation>>

The composition for forming a thermosetting protective film, such as the composition for forming a protective film (III-1), is obtained by blending each component constituting the composition.

The order of addition at the time of preparing each component is not particularly limited, and two or more components may be added at the same time.

In the case of using a solvent, it can be used by mixing the solvent with any preparation component other than the solvent and diluting the preparation component in advance; it can also be used in the following way: not using any preparation component other than the solvent The formulating ingredients are pre-diluted and the solvent is mixed with these formulating ingredients.

The method of mixing the components during the preparation is not particularly limited, and may be appropriately selected from the following well-known methods: a method of mixing by rotating a stirring bar or a stirring blade, a method of mixing using a mixer, and a method of applying ultrasonic waves for mixing method etc.

The temperature and time at the time of adding and mixing each component are not particularly limited as long as each compounded component is not degraded, and may be appropriately adjusted, and the temperature is preferably 15°C to 30°C.

‧Film for forming energy ray curable protective film

The film for energy ray curable protective film formation contains an energy ray curable component (a).

The energy ray curable component (a) is preferably uncured, preferably has adhesiveness, and is more preferably uncured and has adhesiveness. Here, the so-called "energy ray" and "energy ray sclerosis" are as described above.

<<The composition for forming an energy ray curable protective film>>

The film for energy ray curable protective film formation can be formed using the composition for energy ray curable protective film formation containing the constituent material of the film. For example, the composition for forming an energy ray curable protective film can be applied to the surface to be formed of the film for forming an energy ray curable protective film, and then dried if necessary, whereby the composition for forming an energy ray curable protective film can be formed at the target site. membrane. The content ratio of the components which do not vaporize at normal temperature in the composition for energy ray curable protective film formation is usually the same as the content ratio of the aforementioned components in the film for energy ray curable protective film formation. Here, the so-called "normal temperature" is as described above.

The composition for forming an energy ray-curable protective film may be applied by a known method, and examples thereof include methods using the following various coaters: air knife coater, blade coater, bar coater, gravure coater Cloth machine, roll coater, roll knife coater, curtain coater, die coater, knife coater, screen coater, wire rod coater, contact coater Cloth machine, etc.

The drying conditions of the composition for forming an energy ray curable protective film are not particularly limited, and the composition for forming an energy ray curable protective film contains the composition described later. In the case of a solvent, drying by heating is preferably performed, and in this case, drying is preferably performed under the conditions of, for example, 70° C. to 130° C. for 10 seconds to 5 minutes.

<Protection film-forming composition (IV-1)>

Examples of the energy-ray-curable protective film-forming composition include the energy-ray-curable protective film-forming composition (IV-1) (in this specification, it may be simply abbreviated as the energy ray curable component (a)), for example. "Protection film-forming composition (IV-1)") and the like.

[energy ray sclerosing component (a)]

The energy ray-curable component (a) is a component converted by irradiation with energy rays, and this component is used to impart film-forming properties, flexibility, and the like to the film for energy ray-curable protective film formation.

Examples of the energy ray curable component (a) include a polymer (a1) having an energy ray curable group and a weight average molecular weight of 80,000 to 2,000,000, and a compound having an energy ray curable group and a molecular weight of 100 to 80,000. (a2). At least a part of the said polymer (a1) may be crosslinked by a crosslinking agent, and may not be crosslinked.

(Polymer (a1) having an energy ray hardening group and having a weight average molecular weight of 80,000 to 2,000,000)

Examples of the polymer (a1) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2,000,000 include an acrylic resin (a1-1) which is an acrylic polymer (a1-1). a11) Formed by addition reaction with an energy ray curable compound (a12), the acrylic polymer (a11) having a functional group reactive with a group of other compounds, the energy ray curable compound (a12) having the same Energy ray hardening groups such as functional groups reacting groups and energy ray hardening double bonds.

Examples of the functional group that can react with groups contained in other compounds include a hydroxyl group, a carboxyl group, an amino group, and a substituted amino group (a group in which one or two hydrogen atoms of the amino group are substituted with a group other than a hydrogen atom). group), epoxy group, etc. However, it is preferable that the said functional group is a group other than a carboxyl group from the viewpoint of preventing circuit corrosion of a semiconductor wafer, a semiconductor wafer, or the like.

Among these, the aforementioned functional group is preferably a hydroxyl group.

‧Acrylic polymer with functional group (a11)

Examples of the functional group-containing acrylic polymer (a11) include, for example, a polymer obtained by copolymerizing the functional group-containing acrylic monomer and the non-functional group-containing acrylic monomer. A polymer obtained by copolymerizing monomers other than acrylic monomers (non-acrylic monomers) in addition to these monomers.

In addition, the aforementioned acrylic polymer (a11) may be a random copolymer or a block copolymer.

Examples of the functional group-containing acrylic monomer include hydroxyl group-containing monomers, carboxyl group-containing monomers, amine group-containing monomers, substituted amino group-containing monomers, epoxy group-containing monomers, and the like .

Examples of the hydroxyl group-containing monomer include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 3-hydroxypropyl (meth)acrylate. Hydroxyalkyl (meth)acrylates such as hydroxypropyl, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate; vinyl alcohol, Non-(meth)acrylic unsaturated alcohols such as allyl alcohol (unsaturated alcohols having no (meth)acryloyl skeleton), and the like.

Examples of the carboxyl group-containing monomer include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having an ethylenically unsaturated bond) such as (meth)acrylic acid and crotonic acid; fumaric acid, itaconic acid, Ethylenically unsaturated dicarboxylic acids (dicarboxylic acids with ethylenically unsaturated bonds) such as maleic acid and citraconic acid; anhydrides of the aforementioned ethylenically unsaturated dicarboxylic acids; 2-carboxyethyl methacrylate, etc. (methyl methacrylate) base) carboxyalkyl acrylate, etc.

The aforementioned acrylic monomer having a functional group is preferably a hydroxyl group-containing monomer, a carboxyl group-containing monomer, and more preferably a hydroxyl group-containing monomer.

The functional group-containing acrylic monomer constituting the acrylic polymer (a11) may be only one type or two or more types; in the case of two or more types, the combination and ratio of these may be arbitrarily selected.

Examples of the acrylic monomer having no functional group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate. ester, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-butyl (meth)acrylate, 3-butyl (meth)acrylate, amyl (meth)acrylate, (meth)acrylate (methyl)hexyl acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-octyl (meth)acrylate Nonyl ester, isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate) , tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, ten (meth)acrylate Hexaalkyl esters (palmityl (meth)acrylate), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate), etc. constitute alkyl esters The alkyl group is an alkyl (meth)acrylate having a chain structure of 1 to 18 carbon atoms.

Moreover, as an acryl-type monomer which does not have the said functional group, (meth)acrylate methoxymethyl, (meth)acrylate methoxyethyl, (meth)acrylate ethoxymethyl can also be mentioned, for example. (meth)acrylates containing alkoxyalkyl groups such as ethoxyethyl (meth)acrylates; aromatic groups containing aryl (meth)acrylates such as phenyl (meth)acrylates (meth)acrylate; non-crosslinkable (meth)acrylamide and its derivatives; (meth)acrylate N,N-dimethylaminoethyl ester, (meth)acrylate N,N- Non-crosslinkable (meth)acrylates having tertiary amine groups, such as dimethylaminopropyl ester, etc.

The acryl-based monomer that does not have a functional group constituting the acryl-based polymer (a11) may be only one type or two or more types; in the case of two or more types, the combination and ratio of these may be arbitrarily selected .

Examples of the non-acrylic monomers include olefins such as ethylene and norbornene; vinyl acetate; styrene and the like.

The said non-acrylic-type monomer which comprises the said acrylic polymer (a11) may be only 1 type, and may be 2 or more types; In the case of 2 or more types, the combination and ratio of these can be selected arbitrarily.

In the acrylic polymer (a11), the ratio (content) of the amount of the structural units derived from the functional group-containing acrylic monomer to the total amount of the structural units constituting the acrylic polymer (a11) is preferable It is 0.1 mass % to 50 mass %, More preferably, it is 1 mass % to 40 mass %, Especially preferably, it is 3 mass % to 30 mass %. By setting the ratio in this range, the acrylic resin (a1-1) obtained by the copolymerization of the acrylic polymer (a11) and the energy ray curable compound (a12) can be energy ray hardened The content of the radicals can be easily adjusted to a range in which the degree of hardening of the protective film is preferable.

The said acrylic polymer (a11) which comprises the said acrylic resin (a1-1) may be only 1 type, and may be 2 or more types; In the case of 2 or more types, the combination and ratio of these can be selected arbitrarily.

In the composition (IV-1) for forming a protective film, the content of the acrylic resin (a1-1) is preferably 1 to 40 mass %, more preferably 2 to 30 mass %, particularly preferably 3 mass % % to 20% by mass.

‧Energy ray curable compound (a12)

The aforementioned energy ray-curable compound (a12) preferably has one or more selected from the group consisting of an isocyanate group, an epoxy group, and a carboxyl group as a compound that the aforementioned acrylic polymer (a11) has. More preferably, the functional group reacts with an isocyanate group as the aforementioned group. When the energy ray-curable compound (a12) has, for example, an isocyanate group as the group, the isocyanate group easily reacts with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as a functional group.

It is preferable that the said energy ray hardening compound (a12) has 1 to 5 said energy ray hardening groups in 1 molecule, More preferably, it has 1 to 2 said energy ray hardening groups.

Examples of the energy ray curable compound (a12) include 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate, and methacryloyl isocyanate. diisocyanate, allyl isocyanate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate; by reaction of diisocyanate compound or polyisocyanate compound with hydroxyethyl (meth)acrylate Acryloyl monoisocyanate compound obtained; by diisocyanate Compounds or polyisocyanate compounds, polyol compounds and hydroxyethyl (meth)acrylate obtained by the reaction of acrylyl monoisocyanate compounds and the like.

Among these, it is preferable that the said energy ray curable compound (a12) is 2-methacryloyloxyethyl isocyanate.

The aforementioned energy ray-curable compound (a12) constituting the aforementioned acrylic resin (a1-1) may be only one type or two or more types; in the case of two or more types, the combination and ratio of these may be arbitrarily selected .

In the acrylic resin (a1-1), the ratio of the content of the energy ray curable group derived from the energy ray curable compound (a12) to the content of the functional group derived from the acrylic polymer (a11) It is preferably 20 mol% to 120 mol%, more preferably 35 mol% to 100 mol%, particularly preferably 50 mol% to 100 mol%. When the ratio of the said content is in such a range, the adhesive force of the protective film after hardening becomes further large. Furthermore, in the case where the energy ray-curable compound (a12) is a monofunctional (having one of the aforementioned groups in 1 molecule) compound, the upper limit of the ratio of the aforementioned content is 100 mol%, but in the aforementioned energy When the linear curable compound (a12) is a polyfunctional (having two or more of the aforementioned groups in one molecule) compound, the upper limit of the ratio of the aforementioned content may exceed 100 mol %.

The weight average molecular weight (Mw) of the aforementioned polymer (a1) is preferably from 100,000 to 2,000,000, more preferably from 300,000 to 1,500,000.

Here, the so-called "weight average molecular weight" is as described above.

When at least a part of the above-mentioned polymer (a1) is cross-linked by a cross-linking agent, the above-mentioned polymer (a1) may be any monomer constituting the above-mentioned acrylic polymer (a11) other than those described above and The monomer having a group reactive with the crosslinking agent is polymerized, and the crosslinking is performed in the group reactive with the crosslinking agent, or the group derived from the energy ray curable compound (a12) and the functional group reactive with the above-mentioned can also be carried out. cross-linking.

The above-mentioned polymer (a1) contained in the composition (IV-1) for forming a protective film and the film for forming an energy ray-curable protective film may be only one type or two or more types; in the case of two or more types , the combination and ratio of these can be arbitrarily selected.

(Compound (a2) having an energy ray hardening group and having a molecular weight of 100 to 80,000)

Examples of the energy-ray-curable group of the compound (a2) having an energy-ray-curable group and a molecular weight of 100 to 80,000 include groups containing an energy-ray-curable double bond; base) acrylyl, vinyl, etc.

The compound (a2) is not particularly limited as long as it satisfies the above-mentioned conditions, and examples thereof include a low molecular weight compound having an energy ray curable group, a compound having an energy Epoxy resin with a line curable group, phenol resin with an energy line curable group, etc.

In the said compound (a2), as a low molecular weight compound which has an energy ray hardening group, a polyfunctional monomer, an oligomer, etc. are mentioned, for example, Preferably it is an acrylate type compound which has a (meth)acryloyl group.

As said acrylate type compound, for example, 2-hydroxy-3-(meth)acryloyloxypropyl methacrylate, polyethylene glycol di(meth)acrylate, propoxylated ethoxy bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acrylooxypolyethoxy)phenyl]propane, ethoxylated bisphenol A di(methyl) ) acrylate, 2,2-bis[4-((meth)acryloyloxydiethoxy)phenyl]propane, 9,9-bis[4-(2-(meth)acryloyloxy) ethoxy) phenyl] stilbene, 2,2-bis[4-((meth)acryloyloxypolypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth)acrylate, 1 ,10-decanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate ) acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol Alcohol di(meth)acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[4-((meth)acrylooxyethoxy)phenyl]propane, neopentyl glycol Bifunctional (meth)acrylates such as alcohol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, 2-hydroxy-1,3-di(meth)acrylooxypropane, etc. ; Tris-(2-(meth)acryloyloxyethyl) isocyanurate, ε-caprolactone-modified tris-(2-(meth)acryloyloxyethyl) isocyanurate , ethoxylated glycerol tri(methyl) base) acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, di-trimethylolpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate base) acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, dipentaerythritol hexa(meth)acrylate and other polyfunctional (meth)acrylates; (meth)acrylate amino group Polyfunctional (meth)acrylate oligomers such as formate oligomers, etc.

Among the above-mentioned compounds (a2), as the epoxy resin having an energy ray-curable group and the phenol resin having an energy ray-curable group, for example, those described in paragraph 0043 of "Japanese Unexamined Patent Application Publication No. 2013-194102" can be used. of resin. Although such resin also corresponds to the resin which comprises the thermosetting component mentioned later, in this embodiment, it is regarded as said compound (a2).

The weight average molecular weight of the aforementioned compound (a2) is preferably from 100 to 30,000, more preferably from 300 to 10,000.

The above-mentioned compound (a2) contained in the composition (IV-1) for forming a protective film and the film for forming an energy ray-curable protective film may be only one type or two or more types; in the case of two or more types , the combination and ratio of these can be arbitrarily selected.

[Polymer (b) without energy ray curable group]

The composition (IV-1) for forming a protective film and the film for forming an energy ray curable protective film contain the compound (a2) as the energy ray curable composition. In the case of (a), it is preferable to further contain the polymer (b) which does not have an energy ray curable group.

At least a part of the said polymer (b) may be crosslinked by a crosslinking agent, and may not be crosslinked.

Examples of the polymer (b) not having an energy ray curable group include acrylic polymers, phenoxy resins, urethane resins, polyesters, rubber-based resins, and acrylic urethane resins. Wait.

Among these, the aforementioned polymer (b) is preferably an acrylic polymer (hereinafter, abbreviated as "acrylic polymer (b-1)" in some cases).

The acrylic polymer (b-1) may be a known polymer, for example, a homopolymer of one acrylic monomer, a copolymer of two or more acrylic monomers, or a single or A copolymer of two or more acrylic monomers and one or more monomers (non-acrylic monomers) other than acrylic monomers.

Examples of the aforementioned acrylic monomers constituting the acrylic polymer (b-1) include alkyl (meth)acrylates, (meth)acrylates having a cyclic skeleton, and (meth)acrylates having a glycidyl group. group) acrylate, hydroxyl group-containing (meth)acrylate, substituted amine group-containing (meth)acrylate, etc. Here, the so-called "substituted amino group" is as described above.

Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, (meth)acrylate n-butyl meth)acrylate, isobutyl (meth)acrylate, 2nd butyl (meth)acrylate, 3rd butyl (meth)acrylate, amyl (meth)acrylate, (meth)acrylic acid Hexyl ester, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, Isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), (meth)acrylate base) tridecyl acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, hexadecyl (meth)acrylate Ester (palmityl (meth)acrylate), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate), etc. It is a (meth)acrylic acid alkyl ester of a chain structure with a carbon number of 1 to 18, and the like.

Examples of (meth)acrylates having the aforementioned cyclic skeleton include cycloalkyl (meth)acrylates such as isobornyl (meth)acrylate and dicyclopentyl (meth)acrylate; ) Aralkyl acrylates such as benzyl acrylate; (meth) cycloalkenyl acrylates such as dicyclopentenyl (meth)acrylate; Dicyclopentenyloxyethyl (meth)acrylate, etc. (Meth)acrylic acid cycloalkenyloxyalkyl ester and the like.

Examples of the aforementioned glycidyl group-containing (meth)acrylate include, for example, Glycidyl (meth)acrylate etc. are mentioned.

Examples of the hydroxyl group-containing (meth)acrylate include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, (meth)acrylate ) 3-hydroxypropyl acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and the like.

As said substituted amino group containing (meth)acrylate, (meth)acrylate N-methylaminoethyl etc. are mentioned, for example.

As said non-acrylic-type monomer which comprises an acrylic-type polymer (b-1), olefin, such as ethylene and norbornene; vinyl acetate; styrene, etc. are mentioned, for example.

Examples of the polymer (b) that is at least partially cross-linked by a cross-linking agent and does not have the above-mentioned energy ray-curable group include polymerization in which the reactive functional group in the above-mentioned polymer (b) reacts with a cross-linking agent. thing.

The reactive functional group may be appropriately selected according to the type of the crosslinking agent and the like, and is not particularly limited. For example, when the crosslinking agent is a polyisocyanate compound, the reactive functional group includes a hydroxyl group, a carboxyl group, an amine group, and the like, and among these, a hydroxyl group having high reactivity with an isocyanate group is preferred. In addition, when the crosslinking agent is an epoxy-based compound, examples of the reactive functional group include a carboxyl group, an amino group, an amide group, and the like, and among these, the one with high reactivity with an epoxy group is preferred. carboxyl. However, to prevent semiconductors In terms of circuit etching of wafers or semiconductor chips, the reactive functional group is preferably a group other than a carboxyl group.

As a polymer (b) which has the said reactive functional group and does not have an energy ray hardening group, the polymer obtained by polymerizing at least the monomer which has the said reactive functional group is mentioned, for example. In the case of the acrylic polymer (b-1), either or both of the aforementioned acrylic monomers and non-acrylic monomers listed as the monomers constituting the acrylic polymer (b-1) , the monomer with the aforementioned reactive functional group can be used. For example, as the polymer (b) having a hydroxyl group as a reactive functional group, for example, a polymer obtained by polymerizing a hydroxyl group-containing (meth)acrylate can be mentioned. A polymer obtained by polymerizing a monomer in which one or two or more hydrogen atoms of the aforementioned acrylic monomers or non-acrylic monomers are substituted with the aforementioned reactive functional groups.

In the aforementioned polymer (b) having a reactive functional group, the ratio (content) of the amount of the structural unit derived from the monomer having a reactive functional group to the total amount of the structural units constituting the polymer (b) is relatively Preferably it is 1 mass % - 20 mass %, More preferably, it is 2 mass % - 10 mass %. Since the said ratio is such a range, in the said polymer (b), the degree of crosslinking becomes a more preferable range.

The weight average molecular weight (Mw) of the polymer (b) not having an energy ray-curable group is preferably from 10,000 to 2,000,000 in terms of better film-forming properties of the protective film-forming composition (IV-1), More preferably 100000 to 1500000. Here, the so-called "weight average molecular weight" is as described above.

The composition for forming a protective film (IV-1) and the film for forming an energy ray curable protective film may contain only one polymer (b) without an energy ray curable group, or two or more kinds; In the case of two or more types, the combination and ratio of these can be arbitrarily selected.

As the composition (IV-1) for forming a protective film, a composition containing either or both of the above-mentioned polymer (a1) and the above-mentioned compound (a2) can be mentioned. In addition, when the composition (IV-1) for forming a protective film contains the aforementioned compound (a2), it is preferable to further contain a polymer (b) having no energy ray curable group, and in this case, it is also preferable It is preferable to further contain the said (a1). Moreover, the composition (IV-1) for forming a protective film may not contain the said compound (a2), and may contain the said polymer (a1) and the polymer (b) which does not have an energy ray curable group together.

When the composition (IV-1) for forming a protective film contains the polymer (a1), the compound (a2), and the polymer (b) without an energy ray curable group, the composition for forming a protective film ( In IV-1), the content of the aforementioned compound (a2) is preferably 10 to 400 parts by mass relative to 100 parts by mass of the total content of the aforementioned polymer (a1) and the polymer (b) having no energy ray hardening group parts by mass, more preferably 30 parts by mass to 350 parts by mass.

In the composition (IV-1) for forming a protective film, the total content of the energy ray curable component (a) and the polymer (b) having no energy ray curable group (that is, the energy ray curable protective film forming The ratio of the total content of the aforementioned energy ray-curable component (a) and the polymer (b) having no energy ray-curable group) to the total content of components other than the solvent in the film is preferably 5% by mass to 90% by mass. The mass % is more preferably 10 to 80 mass %, particularly preferably 20 to 70 mass %. When the said ratio of content of an energy ray curable component is such a range, the energy ray curability of the film for energy ray curable protective film formation becomes more favorable.

The composition (IV-1) for forming a protective film may contain, in addition to the above-mentioned energy ray curable component, a thermosetting component, a photopolymerization initiator, a filler, a coupling agent, and a crosslinking agent according to the purpose. , one or more of the group consisting of colorants and general additives. For example, by using the composition for forming a protective film (IV-1) containing the energy ray curable component and the thermosetting component, the formed film for forming an energy ray curable protective film is heated to the adherend. The adhesive force is improved, and the intensity|strength of the protective film formed from this film for energy-beam curable protective film formation is also improved.

Examples of the above-mentioned thermosetting components, photopolymerization initiators, fillers, coupling agents, crosslinking agents, colorants, and general additives in the composition (IV-1) for forming a protective film include: Thermosetting component (B), photopolymerization initiator (H), filler (D), Coupling agent (E), crosslinking agent (F), colorant (I) and general additive (J) are the same compounds.

In the composition (IV-1) for forming a protective film, the aforementioned thermosetting components, photopolymerization initiators, fillers, coupling agents, crosslinking agents, colorants and general additives may be used alone or in combination. When two or more types are used in combination, the combination and ratio of these can be arbitrarily selected.

The contents of the aforementioned thermosetting components, photopolymerization initiators, fillers, coupling agents, crosslinking agents, colorants and general additives in the composition (IV-1) for forming a protective film may be appropriately adjusted according to the purpose, and There is no particular limitation.

It is preferable that the composition for protective film formation (IV-1) further contains a solvent in order to improve the handleability of this composition by dilution.

As a solvent contained in the composition (IV-1) for forming a protective film, for example, the same solvent as the solvent in the composition (III-1) for forming a protective film can be mentioned.

The solvent contained in the composition (IV-1) for forming a protective film may be only one type or two or more types.

<<The manufacturing method of the composition for energy ray curable protective film forming>>

The composition for energy ray-curable protective film formation, such as the composition for protective film formation (IV-1), can be obtained by mixing each component which comprises this composition.

The order of addition of the ingredients is not particularly limited, and they may be added at the same time. Add 2 or more ingredients.

In the case of using a solvent, it can be used by mixing the solvent with any preparation component other than the solvent and diluting the preparation component in advance; it can also be used in the following way: not using any preparation component other than the solvent The formulating ingredients are pre-diluted and the solvent is mixed with these formulating ingredients.

The method of mixing the components during the preparation is not particularly limited, and may be appropriately selected from the following well-known methods: a method of mixing by rotating a stirring bar or a stirring blade, a method of mixing using a mixer, and a method of applying ultrasonic waves for mixing method etc.

The temperature and time at the time of adding and mixing each component are not particularly limited as long as each compounded component is not degraded, and may be appropriately adjusted, and the temperature is preferably 15°C to 30°C.

○Coating

The aforementioned coating layer is not particularly limited as long as the gloss value of the surface of the coating layer on the side opposite to the side in contact with the support sheet is 32 to 95.

As a preferable coating layer, for example, a coating composition containing a cured product obtained by curing by irradiation with energy rays is preferable, and a coating composition containing an energy-ray polymerizable compound polymerized by irradiation with energy rays is preferable. A coating obtained by hardening the material.

Further, the energy ray polymerizable compound is preferably (meth)acrylic acid or a derivative thereof.

The above-mentioned composite sheet for forming a protective film not only has the function of being formed to protect the back surface of the semiconductor wafer obtained by dicing, but also has the function of, for example, a dicing sheet when dicing the semiconductor wafer. In addition, when a semiconductor wafer is diced, the semiconductor wafer to which the composite sheet for forming a protective film is attached may be stretched; in this case, the composite sheet for forming a protective film is required to have moderate flexibility. In order to impart moderate flexibility to the composite sheet for forming a protective film, for example, a flexible resin such as polypropylene may be selected as a material constituting the support sheet. On the other hand, such a soft resin or the like may be deformed or wrinkled by heating. Therefore, it can be said that the coating layer is preferably formed by curing the composition used as the raw material by irradiating energy rays, not by thermal curing.

The thickness of the aforementioned coating layer is not particularly limited, but is preferably 0.1 μm to 20 μm, more preferably 0.4 μm to 15 μm, and particularly preferably 0.8 μm to 10 μm. By the thickness of the coating being more than the aforementioned lower limit value, the surface roughness Ra of the surface on the opposite side to the side in contact with the aforementioned support sheet in the coating becomes easier to reduce, further suppressing the aforementioned protective film forming composite sheet The effect of adhesion becomes higher. In addition, when the thickness of the coating layer is equal to or less than the upper limit value, a clearer inspection image can be obtained when the state of the semiconductor wafer to which the composite sheet for forming a protective film is attached is detected by an infrared camera or the like through the sheet. , which further makes it easier to dicing the semiconductor wafer along with the extension.

Furthermore, because the coating covers the concave-convex surface of the supporting sheet as described above, the contact surface with the supporting sheet can become the concave-convex surface; about the thickness of the coating, in the position of the convex portion in this concave-convex surface of the coating, The tip of the convex portion may be calculated as a common point.

The surface roughness Ra of the surface on the opposite side to the side in contact with the support sheet in the coating layer is preferably 0.5 μm or less, more preferably 0.4 μm or less, further preferably 0.3 μm or less, particularly preferably 0.2 μm the following. When the surface roughness Ra of the coating layer is equal to or less than the upper limit value, the protective film can be more clearly laser-printed.

In addition, the lower limit value of the surface roughness Ra of the surface on the opposite side to the side in contact with the support sheet in the coating layer is not particularly limited, and can be set to, for example, 0.005 μm or the like.

The aforementioned surface roughness Ra of the coating layer can be determined, for example, by the surface roughness Ra of the surface on the side with the coating layer in the support sheet, the thickness of the coating layer, the coating method of the coating composition described later for forming the coating layer, and the like. Make adjustments.

Regarding the aforementioned coating layer, the value of [the thickness of the coating layer (μm)]/[the surface roughness Ra (μm) of the surface on the side having the coating layer in the support sheet] is preferably from 0.1 to 30, more preferably from 0.3 to 30. 20, preferably 0.5 to 10. With the aforementioned value being above the aforementioned lower limit value, the surface roughness Ra of the surface on the opposite side to the side in contact with the aforementioned support sheet in the coating becomes smaller, and the protective film can be more clearly laser-printed, Furthermore, the effect of suppressing the blocking of the composite sheet for forming a protective film becomes higher. Moreover, since the said value is below the said upper limit, the thickness of a coating layer can be prevented from becoming too thick.

The gloss value of the surface of the opposite side is 32 to 95, preferably 40 to 90, with the side in contact with the aforementioned support sheet (the aforementioned support sheet side) in the aforementioned coating, More preferably, it is 45 to 85. When the aforementioned gloss value of the coating layer is in this range, the protective film can be more clearly laser-printed. Further, when the gloss value of the coating layer is equal to or greater than the lower limit value, when the state of the semiconductor wafer to which the composite sheet for forming a protective film is attached is detected by an infrared camera or the like through the sheet, a clearer detection can be obtained. image. In addition, when the gloss value of the coating layer is equal to or less than the upper limit value, when the state of the semiconductor wafer is similarly detected, the coating layer can be suppressed from shining, and the inspection image can be more easily recognized by an infrared camera or the like.

The measured value of the haze from the coating side of the composite sheet for forming a protective film is preferably 47% or less, more preferably 1% to 47%, further preferably 2% to 40%, particularly preferably 3% to 40%. 30%. Since the said haze of the composite sheet for protective film formation is below the said upper limit, scattering of light can be suppressed, and a protective film can be laser-printed more clearly. Further, when the state of the semiconductor wafer to which the composite sheet for forming a protective film is attached is detected by an infrared camera or the like via the sheet, a clearer inspection image can be obtained. Here, the measured value of the haze of the composite sheet for forming a protective film means that the composite sheet for forming a protective film is measured from the direction of the surface on the opposite side of the coating layer that is in contact with the support sheet. the haze value.

In addition, the said haze is the value obtained by measuring based on JISK7136.

Various properties such as the gloss value of the coating layer can be adjusted by, for example, the thickness of the coating layer, the components contained in the coating composition described later for forming the coating layer, and the like.

The measured value of the haze from the coating side of the composite sheet for forming a protective film can be determined by, for example, the thickness of each layer constituting the composite sheet for forming a protective film by a coating layer, a support sheet, or the like, and the composition for forming these layers (for example, , the components contained in the coating composition, which will be described later, are adjusted.

<<Coating composition>>

The coating composition is preferably one or both (α) (hereinafter, sometimes abbreviated as abbreviated as SiO 2 sol) and silica fine particles bound with an organic compound containing a radically polymerizable unsaturated group. "component (α)"), and at least one (β) selected from the group consisting of a polyfunctional acrylate-based monomer and an acrylate-based prepolymer (hereinafter, sometimes abbreviated as "component ( β)").

[Ingredient (α)]

The component (α) reduces the refractive index of the coating layer and reduces the curing shrinkage and heat-moisture shrinkage of the composite sheet for forming a protective film, thereby suppressing the occurrence of curling in the composite sheet for forming a protective film due to these shrinkages .

As the silica sol in the component (α), for example, colloidal silica can be mentioned, and the colloidal silica-based silica fine particles are derived from alcohol, It is formed by suspending in an organic solvent such as glycol ether (cellosolve) in a colloid state. The average particle size of the suspended silica particles is preferably 0.001 μm to 1 μm, more preferably 0.03 μm to 0.05 μm .

The silica fine particles in which the radically polymerizable unsaturated group-containing organic compound is bonded in the component (α) are cross-linked and cured by irradiation with energy rays.

Examples of the silica fine particles to which the radically polymerizable unsaturated group-containing organic compound is bound include, for example, silanol groups and radically polymerizable unsaturated group-containing organic compounds present on the surface of the silica fine particles. The particles formed by the reaction of the functional groups of the silica particles, the average particle size of the silica particles is preferably 0.005 μm to 1 μm. The functional group in the radically polymerizable unsaturated group-containing organic compound is not particularly limited as long as it can react with the silanol group in the silica fine particle.

As a radical polymerizable unsaturated group containing organic compound which has the said functional group, the compound etc. which are represented by following general formula (1) are mentioned, for example.

(In the formula, R ¹ is a hydrogen atom or a methyl group; R ² is a halogen atom or a group represented by any one of the following formulae (2a) to (2f))

As said halogen atom in R< ² >, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned, for example.

Examples of preferable radical-polymerizable unsaturated group-containing organic compounds include (meth)acrylic acid, (meth)acryloyl chloride, 2-isocyanatoethyl (meth)acrylate, (meth)acrylic acid, and (meth)acrylic acid. ) glycidyl acrylate, 2,3-iminopropyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, (3-(meth)acryloyloxypropyl)trimethoxysilane Wait.

In the present embodiment, the radically polymerizable unsaturated group-containing organic compound may be used alone or in combination of two or more.

In the component (α), the silica sol and the silica fine particles bound with the radically polymerizable unsaturated group-containing organic compound may each be only one type or two or more types.

As the component (α), only silica sol may be used, only the above-mentioned silica fine particles bound with an organic compound containing a radically polymerizable unsaturated group may be used, or a combination of silica sol and the above-mentioned bonding may be used. Silica microparticles containing organic compounds containing radically polymerizable unsaturated groups.

The content of the component (α) in the aforementioned coating composition is preferably selected according to the refractive index of the aforementioned support sheet, and usually the content of the silicon dioxide derived from the component (α) in the aforementioned coating layer is preferably 20 Mass % to 60 mass %. When the said content of silicon dioxide is more than the said lower limit, the effect of reducing the refractive index of a coating layer, and the effect of suppressing the generation|occurence|production of curl in the said composite sheet for protective film formation become high. In addition, by the above-mentioned content of silicon dioxide being equal to or less than the above-mentioned upper limit value, it becomes easier to form a coating layer, and the effect of suppressing a decrease in the hardness of the coating layer becomes higher.

The refractive index, ease of formation and hardness of the above-mentioned coating layer, and the property of suppressing the occurrence of curling in the composite sheet for forming a protective film are improved, and the content of the silicon dioxide derived from the component (α) in the coating layer More preferably, it is 20 mass % to 45 mass %.

[Ingredient (β)]

The said component (β) is the main photocurable component which forms the said coating layer.

The polyfunctional acrylate-based monomer in the component (β) is not particularly limited as long as it is a (meth)acrylic acid derivative having two or more (meth)acryloyl groups in one molecule.

As a preferable said polyfunctional acrylate type monomer, for example, 1, 4- butanediol di(meth)acrylate, 1, 6-hexanediol di(meth)acrylate, neopentyl Glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalate neopentyl glycol di(meth)acrylate, dicyclopentyl di(meth)acrylate, hexamethylene Lactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphoric acid di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate Di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid-modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate ) acrylate, propylene oxide modified trimethylolpropane tri(meth)acrylate, tris(acrylooxyethyl) isocyanurate, dipentaerythritol penta(meth)acrylate, propionic acid modified Sexual dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, caprolactone modified dipentaerythritol hexa(meth)acrylate, etc.

The acrylate-based prepolymer in the aforementioned component (β) is not particularly limited as long as it is a polymer or oligomer having photocurability using (meth)acrylate.

Examples of preferable acrylate-based prepolymers include polyester acrylate-based prepolymers, epoxy acrylate-based prepolymers, acrylic urethane-based prepolymers, and polyol acrylate-based prepolymers. prepolymer, etc.

As said polyester acrylate-based prepolymer, for example, a prepolymer obtained by a condensation reaction of a polyvalent carboxylic acid and a polyhydric alcohol can be mentioned: a polyester oligomer having hydroxyl groups at both ends of the molecule is obtained The hydroxyl group of the obtained polyester oligomer is esterified with (meth)acrylic acid; the oligomer is obtained by addition reaction of polyvalent carboxylic acid and alkylene oxide, and the obtained oligomer is obtained with (meth)acrylic acid The terminal hydroxyl esterification of the oligomer.

As said epoxy acrylate type prepolymer, the prepolymer obtained by, for example, a relatively low molecular weight bisphenol-type epoxy resin or a novolac-type epoxy resin of ethylene oxide can be mentioned. A ring (oxirane ring) reacts with (meth)acrylic acid and is esterified.

Examples of the aforementioned acrylic urethane-based prepolymer include prepolymers obtained by reacting polyether polyol or polyester polyol with polyisocyanate to obtain polyurethane The obtained polyurethane oligomer was esterified with (meth)acrylic acid.

As said polyol acrylate type prepolymer, the prepolymer obtained by esterifying the hydroxyl group of a polyether polyol with (meth)acrylic acid is mentioned, for example.

In the component (β), each of the multifunctional acrylate-based monomer and the acrylate-based prepolymer may be only one type, or two or more types may be used.

As the component (β), only the above-described polyfunctional acrylate-based monomer may be used, only the above-described acrylate-based prepolymer may be used, or the above-described polyfunctional acrylate-based monomer and acrylate-based prepolymer may be used in combination .

[solvent]

In addition to the component (α) and the component (β), the coating composition preferably further contains a solvent. When the coating composition contains a solvent, as will be described later, the coating composition can be more easily applied and dried to form a coating film for forming a coating layer.

The said solvent may be used individually by 1 type, and may use 2 or more types together.

Examples of the solvent include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as dichloromethane and dichloroethane; methanol, ethanol, and propanol. , butanol, 1-methoxy-2-propanol and other alcohols; acetone, methyl ethyl ketone, 2-pentanone, isophorone, cyclohexanone and other ketones; ethyl acetate, butyl acetate and other esters ; 2-ethoxyethanol (ethyl cellosolve) and other cellosolves.

[optional ingredient]

In addition to the component (α) and the component (β), the aforementioned coating composition may contain a monofunctional acrylate-based monomer, a photopolymerization initiator, a photosensitizer within the range that does not impair the effect of the present invention. Various optional ingredients such as agents, polymerization inhibitors, cross-linking agents, antioxidants, ultraviolet absorbers, light stabilizers, leveling agents, and antifoaming agents.

The said arbitrary components may be used individually by 1 type, and may use 2 or more types together.

(Monofunctional Acrylate Monomer)

The monofunctional acrylate-based monomer as an optional component is a photocurable component, and is not particularly limited as long as it is a (meth)acrylic derivative having only one (meth)acryloyl group in one molecule.

As a preferable said monofunctional acrylate type monomer, for example, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate ( (lauryl (meth)acrylate), octadecyl (meth)acrylate (stearyl (meth)acrylate), isobornyl (meth)acrylate, and the like.

(photopolymerization initiator)

As said photoinitiator of an arbitrary component, the well-known photoinitiator conventionally used for radical polymerization is mentioned.

Examples of preferable photopolymerization initiators include acetophenone-based compounds, benzophenone-based compounds, alkylaminobenzophenone-based compounds, benzoin-based compounds, benzoin-based compounds, and benzoin Aryl ketone-based photopolymerization initiators such as ether-based compounds, benzil dimethyl ketal-based compounds, benzyl benzoate-based compounds, and α-acyl oxime ester-based compounds; Sulfur-containing photopolymerization initiators such as xanthone-based compounds; acyl phosphine oxide-based compounds such as acyl diaryl phosphine oxide; anthraquinone-based compounds, and the like.

Furthermore, in the case where the coating composition is cured by irradiating an electron beam, a photopolymerization initiator is not required.

In the aforementioned coating composition, the content of the photopolymerization initiator is preferably 0.2 to 10 parts by mass, more preferably 0.5 to 7 parts by mass relative to 100 parts by mass of the total content of the photocurable components.

(photosensitizer)

As said photosensitizer, a tertiary amine, p-dimethylaminobenzoate, a thiol-type sensitizer etc. are mentioned, for example.

In the aforementioned coating composition, the content of the photosensitizer is preferably 1 to 20 parts by mass, more preferably 2 to 10 parts by mass relative to 100 parts by mass of the total content of the photocurable components.

(Antioxidants, UV Absorbers, Light Stabilizers)

The aforementioned antioxidants, ultraviolet absorbers and light stabilizers may be known compounds, but are preferably reactive antioxidants, ultraviolet absorbers, and light stabilizers having a (meth)acryloyl group or the like in the molecule. These antioxidants, ultraviolet absorbers, and light stabilizers are bonded to polymer chains formed by irradiating energy rays, so that they can be prevented from dissipating through the self-hardening layer over time, thereby exhibiting the functions of these components for a long period of time.

The coating composition preferably contains silica sol as the component (α), and more preferably contains silica sol having an average particle diameter of 0.03 μm to 0.05 μm suspended in a colloidal state.

By containing such a silica sol in the coating layer, the effect of suppressing the blocking of the composite sheet for forming a protective film becomes higher. In addition, in the above-mentioned coating, the silica sol is more present and segregated on the surface opposite to the support sheet side or in the vicinity thereof than other areas, thereby suppressing the above-mentioned protective film forming composite sheet. The effect of adhesion has become higher. In the coating layer, the coating conditions of the coating composition may be adjusted in order to make the components such as silica sol exist in a segregated manner.

<<Manufacturing method of coating composition>>

The coating composition can be obtained, for example, by using energy ray polymerizable compounds such as the component (α) and the component (β), and if necessary components other than these energy ray polymerizable compounds to constitute the coating composition. The components of the composition are adjusted. The coating composition can be obtained, for example, by the same method as in the case of the above-mentioned adhesive composition except that the composition is different.

In the case of using a solvent, it can be used by mixing the solvent with any preparation component other than the solvent and diluting the preparation component in advance; it can also be used in the following way: not using any preparation component other than the solvent The formulating ingredients are pre-diluted and the solvent is mixed with these formulating ingredients.

Components other than the solvent in the coating composition may be dissolved or dispersed without being dissolved. In addition, the concentration and viscosity of each component in the coating composition are not particularly limited as long as the coating composition can be applied.

◎Manufacturing method of the composite sheet for protective film formation

The composite sheet for forming a protective film according to the present embodiment can be produced by forming a film for forming a protective film using the composition for forming a protective film, forming a coating layer using the coating composition, and sequentially laminating the coating layer, A film for forming a support sheet and a protective film.

When the support sheet is composed of a plurality of layers, the support sheet may be produced by laminating these multiple layers. For example, when the support sheet is formed by laminating a base material and an adhesive, the adhesive layer may be formed using the above-mentioned adhesive composition.

The formation order of each layer (coating layer, a support sheet, and the film for protective film formation) which comprises the composite sheet for protective film formation is not specifically limited. Furthermore, when these layers are formed from the composition, they may be directly formed on the surfaces of the adjacent layers in the state of the composite sheet for forming a protective film, or a release film (release sheet) may be used separately, and a release film (release sheet) may be used separately on the surface of the release film (release sheet). It is formed on the surface, and this forming layer is bonded to the surface of the adjacent layer in the state of the composite sheet for forming a protective film. However, when the surface (back surface) on the opposite side to the surface (front surface) provided with the protective film forming film in the support sheet is a concave and convex surface, in order to suppress the uneven surface (back surface) between the coating layer and the support sheet It is preferable to form a coating layer by directly applying the coating composition on the uneven surface of the support sheet to generate voids.

Hereinafter, an example of a preferable manufacturing method of the composite sheet for protective film formation is demonstrated.

The coating is preferably formed by applying the coating composition on the concave-convex surface of the support sheet (the back side 10b of the support sheet 10 in FIG. 1 and FIG. 2 , that is, the back side 11b of the base material 11 ), and It is dried, and if necessary, the formed coating film is hardened.

The coating composition may be applied to the target surface by a known method, for example, methods using the following various coaters: air knife coater, knife coater, bar coater, gravure coater, Roll coater, roll knife coater, curtain coater, die coater, knife coater, screen coater, wire rod coater, contact coater, etc. .

When the coating composition is applied to the uneven surface of the support sheet, it is preferable to suppress the generation of voids between the coating layer and the uneven surface of the support sheet. By suppressing the generation of the aforementioned voids, diffuse reflection of light at the interface between the coating layer and the concave-convex surface of the support sheet can be suppressed, so that the surface of the protective film can be more clearly laser-printed.

In order to suppress the generation of the aforementioned voids, it is preferable to use, for example, a coating composition with a low viscosity. In addition, the coating composition containing the energy ray polymerizable compound is generally suitable for suppressing the generation of the aforementioned voids.

The drying conditions of the coating composition are not particularly limited, but the coating composition is preferably dried by heating. In this case, for example, drying is preferably performed under the conditions of 70°C to 130°C for 0.5 minutes to 5 minutes.

The curing conditions of the coating film formed from the coating composition are not particularly limited, and may be performed by a known method.

In the case of curing by irradiating energy rays, for example, when irradiating ultraviolet rays, a high-pressure mercury lamp, a fusion H-type lamp, or a xenon lamp is used as an ultraviolet source, and the irradiation amount is preferably set to 100mJ/cm ² to 500mJ/cm ² And it can be irradiated. On the other hand, when an electron beam is irradiated, an electron beam may be generated by an electron beam accelerator or the like, and the irradiation may be performed by setting the irradiation amount to preferably 150 kV to 350 kV. Among them, it is preferable to form a coating layer by irradiating ultraviolet rays.

For example, when the support sheet is formed by laminating a substrate and an adhesive, the adhesive layer can be directly applied and adhered to the surface of the substrate with the coating (the surface 11a of the substrate 11 in FIG. 1 and FIG. 2 ). formed by the composition of the agent. However, it is usually preferable to use the following method of separately forming an adhesive layer in advance and attaching the adhesive layer to the surface of the base material: for example, coating the adhesive composition on the peeling-treated surface of the release sheet and drying it, Thereby, an adhesive layer is formed, the formed adhesive layer is attached to the surface of the substrate, and the aforementioned release sheet is removed.

The adhesive composition can be applied to the object surface by the same method as in the case of applying the composition.

The applied adhesive composition may be cross-linked by heating, and the cross-linking by heating may be performed together with drying. The heating conditions can be set to, for example, 100° C. to 130° C. for 1 minute to 5 minutes, but are not limited thereto.

In any of the cases where the support sheet is composed of only one layer (single layer), such as the case where the support sheet is composed of a base material and an adhesive layer, and the case where the support sheet is composed of a plurality of layers, such as lamination of a base material and an adhesive The surface of the support sheet provided with the coating (the surface 10a of the support sheet 10 in FIG. 1 and FIG. 2, that is, the surface 12a of the adhesive layer 12) is directly coated with the composition for forming a protective film to form a film for forming a protective film. However, as in the case of the above-mentioned pressure-sensitive adhesive layer, it is generally preferable to employ the following method of separately forming a film for forming a protective film in advance and attaching the film for forming a protective film to the surface of the support sheet: peeling treatment on a peeling sheet The composition for forming a protective film is top-coated and dried to form a film for forming a protective film, the formed film for forming a protective film is bonded to the surface of the support sheet, and the release sheet is removed if necessary.

The composition for forming a protective film is applied to the target surface by the same method as in the case of applying the composition.

The drying conditions of the composition for forming a protective film are not particularly limited, and drying can be performed by the same method as in the case of coating the composition.

When the support sheet is formed by laminating a base material and an adhesive, the composite sheet for forming a protective film of the present embodiment can also be produced by a method other than the above-mentioned method. For example, a protective film shape can also be produced in the following manner A composite sheet for forming: an adhesive layer is formed using the above-mentioned adhesive composition, and a protective film-forming film is formed using the above-mentioned protective film-forming composition. The surface of the adhesive layer of this laminate (the surface of the adhesive layer on which the film for forming a protective film is not provided) is bonded to the surface of the substrate provided with the coating layer (surface 11a of the substrate 11 in FIGS. 1 and 2 ) .

In this case, the formation conditions of the adhesive layer and the film for forming a protective film are the same as those of the above-mentioned method.

In the case where the surface (back surface) opposite to the surface (surface) with the film for forming a protective film in the support sheet is a smooth surface and not a concave-convex surface, the composite sheet for forming a protective film of the present embodiment can also utilize the above-mentioned Manufactured by a method other than the method. For example, a composite sheet for forming a protective film may be produced by forming a coating layer using the above-mentioned coating composition, and attaching the coating layer to the smooth surface of the support sheet to obtain a laminate. On the other hand, use the aforementioned protective film forming composition to form a protective film forming film in advance, this protective film forming film is attached to the exposed surface of the support sheet in the aforementioned laminate (the coating is not provided in the support sheet) face). The composite sheet for forming a protective film can also be manufactured in the following manner, that is, the order of lamination of the pre-formed coating layer and the film for forming a protective film to the supporting sheet can also be opposite to the above, on one surface of the supporting sheet. After bonding the film for protective film formation, the coating layer is bonded to the other surface of the support sheet (the surface of the support sheet on which the film for protective film formation is not provided).

Alternatively, a composite sheet for forming a protective film may be produced by forming a film for forming a protective film on one surface of a support sheet using the composition for forming a protective film; on the other hand, using the coating The cloth composition is formed with a coating layer in advance, and the coating layer is attached to the exposed surface of the support sheet (the surface of the support sheet on which the film for forming a protective film is not provided).

The coating layer and the formation conditions of the film for protective film formation in these cases are the same as the case of the above-mentioned method.

For example, when manufacturing the composite sheet for forming a protective film as shown in FIG. 1, that is, when the composite sheet for forming a protective film is viewed from above, the surface area of the film for forming a protective film is smaller than the surface area of the adhesive layer. In the case of a sheet, in the above-mentioned manufacturing method, a film for forming a protective film cut in advance to a predetermined size and shape may be provided on the adhesive layer.

◎How to use the composite sheet for forming a protective film

The usage method of the composite sheet for protective film formation of this embodiment is as follows, for example.

First, the usage method of the composite sheet for protective film formation when the film for protective film formation is thermosetting is demonstrated.

In this case, first, the back surface of the semiconductor wafer is attached to the film for forming a protective film of the composite sheet for forming a protective film, and the composite sheet for forming a protective film is fixed to a dicing device.

Next, the film for protective film formation is hardened by heating, and it is set as a protective film. A back grinding tape is attached to the surface (electrode formation surface) of the semiconductor wafer In this case, the back grinding tape is usually removed from the semiconductor wafer to form a protective film.

Next, the semiconductor wafer is diced to produce a semiconductor wafer. During the period from the formation of the protective film to the dicing, the protective film may be irradiated with laser light from the coating side of the composite sheet for forming a protective film to print on the surface of the protective film. In this case, as explained above, when the gloss value of the surface (back surface) on the opposite side to the side in contact with the support sheet in the coating layer is within the above-mentioned specific range, the protective film can be clearly irradiated. Shot printing.

In addition, with respect to the semiconductor wafer before dicing or the semiconductor wafer obtained by dicing, an infrared camera or the like may be used from the back surface (surface to which the composite sheet for forming a protective film is attached) of the semiconductor wafer or the semiconductor wafer. An observation is made to detect the state. For example, in the case of a semiconductor wafer, the presence or absence of breakage, such as a chip or a crack, may be detected in the semiconductor wafer.

On the other hand, in the semiconductor wafer with the protective film of the present embodiment, as described above, the gloss value of the surface (back surface) opposite to the side in contact with the support sheet in the coating layer is within the specific range as described above. , and further, the formation of voids between the coating layer and the back surface of the support sheet is suppressed. Therefore, when a semiconductor wafer or a semiconductor wafer is observed with an infrared camera or the like from the coating side through the composite sheet for forming a protective film, a clear inspection image can be obtained, so that the inspection can be performed with high accuracy.

Then, from the support sheet, the semiconductor wafer is peeled off together with the protective film attached to the back surface of the semiconductor wafer and picked up, thereby obtaining a semiconductor wafer with a protective film. For example, when the support sheet is formed by laminating a base material and an adhesive, and the adhesive layer is energy ray curable, the adhesive layer is cured by irradiating the energy ray, and the cured adhesive layer is , pick up the semiconductor wafer together with the protective film attached to the backside of the semiconductor wafer, thereby more easily obtaining the semiconductor wafer with the protective film.

For example, when the composite sheet 1 for forming a protective film shown in FIG. 1 is used, the back surface of the semiconductor wafer is attached to the film 13 for forming a protective film of the composite sheet 1 for forming a protective film, and the exposed support sheet 10 is attached to the back surface of the semiconductor wafer. The (adhesive layer 12 ) is attached to a dicing jig (not shown) such as an annular frame, and the composite sheet 1 for forming a protective film is fixed to a dicing device. Next, after curing the protective film-forming film 13 to form a protective film, the protective film is laser-printed and then cut, and the adhesive layer 12 is adhered to the aforementioned treatment by irradiating energy rays as necessary. The area other than the part of the tool is hardened, and then the semiconductor wafer with the protective film can be picked up. In this way, when the composite sheet 1 for forming a protective film having the adhesive layer 12 having energy ray curability is used, it is necessary to prevent the composite sheet 1 for forming a protective film from peeling off the jig and to prevent the specific adhesive layer 12 from being peeled off. Area hardening is adjusted. On the other hand, when using the composite sheet 1 for protective film formation, there is no need to separately provide a structure for attaching the composite sheet 1 for protective film formation to the aforementioned jig.

On the other hand, when the composite sheet 2 for protective film formation shown in FIG. 2 is used, the back surface of the semiconductor wafer is adhered to the film 23 for protective film formation of the composite sheet 2 for protective film formation, and a jig is used for The adhesive layer 16 is attached to a dicing jig (not shown) such as an annular frame, and the composite sheet 2 for forming a protective film is fixed to the dicing device. Next, after hardening the film 23 for protective film formation to make a protective film, the protective film is laser-printed, then diced, and the adhesive layer 12 is cured by irradiating energy rays as necessary, and then the protective film is picked up. The semiconductor chip can be used. In this way, when the composite sheet 2 for forming a protective film having the adhesive layer 12 having energy ray curability is used, unlike the case where the composite sheet 1 for forming a protective film is used, it is not necessary to prevent a specific region of the adhesive layer 12 from being cured. way to adjust. On the other hand, unlike the composite sheet 1 for protective film formation, the composite sheet 2 for protective film formation must be provided with the adhesive agent layer 16 for jigs. By having the adhesive layer 16 for a jig, the adhesive layer 12 can have a wide range of compositions selected according to the purpose.

Next, the usage method of the composite sheet for protective film formation when the film for protective film formation is energy ray curability is demonstrated.

In this case, first, similarly to the case where the film for forming a protective film is thermosetting, the back surface of the semiconductor wafer is adhered to the film for forming a protective film of the composite sheet for forming a protective film, and the composite sheet for forming a protective film is laminated. The sheet is fixed to the cutting device.

Next, the film for protective film formation is hardened by irradiating an energy ray, and a protective film is produced. A backside surface is attached to the surface (electrode formation surface) of the semiconductor wafer. In the case of tape grinding, the back grinding tape is usually removed from the semiconductor wafer to form a protective film.

Next, the semiconductor wafer is diced to produce a semiconductor wafer. During the period from the formation of the protective film to the dicing, the protective film may be irradiated with laser light from the coating side of the composite sheet for forming a protective film to print on the surface of the protective film. The process from this printing to cutting can be carried out in the same manner as in the case where the above-mentioned film for forming a protective film is thermosetting, and similarly to this case, the protective film can be clearly laser-printed, and it is possible to use an infrared camera detection with high accuracy.

Then, from the support sheet, the semiconductor wafer is peeled off together with the protective film attached to the back surface of the semiconductor wafer and picked up, thereby obtaining a semiconductor wafer with a protective film.

This method is particularly preferable when, for example, a support sheet is formed by laminating a base material and an adhesive, and the adhesive layer is a non-energy ray-curable composite sheet as a protective film-forming composite sheet. In addition, the case where the film for forming a protective film is cured by irradiating the energy ray, the semiconductor wafer is diced, and the semiconductor wafer with the protective film is picked up has been described, but the above-mentioned adhesive layer is non-energy ray curing. In the case of nature, the film for protective film formation can be hardened by irradiating an energy ray at any stage before picking up a semiconductor wafer.

For example, when a support sheet is used to laminate a substrate and an adhesive, and In the case where the adhesive layer is an energy ray-curable composite sheet for forming a protective film, the method described below is preferred.

That is, first, similarly to the above-mentioned case, the back surface of the semiconductor wafer is attached to the film for forming a protective film of the composite sheet for forming a protective film, and the composite sheet for forming a protective film is fixed to a dicing device.

Next, the protective film is irradiated with laser light from the coating side of the composite sheet for protective film formation, the surface of the protective film is printed, and the semiconductor wafer is further cut to form a semiconductor wafer. The process from this printing to cutting can be carried out in the same manner as in the case where the above-mentioned film for forming a protective film is thermosetting, and similarly to this case, the protective film can be clearly laser-printed, and it is possible to use an infrared camera detection with high accuracy.

Next, the film for forming a protective film is hardened by irradiating energy rays to form a protective film, and the adhesive layer is hardened, and from the hardened adhesive layer, the semiconductor chip and the back surface attached to the semiconductor chip are protected. The films are picked up together, whereby a semiconductor wafer with a protective film is obtained.

On the other hand, when winding a long composite sheet for protective film formation, it is usually used in a state where a release film (release film 15 in FIGS. 1 and 2 ) is laminated on the exposed surface of the film for protective film formation. The protective film forming composite sheet. Moreover, regardless of the structure of the composite sheet for forming a protective film of the present embodiment (for example, any one of the composite sheet 1 for forming a protective film shown in FIG. 1 and the composite sheet 2 for forming a protective film shown in FIG. 2 ), As the composite sheet for forming a protective film is wound into a roll shape, a coating layer, a support sheet, and a protective film are laminated in this order. All the lamination units of the film for film formation and the release film are sequentially laminated in the radial direction of the roll. As a result, the surface of the release film (the surface on the opposite side to the side on which the film for forming a protective film is provided) of one laminate unit and the surface of the release film of the other laminate unit, which are in contact with each other in the radial direction of the roll, become The back surface of the coating layer (the surface opposite to the side in contact with the base material) is in contact and pressed, and the roller of the composite sheet for forming a protective film is stored in this state as it is. However, by providing the coating layer, the adhesion of these release films and the coating layer between the lamination units can be suppressed, so that the adhesion of the composite sheet for forming a protective film of the present embodiment is suppressed.

Using the composite sheet for forming a protective film provided with a release film on the film for forming a protective film, the peeling force of the release film measured by the following method is preferably 10 mN/50 mm or less, more preferably 7.5 mN/50 mm or less, It is especially preferable that it is 5 mN/50mm or less.

(Measuring method of peeling force of peeling film)

The composite sheet for forming a protective film of this embodiment with a state of having a release film on the film for forming a protective film and having a width of 50 mm and a length of 100 mm, the coating layers are all oriented in the same direction and the total thickness of the coating layers is 10 μm to 60 μm. A plurality of sheets are overlapped to form a laminate in which the first outermost layer is a coating layer and the second outermost layer is a release film, and 980.665mN (that is, 100gf) is applied to the laminate in the lamination direction of the protective film-forming composite sheet. After standing at 40°C for 3 days in the state of ) force (external force), the peeling film closest to the first outermost coating layer in the lamination direction is peeled at a peeling speed of 300mm/min and a peeling angle of 180°. condition, self-adjacency The coating layer (the coating layer closest to the coating layer of the first outermost layer in the above-mentioned lamination direction) was peeled off, and the peeling force at this time was measured. In addition, here, the composite sheet for protective film formation which laminated|stacked a plurality of sheets all has the same structure. Moreover, it is preferable that the number of sheets of the composite sheet for protective film formation to overlap is 10 sheets. From the peeling force of such a peeling film, the level of the blocking-suppressing effect (blocking resistance) of the composite sheet for protective film formation of this embodiment can be confirmed.

[Example]

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited at all by the examples shown below.

<Manufacture of the composite sheet for protective film formation>

[Example 1]

The composite sheet for protective film formation of the structure shown in FIG. 1 was manufactured. A plan view of the composite sheet for forming a protective film is shown in FIG. 3 . More specifically, it is as follows.

[Manufacture of the first laminate]

(Preparation of composition for forming thermosetting protective film)

The following components were prepared in the following amounts (solid content), and methyl ethyl ketone was further prepared to obtain a composition (III-1) for forming a protective film having a solid content concentration of 51% by mass.

(polymer component (A))

(A)-1: Acrylic resin obtained by copolymerizing 10 parts by mass of n-butyl acrylate, 70 parts by mass of methyl acrylate, 5 parts by mass of glycidyl methacrylate, and 15 parts by mass of 2-hydroxyethyl acrylate (weight average molecular weight 400,000, glass transition temperature -1°C) 150 parts by mass.

(Thermosetting component (B))

‧Epoxy resin (B1)

(B1)-1: bisphenol A epoxy resin ("JER828" by Mitsubishi Chemical Corporation, epoxy equivalent 183 g/eq to 194 g/eq, molecular weight 370) 60 parts by mass.

(B1)-2: 10 parts by mass of bisphenol A epoxy resin (“JER1055” manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 800 g/eq to 900 g/eq, molecular weight 1600).

(B1)-3: Dicyclopentadiene-type epoxy resin ("Epiclon HP-7200HH" by DIC Corporation, epoxy equivalent 274g/eq-286g/eq) 30 mass parts.

‧Thermosetting agent (B2)

(B2)-1: Dicyandiamide (solid dispersion type latent hardener, "Adeka Hardener EH-3636AS" manufactured by ADEKA, active hydrogen amount 21 g/eq) 2 parts by mass.

(hardening accelerator (C))

(C)-1: 2 parts by mass of 2-phenyl-4,5-dihydroxymethylimidazole (“Curezol 2PHZ” manufactured by Shikoku Chemical Industry Co., Ltd.).

(filler (D))

(D)-1: Silica filler (Admatechs "SC2050MA", surface-modified with an epoxy compound, average particle size 0.5 μm) 320 parts by mass.

(Coupling Agent (E))

(E)-1: γ-glycidyloxypropyltrimethoxysilane (silane coupling agent, "KBM403" manufactured by Shin-Etsu Chemical Co., Ltd., methoxyl equivalent 12.7 mmol/g, molecular weight 236.3) 0.4 part by mass.

(Colorant (I))

(I)-1: 1.2 parts by mass of carbon black (pigment, "MA600B" manufactured by Mitsubishi Chemical Corporation, average particle size: 28 nm).

(Formation of the film for protective film formation, production of the first laminate)

Using a knife coater, the protective film-forming composition (III-1) obtained above was applied on the peeling-treated surface of the first peeling film (“SP-P502010*” manufactured by Lintec Corporation, thickness 50 μm), It dried at 120 degreeC for 2 minutes, and formed the film for protective film formation (thickness 25 micrometers).

Next, the peeling treatment surface of the second peeling film (“SP-PET381031C” manufactured by Lintec, thickness 38 μm) was bonded to the surface on the opposite side of the surface on which the first peeling film was provided in the film for forming a protective film. , to obtain a long layered body in which the first release film, the film for protective film formation, and the second release film were laminated in this order. Next, after the long layered product is wound into a roll, the layered product is cut into the width direction of the layered product (the width indicated by the symbol w ₁ in the composite sheet 1 for forming a protective film shown in FIG. 3 ). direction) is 300mm in size.

Then, with respect to the cut laminate, from the side of the second peeling film, the second peeling film and the film for protective film formation were drawn together in a circular shape with a diameter of 220 mm in plan view at the center portion in the width direction of the laminate. A half cut of the incision is performed in this way. In addition, the "planar view" of the laminated body in this specification means seeing the laminated body downward from the upper direction of the lamination direction of the laminated body. Then, the second release film and the film for forming a protective film are removed from the above-mentioned laminated body so that only the circular portion formed by the half cut remains, to obtain sequentially on the release-treated surface of the first release film. The 1st laminated body which laminated|stacked the film for protective film formation which are circular in plan view, and a 2nd peeling film. The circular film for forming a protective film in the first laminate corresponds to the film 13 for forming a protective film having a diameter d1 of 220 mm in the composite sheet ₁ for forming a protective film shown in FIG. 3 .

(Preparation of coating composition)

Dispersion liquid (“OSCAL1632” manufactured by Catalytic Chemical Industry Co., Ltd.) in which silica sol is dispersed in 2-ethoxyethanol (ethyl cellosolve), the particle size of silica sol is 30nm to 50nm, solid A hard coat agent (“BEAMSET 575CB” manufactured by Arakawa Chemical Industry Co., Ltd., manufactured by Arakawa Chemical Industry Co., Ltd., solid content concentration 100 % by mass, containing a photopolymerization initiator) 100 parts by mass to obtain a coating composition (solid content concentration: 30 mass %).

(Formation of coating)

Next, using a wire bar coater, the surface roughness Ra on the uneven surface was 0.4 μm, and the surface roughness Ra of the surface opposite to the uneven surface was 0.02 μm. The polypropylene base material (thickness 100 μm) , the aforementioned uneven surface with a melting point of 140°C to 160°C) is coated with the coating composition obtained above, dried at 80°C for 1 minute, and then irradiated with ultraviolet rays at a light intensity of about 230mJ/cm ² to harden the dried coating film , forming a coating (thickness 3 μm).

(Preparation of Adhesive Composition)

100 parts by mass of alkyl (meth)acrylate copolymer and 10 parts by mass (solid content) of an aromatic polyisocyanate compound (crosslinking agent, "Takenate D110N" manufactured by Mitsui Chemicals Co., Ltd.) were prepared, and a methyl group was further prepared. Ethyl ketone was used to obtain an adhesive composition (iii) having a solid content concentration of 30% by mass.

The above-mentioned alkyl (meth)acrylate copolymer is obtained by copolymerizing 40 parts by mass of n-butyl acrylate, 55 parts by mass of 2-ethylhexyl acrylate, and 5 parts by mass of 2-hydroxyethyl acrylate and having a weight average molecular weight of 600,000 of acrylic resin.

(Formation of the adhesive layer (support sheet), production of the second laminate)

Using a knife coater, peeling treatment was performed by forming a polysiloxane-based release agent layer on one side, and the third release film (manufactured by Lintec Co., Ltd.) was made of polyethylene terephthalate with a thickness of 38 μm. "SP-PET381031C") was coated with the adhesive composition (iii) obtained above and dried to form an adhesive layer (thickness 5 μm).

Then, after corona treatment is performed on the surface of the substrate on which the coating layer is formed on the opposite side to the uneven surface, the adhesive layer is bonded to the corona treated surface to obtain a coating layer, a substrate, and an adhesive. A layer and a 3rd peeling film are laminated|stacked in this order, and the elongate 2nd laminated body containing a support sheet is included.

Next, after winding this long 2nd laminated body into a roll, this 2nd laminated body is cut|disconnected so that the width direction of this 2nd laminated body (in the composite sheet 1 for protective film formation shown in FIG. The direction _of the width represented by w1) is 300mm in size.

(Manufacture of a composite sheet for forming a protective film)

The 2nd peeling film was removed from the 1st laminated body obtained above, and the film for protective film formation of a circular shape was exposed. Moreover, the 3rd peeling film was removed from the 2nd laminated body obtained above, and the adhesive layer was exposed. Then, by bonding the exposed surface of the film for forming a protective film to the exposed surface of the adhesive layer, a coating layer, a base material, an adhesive layer, a film for forming a protective film, and a first release film are obtained in this order. The third laminate of the laminated protective film-forming composite sheet.

For the third layered product obtained above, from the coating side, half-cutting was performed to cut out the entire coating layer, the base material and the adhesive layer so as to draw a circle with a diameter of 270 mm in plan view. In this half-cut, the above-mentioned circle with a diameter of 270 mm in plan view was concentric with the circle with a diameter of 220 mm formed by the film for forming a protective film, and the entire coating layer, base material and adhesive layer were cut out.

Then, with respect to the circle having a diameter of 270 mm, in a plan view, at a position 20 mm away from the radially outer side of the circle, the width direction of the third laminate (the composite sheet for forming a protective film shown in FIG. 3 ) is drawn. In 1, the width direction indicated by the symbol w ₁ ) is opposite to a pair of circular arcs, from the coating side, the coating, the substrate and the adhesive layer are all cut out and half-cut.

The notches corresponding to the pair of arcs form the curved peripheral edge portion of the adhesive layer indicated by reference numeral 121 in the composite sheet 1 for forming a protective film shown in FIG. 3 . In addition, the distance (20 mm) between the circle with a diameter of 270 mm and the aforementioned circular arc corresponds to the symbol w ₂ in the composite sheet 1 for forming a protective film shown in FIG. 3 .

This kind of drawing 2 is performed at a plurality of locations in the longitudinal direction of the third laminate (the direction orthogonal to the width direction indicated by the symbol w ₁ in the composite sheet 1 for forming a protective film shown in FIG. 3 ). The above-mentioned half-cuts of two concentric circles and a pair of circular arcs are used to draw two straight lines connecting the circular arcs in the aforementioned longitudinal direction between adjacent parts in plan view. The entire material and the adhesive layer are half-cut to cut out the incision. The notches corresponding to the two straight lines form the planar peripheral edge portion 122 of the adhesive layer indicated by the reference numeral 122 in the composite sheet 1 for forming a protective film shown in FIG. 3 .

Then, the coating layer, the base material and the adhesive layer in the part between the above-mentioned circle with a diameter of 270 mm and a pair of arcs, and the part sandwiched by the two straight lines connecting the above-mentioned arcs to each other in plan view were moved. Thereby, the composite sheet for protective film formation shown in FIG. 1 and FIG. 3 was obtained. The circular adhesive layer (support sheet) in the composite sheet for forming a protective film corresponds to the circular adhesive layer 12 (support sheet 10 ) having a diameter d ₂ of 270 mm in FIG. 3 . In addition, the 1st release film in this composite sheet for protective film formation corresponds to the release film 15 in FIG. 3 .

[Example 2]

As shown in Table 1, a composite sheet for forming a protective film was obtained by the same method as in Example 1, except that the surface roughness Ra of the uneven surface was 1 μm instead of 0.4 μm.

[Example 3]

As shown in Table 1, the same method as in Example 1 was used except that the surface roughness Ra of the uneven surface was 1 μm instead of 0.4 μm, and the thickness of the coating layer was 1 μm instead of 3 μm. A composite sheet for forming a protective film was obtained.

[Example 4]

As shown in Table 1, except that the thickness of the coating layer was 1 μm instead of 3 μm, the same method as in Example 1 was used to obtain a composite sheet for forming a protective film.

[Example 5]

As shown in Table 1, the base material with the surface roughness Ra of the concave-convex surface was 1 μm instead of 0.4 μm, and the thickness of the coating layer was 6 μm instead A composite sheet for forming a protective film was obtained by the same method as in Example 1 except for this point of 3 μm.

[Example 6]

As shown in Table 1, the same method as in Example 1 was used except that the surface roughness Ra of the uneven surface was 3 μm instead of 0.4 μm, and the thickness of the coating layer was 6 μm instead of 3 μm. A composite sheet for forming a protective film was obtained.

[Comparative Example 1]

As shown in Table 1, except that the surface roughness Ra of the concavo-convex surface was 1 μm instead of 0.4 μm, and the coating layer was not formed, the same method as in Example 1 was used to obtain a composite for forming a protective film. piece.

[Comparative Example 2]

As shown in Table 1, the base material is arranged so that the uneven surface faces the opposite side, that is, the adhesive layer side (inner side), and the coating layer is not formed (that is, the conventional structure shown in FIG. 5 is used), except Except this point, by the same method as Example 1, the composite sheet for protective film formation was obtained.

[Comparative Example 3]

As shown in Table 1, a base material having a surface roughness Ra of 1 μm, not 0.4 μm, of the uneven surface was used, and the base material was arranged so that the uneven surface faced the opposite side, that is, the adhesive layer side (inner side), and did not form coating (that is, It is the conventional structure shown in FIG. 5), except for this point, by the method similar to Example 1, the composite sheet for protective film formation was obtained.

[Comparative Example 4]

Spherical silica (“SC2050MA” manufactured by Admatechs, average particle size: 0.5 μm) surface-modified with epoxy groups was used in the same amount in terms of solid content, instead of silica sol and dispersed in 2-ethoxy A coating composition was prepared by the same method as in Example 1 except for the dispersion liquid prepared in ethanol.

And using this coating composition, except this point, by the method similar to Example 1, the composite sheet for protective film formation was obtained.

In the obtained composite sheet for forming a protective film, as shown in Table 1, the surface roughness Ra of the outermost surface on the substrate side was 0.8 μm.

<Evaluation of the composite sheet for protective film formation>

[Laser printability]

In the composite sheet for forming a protective film of each of the Examples and Comparative Examples obtained above, the first release film was removed, and an adhesive layer was attached using an attaching device (“RAD-2700F/12” manufactured by Lintec Corporation). A film for forming a protective film was attached to the back surface of a silicon wafer (outer diameter 8 inches, thickness 100 μm) heated to 70° C. in a stainless steel ring frame.

Next, the film for protective film formation was heat-processed at 130 degreeC for 2 hours, and the film for protective film formation was thermally hardened, and a protective film was formed.

Then, using a printing device (manufactured by KEYENCE Corporation) "VK9700"), under the conditions of output 0.6W, frequency 40kHz, scanning speed 100mm/sec, irradiate the protective film with laser light with wavelength of 532nm from the substrate side, according to the following two patterns (pattern 1, pattern 2) Laser print on the protective film.

(pattern)

Pattern 1: The character size is 0.4mm×0.5mm, the character interval is 0.3mm, and the number of characters is 20.

Pattern 2: The character size is 0.2mm×0.5mm, the character interval is 0.3mm, and the number of characters is 20.

Next, regarding the characters formed on the protective film by the above-mentioned laser printing, the visibility (laser printing property) from the base material side was evaluated according to the following criteria. The results are shown in Table 1.

(Evaluation Criteria)

A: All the characters of pattern 1 and pattern 2 are clear, and the characters of pattern 1 and pattern 2 can be read without problems.

B: At least a part of the characters in the pattern 2 is not clear, but all the characters in the pattern 1 are clear, and the characters in the pattern 1 can be read without problems.

C: In any of pattern 1 and pattern 2, at least a part of characters are unclear.

[Blocking Resistance (1)]

The above-obtained composite sheets for forming protective films of each of the Examples and Comparative Examples were wound into a 3-inch diameter sheet with a length of 10 m. The core material made of ABS (Acrylonitrile-Butadiene-Styrene; acrylonitrile-butadiene-styrene) resin was left to stand at room temperature for 3 days as it was.

Next, with respect to the composite sheets for forming a protective film of Examples 1 to 5, an attempt was made to roll out 10 lamination units in which the coating layer, the base material, the adhesive layer, the film for forming a protective film, and the first release film were laminated in this order. For the composite sheets for forming a protective film from Comparative Examples 1 to 3, since there is no coating layer, an attempt was made to roll out the composite sheet in which the base material, the adhesive layer, the film for forming a protective film and the first release film were laminated in this order. For 10 lamination units, at this time, it was evaluated whether or not the contact parts of the protective film-forming composite sheets that were in contact with each other during winding were adhered to each other, and when there was adhesion, the degree of adhesion was evaluated according to the following criteria. The results are shown in Table 1.

(Evaluation Criteria)

A: Adhesion of the aforementioned contact portions to each other was not confirmed at all.

B: Slight adhesion of the above-mentioned contact portions was confirmed, but the composite sheet for forming a protective film could be rolled out without any problem.

C: A part of the said contact part adhered completely, and when the composite sheet for protective film formation was rolled out, the 1st peeling film was peeled from an adhesive bond layer.

[Blocking Resistance (2)]

The composite sheet for forming a protective film of each of the Examples and Comparative Examples obtained above was cut out so as to be a tape having a width of 50 mm and a length of 100 mm. In addition, when cutting, the longitudinal direction of this tape was made to correspond to the application direction of the adhesive composition.

Ten pieces of the thus obtained tapes were prepared, and these tapes were laminated to prepare test pieces. At this time, in the case of Examples 1 to 5, the aforementioned tapes were laminated with the coating layer facing upward. In addition, in the case of Comparative Example 1 to Comparative Example 3, since there is no coating layer, the aforementioned tapes are all laminated with the substrate facing upward. Next, this test piece was sandwiched between two glass plates (width 75 mm, length 15 mm, thickness 5 mm), and the entire laminate of these glass plates and test pieces was placed on a predetermined position with one glass plate as the lowermost layer, and placed on the other. A plumb weight was placed on the uppermost glass plate to pressurize the test piece. At this time, the force applied to the test piece in the lamination direction of the tape was 980.665 mN (ie, 100 gf). In this state, the entire laminate of these glass plates and test pieces was stored in a moist heat accelerator (manufactured by ESPEC) at 40° C. for 3 days, and the above-mentioned test pieces were subjected to a heat and pressure acceleration test.

Then, the test piece was taken out from the moist heat accelerator, and the first release film of the lowermost layer (the first release film of the lowermost layer in contact with the glass plate) and the film for forming a protective film adjacent to the first release film were removed. , the exposed adhesive layer is attached to the support plate through the double-sided adhesive tape, thereby removing only the first release film of the lowermost layer and the first release film adjacent to the first release film from the test piece after the heating and pressure acceleration test. The test piece obtained by the film for protective film formation was fixed to the said support plate.

Then, in the case of Example 1 to Example 5, the above-mentioned fixed material, the uppermost layer farthest from the above-mentioned support plate, is composed of the coating layer, the base material, the adhesive layer and the protective film forming film. Remove, use a tensile tester, peel the exposed first release film from the adjacent coating under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180°, and measure the peeling at this time. force. In the case of Comparative Examples 1 to 3, the laminates consisting of the base material, the adhesive layer and the protective film forming film in the uppermost layer farthest from the above-mentioned support plate were removed from the above-mentioned fixed material, and the layer was removed using a pulling method. A tensile tester was used to peel the exposed first release film from the adjacent substrate under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180°, and the peeling force at this time was measured. The measured value of the peeling force of the first peeling film thus obtained was used as an index of the blocking resistance of the composite sheet for forming a protective film.

Furthermore, when the peeling force of the first peeling film to be measured is sufficiently small, the test piece is taken out from the moist heat accelerator, and the first peeling film (most When the protective film forming film adjacent to the first release film in contact with the glass plate of the lower layer is removed, the first release film that is the measurement object of the release force is first removed from the layer adjacent to the first release film (in Example 1). In the case of 1 to Example 5, it is a coating layer, and in the case of Comparative Example 1 to Comparative Example 3, it is a case of peeling off. In this case, the test piece is taken out from the moist heat accelerator, and after the first release film of the lowermost layer is removed from the test piece, the protective film forming film adjacent to the first release film is not removed, and the protective film is not removed. The film for forming is attached to the support plate via a double-sided adhesive tape, whereby the test piece obtained by removing only the first release film of the lowermost layer from the test piece is fixed to the support plate, and the same as above for the fixing object The peeling force of the first peeling film was measured.

The results are shown in Table 1.

[Surface roughness Ra of the outermost surface on the substrate side]

For the protective film-forming composite sheets of the respective Examples and Comparative Examples obtained above, using a contact surface roughness meter (“SURFTEST SV-3000” manufactured by Mitutoyo Corporation), the critical value λ c was set to 0.8 mm, and the The evaluation length Ln was set to 4 mm, and the outermost surface on the base material side, that is, the surface roughness Ra of the surface opposite to the base material side in the coating layer was measured according to JIS B0601:2001. The results are shown in Table 1. In Table 1, for the composite sheets for forming a protective film of Comparative Examples 1 to 3, the surface roughness Ra of the surface opposite to the adhesive layer side of the above-mentioned base material is described as the surface roughness of the outermost surface on the base material side Ra.

[Gloss value of the coated surface]

The composite sheet for forming a protective film of each of the above-obtained Examples and Comparative Examples was obtained from a glossmeter (Glossmeter "VG 2000" manufactured by Nippon Denshoku Co., Ltd.) in accordance with JIS K 7105. On the other side, the 20° specular gloss of the surface of the coating layer was measured, and the measured value was set as the gloss value of the surface of the coating layer. The results are shown in Table 1.

[Measured value of haze from coating side]

The haze was measured from the coating side in accordance with JIS K 7136 using a haze meter (“NDH-2000” manufactured by Nippon Denshoku Kogyo Co., Ltd.) for the protective film-forming composite sheets of the respective Examples and Comparative Examples obtained above. . The results are shown in Table 1.

[Table 1]

The composite sheets for forming protective films of Examples 1 to 6 are provided with a coating on the outermost layer on the substrate side, and the gloss value of the surface of the coating is within a specific range, and the laser printing properties and blocking resistance are improved. All are good.

In particular, the composite sheets for forming a protective film of Example 1, Example 2, Example 4, and Example 5 were excellent in laser printability compared to the composite sheets for forming a protective film of Examples 3 and 6 , the reason is presumed that in the composite sheets for forming a protective film of Example 1, Example 2, Example 4 and Example 5, the gloss value of the surface of the coating layer was slightly larger, which was within a more suitable range.

In addition, the composite sheets for forming protective films of Examples 1 to 4 were Compared with the composite sheets for forming a protective film of Examples 5 and 6, the blocking resistance is superior, and the reason is presumed that the thickness of the coating layer of the composite sheets for forming a protective film of Examples 1 to 4 is thinner. .

In addition, regarding the composite sheet for protective film formation of Example 1 to Example 6, the void part was not confirmed between the base material and the adhesive bond layer.

On the other hand, the composite sheet for forming a protective film of Comparative Example 1 is the same as the composite sheet for forming a protective film shown in FIG. 4 , and the surface (surface) on the side provided with the adhesive layer in the base material is the surface on the opposite side The (back surface) is a concave-convex surface and does not have a coating layer, so although it is excellent in blocking resistance, it is poor in laser printability.

The composite sheet for forming a protective film of Comparative Example 2 is similar to the composite sheet for forming a protective film shown in FIG. 5 , and the surface (back surface) on the opposite side to the surface (surface) on the side provided with the adhesive layer in the base material is: It has a smooth surface and does not have a coating, so although the laser printing is good, the blocking resistance is poor. The composite sheet for forming a protective film of Comparative Example 3 also had the same structure as the composite sheet for forming a protective film of Comparative Example 2, but not only poor blocking resistance but also poor laser printability. The reason is presumed that the surface (surface) on the side with the adhesive layer in the base material is an uneven surface, and the surface roughness Ra of the uneven surface is larger than the surface roughness Ra of the composite sheet for forming a protective film of Comparative Example 2. It is presumed that in Comparative Example 3, since the surface roughness Ra of the uneven surface is large, the shape of the uneven surface is also reflected on the surface of the protective film, and the degree of unevenness on the surface of the protective film is larger than that of Comparative Example 2, thereby diffuse reflection of light Larger and less laser printable. It is further presumed that the composite sheet for forming a protective film of Comparative Example 2 and Comparative Example 3 There are voids between the uneven surface of the base material and the adhesive layer in all cases, but since the surface roughness Ra of the uneven surface of Comparative Example 3 is larger than that of Comparative Example 2, the voids become larger, so Comparative Example 3 phase Compared with Comparative Example 2, the diffuse reflection of light is larger, and the laser printing property is worse.

The composite sheet for forming a protective film of Comparative Example 4 is the same as the composite sheet for forming a protective film of Example 1, and the surface (back surface) on the opposite side to the surface (surface) on the side provided with the adhesive layer in the base material is uneven. Surface, and also has a coating, excellent blocking resistance, but poor laser printing. The reason is presumably that in the composite sheet for forming a protective film of Comparative Example 4, the gloss value of the surface of the coating layer was small and not within a suitable range.

(Industrial Availability)

The present invention can be used to manufacture semiconductor wafers and the like whose back surfaces are protected by a protective film.

1‧‧‧Composite sheet for forming protective film

10‧‧‧Support Sheet

10a‧‧‧Surface of support sheet

10b‧‧‧Back side of support sheet

11‧‧‧Substrate

11a‧‧‧Substrate surface

11b‧‧‧Backside of substrate

12‧‧‧Adhesive layer

12a‧‧‧The surface of the adhesive layer

13‧‧‧Film for forming protective film

13a‧‧‧The surface of the film for forming a protective film

14‧‧‧Coating

14a‧‧‧Coated surface

14b‧‧‧Coated backside

15‧‧‧Peeling film

15a‧‧‧Surface of release film

Claims (5)

A composite sheet for forming a protective film is provided with a film for forming a protective film on a surface of the support sheet, and a coating is provided on the surface of the opposite side with the side having the film for forming the aforementioned protective film in the aforementioned support sheet; The above-mentioned support sheet is formed by laminating a base material and an adhesive; the above-mentioned composite sheet for forming a protective film is formed by laminating the above-mentioned coating layer, a base material, an adhesive layer and a film for forming a protective film in sequence; the above-mentioned base material is provided with The surface of the adhesive layer is a smooth surface, and the surface roughness Ra is 0.001 μm to 0.1 μm; the gloss value of the surface on the opposite side in contact with the support sheet in the coating layer is 32 to 95. The composite sheet for forming a protective film according to claim 1, wherein the composite sheet for forming a protective film further comprising a peeling film on the film for forming a protective film is used, and the peeling force of the peeling film measured by the following method is: 10mN/50mm or less; the method for measuring the peeling force of the aforementioned peeling film is as follows: the aforementioned composite sheet for forming a protective film with a peeling film having a width of 50 mm and a length of 100 mm is provided with a peeling film on the film for forming a protective film, with the aforementioned coating layers all oriented in the same direction and A plurality of sheets are stacked so that the total thickness of the coating layers is 10 μm to 60 μm, thereby forming a layered product in which the first outermost layer is a coating layer and the second outermost layer is a release film, and the layered body is used for forming the protective film. After the composite sheet was left to stand at 40°C for 3 days with a force of 980.665 mN applied in the lamination direction, the coating layer in the lamination direction from the first outermost layer was removed. The latest peeling film was peeled off from the adjacent coating layer under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180°, and the peeling force at that time was measured. The composite sheet for forming a protective film according to claim 1, wherein the value of [the thickness of the coating layer (μm)]/[the surface roughness Ra (μm) of the surface on the side having the coating layer in the support sheet] is 0.5 to 10. The composite sheet for forming a protective film according to claim 1, wherein the adhesive layer is an energy ray curable or non-energy ray curable layer. The composite sheet for forming a protective film according to any one of claims 1 to 4, wherein the film for forming a protective film is a thermosetting or energy ray-curable film.

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