CN108352365B - Protective film forming sheet - Google Patents

Abstract

The present invention relates to a protective film-forming sheet (1) in which a thermosetting resin layer (12) is laminated on a first supporting sheet (101), wherein the thermosetting resin layer (12) is a layer that is to be attached to a surface having bumps of a semiconductor wafer and that forms a first protective film on the surface by thermosetting, and the difference between the surface free energy of the surface of the first supporting sheet (101) side of the thermosetting resin layer (12) before thermosetting and the surface free energy of the surface of the thermosetting resin layer (12) side of the first supporting sheet (101) is 10mJ/m²The above.

Description

Protective film forming sheet

Technical Field

The present invention relates to a protective film-forming sheet.

The present application claims priority based on Japanese application No. 2015-217115 filed in Japan on 11/4/2015, and the contents thereof are incorporated herein.

Background

Conventionally, when a multi-pin LSI package used for an MPU, a gate array, or the like is mounted on a printed circuit board, a flip-chip mounting method is employed as follows: as the semiconductor chip, a semiconductor chip is used in which bump electrodes (bumps) made of eutectic solder, high-temperature solder, gold, or the like are formed on the connection pad portions, and these bumps are brought into face-to-face contact with corresponding terminal portions on the chip mounting board by a so-called flip chip method, and fusion/diffusion bonding is performed.

The semiconductor chip used in such a mounting method can be obtained by, for example, grinding a surface of a semiconductor wafer having bumps formed on a circuit surface, the surface being opposite to the circuit surface, or dicing the semiconductor wafer to obtain individual pieces. In such a process of obtaining a semiconductor chip, in general, in order to protect the circuit surface and the bumps of the semiconductor wafer, a curable resin film laminated on a support sheet is bonded to the bump formation surface, and the film is cured, thereby forming a protective film on the bump formation surface.

As such a curable resin film, a resin film containing a thermosetting component that is cured by heating has been widely used, and as a protective film forming sheet provided with such a thermosetting resin layer, a sheet in which a thermoplastic resin layer having a specific high-temperature elastic modulus is laminated on the film and a thermoplastic resin layer that is non-plastic at 25 ℃ is further laminated on the uppermost layer on the thermoplastic resin layer has been disclosed (for example, see patent document 1). According to patent document 1, the protective film of the protective film forming sheet is excellent in bump filling property, wafer processability, electrical connection reliability after resin sealing, and the like.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2005-028734

Disclosure of Invention

Problems to be solved by the invention

However, when an attempt is made to form a protective film on a bump forming surface by using a conventional protective film forming sheet in which a thermosetting resin layer is laminated on a support sheet, peeling defects such as peeling at the interface between the support sheet and the thermosetting resin layer at the time of peeling the support sheet, and adhesion of an adhesive to the protective film side, or the like, often occur at the interface between the support sheet such as a substrate and an adhesive layer if forced peeling is desired.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a protective film-forming sheet having excellent easy-peeling properties at the interface between a support sheet and a thermosetting resin layer.

Means for solving the problems

The present invention provides a protective film-forming sheet comprising a 1 st support sheet and a thermosetting resin layer laminated thereon, wherein the thermosetting resin layer is a layer which is to be bonded to a surface of a semiconductor wafer having bumps and which is to be thermally cured to form a protective film on the surface, and the difference between the surface free energy of the thermosetting resin layer on the surface of the 1 st support sheet before thermal curing and the surface free energy of the thermosetting resin layer on the surface of the 1 st support sheet is 10mJ/m²The above.

The difference between the contact angle of the 1 st support sheet-side surface of the thermosetting resin layer of the protective film-forming sheet with respect to water before heat curing and the contact angle of the 1 st support sheet-side surface of the thermosetting resin layer with respect to water is preferably 30 ° or more.

ADVANTAGEOUS EFFECTS OF INVENTION

The protective film-forming sheet of the present invention has excellent easy-peeling properties at the interface between the 1 st support sheet and the thermosetting resin layer.

Drawings

FIG. 1 is a sectional view schematically showing one embodiment of a protective film-forming sheet of the present invention.

FIG. 2 is a cross-sectional view schematically showing another embodiment of the protective film-forming sheet of the present invention.

FIG. 3 is a sectional view schematically showing another embodiment of the protective film-forming sheet of the present invention.

FIG. 4 is a cross-sectional view schematically showing an example of a semiconductor wafer having bumps.

FIG. 5 is a sectional view schematically showing a case where the protective film forming sheet of the present invention is stuck to the surface of a semiconductor wafer having bumps.

FIG. 6 is a cross-sectional view schematically showing an example of a semiconductor wafer provided with a protective film formed using the protective film-forming sheet of the present invention.

Description of the symbols

1. 2, 3. protective film-forming sheet

11. 1. th substrate

11 a. side surface of the thermosetting resin layer of the 1 st substrate

12. curable resin layer

12' 1 st protective film

13. 1 st adhesive layer

13 a. surface of adhesive layer No. 1

14. intermediate layer 1

101. 102, 103. the 1 st support sheet

101a, 102a, 103a · 1 st support sheet surface

90 DEG semiconductor wafer

90a · circuit side of a semiconductor wafer

91. bump

91 a. bump surface

911. apex of bump

Detailed Description

The present invention relates to a protective film-forming sheet obtained by laminating a thermosetting resin layer on a 1 st support sheet, wherein the thermosetting resin layer is a layer which is to be attached to a surface having bumps of a semiconductor wafer and which is to be thermally cured to form a protective film on the surface, and the difference between the surface free energy of the surface of the 1 st support sheet side of the thermosetting resin layer before thermal curing and the surface free energy of the surface of the 1 st support sheet side of the thermosetting resin layer is 10mJ/m²The above.

Surface free energy of each solid gamma_s ^totalThis can be determined by: surface free energy gamma for dispersive force component_L ^dSurface free energy of polar component gamma_L ^pAnd surface free energy gamma of hydrogen bond component_L ^hMeasuring the contact angle between the solid surface and each liquid, and calculating the surface free energy gamma of the dispersion force component for the following formula (2)_s ^dSurface free energy of polar component gamma_s ^pAnd surface free energy gamma of hydrogen bond component_s ^hThe related connecting equation is substituted into the following formula (1).

γ_s ^total＝γ_s ^d+γ_s ^p+γ_s ^h···(1)

γ_L(1+cosθ)＝2·(γ_s ^d·γ_L ^d)^1/2+2·(γ_s ^p·γ_L ^p)^1/2+2·(γ_s ^h·γ_L ^h)^1/2···(2)

The protective film forming sheet of the present invention is used by being bonded to the surface of the semiconductor wafer having the bumps through the thermosetting resin layer. Therefore, the thermosetting resin layer after the bonding is heated to increase the fluidity, spreads between the bumps to cover the bumps, adheres to the circuit surface, and covers the surfaces of the bumps, particularly the surfaces of the portions near the circuit surface to embed the bumps. The thermosetting resin layer in this state is further heated to be thermally cured, and finally a 1 st protective film is formed to protect the bump in a state of being in close contact with the surface of the circuit board.

For example, a semiconductor wafer to which a protective film forming sheet is attached is assembled in a state in which a 1 st supporting sheet is removed after grinding a surface opposite to the circuit surface, then a thermosetting resin layer is heated to embed a bump and form a 1 st protective film, and finally the semiconductor device is provided with the 1 st protective film.

In the protective film-forming sheet of the present invention, the difference between the surface free energy of the surface of the first support sheet side of the thermosetting resin layer before thermosetting and the surface free energy of the surface of the first support sheet side of the thermosetting resin layer is 10mJ/m²As described above, no component transfer occurs at the interface between the first support sheet and the second support sheet, and the easy-peeling property at the interface between the first support sheet 1 and the thermosetting resin layer is excellent when the first support sheet 1 is removed. The difference between the surface free energy of the thermosetting resin layer before thermosetting on the surface of the first support sheet 1 and the surface free energy of the thermosetting resin layer on the surface of the first support sheet 1 is preferably 12 to 100mJ/m²More preferably 15 to 90mJ/m²More preferably 18 to 85mJ/m²Particularly preferably 20 to 80mJ/m²。

Further, by setting the difference between the contact angle of the surface of the first support sheet of the thermosetting resin layer with water before thermosetting and the contact angle of the surface of the first support sheet of the thermosetting resin layer with water to 30 ° or more, the easy peelability of the interface between the first support sheet 1 and the thermosetting resin layer at the time of removing the first support sheet can be further improved.

In the protective film-forming sheet of the present invention, the surface on the thermosetting resin layer side of the 1 st supporting sheet is formed of an energy ray-curable adhesive or a non-energy ray-curable adhesive, and when the protective film is formed of an energy ray-curable adhesive, the difference between the surface free energies before the energy ray curing is set to the above range, so that the component transfer does not occur at the interface between the first supporting sheet and the second supporting sheet before the energy ray curing, and the easy peelability at the interface between the 1 st supporting sheet and the thermosetting resin layer can be made excellent even when the 1 st supporting sheet is removed after the energy ray curing. Even if the value of the difference in surface free energy after the energy ray curing deviates from the above range, the influence on the component transfer at the interface between the two before the energy ray curing is small, and the influence on the easy peelability of the interface between the 1 st support sheet and the thermosetting resin layer when the 1 st support sheet is removed is small.

The protective film forming sheet of the present invention will be described in detail below with reference to the drawings.

In the drawings used in the following description, for the sake of easy understanding of the features, the drawings may be different from the actual protective film forming sheet for convenience. The materials, conditions, and the like described in the following description are examples, and the present invention is not limited to these examples, and can be implemented by appropriately changing the materials, conditions, and the like within a range not changing the gist of the present invention.

Supporting sheet 1-

The 1 st support sheet may be composed of 1 layer (single layer) or a plurality of layers of 2 or more. When the support sheet is formed of a plurality of layers, the constituent materials and thicknesses of 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 as long as the effects of the present invention are not impaired.

In the present specification, the phrase "the plurality of layers may be the same or different from each other" is not limited to the case of the 1 st support sheet, and means "all the layers may be the same or different from each other, or only some of the layers may be the same". Further, "the plurality of layers are different from each other" means "at least one of the constituent material and the thickness of each layer is different from each other".

Preferred examples of the 1 st support sheet include: a sheet obtained by laminating a 1 st adhesive layer on a 1 st base material; a sheet in which a 1 st intermediate layer is laminated on a 1 st substrate and a 1 st pressure-sensitive adhesive layer is laminated on the 1 st intermediate layer; a sheet composed of only the 1 st base material, and the like.

Hereinafter, an example of the protective film forming sheet of the present invention will be described with reference to the drawings according to the type of the 1 st supporting sheet.

Fig. 1 is a sectional view schematically showing one embodiment of a protective film forming sheet of the present invention. The protective film-forming sheet 1 shown here uses a sheet in which the 1 st pressure-sensitive adhesive layer 13 is laminated on the 1 st base material as the 1 st supporting sheet 101. That is, the protective film-forming sheet 1 is configured to include the 1 st pressure-sensitive adhesive layer 13 on the 1 st substrate 11 and the thermosetting resin layer 12 on the 1 st pressure-sensitive adhesive layer 13. The 1 st support sheet 101 is a laminate of the 1 st base material 11 and the 1 st adhesive layer 13, and the thermosetting resin layer 12 is provided on one surface 101a of the 1 st support sheet 101, that is, on one surface 13a of the 1 st adhesive layer 13. The protective film-forming sheet 1 was obtained by setting the difference between the surface free energy of the 1 st support sheet 101 side surface of the thermosetting resin layer 12 before thermosetting and the surface free energy of the thermosetting resin layer 12 side surface of the 1 st adhesive layer 13 to 10mJ/m²As described above, component transfer does not occur at the interface between the first support sheet 101 and the thermosetting resin layer 12, the adhesive strength is stable, and the interface between the first support sheet 101 and the thermosetting resin layer 12 is excellent in easy peelability. The difference between the surface free energy of the surface of the first support sheet 101 of the thermosetting resin layer 12 before thermosetting and the surface free energy of the surface of the thermosetting resin layer 12 of the first adhesive layer 13 is preferably 12 to 100mJ/m²More preferably 15 to 90mJ/m²More preferably 18 to 85mJ/m²Particularly preferably 20 to 80mJ/m²。

Fig. 2 is a cross-sectional view schematically showing another embodiment of the protective film forming sheet of the present invention. In fig. 2, the same components as those shown in fig. 1 are denoted by the same reference numerals as those in fig. 1, and detailed description thereof is omitted, and the same applies to fig. 3 and subsequent drawings.

In the protective film-forming sheet 2 shown here, a sheet in which the 1 st intermediate layer 14 is laminated on the 1 st base material 11 and the 1 st pressure-sensitive adhesive layer 13 is laminated on the 1 st intermediate layer 14 is used as the 1 st supporting sheet 102. Specifically, the protective film-forming sheet 2 is configured to include the 1 st intermediate layer 14 on the 1 st substrate 11, the 1 st adhesive layer 13 on the 1 st intermediate layer 14, and the curable resin layer 12 on the 1 st adhesive layer 13. The 1 st support sheet 102 is a laminate in which the 1 st base material 11, the 1 st intermediate layer 14, and the 1 st adhesive layer 13 are laminated in this order, and the thermosetting resin layer 12 is provided on one surface 102a of the 1 st support sheet 102, that is, on one surface 13a of the 1 st adhesive layer 13.

In other words, the protective film-forming sheet 2 is obtained by further providing the 1 st intermediate layer 14 at the interface between the 1 st substrate 11 and the 1 st pressure-sensitive adhesive layer 13 in the protective film-forming sheet 1 shown in fig. 1.

The protective film-forming sheet 2 was obtained by setting the difference between the surface free energy of the 1 st support sheet 102 side surface of the thermosetting resin layer 12 before thermosetting and the surface free energy of the thermosetting resin layer 12 side surface of the 1 st adhesive layer 13 to 10mJ/m²As described above, component transfer does not occur at the interface between the first support sheet 102 and the thermosetting resin layer 12, the adhesive strength is stable, and the interface between the first support sheet 102 and the thermosetting resin layer 12 is excellent in easy releasability. The difference between the surface free energy of the surface of the 1 st support sheet 102 side of the thermosetting resin layer 12 before thermosetting and the surface free energy of the surface of the 1 st adhesive layer 13 on the thermosetting resin layer 12 side is preferably 12 to 100mJ/m²More preferably 15 to 90mJ/m²More preferably 18 to 85mJ/m²Particularly preferably 20 to 80mJ/m²。

Fig. 3 is a sectional view schematically showing another embodiment of the protective film forming sheet of the present invention.

In the protective film forming sheet 3 shown here, as the 1 st supporting sheet 103, a sheet composed only of the 1 st base material 11 is used. That is, the protective film forming sheet 3 is configured to include the curable resin layer 12 on the 1 st substrate 11. The 1 st support sheet 103 is composed of only the 1 st substrate 11, and a curable resin layer 12 is provided on one surface 103a of the 1 st support sheet 103, that is, on one surface 11a of the 1 st substrate 11 in direct contact therewith.

In other words, the protective filmThe forming sheet 3 is obtained by removing the 1 st pressure-sensitive adhesive layer 13 from the protective film forming sheet 1 shown in fig. 1. The protective film-forming sheet 3 was obtained by setting the difference between the surface free energy of the surface of the 1 st support sheet 103 side of the thermosetting resin layer 12 before thermosetting and the surface free energy of the surface of the 1 st support sheet 103 side of the thermosetting resin layer 12 to 10mJ/m²As described above, component transfer does not occur at the interface between the first and second support sheets 103 and the thermosetting resin layer 12, and the adhesive strength is stable, and the interface between the first support sheet 103 and the thermosetting resin layer 12 is excellent in easy peelability. The difference between the surface free energy of the surface of the first support sheet 103 of the thermosetting resin layer 12 before thermosetting and the surface free energy of the surface of the first support sheet 103 of the thermosetting resin layer 12 is preferably 12 to 100mJ/m²More preferably 15 to 90mJ/m²More preferably 18 to 85mJ/m²Particularly preferably 20 to 80mJ/m²。

Fig. 4 is a cross-sectional view schematically showing an example of a semiconductor wafer 90 having bumps 91. The circuit surface 90a of the semiconductor wafer 90 shown here is provided with a plurality of bumps 91.

The bump 91 has a shape in which a part of a ball is cut out in a plane, for example, and the plane corresponding to the cut-out exposed portion is in contact with the circuit surface 90a of the semiconductor wafer 90. The shape of the bump is not limited to the shape shown in the figure, and the effect of the present invention (easy peelability of the interface between the first support sheet 1 and the thermosetting resin layer) can be effectively exhibited particularly when the projection surface is a spherical bump including an elliptical shape.

Fig. 5 is a cross-sectional view schematically showing a case where the protective film forming sheet of the present invention is attached to the surface of the semiconductor wafer 90 having the bump 91. The thermosetting resin layer 12 after the bonding is heated to increase its fluidity, spreads between the bumps to cover the bumps, adheres to the circuit surface, and covers the surfaces of the bumps, particularly the surfaces of the portions near the circuit surface to embed the bumps.

By setting the thickness of the thermosetting resin layer 12 to be thinner than the height of the bump 91 and the total thickness of the curable resin layer 12 and the 1 st adhesive layer 13 to be thicker than the height of the bump 91, the entire bump 91 can be covered with the curable resin layer 12 and the 1 st adhesive layer 13.

The semiconductor wafer to which the protective film forming sheet is attached is, for example, ground on the surface opposite to the circuit surface, the 1 st supporting sheet 101 is removed, then the 1 st protective film 12 'is formed by heating the thermosetting resin layer 12, and finally the chip is cut into the size in a state where the 1 st protective film 12' is provided and assembled in the semiconductor device.

Fig. 6 is a cross-sectional view schematically showing an example of a semiconductor wafer 90 provided with a 1 st protective film 12' formed using the protective film forming sheet 1 of the present invention. The 1 st protective film 12' is formed using the thermosetting resin film of the present invention, and covers the circuit surface 90a of the semiconductor wafer 90 and covers the region of the surface 91a of the bump 91 except for the vertex 911 of the bump 91 and the vicinity thereof.

The protective film-forming sheet 1 of the present invention is excellent in the easy-peeling property at the interface between the 1 st supporting sheet 101 and the thermosetting resin layer 12, that is, the easy-peeling property at the interface between the 1 st pressure-sensitive adhesive layer 13 and the thermosetting resin layer 12, and therefore, when the 1 st supporting sheet 101 is peeled off and removed, a peeling failure does not occur, and as shown in fig. 6, the thermosetting resin layer 12 which becomes the 1 st protective film 12' after curing remains, and the circuit surface and the bumps can be protected.

1 st base Material

The 1 st substrate may be composed of one layer (single layer) or may be composed of a plurality of layers of two or more layers. When the substrate is composed of a plurality of layers, the constituent materials and thicknesses of 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 as long as the effect of the present invention is not impaired.

In the present specification, the phrase "a plurality of layers may be the same or different from each other" means "all the layers may be the same or different from each other, or only some of the layers may be the same" without being limited to the substrate. Further, "the plurality of layers are different from each other" means "at least one of the constituent material and the thickness of each layer is different from each other".

The 1 st base material is in the form of a sheet or a film, and examples of the material of the base material include various resins.

Examples of the resin include: polyethylenes such as Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE), and High Density Polyethylene (HDPE); polyolefins other than polyethylene, such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resins; ethylene copolymers (copolymers obtained using ethylene as a monomer) such as ethylene-vinyl acetate copolymers, ethylene- (meth) acrylic acid ester copolymers, and ethylene-norbornene copolymers; vinyl chloride-based resins (resins obtained using vinyl chloride as a monomer) such as polyvinyl chloride and vinyl chloride copolymers; polystyrene; a polycycloolefin; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene 2, 6-naphthalate, and wholly aromatic polyesters having aromatic ring-type groups in all constituent units; copolymers of two or more of the above polyesters; poly (meth) acrylates; a polyurethane; a urethane acrylate; a polyimide; a polyamide; a polycarbonate; a fluororesin; a polyacetal; modified polyphenylene ether; polyphenylene sulfide; polysulfones; polyether ketones, and the like.

Further, examples of the resin include: a mixture of the above polyester and a resin other than the polyester. In the case of the polymer alloy of the above polyester and the resin other than the polyester, it is preferable that the amount of the resin other than the polyester is a smaller amount.

Further, examples of the resin include: a crosslinked resin obtained by crosslinking one or more of the above resins exemplified above; one or two or more kinds of ionomer or other modified resins among the above resins exemplified above are used.

In the present embodiment, "(meth) acrylic acid" is a concept including both "acrylic acid" and "methacrylic acid". Similarly, for example, "(meth) acrylate" is a concept including both "acrylate" and "methacrylate", and "(meth) acryl" is a concept including both "acryl" and "methacryl".

The number of the resins constituting the 1 st base material may be only one, or may be two or more. When two or more kinds of resins constituting the 1 st base material are used, the combination and ratio thereof can be arbitrarily selected.

The 1 st substrate may be only one layer (single layer) or may be a multilayer of two or more layers. When the 1 st substrate is a multilayer, the multilayer may be the same or different from each other, and the combination of the multilayer is not particularly limited.

The thickness of the No. 1 substrate is preferably 5 to 1000 μm, more preferably 10 to 500 μm, further preferably 15 to 300 μm, and particularly preferably 20 to 150 μm.

Here, "thickness of the 1 st substrate" means the thickness of the entire 1 st substrate, and for example, the thickness of the 1 st substrate composed of a plurality of layers means the total thickness of all layers constituting the 1 st substrate.

The 1 st base material is preferably a material having high thickness accuracy, that is, a material in which thickness variation is suppressed without depending on the portion. Among the above-mentioned constituent materials, those having high thickness accuracy and usable for constituting the 1 st base material include, for example: polyethylene, polyolefins other than polyethylene, polyethylene terephthalate, ethylene-vinyl acetate copolymers, and the like.

The 1 st base material may contain known various additives such as a filler, a colorant, an antistatic agent, an antioxidant, an organic lubricant, a catalyst, and a softener (plasticizer), in addition to the main constituent materials such as the above-mentioned resin.

The 1 st substrate may be transparent or opaque, and may be colored or vapor-deposited with other layers depending on the purpose.

When the 1 st adhesive layer or the curable resin layer described later has energy ray curability, the 1 st substrate is preferably a material that transmits energy rays.

The 1 st substrate can be manufactured by a known method. For example, the 1 st base material containing a resin can be produced by molding a resin composition containing the resin.

1 st adhesive layer

The 1 st adhesive layer is a sheet or film and contains an adhesive.

Examples of the binder include: an acrylic resin (an adhesive made of a resin having a (meth) acryloyl group), a urethane resin (an adhesive made of a resin having a urethane bond), a rubber resin (an adhesive made of a resin having a rubber structure), a silicone resin (an adhesive made of a resin having a siloxane bond), an epoxy resin (an adhesive made of a resin having an epoxy group), polyvinyl ether, polycarbonate, or the like, preferably an acrylic resin.

In the present invention, the "adhesive resin" is a concept including both a resin having adhesiveness and a resin having adhesiveness, and includes not only a case where the resin itself has adhesiveness, but also a resin exhibiting adhesiveness by being used in combination with other components such as an additive, a resin exhibiting adhesiveness due to the presence of a trigger (trigger) such as heat or water, and the like.

The 1 st adhesive layer may be only one layer (single layer) or may be a multilayer of two or more layers. In the case where the 1 st adhesive layer is 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 1 st adhesive layer is preferably 1 to 1000. mu.m, more preferably 5 to 500. mu.m, and particularly preferably 10 to 100. mu.m.

Here, "thickness of the 1 st adhesive layer" means the thickness of the entire 1 st adhesive layer, and for example, the thickness of the 1 st adhesive layer composed of a plurality of layers means the total thickness of all the layers constituting the 1 st adhesive layer.

The 1 st adhesive layer may be a layer formed using an energy ray-curable adhesive or a layer formed using a non-energy ray-curable adhesive. The properties of the 1 st adhesive layer formed using an energy ray-curable adhesive before and after curing can be easily adjusted.

In the present invention, the "energy ray" refers to an electromagnetic wave or a charged particle beam having an energy quantum, and examples thereof include ultraviolet rays, electron beams, and the like.

The ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, a black light lamp, an LED, or the like as an ultraviolet ray source. The electron beam may irradiate a ray generated by an electron beam accelerator or the like.

In the present invention, "energy ray-curable property" refers to a property that curing occurs by irradiation with an energy ray, and "non-energy ray-curable property" refers to a property that curing does not occur even if an energy ray is irradiated.

< 1 adhesive composition >)

The 1 st adhesive layer may be formed using a 1 st adhesive composition containing an adhesive. For example, the 1 st adhesive layer can be formed on a target site by applying the 1 st adhesive composition to the surface of the 1 st adhesive layer to be formed and drying it as necessary. A more specific method for forming the 1 st adhesive layer will be described in detail later together with methods for forming other layers. The content ratio of the components that do not vaporize at room temperature in the 1 st adhesive composition is generally the same as the content ratio of the above components in the 1 st adhesive layer. In the present embodiment, "normal temperature" refers to a temperature at which neither cooling nor heating occurs, that is, a normal temperature, and examples thereof include a temperature of 15 to 25 ℃.

The application of the adhesive composition of item 1 may be carried out by a known method, and examples thereof include methods using various coaters such as an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a curtain coater, a die coater, a knife coater, a screen coater, a meyer bar coater, and a kiss coater.

The drying condition of the 1 st adhesive composition is not particularly limited, but when the 1 st adhesive composition contains a solvent described later, it is preferably dried by heating, and in this case, it is preferably dried, for example, at 70 to 130 ℃ for 10 seconds to 5 minutes.

When the 1 st adhesive layer is energy ray-curable, examples of the 1 st adhesive composition containing an energy ray-curable adhesive, that is, the energy ray-curable 1 st adhesive composition, include: a 1 st adhesive composition (I-1) containing a non-energy ray-curable adhesive resin (I-1a) (hereinafter also abbreviated as "adhesive resin (I-1 a)") and an energy ray-curable compound; a 1 st adhesive composition (I-2) containing an energy ray-curable adhesive resin (I-2a) (hereinafter also abbreviated as "adhesive resin (I-2 a)") having an unsaturated group introduced into a side chain of the non-energy ray-curable adhesive resin (I-1 a); and (1) a 1 st adhesive composition (I-3) comprising the adhesive resin (I-2a) and an energy ray-curable low-molecular-weight compound.

< adhesive composition No. 1 (I-1) >

As described above, the adhesive composition (I-1) of the 1 st aspect contains the non-energy ray-curable adhesive resin (I-1a) and the energy ray-curable compound.

[ adhesive resin (I-1a) ]

The adhesive resin (I-1a) is preferably an acrylic resin.

Examples of the acrylic resin include: an acrylic polymer having at least a structural unit derived from an alkyl (meth) acrylate.

The acrylic resin may have only one kind of structural unit, or two or more kinds of structural units, and in the case of two or more kinds of structural units, the combination and ratio of the two or more kinds of structural units may be arbitrarily selected.

Examples of the alkyl (meth) acrylate include alkyl (meth) acrylates in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is preferably linear or branched.

More specifically, examples of the alkyl (meth) acrylate include: methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, 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 (also known as lauryl (meth) acrylate), tridecyl (meth) acrylate, tetradecyl (meth) acrylate (also known as myristyl (meth) acrylate), Pentadecyl (meth) acrylate, hexadecyl (meth) acrylate (also referred to as palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (also referred to as stearyl (meth) acrylate), nonadecyl (meth) acrylate, and eicosyl (meth) acrylate, and the like.

From the viewpoint of improving the adhesive force of the 1 st adhesive layer, the acrylic polymer preferably has a structural unit derived from an alkyl (meth) acrylate having 4 or more carbon atoms in the alkyl group. Therefore, from the viewpoint of further improving the adhesive strength of the 1 st adhesive layer, the number of carbon atoms of the alkyl group is preferably 4 to 12, and more preferably 4 to 8. The alkyl (meth) acrylate having an alkyl group with 4 or more carbon atoms is preferably an alkyl acrylate.

The acrylic polymer preferably further has a structural unit derived from a functional group-containing monomer in addition to a structural unit derived from an alkyl (meth) acrylate.

Examples of the functional group-containing monomer include: a compound in which the functional group can serve as a starting point of crosslinking by reacting with a crosslinking agent described later, or an unsaturated group can be introduced into a side chain of an acrylic polymer by reacting with an unsaturated group in an unsaturated group-containing compound.

Examples of the functional group in the functional group-containing monomer include: hydroxyl, carboxyl, amino, epoxy, and the like.

That is, examples of the functional group-containing monomer include: hydroxyl group-containing monomers, carboxyl group-containing monomers, amino group-containing monomers, epoxy group-containing monomers, and the like.

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

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; ethylenically unsaturated dicarboxylic acids (dicarboxylic acids having an ethylenically unsaturated bond) such as fumaric acid, itaconic acid, maleic acid, and citraconic acid; anhydrides of the above ethylenically unsaturated dicarboxylic acids; and carboxyalkyl (meth) acrylates such as 2-carboxyethyl methacrylate.

The functional group-containing monomer is preferably a hydroxyl group-containing monomer or a carboxyl group-containing monomer, and more preferably a hydroxyl group-containing monomer.

The functional group-containing monomer constituting the acrylic polymer may be one kind or two or more kinds. When two or more functional group-containing monomers constituting the acrylic polymer are used, the combination and ratio of the two or more functional group-containing monomers can be arbitrarily selected.

In the acrylic polymer, the content of the structural unit derived from the functional group-containing monomer is preferably 1 to 35% by mass, more preferably 3 to 32% by mass, and particularly preferably 5 to 30% by mass, based on the total amount of the structural units.

The acrylic polymer may further contain a structural unit derived from another monomer in addition to the structural unit derived from the alkyl (meth) acrylate and the structural unit derived from the functional group-containing monomer.

The other monomer is not particularly limited as long as it is a monomer copolymerizable with, for example, an alkyl (meth) acrylate.

Examples of the other monomers include: styrene, alpha-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide, and the like.

The other monomer constituting the acrylic polymer may be only one kind or two or more kinds. When the number of the other monomers constituting the acrylic polymer is two or more, the combination and ratio thereof can be arbitrarily selected.

The acrylic polymer can be used as the non-energy ray-curable adhesive resin (I-1 a).

On the other hand, as the energy ray-curable adhesive resin (I-2a), a polymer obtained by reacting an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group (energy ray-polymerizable group) with a functional group in the acrylic polymer can be used.

In the present invention, the "energy ray polymerizability" refers to a property of polymerization occurring by irradiation with an energy ray.

The pressure-sensitive adhesive resin (I-1a) contained in the pressure-sensitive adhesive composition (I-1) of the 1 st pressure-sensitive adhesive composition may be one type or two or more types. When the adhesive resin (I-1a) contained in the adhesive composition (I-1) No. 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

In the adhesive composition (I-1) 1, the content of the adhesive resin (I-1a) is preferably 5 to 99% by mass, more preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass, based on the total mass of the adhesive composition (I-1) 1.

[ energy ray-curable Compound ]

Examples of the energy ray-curable compound contained in the adhesive composition (I-1) of item 1 include: a monomer or oligomer having an energy ray-polymerizable unsaturated group and capable of being cured by irradiation with an energy ray.

Examples of the monomer in the energy ray-curable compound include: polyhydric (meth) acrylates such as trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1, 4-butanediol di (meth) acrylate, and 1, 6-hexanediol (meth) acrylate; urethane (meth) acrylate; polyester (meth) acrylates; polyether (meth) acrylates; epoxy (meth) acrylates, and the like.

Examples of the oligomer in the energy ray-curable compound include: oligomers obtained by polymerizing the monomers exemplified above, and the like.

The energy ray-curable compound is preferably a urethane (meth) acrylate or a urethane (meth) acrylate oligomer from the viewpoint of having a large molecular weight and hardly causing a decrease in the storage modulus of the 1 st pressure-sensitive adhesive layer.

The energy ray-curable compound contained in the adhesive composition (I-1) of the 1 st adhesive composition (I-1) may be one kind or two or more kinds. When the number of the energy ray-curable compounds contained in the adhesive composition (I-1) 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

In the adhesive composition (I-1) 1, the content of the energy ray-curable compound is preferably 1 to 95% by mass, more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass, based on the total mass of the adhesive composition (I-1) 1.

[ crosslinking agent ]

When the above-mentioned acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to a structural unit derived from an alkyl (meth) acrylate is used as the adhesive resin (I-1a), the adhesive composition (I-1) preferably further contains a crosslinking agent.

The crosslinking agent is a component that reacts with the functional groups to crosslink the adhesive resins (I-1a) with each other, for example.

Examples of the crosslinking agent include: isocyanate-based crosslinking agents (crosslinking agents having an isocyanate group), such as toluene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates; epoxy crosslinking agents (crosslinking agents having a glycidyl group) such as ethylene glycol glycidyl ether; aziridine crosslinking agents (crosslinking agents having an aziridinyl group), such as hexa [1- (2-methyl) aziridinyl ] triphosphitriazine; metal chelate crosslinking agents (crosslinking agents having a metal chelate structure) such as aluminum chelate; an isocyanurate-based crosslinking agent (a crosslinking agent having an isocyanurate skeleton), and the like.

The crosslinking agent is preferably an isocyanate-based crosslinking agent from the viewpoint of improving cohesive force of the pressure-sensitive adhesive to improve adhesive strength of the 1 st pressure-sensitive adhesive layer, and from the viewpoint of easy acquisition.

The crosslinking agent contained in the adhesive composition (I-1) No. 1 may be only one kind or two or more kinds. When the number of the crosslinking agents contained in the adhesive composition (I-1) 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

The content of the crosslinking agent in the adhesive composition (I-1) 1 is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 20 parts by mass, and particularly preferably 1 to 10 parts by mass, based on 100 parts by mass of the content of the adhesive resin (I-1 a).

[ photopolymerization initiator ]

The adhesive composition (I-1) of item 1 may further contain a photopolymerization initiator. The 1 st adhesive composition (I-1) containing a photopolymerization initiator sufficiently progresses the curing reaction even when irradiated with energy rays of relatively low energy such as ultraviolet rays.

Examples of the photopolymerization initiator include: benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid methyl ester, and benzoin dimethyl ketal; acetophenone compounds such as acetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and 2, 2-dimethoxy-1, 2-diphenylethane-1-one; acylphosphine oxide compounds such as bis (2,4, 6-trimethylbenzoyl) phenylphosphine oxide and 2,4, 6-trimethylbenzoyl diphenylphosphine oxide; sulfur compounds such as benzyl phenyl sulfide and tetramethylthiuram monosulfide; α -ketol compounds such as 1-hydroxycyclohexyl phenyl ketone; azo compounds such as azobisisobutyronitrile; titanocene compounds such as titanocene; thioxanthone compounds such as thioxanthone; a peroxide compound; diketone compounds such as butanedione; benzil, bibenzyl, benzophenone, 2, 4-diethylthioxanthone, 1, 2-diphenylmethane, 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl ] propanone, 2-chloroanthraquinone, and the like.

As the photopolymerization initiator, for example, the following can be used: quinone compounds such as 1-chloroanthraquinone; photosensitizers such as amines, and the like.

The number of photopolymerization initiators contained in the adhesive composition (I-1) No. 1 may be only one, or may be two or more. When two or more photopolymerization initiators are contained in the adhesive composition (I-1) No. 1, the combination and ratio of these photopolymerization initiators can be arbitrarily selected.

In the adhesive composition (I-1) of claim 1, the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass, based on 100 parts by mass of the energy ray-curable compound.

[ other additives ]

The adhesive composition (I-1) of the 1 st aspect may contain other additives not included in any of the above components within a range not to impair the effects of the present invention.

Examples of the other additives include: known additives such as antistatic agents, antioxidants, softeners (plasticizers), fillers (fillers), rust inhibitors, colorants (pigments and dyes), sensitizers, tackifiers, reaction inhibitors, and crosslinking accelerators (catalysts).

The reaction inhibitor is an additive that inhibits the occurrence of an unintended crosslinking reaction in the 1 st adhesive composition (I-1) during storage, for example, by the action of a catalyst mixed into the 1 st adhesive composition (I-1). Examples of the reaction inhibitor include: more specifically, a reaction inhibitor having 2 or more carbonyl groups (-C (═ O) -) in 1 molecule is exemplified.

The adhesive composition (I-1) of the 1 st adhesive composition may contain only one kind of other additive, or may contain two or more kinds of other additives. When two or more other additives are contained in the adhesive composition (I-1) No. 1, the combination and ratio of these additives can be arbitrarily selected.

The content of the other additives in the adhesive composition (I-1) of the 1 st embodiment is not particularly limited, and may be appropriately selected depending on the kind thereof.

[ solvent ]

The adhesive composition (I-1) of item 1 may contain a solvent. The adhesive composition (I-1) of the 1 st aspect contains a solvent, and thus has improved coating suitability for a surface to be coated.

The solvent is preferably an organic solvent, and examples of the organic solvent include: ketones such as methyl ethyl ketone and acetone; esters (carboxylic acid esters) such as ethyl acetate; tetrahydrofuran, di

Ethers such as alkanes; aliphatic hydrocarbons such as cyclohexane and n-hexane; aromatic hydrocarbons such as toluene and xylene; alcohols such as 1-propanol and 2-propanol.

As the solvent, for example, the solvent used in the production of the adhesive resin (I-1a) may be used directly in the adhesive composition (I-1) No. 1 without removing the solvent from the adhesive resin (I-1 a). Alternatively, the solvent may be the same or different from the solvent used in the production of the adhesive resin (I-1a) when the 1 st adhesive composition (I-1) is produced.

The amount of the solvent contained in the adhesive composition (I-1) No. 1 may be only one, or may be two or more. When the number of the solvents contained in the adhesive composition (I-1) 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

The content of the solvent in the adhesive composition (I-1) of the 1 st embodiment is not particularly limited, and may be appropriately adjusted.

< adhesive composition No. 1 (I-2) >

As described above, the adhesive composition (I-2) of the 1 st embodiment contains the energy ray-curable adhesive resin (I-2a) in which an unsaturated group is introduced into the side chain of the non-energy ray-curable adhesive resin (I-1 a).

[ adhesive resin (I-2a) ]

The adhesive resin (I-2a) can be obtained, for example, by reacting an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group with a functional group in the adhesive resin (I-1 a).

The unsaturated group-containing compound is a compound having a group capable of bonding to the adhesive resin (I-1a) by reacting with a functional group in the adhesive resin (I-1a), in addition to the energy ray-polymerizable unsaturated group.

Examples of the energy ray-polymerizable unsaturated group include: (meth) acryloyl, vinyl (ethenyl group), allyl (2-propenyl), and the like, with (meth) acryloyl being preferred.

Examples of the group capable of bonding to the functional group in the adhesive resin (I-1a) include: isocyanate groups and glycidyl groups capable of bonding to hydroxyl groups or amino groups, and hydroxyl groups and amino groups capable of bonding to carboxyl groups or epoxy groups.

Examples of the unsaturated group-containing compound include: (meth) acryloyloxyethyl isocyanate, (meth) acryloyl isocyanate, glycidyl (meth) acrylate, and the like.

The pressure-sensitive adhesive resin (I-2a) contained in the pressure-sensitive adhesive composition (I-2) of the 1 st stage may be only one type or two or more types. When the adhesive resin (I-2a) contained in the adhesive composition (I-2) of the 1 st adhesive composition (I-2) is two or more, the combination and ratio thereof can be arbitrarily selected.

In the adhesive composition (I-2) 1, the content of the adhesive resin (I-2a) is preferably 5 to 99% by mass, more preferably 10 to 95% by mass, and particularly preferably 10 to 90% by mass, based on the total mass of the adhesive composition (I-2) 1.

[ crosslinking agent ]

When the same acrylic polymer having a structural unit derived from a functional group-containing monomer as that in the adhesive resin (I-1a) is used as the adhesive resin (I-2a), the adhesive composition (I-2) No. 1 may further contain a crosslinking agent.

As the above-mentioned crosslinking agent in the 1 st adhesive composition (I-2), the same ones as those in the 1 st adhesive composition (I-1) can be cited.

The crosslinking agent contained in the adhesive composition (I-2) of the 1 st adhesive composition may be only one kind, or two or more kinds. When the crosslinking agent contained in the adhesive composition (I-2) 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

In the adhesive composition (I-2) 1, the content of the crosslinking agent is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 20 parts by mass, and particularly preferably 1 to 10 parts by mass, based on 100 parts by mass of the content of the adhesive resin (I-2 a).

[ photopolymerization initiator ]

The adhesive composition (I-2) of item 1 may further contain a photopolymerization initiator. The 1 st adhesive composition (I-2) containing a photopolymerization initiator sufficiently progresses the curing reaction even when irradiated with energy rays of relatively low energy such as ultraviolet rays.

As the above photopolymerization initiator in the 1 st adhesive composition (I-2), the same ones as those in the 1 st adhesive composition (I-1) can be cited.

The number of photopolymerization initiators contained in the adhesive composition (I-2) of item 1 may be only one, or may be two or more. When two or more photopolymerization initiators are contained in the adhesive composition (I-2) 1, the combination and ratio thereof can be arbitrarily selected.

In the adhesive composition (I-2) of the 1 st embodiment, the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass, based on 100 parts by mass of the adhesive resin (I-2 a).

[ other additives ]

The adhesive composition (I-2) of claim 1 may contain other additives not included in any of the above components within a range not to impair the effects of the present invention.

As the above-mentioned other additives in the 1 st adhesive composition (I-2), for example, the same ones as those in the 1 st adhesive composition (I-1) can be cited.

The number of other additives contained in the adhesive composition (I-2) of the 1 st adhesive composition may be only one, or may be two or more. When two or more other additives are contained in the adhesive composition (I-2) No. 1, the combination and ratio thereof can be arbitrarily selected.

The content of the other additives in the adhesive composition (I-2) of the 1 st embodiment is not particularly limited, and may be appropriately selected depending on the kind thereof.

[ solvent ]

The 1 st adhesive composition (I-2) may contain a solvent for the same purpose as in the 1 st adhesive composition (I-1).

As the above-mentioned solvent in the 1 st adhesive composition (I-2), the same ones as those in the 1 st adhesive composition (I-1) can be cited.

The amount of the solvent contained in the adhesive composition (I-2) of the 1 st embodiment may be only one, or may be two or more. When the number of the solvents contained in the adhesive composition (I-2) 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

The content of the solvent in the adhesive composition (I-2) of the 1 st embodiment is not particularly limited, and may be appropriately adjusted.

< adhesive composition No. 1 (I-3) >

As described above, the adhesive composition (I-3) of the 1 st embodiment contains the adhesive resin (I-2a) and an energy ray-curable low-molecular compound.

In the adhesive composition (I-3) 1, the content of the adhesive resin (I-2a) is preferably 5 to 99% by mass, more preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass, based on the total mass of the adhesive composition (I-3) 1.

[ energy ray-curable Low-molecular-weight Compound ]

Examples of the energy ray-curable low-molecular weight compound contained in the 1 st adhesive composition (I-3) include monomers and oligomers having an energy ray-polymerizable unsaturated group and curable by irradiation with an energy ray, and examples thereof include those similar to the energy ray-curable compound contained in the 1 st adhesive composition (I-1).

The energy ray-curable low-molecular weight compound contained in the adhesive composition (I-3) of item 1 may be only one type, or two or more types. When the number of the energy ray-curable low-molecular weight compounds contained in the adhesive composition (I-3) 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

The content of the energy ray-curable low-molecular compound in the adhesive composition (I-3) 1 is preferably 0.01 to 300 parts by mass, more preferably 0.03 to 200 parts by mass, and particularly preferably 0.05 to 100 parts by mass, based on 100 parts by mass of the adhesive resin (I-2 a).

[ photopolymerization initiator ]

The adhesive composition (I-3) of item 1 may further contain a photopolymerization initiator. The 1 st adhesive composition (I-3) containing a photopolymerization initiator sufficiently progresses the curing reaction even when irradiated with energy rays of relatively low energy such as ultraviolet rays.

As the above photopolymerization initiator in the 1 st adhesive composition (I-3), the same ones as those in the 1 st adhesive composition (I-1) can be cited.

The photopolymerization initiator contained in the adhesive composition (I-3) No. 1 may be only one kind or two or more kinds. When two or more photopolymerization initiators are contained in the adhesive composition (I-3) No. 1, the combination and ratio of these photopolymerization initiators can be arbitrarily selected.

In the adhesive composition (I-3) of claim 1, the photopolymerization initiator is preferably contained in an amount of 0.01 to 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass, based on 100 parts by mass of the total amount of the adhesive resin (I-2a) and the energy ray-curable low-molecular compound.

[ other additives ]

The adhesive composition (I-3) of claim 1 may contain other additives not included in any of the above components within a range not to impair the effects of the present invention.

As the other additives mentioned above, those same as those in the adhesive composition (I-1) No. 1 can be cited.

The number of other additives contained in the adhesive composition (I-3) No. 1 may be only one, or may be two or more. When two or more other additives are contained in the adhesive composition (I-3) No. 1, the combination and ratio thereof can be arbitrarily selected.

The content of the other additives in the adhesive composition (I-3) of item 1 is not particularly limited, and may be appropriately selected depending on the kind thereof.

[ solvent ]

The 1 st adhesive composition (I-3) may contain a solvent for the same purpose as in the 1 st adhesive composition (I-1).

As the above-mentioned solvent in the 1 st adhesive composition (I-3), the same ones as those in the 1 st adhesive composition (I-1) can be cited.

The amount of the solvent contained in the adhesive composition (I-3) of the 1 st embodiment may be only one, or may be two or more. When the number of the solvents contained in the adhesive composition (I-3) No. 1 is two or more, the combination and ratio thereof can be arbitrarily selected.

The content of the solvent in the adhesive composition (I-3) of the 1 st embodiment is not particularly limited, and may be appropriately adjusted.

< adhesive composition 1 except for adhesive compositions (I-1) to (I-3) of 1 >

Although the first adhesive composition (I-1), the first adhesive composition (I-2) and the first adhesive composition (I-3) are mainly described here, the components described as the components contained in the first adhesive composition (1) other than the 3 types of first adhesive compositions (in the present embodiment, referred to as "the first adhesive composition (1) other than the first adhesive composition (I-1) to (I-3)) can be used in the same manner in the general first adhesive composition (1) other than the 3 types of first adhesive compositions.

Examples of the 1 st adhesive composition other than the 1 st adhesive compositions (I-1) to (I-3) include the 1 st adhesive composition which is not energy ray-curable, in addition to the 1 st adhesive composition which is energy ray-curable.

Examples of the non-energy-ray-curable adhesive composition include compositions containing an adhesive resin such as an acrylic resin (a resin having a (meth) acryloyl group), a urethane resin (a resin having a urethane bond), a rubber resin (a resin having a rubber structure), a silicone resin (a resin having a siloxane bond), an epoxy resin (a resin having an epoxy group), a polyvinyl ether, or a polycarbonate, and preferably compositions containing an acrylic resin.

The 1 st adhesive composition other than the 1 st adhesive compositions (I-1) to (I-3) preferably contains one or more kinds of crosslinking agents, and the content thereof may be the same as in the case of the 1 st adhesive composition (I-1) and the like.

< method for producing adhesive composition > 1 >

The 1 st adhesive composition such as the 1 st adhesive compositions (I-1) to (I-3) can be obtained by blending the adhesive and, if necessary, components other than the adhesive, and the like for each component constituting the 1 st adhesive composition.

The order of addition of the components is not particularly limited, and two or more components may be added simultaneously.

When a solvent is used, the solvent may be mixed with any compounding ingredient other than the solvent to dilute the compounding ingredient in advance and then used, or the solvent may be mixed with any compounding ingredient other than the solvent without diluting the compounding ingredient in advance and used.

The method of mixing the components at the time of blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer, a paddle, or the like, a method of mixing using a mixer, and a method of mixing by applying ultrasonic waves.

The temperature and time at the time of addition and mixing of each component are not particularly limited as long as each component is not deteriorated, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ℃.

1 st intermediate layer

The 1 st intermediate layer is in the form of a sheet or a film, and the material of the intermediate layer may be appropriately selected depending on the purpose, and is not particularly limited.

For example, in the case where the shape of bumps existing on the semiconductor surface is reflected by the protective film covering the semiconductor surface, and the deformation of the protective film is suppressed, a preferable constituent material of the 1 st intermediate layer is urethane (meth) acrylate or the like from the viewpoint of further improving the adhesiveness of the 1 st intermediate layer.

The 1 st intermediate layer may be only one layer (single layer) or may be a multilayer of two or more layers. When the 1 st intermediate layer is 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 1 st intermediate layer may be appropriately adjusted depending on the height of the bump on the semiconductor surface to be protected, but is preferably 50 to 600 μm, more preferably 70 to 500 μm, and particularly preferably 80 to 400 μm, from the viewpoint of easily absorbing the influence of a high-height bump.

Here, "thickness of the 1 st intermediate layer" means the thickness of the entire 1 st intermediate layer, and for example, the thickness of the 1 st intermediate layer composed of a plurality of layers means the total thickness of all the layers constituting the 1 st intermediate layer.

< composition for Forming intermediate layer > < 1 st >

The 1 st intermediate layer can be formed using the 1 st intermediate layer-forming composition containing the constituent material thereof.

For example, the 1 st intermediate layer can be formed on a target portion by applying the 1 st intermediate layer-forming composition to the surface to be formed of the 1 st intermediate layer and drying it as necessary, or curing it by irradiation with an energy ray. A more specific method for forming the 1 st intermediate layer will be described in detail later together with the formation method of the other layers. The content ratio of the components that do not vaporize at room temperature in the composition for forming the 1 st intermediate layer is generally the same as the content ratio of the components of the 1 st intermediate layer. Here, the "normal temperature" is as described above.

The coating of the composition for forming an intermediate layer 1 may be carried out by a known method, and examples thereof include methods using various coaters such as an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a knife coater, a curtain coater, a die coater, a knife coater, a screen coater, a meyer bar coater, and a kiss coater.

The drying conditions of the composition for forming the 1 st intermediate layer are not particularly limited, but when the composition for forming the 1 st intermediate layer contains a solvent described later, it is preferably dried by heating, and in this case, it is preferably dried at, for example, 70 to 130 ℃ for 10 seconds to 5 minutes.

When the composition for forming an intermediate layer 1 has energy ray curability, it is preferable that the composition is further cured by irradiation with energy rays after drying.

Examples of the composition for forming the 1 st intermediate layer include: and a urethane (meth) acrylate-containing composition (II-1) for forming an intermediate layer 1.

< composition for Forming intermediate layer (II-1) >

As described above, the composition (II-1) for forming an intermediate layer 1 contains a urethane (meth) acrylate.

[ urethane (meth) acrylate ]

The urethane (meth) acrylate is a compound having at least a (meth) acryloyl group and a urethane bond in 1 molecule, and has energy ray polymerizability.

The urethane (meth) acrylate may be a monofunctional urethane (meth) acrylate (a urethane (meth) acrylate having only 1 (meth) acryloyl group in 1 molecule) or a polyfunctional urethane (meth) acrylate (a urethane (meth) acrylate having 2 or more (meth) acryloyl groups in 1 molecule) which is a bifunctional urethane (meth) acrylate, but it is preferable to use at least a monofunctional urethane (meth) acrylate.

Examples of the urethane (meth) acrylate contained in the composition for forming an intermediate layer 1 include: urethane (meth) acrylate obtained by further reacting a (meth) acrylic compound having a hydroxyl group and a (meth) acryloyl group with an isocyanate-terminated urethane prepolymer obtained by reacting a polyol compound and a polyisocyanate compound. Here, the "isocyanate-terminated urethane prepolymer" refers to a prepolymer having a urethane bond and an isocyanate group at a molecular terminal portion.

The urethane (meth) acrylate contained in the composition (II-1) for forming an intermediate layer 1 may be only one kind, or two or more kinds. When the urethane (meth) acrylate contained in the 1 st intermediate layer forming composition (II-1) is two or more, the combination and ratio thereof can be arbitrarily selected.

(polyol compound)

The polyol compound is not particularly limited as long as it is a compound having 2 or more hydroxyl groups in 1 molecule.

The polyhydric alcohol compound may be used alone or in combination of two or more. When two or more of the polyol compounds are used in combination, the combination and ratio thereof can be arbitrarily selected.

Examples of the polyol compound include: alkylene glycol, polyether polyol, polyester polyol, polycarbonate polyol and the like.

The polyol compound may be any of bifunctional diols, trifunctional triols, tetrafunctional or higher polyols, and the like, and is preferably a diol in view of easy availability, excellent versatility, excellent reactivity, and the like.

Polyether polyol

The polyether polyol is not particularly limited, but is preferably a polyether diol, and examples of the polyether diol include compounds represented by the following general formula (1).

[ chemical formula 1]

(in the formula, n is an integer of 2 or more; R is a 2-valent hydrocarbon group, and R's may be the same or different from each other.)

In the formula, n represents the number of repeating units of the group represented by the general formula "-R-O-" and is not particularly limited as long as it is an integer of 2 or more. Wherein n is preferably 10 to 250, more preferably 25 to 205, and particularly preferably 40 to 185.

In the formula, R is not particularly limited as long as it is a 2-valent hydrocarbon group, but is preferably an alkylene group, more preferably an alkylene group having 1 to 6 carbon atoms, yet more preferably an ethylene group, a propylene group or a tetramethylene group, and particularly preferably a propylene group or a tetramethylene group.

The compound represented by the above formula (1) is preferably polyethylene glycol, polypropylene glycol or polytetramethylene glycol, and more preferably polypropylene glycol or polytetramethylene glycol.

By reacting the polyether diol with the polyisocyanate compound, a prepolymer having an ether bond represented by the following general formula (1a) can be obtained as the isocyanate-terminated urethane prepolymer. Further, by using such a terminal isocyanate urethane prepolymer, the urethane (meth) acrylate becomes a urethane (meth) acrylate having the ether bond, that is, a urethane (meth) acrylate having a structural unit derived from the polyether diol.

[ chemical formula 2]

(wherein R and n are the same as defined above.)

Polyester polyols

The polyester polyol is not particularly limited, and examples thereof include polyols obtained by an esterification reaction using a polybasic acid or a derivative thereof. The "derivative" in the present embodiment means a compound in which 1 or more groups of the original compound are substituted with a group (substituent) other than the above groups, unless otherwise specified. Here, the "group" includes not only an atomic group in which a plurality of atoms are bonded but also 1 atom.

Examples of the polybasic acid and the derivative thereof include: polybasic acids and derivatives thereof, which are generally used as raw materials for producing polyesters.

Examples of the polybasic acid include: saturated aliphatic polybasic acids, unsaturated aliphatic polybasic acids, aromatic polybasic acids, and the like, and dimer acids corresponding to any of these polybasic acids may also be used.

Examples of the saturated aliphatic polybasic acid include: and saturated aliphatic dibasic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid.

Examples of the unsaturated aliphatic polybasic acid include: unsaturated aliphatic dibasic acids such as maleic acid and fumaric acid.

Examples of the aromatic polybasic acid include: aromatic dibasic acids such as phthalic acid, isophthalic acid, terephthalic acid, and 2, 6-naphthalenedicarboxylic acid; aromatic tribasic acids such as trimellitic acid; aromatic tetrabasic acids such as pyromellitic acid, and the like.

Examples of the derivatives of the polybasic acids include: anhydrides of the above-mentioned saturated aliphatic polybasic acids, unsaturated aliphatic polybasic acids and aromatic polybasic acids, and hydrogenated dimer acids.

The polybasic acids or derivatives thereof may be used alone or in combination of two or more. When two or more of the above polybasic acids or derivatives thereof are used in combination, the combination and ratio thereof can be arbitrarily selected.

The polybasic acid is preferably an aromatic polybasic acid from the viewpoint of being suitable for forming a coating film having an appropriate hardness.

In the esterification reaction for obtaining the polyester polyol, a known catalyst may be used as needed.

Examples of the catalyst include: tin compounds such as dibutyltin oxide and stannous octoate; titanium alkoxides such as tetrabutyl titanate and tetrapropyl titanate.

Polycarbonate polyols

The polycarbonate polyol is not particularly limited, and examples thereof include polyols obtained by reacting the same diol as the compound represented by the above formula (1) with an alkylene carbonate.

Here, the diol and the alkylene carbonate may be used singly or in combination of two or more. When two or more of the diol and the alkylene carbonate are used in combination, the combination and ratio thereof may be arbitrarily selected.

The number average molecular weight calculated from the hydroxyl value of the polyol compound is preferably 1000 to 10000, more preferably 2000 to 9000, and particularly preferably 3000 to 7000. When the number average molecular weight is 1000 or more, excessive formation of urethane bonds can be suppressed, and control of the viscoelastic properties of the 1 st intermediate layer can be facilitated. In addition, by setting the number average molecular weight to 10000 or less, excessive softening of the 1 st intermediate layer can be suppressed.

The above number average molecular weight calculated from the hydroxyl value of the polyol compound is a value calculated from the following formula.

[ number average molecular weight of polyol compound ] - [ number of functional groups of polyol compound ]. times.56.11X 1000/[ hydroxyl value of polyol compound (unit: mgKOH/g) ]

The polyol compound is preferably a polyether polyol, and more preferably a polyether diol.

(polyisocyanate Compound)

The polyisocyanate compound to be reacted with the polyol compound is not particularly limited as long as it is a compound having 2 or more isocyanate groups.

One kind of polyisocyanate compound may be used alone, or two or more kinds may be used in combination. When two or more polyisocyanate compounds are used in combination, the combination and ratio thereof can be arbitrarily selected.

Examples of the polyisocyanate compound include: chain aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate; cyclic aliphatic diisocyanates such as isophorone diisocyanate, norbornane diisocyanate, dicyclohexylmethane-4, 4 ' -diisocyanate, dicyclohexylmethane-2, 4 ' -diisocyanate, and ω, ω ' -diisocyanate dimethylcyclohexane; and aromatic diisocyanates such as 4, 4' -diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, dimethylbiphenyl diisocyanate, tetramethylene xylylene diisocyanate, and naphthalene-1, 5-diisocyanate.

Among these, the polyisocyanate compound is preferably isophorone diisocyanate, hexamethylene diisocyanate or xylylene diisocyanate in view of handling properties.

((meth) acrylic acid compound)

The (meth) acrylic compound to be reacted with the isocyanate-terminated urethane prepolymer is not particularly limited as long as it has at least a hydroxyl group and a (meth) acryloyl group in 1 molecule.

The (meth) acrylic compound may be used alone or in combination of two or more. When two or more of the above (meth) acrylic compounds are used in combination, the combination and ratio thereof can be arbitrarily selected.

Examples of the (meth) acrylic compound include: hydroxyl group-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 5-hydroxycyclooctyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate, polyethylene glycol mono (meth) acrylate, and polypropylene glycol mono (meth) acrylate; hydroxyl group-containing (meth) acrylamides such as N-methylol (meth) acrylamide; and a reaction product obtained by reacting vinyl alcohol, vinyl phenol, or bisphenol a diglycidyl ether with (meth) acrylic acid.

Among these, the (meth) acrylic compound is preferably a hydroxyl group-containing (meth) acrylate, more preferably a hydroxyl group-containing alkyl (meth) acrylate, and particularly preferably 2-hydroxyethyl (meth) acrylate.

The reaction of the terminal isocyanate urethane prepolymer with the (meth) acrylic compound may be carried out using a solvent, a catalyst, or the like as needed.

The conditions for reacting the isocyanate-terminated urethane prepolymer with the (meth) acrylic compound may be appropriately adjusted, and for example, the reaction temperature is preferably 60 to 100 ℃ and the reaction time is preferably 1 to 4 hours.

The urethane (meth) acrylate may be any of an oligomer, a polymer, and a mixture of an oligomer and a polymer, and is preferably an oligomer.

For example, the weight average molecular weight of the urethane (meth) acrylate is preferably 1000 to 100000, more preferably 3000 to 80000, and particularly preferably 5000 to 65000. By setting the weight average molecular weight of the urethane (meth) acrylate to 1000 or more, the hardness of the 1 st intermediate layer can be easily optimized based on the intermolecular force between the structures derived from the urethane (meth) acrylate in the polymer formed from the urethane (meth) acrylate and the polymerizable monomer described later.

In the present embodiment, the weight average molecular weight is a polystyrene equivalent value measured by a Gel Permeation Chromatography (GPC) method unless otherwise specified.

[ polymerizable monomer ]

From the viewpoint of further improving the film-forming property, the composition (II-1) for forming an intermediate layer may contain a polymerizable monomer in addition to the urethane (meth) acrylate.

The polymerizable monomer is preferably a compound having energy ray polymerizability and having at least 1 (meth) acryloyl group in 1 molecule, excluding oligomers and polymers having a weight average molecular weight of 1000 or more.

Examples of the polymerizable monomer include: an alkyl (meth) acrylate in which the alkyl group constituting the alkyl ester is a chain alkyl group having 1 to 30 carbon atoms; a functional group-containing (meth) acrylic compound having a functional group such as a hydroxyl group, an amide group, an amino group, or an epoxy group; (meth) acrylate having an alicyclic group; (meth) acrylate having an aromatic hydrocarbon group; (meth) acrylate having a heterocyclic group; a compound having a vinyl group; compounds having allyl groups, and the like.

Examples of the alkyl (meth) acrylate having a chain alkyl group having 1 to 30 carbon atoms include: methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, 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, lauryl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, myristyl (meth) acrylate, Pentadecyl (meth) acrylate, hexadecyl (meth) acrylate (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), isostearyl (meth) acrylate (isostearyl (meth) acrylate), nonadecyl (meth) acrylate, eicosyl (meth) acrylate, and the like.

Examples of the functional group-containing (meth) acrylic acid derivative include: hydroxyl group-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate; (meth) acrylamides and derivatives thereof such as (meth) acrylamide, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide, N-methoxymethyl (meth) acrylamide, and N-butoxymethyl (meth) acrylamide; a (meth) acrylate having an amino group (hereinafter, sometimes referred to as "amino group-containing (meth) acrylate"); a (meth) acrylate having a monosubstituted amino group in which 1 hydrogen atom of the amino group is substituted with a group other than a hydrogen atom (hereinafter, also referred to as a "monosubstituted amino group-containing (meth) acrylate" in some cases); a (meth) acrylate having a disubstituted amino group in which 2 hydrogen atoms of an amino group are substituted with a group other than a hydrogen atom (hereinafter, also referred to as a "disubstituted amino group-containing (meth) acrylate"); and (meth) acrylates having an epoxy group (hereinafter, also referred to as "epoxy group-containing (meth) acrylates") such as glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate.

Here, the term "amino group-containing (meth) acrylate" means that 1 or 2 or more hydrogen atoms of the (meth) acrylate are substituted with amino groups (-NH)₂) A compound obtained by substitution. Similarly, "a (meth) acrylate containing a mono-substituted amino group" refers to a compound in which 1 or 2 or more hydrogen atoms of a (meth) acrylate are substituted with a mono-substituted amino group, and "a (meth) acrylate containing a di-substituted amino group" refers to a compound in which 1 or 2 or more hydrogen atoms of a (meth) acrylate are substituted with a di-substituted amino group.

Examples of the group other than the hydrogen atom in the "mono-substituted amino group" and the "di-substituted amino group" (i.e., a substituent) include an alkyl group and the like.

Examples of the (meth) acrylate having an alicyclic group include: isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, adamantyl (meth) acrylate, and the like.

Examples of the aromatic hydrocarbon group-containing (meth) acrylate include: phenylhydroxypropyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, and the like.

The heterocyclic group in the (meth) acrylate having a heterocyclic group may be any of an aromatic heterocyclic group and an aliphatic heterocyclic group.

Examples of the (meth) acrylate having the heterocyclic group include: tetrahydrofurfuryl (meth) acrylate, or (meth) acryloylmorpholine.

Examples of the compound having a vinyl group include: styrene, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, N-vinylformamide, N-vinylpyrrolidone, N-vinylcaprolactam, and the like.

Examples of the compound having an allyl group include: allyl glycidyl ether, and the like.

The polymerizable monomer preferably has a bulky group in view of good compatibility with the urethane (meth) acrylate. Examples of the polymerizable monomer include (meth) acrylates having an alicyclic group, (meth) acrylates having an aromatic hydrocarbon group, and (meth) acrylates having a heterocyclic group, and more preferably (meth) acrylates having an alicyclic group.

The polymerizable monomer contained in the composition (II-1) for forming an intermediate layer 1 may be only one type, or two or more types. When two or more polymerizable monomers are contained in the composition (II-1) for forming an intermediate layer 1, the combination and ratio of the two polymerizable monomers can be arbitrarily selected.

In the composition (II-1) for forming the intermediate layer 1, the content of the polymerizable monomer is preferably 10 to 99% by mass, more preferably 15 to 95% by mass, still more preferably 20 to 90% by mass, and particularly preferably 25 to 80% by mass, based on the total mass of the composition (II-1) for forming the intermediate layer 1.

[ photopolymerization initiator ]

The composition (II-1) for forming an intermediate layer may contain a photopolymerization initiator in addition to the urethane (meth) acrylate and the polymerizable monomer. The 1 st intermediate layer forming composition (II-1) containing a photopolymerization initiator sufficiently progresses the curing reaction even when irradiated with energy rays of relatively low energy such as ultraviolet rays.

The photopolymerization initiator in the composition (II-1) for forming the intermediate layer 1 may be the same as the photopolymerization initiator in the adhesive composition (I-1) 1.

The number of photopolymerization initiators contained in the composition (II-1) for forming an intermediate layer 1 may be one, or two or more. When two or more kinds of photopolymerization initiators are contained in the composition (II-1) for forming an intermediate layer 1, the combination and ratio of these initiators can be arbitrarily selected.

In the composition (II-1) for forming an intermediate layer 1, the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass, based on 100 parts by mass of the total content of the urethane (meth) acrylate and the polymerizable monomer.

[ resin component other than urethane (meth) acrylate ]

The composition (II-1) for forming an intermediate layer 1 may contain a resin component other than the urethane (meth) acrylate within a range not to impair the effects of the present invention.

The kind of the resin component and the content thereof in the 1 st intermediate layer forming composition (II-1) may be appropriately selected depending on the purpose, and is not particularly limited.

[ other additives ]

The composition (II-1) for forming an intermediate layer 1 may contain other additives not included in the above-mentioned components within a range not to impair the effects of the present invention.

Examples of the other additives include: known additives such as a crosslinking agent, an antistatic agent, an antioxidant, a chain transfer agent, a softener (plasticizer), a filler, a rust preventive, and a colorant (pigment and dye).

For example, the chain transfer agent may be a thiol compound having at least 1 thiol (mercapto) group in 1 molecule.

Examples of the thiol compound include: nonanethiol, 1-dodecanethiol, 1, 2-ethanedithiol, 1, 3-propanedithiol, triazine thiol, triazine dithiol, triazine trithiol, 1,2, 3-propanetrithiol, tetraethylene glycol bis (3-mercaptopropionate), trimethylolpropane tris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetramercaptoacetate, dipentaerythritol hexa (3-mercaptopropionate), tris [ (3-mercaptopropionyloxy) ethyl ] isocyanurate, 1, 4-bis (3-mercaptobutyryloxy) butane, pentaerythritol tetrakis (3-mercaptobutyrate), 1,3, 5-tris (3-mercaptobutoxyethyl) -1,3, 5-triazine-2, 4,6- (1H,3H,5H) -triones, and the like.

The number of other additives contained in the composition (II-1) for forming an intermediate layer of the formula 1 may be only one, or two or more. When two or more other additives are contained in the composition (II-1) for forming an intermediate layer of the formula 1, the combination and ratio of these additives can be arbitrarily selected.

The content of the other additives in the composition (II-1) for forming an intermediate layer 1 is not particularly limited, and may be appropriately selected depending on the kind thereof.

[ solvent ]

The composition (II-1) for forming an intermediate layer of claim 1 may contain a solvent. The composition (II-1) for forming an intermediate layer 1 contains a solvent, and thus the coating suitability with respect to the surface to be coated is improved.

< method for producing composition for forming intermediate layer > < method for producing intermediate layer >

The composition for forming an intermediate layer 1 may be obtained by blending the components for constituting the composition for forming an intermediate layer 1 such as the composition (II-1) for forming an intermediate layer 1.

The order of addition of the components is not particularly limited, and two or more components may be added simultaneously.

When a solvent is used, the solvent may be mixed with any compounding ingredient other than the solvent to dilute the compounding ingredient in advance and then used, or the solvent may be mixed with any compounding ingredient other than the solvent to use without diluting the compounding ingredient in advance.

The method of mixing the components at the time of blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer, a paddle, or the like, a method of mixing using a mixer, and a method of mixing by applying ultrasonic waves.

The temperature and time at the time of addition and mixing of each component are not particularly limited as long as each component is not deteriorated, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ℃.

Very good thermosetting resin layer

The thermosetting resin layer is a layer for protecting the circuit surface of the semiconductor wafer and the bumps provided on the circuit surface, and the 1 st protective film is formed by curing.

A preferable thermosetting resin layer includes, for example, a thermosetting resin layer containing a polymer component (a) and a thermosetting component (B). The polymer component (a) can be considered to be a component formed by a polymerization reaction of a polymerizable compound. The thermosetting component (B) is a component capable of undergoing a curing (polymerization) reaction using heat as a trigger of the reaction. In the present invention, the polymerization reaction also includes a polycondensation reaction.

The thermosetting resin layer may be composed of only one layer (single layer) or may be composed of a plurality of layers of two or more layers. When the thermosetting resin layer is 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 thermosetting resin layer is preferably 1 to 100 μm, more preferably 5 to 75 μm, and particularly preferably 5 to 50 μm. By setting the thickness of the thermosetting resin layer to the above lower limit or more, the 1 st protective film having higher protective ability can be formed. In addition, by setting the thickness of the thermosetting resin layer to the above upper limit or less, the effect of suppressing the bubble inclusion of the 1 st protective film can be further improved.

Here, the "thickness of the thermosetting resin layer" means the thickness of the entire thermosetting resin layer, and for example, the thickness of the thermosetting resin layer composed of a plurality of layers means the total thickness of all layers constituting the thermosetting resin layer.

< composition for Forming thermosetting resin layer >)

The thermosetting resin layer can be formed using a composition for forming a thermosetting resin layer containing a constituent material thereof. For example, a thermosetting resin layer can be formed on a desired portion by applying a thermosetting resin layer forming composition to a surface to be formed of a thermosetting resin layer and drying the composition as necessary. The content ratio of the components that do not vaporize at room temperature in the composition for forming a thermosetting resin layer is generally the same as the content ratio of the components of the thermosetting resin layer. Here, "normal temperature" is as described above.

The thermosetting resin layer-forming composition may be applied by a known method, and examples thereof include methods using various coaters such as an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a knife coater, a curtain coater, a die coater, a knife coater, a screen coater, a meyer bar coater, and a kiss coater.

The drying condition of the thermosetting resin layer-forming composition is not particularly limited, but when the thermosetting resin layer-forming composition contains a solvent described later, it is preferably dried by heating, and in this case, it is preferably dried under the condition of, for example, 10 seconds to 5 minutes at 70 to 130 ℃.

< composition for Forming resin layer (III-1) >

Examples of the composition for forming a thermosetting resin layer include: a thermosetting resin layer-forming composition (III-1) containing a polymer component (A) and a thermosetting component (B) (in the present embodiment, also referred to simply as "resin layer-forming composition (III-1)"), and the like.

[ Polymer component (A) ]

The polymer component (a) is a polymer compound for imparting film formability, flexibility, and the like to the thermosetting resin layer.

The polymer component (a) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be one type or two or more types. When the polymer component (a) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer is two or more, the combination and ratio thereof can be arbitrarily selected.

Examples of the polymer component (a) include: an acrylic resin (a resin having a (meth) acryloyl group), a polyester, a urethane resin (a resin having a urethane bond), an acrylic urethane resin, a silicone resin (a resin having a siloxane bond), a rubber resin (a resin having a rubber structure), a phenoxy resin, a thermosetting polyimide, or the like, and an acrylic resin is preferable.

As the acrylic resin in the polymer component (a), a known acrylic polymer can be mentioned.

The weight average molecular weight (Mw) of the acrylic resin is preferably 10000 to 2000000, more preferably 100000 to 1500000. When the weight average molecular weight of the acrylic resin is not less than the above lower limit, the shape stability (stability with time during storage) of the thermosetting resin layer is improved. Further, when the weight average molecular weight of the acrylic resin is not more than the above upper limit, the thermosetting resin layer easily follows the uneven surface of the adherend.

The glass transition temperature (Tg) of the acrylic resin is preferably-60 to 70 ℃, more preferably-30 to 50 ℃. When the Tg of the acrylic resin is not less than the lower limit value, the adhesion between the 1 st protective film and the 1 st supporting sheet is suppressed, and the peelability of the 1 st supporting sheet is improved. When the Tg of the acrylic resin is not more than the above upper limit, the adhesive strength between the acrylic resin and the adherend of the thermosetting resin layer and the 1 st protective film is improved.

Examples of the acrylic resin include: one or two or more polymers of (meth) acrylic acid esters; and copolymers of two or more monomers selected from (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide.

Examples of the (meth) acrylic acid ester constituting the acrylic resin include: methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, 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, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, myristyl (meth) acrylate, Alkyl (meth) acrylates in which the alkyl group constituting the alkyl ester is a chain structure having 1 to 18 carbon atoms, such as pentadecyl (meth) acrylate, hexadecyl (meth) acrylate ((palm (meth) acrylate)), heptadecyl (meth) acrylate, and octadecyl (meth) acrylate ((stearyl (meth) acrylate);

cycloalkyl (meth) acrylates such as isobornyl (meth) acrylate and dicyclopentanyl (meth) acrylate;

aralkyl (meth) acrylates such as benzyl (meth) acrylate;

cycloalkenyl (meth) acrylates such as dicyclopentenyl (meth) acrylate;

cycloalkenyloxyalkyl (meth) acrylates such as dicyclopentenyloxyethyl (meth) acrylate;

(meth) acrylic acid imide;

glycidyl group-containing (meth) acrylates such as glycidyl (meth) acrylate;

hydroxyl group-containing (meth) acrylates such as hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate;

and substituted amino group-containing (meth) acrylates such as N-methylaminoethyl (meth) acrylate. Here, the "substituted amino group" refers to a group in which 1 or 2 hydrogen atoms of an amino group are substituted with a group other than a hydrogen atom.

The acrylic resin may be obtained by copolymerizing the above (meth) acrylic acid ester and one or more monomers other than the (meth) acrylic acid ester selected from the group consisting of (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide.

The acrylic resin may be composed of only one monomer, or two or more monomers. When two or more monomers constituting the acrylic resin are used, the combination and ratio of the monomers can be arbitrarily selected.

The acrylic resin may have a functional group capable of bonding to another compound, such as a vinyl group, a (meth) acryloyl group, an amino group, a hydroxyl group, a carboxyl group, or an isocyanate group. The functional group of the acrylic resin may be bonded to another compound via a crosslinking agent (F) described later, or may be directly bonded to another compound without the crosslinking agent (F). By bonding the acrylic resin to another compound using the functional group, the reliability of the package obtained using the protective film-forming sheet tends to be improved.

In the present invention, as the polymer component (a), a thermoplastic resin other than an acrylic resin (hereinafter, may be simply referred to as "thermoplastic resin") may be used alone without using an acrylic resin, or a thermoplastic resin other than an acrylic resin may be used in combination with an acrylic resin. By using the thermoplastic resin, the releasability of the 1 st protective film from the 1 st backup sheet may be improved, or the thermosetting resin layer may be made to easily follow the uneven surface of the adherend.

The weight average molecular weight of the thermoplastic resin is preferably 1000 to 100000, more preferably 3000 to 80000.

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

Examples of the thermoplastic resin include: polyester, polyurethane, phenoxy resin, polybutylene, polybutadiene, polystyrene, and the like.

The thermoplastic resin contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be one type or two or more types. When the thermoplastic resin contained in the resin layer-forming composition (III-1) and the thermosetting resin layer is two or more, the combination and ratio thereof can be arbitrarily selected.

In the resin layer-forming composition (III-1), the proportion of the content of the polymer component (a) relative to the total content of all components other than the solvent (i.e., the content of the polymer component (a) in the thermosetting resin layer) does not depend on the kind of the polymer component (a), and is preferably 5 to 85 mass%, more preferably 5 to 80 mass%.

The polymer component (a) may correspond to the thermosetting component (B). In the present invention, when the resin layer-forming composition (III-1) contains such components corresponding to both the polymer component (A) and the thermosetting component (B), it is considered that the resin layer-forming composition (III-1) contains the polymer component (A) and the thermosetting component (B).

[ thermosetting component (B) ]

The thermosetting component (B) is a component for curing the thermosetting resin layer to form a hard 1 st protective film.

The thermosetting component (B) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be one kind or two or more kinds. When the thermosetting component (B) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer is two or more, the combination and ratio thereof can be arbitrarily selected.

Examples of the thermosetting component (B) include: epoxy thermosetting resins, thermosetting polyimides, polyurethanes, unsaturated polyesters, silicone resins, and the like, and epoxy thermosetting resins are preferred.

(epoxy thermosetting resin)

The epoxy thermosetting resin includes an epoxy resin (B1) and a thermosetting agent (B2).

The epoxy thermosetting resin contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be one type or two or more types. When two or more epoxy thermosetting resins are contained in the resin layer-forming composition (III-1) and the thermosetting resin layer, the combination and ratio thereof can be arbitrarily selected.

Epoxy resin (B1)

Examples of the epoxy resin (B1) include known epoxy resins, and examples thereof include: polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and hydrogenated products thereof, o-cresol novolac epoxy resins, dicyclopentadiene epoxy resins, biphenyl epoxy resins, bisphenol A epoxy resins, bisphenol F epoxy resins, phenylene skeleton epoxy resins, and other bifunctional or higher epoxy compounds.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group may 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 having an unsaturated hydrocarbon group, the reliability of the package obtained by using the sheet for forming a protective film is improved.

Examples of the epoxy resin having an unsaturated hydrocarbon group include: a compound in which a part of the epoxy groups of the polyfunctional epoxy resin is converted into a group having an unsaturated hydrocarbon group. Such a compound can be obtained, for example, by addition reaction of (meth) acrylic acid or a derivative thereof with an epoxy group.

Examples of the epoxy resin having an unsaturated hydrocarbon group include: and compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting an epoxy resin.

The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include vinyl group (vinyl group, ethyl group), 2-propenyl group (allyl group), (meth) acryloyl group, (meth) acrylamido group, and the like, and acryloyl group is preferable.

The number average molecular weight of the epoxy resin (B1) is not particularly limited, but is preferably 300 to 30000, more preferably 400 to 10000, and particularly preferably 500 to 3000, in view of curability of the thermosetting resin layer and strength and heat resistance of the 1 st protective film after curing.

In the present specification, the "number average molecular weight" is a polystyrene equivalent value measured by a Gel Permeation Chromatography (GPC) method unless otherwise specified.

The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1000g/eq, more preferably 300 to 800 g/eq.

In the present specification, "epoxy equivalent" means the number of grams (g/eq) of an epoxy compound containing 1 gram equivalent of an epoxy group, and can be determined in accordance with JIS K7236: 2001 were measured by the method of the above publication.

The epoxy resin (B1) may be used alone or in combination of two or more. When two or more kinds of the epoxy resins (B1) are used in combination, the combination and ratio thereof can be arbitrarily selected.

Heat-curing agent (B2)

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

Examples of the thermosetting agent (B2) include: a compound having 2 or more functional groups capable of reacting with an epoxy group in 1 molecule. Examples of the functional group include: and a group obtained by forming an acid anhydride of a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, or an acid group, and the like, preferably a group obtained by forming an acid anhydride of a phenolic hydroxyl group, an amino group, or an acid group, and more preferably a phenolic hydroxyl group or an amino group.

Examples of the phenolic curing agent having a phenolic hydroxyl group in the thermosetting agent (B2) include: multifunctional phenol resins, biphenols, novolak-type phenol resins, dicyclopentadiene-type phenol resins, aralkyl phenol resins, and the like.

Examples of the amine-based curing agent having an amino group in the thermosetting agent (B2) include: dicyandiamide (hereinafter also referred to simply as "DICY" in some cases) and the like.

The heat-curing agent (B2) may be a heat-curing agent having an unsaturated hydrocarbon group.

Examples of the heat-curing agent (B2) having an unsaturated hydrocarbon group include: a compound in which a part of the hydroxyl groups of the phenol resin is substituted with a group having an unsaturated hydrocarbon group, a compound in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring of the phenol resin, or the like.

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

When a phenol-based curing agent is used as the thermosetting agent (B2), the thermosetting agent (B2) is preferably a thermosetting agent having a high softening point or glass transition temperature in order to improve the peelability of the 1 st protective film from the 1 st supporting sheet.

The number average molecular weight of the resin component such as the polyfunctional phenol resin, the novolak phenol resin, the dicyclopentadiene phenol resin, or the aralkyl phenol resin in the thermosetting agent (B2) is preferably 300 to 30000, more preferably 400 to 10000, and particularly preferably 500 to 3000.

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

The heat-curing agent (B2) may be used alone or in combination of two or more. When two or more of the thermosetting agents (B2) are used in combination, the combination and ratio thereof can be arbitrarily selected.

The content of the thermosetting agent (B2) in the resin layer-forming composition (III-1) and the thermosetting resin layer is preferably 0.1 to 500 parts by mass, more preferably 1 to 200 parts by mass, per 100 parts by mass of the content of the epoxy resin (B1). When the content of the thermosetting agent (B2) is not less than the lower limit value, the thermosetting resin layer can be more easily cured. When the content of the thermosetting agent (B2) is not more than the above upper limit, the moisture absorption rate of the thermosetting resin layer is reduced, and the reliability of the package obtained by using the protective film-forming sheet is further improved.

In the resin layer-forming composition (III-1) and the thermosetting resin layer, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is preferably 50 to 1000 parts by mass, more preferably 100 to 900 parts by mass, and particularly preferably 150 to 800 parts by mass, relative to 100 parts by mass of the content of the polymer component (a). When the content of the thermosetting component (B) is in such a range, the adhesion between the 1 st protective film and the 1 st supporting sheet is suppressed, and the peelability of the 1 st supporting sheet is improved.

[ curing Accelerator (C) ]

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

Preferred examples of the curing accelerator (C) include: tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol; imidazoles (imidazole in which 1 or more hydrogen atoms are replaced with a group other than a hydrogen atom) such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4, 5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole; organic phosphines (phosphine in which 1 or more hydrogen atoms are substituted with an organic group), such as tributylphosphine, diphenylphosphine, and triphenylphosphine; tetraphenyl radical

Tetraphenylborate such as tetraphenylborate and triphenylphosphine tetraphenylborate.

The curing accelerator (C) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be one kind or two or more kinds. When the curing accelerator (C) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer is two or more, the combination and ratio thereof can be arbitrarily selected.

When the curing accelerator (C) is used, the content of the curing accelerator (C) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, based on 100 parts by mass of the content of the thermosetting component (B) in the resin layer-forming composition (III-1) and the thermosetting resin layer. By setting the content of the curing accelerator (C) to the lower limit value or more, the effects of using the curing accelerator (C) can be more remarkably obtained. When the content of the curing accelerator (C) is not more than the above upper limit, for example, the effect of suppressing the occurrence of segregation by the highly polar curing accelerator (C) moving to the side of the adhesion interface with the adherend in the thermosetting resin layer under high temperature/high humidity conditions is improved, and the reliability of the package obtained using the protective film forming sheet is further improved.

[ Filler (D) ]

The resin layer-forming composition (III-1) and the thermosetting resin layer may contain a filler (D). By containing the filler (D) in the thermosetting resin layer, the thermal expansion coefficient of the 1 st protective film obtained by curing the thermosetting resin layer can be easily adjusted, and the reliability of the package obtained using the protective film-forming sheet can be further improved by optimizing the thermal expansion coefficient with respect to the object to be formed of the 1 st protective film. Further, by containing the filler (D) in the thermosetting resin layer, the moisture absorption rate of the 1 st protective film can be reduced, and the heat dissipation property can be improved.

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

Preferred inorganic fillers include, for example: powders of silica, alumina, talc, calcium carbonate, titanium white, iron oxide red, silicon carbide, boron nitride, and the like; forming the inorganic filler into spherical beads; surface-modified products of these inorganic fillers; single crystal fibers of these inorganic filler materials; glass fibers, and the like.

Of these materials, the inorganic filler material is preferably silica or alumina.

The filler (D) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be one type or two or more types. When the number of the filler (D) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer is two or more, the combination and ratio thereof can be arbitrarily selected.

When the filler (D) is used, the content of the filler (D) (i.e., the content of the filler (D) in the thermosetting resin layer) in the resin layer-forming composition (III-1) is preferably 5 to 35% by mass, more preferably 7 to 25% by mass, based on the total content of all components other than the solvent.

[ coupling agent (E) ]

The resin layer-forming composition (III-1) and the thermosetting resin layer may contain a coupling agent (E). By using a compound having a functional group capable of reacting with an inorganic compound or an organic compound as the coupling agent (E), the adhesiveness and adhesion of the thermosetting resin layer to the adherend can be improved. In addition, by using the coupling agent (E), the heat resistance of the 1 st protective film obtained by curing the thermosetting resin layer is not impaired, and the water resistance can be improved.

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

Preferred examples of the silane coupling agent include: 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxymethyldiethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxysilane, 3- (2-aminoethylamino) propylmethyldiethoxysilane, 3- (phenylamino) propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and the like, Bis (3-triethoxysilylpropyl) tetrasulfide, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazolesilane and the like.

The coupling agent (E) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be one kind or two or more kinds. When the coupling agent (E) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer is two or more, the combination and ratio thereof can be arbitrarily selected.

When the coupling agent (E) is used, the content of the coupling agent (E) is 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, based on 100 parts by mass of the total content of the polymer component (a) and the thermosetting component (B) in the resin layer-forming composition (III-1) and the thermosetting resin layer. When the content of the coupling agent (E) is not less than the lower limit described above, the effects of using the coupling agent (E) such as improvement in dispersibility of the filler (D) in the resin and improvement in adhesion between the thermosetting resin layer and the adherend can be more remarkably obtained. Further, by setting the content of the coupling agent (E) to the upper limit value or less, the occurrence of outgassing (outgas) can be further suppressed.

[ crosslinking agent (F) ]

When the polymer component (a) is a component having a functional group such as a vinyl group, (meth) acryloyl group, amino group, hydroxyl group, carboxyl group, or isocyanate group which can be bonded to another compound, such as the acrylic resin, the resin layer-forming composition (III-1) and the thermosetting resin layer may contain a crosslinking agent (F) for crosslinking the functional group by bonding to another compound. The initial adhesion and cohesion of the thermosetting resin layer can be adjusted by crosslinking with the crosslinking agent (F).

Examples of the crosslinking agent (F) include: an organic polyisocyanate compound, an organic polyimine compound, a metal chelate-based crosslinking agent (a crosslinking agent having a metal chelate structure), an aziridine-based crosslinking agent (a crosslinking agent having an aziridine group), and the like.

Examples of the organic polyisocyanate compound include: an aromatic polyisocyanate compound, an aliphatic polyisocyanate compound, and an alicyclic polyisocyanate compound (hereinafter, these compounds may be collectively referred to simply as "aromatic polyisocyanate compound or the like"); trimers, isocyanurates and adducts such as the aromatic polyisocyanate compounds; and isocyanate-terminated urethane prepolymers obtained by reacting the aromatic polyisocyanate compound and the like with a polyol compound. The "adduct" is a reaction product of the aromatic polyisocyanate compound, the aliphatic polyisocyanate compound or the alicyclic polyisocyanate compound with a low-molecular active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil, and examples thereof include a xylylene diisocyanate adduct of trimethylolpropane described later. In addition, the "terminal isocyanate urethane prepolymer" is as described previously.

More specifically, the organic polyisocyanate compound includes, for example: 2, 4-toluene diisocyanate; 2, 6-toluene diisocyanate; 1, 3-xylylene diisocyanate; 1, 4-xylene diisocyanate; diphenylmethane-4, 4' -diisocyanate; diphenylmethane-2, 4' -diisocyanate; 3-methyl diphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4, 4' -diisocyanate; dicyclohexylmethane-2, 4' -diisocyanate; a compound obtained by adding one or more of toluene diisocyanate, hexamethylene diisocyanate and xylylene diisocyanate to all or part of the hydroxyl groups of a polyhydric alcohol such as trimethylolpropane; lysine diisocyanate, and the like.

Examples of the organic polyimine compound include: n, N ' -diphenylmethane-4, 4 ' -bis (1-aziridinecarboxamide), trimethylolpropane-tris- β -aziridinylpropionate, tetramethylolmethane-tris- β -aziridinylpropionate, N ' -toluene-2, 4-bis (1-aziridinecarboxamide) triethylenemelamine, and the like.

When an organic polyisocyanate compound is used as the crosslinking agent (F), a hydroxyl group-containing polymer is preferably used as the polymer component (a). When the crosslinking agent (F) has an isocyanate group and the polymer component (a) has a hydroxyl group, a crosslinked structure can be easily introduced into the thermosetting resin layer by the reaction of the crosslinking agent (F) with the polymer component (a).

The crosslinking agent (F) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be only 1. The crosslinking agent (F) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer may be two or more, and in the case of two or more, the combination and ratio thereof may be arbitrarily selected.

When the crosslinking agent (F) is used, the content of the crosslinking agent (F) in the resin layer-forming composition (III-1) is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass, relative to 100 parts by mass of the content of the polymer component (A). By setting the content of the crosslinking agent (F) to the lower limit or more, the effect of using the crosslinking agent (F) can be more remarkably obtained. Further, by setting the content of the crosslinking agent (F) to the upper limit or less, the excessive use of the crosslinking agent (F) can be suppressed.

[ energy ray-curable resin (G) ]

The resin layer-forming composition (III-1) may contain an energy ray-curable resin (G). The thermosetting resin layer contains the energy ray-curable resin (G), and thus the properties can be changed by irradiation with energy rays.

The energy ray-curable resin (G) is a resin obtained by polymerizing (curing) an energy ray-curable compound.

Examples of the energy ray-curable compound include: the compound having at least 1 polymerizable double bond in the molecule is preferably an acrylate compound having a (meth) acryloyl group.

Examples of the acrylic ester compounds include: (meth) acrylates having a chain-like aliphatic skeleton such as trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1, 4-butanediol di (meth) acrylate, and 1, 6-hexanediol di (meth) acrylate; a (meth) acrylate having a cyclic aliphatic skeleton such as dicyclopentyl di (meth) acrylate; polyalkylene glycol (meth) acrylates such as polyethylene glycol di (meth) acrylate; an oligoester (meth) acrylate; a urethane (meth) acrylate oligomer; epoxy-modified (meth) acrylates; polyether (meth) acrylates other than the polyalkylene glycol (meth) acrylates; itaconic acid oligomers, and the like.

The weight average molecular weight of the energy ray-curable compound is preferably 100 to 30000, more preferably 300 to 10000.

The energy ray-curable compound used for polymerization may be only one kind, or two or more kinds. When two or more of the energy ray-curable compounds are used for the polymerization, the combination and ratio thereof can be arbitrarily selected.

The energy ray-curable resin (G) contained in the resin layer-forming composition (III-1) may be only one type, or two or more types. When the number of the energy ray-curable resins (G) contained in the resin layer-forming composition (III-1) is two or more, the combination and ratio thereof can be arbitrarily selected.

In the resin layer forming composition (III-1), the content of the energy ray-curable resin (G) is preferably 1 to 95% by mass, more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass, based on the total mass of the resin layer forming composition (III-1).

[ photopolymerization initiator (H) ]

When the resin layer-forming composition (III-1) contains the energy ray-curable resin (G), a photopolymerization initiator (H) may be contained in order to efficiently progress the polymerization reaction of the energy ray-curable resin (G).

As the above photopolymerization initiator (H) in the resin layer-forming composition (III-1), those same as those in the adhesive composition (I-1) of the No. 1 can be exemplified.

The photopolymerization initiator (H) contained in the resin layer-forming composition (III-1) may be only one kind, or two or more kinds. When the number of photopolymerization initiators (H) contained in the resin layer-forming composition (III-1) is two or more, the combination and ratio thereof can be arbitrarily selected.

In the resin layer-forming composition (III-1), the content of the photopolymerization initiator (H) is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 2 to 5 parts by mass, relative to 100 parts by mass of the energy ray-curable resin (G).

General additive (I)

The resin layer-forming composition (III-1) and the thermosetting resin layer may contain the general-purpose additive (I) within a range not to impair the effects of the present invention.

The general-purpose additive (I) may be any known additive, and may be arbitrarily selected depending on the purpose, and is not particularly limited, and preferable additives include, for example: plasticizers, antistatic agents, antioxidants, colorants (dyes, pigments), getters, and the like.

The resin layer-forming composition (III-1) and the thermosetting resin layer may contain only one kind of the general-purpose additive (I), or two or more kinds thereof. When the number of the general-purpose additives (I) contained in the resin layer-forming composition (III-1) and the thermosetting resin layer is two or more, the combination and ratio thereof can be arbitrarily selected.

The contents of the resin layer-forming composition (III-1) and the general-purpose additive (I) for the thermosetting resin layer are not particularly limited, and may be appropriately selected according to the purpose.

[ solvent ]

The resin layer-forming composition (III-1) preferably further contains a solvent. The composition (III-1) for forming a resin layer containing a solvent is excellent in handling properties.

The solvent is not particularly limited, and preferable solvents include, for example: hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropane-1-ol), and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone.

The solvent contained in the resin layer-forming composition (III-1) may be one kind or two or more kinds. When the number of solvents contained in the resin layer-forming composition (III-1) is two or more, the combination and ratio thereof can be arbitrarily selected.

The solvent contained in the resin layer-forming composition (III-1) is preferably methyl ethyl ketone or the like, from the viewpoint of enabling the components contained in the resin layer-forming composition (III-1) to be mixed more uniformly.

< method for producing composition for Forming thermosetting resin layer >)

The thermosetting resin layer-forming composition such as the resin layer-forming composition (III-1) can be obtained by blending the respective components for constituting the composition.

The order of addition of the components is not particularly limited, and two or more components may be added simultaneously.

When a solvent is used, the solvent may be mixed with any compounding ingredient other than the solvent to dilute the compounding ingredient in advance and then used, or the solvent may be mixed with any compounding ingredient other than the solvent without diluting the compounding ingredient in advance and used.

The method of mixing the components at the time of blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer, a paddle, or the like, a method of mixing using a mixer, and a method of mixing by applying ultrasonic waves.

The temperature and time at the time of addition and mixing of each component are not particularly limited as long as each component is not deteriorated, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ℃.

Manufacturing method of protective film forming sheet

The protective film-forming sheet can be produced by sequentially laminating the above layers so that the layers are in a corresponding positional relationship. The method of forming each layer is as described above.

For example, in the case where the 1 st adhesive layer or the 1 st intermediate layer is laminated on the 1 st substrate in the production of the 1 st support sheet, the 1 st adhesive layer or the 1 st intermediate layer may be laminated by applying the 1 st adhesive composition or the 1 st intermediate layer-forming composition described above on the 1 st substrate and drying or irradiating energy rays as necessary.

On the other hand, for example, in the case where a thermosetting resin layer is further laminated on the 1 st adhesive layer already laminated on the 1 st substrate, the thermosetting resin layer may be directly formed by applying the composition for forming a thermosetting resin layer on the 1 st adhesive layer. Similarly, in the case where the 1 st adhesive layer is further laminated on the 1 st intermediate layer already laminated on the 1 st substrate, the 1 st adhesive layer may be directly formed by applying the 1 st adhesive composition on the 1 st intermediate layer. In the case where a laminate structure of two continuous layers is formed using an arbitrary composition as described above, a layer formed of the composition may be further coated to newly form a layer. Among these, it is preferable to form a laminated structure of two continuous layers by forming a later laminated layer of the two layers on another release film in advance using the composition and bonding an exposed surface of the formed layer on the opposite side to the side in contact with the release film to an exposed surface of the remaining layer formed. In this case, the composition is preferably applied to the release-treated surface of the release film. The release film may be removed as needed after the formation of the laminated structure.

For example, in the case of producing a protective film-forming sheet in which a 1 st pressure-sensitive adhesive layer is laminated on a 1 st base and a thermosetting resin layer is laminated on the 1 st pressure-sensitive adhesive layer (the 1 st support sheet is a protective film-forming sheet in which a 1 st base and a 1 st pressure-sensitive adhesive layer are laminated), the 1 st pressure-sensitive adhesive layer is laminated on the 1 st base in advance by applying a 1 st pressure-sensitive adhesive composition to the 1 st base and drying it as necessary, a thermosetting resin layer is formed on a release film in advance by applying a thermosetting resin layer-forming composition separately to the release film and drying it as necessary, the exposed surface of the thermosetting resin layer is bonded to the exposed surface of the 1 st pressure-sensitive adhesive layer laminated on the 1 st base, and the thermosetting resin layer is laminated on the 1 st pressure-sensitive adhesive layer, whereby the protective film-forming sheet can be obtained.

For example, in the case of manufacturing a 1 st support sheet in which a 1 st intermediate layer is laminated on a 1 st base material and a 1 st pressure-sensitive adhesive layer is laminated on the 1 st intermediate layer, the 1 st intermediate layer is laminated on the 1 st base material in advance by applying a 1 st intermediate layer-forming composition to the 1 st base material and drying or irradiating energy rays as necessary, the 1 st adhesive layer is formed on a release film in advance by applying a 1 st pressure-sensitive adhesive composition separately to the release film and drying as necessary, the 1 st pressure-sensitive adhesive layer is laminated on the 1 st intermediate layer laminated on the 1 st base material, and the 1 st pressure-sensitive adhesive layer is laminated on the 1 st intermediate layer, whereby the 1 st support sheet can be obtained. In this case, for example, a thermosetting resin layer is formed on the release film in advance by applying a thermosetting resin layer-forming composition to the release film in advance and drying the composition as needed, the exposed surface of the thermosetting resin layer is bonded to the exposed surface of the 1 st adhesive layer laminated on the 1 st intermediate layer, and the thermosetting resin layer is laminated on the 1 st adhesive layer, whereby a protective film-forming sheet can be obtained.

In the case where the 1 st pressure-sensitive adhesive layer or the 1 st intermediate layer is to be laminated on the 1 st substrate, as described above, instead of the method of applying the 1 st pressure-sensitive adhesive composition or the 1 st intermediate layer-forming composition on the 1 st substrate, the 1 st pressure-sensitive adhesive layer or the 1 st intermediate layer-forming composition may be previously formed on a release film by applying the 1 st pressure-sensitive adhesive composition or the 1 st intermediate layer-forming composition on the release film and, if necessary, drying or irradiating energy rays thereto, and the 1 st pressure-sensitive adhesive layer or the 1 st intermediate layer may be laminated on the 1 st substrate by bonding the exposed surface of these layers to one surface of the 1 st substrate.

In any method, the release film may be removed at any point in time after the formation of the target laminated structure.

In this way, since layers other than the 1 st base material constituting the protective film forming sheet can be laminated by a method of forming the layers on the release film in advance and bonding the layers to the surface of the target layer, the protective film forming sheet can be produced by appropriately selecting the layers to be used in such steps as required.

The protective film-forming sheet is usually stored in a state where a release film is bonded to the surface of the outermost layer (for example, a thermosetting resin layer) on the side opposite to the 1 st support sheet. Therefore, the protective film-forming sheet can also be obtained by applying a composition for forming the outermost layer, such as a thermosetting resin layer-forming composition, to the release film (preferably the release-treated surface thereof) and drying the composition as necessary to form the outermost layer on the release film in advance, laminating the remaining layers on the exposed surface of the layer on the opposite side to the side in contact with the release film by any of the methods described above, and forming the layers in a state of being bonded without removing the release film.

Examples

The present invention will be described in detail below with reference to specific examples. However, the present invention is not limited to the following examples.

The components used for producing the composition for forming a thermosetting resin layer are as follows.

Polymeric component

Polymer component (A) -1: an acrylic resin (weight-average molecular weight 800000, glass transition temperature-28 ℃) obtained by copolymerizing butyl acrylate (hereinafter abbreviated as "BA") (55 parts by mass), methyl acrylate (hereinafter abbreviated as "MA") (10 parts by mass), glycidyl methacrylate (hereinafter abbreviated as "GMA") (20 parts by mass), and 2-hydroxyethyl acrylate (hereinafter abbreviated as "HEA") (15 parts by mass).

Epoxy resins

Epoxy resin (B1) -1: liquid bisphenol F type epoxy resin (product of Mitsubishi chemical corporation, "YL 983U")

Epoxy resin (B1) -2: polyfunctional aromatic epoxy resin ("EPPN-502H" manufactured by Nippon Kabushiki Kaisha)

Epoxy resin (B1) -3: dicyclopentadiene type epoxy resin ("EPICLON HP-7200" manufactured by DIC)

Thermal curing agent

Thermal curing agent (B2) -1: novolac type phenol resin (BRG-556, product of Showa Denko K.K.)

Curing accelerators

Curing accelerator (C) -1: 2-phenyl-4, 5-dihydroxymethylimidazole (Curezol 2PHZ-PW, manufactured by Shikoku Kogyo Co., Ltd.)

Filling materials

Filler (D) -1: epoxy-modified spherical silica (Adamanhs "Adamano YA 050C-MKK")

Production example 1

(production of adhesive resin (I-2 a))

2-ethylhexyl acrylate (hereinafter abbreviated as "2 EHA") (80 parts by mass) and HEA (20 parts by mass) were polymerized as raw materials of the copolymer to obtain an acrylic polymer.

To the acrylic polymer was added 2-methacryloyloxyethyl isocyanate (hereinafter abbreviated as "MOI") (22 parts by mass, about 80 mol% based on HEA) and subjected to addition reaction at 50 ℃ for 48 hours in an air stream, thereby obtaining the objective adhesive resin (I-2 a).

Production example 2

(production of adhesive resin (I-2 a))

An acrylic polymer was obtained by polymerizing butyl acrylate (hereinafter abbreviated as "BA") (52 parts by mass), methyl methacrylate (hereinafter abbreviated as "MMA") (20 parts by mass), and HEA (28 parts by mass) as raw materials of a copolymer.

To the acrylic polymer was added 2-methacryloyloxyethyl isocyanate (hereinafter abbreviated as "MOI") (28 parts by mass, about 90 mol% based on HEA) and subjected to addition reaction at 50 ℃ for 48 hours in an air stream, thereby obtaining the objective adhesive resin (I-2 a).

Production example 3

(production of adhesive resin (I-2 a))

Lauryl acrylate (hereinafter abbreviated as "LA") (80 parts by mass) and HEA (20 parts by mass) were polymerized as raw materials of the copolymer to obtain an acrylic polymer.

To this acrylic polymer, MOI was added so that the total number of moles of isocyanate groups in the MOI was 0.8 times the total number of moles of hydroxyl groups in the HEA, and an addition reaction was performed in an air stream at 50 ℃ for 48 hours, thereby obtaining the objective adhesive resin (I-2 a).

Production example 4

(production of adhesive resin (I-2 a))

An acrylic polymer was obtained by polymerizing 2EHA (40 parts by mass), vinyl acetate (hereinafter sometimes abbreviated as "Vac") (40 parts by mass), and HEA (20 parts by mass) as raw materials of a copolymer.

To this acrylic polymer, MOI was added so that the total number of moles of isocyanate groups in the MOI was 0.8 times the total number of moles of hydroxyl groups in the HEA, and an addition reaction was performed in an air stream at 50 ℃ for 48 hours, thereby obtaining the objective adhesive resin (I-2 a).

Production example 5

(production of adhesive resin (I-2 a))

An acrylic polymer was obtained by performing a polymerization reaction using 2EHA (80 parts by mass) and HEA (20 parts by mass) as raw materials of the copolymer.

To this acrylic polymer, MOI was added so that the total number of moles of isocyanate groups in the MOI was 0.8 times the total number of moles of hydroxyl groups in the HEA, and an addition reaction was performed in an air stream at 50 ℃ for 48 hours, thereby obtaining the objective adhesive resin (I-2 a).

[ example 1]

< production of protective film-forming sheet >

(production of composition for Forming thermosetting resin layer)

The polymer component (a) -1(100 parts by mass), the epoxy resin (B1) -1(135 parts by mass), the epoxy resin (B1) -2(90 parts by mass), the epoxy resin (B1) -3(150 parts by mass), the curing accelerator (C) -1(180 parts by mass), the curing accelerator (G) -1(1 part by mass), and the filler (D) -1(160 parts by mass) were dissolved in methyl ethyl ketone and stirred at 23 ℃.

(preparation of adhesive composition 1)

A tolylene diisocyanate trimer adduct of trimethylolpropane (Coronate L, manufactured by Tosoh Corona Co., Ltd.) (0.5 part by mass) was added as an isocyanate-based crosslinking agent to the pressure-sensitive adhesive resin (I-2a) (100 parts by mass) obtained in production example 1, and the mixture was stirred at 23 ℃ to obtain a 1 st pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the 1 st pressure-sensitive adhesive composition. The blending parts in "production of adhesive composition 1" are all solid content equivalent values.

(production of protective film Forming sheet)

The obtained 1 st pressure-sensitive adhesive composition was applied to the release-treated surface of a release film (SP-PET 381031, manufactured by Lindelco Ltd., thickness 38 μm) obtained by subjecting one surface of a polyethylene terephthalate film to a release treatment by a silicone treatment, and heated and dried at 110 ℃ for 1 minute, thereby forming a 1 st pressure-sensitive adhesive layer having a thickness of 30 μm on the release film.

Then, a laminated film having a thickness of 105 μm, in which a polyolefin film (thickness 25 μm), an adhesive layer (thickness 2.5 μm), a polyethylene terephthalate film (thickness 50 μm), an adhesive layer (thickness 2.5 μm) and a polyolefin film (thickness 25 μm) were laminated in this order as a 1 st base material, was laminated on the exposed surface of the 1 st pressure-sensitive adhesive layer, to obtain a 1 st supporting sheet.

The obtained composition for forming a thermosetting resin layer was applied to a release-treated surface of a release film (SP-PET 381031 manufactured by Lindelco Ltd., thickness 38 μm) obtained by subjecting one surface of a polyethylene terephthalate film to a release treatment by a silicone treatment, and dried at 100 ℃ for 2 minutes to prepare a thermosetting resin layer having a thickness of 40 μm.

Next, the release film was removed from the 1 st pressure-sensitive adhesive layer of the 1 st support sheet obtained above, and the exposed surface of the thermosetting resin layer obtained above was laminated on the exposed surface of the 1 st pressure-sensitive adhesive layer, to obtain a protective film-forming sheet in which the 1 st base material, the 1 st pressure-sensitive adhesive layer, the thermosetting resin layer, and the release film were laminated in this order in the thickness direction thereof.

Comparative example 1

(preparation of adhesive composition 1)

To 100 parts by mass of the adhesive resin (I-2a) obtained in production example 2 was added 1.0 part by mass of a tolylene diisocyanate trimer adduct of trimethylolpropane (Coronate L, manufactured by tokyo co., ltd.) as an isocyanate-based crosslinking agent, and the mixture was stirred at 23 ℃. The blending parts in "production of adhesive composition 1" are all solid content equivalent values.

(production of protective film Forming sheet)

A 1 st support sheet was obtained in the same manner as in example 1, except that the 1 st adhesive composition described in example 1 was changed to the 1 st adhesive composition of comparative example 1 obtained above.

The obtained composition for forming a thermosetting resin layer was applied to the release-treated surface of a release film (SP-PET 381031 manufactured by Lindelco Ltd., thickness 38 μm) obtained by subjecting one surface of a polyethylene terephthalate film to a release treatment by a silicone treatment, and dried by heating at 100 ℃ for 2 minutes to prepare a thermosetting resin layer having a thickness of 40 μm.

Next, the release film was removed from the 1 st pressure-sensitive adhesive layer of the 1 st supporting sheet obtained above, and the exposed surface of the thermosetting resin layer similar to that of the example 1 obtained above was laminated on the exposed surface of the 1 st pressure-sensitive adhesive layer, to obtain a protective film-forming sheet of comparative example 1 in which the 1 st base material, the 1 st pressure-sensitive adhesive layer, the thermosetting resin layer, and the release film were laminated in this order in the thickness direction thereof.

[ example 2]

(preparation of adhesive composition 1)

A tolylene diisocyanate trimer adduct of trimethylolpropane (Coronate L, manufactured by Tosoh Corona Co., Ltd.) (1.0 part by mass) was added as an isocyanate-based crosslinking agent to the pressure-sensitive adhesive resin (I-2a) (100 parts by mass) obtained in production example 3, and the mixture was stirred at 23 ℃ to obtain a 1 st pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the 1 st pressure-sensitive adhesive composition. The blending parts in "production of adhesive composition 1" are all solid content equivalent values.

(production of protective film Forming sheet)

A protective film-forming sheet of example 2 was obtained in the same manner as in example 1, except that the adhesive composition of example 1 was changed to the adhesive composition of example 2 obtained as described above, instead of the adhesive composition of example 1.

[ example 3]

(preparation of adhesive composition 1)

A tolylene diisocyanate trimer adduct of trimethylolpropane (Coronate L, manufactured by Tosoh Corona Co., Ltd.) (1.0 part by mass) was added as an isocyanate-based crosslinking agent to the pressure-sensitive adhesive resin (I-2a) (100 parts by mass) obtained in production example 4, and the mixture was stirred at 23 ℃ to obtain a 1 st pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the 1 st pressure-sensitive adhesive composition. The blending parts in "production of adhesive composition 1" are all solid content equivalent values.

(production of protective film Forming sheet)

A protective film-forming sheet of example 3 was obtained in the same manner as in example 1, except that the adhesive composition of example 1 was changed to the adhesive composition of example 3 obtained as described above, instead of the adhesive composition of example 1.

[ example 4]

(preparation of adhesive composition 1)

A tolylene diisocyanate trimer adduct of trimethylolpropane (Coronate L, manufactured by Tosoh Corona Co., Ltd.) (1.0 part by mass) was added as an isocyanate-based crosslinking agent to the pressure-sensitive adhesive resin (I-2a) (100 parts by mass) obtained in production example 5, and the mixture was stirred at 23 ℃ to obtain a 1 st pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the 1 st pressure-sensitive adhesive composition. The blending parts in "production of adhesive composition 1" are all solid content equivalent values.

(production of protective film Forming sheet)

A protective film-forming sheet of example 4 was obtained in the same manner as in example 1, except that the adhesive composition of example 1 was changed to the adhesive composition of example 4 obtained as described above, instead of the adhesive composition of example 1.

< evaluation of protective film-Forming sheet >

The thermosetting resin layers and the 1 st adhesive layer obtained in example 1 and comparative example 1 were subjected to contact angle determination of pure water, diiodomethane and 1-bromonaphthalene at a temperature of 23 ℃ and a humidity of 50%, to thereby determine the dispersion force component γ_s ^dPolar component gamma_s ^pHydrogen bond component gamma_s ^hThe surface free energy of each layer surface is determined from the sum of the surface free energies of each layer surface_s ^total。

The results are shown in Table 1.

γ of thermosetting resin layer of each protective film-forming sheet of example 1 and comparative example 1_s ^totalGamma with 1 st adhesive layer_s ^totalThe difference is shown in table 1.

The difference between the contact angle of the thermosetting resin layer with respect to water and the contact angle of the 1 st pressure-sensitive adhesive layer with respect to water in each of the protective film-forming sheets of example 1 and comparative example 1 is shown in table 1.

Using a UV irradiation apparatus (RAD-2000 m/8, manufactured by Lindco corporation), the illuminance was 230mW/cm²The quantity of light was 760mJ/cm²The 1 st pressure-sensitive adhesive layers obtained in examples 1 to 4 and comparative example 1 were irradiated with UV under the conditions of (1), and then contact angles of pure water, diiodomethane and 1-bromonaphthalene were determined in an environment of 23 ℃ and a humidity of 50%, to thereby determine the dispersion force component γ_s ^dPolar component gamma_s ^pHydrogen bond component gamma_s ^hThe surface free energy of each layer surface is determined from the sum of the surface free energies of each layer surface_s ^total。

The results are shown in table 2 together with the results of the uncured thermosetting resin layer.

γ of thermosetting resin layer of each protective film-forming sheet of example 1 and comparative example 1_s ^totalGamma with 1 st adhesive layer after UV curing_s ^totalThe difference is shown in table 2.

The difference between the contact angle of the thermosetting resin layer of each protective film-forming sheet of example 1 and comparative example 1 with water and the contact angle of the 1 st pressure-sensitive adhesive layer after UV curing with water is shown in table 2.

< evaluation of Release Property after UV curing >

After preparing the protective film-forming sheets of examples 1 to 4 and comparative example 1 for 1 week, the releasability after UV curing was evaluated according to the following procedure.

A protective film forming sheet was attached to the circuit surface of a 6-inch semiconductor wafer with bumps by thermal lamination at 70 ℃.

After the temperature was returned to room temperature after the application (about 5 minutes later), the resultant was irradiated with UV light at an illuminance of 230mW/cm using a UV irradiation apparatus (RAD-2000 m/8, manufactured by Lindceko Co., Ltd.)²The quantity of light was 760mJ/cm²Under the conditions of (1), UV is irradiated to cure the 1 st adhesive layer. Then, when the 1 st support sheet is to be peeled from the thermosetting resin layer, in the case of the protective film-forming sheets of examples 1 to 4, the 1 st support sheet formed of the 1 st base material and the 1 st pressure-sensitive adhesive layer can be easily peeled off at the interface with the thermosetting resin layer (peelability "good"), but in the case of the protective film-forming sheet of comparative example 1, the 1 st base material is peeled off in a state of being bonded to the thermosetting resin layer, or the 1 st pressure-sensitive adhesive layer is locally aggregated and broken to remain on the surface of the thermosetting resin layer (peelability "poor").

Despite the gamma of the thermosetting resin layer_s ^totalGamma with 1 st adhesive layer after UV curing_s ^totalThe difference between the contact angle of the thermosetting resin layer with water and the contact angle of the 1 st adhesive layer after UV curing with water were not greatly different as shown in table 2, but showed a large difference in releasability between the 1 st support sheet and the thermosetting resin layer. That is, γ of the thermosetting resin layer not after the UV curing but before the UV curing_s ^totalGamma with 1 st adhesive layer_s ^totalThe difference between the contact angles of the thermosetting resin layer before UV curing and the 1 st adhesive layer with water has a great influence on the releasability between the 1 st support sheet and the thermosetting resin layer.

The protective film-forming sheets of examples 1 to 4 and comparative example 1 used the polymer component (a) -1 containing Butyl Acrylate (BA) as a main component in the thermosetting resin layer, and as a result, the adhesive resin (I-2a) containing 2-ethylhexyl acrylate (2EHA) or Lauryl Acrylate (LA) as a main component was used in the 1 st adhesive layer of examples 1 to 4, and therefore the surface free energy could be made as described aboveThe difference is 10mJ/m²In contrast, in comparative example 1, the adhesive resin (I-2a) containing Butyl Acrylate (BA) as a main component, which is the same as that of the thermosetting resin layer, was used in the 1 st adhesive layer, and therefore the difference in surface free energy was small.

It takes about 1 week to produce a protective film-forming sheet until the quality such as adhesive force is stabilized. Therefore, it is considered that the protective film-forming sheet of comparative example 1, in which the difference between the surface free energy of the thermosetting resin layer and the surface free energy of the 1 st supporting sheet is small, causes component transfer at the interface between the both, and abnormally increases the adhesive force, resulting in peeling failure.

It is considered that the protective film-forming sheet of example 1 having a large difference between the surface free energy of the thermosetting resin layer and the surface free energy of the 1 st support sheet did not cause component transfer at the interface between the two, and the adhesion was stable, and the easy-peeling property at the interface between the 1 st support sheet and the thermosetting resin layer was excellent.

Industrial applicability

The present invention can be used for manufacturing a semiconductor chip or the like having bumps at connection pad portions used in a flip chip mounting method.

Claims (3)

1. A protective film-forming sheet comprising a 1 st support sheet and a thermosetting resin layer laminated thereon,

the thermosetting resin layer is a layer for being stuck on a surface having bumps of a semiconductor wafer and forming a protective film on the surface by thermosetting,

the difference between the surface free energy of the 1 st support sheet side surface of the thermosetting resin layer before thermosetting and the surface free energy of the thermosetting resin layer side surface of the 1 st support sheet is 10mJ/m²In the above-mentioned manner,

the difference between the contact angle of the surface of the first support sheet side of the thermosetting resin layer before thermosetting with water and the contact angle of the surface of the first support sheet side of the thermosetting resin layer with water is 30 ° or more.

2. The protective film-forming sheet according to claim 1, wherein a thermosetting resin layer is laminated on a 1 st adhesive layer of a 1 st support sheet, and the 1 st support sheet is formed by laminating the 1 st adhesive layer on a 1 st base material,

the difference between the surface free energy of the 1 st support sheet side surface of the thermosetting resin layer before thermal curing and the surface free energy of the thermosetting resin layer side surface of the 1 st adhesive layer was 10mJ/m²In the above-mentioned manner,

the difference between the contact angle of the 1 st support sheet side surface of the thermosetting resin layer with water before thermosetting and the contact angle of the 1 st adhesive layer side surface with water is 30 ° or more.

3. The protective film-forming sheet according to claim 1, which is a protective film-forming sheet obtained by laminating a thermosetting resin layer on a 1 st adhesive layer of a 1 st support sheet, wherein the 1 st support sheet is a sheet obtained by laminating a 1 st intermediate layer on a 1 st base material and laminating the 1 st adhesive layer on the 1 st intermediate layer,

the difference between the surface free energy of the 1 st support sheet side surface of the thermosetting resin layer before thermal curing and the surface free energy of the thermosetting resin layer side surface of the 1 st adhesive layer was 10mJ/m²In the above-mentioned manner,

the difference between the contact angle of the 1 st support sheet side surface of the thermosetting resin layer with water before thermosetting and the contact angle of the 1 st adhesive layer side surface with water is 30 ° or more.

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