JP6775517B2 - Protective film forming sheet - Google Patents

Description

The present invention relates to a protective film forming sheet.
The present application claims priority based on Japanese Patent Application No. 2015-217115 filed in Japan on November 4, 2015, the contents of which are incorporated herein by reference.

Conventionally, when a multi-pin LSI package used for MPU, gate array, etc. is mounted on a printed wiring board, a convex electrode (bump) made of eutectic solder, high temperature solder, gold, etc. is attached to the connection pad as a semiconductor chip. ) Has been formed, and a flip chip mounting method has been adopted in which these bumps are brought into face-to-face contact with the corresponding terminal portions on the chip mounting substrate and melted / diffused bonded by a so-called face-down method. ..

The semiconductor chip used in this mounting method can be obtained, for example, by grinding or dicing the surface of a semiconductor wafer having bumps formed on the circuit surface on the side opposite to the circuit surface to individualize it. In the process of obtaining such a semiconductor chip, usually, for the purpose of protecting the circuit surface and bumps of the semiconductor wafer, a curable resin film laminated on the support sheet is attached to the bump forming surface, and this film is cured. A protective film is formed on the bump forming surface.

As such a curable resin film, a film containing a thermosetting component that is cured by heating is widely used, and as a protective film forming sheet provided with such a thermosetting resin layer, the film is used. A thermoplastic resin layer having a specific thermosetting rate is laminated on the surface of the film, and a non-plastic thermoplastic resin layer at 25 ° C. is laminated on the uppermost layer of the thermoplastic resin layer (1). See Patent Document 1). According to Patent Document 1, this protective film forming sheet is excellent in bump filling property, wafer processability, electrical connection reliability after resin sealing, and the like.

Japanese Unexamined Patent Publication No. 2005-028734

However, when an attempt is made to form a protective film on the bump forming surface by using a conventional protective film forming sheet in which a thermosetting resin layer is laminated on the support sheet, when the support sheet is peeled off, It does not peel off well at the interface between the support sheet and the thermosetting resin layer, if you try to peel it off forcibly, it will peel off at the interface inside the support sheet such as the base material / adhesive layer, or the adhesive will adhere to the protective film side. Many peeling defects may be observed.

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

The present invention is a protective film forming sheet in which a thermosetting resin layer is laminated on a first support sheet, and the thermosetting resin layer is attached to a surface of a semiconductor wafer having bumps and heat is applied. It is a layer for forming a protective film on the surface by curing, and the surface free energy of the thermosetting resin layer on the side surface of the first support sheet before thermosetting and the surface free energy of the first support sheet. This is a protective film forming sheet characterized in that the difference from the surface free energy of the surface on the thermosetting resin layer side is 10 mJ / m ² or more.
In the protective film forming sheet, the contact angle of the surface of the thermosetting resin layer on the side of the first support sheet with water before heat curing and the contact of the surface of the first support sheet with water on the surface of the thermosetting resin layer with water. The difference from the angle is preferably 30 ° or more.

The protective film forming sheet of the present invention has excellent peelability at the interface between the first support sheet and the thermosetting resin layer.

It is sectional drawing which shows typically one Embodiment of the protective film forming sheet of this invention. It is sectional drawing which shows typically the other embodiment of the protective film forming sheet of this invention. It is sectional drawing which shows still the other embodiment of the protective film formation sheet of this invention schematically. It is sectional drawing which shows typically an example of the semiconductor wafer which has a bump. It is sectional drawing which shows typically the state that the sheet for forming a protective film of this invention was attached to the surface which has the bump of the semiconductor wafer. It is sectional drawing which shows typically an example of the semiconductor wafer provided with the protective film formed by using the protective film forming sheet of this invention.

The present invention is a protective film forming sheet in which a thermosetting resin layer is laminated on a first support sheet, and the thermosetting resin layer is attached to a surface of a semiconductor wafer having bumps and heat is applied. It is a layer for forming a protective film on the surface by curing, and the surface free energy of the thermosetting resin layer on the side surface of the first support sheet before thermosetting and the surface free energy of the first support sheet. This is a protective film forming sheet characterized in that the difference from the surface free energy of the surface on the thermosetting resin layer side is 10 mJ / m ² or more.

The surface free energy γ _s ^total of each solid is the surface free energy γ _L ^d of the dispersive force component, the surface free energy γ _L ^{p of} the polar component, and the surface free energy γ _L ^h of the hydrogen bond component. By measuring the contact angles of the solid surfaces of known liquids such as pure water, diiodomethane, and 1-bromonaphthalene, the surface free energy γ _s ^d and polarity of the dispersive force component can be obtained with respect to the following formula (2). surface free energy gamma _{s p} ^components, and solving simultaneous equations relating to surface free energy gamma _s ^h of hydrogen bonding component can be obtained by substituting the following equation (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 attached to a surface of a semiconductor wafer having bumps via its thermosetting resin layer. Then, the thermosetting resin layer after sticking increases in fluidity by heating, spreads between the bumps so as to cover the bumps, and adheres to the circuit surface, and at the same time, the surface of the bumps, particularly the portion near the circuit surface. Cover the surface and embed bumps. The thermosetting resin layer in this state is further thermally cured by heating to finally form a first protective film, and protects the bumps on the circuit surface in a state of being in close contact with the surface thereof.
For example, in the semiconductor wafer to which the protective film forming sheet is attached, the surface opposite to the circuit surface is ground, the first support sheet is removed, and then the thermosetting resin layer is heated. The bumps are embedded and the first protective film is formed, and finally, the first protective film is incorporated into the semiconductor device with the first protective film.

In the protective film forming sheet of the present invention, the surface free energy of the surface of the thermosetting resin layer on the side of the first support sheet before heat curing and the surface of the surface of the first support sheet on the side of the thermosetting resin layer. Since the difference from the surface free energy is 10 mJ / m ² or more, there is no migration of components at the interface between the two, and when the first support sheet is removed, the interface between the first support sheet and the thermosetting resin layer Has excellent peelability. The difference between the surface free energy of the thermosetting resin layer on the surface of the first support sheet side before heat curing and the surface free energy of the surface of the first support sheet on the surface of the thermosetting resin layer is 12 to 100 mJ. preferably / a ^{m 2,} more preferably a 15~90mJ / ^{m 2,} is preferably 18~85mJ / ^{m 2,} and particularly preferably 20~80mJ / ^{m 2.}

Further, there is a difference between the contact angle of the thermosetting resin layer on the surface of the first support sheet side with water before heat curing and the contact angle of the surface of the first support sheet on the surface of the thermosetting resin layer with water. When the temperature is 30 ° or more, the easy peelability of the interface between the first support sheet and the thermosetting resin layer becomes more excellent when the first support sheet is removed.

In the protective film forming sheet of the present invention, the surface of the first support sheet on the thermosetting resin layer side may be composed of an energy ray-curable pressure-sensitive adhesive or a non-energy ray-curable pressure-sensitive adhesive, but energy. In the case of a ray-curable pressure-sensitive adhesive, when the value of the difference in surface free energy before energy ray curing is within the above range, there is no transfer of components at the interface between the two before energy ray curing, and the second after energy ray curing. 1 Even when the support sheet is removed, the interface between the first support sheet and the thermosetting resin layer is easily peeled off. Even if the value of the difference in surface free energy after energy ray curing deviates from the above range, it has little effect on the transfer of components at the interface between the two before energy ray curing, and when the first support sheet is removed. However, there is little effect on the easy peelability of the interface between the first support sheet and the thermosetting resin layer.

Hereinafter, the protective film forming sheet according to the present invention will be described in detail with reference to the drawings.
In addition, the drawings used in the following description may be shown differently from the actual protective film forming sheet for convenience in order to make the features easy to understand. In addition, the materials, conditions, etc. exemplified in the following description are examples, and the present invention is not necessarily limited to them, and the present invention can be appropriately modified without changing the gist thereof. ..

(1) First Support Sheet The first support sheet may be composed of one layer (single layer) or may be composed of two or more layers. When the support sheet is composed of a plurality of layers, the constituent materials and the 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 addition, in this specification, not only in the case of the 1st support sheet, "a plurality of layers may be the same or different from each other" means "all layers may be the same, or all layers". May be different, and only some of the layers may be the same. ”Furthermore,“ a plurality of layers are different from each other ”means that“ at least one of the constituent materials and the thickness of each layer is different from each other. It means that.

Preferred first support sheets include, for example, one in which a first pressure-sensitive adhesive layer is laminated on a first base material, a first intermediate layer is laminated on a first base material, and a first intermediate layer is laminated on the first intermediate layer. Examples thereof include those in which one pressure-sensitive adhesive layer is laminated and those in which only the first base material is used.

An example of the protective film forming sheet of the present invention will be described below for each type of the first support sheet with reference to the drawings.

FIG. 1 is a cross-sectional view schematically showing an embodiment of the protective film forming sheet of the present invention. The protective film forming sheet 1 shown here is a first support sheet 101 in which the first pressure-sensitive adhesive layer 13 is laminated on the first base material. That is, the protective film forming sheet 1 is configured by providing the first pressure-sensitive adhesive layer 13 on the first base material 11 and the thermosetting resin layer 12 on the first pressure-sensitive adhesive layer 13. The first support sheet 101 is a laminate of the first base material 11 and the first pressure-sensitive adhesive layer 13, and is on one surface 101a of the first support sheet 101, that is, on one surface 13a of the first pressure-sensitive adhesive layer 13. Is provided with a thermosetting resin layer 12. In the protective film forming sheet 1, the surface free energy of the surface of the thermosetting resin layer 12 on the side of the first support sheet 101 before heat curing and the surface of the surface of the first adhesive layer 13 on the side of the thermosetting resin layer 12 are free. When the difference from the energy is 10 mJ / m ² or more, there is no transfer of components at the interface between the two, the adhesive force is stable, and the interface between the first support sheet 101 and the thermosetting resin layer 12 is easy. It has excellent peelability. The difference between the surface free energy of the surface of the thermosetting resin layer 12 on the first support sheet 101 side before heat curing and the surface free energy of the surface of the first adhesive layer 13 on the surface of the thermosetting resin layer 12 is 12 to 12 to it is preferably 100 mJ / ^{m 2,} more preferably from 15~90mJ / ^{m 2,} is preferably 18~85mJ / ^{m 2,} and particularly preferably 20~80mJ / ^{m 2.}

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 designated by the same reference numerals as those in FIG. 1, and detailed description thereof will be omitted. This also applies to the figures after FIG.
In the protective film forming sheet 2 shown here, the first intermediate layer 14 is laminated on the first base material 11 and the first adhesive layer 13 is laminated on the first intermediate layer 14 as the first support sheet 102. It is the one that is made. That is, the protective film forming sheet 2 has a first intermediate layer 14 on the first base material 11, a first pressure-sensitive adhesive layer 13 on the first intermediate layer 14, and is cured on the first pressure-sensitive adhesive layer 13. It is configured to include a sex resin layer 12. The first support sheet 102 is a laminate in which the first base material 11, the first intermediate layer 14, and the first pressure-sensitive adhesive layer 13 are laminated in this order, and is on one surface 102a of the first support sheet 102, that is, A thermosetting resin layer 12 is provided on one surface 13a of the first pressure-sensitive adhesive layer 13.
In other words, the protective film forming sheet 2 is the protective film forming sheet 1 shown in FIG. 1 in which the first intermediate layer 14 is further provided at the interface between the first base material 11 and the first pressure-sensitive adhesive layer 13. Is.
In the protective film forming sheet 2, the surface free energy of the surface of the thermosetting resin layer 12 on the side of the first support sheet 102 before heat curing and the surface of the surface of the first adhesive layer 13 on the side of the thermosetting resin layer 12 are free. When the difference from the energy is 10 mJ / m ² or more, there is no transfer of components at the interface between the two, the adhesive force is stable, and the interface between the first support sheet 102 and the thermosetting resin layer 12 is easy. It has excellent peelability. The difference between the surface free energy of the surface of the thermosetting resin layer 12 on the side of the first support sheet 102 before heat curing and the surface free energy of the surface of the first adhesive layer 13 on the surface of the thermosetting resin layer 12 is 12 to it is preferably 100 mJ / ^{m 2,} more preferably from 15~90mJ / ^{m 2,} is preferably 18~85mJ / ^{m 2,} and particularly preferably 20~80mJ / ^{m 2.}

FIG. 3 is a cross-sectional view schematically showing still another embodiment of the protective film forming sheet of the present invention.
The protective film forming sheet 3 shown here uses only the first base material 11 as the first support sheet 103. That is, the protective film forming sheet 3 is configured by providing the curable resin layer 12 on the first base material 11. The first support sheet 103 is composed of only the first base material 11, and the curable resin layer 12 is directly placed on one surface 103a of the first support sheet 103, that is, on one surface 11a of the first base material 11. It is provided in contact.
In other words, the protective film forming sheet 3 is formed by removing the first pressure-sensitive adhesive layer 13 from the protective film forming sheet 1 shown in FIG. In the protective film forming sheet 3, the surface free energy of the surface of the thermosetting resin layer 12 on the side of the first support sheet 103 before heat curing and the surface free energy of the surface of the first support sheet 103 on the side of the thermosetting resin layer 12 When the difference from the above is 10 mJ / m ² or more, there is no migration of components at the interface between the two, the adhesive strength is stable, and the interface between the first support sheet 103 and the thermosetting resin layer 12 is easily peeled off. It will be excellent in sex. The difference between the surface free energy of the surface of the thermosetting resin layer 12 on the first support sheet 103 side before heat curing and the surface free energy of the surface of the first support sheet 103 on the surface of the thermosetting resin layer 12 is 12 to 100 mJ. / preferably ^m is ^2, more preferably 15～90MJ / ^{m 2,.} 18 to
It is preferably 85 mJ / ^{m 2,} and particularly preferably 20~80mJ / ^{m 2.}

FIG. 4 is a cross-sectional view schematically showing an example of a semiconductor wafer 90 having bumps 91. A plurality of bumps 91 are provided on the circuit surface 90a of the semiconductor wafer 90 shown here.
The bump 91 has, for example, a shape in which a part of a sphere is cut off by a flat surface, and the flat surface corresponding to the cut and 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, but the effect of the present invention (easy peeling of the interface between the first support sheet and the thermosetting resin layer) is that the projection surface is spherical including an elliptical shape. Especially effective for bumps.

FIG. 5 is a cross-sectional view schematically showing a state in which the protective film forming sheet of the present invention is attached to the surface of the semiconductor wafer 90 having the bumps 91. The thermosetting resin layer 12 after sticking increases in fluidity by heating, spreads between the bumps so as to cover the bumps, adheres to the circuit surface, and is in close contact with the bump surface, particularly the surface of the portion near the circuit surface. Cover and embed 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 first adhesive layer 13 to be thicker than the height of the bump 91, the bump 91 Is entirely covered with the curable resin layer 12 and the first pressure-sensitive adhesive layer 13.

In the semiconductor wafer to which the protective film forming sheet is attached, for example, the surface opposite to the circuit surface is ground, the first support sheet 101 is removed, and then the thermosetting resin layer 12 is heated. The first protective film 12'is formed, and finally, the chip is cut into a predetermined size with the first protective film 12'attached and incorporated into the semiconductor device.

FIG. 6 is a cross-sectional view schematically showing an example of a semiconductor wafer 90 provided with a first protective film 12'formed by using the protective film forming sheet 1 of the present invention. The first protective film 12'is formed by using the thermosetting resin film of the present invention, covers the circuit surface 90a of the semiconductor wafer 90, and further covers the top of the bump 91 among the surfaces 91a of the bump 91. It covers areas other than 911 and its vicinity.

In the protective film forming sheet 1 of the present invention, the interface between the first support sheet 101 and the thermosetting resin layer 12 is easily peeled off, that is, the interface between the first pressure-sensitive adhesive layer 13 and the thermosetting resin layer 12 Since it is excellent in easy peeling property, when the first support sheet 101 is peeled off and removed, the thermosetting resin layer 12 becomes the first protective film 12'after curing without causing peeling failure, as shown in FIG. Can be left behind to protect the circuit surface and bumps.

○ First base material The first base material may be composed of one layer (single layer) or may be composed of two or more layers. When the base material is composed of a plurality of layers, the constituent materials and the 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, not only in the case of a base material, "a plurality of layers may be the same or different from each other" means "all layers may be the same or all layers are different". It means that only some of the layers may be the same, and that "plurality of layers are different from each other" means that "at least one of the constituent materials and thickness of each layer is different from each other". Means.

The first base material is in the form of a sheet or a film, and examples of the constituent material thereof 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); other than polyethylenes such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resin. Polyethylene; ethylene-based copolymers such as ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester copolymer, ethylene-norbornene copolymer (ethylene as monomer) (Copolymers obtained using); Vinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymers (resins obtained using vinyl chloride as the monomer); Polystyrene; Polycycloolefins; Polyethylene terephthalate, polyethylene Polymers such as naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalenedicarboxylate, all aromatic polyesters in which all constituent units have aromatic cyclic groups; co-polymers of two or more of the above polymers. Polymers; poly (meth) acrylic acid esters; polyurethanes; polyurethane acrylates; polyimides; polyamides; polycarbonates; fluororesins; polyacetals; modified polyphenylene oxides; polyphenylene sulfides; polysulfones; polyether ketones and the like.
Further, examples of the resin include polymer alloys such as a mixture of the polyester and other resins. The polymer alloy of the polyester and the resin other than the polyester preferably has a relatively small amount of the resin other than the polyester.
Further, as the resin, for example, a crosslinked resin obtained by cross-linking one or more of the resins exemplified above; modification of an ionomer or the like using one or more of the resins exemplified so far. Resin is also mentioned.

In addition, in this specification, "(meth) acrylic acid" is a concept including both "acrylic acid" and "methacrylic acid". The same applies to terms similar to (meth) acrylic acid, for example, "(meth) acrylate" is a concept that includes both "acrylate" and "methacrylate", and is a "(meth) acryloyl group". Is a concept that includes both an "acryloyl group" and a "methacryloyl group".

The resin constituting the first base material may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

The first base material may be only one layer (single layer), may be a plurality of layers of two or more layers, and when there are a plurality of layers, the plurality of layers may be the same or different from each other, and a combination of the plurality of layers may be used. Is not particularly limited.

The thickness of the first base material 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, the "thickness of the first base material" means the thickness of the entire first base material, and for example, the thickness of the first base material composed of a plurality of layers is all that constitute the first base material. Means the total thickness of the layers of.

The first base material preferably has a high thickness accuracy, that is, a material in which variation in thickness is suppressed regardless of the site. Among the above-mentioned constituent materials, as a material that can be used to construct a first base material having such a high accuracy of thickness, for example, polyethylene, polyolefin other than polyethylene, polyethylene terephthalate, ethylene-vinyl acetate co-weight. Coalescence and the like can be mentioned.

The first base material contains various known additives such as fillers, colorants, antistatic agents, antioxidants, organic lubricants, catalysts, and softeners (plasticizers) in addition to the main constituent materials such as the resin. You may be doing it.

The first base material may be transparent, opaque, colored depending on the purpose, or another layer may be vapor-deposited.
When the first pressure-sensitive adhesive layer or the curable resin layer, which will be described later, has energy ray curability, the first base material preferably transmits energy rays.

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

○ First Adhesive Layer The first adhesive layer is in the form of a sheet or a film and contains an adhesive.
Examples of the pressure-sensitive adhesive include an acrylic resin (a pressure-sensitive adhesive made of a resin having a (meth) acryloyl group), a urethane-based resin (a pressure-sensitive adhesive made of a resin having a urethane bond), and a rubber-based resin (a resin having a rubber structure). (Adhesive made of), silicone resin (adhesive made of resin having siloxane bond), epoxy resin (adhesive made of resin having epoxy group), polyvinyl ether, adhesive resin such as polycarbonate, etc. Based resin is preferable.

In the present invention, the "adhesive resin" is a concept including both a resin having adhesiveness and a resin having adhesiveness. For example, not only the resin itself has adhesiveness but also the resin itself has adhesiveness. It also includes a resin that exhibits adhesiveness when used in combination with other components such as additives, and a resin that exhibits adhesiveness due to the presence of a trigger such as heat or water.

The first pressure-sensitive adhesive layer may be only one layer (single layer), may be a plurality of layers of two or more layers, and when there are a plurality of layers, the plurality of layers may be the same as or different from each other, and the plurality of layers may be different. The combination is not particularly limited.

The thickness of the first pressure-sensitive adhesive layer is preferably 1 to 1000 μm, more preferably 5 to 500 μm, and particularly preferably 10 to 100 μm.
Here, the "thickness of the first pressure-sensitive adhesive layer" means the thickness of the entire first pressure-sensitive adhesive layer, and for example, the thickness of the first pressure-sensitive adhesive layer composed of a plurality of layers is the thickness of the first pressure-sensitive adhesive layer. It means the total thickness of all the layers that make up.

The first pressure-sensitive adhesive layer may be formed by using an energy ray-curable pressure-sensitive adhesive or may be formed by using a non-energy ray-curable pressure-sensitive adhesive. The first pressure-sensitive adhesive layer formed by using the energy ray-curable pressure-sensitive adhesive can easily adjust the physical properties before and after curing.
In the present invention, the "energy beam" means an electromagnetic wave or a charged particle beam having an energy quantum, and examples thereof include ultraviolet rays and electron beams.
Ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, a black light, an LED lamp, or the like as an ultraviolet source. The electron beam can be irradiated with an electron beam generated by an electron beam accelerator or the like.
In the present invention, "energy ray curable" means a property of being cured by irradiating with energy rays, and "non-energy ray curable" means a property of not being cured by irradiating with energy rays. ..

<< First Adhesive Composition >>
The first pressure-sensitive adhesive layer can be formed by using a first pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, the first pressure-sensitive adhesive layer can be formed on a target portion by applying the first pressure-sensitive adhesive composition to the surface to be formed of the first pressure-sensitive adhesive layer and drying it if necessary. A more specific method for forming the first pressure-sensitive adhesive layer will be described in detail later together with a method for forming the other layers. The ratio of the contents of the components that do not vaporize at room temperature in the first pressure-sensitive adhesive composition is usually the same as the ratio of the contents of the components in the first pressure-sensitive adhesive layer. In addition, in this specification, "normal temperature" means a temperature which is not particularly cooled or heated, that is, a normal temperature, and examples thereof include a temperature of 15 to 25 ° C.

The coating of the first pressure-sensitive adhesive composition may be carried out by a known method, for example, an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, a knife coater, and the like. Examples thereof include a method using various coaters such as a screen coater, a Meyer bar coater, and a knife coater.

The drying conditions of the first pressure-sensitive adhesive composition are not particularly limited, but when the first pressure-sensitive adhesive composition contains a solvent described later, it is preferably heat-dried. In this case, for example, 70 to 130 ° C. It is preferable to dry under the condition of 10 seconds to 5 minutes.

When the first pressure-sensitive adhesive layer is energy ray-curable, the first pressure-sensitive adhesive composition containing the energy ray-curable pressure-sensitive adhesive, that is, the energy ray-curable first pressure-sensitive adhesive composition is, for example, non-energy. A first pressure-sensitive adhesive composition containing a linearly curable adhesive resin (I-1a) (hereinafter, may be abbreviated as "adhesive resin (I-1a)") and an energy ray-curable compound. (I-1); An 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-1a) (hereinafter, "adhesive"). The first pressure-sensitive adhesive composition (I-2) containing (sometimes abbreviated as "resin (I-2a)"); the pressure-sensitive adhesive resin (I-2a) and an energy ray-curable low-molecular-weight compound. Examples thereof include the first pressure-sensitive adhesive composition (I-3) contained therein.

<First Adhesive Composition (I-1)>
As described above, the first pressure-sensitive adhesive composition (I-1) contains a non-energy ray-curable pressure-sensitive adhesive resin (I-1a) and an energy ray-curable compound.

[Adhesive resin (I-1a)]
The adhesive resin (I-1a) is preferably an acrylic resin.
Examples of the acrylic resin include acrylic polymers having at least a structural unit derived from (meth) acrylic acid alkyl ester.
The structural unit of the acrylic resin may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

Examples of the (meth) acrylic acid alkyl ester include those in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is linear or branched. Is preferable.
More specifically, as the (meth) acrylic acid alkyl ester, methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-propyl (meth) acrylic acid, isopropyl (meth) acrylic acid, (meth) acrylic acid. n-butyl, 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, (meth) ) Undecyl acrylate, dodecyl (meth) acrylate (also called (meth) lauryl acrylate), tridecyl (meth) acrylate, tetradecyl (meth) acrylate (also called myristyl (meth) acrylate), (meth) acrylic Pentadecyl acrylate, hexadecyl (meth) acrylate (also called palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (also called stearyl (meth) acrylate), nonadecil (meth) acrylate , (Meta) icosyl acrylate and the like.

From the viewpoint of improving the adhesive strength of the first pressure-sensitive adhesive layer, the acrylic polymer preferably has a structural unit derived from a (meth) acrylic acid alkyl ester having 4 or more carbon atoms in the alkyl group. The alkyl group preferably has 4 to 12 carbon atoms, and more preferably 4 to 8 carbon atoms, from the viewpoint of further improving the adhesive strength of the first pressure-sensitive adhesive layer. Further, the (meth) acrylic acid alkyl ester having 4 or more carbon atoms in the alkyl group is preferably an acrylic acid alkyl ester.

The acrylic polymer preferably has a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the (meth) acrylic acid alkyl ester.
The functional group-containing monomer may be, for example, a starting point of cross-linking when the functional group reacts with a cross-linking agent described later, or when the functional group reacts with an unsaturated group in an unsaturated group-containing compound. Examples thereof include those capable of introducing an unsaturated group into the side chain of the acrylic polymer.

Examples of the functional group in the functional group-containing monomer include a hydroxyl group, a carboxy group, an amino group, an epoxy group and the like.
That is, examples of the functional group-containing monomer include a hydroxyl group-containing monomer, a carboxy group-containing monomer, an amino group-containing monomer, and an epoxy group-containing monomer.

Examples of the hydroxyl group-containing monomer include hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and (meth). (Meta) hydroxyalkyl acrylates such as 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate; non- (meth) acrylics such as vinyl alcohol and allyl alcohol. Saturated alcohol (unsaturated alcohol having no (meth) acrylic skeleton) and the like can be mentioned.

Examples of the carboxy group-containing monomer include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having ethylenically unsaturated bonds) such as (meth) acrylic acid and crotonic acid; fumaric acid, itaconic acid, maleic acid, and citracon. Ethylene unsaturated dicarboxylic acids such as acids (dicarboxylic acids having ethylenically unsaturated bonds); anhydrides of the ethylenically unsaturated dicarboxylic acids; (meth) acrylic acid carboxyalkyl esters such as 2-carboxyethyl methacrylate and the like. Be done.

As the functional group-containing monomer, a hydroxyl group-containing monomer and a carboxy group-containing monomer are preferable, and a hydroxyl group-containing monomer is more preferable.

The functional group-containing monomer constituting the acrylic polymer may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof 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, based on the total amount of the structural units. , 5 to 30% by mass is particularly preferable.

The acrylic polymer may further have a structural unit derived from another monomer in addition to the structural unit derived from the (meth) acrylic acid alkyl ester and the structural unit derived from the functional group-containing monomer.
The other monomer is not particularly limited as long as it can be copolymerized with a (meth) acrylic acid alkyl ester or the like.
Examples of the other monomer include styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide and the like.

The other monomer constituting the acrylic polymer may be only one kind, may be two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be arbitrarily selected.

The acrylic polymer can be used as the above-mentioned non-energy ray-curable adhesive resin (I-1a).
On the other hand, a product obtained by reacting a functional group in the acrylic polymer with an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group (energy ray-polymerizable group) has the above-mentioned energy ray-curable adhesiveness. It can be used as a resin (I-2a).
In the present invention, "energy ray-polymerizable" means the property of polymerizing by irradiating with energy rays.

The pressure-sensitive adhesive resin (I-1a) contained in the first pressure-sensitive adhesive composition (I-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof are It can be selected arbitrarily.

In the first pressure-sensitive adhesive composition (I-1), the content of the pressure-sensitive adhesive resin (I-1a) is 5 to 99% by mass with respect to the total mass of the first pressure-sensitive adhesive composition (I-1). It is preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass.

[Energy ray curable compound]
Examples of the energy ray-curable compound contained in the first pressure-sensitive adhesive composition (I-1) include monomers or oligomers having an energy ray-polymerizable unsaturated group and curable by irradiation with energy rays.
Among the energy ray-curable compounds, examples of the monomer include trimethylpropantri (meth) acrylate, pentaerythritol (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4. Polyvalent (meth) acrylates such as −butylene glycol di (meth) acrylate, 1,6-hexanediol (meth) acrylate; urethane (meth) acrylate; polyester (meth) acrylate; polyether (meth) acrylate; epoxy ( Meta) acrylate and the like can be mentioned.
Among the energy ray-curable compounds, examples of the oligomer include an oligomer obtained by polymerizing the monomers exemplified above.
Urethane (meth) acrylate and urethane (meth) acrylate oligomer are preferable as the energy ray-curable compound in that the molecular weight is relatively large and the storage elastic modulus of the first pressure-sensitive adhesive layer is unlikely to be lowered.

The energy ray-curable compound contained in the first pressure-sensitive adhesive composition (I-1) may be only one kind, two or more kinds, and when two or more kinds, the combination and ratio thereof are arbitrary. You can choose.

In the first pressure-sensitive adhesive composition (I-1), the content of the energy ray-curable compound is 1 to 95% by mass with respect to the total mass of the first pressure-sensitive adhesive composition (I-1). It is preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass.

[Crosslinking agent]
When the acrylic polymer having a structural unit derived from a functional group-containing monomer is used as the adhesive resin (I-1a) in addition to the structural unit derived from the (meth) acrylic acid alkyl ester, the first pressure-sensitive adhesive composition is used. The product (I-1) preferably further contains a cross-linking agent.

The cross-linking agent, for example, reacts with the functional group to cross-link the adhesive resins (I-1a) with each other.
Examples of the cross-linking agent include isocyanate-based cross-linking agents such as tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates (cross-linking agents having an isocyanate group); and epoxy-based cross-linking agents such as ethylene glycol glycidyl ether (cross-linking agents). Crosslinking agent having a glycidyl group); Isocyanate-based crosslinking agent such as hexa [1- (2-methyl) -aziridinyl] triphosphatriazine (crosslinking agent having an aziridinyl group); Metal chelate-based crosslinking agent such as aluminum chelate (metal) Cross-linking agent having a chelate structure); isocyanurate-based cross-linking agent (cross-linking agent having an isocyanurate skeleton) and the like.
The cross-linking agent is preferably an isocyanate-based cross-linking agent from the viewpoints of improving the cohesive force of the pressure-sensitive adhesive to improve the adhesive force of the first pressure-sensitive adhesive layer and being easily available.

The cross-linking agent contained in the first pressure-sensitive adhesive composition (I-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

In the first pressure-sensitive adhesive composition (I-1), the content of the cross-linking agent is 0.01 to 50 parts by mass with respect to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-1a). It is preferably 0.1 to 20 parts by mass, and particularly preferably 1 to 10 parts by mass.

[Photopolymerization initiator]
The first pressure-sensitive adhesive composition (I-1) may further contain a photopolymerization initiator. The first pressure-sensitive adhesive composition (I-1) containing a photopolymerization initiator sufficiently undergoes a curing reaction even when irradiated with relatively low-energy energy rays 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 benzoin benzoate, and benzoin dimethyl ketal; acetophenone, 2-hydroxy. Acetphenone compounds such as -2-methyl-1-phenyl-propane-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one; bis (2,4,6-trimethylbenzoyl) phenylphosphine Acylphosphine oxide compounds such as oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; sulfide compounds such as benzylphenyl sulfide and tetramethylthium monosulfide; α-ketol compounds such as 1-hydroxycyclohexylphenylketone; Azo compounds such as azobisisobutyronitrile; titanosen compounds such as titanosen; thioxanthone compounds such as thioxanthone; peroxide compounds; diketone compounds such as diacetyl; benzyl, dibenzyl, benzophenone, 2,4-diethylthioxanthone, 1,2- Examples thereof include diphenylmethane, 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone, 2-chloroanthraquinone and the like.
Further, as the photopolymerization initiator, for example, a quinone compound such as 1-chloroanthraquinone; a photosensitizer such as amine can be used.

The photopolymerization initiator contained in the first pressure-sensitive adhesive composition (I-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected. ..

In the first pressure-sensitive adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the content of the energy ray-curable compound. , 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass.

[Other additives]
The first pressure-sensitive adhesive composition (I-1) may contain other additives that do not fall under any of the above-mentioned components as long as the effects of the present invention are not impaired.
Examples of the other additives include antistatic agents, antioxidants, softeners (plasticizers), fillers (fillers), rust preventives, colorants (pigments, dyes), sensitizers, and tackifiers. , Known additives such as reaction retarders and cross-linking accelerators (catalysts).
The reaction delaying agent is used in the first pressure-sensitive adhesive composition (I-1) during storage due to the action of the catalyst mixed in the first pressure-sensitive adhesive composition (I-1). It suppresses the progress of the cross-linking reaction. Examples of the reaction retarder include those that form a chelate complex by chelating to a catalyst, and more specifically, those having two or more carbonyl groups (-C (= O)-) in one molecule. Can be mentioned.

The other additives contained in the first pressure-sensitive adhesive composition (I-1) may be only one kind, two or more kinds, and when there are two or more kinds, their combinations and ratios can be arbitrarily selected. ..

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

[solvent]
The first pressure-sensitive adhesive composition (I-1) may contain a solvent. Since the first pressure-sensitive adhesive composition (I-1) contains a solvent, the coating suitability on the surface to be coated is improved.

The solvent is preferably an organic solvent, and examples of the organic solvent include ketones such as methyl ethyl ketone and acetone; esters such as ethyl acetate (carboxylic acid esters); ethers such as tetrahydrofuran and dioxane; cyclohexane, n-hexane and the like. Hydrocarbons; 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) is used as it is in the first adhesive composition (I-1) without being removed from the adhesive resin (I-1a). Alternatively, the same or different type of solvent as that used in the production of the adhesive resin (I-1a) may be added separately during the production of the first pressure-sensitive adhesive composition (I-1).

The solvent contained in the first pressure-sensitive adhesive composition (I-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

In the first pressure-sensitive adhesive composition (I-1), the content of the solvent is not particularly limited and may be appropriately adjusted.

<First Adhesive Composition (I-2)>
As described above, the first pressure-sensitive adhesive composition (I-2) is an energy ray-curable pressure-sensitive adhesive in which an unsaturated group is introduced into the side chain of a non-energy ray-curable pressure-sensitive adhesive resin (I-1a). Contains a sex resin (I-2a).

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

In addition to the energy ray-polymerizable unsaturated group, the unsaturated group-containing compound can further bond with the adhesive resin (I-1a) by reacting with a functional group in the adhesive resin (I-1a). It is a compound having a group.
Examples of the energy ray-polymerizable unsaturated group include (meth) acryloyl group, vinyl group (ethenyl group), allyl group (2-propenyl group) and the like, and (meth) acryloyl group is preferable.
Examples of the group that can be bonded to the functional group in the adhesive resin (I-1a) include an isocyanate group and a glycidyl group that can be bonded to a hydroxyl group or an amino group, and a hydroxyl group and an amino group that can be bonded to a carboxy group or an epoxy group. And so on.

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

The pressure-sensitive adhesive resin (I-2a) contained in the first pressure-sensitive adhesive composition (I-2) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof are It can be selected arbitrarily.

In the first pressure-sensitive adhesive composition (I-2), the content of the pressure-sensitive adhesive resin (I-2a) is 5 to 99% by mass with respect to the total mass of the first pressure-sensitive adhesive composition (I-2). It is preferably 10 to 95% by mass, and particularly preferably 10 to 90% by mass.

[Crosslinking agent]
When the acrylic polymer having a structural unit derived from a functional group-containing monomer similar to that in the adhesive resin (I-1a) is used as the adhesive resin (I-2a), for example, the first pressure-sensitive adhesive composition. The product (I-2) may further contain a cross-linking agent.

Examples of the cross-linking agent in the first pressure-sensitive adhesive composition (I-2) include the same cross-linking agents as those in the first pressure-sensitive adhesive composition (I-1).
The cross-linking agent contained in the first pressure-sensitive adhesive composition (I-2) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

In the first pressure-sensitive adhesive composition (I-2), the content of the cross-linking agent is 0.01 to 50 parts by mass with respect to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a). It is preferably 0.1 to 20 parts by mass, and particularly preferably 1 to 10 parts by mass.

[Photopolymerization initiator]
The first pressure-sensitive adhesive composition (I-2) may further contain a photopolymerization initiator. The first pressure-sensitive adhesive composition (I-2) containing the photopolymerization initiator sufficiently promotes the curing reaction even when irradiated with relatively low-energy energy rays such as ultraviolet rays.

Examples of the photopolymerization initiator in the first pressure-sensitive adhesive composition (I-2) include the same photopolymerization initiators in the first pressure-sensitive adhesive composition (I-1).
The photopolymerization initiator contained in the first pressure-sensitive adhesive composition (I-2) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected. ..

In the first pressure-sensitive adhesive composition (I-2), the content of the photopolymerization initiator is 0.01 to 20 parts by mass with respect to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a). Is preferable, 0.03 to 10 parts by mass is more preferable, and 0.05 to 5 parts by mass is particularly preferable.

[Other additives]
The first pressure-sensitive adhesive composition (I-2) may contain other additives that do not fall under any of the above-mentioned components as long as the effects of the present invention are not impaired.
Examples of the other additive in the first pressure-sensitive adhesive composition (I-2) include the same as the other additives in the first pressure-sensitive adhesive composition (I-1).
The other additives contained in the first pressure-sensitive adhesive composition (I-2) may be only one kind, two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be arbitrarily selected. ..

The content of the other additives in the first pressure-sensitive adhesive composition (I-2) is not particularly limited, and may be appropriately selected depending on the type thereof.

[solvent]
The first pressure-sensitive adhesive composition (I-2) may contain a solvent for the same purpose as in the case of the first pressure-sensitive adhesive composition (I-1).
Examples of the solvent in the first pressure-sensitive adhesive composition (I-2) include the same solvents as those in the first pressure-sensitive adhesive composition (I-1).
The solvent contained in the first pressure-sensitive adhesive composition (I-2) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.
In the first pressure-sensitive adhesive composition (I-2), the content of the solvent is not particularly limited and may be appropriately adjusted.

<First Adhesive Composition (I-3)>
As described above, the first pressure-sensitive adhesive composition (I-3) contains the pressure-sensitive adhesive resin (I-2a) and an energy ray-curable low-molecular-weight compound.

In the first pressure-sensitive adhesive composition (I-3), the content of the pressure-sensitive adhesive resin (I-2a) is 5 to 99% by mass with respect to the total mass of the first pressure-sensitive adhesive composition (I-3). It is preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass.

[Energy ray-curable low molecular weight compound]
Examples of the energy ray-curable low molecular weight compound contained in the first pressure-sensitive adhesive composition (I-3) include monomers and oligomers having an energy ray-polymerizable unsaturated group and curable by irradiation with energy rays. , The same as the energy ray-curable compound contained in the first pressure-sensitive adhesive composition (I-1) can be mentioned.
The energy ray-curable low molecular weight compound contained in the first pressure-sensitive adhesive composition (I-3) may be only one kind, two or more kinds, and when there are two or more kinds, the combination and ratio thereof are It can be selected arbitrarily.

In the first pressure-sensitive adhesive composition (I-3), the content of the energy ray-curable low molecular weight compound is 0.01 to 300 with respect to 100 parts by mass of the content of the pressure-sensitive resin (I-2a). It is preferably parts by mass, more preferably 0.03 to 200 parts by mass, and particularly preferably 0.05 to 100 parts by mass.

[Photopolymerization initiator]
The first pressure-sensitive adhesive composition (I-3) may further contain a photopolymerization initiator. The first pressure-sensitive adhesive composition (I-3) containing the photopolymerization initiator sufficiently promotes the curing reaction even when irradiated with relatively low-energy energy rays such as ultraviolet rays.

Examples of the photopolymerization initiator in the first pressure-sensitive adhesive composition (I-3) include the same photopolymerization initiators in the first pressure-sensitive adhesive composition (I-1).
The photopolymerization initiator contained in the first pressure-sensitive adhesive composition (I-3) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected. ..

In the first pressure-sensitive adhesive composition (I-3), the content of the photopolymerization initiator is based on 100 parts by mass of the total content of the pressure-sensitive adhesive resin (I-2a) and the energy ray-curable low molecular weight compound. The amount 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.

[Other additives]
The first pressure-sensitive adhesive composition (I-3) may contain other additives that do not fall under any of the above-mentioned components as long as the effects of the present invention are not impaired.
Examples of the other additive include the same as the other additive in the first pressure-sensitive adhesive composition (I-1).
The other additives contained in the first pressure-sensitive adhesive composition (I-3) may be only one kind, two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be arbitrarily selected. ..

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

[solvent]
The first pressure-sensitive adhesive composition (I-3) may contain a solvent for the same purpose as in the case of the first pressure-sensitive adhesive composition (I-1).
Examples of the solvent in the first pressure-sensitive adhesive composition (I-3) include the same solvents as those in the first pressure-sensitive adhesive composition (I-1).
The solvent contained in the first pressure-sensitive adhesive composition (I-3) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.
In the first pressure-sensitive adhesive composition (I-3), the content of the solvent is not particularly limited and may be appropriately adjusted.

<First pressure-sensitive adhesive compositions other than the first pressure-sensitive adhesive compositions (I-1) to (I-3)>
Up to this point, the first pressure-sensitive adhesive composition (I-1), the first pressure-sensitive adhesive composition (I-2), and the first pressure-sensitive adhesive composition (I-3) have been mainly described, but the components contained therein. What has been described as is a general first pressure-sensitive adhesive composition other than these three types of first pressure-sensitive adhesive compositions (in the present specification, "first pressure-sensitive adhesive compositions (I-1) to (I-). It can also be used in the same manner with the first pressure-sensitive adhesive composition other than 3).

As the first pressure-sensitive adhesive composition other than the first pressure-sensitive adhesive compositions (I-1) to (I-3), in addition to the energy ray-curable pressure-sensitive adhesive composition, a non-energy ray-curable pressure-sensitive adhesive composition Can also be mentioned.
Examples of the non-energy ray-curable pressure-sensitive adhesive composition include acrylic resin (resin having a (meth) acryloyl group), urethane resin (resin having a urethane bond), and rubber resin (resin having a rubber structure). , Silicone resin (resin having siloxane bond), epoxy resin (resin having epoxy group), polyvinyl ether, or adhesive resin such as polycarbonate, and those containing acrylic resin are preferable. ..

The first pressure-sensitive adhesive compositions other than the first pressure-sensitive adhesive compositions (I-1) to (I-3) preferably contain one or more cross-linking agents, and the content thereof is the above-mentioned content. The same can be applied to the case of the first pressure-sensitive adhesive composition (I-1) and the like.

<< Manufacturing method of the first pressure-sensitive adhesive composition >>
The first pressure-sensitive adhesive composition such as the first pressure-sensitive adhesive compositions (I-1) to (I-3) is a first pressure-sensitive adhesive containing the pressure-sensitive adhesive and, if necessary, components other than the pressure-sensitive adhesive. It is obtained by blending each component for constituting the composition.
The order of addition of each component at the time of blending is not particularly limited, and two or more kinds of components may be added at the same time.
When a solvent is used, the solvent may be mixed with any compounding component other than the solvent and diluted in advance, or any compounding component other than the solvent may be diluted in advance. You may use it by mixing the solvent with these compounding components without leaving.
The method of mixing each component at the time of blending is not particularly limited, and from known methods such as a method of rotating a stirrer or a stirring blade to mix; a method of mixing using a mixer; a method of adding ultrasonic waves to mix. It may be selected as appropriate.
The temperature and time at the time of adding and mixing each component are not particularly limited as long as each compounding component does not deteriorate, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ° C.

○ First Intermediate Layer The first intermediate layer is in the form of a sheet or a film, and the constituent material thereof may be appropriately selected according to the purpose and is not particularly limited.
For example, when the purpose is to prevent the protective film from being deformed by reflecting the shape of the bumps existing on the semiconductor surface on the protective film covering the semiconductor surface, a preferable constituent material of the first intermediate layer is used. Examples thereof include urethane (meth) acrylate and the like from the viewpoint of further improving the adhesiveness of the first intermediate layer.

The first intermediate layer may be only one layer (single layer), may be a plurality of layers of two or more layers, and when there are a plurality of layers, the plurality of layers may be the same or different from each other, and a combination of the plurality of layers may be used. Is not particularly limited.

The thickness of the first intermediate layer can be appropriately adjusted according to the height of bumps on the surface of the semiconductor to be protected, but is 50 to 600 μm because the influence of bumps having a relatively high height can be easily absorbed. It is preferably 70 to 500 μm, more preferably 80 to 400 μm.
Here, the "thickness of the first intermediate layer" means the thickness of the entire first intermediate layer, and for example, the thickness of the first intermediate layer composed of a plurality of layers is all that constitute the first intermediate layer. Means the total thickness of the layers of.

<< Composition for forming the first intermediate layer >>
The first intermediate layer can be formed by using a composition for forming a first intermediate layer containing the constituent material.
For example, the composition for forming the first intermediate layer is applied to the surface to be formed of the first intermediate layer, dried as necessary, or cured by irradiation with energy rays, so that the target portion is first intermediate. Layers can be formed. A more specific method for forming the first intermediate layer will be described in detail later together with a method for forming the other layers. The ratio of the contents of the components that do not vaporize at room temperature in the composition for forming the first intermediate layer is usually the same as the ratio of the contents of the components in the first intermediate layer. Here, "normal temperature" is as described above.

The composition for forming the first intermediate layer may be applied by a known method, for example, an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, and a knife. Examples include a method using various coaters such as a coater, a screen coater, a Meyer bar coater, and a knife coater.

The drying conditions of the composition for forming the first intermediate layer are not particularly limited, but the composition for forming the first intermediate layer is preferably heat-dried when it contains a solvent described later, and in this case, for example, for example. It is preferable to dry at 70 to 130 ° C. for 10 seconds to 5 minutes.
When the composition for forming the first intermediate layer 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 first intermediate layer include the composition for forming the first intermediate layer (II-1) containing urethane (meth) acrylate.

<Composition for forming the first intermediate layer (II-1)>
The composition for forming the first intermediate layer (II-1) contains urethane (meth) acrylate as described above.

[Urethane (meth) acrylate]
Urethane (meth) acrylate is a compound having at least a (meth) acryloyl group and a urethane bond in one molecule, and has energy ray polymerization property.
Urethane (meth) acrylate may be monofunctional (having only one (meth) acryloyl group in one molecule) or bifunctional or more ((meth) acryloyl group in one molecule). (Those having two or more), that is, a polyfunctional one, but at least a monofunctional one is preferable.

The urethane (meth) acrylate contained in the product for forming the first intermediate layer includes, for example, a terminal isocyanate urethane prepolymer obtained by reacting a polyol compound with a polyvalent isocyanate compound, and further having a hydroxyl group and Examples thereof include those obtained by reacting a (meth) acrylic compound having a (meth) acryloyl group. Here, the "terminal isocyanate urethane prepolymer" means a prepolymer having a urethane bond and an isocyanate group at the terminal portion of the molecule.

The urethane (meth) acrylate contained in the composition for forming the first intermediate layer (II-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof are arbitrary. Can be selected.

(Polyol compound)
The polyol compound is not particularly limited as long as it is a compound having two or more hydroxyl groups in one molecule.
As the polyol compound, one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected.

Examples of the polyol compound include alkylene diols, polyether-type polyols, polyester-type polyols, and polycarbonate-type polyols.
The polyol compound may be any of a bifunctional diol, a trifunctional triol, a tetrafunctional or higher functional polyol, etc., but a diol is preferable in terms of easy availability, excellent versatility, reactivity and the like. ..

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

（式中、ｎは２以上の整数であり；Ｒは２価の炭化水素基であり、複数個のＲは互いに同一であっても異なっていてもよい。）

(In the formula, n is an integer of 2 or more; R is a divalent hydrocarbon group, and a plurality of Rs 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 "-RO-", and is not particularly limited as long as it is an integer of 2 or more. Among them, 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 divalent hydrocarbon group, but is preferably an alkylene group, more preferably an alkylene group having 1 to 6 carbon atoms, and an ethylene group, a propylene group or a tetra. It is more preferably a methylene group, and particularly preferably a propylene group or a tetramethylene group.

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

By reacting the polyether-type diol with the polyhydric isocyanate compound, a terminal isocyanate urethane prepolymer having an ether bond portion represented by the following general formula (1a) can be obtained. Then, by using such a terminal isocyanate urethane prepolymer, the urethane (meth) acrylate has the ether bond portion, that is, the constituent unit derived from the polyether type diol. ..

（式中、Ｒ及びｎは前記と同じである。）

(In the formula, R and n are the same as above.)

-Polyester-type polyol The polyester-type polyol is not particularly limited, and examples thereof include those obtained by carrying out an esterification reaction using a polybasic acid or a derivative thereof. In the present specification, the term "derivative" means a compound in which one or more groups of the original compound are substituted with other groups (substituents) unless otherwise specified. Here, the "group" includes not only an atomic group formed by bonding a plurality of atoms but also one atom.

Examples of the polybasic acid and its derivative include a polybasic acid and its derivative which are usually used as a raw material for producing polyester.
Examples of the polybasic acid include saturated aliphatic polybasic acid, unsaturated aliphatic polybasic acid, aromatic polybasic acid, and the like, and dimer acid corresponding to any of these may be used.

Examples of the saturated aliphatic dibasic acid include 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 dibasic 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; and pyromellitic acid. Aromatic tetrabasic acid and the like can be mentioned.

Examples of the derivative of the polybasic acid include the above-mentioned saturated aliphatic polybasic acid, unsaturated aliphatic polybasic acid and acid anhydride of aromatic polybasic acid, hydrogenated dimer acid and the like.

As for the polybasic acid or a derivative thereof, one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected. ..

The polybasic acid is preferably an aromatic polybasic acid in that it is suitable for forming a coating film having an appropriate hardness.

In the esterification reaction for obtaining a polyester-type polyol, a known catalyst may be used if necessary.
Examples of the catalyst include tin compounds such as dibutyltin oxide and stannous octylate; alkoxytitanium such as tetrabutyl titanate and tetrapropyl titanate.

-Polycarbonate-type polyol The polycarbonate-type polyol is not particularly limited, and examples thereof include those obtained by reacting a glycol similar to the compound represented by the above formula (1) with an alkylene carbonate.
Here, as the glycol and the alkylene carbonate, one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can 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 is suppressed, and it becomes easier to control the viscoelastic properties of the first intermediate layer. Further, when the number average molecular weight is 10,000 or less, excessive softening of the first intermediate layer is suppressed.
The 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] × 56.11 × 1000 / [Hydroxy group value of polyol compound (unit: mgKOH / g)]

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

(Multivalent isocyanate compound)
The multivalent isocyanate compound to be reacted with the polyol compound is not particularly limited as long as it has two or more isocyanate groups.
As the polyisocyanate compound, one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected.

Examples of the polyvalent isocyanate compound include chain aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate; isophorone diisocyanate, norbornan diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, and dicyclohexylmethane-2. , 4'-diisocyanate, ω, ω'-diisocyanate Diisocyanate Diisocyanate such as dimethylcyclohexane; 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, trizine diisocyanate, tetramethylene xylylene diisocyanate, naphthalene-1, Examples thereof include aromatic diisocyanates such as 5-diisocyanate.
Among these, the multivalent isocyanate compound is preferably isophorone diisocyanate, hexamethylene diisocyanate or xylylene diisocyanate from the viewpoint of handleability.

((Meta) acrylic compound)
The (meth) acrylic compound to be reacted with the terminal isocyanate urethane prepolymer is not particularly limited as long as it is a compound having at least a hydroxyl group and a (meth) acryloyl group in one molecule.
As the (meth) acrylic compound, one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected.

Examples of the (meth) acrylic compound include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 2-hydroxy (meth) acrylate. Butyl, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 5-hydroxycyclooctyl (meth) acrylate, 2-hydroxycyclooxy (meth) acrylate Hydroxyl-containing (meth) acrylic acid esters such as hydroxy-3-phenyloxypropyl, pentaerythritol tri (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate; N-methylol (meth) acrylamide, etc. The hydroxyl group-containing (meth) acrylamide; a reaction product obtained by reacting vinyl alcohol, vinylphenol, or bisphenol A diglycidyl ether with (meth) acrylic acid can be mentioned.
Among these, the (meth) acrylic compound is preferably a hydroxyl group-containing (meth) acrylic acid ester, more preferably a hydroxyl group-containing (meth) acrylic acid alkyl ester, and (meth) acrylic acid 2-. Hydroxyethyl is particularly preferred.

The reaction between the terminal isocyanate urethane prepolymer and the (meth) acrylic compound may be carried out using a solvent, a catalyst or the like, if necessary.

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

The urethane (meth) acrylate may be any of an oligomer, a polymer, and a mixture of the oligomer and the polymer, but is preferably an oligomer.
For example, the weight average molecular weight of the urethane (meth) acrylate is preferably 1000 to 100,000, more preferably 3000 to 80000, and particularly preferably 5000 to 65000. When the weight average molecular weight is 1000 or more, in the polymer of urethane (meth) acrylate and the polymerizable monomer described later, the first intermediate is caused by the intermolecular force between the structures derived from urethane (meth) acrylate. It is easy to optimize the hardness of the layer.
In the present specification, the weight average molecular weight is a polystyrene-equivalent value measured by a gel permeation chromatography (GPC) method unless otherwise specified.

[Polymerizable monomer]
The composition for forming the first intermediate layer (II-1) may contain a polymerizable monomer in addition to the urethane (meth) acrylate from the viewpoint of further improving the film-forming property.
The polymerizable monomer is a compound having energy ray polymerizable properties, excluding oligomers and polymers having a weight average molecular weight of 1000 or more, and having at least one (meth) acryloyl group in one molecule. Is preferable.

Examples of the polymerizable monomer include a (meth) acrylic acid alkyl ester in which the alkyl group constituting the alkyl ester has 1 to 30 carbon atoms and is chain-like; a hydroxyl group, an amide group, an amino group, an epoxy group, or the like. Functional group-containing (meth) acrylic compound having a functional group of; (meth) acrylic acid ester having an aliphatic cyclic group; (meth) acrylic acid ester having an aromatic hydrocarbon group; having a heterocyclic group ( Meta) Acrylic acid ester; a compound having a vinyl group; a compound having an allyl group and the like can be mentioned.

Examples of the (meth) acrylic acid alkyl ester having a chain alkyl group having 1 to 30 carbon atoms include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, and n-propyl (meth) acrylic acid. Isopropyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, (meth) Hexyl acrylate, heptyl (meth) acrylate, n-octyl acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate, (meth) acrylate Isononyl, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate (lauryl (meth) acrylate), tridecyl (meth) acrylate, tetradecyl (meth) acrylate ((meth) acrylate) Myristyl), pentadecyl (meth) acrylate, hexadecyl (meth) acrylate (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), (meth) ) Isooctadecyl acrylate (isostearyl (meth) acrylate), nonadecil (meth) acrylate, icosyl (meth) acrylate and the like can be mentioned.

Examples of the functional group-containing (meth) acrylic acid derivative include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and (meth) acrylate. Group-containing (meth) acrylic acid esters such as 2-hydroxybutyl, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate; (meth) acrylamide, N, N-dimethyl (meth) acrylamide, (Meta) acrylamides such as N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide and the like. Derivatives: (meth) acrylic acid ester having an amino group (hereinafter, may be referred to as "amino group-containing (meth) acrylic acid ester"); one hydrogen atom of the amino group is replaced with a group other than the hydrogen atom. (Meta) acrylic acid ester having a mono-substituted amino group (hereinafter, may be referred to as "mono-substituted amino group-containing (meth) acrylic acid ester"); the two hydrogen atoms of the amino group are other than hydrogen atoms. A (meth) acrylic acid ester having a disubstituted amino group substituted with a group (hereinafter, may be referred to as "disubstituted amino group-containing (meth) acrylic acid ester"); glycidyl (meth) acrylate, (meth). ) (Meta) acrylic acid ester having an epoxy group such as methylglycidyl acrylate (hereinafter, may be referred to as "epoxy group-containing (meth) acrylic acid ester") and the like.

Here, the "amino group-containing (meth) acrylic acid ester" means a compound in which one or more hydrogen atoms of the (meth) acrylic acid ester are substituted with an amino group (-NH ₂ ). .. Similarly, the "mono-substituted amino group-containing (meth) acrylic acid ester" means a compound in which one or more hydrogen atoms of the (meth) acrylic acid ester are substituted with a mono-substituted amino group. The "disubstituted amino group-containing (meth) acrylic acid ester" means a compound in which one or more hydrogen atoms of the (meth) acrylic acid ester are substituted with a disubstituted amino group.
Examples of the group other than the hydrogen atom (that is, the substituent) in which the hydrogen atom is substituted in the "mono-substituted amino group" and the "di-substituted amino group" include an alkyl group and the like.

Examples of the (meth) acrylic acid ester having an aliphatic cyclic group include isobornyl (meth) acrylic acid, dicyclopentenyl (meth) acrylic acid, dicyclopentanyl (meth) acrylic acid, and (meth) acrylic acid. Examples thereof include dicyclopentenyloxyethyl, cyclohexyl (meth) acrylate, and adamantyl (meth) acrylate.

Examples of the (meth) acrylic acid ester having an aromatic hydrocarbon group include phenylhydroxypropyl (meth) acrylate, benzyl (meth) acrylate, and 2-hydroxy-3-phenoxypropyl (meth) acrylate. Can be mentioned.

The heterocyclic group in the (meth) acrylic acid ester having a heterocyclic group may be either an aromatic heterocyclic group or an aliphatic heterocyclic group.
Examples of the (meth) acrylic acid ester having a heterocyclic group include tetrahydrofurfuryl (meth) acrylic acid and (meth) acryloyl morpholine.

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 relatively bulky group from the viewpoint of having good compatibility with the urethane (meth) acrylate, and such a monomer has an aliphatic cyclic group (meth). ) Acrylate ester, (meth) acrylic acid ester having an aromatic hydrocarbon group, (meth) acrylic acid ester having a heterocyclic group, and (meth) acrylic acid ester having an aliphatic cyclic group are more suitable. preferable.

The polymerizable monomer contained in the first intermediate layer forming composition (II-1) may be only one type, two or more types, and when two or more types, the combination and ratio thereof can be arbitrarily selected. it can.

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

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

Examples of the photopolymerization initiator in the composition for forming the first intermediate layer (II-1) include the same photopolymerization initiator in the first pressure-sensitive adhesive composition (I-1).

The photopolymerization initiator contained in the first intermediate layer forming composition (II-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof may be arbitrary. You can choose.

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

[Resin components other than urethane (meth) acrylate]
The composition for forming the first intermediate layer (II-1) may contain a resin component other than the urethane (meth) acrylate as long as the effects of the present invention are not impaired.
The type of the resin component and the content thereof in the composition for forming the first intermediate layer (II-1) may be appropriately selected depending on the intended purpose, and are not particularly limited.

[Other additives]
The composition for forming the first intermediate layer (II-1) may contain other additives that do not correspond to any of the above-mentioned components as long as the effects of the present invention are not impaired.
Known examples of the other additives include cross-linking agents, antistatic agents, antioxidants, chain transfer agents, softeners (plasticizers), fillers, rust inhibitors, colorants (pigments, dyes) and the like. Additives can be mentioned.
For example, examples of the chain transfer agent include thiol compounds having at least one thiol group (mercapto group) in one molecule.

Examples of the thiol compound include nonyl mercaptan, 1-dodecanethiol, 1,2-ethanedithiol, 1,3-propanedithiol, triazinethiol, triazinedithiol, triazinetrithiol, 1,2,3-propanetrithiol, and the like. Tetraethylene glycol-bis (3-mercaptopropionate), trimetylolpropanthris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetraxthioglucolate, dipentaerythritol hexa Kiss (3-mercaptopropionate), Tris [(3-mercaptopropioniroxy) -ethyl] -isocyanurate, 1,4-bis (3-mercaptobutyryloxy) butane, pentaerythritol tetrakis (3-mercaptobuty) Rate), 1,3,5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione and the like.

The other additives contained in the first intermediate layer forming composition (II-1) may be only one kind, two or more kinds, and when there are two or more kinds, the combination and ratio thereof are arbitrary. You can choose.

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

[solvent]
The composition for forming the first intermediate layer (II-1) may contain a solvent. Since the composition for forming the first intermediate layer (II-1) contains a solvent, the suitability for coating on the surface to be coated is improved.

<< Method for Producing Composition for Forming First Intermediate Layer >>
The first intermediate layer forming composition such as the first intermediate layer forming composition (II-1) can be obtained by blending each component for forming the first intermediate layer forming composition.
The order of addition of each component at the time of blending is not particularly limited, and two or more kinds of components may be added at the same time.
When a solvent is used, the solvent may be mixed with any compounding component other than the solvent and diluted in advance, or any compounding component other than the solvent may be diluted in advance. You may use it by mixing the solvent with these compounding components without leaving.
The method of mixing each component at the time of blending is not particularly limited, and from known methods such as a method of rotating a stirrer or a stirring blade to mix; a method of mixing using a mixer; a method of adding ultrasonic waves to mix. It may be selected as appropriate.
The temperature and time at the time of adding and mixing each component are not particularly limited as long as each compounding component does not deteriorate, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ° C.

(◎ Thermosetting resin layer) The thermosetting resin layer is a layer for protecting a circuit surface of a semiconductor wafer and bumps provided on the circuit surface, and forms a first protective film by curing.

Preferred thermosetting resin layers include, for example, those containing a polymer component (A) and a thermosetting component (B). The polymer component (A) is a component that can be regarded as being formed by a polymerization reaction of a polymerizable compound. Further, the thermosetting component (B) is a component capable of undergoing a curing (polymerization) reaction by using heat as a trigger for the reaction. In the present invention, the polymerization reaction also includes a polycondensation reaction.

The thermosetting resin layer may be only one layer (single layer), may be two or more layers, or may be a plurality of layers. In the case of a plurality of layers, the plurality of layers may be the same or different from each other, and these plurality of layers may be used. The combination of 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. When the thickness of the thermosetting resin layer is at least the above lower limit value, a first protective film having a higher protective ability can be formed. Further, when the thickness of the thermosetting resin layer is not more than the upper limit value, the effect of suppressing the inclusion of air bubbles in the first protective film becomes higher.
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 is the thermosetting resin layer. It means the total thickness of all the layers that make up.

<< Composition for forming a thermosetting resin layer >>
The thermosetting resin layer can be formed by using a composition for forming a thermosetting resin layer containing the constituent material. For example, a thermosetting resin layer can be formed at a target portion by applying a composition for forming a thermosetting resin layer to a surface to be formed of the thermosetting resin layer and drying it if necessary. The ratio of the contents of the components that do not vaporize at room temperature in the composition for forming the thermosetting resin layer is usually the same as the ratio of the contents of the components of the thermosetting resin layer. Here, "normal temperature" is as described above.

The composition for forming a thermosetting resin layer may be applied by a known method, for example, an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, and the like. Examples thereof include a method using various coaters such as a knife coater, a screen coater, a Meyer bar coater, and a kiss coater.

The drying conditions of the thermosetting resin layer forming composition are not particularly limited, but the thermosetting resin layer forming composition is preferably heat-dried when it contains a solvent described later. In this case, For example, it is preferable to dry at 70 to 130 ° C. for 10 seconds to 5 minutes.

<Composition for forming a resin layer (III-1)>
As the thermosetting resin layer forming composition, for example, the thermosetting resin layer forming composition (III-1) containing the polymer component (A) and the thermosetting component (B) (in the present specification). May be simply abbreviated as "resin layer forming composition (III-1)") and the like.

[Polymer component (A)]
The polymer component (A) is a polymer compound for imparting film-forming property, flexibility, etc. 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 only one kind, two or more kinds, and when two or more kinds, those The combination and ratio can be selected arbitrarily.

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

Examples of the acrylic resin in the polymer component (A) include known acrylic polymers.
The weight average molecular weight (Mw) of the acrylic resin is preferably 1000 to 2000000, and more preferably 100,000 to 1500,000. When the weight average molecular weight of the acrylic resin is at least the above lower limit value, 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 upper limit value, 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 ° C, more preferably -30 to 50 ° C. When the Tg of the acrylic resin is at least the above lower limit value, the adhesive force between the first protective film and the first support sheet is suppressed, and the peelability of the first support sheet is improved. Further, when the Tg of the acrylic resin is not more than the above upper limit value, the adhesive force between the thermosetting resin layer and the first protective film with the adherend is improved.

The acrylic resin is selected from, for example, a polymer of one or more (meth) acrylic acid esters; (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylol acrylamide, and the like. Examples thereof include copolymers of two or more types of monomers.

Examples of the (meth) acrylic acid ester constituting the acrylic resin include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-propyl (meth) acrylic acid, isopropyl (meth) acrylic acid, and (meth). ) N-butyl acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylic Heptyl acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate , (Meta) undecyl acrylate, (meth) dodecyl acrylate ((meth) lauryl acrylate), (meth) tridecyl acrylate, tetradecyl (meth) acrylate (myristyl (meth) acrylate), (meth) acrylate The alkyl groups constituting the alkyl ester, such as pentadecyl, hexadecyl (meth) acrylate (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), (Meta) acrylic acid alkyl ester having a chain structure with 1 to 18 carbon atoms;
(Meta) Acrylic acid cycloalkyl esters such as (meth) acrylate isobornyl, (meth) acrylate dicyclopentanyl;
(Meta) Acrylic acid aralkyl esters such as benzyl (meth) acrylic acid;
(Meta) Acrylic acid cycloalkenyl ester such as (meth) acrylic acid dicyclopentenyl ester;
(Meta) Acrylic acid cycloalkenyloxyalkyl ester such as (meth) acrylic acid dicyclopentenyloxyethyl ester;
(Meta) acrylate imide;
A glycidyl group-containing (meth) acrylic acid ester such as glycidyl (meth) acrylate;
Hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, (meth) ) Hydroxyl-containing (meth) acrylic acid esters such as 3-hydroxybutyl acrylate and 4-hydroxybutyl (meth) acrylate;
Examples thereof include substituted amino group-containing (meth) acrylic acid esters such as N-methylaminoethyl (meth) acrylic acid. Here, the "substituted amino group" means a group in which one or two hydrogen atoms of the amino group are substituted with a group other than the hydrogen atom.

The acrylic resin is, for example, one or more monomers selected from (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide and the like, in addition to the (meth) acrylic acid ester. May be copolymerized with each other.

The monomer constituting the acrylic resin may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

The acrylic resin may have a functional group capable of binding to other compounds such as a vinyl group, a (meth) acryloyl group, an amino group, a hydroxyl group, a carboxy group and an isocyanate group. The functional group of the acrylic resin may be bonded to another compound via a cross-linking agent (F) described later, or may be directly bonded to another compound without a cross-linking agent (F). .. When the acrylic resin is bonded to another compound by the functional group, the reliability of the package obtained by using the protective film forming sheet tends to be improved.

In the present invention, as the polymer component (A), a thermoplastic resin other than the acrylic resin (hereinafter, may be simply abbreviated as “thermoplastic resin”) is used alone without using the acrylic resin. It may be used in combination with an acrylic resin. By using the thermoplastic resin, the peelability of the first protective film from the first support sheet is improved, and the thermosetting resin layer easily follows the uneven surface of the adherend.

The weight average molecular weight of the thermoplastic resin is preferably 1000 to 100,000, more preferably 3000 to 80,000.

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

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

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

In the resin layer forming composition (III-1), the ratio of the content of the polymer component (A) to the total content of all the components other than the solvent (that is, the polymer component (A) of the thermosetting resin layer). Content) is preferably 5 to 85% by mass, more preferably 5 to 80% by mass, regardless of the type of the polymer component (A).

The polymer component (A) may also correspond to the thermosetting component (B). In the present invention, when the composition for forming a resin layer (III-1) contains a component corresponding to both the polymer component (A) and the thermosetting component (B), it is used for forming a resin layer. The composition (III-1) is considered to contain 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 first protective film.
The composition for forming a resin layer (III-1) and the thermosetting component (B) contained in the thermosetting resin layer may be only one kind, may be two or more kinds, and when two or more kinds, they may be used. The combination and ratio of are arbitrarily selectable.

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

(Epoxy thermosetting resin)
The epoxy-based thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2).
The epoxy-based thermosetting resin contained in the resin layer forming composition (III-1) and the thermosetting resin layer may be only one kind, two or more kinds, and when two or more kinds, those The combination and ratio can be selected arbitrarily.

・ Epoxy resin (B1)
Examples of the epoxy resin (B1) include known ones, such as polyfunctional epoxy resin, biphenyl compound, bisphenol A diglycidyl ether and its hydrogenated product, orthocresol novolac epoxy resin, dicyclopentadiene type epoxy resin, and the like. Biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin, and other bifunctional or higher functional epoxy compounds can be mentioned.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group may be used. An epoxy resin having an unsaturated hydrocarbon group has higher compatibility with an acrylic resin than an epoxy resin having no unsaturated hydrocarbon group. Therefore, by using an epoxy resin having an unsaturated hydrocarbon group, the reliability of the package obtained by using the protective film forming sheet is improved.

Examples of the epoxy resin having an unsaturated hydrocarbon group include a compound obtained by converting a part of the epoxy group of the polyfunctional epoxy resin into a group having an unsaturated hydrocarbon group. Such a compound can be obtained, for example, by subjecting an epoxy group to an addition reaction of (meth) acrylic acid or a derivative thereof.
Examples of the epoxy resin having an unsaturated hydrocarbon group include a compound in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting the epoxy resin.
The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethenyl group (vinyl group), a 2-propenyl group (allyl group), a (meth) acryloyl group, and a (meth) group. Examples thereof include an acrylamide group, and an acryloyl group is preferable.

The number average molecular weight of the epoxy resin (B1) is not particularly limited, but is preferably 300 to 30,000 from the viewpoint of the curability of the thermosetting resin layer and the strength and heat resistance of the first protective film after curing. , 400 to 10000, and particularly preferably 500 to 3000.
As used herein, "number average molecular weight" means a number average molecular weight represented by a standard 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 1000 g / eq, more preferably 300 to 800 g / eq.
As used herein, the term "epoxy equivalent" means the number of grams (g / eq) of an epoxy compound containing 1 gram equivalent of an epoxy group, and can be measured according to the method of JIS K 7236: 2001.

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

・ Thermosetting agent (B2)
The thermosetting agent (B2) functions as a curing agent for the epoxy resin (B1).
Examples of the thermosetting agent (B2) include compounds having two or more functional groups capable of reacting with epoxy groups in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxy group, a group in which an acid group is anhydrous, and the phenolic hydroxyl group, an amino group, or an acid group is anhydrous. It is preferably a group, more preferably a phenolic hydroxyl group or an amino group.

Among the thermosetting agents (B2), examples of the phenolic curing agent having a phenolic hydroxyl group include polyfunctional phenolic resin, biphenol, novolak type phenolic resin, dicyclopentadien phenolic resin, and aralkylphenolic resin.
Among the thermosetting agents (B2), examples of the amine-based curing agent having an amino group include dicyandiamide (hereinafter, may be abbreviated as "DICY") and the like.

The thermosetting agent (B2) may have an unsaturated hydrocarbon group.
The thermosetting agent (B2) having an unsaturated hydrocarbon group is, for example, a compound in which a part of the hydroxyl group of the phenol resin is replaced with a group having an unsaturated hydrocarbon group, which is not suitable for the aromatic ring of the phenol resin. Examples thereof include compounds in which a group having a saturated hydrocarbon group is directly bonded.
The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the epoxy resin having the unsaturated hydrocarbon group described above.

When a phenolic curing agent is used as the thermosetting agent (B2), the thermosetting agent (B2) has a softening point or a glass transition temperature because the peelability of the first protective film from the first support sheet is improved. Higher ones are preferable.

Among the thermosetting agents (B2), the number average molecular weight of resin components such as polyfunctional phenol resin, novolak type phenol resin, dicyclopentadiene phenol resin, and aralkyl phenol resin is preferably 300 to 30,000. It is 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.

As the thermosetting agent (B2), one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected.

In the resin layer forming composition (III-1) and the thermosetting resin layer, the content of the thermosetting agent (B2) is 0.1 to 500 with respect to 100 parts by mass of the content of the epoxy resin (B1). It is preferably parts by mass, more preferably 1 to 200 parts by mass. When the content of the thermosetting agent (B2) is at least the lower limit value, the curing of the thermosetting resin layer becomes easier to proceed. Further, when the content of the thermosetting agent (B2) is not more than the upper limit value, the hygroscopicity of the thermosetting resin layer is reduced, and the reliability of the package obtained by using the protective film forming sheet is obtained. Is 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 The content of the polymer component (A) 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 with respect to 100 parts by mass. preferable. When the content of the thermosetting component (B) is in such a range, the adhesive force between the first protective film and the first support sheet is suppressed, and the peelability of the first support sheet is improved.

[Curing accelerator (C)]
The resin layer forming composition (III-1) and the thermosetting resin layer 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 curing accelerators (C) include, for example, tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol and tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole. , 2-Phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole and other imidazoles (one or more hydrogen atoms other than hydrogen atoms) (Imidazole substituted with an organic group); organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine (phosphine in which one or more hydrogen atoms are substituted with an organic group); tetraphenylphosphonium tetraphenylborate, triphenylphosphine Examples thereof include tetraphenylborone salts such as tetraphenylborate.

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

When the curing accelerator (C) is used, the content of the curing accelerator (C) in the resin layer forming composition (III-1) and the thermosetting resin layer is the content of the thermosetting component (B). It is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass. When the content of the curing accelerator (C) is at least the lower limit value, the effect of using the curing accelerator (C) is more remarkable. Further, when the content of the curing accelerator (C) is not more than the above upper limit value, for example, the highly polar curing accelerator (C) is adhered in the thermosetting resin layer under high temperature and high humidity conditions. The effect of suppressing segregation by moving to the adhesion interface side with the body is enhanced, and the reliability of the package obtained by 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). Since the thermosetting resin layer contains the filler (D), the first protective film obtained by curing the thermosetting resin layer has an easy adjustment of the coefficient of thermal expansion, and the coefficient of thermal expansion is set to the second. (1) By optimizing for the object to be formed of the protective film, the reliability of the package obtained by using the protective film forming sheet is further improved. Further, when the thermosetting resin layer contains the filler (D), the hygroscopicity of the first protective film can be reduced and the heat dissipation can be improved.

The filler (D) may be either an organic filler or an inorganic filler, but is preferably an inorganic filler.
Preferred inorganic fillers include, for example, powders of silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, boron nitride and the like; spherical beads of these inorganic fillers; surface modification of these inorganic fillers. Goods; Single crystal fibers of these inorganic fillers; Glass fibers and the like.
Among these, the inorganic filler is preferably silica or alumina.

The resin layer forming composition (III-1) and the filler (D) contained in the thermosetting resin layer may be only one type, two or more types, or a combination thereof when two or more types are used. And the ratio can be selected arbitrarily.

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

[Coupling agent (E)]
The resin layer forming composition (III-1) and the thermosetting resin layer may contain a coupling agent (E). By using a coupling agent (E) having a functional group capable of reacting with an inorganic compound or an organic compound, the adhesiveness and adhesion of the thermosetting resin layer to the adherend can be improved. Further, by using the coupling agent (E), the first protective film obtained by curing the thermosetting resin layer has improved water resistance without impairing heat resistance.

The coupling agent (E) is preferably a compound having a functional group capable of reacting with the functional groups of the polymer component (A), the thermosetting component (B) and the like, and is preferably a silane coupling agent. More preferred.
Preferred silane coupling agents include, for example, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2-. (3,4-Epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxysilane, 3- (2-amino) Ethylamino) propylmethyldiethoxysilane, 3- (phenylamino) propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyl Examples thereof include dimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazolesilane.

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

When the coupling agent (E) is used, the content of the coupling agent (E) in the resin layer forming composition (III-1) and the thermosetting resin layer is the polymer component (A) and the thermosetting resin layer. The total content of the component (B) is preferably 0.03 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, and 0.1 to 5 parts by mass with respect to 100 parts by mass. It is particularly preferable to have. When the content of the coupling agent (E) is equal to or higher than the lower limit, the dispersibility of the filler (D) in the resin is improved and the adhesiveness of the thermosetting resin layer to the adherend is improved. The effect of using the coupling agent (E) is more remarkable. Further, when the content of the coupling agent (E) is not more than the upper limit value, the generation of outgas is further suppressed.

[Crosslinking agent (F)]
As the polymer component (A), one having a functional group such as a vinyl group capable of binding to another compound such as the above-mentioned acrylic resin, a (meth) acryloyl group, an amino group, a hydroxyl group, a carboxy group and an isocyanate group. When used, the resin layer forming composition (III-1) and the thermosetting resin layer may contain a cross-linking agent (F) for bonding the functional group with another compound to cross-link. By cross-linking with the cross-linking agent (F), the initial adhesive force and cohesive force of the thermosetting resin layer can be adjusted.

Examples of the cross-linking agent (F) include an organic polyvalent isocyanate compound, an organic polyvalent imine compound, a metal chelate-based cross-linking agent (cross-linking agent having a metal chelate structure), an aziridine-based cross-linking agent (cross-linking agent having an aziridinyl group) and the like. Can be mentioned.

Examples of the organic polyvalent isocyanate compound include an aromatic polyvalent isocyanate compound, an aliphatic polyvalent isocyanate compound, and an alicyclic polyvalent isocyanate compound (hereinafter, these compounds are collectively referred to as “aromatic polyvalent isocyanate compound and the like”. (May be abbreviated); trimerics such as the aromatic polyvalent isocyanate compound, isocyanurates and adducts; terminal isocyanate urethane prepolymer obtained by reacting the aromatic polyvalent isocyanate compound and the like with a polyol compound. And so on. The "adduct" is a low content of the aromatic polyhydric isocyanate compound, the aliphatic polyvalent isocyanate compound or the alicyclic polyvalent isocyanate compound, and ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil and the like. It means a reaction product with a molecularly active hydrogen-containing compound, and examples thereof include a xylylene diisocyanate adduct of trimethylol propane as described later. Further, the "terminal isocyanate urethane prepolymer" is as described above.

More specifically, as the organic polyvalent isocyanate compound, for example, 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; 1,3-xylylene diisocyanate; 1,4-xylene diisocyanate; diphenylmethane-4. , 4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; trimethylol Compounds in which one or more of tolylene diisocyanate, hexamethylene diisocyanate and xylylene diisocyanate are added to all or some hydroxyl groups of a polyol such as propane; lysine diisocyanate and the like can be mentioned.

Examples of the organic polyvalent imine compound include N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxyamide), trimethylpropan-tri-β-aziridinyl propionate, and tetramethylolmethane. Examples thereof include -tri-β-aziridinyl propionate, N, N'-toluene-2,4-bis (1-aziridinecarboxyamide) triethylene melamine and the like.

When an organic multivalent isocyanate compound is used as the cross-linking agent (F), it is preferable to use a hydroxyl group-containing polymer as the polymer component (A). When the cross-linking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, the reaction between the cross-linking agent (F) and the polymer component (A) causes the thermosetting resin layer to have a cross-linked structure. Can be easily introduced.

The cross-linking agent (F) contained in the resin layer forming composition (III-1) and the thermosetting resin layer may be only one kind, two or more kinds, and when two or more kinds, a combination thereof. And the ratio can be selected arbitrarily.

When the cross-linking agent (F) is used, the content of the cross-linking agent (F) in the resin layer forming composition (III-1) is 0, based on 100 parts by mass of the content of the polymer component (A). It is preferably 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. When the content of the cross-linking agent (F) is at least the lower limit value, the effect of using the cross-linking agent (F) is more remarkable. Further, when the content of the cross-linking agent (F) is not more than the upper limit value, the excessive use of the cross-linking agent (F) is suppressed.

[Energy ray curable resin (G)]
The resin layer forming composition (III-1) may contain an energy ray-curable resin (G). Since the thermosetting resin layer contains the energy ray-curable resin (G), its characteristics can be changed by irradiation with energy rays.

The energy ray-curable resin (G) is obtained by polymerizing (curing) an energy ray-curable compound.
Examples of the energy ray-curable compound include compounds having at least one polymerizable double bond in the molecule, and acrylate-based compounds having a (meth) acryloyl group are preferable.

Examples of the acrylate-based compound include trimethyl propantri (meth) acrylate, tetramethylol methanetetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and dipentaerythritol monohydroxypenta ( Chain aliphatic skeleton-containing (meth) acrylates such as meta) acrylates, dipentaerythritol hexa (meth) acrylates, 1,4-butylene glycol di (meth) acrylates, and 1,6-hexanediol di (meth) acrylates; Cyclic aliphatic skeleton-containing (meth) acrylate such as cyclopentanyldi (meth) acrylate; Polyalkylene glycol (meth) acrylate such as polyethylene glycol di (meth) acrylate; Oligoester (meth) acrylate; Urethane (meth) acrylate oligomer ; Epoxy-modified (meth) acrylate; polyether (meth) acrylate other than the polyalkylene glycol (meth) acrylate; itaconic acid oligomer and the like.

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

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

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

[Photopolymerization Initiator (H)]
When the resin layer forming composition (III-1) contains the energy ray-curable resin (G), the photopolymerization initiator (H) is used to efficiently proceed with the polymerization reaction of the energy ray-curable resin (G). ) May be contained.

Examples of the photopolymerization initiator (H) in the resin layer forming composition (III-1) include the same photopolymerization initiator (I-1) as in the first pressure-sensitive adhesive composition (I-1).

The photopolymerization initiator (H) contained in the resin layer forming composition (III-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof are arbitrary. Can be selected.

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

[General-purpose additive (I)]
The resin layer forming composition (III-1) and the thermosetting resin layer may contain the general-purpose additive (I) as long as the effects of the present invention are not impaired.
The general-purpose additive (I) may be a known one, and may be arbitrarily selected depending on the intended purpose, and is not particularly limited, but preferred ones are, for example, plasticizers, antistatic agents, antioxidants, and colorants (dye). , Pigments), gettering agents and the like.

The general-purpose additive (I) contained in the resin layer forming composition (III-1) and the thermosetting resin layer may be only one kind, two or more kinds, and when two or more kinds, those The combination and ratio can be selected arbitrarily.
The contents of the resin layer forming composition (III-1) and the general-purpose additive (I) of the thermosetting resin layer are not particularly limited and may be appropriately selected depending on the intended purpose.

[solvent]
The resin layer forming composition (III-1) preferably further contains a solvent. The resin layer forming composition (III-1) containing a solvent has good handleability.
The solvent is not particularly limited, but preferred ones are, for example, hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutyl alcohol (2-methylpropan-1-ol) and 1-butanol. Examples thereof include esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides such as dimethylformamide and N-methylpyrrolidone (compounds having an amide bond).
The solvent contained in the resin layer forming composition (III-1) may be only one type, may be two or more types, and when there are two or more types, 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 that the components contained in the resin layer forming composition (III-1) can be mixed more uniformly.

<< Manufacturing method of composition for forming thermosetting resin layer >>
A thermosetting resin layer forming composition such as the resin layer forming composition (III-1) can be obtained by blending each component for forming the same.
The order of addition of each component at the time of blending is not particularly limited, and two or more kinds of components may be added at the same time.
When a solvent is used, the solvent may be mixed with any compounding component other than the solvent and diluted in advance, or any compounding component other than the solvent may be diluted in advance. You may use it by mixing the solvent with these compounding components without leaving.
The method of mixing each component at the time of blending is not particularly limited, and from known methods such as a method of rotating a stirrer or a stirring blade to mix; a method of mixing using a mixer; a method of adding ultrasonic waves to mix. It may be selected as appropriate.
The temperature and time at the time of adding and mixing each component are not particularly limited as long as each compounding component does not deteriorate, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ° C.

-Method of manufacturing a protective film forming sheet The protective film forming sheet can be manufactured by sequentially laminating the above-mentioned layers so as to have a corresponding positional relationship. The method of forming each layer is as described above.
For example, when the first pressure-sensitive adhesive layer or the first intermediate layer is laminated on the first base material when manufacturing the first support sheet, the above-mentioned first pressure-sensitive adhesive composition or the above-mentioned first pressure-sensitive adhesive composition or The first pressure-sensitive adhesive layer or the first intermediate layer can be laminated by applying the composition for forming the first intermediate layer and drying it if necessary, or by irradiating with energy rays.

On the other hand, for example, when the thermosetting resin layer is further laminated on the first pressure-sensitive adhesive layer already laminated on the first base material, the composition for forming the thermosetting resin layer on the first pressure-sensitive adhesive layer. It is possible to directly form a thermosetting resin layer by coating an object. Similarly, when the first pressure-sensitive adhesive layer is further laminated on the first intermediate layer that has already been laminated on the first base material, the first pressure-sensitive adhesive composition is applied onto the first intermediate layer. , It is possible to directly form the first pressure-sensitive adhesive layer. As described above, when a continuous two-layer laminated structure is formed by using any of the compositions, the composition is further applied on the layer formed from the composition to form a new layer. It is possible to form. However, of these two layers, the layer to be laminated afterwards is formed in advance on another release film using the composition, and the side of the formed layer in contact with the release film is It is preferable to form a laminated structure of two continuous layers by laminating the exposed surface on the opposite side with the exposed surface of the remaining layers that have already been formed. At this time, it is preferable that the composition is applied to the peeled surface of the release film. The release film may be removed if necessary after the laminated structure is formed.

For example, a protective film forming sheet (the first support sheet is the first base material) in which the first pressure-sensitive adhesive layer is laminated on the first base material and the thermosetting resin layer is laminated on the first pressure-sensitive adhesive layer. And a sheet for forming a protective film, which is a laminate of the first pressure-sensitive adhesive layer), the first pressure-sensitive adhesive composition is applied onto the first base material and dried as necessary. A first pressure-sensitive adhesive layer is laminated on the first base material, a composition for forming a thermosetting resin layer is separately applied on the release film, and the composition is dried as necessary to form the release film. A thermosetting resin layer is formed, and the exposed surface of the thermosetting resin layer is bonded to the exposed surface of the first adhesive layer already laminated on the first base material to form a thermosetting resin layer. By laminating on the first pressure-sensitive adhesive layer, a protective film-forming sheet can be obtained.
Further, for example, in the case of producing a first support sheet in which the first intermediate layer is laminated on the first base material and the first pressure-sensitive adhesive layer is laminated on the first intermediate layer, the first base material is manufactured. The first intermediate layer is laminated on the first base material by applying the composition for forming the first intermediate layer on the first substrate and drying it as necessary, or by irradiating with energy rays. The first pressure-sensitive adhesive composition is applied onto the release film and dried as necessary to form the first pressure-sensitive adhesive layer on the release film, and the exposed surface of the first pressure-sensitive adhesive layer is formed. A first support sheet is obtained by laminating the first pressure-sensitive adhesive layer on the first intermediate layer by laminating it with the exposed surface of the first intermediate layer already laminated on the first base material. In this case, for example, a thermosetting resin layer forming composition is separately applied on the release film and dried if necessary to form a thermosetting resin layer on the release film. By laminating the exposed surface of the thermosetting resin layer with the exposed surface of the first pressure-sensitive adhesive layer already laminated on the first intermediate layer, and laminating the thermosetting resin layer on the first pressure-sensitive adhesive layer. , A sheet for forming a protective film can be obtained.

When the first pressure-sensitive adhesive layer or the first intermediate layer is laminated on the first base material, the composition for forming the first pressure-sensitive adhesive composition or the first intermediate layer is formed on the first base material as described above. Instead of the method of coating an object, a first pressure-sensitive adhesive composition or a composition for forming a first intermediate layer is applied on a release film, and if necessary, dried or irradiated with energy rays. By forming a first pressure-sensitive adhesive layer or a first intermediate layer on the release film and bonding the exposed surface of these layers to one surface of the first base material, the first pressure-sensitive adhesive layer or the first The intermediate layer may be laminated on the first base material.
In either method, the release film may be removed at an arbitrary timing after the desired laminated structure is formed.

As described above, all the layers other than the first base material constituting the protective film forming sheet can be laminated in advance by forming them on the release film and laminating them on the surface of the target layer, which is necessary. Depending on the situation, a layer that employs such a step may be appropriately selected to produce a protective film forming sheet.

The protective film forming sheet is usually stored in a state where a release film is attached to the surface of the outermost layer (for example, a thermosetting resin layer) on the opposite side of the first support sheet. Therefore, a composition for forming a layer constituting the outermost layer, such as a composition for forming a thermosetting resin layer, is applied onto the release film (preferably the release-treated surface thereof), and if necessary. By drying, a layer constituting the outermost layer is formed on the release film, and each of the remaining layers is placed on the exposed surface on the side opposite to the side in contact with the release film of this layer. A protective film-forming sheet can also be obtained by laminating by a method and leaving the release film in a bonded state without removing it.

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

The components used in the production of the composition for forming a thermosetting resin layer are shown below.
-Polymer component Polymer component (A) -1: 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). Resin (weight average molecular weight 800,000, glass transition temperature -28 ° C).
-Epoxy resin Epoxy resin (B1) -1: Liquid bisphenol F type epoxy resin ("YL983U" manufactured by Mitsubishi Chemical Corporation)
Epoxy resin (B1) -2: Polyfunctional aromatic epoxy resin ("EPPN-502H" manufactured by Nippon Kayaku Co., Ltd.)
Epoxy resin (B1) -3: Dicyclopentadiene type epoxy resin ("EPICLON HP-7200" manufactured by DIC Corporation)
-Thermosetting agent Thermosetting agent (B2) -1: Novolac type phenol resin ("BRG-556" manufactured by Showa Denko KK)
-Curing accelerator Curing accelerator (C) -1: 2-Phenyl-4,5-dihydroxymethylimidazole ("Curesol 2PHZ-PW" manufactured by Shikoku Chemicals Corporation)
-Filler Filler (D) -1: Spherical silica modified with an epoxy group ("Admanano YA050C-MKK" manufactured by Admatex)

[Manufacturing Example 1]
(Manufacturing of adhesive resin (I-2a))
An acrylic polymer was obtained by carrying out a polymerization reaction using -2-ethylhexyl acrylate (hereinafter abbreviated as "2EHA") (80 parts by mass) and HEA (20 parts by mass) as raw materials for the copolymer. ..
2-Methacryloyloxyethyl isocyanate (hereinafter abbreviated as "MOI") (22 parts by mass, about 80 mol% with respect to HEA) was added to this acrylic polymer, and the mixture was added in an air stream at 50 ° C. for 48 hours. By carrying out the reaction, the desired adhesive resin (I-2a) was obtained.

[Manufacturing Example 2]
(Manufacturing of adhesive resin (I-2a))
Butyl acrylate (hereinafter abbreviated as "BA") (52 parts by mass), methyl methacrylate (hereinafter abbreviated as "MMA") (20 parts by mass), HEA (28 parts by mass) are raw materials for the copolymer. As a result, an acrylic polymer was obtained by carrying out a polymerization reaction.
2-Methacryloyloxyethyl isocyanate (hereinafter abbreviated as "MOI") (28 parts by mass, about 90 mol% with respect to HEA) was added to this acrylic polymer, and the mixture was added in an air stream at 50 ° C. for 48 hours. By carrying out the reaction, the desired adhesive resin (I-2a) was obtained.

[Manufacturing Example 3]
(Manufacturing of adhesive resin (I-2a))
An acrylic polymer was obtained by carrying out a polymerization reaction using lauryl acrylate (hereinafter abbreviated as "LA") (80 parts by mass) and HEA (20 parts by mass) as raw materials for the copolymer.
MOI was added to this acrylic polymer so that the total number of moles of isocyanate groups in MOI was 0.8 times the total number of moles of hydroxyl groups in HEA, and at 50 ° C. in the air stream. The desired adhesive resin (I-2a) was obtained by carrying out the addition reaction for 48 hours.

[Manufacturing Example 4]
(Manufacturing of adhesive resin (I-2a))
Acrylic by carrying out a polymerization reaction using 2EHA (40 parts by mass), vinyl acetate (hereinafter, may be abbreviated as "VAc") (40 parts by mass) and HEA (20 parts by mass) as raw materials for the copolymer. A system polymer was obtained.
MOI was added to this acrylic polymer so that the total number of moles of isocyanate groups in MOI was 0.8 times the total number of moles of hydroxyl groups in HEA, and at 50 ° C. in the air stream. The desired adhesive resin (I-2a) was obtained by carrying out the addition reaction for 48 hours.

[Manufacturing Example 5]
(Manufacturing of adhesive resin (I-2a))
An acrylic polymer was obtained by carrying out a polymerization reaction using 2EHA (80 parts by mass) and HEA (20 parts by mass) as raw materials for the copolymer.
MOI was added to this acrylic polymer so that the total number of moles of isocyanate groups in MOI was 0.8 times the total number of moles of hydroxyl groups in HEA, and at 50 ° C. in the air stream. The desired adhesive resin (I-2a) was obtained by carrying out the addition reaction for 48 hours.

[Example 1]
<Manufacturing of protective film forming sheet>
(Manufacture of composition for forming a thermosetting resin layer)
Polymer component (A) -1 (100 parts by mass), epoxy resin (B1) -1 (135 parts by mass), epoxy resin (B1) -2 (90 parts by mass), epoxy resin (B1) -3 (150 parts by mass) Parts), curing accelerator (C) -1 (180 parts by mass), curing accelerator (G) -1 (1 part by mass), and filler (D) -1 (160 parts by mass) are dissolved in methyl ethyl ketone. Then, by stirring at 23 ° C., a resin layer forming composition (III-1) having a solid content concentration of 55% by mass was obtained as a thermosetting resin layer forming composition.

(Manufacturing of First Adhesive Composition)
To the adhesive resin (I-2a) (100 parts by mass) obtained in Production Example 1, a trimerizing isocyanate trimer addition of trimethylolpropane as an isocyanate-based cross-linking agent (“Coronate L” manufactured by Tosoh Corporation). ) (0.5 parts by mass) was added and stirred at 23 ° C. to obtain a first pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the first pressure-sensitive adhesive composition. .. The number of copies to be blended in this "manufacturing of the first pressure-sensitive adhesive composition" is a solid content conversion value.

(Manufacturing of protective film forming sheet)
The first pressure-sensitive adhesive composition obtained above is applied to the peeled surface of a peeled film (“SP-PET38131” manufactured by Lintec Corporation, thickness 38 μm) in which one side of a polyethylene terephthalate film is peeled by a silicone treatment. The first pressure-sensitive adhesive layer having a thickness of 30 μm was formed on the release film by heating and drying at 110 ° C. for 1 minute.
Next, on the exposed surface of the first pressure-sensitive adhesive layer, as the first base material, a polyolefin film (thickness 25 μm), an adhesive layer (thickness 2.5 μm), a polyethylene terephthalate film (thickness 50 μm), and an adhesive layer A first support sheet was obtained by laminating a laminated film having a thickness of 105 μm, which was formed by laminating (thickness 2.5 μm) and a polyolefin film (thickness 25 μm) in this order.

The composition for forming a thermosetting resin layer obtained above on the peeled surface of a peeled film (“SP-PET38131” manufactured by Lintec Corporation, thickness 38 μm) obtained by peeling one side of a polyethylene terephthalate film by silicone treatment. A thermosetting resin layer having a thickness of 40 μm was prepared by applying an object and drying it at 100 ° C. for 2 minutes.

Next, the release film is removed from the first pressure-sensitive adhesive layer of the first support sheet obtained above, and the exposed surface of the thermosetting resin layer obtained above is bonded to the exposed surface of the first pressure-sensitive adhesive layer. A protective film-forming sheet was obtained in which the first base material, the first 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]
(Manufacturing of First Adhesive Composition)
To the adhesive resin (I-2a) (100 parts by mass) obtained in Production Example 2, a trimerizing isocyanate trimer adduct of trimethylolpropane as an isocyanate-based cross-linking agent (“Coronate L” manufactured by Tosoh Corporation). ”) (1.0 part by mass) is added and stirred at 23 ° C. to obtain the first pressure-sensitive adhesive composition (I-2') having a solid content concentration of 30% by mass as the first pressure-sensitive adhesive composition. Obtained. The number of copies to be blended in this "manufacturing of the first pressure-sensitive adhesive composition" is a solid content conversion value.

(Manufacturing of protective film forming sheet)
A first support sheet was obtained in the same manner as in Example 1 except that the first pressure-sensitive adhesive composition described in Example 1 was changed to the first pressure-sensitive adhesive composition of Comparative Example 1 obtained above. It was.

The composition for forming a thermosetting resin layer obtained above on the peeled surface of a peeled film (“SP-PET38131” manufactured by Lintec Corporation, thickness 38 μm) obtained by peeling one side of a polyethylene terephthalate film by silicone treatment. A thermosetting resin layer having a thickness of 40 μm was prepared by applying an object and drying it at 100 ° C. for 2 minutes.

Next, the release film was removed from the first pressure-sensitive adhesive layer of the first support sheet obtained above, and the exposed surface of the first pressure-sensitive adhesive layer was covered with the same thermosetting resin layer as in Example 1 obtained above. The protective film forming sheet of Comparative Example 1 in which the first base material, the first pressure-sensitive adhesive layer, the thermosetting resin layer, and the release film are laminated in this order in the thickness direction of the exposed surfaces are bonded together. Obtained.

[Example 2]
(Manufacturing of First Adhesive Composition)
To the adhesive resin (I-2a) (100 parts by mass) obtained in Production Example 3, a trimerizing isocyanate trimer addition of trimethylolpropane as an isocyanate-based cross-linking agent (“Coronate L” manufactured by Tosoh Corporation). (1.0 parts by mass) is added and stirred at 23 ° C. to obtain a first pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the first pressure-sensitive adhesive composition. It was. The number of copies to be blended in this "manufacturing of the first pressure-sensitive adhesive composition" is a solid content conversion value.

(Manufacturing of protective film forming sheet)
The protective film of Example 2 is the same as that of Example 1, except that the first pressure-sensitive adhesive composition described in Example 1 is changed to the first pressure-sensitive adhesive composition of Example 2 obtained above. A forming sheet was obtained.

[Example 3]
(Manufacturing of First Adhesive Composition)
To the adhesive resin (I-2a) (100 parts by mass) obtained in Production Example 4, a trimerizing isocyanate trimer addition of trimethylolpropane as an isocyanate-based cross-linking agent (“Coronate L” manufactured by Tosoh Corporation). (1.0 parts by mass) is added and stirred at 23 ° C. to obtain a first pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the first pressure-sensitive adhesive composition. It was. The number of parts to be blended in this "manufacturing of the first pressure-sensitive adhesive composition" is a solid content conversion value.

(Manufacturing of protective film forming sheet)
The protective film of Example 3 is the same as that of Example 1, except that the first pressure-sensitive adhesive composition described in Example 1 is changed to the first pressure-sensitive adhesive composition of Example 3 obtained above. A forming sheet was obtained.

[Example 4]
(Manufacturing of First Adhesive Composition)
To the adhesive resin (I-2a) (100 parts by mass) obtained in Production Example 5, a trimerizing isocyanate trimer addition of trimethylolpropane as an isocyanate-based cross-linking agent (“Coronate L” manufactured by Tosoh Corporation). (1.0 parts by mass) is added and stirred at 23 ° C. to obtain a first pressure-sensitive adhesive composition (I-2) having a solid content concentration of 30% by mass as the first pressure-sensitive adhesive composition. It was. The number of parts to be blended in this "manufacturing of the first pressure-sensitive adhesive composition" is a solid content conversion value.

(Manufacturing of protective film forming sheet)
The protective film of Example 4 is the same as that of Example 1, except that the first pressure-sensitive adhesive composition described in Example 1 is changed to the first pressure-sensitive adhesive composition of Example 3 obtained above. A forming sheet was obtained.

<Evaluation of protective film forming sheet>
With respect to the thermosetting resin layer and the first pressure-sensitive adhesive layer obtained in Example 1 and Comparative Example 1, the contact angles of pure water, diiodomethane, and 1-bromonaphthalene were determined in an environment of a temperature of 23 ° C. and a humidity of 50%. from these, the dispersion force component gamma _s ^d, a polar component gamma _s ^p, determine the respective surface free energy of the hydrogen bond component gamma _s ^h, from each of the sum of each layer surface, the surface free energy gamma _s ^total I asked.
The results are shown in Table 1.
The difference between the γ _s ^total of the thermosetting resin layer and the γ _s ^total of the first pressure-sensitive adhesive layer in each of the protective film forming sheets of Example 1 and Comparative Example 1 is as shown in Table 1.
The difference between the contact angle of the thermosetting resin layer with water and the contact angle of the first pressure-sensitive adhesive layer with water in each of the protective film forming sheets of Example 1 and Comparative Example 1 is also shown in Table 1.

The first pressure-sensitive adhesive layers obtained in Examples 1 to 4 and Comparative Example 1 were subjected to a UV irradiation device (RAD-2000 m / 8 manufactured by Lintec) under the conditions of an illuminance of 230 mW / cm ² and a light intensity of 760 mJ / cm ² . After UV irradiation, the contact angles of pure water, diiodomethane, and 1-bromonaphthalene were determined in an environment of 23 ° C. and 50% humidity, and from these, the dispersion force component γ _s ^d , the polar component γ _s ^p , and the hydrogen bond component γ were obtained. It determined each surface free energy of _s ^h, from each of the sum of each layer surface to determine the surface free energy gamma _s ^total.
The results are shown in Table 2 together with the results of the uncured thermosetting resin layer.
The difference between the γ _s ^total of the thermosetting resin layer and the γ _s ^total of the first pressure-sensitive adhesive layer after UV curing in each of the protective film forming sheets of Example 1 and Comparative Example 1 is as shown in Table 2. is there.
Table 2 also shows the difference between the contact angle of the thermosetting resin layer with water and the contact angle of the first pressure-sensitive adhesive layer after UV curing with water in each of the protective film forming sheets of Example 1 and Comparative Example 1. It's a street.

<Evaluation of peelability after UV curing>
After preparing the protective film forming sheets of Examples 1 to 4 and Comparative Example 1, one week later, the peelability after UV curing was evaluated by the following procedure.
A protective film forming sheet was attached on the circuit surface of a 6-inch size bumped semiconductor wafer by heat lamination at 70 ° C.
After affixing, the temperature is returned to room temperature (about 5 minutes later), and then UV irradiation is performed with a UV irradiation device (RAD-2000 m / 8 manufactured by Lintec Corporation) under the conditions of an illuminance of 230 mW / cm ² and a light intensity of 760 mJ / cm ² . The first pressure-sensitive adhesive layer was cured. After that, when an attempt was made to peel off the first support sheet from the thermosetting resin layer, in the protective film forming sheets of Examples 1 to 4, the first support sheet composed of the first base material and the first adhesive layer was heated. Although it could be easily peeled off at the interface with the curable resin layer (peeling property "good"), in the protective film forming sheet of Comparative Example 1, the first pressure-sensitive adhesive layer adhered to the thermosetting resin layer. As it is, the first base material was peeled off, or the first pressure-sensitive adhesive layer partially coagulated and fractured and remained on the surface of the thermosetting resin layer (peeling property "poor").

Water thermoset difference between gamma _s ^total and the first pressure-sensitive adhesive layer after UV curing gamma _s ^total resin layer and the first pressure-sensitive adhesive layer after the contact angle and UV curing to water of the thermosetting resin layer Although there was no large difference in the contact angle with respect to the above, as shown in Table 2, the difference in the peelability between the first support sheet and the thermosetting resin layer appeared as a large difference. That is, the difference between the γ _s ^total of the thermosetting resin layer and the γ _s ^total of the first adhesive layer, not after UV curing but before UV curing, or the water of the thermosetting resin layer before UV curing. The difference between the contact angle with respect to water and the contact angle of the first pressure-sensitive adhesive layer with respect to water greatly affects the peelability between the first support sheet and the thermosetting resin layer.

In the protective film forming sheets of Examples 1 to 4 and Comparative Example 1, the polymer component (A) -1 containing butyl acrylate (BA) as a main component is used in the thermosetting resin layer. In the first pressure-sensitive adhesive layers 1 to 4, a pressure-sensitive adhesive resin (I-2a) containing -2-ethylhexyl acrylate (2EHA) or lauryl acrylate (LA) as a main component is used, so that the surface free energy can be increased. While the difference can be 10 mJ / m ² or more, in the first pressure-sensitive adhesive layer of Comparative Example 1, the pressure-sensitive adhesive containing butyl acrylate (BA) as a main component is the same as the thermosetting resin layer. Since the sex resin (I-2a) is used, the difference in surface free energy is small.

It is considered that it takes about one week for the protective film forming sheet to be produced and the quality such as adhesive strength to stabilize. Therefore, in 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 first support sheet is small, the components are transferred at the interface between the two and the adhesive strength is increased. It is probable that the temperature rose abnormally, resulting in poor peeling.
In the protective film forming sheet of Example 1, in which the difference between the surface free energy of the thermosetting resin layer and the surface free energy of the first support sheet is large, there is no migration of components at the interface between the two, and the adhesive force is stable. It is considered that the easy peelability of the interface between the first support sheet and the thermosetting resin layer has become excellent.

INDUSTRIAL APPLICABILITY The present invention can be used for manufacturing a semiconductor chip or the like having a bump on a connection pad portion used in a flip chip mounting method.

1, 2, 3 ... Protective film forming sheet, 11 ... 1st base material, 11 ... Thermosetting resin layer side surface of 11 ... 1st base material, 12 ... Curable resin layer, 12 '... 1st protective film, 13 ... 1st pressure-sensitive adhesive layer, 13a ... Surface of 1st pressure-sensitive adhesive layer, 14 ... 1st intermediate layer, 101, 102, 103 ... 1st Support sheet, 101a, 102a, 103a ... Surface of first support sheet, 90 ... Semiconductor wafer, 90a ... Circuit surface of semiconductor wafer, 91 ... Bump, 91a ... Surface of bump, 911・ ・ ・ The top of the bump

Claims (2)

A protective film forming sheet in which a thermosetting resin layer is laminated on the first adhesive layer of the first support sheet in which at least the first base material and the first adhesive layer are laminated.
The thermosetting resin layer is a layer for forming a protective film on the surface of a semiconductor wafer by attaching it to a surface having bumps and heat-curing it.
The difference between the surface free energy of the thermosetting resin layer on the surface of the first support sheet side before heat curing and the surface free energy of the surface of the first adhesive layer on the surface of the thermosetting resin layer is 10 mJ / m. A sheet for forming a protective film, which is characterized by having m ² or more. The difference between the contact angle of the surface of the thermosetting resin layer on the side of the first support sheet with water before heat curing and the contact angle of the surface of the first adhesive layer on the surface of the thermosetting resin layer with water is 30. The protective film forming sheet according to claim 1, which is at least ° °.

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