KR102263936B1 - Pressure-Sensitive Adhesive Sheet - Google Patents

Abstract

The present invention provides a pressure-sensitive adhesive sheet that has suitable adhesion to a sealing resin and a semiconductor chip constituting a semiconductor package, can be easily peeled from the sealing resin and a semiconductor chip, and can prevent adhesive residue during peeling In order to do so, the pressure-sensitive adhesive sheet of the present invention is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer, and the contact angle of the pressure-sensitive adhesive layer surface to 4-tert-butylphenyl glycidyl ether is 15° or more, and 23° C. of the pressure-sensitive adhesive sheet The adhesive force with respect to the polyethylene terephthalate in is 0.5 N/20 mm or more.

Description

Adhesive Sheet {Pressure-Sensitive Adhesive Sheet}

The present invention relates to an adhesive sheet.

BACKGROUND ART In recent years, when miniaturization of a semiconductor device is required, as a semiconductor packaging technology, a chip size/scale package (CSP) for forming a semiconductor package having the same size as that of an embedded semiconductor device is attracting attention. Among CSPs, a Wafer Level Package (WLP) is known as a semiconductor packaging technology for forming a particularly compact and highly integrated package. WLP is a technique in which a plurality of semiconductor chips are collectively sealed with a sealing resin without using a substrate, and then the individual semiconductor chips are cut and separated to obtain a semiconductor package. In general, when semiconductor chips are collectively sealed, in order to prevent movement of the semiconductor chips, a plurality of semiconductor chips are temporarily fixed with a predetermined temporary fixing material, and the plurality of semiconductor chips are collectively sealed on the temporary fixing material. After that, when cutting and separating into individual semiconductor chips (after bulk sealing, before cutting separation, or after cutting separation), the temporary fixing material is peeled from the structure including the sealing resin and the semiconductor chip. As a temporary fixing material used in this way, a low-adhesive adhesive sheet is often used.

However, when the conventional pressure-sensitive adhesive sheet is used, there is a problem that the adhesive remains in the structure when it is peeled off from the structure including the sealing resin and the semiconductor chip. In particular, there exists a problem that adhesive residue in the peripheral part of a semiconductor chip becomes remarkable, and the said adhesive residue becomes a cause of a manufacturing efficiency fall.

Japanese Patent Laid-Open No. 2001-308116 Japanese Patent Laid-Open No. 2001-313350

The present invention has been made in order to solve the above conventional problems, and the object thereof is that it has suitable adhesiveness to the sealing resin and semiconductor chip constituting the semiconductor package, and can be easily peeled from the sealing resin and the semiconductor chip. Moreover, it is providing the adhesive sheet which does not generate|occur|produce easily the adhesive residue at the time of peeling.

The adhesive sheet of this invention is an adhesive sheet provided with an adhesive layer, the contact angle with respect to 4-tert- butylphenyl glycidyl ether of the said adhesive layer surface is 15 degrees or more, The polyethylene in 23 degreeC of the said adhesive sheet Adhesion to terephthalate is 0.5N/20mm or more.

In one embodiment, the sp value of the material which comprises the adhesive in the said adhesive layer is 7 (cal/cm<3>) ^1/2 - 10 (cal/cm<3>) ^1/2 .

In one embodiment, the probe tack value of the said adhesive layer is 50 N/5 mmphi or more.

In one embodiment, the said adhesive layer contains an acrylic adhesive.

In one embodiment, the said acrylic adhesive contains the acrylic polymer which has a C4 or more alkylester in a side chain as a base polymer.

In one embodiment, in the said acrylic polymer, the content rate of the structural unit which has a C4 or more alkylester in a side chain is 30 weight% or more with respect to all the structural units which comprise the said acrylic polymer.

In one embodiment, the said adhesive layer contains a rubber-type adhesive.

In one embodiment, the said adhesive layer contains a silicone adhesive.

In one embodiment, the silicone pressure-sensitive adhesive includes, as a base polymer, a silicone rubber and a silicone resin, and the weight ratio (rubber:resin) of the silicone rubber to the silicone resin is 100:0 to 100:220.

In one embodiment, the said adhesive layer further contains thermally expansible microsphere.

In one embodiment, before heating the said thermally expansible microsphere, arithmetic surface roughness Ra of the said adhesive layer is 500 nm or less.

In one embodiment, the adhesive sheet of this invention joins the said adhesive layer outer surface whole surface to a bakelite plate under an environmental temperature of 23 degreeC, and is aged for 30 minutes under an environmental temperature of 40 degreeC, After that, 1.96 When hold|maintained for 2 hours, applying a load of N, the shift|offset|difference with respect to the said bakelite plate is 0.5 mm or less.

In one embodiment, the adhesive sheet of this invention is further equipped with a base material layer, The said adhesive layer is arrange|positioned on one side or both sides of the said base material layer.

In one embodiment, anchoring force of the said base material layer and the said adhesive layer is 6.0 N/19 mm or more.

According to the present invention, by providing the pressure-sensitive adhesive layer having a contact angle of 15° or more with respect to 4-tert-butylphenylglycidyl ether, it has suitable adhesion to the sealing resin and semiconductor chips constituting the semiconductor package, and the sealing resin and the semiconductor It is possible to obtain a pressure-sensitive adhesive sheet that can be easily peeled off from the chip and hardly causes adhesive residue during peeling.

Fig. 1 (a) is a view for explaining an example of using the conventional pressure-sensitive adhesive sheet for manufacturing a semiconductor package, (b) is for explaining an example of using the pressure-sensitive adhesive sheet of the present invention for manufacturing a semiconductor package drawing to do.
2 (a) and (b) are schematic cross-sectional views of the pressure-sensitive adhesive sheet according to one embodiment of the present invention.
3 is a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention.

A. Overview of the adhesive sheet

The adhesive sheet of this invention is equipped with an adhesive layer. The adhesive sheet of this invention may be comprised only with the said adhesive layer, and may further be equipped with arbitrary appropriate layers other than the said adhesive layer. As a layer other than an adhesive layer, the separator arrange|positioned so that peeling is possible on the base material layer which can function as a support body, and an adhesive layer, etc. are mentioned, for example. Moreover, you may be further equipped with another adhesive layer other than the said adhesive layer. A well-known structure may be sufficient as another adhesive layer.

As for the adhesive sheet of this invention, the adhesive force with respect to the polyethylene terephthalate in 23 degreeC becomes like this. Preferably it is 0.5N/20mm or more, More preferably, they are 0.5N/20mm - 20N/20mm, More preferably is 0.5N/20mm to 15N/20mm. In one embodiment, the adhesive force of the adhesive layer of the adhesive sheet of this invention falls by a heating or light irradiation. In this case, the said adhesive force before reducing adhesive force is 2.5N/20mm - 20N/20mm. In addition, in this specification, "adhesive force with respect to polyethylene terephthalate" refers to a polyethylene terephthalate film (thickness 25 µm) bonded to an adhesive sheet (a pressure-sensitive adhesive layer having a width of 20 mm x a length of 100 mm (bonding conditions: 2 kg) Roller 1 reciprocating), after standing for 30 minutes under an environmental temperature of 23° C., the sample is subjected to a tensile test (peel rate: 300 mm/min, peel angle 180°) and refers to the adhesive force measured.

The adhesive force of the adhesive sheet of this invention with respect to a silicon wafer (thickness 500 micrometers) at 23 degreeC becomes like this. Preferably they are 0.1N/20mm - 4N/20mm, More preferably, they are 0.15N/20mm - 3N/20mm and more preferably 0.2N/20mm to 2/20mm. If it is such a range, the adhesive sheet with which the adhesive force with respect to a semiconductor chip and peelability were compatible can be obtained. The adhesive force to a silicon wafer can also be measured by the method similar to the said "adhesive force to polyethylene terephthalate".

The adhesive force of the adhesive sheet of the present invention to the epoxy resin sheet at 23° C. is preferably 0.1 N/20 mm to 5 N/20 mm, more preferably 0.3 N/20 mm to 4 N/20 mm, further Preferably it is 0.5N/20mm - 3/20mm. If it is such a range, adhesive residual at the time of peeling from sealing resin (it mentions later in detail) can be suppressed. The adhesive force with respect to an epoxy resin film can also be measured by the method similar to the said "adhesive force with respect to polyethylene terephthalate." In addition, as the said epoxy resin film, the film comprised with the sealing resin demonstrated in evaluation of "stand-off suppression effect" of an Example, for example can be used.

The entire outer surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet (width 10 mm × length 150 mm) of the present invention is bonded to a bakelite plate (width 10 mm × length 125 mm) under an environmental temperature of 23°C, and 30°C under an environmental temperature of 40°C When it is aged for minutes and then held for 2 hours while applying a load of 1.96 N, the deviation of the pressure-sensitive adhesive sheet with respect to the bakelite plate is preferably 0.5 mm or less, and more preferably 0.4 mm or less. In addition, here, "difference|difference of the adhesive sheet with respect to the bakelite plate" means the amount of movement of the adhesive sheet from the said initial state on the basis of the state (initial state) before the said aging. The said adhesive sheet with a small shift|offset|difference amount is an adhesive sheet in which the cohesive failure of an adhesive layer does not generate|occur|produce easily, and this adhesive sheet is essentially an adhesive sheet in which an adhesive does not easily remain. If it is such an adhesive sheet, the effect of this invention becomes remarkable. The pressure-sensitive adhesive layer in which cohesive failure does not easily occur can be formed, for example, by using the above-mentioned acrylic pressure-sensitive adhesive (preferably an pressure-sensitive adhesive containing a crosslinked acrylic polymer as a base polymer) as the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer. In addition, a rubber-based pressure-sensitive adhesive is used as the pressure-sensitive adhesive, and more specifically, a rubber-based pressure-sensitive adhesive comprising a base polymer (rubber) constituting the rubber-based pressure-sensitive adhesive, a hydroxyl group-containing polyolefin, and a crosslinking agent capable of reacting with the hydroxyl group of the hydroxyl group polyolefin (Rub1) ), by appropriately adjusting the blending amounts of the hydroxyl group-containing polyolefin and the crosslinking agent, a pressure-sensitive adhesive layer in which cohesive failure is unlikely to occur can be formed. Details will be described later.

The thickness of the adhesive sheet of this invention becomes like this. Preferably they are 3 micrometers - 300 micrometers, More preferably, they are 5 micrometers - 150 micrometers, More preferably, they are 10 micrometers - 100 micrometers.

B. adhesive layer

The pressure-sensitive adhesive layer has a contact angle with respect to 4-tert-butylphenyl glycidyl ether on the surface of 15° or more, more preferably 20° or more, still more preferably 30° to 100°, Particularly preferably, it is 40° to 60°.

The affinity for the adhesive layer of the adhesive sheet of this invention with respect to the monomer component which comprises the sealing resin (for example, epoxy resin) used when sealing a semiconductor chip, and the said sealing resin is adjusted. Specifically, the said adhesive layer is adjusted so that the said affinity may become low in the range which can express moderate adhesiveness with respect to sealing resin (and a semiconductor chip). The contact angle with respect to 4-tert- butylphenyl glycidyl ether shows the said range of the adhesive layer whose affinity was adjusted suitably. By adjusting the affinity for the sealing resin and the monomer components constituting the sealing resin in this way, the adhesive residue is less, more specifically, a structure comprising a semiconductor and a resin (or precursor monomer of the resin) for sealing the semiconductor When it adhere|attaches to (FIG. 1) and peels after that, the adhesive sheet which can reduce the adhesive layer component adhering to the said structure can be obtained. The mechanism that adhesive residue is reduced by use of the adhesive sheet of this invention is considered as follows.

Fig. 1(a) shows an example in the case of using the conventional adhesive sheet 10' for manufacture of a semiconductor package. The pressure-sensitive adhesive sheet 10' has a pressure-sensitive adhesive layer, and the outer surface of the pressure-sensitive adhesive layer serves as an adhesive surface. Conventionally, in manufacturing the semiconductor package CSP, first, the semiconductor chip 1 is adhere|attached on the adhesive sheet 10' (a-i). Thereafter, the semiconductor chip 1 is sealed so as to be coated with a composition (2') containing a monomer serving as a precursor of the sealing resin (2) (a-ii), and then the composition (2') is applied Cure (a-iii). Moreover, as said composition, the composition containing a naphthalene type bifunctional epoxy resin (epoxy equivalent: 144) is used, for example. Subsequently, from the structure 20 including the semiconductor chip 1 and the encapsulating resin 2, before or after cutting and separating the semiconductor chips individually (in the example shown, before cutting and separating), The adhesive sheet 10' is peeled off (a-iv). When the conventional adhesive sheet is used, adhesive residue is easy to generate|occur|produce at the time of peeling. In particular, in the peripheral part of the semiconductor chip 1, adhesive residue is seen remarkably. The inventors of the present invention, when the conventional pressure-sensitive adhesive sheet 10' is used, the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet 10' at the time of peeling is raised so as to surround the bottom of the semiconductor chip 1, and the pressure-sensitive adhesive sheet at the time of peeling It was discovered that the level|step difference (henceforth a stand-off) resulting from the base of the semiconductor chip 1 generate|occur|produced in the adhesive layer of (10'). When the stress derived from the semiconductor chip 1 concentrates on the said stand-off part, cohesive failure of an adhesive layer generate|occur|produces, As a result, it is thought that the said adhesive residue generate|occur|produces.

FIG.1(b) shows an example in the case of using the adhesive sheet 10 of this invention for manufacture of a semiconductor package. The pressure-sensitive adhesive sheet 10 has a pressure-sensitive adhesive layer, and the outer surface of the pressure-sensitive adhesive layer serves as an adhesive surface. In Fig. 1 (b), the semiconductor chip 1 and the sealing resin ( The structure 20 containing 2) is formed, and the adhesive sheet 10 is peeled after that. When the adhesive sheet 10 of this invention is used, the standoff which generate|occur|produces in the adhesive sheet 10 is very small (or does not generate|occur|produce), and adhesive residue is suppressed.

In the conventional adhesive sheet 10', the adhesive layer component migrates to the composition or sealing resin containing the monomer used as the precursor of the sealing resin 2, As a result, the resin layer of the adhesive sheet 10'. It is thought that it rises so as to surround the bottom of the semiconductor chip 1 and that a standoff occurs. In addition, the presence or absence of component migration can be confirmed by the spectral analysis by FT-IR etc. On the other hand, in this invention, since affinity with respect to the sealing resin used when an adhesive layer seals a semiconductor chip, and the monomer component which comprises the said sealing resin is adjusted, the above-mentioned component migration is suppressed and stand-off becomes very small (or does not occur), and as a result, it is thought that adhesive residue is suppressed. Hereinafter, in this specification, the sealing resin used when sealing a semiconductor chip, and the monomer component which comprises the said sealing resin are collectively called a sealing material.

The said adhesive layer contains an adhesive. The sp value of the material (polymer) constituting the pressure-sensitive adhesive is preferably 7 (cal/cm 3 ) ^1/2 to 10 (cal/cm 3 ) ^1/2 , more preferably 7 (cal/cm 3 ) ^1/2 to 9.1 (cal/cm 3 ) ^1/2 , and more preferably 7 (cal/cm 3 ) ^1/2 to 8 (cal/cm 3 ) ^1/2 . If it is such a range, it can form the adhesive layer which has moderate adhesiveness, affinity with a sealing material is low and a standoff is hard to generate|occur|produce. The adhesive sheet provided with such an adhesive layer is hard to generate|occur|produce adhesive residue. In addition, the material constituting the pressure-sensitive adhesive as used herein means a polymer contained in the pressure-sensitive adhesive, such as a base polymer (base polymer after crosslinking in the case of crosslinking), rubber (rubber after crosslinking in the case of crosslinking), and a tackifier. . In the present invention, it is preferable that the sp value of at least the base polymer (base polymer after crosslinking in the case of crosslinking) or rubber (rubber after crosslinking in the case of crosslinking) which is the main component of the pressure-sensitive adhesive is within the above range.

In one embodiment, 1,3-bis(N,N-diclicidylaminomethyl)cyclohexane is brought into contact with the pressure-sensitive adhesive layer surface and placed in an environment of 50° C. for 2 hours, the pressure-sensitive adhesive surface is When the absorbance of the glycidyl group-derived peak is measured by FT-IR measurement, the absorbance ratio of the glycidyl group-derived peak is preferably 1.3 or less with respect to the absorbance of the glycidyl group-derived peak of the initial pressure-sensitive adhesive layer. , More preferably, it is 1.1 or less, More preferably, it is 1.05 or less. In addition, an "initial stage adhesive layer" means the adhesive layer before making 1, 3-bis (N, N- diglycidyl aminomethyl) cyclohexane contact. In another embodiment, 1,3-bis(N,N-diclicidylaminomethyl)cyclohexane is brought into contact with the surface of the pressure-sensitive adhesive layer, placed in an environment of 50° C. for 2 hours, and FT- on the surface of the pressure-sensitive adhesive layer When IR measurement (e.g., attenuated total reflection method (ATR method)) is performed, the amount of increase from the initial pressure-sensitive adhesive layer with respect to the absorbance at ^{the wave number (in the vicinity of 850 cm -1 ) at which the glycidyl group-derived peak occurs is,} Preferably it is 0.3 or less, More preferably, it is 0.1 or less. Here, 1,3-bis(N,N-diclicidylaminomethyl)cyclohexane is an epoxy compound which can become a material of resin which seals a semiconductor chip. Even when the epoxy compound is brought into contact with the adhesive layer, if the adhesive layer is not easily transferred as described above, a pressure-sensitive adhesive sheet with little adhesive residue can be obtained because stand-off is unlikely to occur even when used in the manufacture of a semiconductor package.

The thickness of the pressure-sensitive adhesive layer is preferably 1 μm to 300 μm, more preferably 3 μm to 300 μm, still more preferably 5 μm to 150 μm, still more preferably 10 μm to 100 μm, More preferably, it is 10 micrometers - 50 micrometers. As will be described later, when the pressure-sensitive adhesive layer contains thermally expansible microspheres, the thickness of the pressure-sensitive adhesive layer is preferably 3 µm to 300 µm, more preferably 5 µm to 150 µm, and 10 µm to 100 µm. more preferably. In such a range, an adhesive layer having excellent surface smoothness and excellent adhesion can be formed. When an adhesive layer does not contain thermally expansible microsphere, it is preferable that the thickness of an adhesive layer is 50 micrometers or less, It is more preferable that they are 1 micrometer - 50 micrometers, It is more preferable that they are 5 micrometers - 30 micrometers.

The elastic modulus by the nanoindentation method in 25 degreeC of the said adhesive layer becomes like this. Preferably it is less than 100 Mpa, More preferably, it is 0.1 Mpa - 50 Mpa, More preferably, it is 0.1 Mpa - 10 Mpa. If it is within this range, it is possible to obtain a pressure-sensitive adhesive sheet having an appropriate adhesive strength as a pressure-sensitive adhesive sheet that can be used for manufacturing a semiconductor package. The elastic modulus by the nanoindentation method is obtained from the applied load-indentation depth curve obtained by continuously measuring the applied load and the indentation depth to the indenter during loading and unloading when the indenter is pressed into the sample. refers to the modulus of elasticity. In the present specification, the elastic modulus by the nanoindentation method refers to the elastic modulus measured as described above under measurement conditions: load: 1 mN, load/unload speed: 0.1 mN/s, and holding time: 1 s.

The tensile modulus of elasticity in 25 degreeC of the said adhesive layer becomes like this. Preferably it is less than 100 Mpa, More preferably, it is 0.1 Mpa - 50 Mpa, More preferably, it is 0.1 Mpa - 10 Mpa. If it is within this range, it is possible to obtain a pressure-sensitive adhesive sheet having an appropriate adhesive strength as a pressure-sensitive adhesive sheet that can be used for manufacturing a semiconductor package. In addition, tensile elasticity modulus can be measured according to JISK7161:2008.

The probe tack value of the said adhesive layer becomes like this. Preferably it is 50N/5mmphi or more, More preferably, it is 75N/5mmphi or more, More preferably, it is 100N/5mmphi or more. Within this range, the retention of the adherend is excellent, and, for example, when the semiconductor chip is temporarily fixed, unnecessary displacement of the semiconductor chip can be prevented. The measuring method of a probe tack value is mentioned later.

<Adhesive>

As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, any appropriate pressure-sensitive adhesive may be used as long as the effect of the present invention is obtained. Preferably, a pressure-sensitive adhesive comprising a base polymer having an sp value in the above range is used. As said adhesive, an acrylic adhesive, a rubber-type adhesive, silicone adhesive etc. are mentioned, for example. Among them, an acrylic pressure-sensitive adhesive can be preferably used. Moreover, you may use an active energy ray hardening-type adhesive as an adhesive.

(Acrylic adhesive)

As said acrylic adhesive, the acrylic adhesive etc. which use as a base polymer the acrylic polymer (homopolymer or copolymer) using 1 type, or 2 or more types of (meth)acrylic acid alkylester as a monomer component are mentioned, for example.

The acrylic polymer preferably has, as a side chain, an alkyl ester having 4 or more carbon atoms, more preferably an alkyl ester having 6 or more carbon atoms, still more preferably an alkyl ester having 8 or more carbon atoms, and has 8 to carbon atoms. It is particularly preferred to have an alkylester having 20 carbon atoms, and most preferred to have an alkylester having 8 to 18 carbon atoms. When the acrylic polymer having a long side chain is used, a pressure-sensitive adhesive layer having low affinity with the sealing material can be formed. In the acrylic polymer, the content of the structural unit having an alkylester having 4 or more carbon atoms as a side chain is preferably 30% by weight or more, more preferably 50% by weight, based on all the structural units constituting the acrylic polymer. % or more, more preferably 70% by weight to 100% by weight, and particularly preferably 80% by weight to 100% by weight. If it is such a range, the adhesive layer with low affinity with a sealing material can be formed.

The acrylic pressure-sensitive adhesive may include a plurality of acrylic polymers, but the content of the acrylic polymer having an alkylester having 4 or more carbon atoms in the side chain is preferably 30 parts by weight to 100 parts by weight of the total acrylic polymer. It is 100 weight part, More preferably, it is 70 weight part - 100 weight part.

Specific examples of the (meth)acrylic acid alkyl ester include (meth) methyl acrylate, (meth) ethyl acrylate, (meth) acrylic acid propyl, (meth) acrylic acid isopropyl, (meth) acrylate butyl, (meth) acrylate isobutyl, ( s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylate ) Acrylic acid isooctyl, (meth)acrylic acid nonyl, (meth)acrylic acid isononyl, (meth)acrylic acid decyl, (meth)acrylic acid isodecyl, (meth)acrylic acid undecyl, (meth)acrylic acid dodecyl, (meth)acrylic acid tri Decyl, (meth)acrylic acid tetradecyl, (meth)acrylic acid pentadecyl, (meth)acrylic acid hexadecyl, (meth)acrylic acid heptadecyl, (meth)acrylic acid octadecyl, (meth)acrylic acid nonadecyl, (meth)acrylic acid eicosyl (meth)acrylic acid C1-20 alkylesters, such as these are mentioned. Among them, preferably, it is a (meth)acrylic acid alkyl ester having a linear or branched alkyl group having 4 to 20 carbon atoms (more preferably 6 to 20), particularly preferably 8 to 18), and more preferably is (meth)acrylic acid 2-ethylhexyl.

The said acrylic polymer may contain the unit corresponding to the other monomer component copolymerizable with the said (meth)acrylic-acid alkylester as needed for the purpose of modification, such as cohesion force, heat resistance, crosslinking property. As such a monomer component, For example, carboxyl group-containing monomers, such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, a maleic acid, a fumaric acid, a crotonic acid; acid anhydride monomers such as maleic anhydride and itaconic anhydride; (meth)acrylic acid hydroxyethyl, (meth)acrylic acid hydroxypropyl, (meth)acrylic acid hydroxybutyl, (meth)acrylic acid hydroxyhexyl, (meth)acrylic acid hydroxyoctyl, (meth)acrylic acid hydroxydecyl, (meth)acrylic acid ) hydroxyl group-containing monomers such as acrylic acid hydroxylauryl and (4-hydroxymethylcyclohexyl)methyl methacrylate; Contains sulfonic acid groups such as styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid monomer; (N) such as (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-butyl (meth)acrylamide, N-methylol (meth)acrylamide, and N-methylolpropane (meth)acrylamide -substituted) amide-based monomers; (meth)acrylic acid aminoalkyl monomers such as (meth)acrylic acid aminoethyl, (meth)acrylic acid N,N-dimethylaminoethyl, and (meth)acrylic acid t-butylaminoethyl; (meth)acrylic acid alkoxyalkyl monomers such as (meth)acrylic acid methoxyethyl and (meth)acrylic acid ethoxyethyl; maleimide-based monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, and N-phenylmaleimide; N-methylitaconimide, N-ethyl itaconimide, N-butyl itaconimide, N-octyl itaconimide, N-2-ethylhexyl itaconimide, N-cyclohexyl itaconimide itaconimide-based monomers such as mide and N-lauryl itaconimide; N-(meth)acryloyloxymethylenesuccinimide, N-(meth)acryloyl-6-oxyhexamethylenesuccinimide, N-(meth)acryloyl-8-oxyoctamethylenesuccinimide, etc. of succinimide-based monomers; Vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinyl vinyl-based monomers such as morpholine, N-vinylcarboxylic acid amides, styrene, α-methylstyrene, and N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; Epoxy group-containing acrylic monomers, such as (meth)acrylic-acid glycidyl; glycol-based acrylic ester monomers such as (meth)acrylic acid polyethylene glycol, (meth)acrylic acid polypropylene glycol, (meth)acrylic acid methoxyethylene glycol, and (meth)acrylic acid methoxypolypropylene glycol; (meth)acrylic acid tetrahydrofurfuryl, fluorine (meth)acrylate, acrylic acid ester monomers having a heterocyclic ring, such as silicone (meth)acrylate, a halogen atom, a silicon atom; Hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentylglycol di(meth)acrylate, pentaerythritol di(meth) Polyfunctionality such as acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy acrylate, polyester acrylate, urethane acrylate monomer; olefinic monomers such as isoprene, butadiene, and isobutylene; Vinyl ether type monomers, such as vinyl ether, etc. are mentioned. You may use these monomer components individually or in combination of 2 or more types. Among the above, more preferably, a carboxyl group-containing monomer (especially preferably acrylic acid) or a hydroxyl group-containing monomer (particularly preferably hydroxyethyl (meth)acrylate) is used. The content of the structural unit derived from the carboxyl group-containing monomer is preferably 0.1% by weight to 10% by weight, more preferably 0.5% by weight to 5% by weight, particularly preferably with respect to all the structural units constituting the acrylic polymer. is 1 wt% to 4 wt%. In addition, the content of the structural unit derived from the hydroxyl group-containing monomer is preferably 0.1 wt% to 20 wt%, more preferably 0.5 wt% to 10 wt%, based on all the constitutional units constituting the acrylic polymer. , particularly preferably 1% by weight to 7% by weight.

The acrylic pressure-sensitive adhesive may include any appropriate additives, if necessary. Examples of the additive include a crosslinking agent, a tackifier, a plasticizer (for example, a trimellitic acid ester plasticizer, a pyromellitic acid ester plasticizer, etc.), a pigment, a dye, a filler, an anti-aging agent, a conductive material, an antistatic agent, A ultraviolet absorber, a light stabilizer, a peeling regulator, a softener, surfactant, a flame retardant, antioxidant, etc. are mentioned.

Examples of the crosslinking agent contained in the acrylic pressure-sensitive adhesive include isocyanate-based crosslinking agent, epoxy-based crosslinking agent, melamine-based crosslinking agent, peroxide-based crosslinking agent, urea-based crosslinking agent, metal alkoxide-based crosslinking agent, metal chelate-based crosslinking agent, metal salt-based crosslinking agent, carbodiimide a crosslinking agent, an oxazoline crosslinking agent, an aziridine crosslinking agent, an amine crosslinking agent, and the like. Especially, an isocyanate type crosslinking agent or an epoxy type crosslinking agent is preferable.

Specific examples of the isocyanate-based crosslinking agent contained in the acrylic pressure-sensitive adhesive include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate; aromatic isocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and xylylene isocyanate; Trimethylolpropane/tolylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Kogyo Co., Ltd., trade name "Coronate L"), trimethylolpropane/hexamethylene diisocyanate trimer adduct (Nippon Polyurethane Co., Ltd. make, trade name "Coronate HL") ') and isocyanate adducts such as an isocyanurate form of hexamethylene diisocyanate (manufactured by Nippon Polyurethane Kogyo Co., Ltd., trade name "Coronate HX"); and the like. The content of the isocyanate-based crosslinking agent may be set to any suitable amount depending on the desired adhesive strength, and is typically 0.1 to 20 parts by weight, more preferably 0.5 to 20 parts by weight, based on 100 parts by weight of the base polymer. 10 parts by weight.

As the epoxy-based crosslinking agent contained in the acrylic pressure-sensitive adhesive, for example, N,N,N',N'-tetraglycidyl-m-xylenediamine, diglycidylaniline, 1,3-bis(N,N) -Glycidylaminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical, trade name "Tetrad C"), 1,6-hexanediol diglycidyl ether (manufactured by Kyoesha Chemical, trade name "Epolite 1600") , neopentyl glycol diglycidyl ether (manufactured by Kyoesha Chemical, trade name "Epolite 1500NP"), ethylene glycol diglycidyl ether (manufactured by Kyoesha Chemical, trade name "Epolite 40E"), propylene glycol Diglycidyl ether (manufactured by Kyoesha Chemical, trade name "Epolite 70P"), polyethylene glycol diglycidyl ether (manufactured by Nippon Yushi Corporation, trade name "Epiol E-400"), polypropylene glycol diglycidyl Ether (manufactured by Nippon Yushi, trade name "Epiol P-200"), sorbitol polyglycidyl ether (manufactured by Nagase Chemtex, trade name "Denacol EX-611"), glycerol polyglycidyl ether (manufactured by Nagase Chemtex, Inc., brand name "Denacol EX-314"), pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether (manufactured by Nagase Chemtex, brand name "Denacol EX-512"), sorbitan polyglycidyl ether, Trimethylolpropane polyglycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris(2-hydroxyethyl)isocyanurate, resorcinol diglycidyl Ether, bisphenol-S-diglycidyl ether, the epoxy resin etc. which have 2 or more epoxy groups in a molecule|numerator are mentioned. The content of the epoxy-based crosslinking agent may be set to any suitable amount depending on the desired adhesive strength, and is typically 0.01 to 10 parts by weight, more preferably 0.03 to 10 parts by weight, based on 100 parts by weight of the base polymer. 5 parts by weight.

As said tackifier contained in the said acrylic adhesive, arbitrary appropriate tackifiers are used. As a tackifier, tackifying resin is used, for example. Specific examples of the tackifying resin include rosin tackifying resins (eg, unmodified rosin, modified rosin, rosin phenolic resin, rosin ester-based resin, etc.), terpene-based tackifying resin (eg, terpene-based resin). , terpene phenol-based resin, styrene-modified terpene-based resin, aromatic modified terpene-based resin, hydrogenated terpene-based resin), hydrocarbon-based tackifying resin (eg, aliphatic hydrocarbon resin, aliphatic cyclic hydrocarbon resin, aromatic hydrocarbon resin) (For example, styrene-based resins, xylene-based resins, etc.), aliphatic/aromatic petroleum resins, aliphatic/alicyclic petroleum resins, hydrogenated hydrocarbon resins, coumarone-based resins, coumaron-indene-based resins, etc.), phenolic tackifying resins (For example, alkylphenol-based resin, xyleneformaldehyde-based resin, resol, novolac, etc.), ketone-based tackifying resin, polyamide-based tackifying resin, epoxy-based tackifying resin, elastomer-based tackifying resin, etc. can Among them, rosin-based tackifying resin, terpene-based tackifying resin, or hydrocarbon-based tackifying resin (such as styrene-based resin) is preferable. You may use a tackifier individually or in combination of 2 or more types. To [ the addition amount of the said tackifier / 100 weight part of base polymers ], Preferably they are 5 weight part - 100 weight part, More preferably, they are 10 weight part - 50 weight part.

Preferably, as the tackifying resin, a resin having a high softening point or glass transition temperature (Tg) is used. When a resin with a high softening point or glass transition temperature (Tg) is used, a pressure-sensitive adhesive layer capable of exhibiting high tackiness is formed even in a high-temperature environment (for example, in a high-temperature environment in processing at the time of semiconductor chip sealing). can do. The softening point of the tackifier is preferably 100°C to 180°C, more preferably 110°C to 180°C, still more preferably 120°C to 180°C. The glass potential temperature (Tg) of the tackifier is preferably 100°C to 180°C, more preferably 110°C to 180°C, still more preferably 120°C to 180°C.

Preferably, low-polarity tackifying resin is used as said tackifying resin. When low-polarity tackifying resin is used, the adhesive layer with low affinity with a sealing material can be formed. As low-polarity tackifying resin, For example, aliphatic hydrocarbon resin, aliphatic cyclic hydrocarbon resin, aromatic hydrocarbon resin (For example, styrene resin, xylene-type resin, etc.), aliphatic / aromatic petroleum resin, aliphatic - Hydrocarbon type tackifying resin per alicyclic type petroleum resin and hydrogenated hydrocarbon resin is mentioned. Especially, Preferably, it is a C5-C9 tackifier. This is because such a tackifier can form a pressure-sensitive adhesive layer having low polarity, excellent compatibility with an acrylic polymer, no phase separation in a wide temperature range, and excellent stability.

The acid value of the said tackifying resin becomes like this. Preferably it is 40 or less, More preferably, it is 20 or less, More preferably, it is 10 or less. If it is such a range, the adhesive layer with low affinity with a sealing material can be formed. The hydroxyl value of the said tackifying resin becomes like this. Preferably it is 60 or less, More preferably, it is 40 or less, More preferably, it is 20 or less. If it is such a range, the adhesive layer with low affinity with a sealing material can be formed.

(Rubber-based adhesive)

As the rubber-based pressure-sensitive adhesive, any appropriate pressure-sensitive adhesive may be used as long as the effect of the present invention is obtained. As the rubber-based pressure-sensitive adhesive, for example, natural rubber; Polyisoprene rubber, butadiene rubber, styrene-butadiene (SB) rubber, styrene-isoprene (SI) rubber, styrene-isoprene-styrene block copolymer (SIS) rubber, styrene-butadiene-styrene block copolymer (SBS) rubber, styrene ·Ethylene·butylene·styrene block copolymer (SEBS) rubber, styrene·ethylene·propylene·styrene block copolymer (SEPS) rubber, styrene·ethylene·propylene block copolymer (SEP) rubber, recycled rubber, butyl rubber, poly synthetic rubbers such as isobutylene rubber or modified products thereof; A rubber-based pressure-sensitive adhesive containing such as a base polymer is preferably used. This base polymer (rubber) has a low sp value, and when the said base polymer is used, the adhesive layer with low affinity with a sealing material can be formed.

As the base polymer constituting the rubber-based pressure-sensitive adhesive, polyisobutylene rubber, polyisoprene rubber or butyl rubber is particularly preferably used. When this rubber is used, it is possible to form an adhesive layer excellent in semiconductor chip retention at room temperature and excellent in releasability. Moreover, an adhesive layer with low affinity with a sealing material can be formed.

As the base polymer constituting the rubber-based adhesive, styrene/ethylene/propylene block copolymer (SEP) rubber, styrene/ethylene/butylene/styrene block copolymer (SEBS) rubber, and styrene/isoprene/styrene block copolymer (SIS) Rubber, styrene-butadiene-styrene block copolymer (SBS) rubber, and propylene rubber can also be preferably used. When this rubber is used, it is possible to form a pressure-sensitive adhesive layer capable of exhibiting high adhesiveness even in a high-temperature environment (eg, in a high-temperature environment in processing during semiconductor chip sealing). In the base polymer (rubber) having structural units derived from styrene, the content of the structural units derived from styrene is preferably 15% by weight or more with respect to all the structural units in the base polymer.

The rubber-based pressure-sensitive adhesive may include any appropriate additives, if necessary. Examples of the additive include a crosslinking agent, a vulcanizing agent, a tackifier, a plasticizer, a pigment, a dye, a filler, an anti-aging agent, a conductive material, an antistatic agent, an ultraviolet absorber, a light stabilizer, a peeling modifier, a softener, a surfactant, a flame retardant, an oxidation agent inhibitors; and the like.

As said tackifier contained in the said rubber-type adhesive, arbitrary appropriate tackifiers are used. As a tackifier, tackifying resin is used, for example. As a specific example of the said tackifying resin, rosin type tackifying resin, rosin derivative resin, petroleum type resin, terpene type resin, ketone type resin, etc. are mentioned. To [ the addition amount of the said tackifier / 100 weight part of base polymers ], Preferably they are 5 weight part - 100 weight part, More preferably, they are 10 weight part - 50 weight part.

As rosin-type resin contained in the said rubber-type adhesive, gum rosin, wood rosin, tall rosin, etc. are mentioned, for example. As the rosin-based resin, a stabilized rosin obtained by disproportionation or hydrogenation treatment of any appropriate rosin may be used. Further, as the rosin-based resin, a polymerized rosin which is a multimer (typically a dimer) of any suitable rosin, or a modified rosin obtained by modifying any suitable rosin (eg, modification with an unsaturated acid) may be used. .

Examples of the rosin derivative resin contained in the rubber pressure-sensitive adhesive include an esterified product of the rosin-based resin, a phenol-modified product of a rosin-based resin, and an esterified product of a phenol-modified rosin-based resin.

As petroleum resin contained in the said rubber-type adhesive, an aliphatic petroleum resin, an aromatic petroleum resin, a copolymerization type petroleum resin, an alicyclic type petroleum resin, these hydrides, etc. are mentioned, for example.

Examples of the terpene-based resin contained in the rubber-based pressure-sensitive adhesive include α-pinene resin, β-pinene resin, aromatic modified terpene-based resin, and terpene phenol-based resin.

Examples of the ketone-based resin contained in the rubber-based pressure-sensitive adhesive include ketone-based resins obtained by condensing ketones (eg, aliphatic ketones, alicyclic ketones) and formaldehyde.

As a crosslinking agent contained in the said rubber-type adhesive, an isocyanate type crosslinking agent etc. are mentioned, for example. Examples of the vulcanizing agent contained in the rubber pressure-sensitive adhesive include a thiuram-based vulcanizing agent, a quinoid-based vulcanizing agent, and a quinonedioxime-based vulcanizing agent. When the rubber-based pressure-sensitive adhesive contains a crosslinking agent and/or a vulcanizing agent, it is possible to form a pressure-sensitive adhesive layer having high cohesiveness and difficult to remain in the adhesive. The total content of the crosslinking agent and the vulcanizing agent is typically 0.1 to 20 parts by weight, more preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the base polymer.

In one embodiment, the rubber adhesive (Rub1) containing the said base polymer (rubber), a hydroxyl-containing polyolefin, and the crosslinking agent a which can react with the hydroxyl group of the said hydroxyl-group polyolefin is used. In this rubber-based adhesive, although the base polymer is not directly crosslinked, entanglement between the base polymer and the crosslinked hydroxyl group-containing polyolefin occurs, so-called pseudo crosslinking. As a result, a pressure-sensitive adhesive layer having high cohesiveness and difficult to remain in the pressure-sensitive adhesive can be formed. As the base polymer (rubber) used in this embodiment, the synthetic rubber is preferably used. In addition, as a crosslinking agent used for this embodiment, an isocyanate type crosslinking agent is used preferably.

The blending amount of the hydroxyl group-containing polyolefin is preferably 0.5 parts by weight or more, and more preferably 1.0 parts by weight or more, based on 100 parts by weight in total of the base polymer (rubber), the hydroxyl group-containing polyolefin, and the crosslinking agent a. If it is such a range, an adhesive layer with high cohesiveness can be formed. Moreover, when an adhesive sheet is provided with a base material layer, the adhesiveness ( anchoring force) of a base material layer and an adhesive layer can be improved. That is, if the compounding quantity of the said hydroxyl-containing polyolefin is the said range, an adhesive sheet with little adhesive residue can be obtained.

The blending amount of the crosslinking agent a is preferably 0.5 parts by weight or more, and more preferably 1.0 parts by weight or more, based on 100 parts by weight in total of the base polymer (rubber), the hydroxyl group-containing polyolefin, and the crosslinking agent a. If it is such a range, an adhesive layer with high cohesiveness can be formed. Moreover, when an adhesive sheet is provided with a base material layer, the adhesiveness ( anchoring force) of a base material layer and an adhesive layer can be improved. That is, if the compounding quantity of the said crosslinking agent a is the said range, the adhesive sheet with little adhesive residue can be obtained.

As the hydroxyl group-containing polyolefin, a resin excellent in compatibility with the synthetic rubber is preferably used. Examples of the hydroxyl group-containing polyolefin include polyethylene polyol, polypropylene polyol, polybutadiene polyol, hydrogenated polybutadiene polyol, polyisoprene polyol, and hydrogenated polyisoprene polyol. Among them, hydrogenated polyisoprene polyol, polyisoprene polyol, and polybutadiene polyol are preferable from the viewpoint of compatibility with the synthetic rubber.

The number average molecular weight (Mn) of the hydroxyl group-containing polyolefin is preferably 500 to 500,000, more preferably 1,000 to 200,000, and still more preferably 1,200 to 150,000. A number average molecular weight can be measured based on ASTMD2503.

The hydroxyl value (mgKOH/g) of the said hydroxyl-containing polyolefin becomes like this. Preferably it is 5-95, More preferably, it is 10-80. A hydroxyl value can be measured based on JISK1557:1970.

(Silicone-based adhesive)

As the silicone-based pressure-sensitive adhesive, any appropriate pressure-sensitive adhesive may be used as long as the effect of the present invention is obtained. As the silicone pressure sensitive adhesive, for example, a silicone pressure sensitive adhesive containing a silicone rubber or silicone resin containing organopolysiloxane as a base polymer is preferably used. As the base polymer constituting the silicone pressure-sensitive adhesive, a base polymer obtained by crosslinking the silicone rubber or silicone resin may be used. In addition, in this specification, "silicone rubber" means a polymer (for example, viscosity 1000 Pa·s) in which diorganosiloxane (D unit) as a main component is connected in a straight chain, and "silicone resin" is a main component refers to a polymer composed of triorganosilhemioxane (M unit) and silicate (Q unit) as a ).

As said silicone rubber, the organopolysiloxane etc. which contain dimethylsiloxane as a structural unit are mentioned, for example. A functional group (for example, a vinyl group) may be introduce|transduced into organopolysiloxane as needed. The weight average molecular weight of organopolysiloxane becomes like this. Preferably it is 100,000-1,000,000, More preferably, it is 150,000-500,000. A weight average molecular weight can be measured by GPC (solvent: THF).

As the silicone resin, for example, the R ₃ SiO _1/2 structural units, SiO ₂ structural units, RSiO _3/2 units, and R ₂ at least one configuration organopolysiloxane comprising units of the type of compound selected from SiO structural units (R is a monovalent hydrocarbon group or a hydroxyl group).

The silicone rubber and silicone resin may be used in combination. The weight ratio of the silicone rubber and the silicone resin in the silicone adhesive (rubber:resin) is preferably 100:0 to 100:220, more preferably 100:0 to 100:180, and still more preferably 100:10 to It is 100:100. The silicone rubber and the silicone resin may be contained in the silicone pressure-sensitive adhesive as a simple mixture, or may be contained in the silicone pressure-sensitive adhesive in a partially condensed form of the silicone rubber and the silicone resin. A rubber:resin ratio can also be calculated|required from the ratio of the Q unit (resin) and D unit (rubber) obtained by measuring the composition of a silicone adhesive ^{by 29 Si-NMR.}

The silicone-based pressure-sensitive adhesive may include any appropriate additives, if necessary. Examples of the additive include a crosslinking agent, a vulcanizing agent, a tackifier, a plasticizer, a pigment, a dye, a filler, an anti-aging agent, a conductive material, an antistatic agent, an ultraviolet absorber, a light stabilizer, a peeling modifier, a softener, a surfactant, a flame retardant, an oxidation agent inhibitors; and the like.

Preferably, the silicone pressure-sensitive adhesive includes a crosslinking agent. As said crosslinking agent, a siloxane type crosslinking agent, a peroxide type crosslinking agent, etc. are mentioned, for example. As the peroxide-based crosslinking agent, any suitable crosslinking agent may be used. Examples of the peroxide-based crosslinking agent include benzoyl peroxide, t-butylperoxybenzoate, dicumyl peroxide, and the like. As a siloxane type crosslinking agent, polyorganohydrogensiloxane etc. are mentioned, for example. The polyorganohydrogensiloxane preferably has two or more hydrogen atoms bonded to silicon atoms. In addition, the polyorganohydrogensiloxane preferably has an alkyl group, a phenyl group, and a halogenated alkyl group as a functional group bonded to a silicon atom.

(Active energy ray-curable adhesive)

As said adhesive, you may use the active energy ray hardening-type adhesive which can be hardened (high elastic modulus) by irradiation of an active energy ray. When an active energy ray-curable pressure-sensitive adhesive is used, a pressure-sensitive adhesive sheet capable of reducing adhesive strength by irradiating active energy ray in a scene requiring peeling can be obtained. have. Examples of active energy rays include gamma rays, ultraviolet rays, visible rays, infrared rays (hot rays), radio waves, alpha rays, beta rays, electron rays, plasmas, ionizing rays, and particle rays. In addition, in this specification, simply in the case of "adhesive layer", it means the adhesive layer before an adhesive is hardened and adhesive force falls.

As a resin material constituting the active energy ray-curable pressure-sensitive adhesive, for example, an ultraviolet curing system (Kiyomi Kato, published by the Comprehensive Technology Center, (1989)), a photocuring technology (Technical Information Association edition (2000)), Japanese Patent The resin material described in Unexamined-Japanese-Patent No. 2003-292916, patent 4151850, etc. is mentioned. More specifically, the resin material (R1) containing the polymer used as a base material, and an active energy ray-reactive compound (monomer or an oligomer), the resin material (R2) containing an active energy ray-reactive polymer, etc. are mentioned.

Examples of the polymer used as the parent material include natural rubber, polyisobutylene rubber, styrene-butadiene rubber, styrene-isoprene-styrene block copolymer rubber, regenerated rubber, butyl rubber, polyisobutylene rubber, and nitrile rubber (NBR). ) rubber-based polymers such as; silicone-based polymers; An acrylic polymer etc. are mentioned. You may use this polymer individually or in combination of 2 or more types. As the polymer serving as the base material, the polymers exemplified as the base polymer of the acrylic pressure-sensitive adhesive, rubber-based pressure-sensitive adhesive or silicone pressure-sensitive adhesive are preferably used from the viewpoint of affinity with the sealing material.

Examples of the active energy ray-reactive compound include a photoreactive monomer or oligomer having a functional group having a carbon-carbon multiple bond, such as an acryloyl group, a methacryloyl group, a vinyl group, an allyl group, and an acetylene group. . Specific examples of the photoreactive monomer or oligomer include trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acryl Rate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylic (meth)acryloyl group containing compounds, such as a rate and polyethyleneglycol di(meth)acrylate; 2 to pentamers of this (meth)acryloyl group-containing compound; and the like.

Further, examples of the active energy ray-reactive compound include monomers such as epoxidized butadiene, glycidyl methacrylate, acrylamide, and vinylsiloxane; Or you may use the oligomer comprised from the said monomer. Resin material (R1) containing these compounds can be hardened|cured by high energy rays, such as an ultraviolet-ray and an electron beam.

Moreover, as said active energy ray-reactive compound, you may use the mixture of organic salts, such as an onium salt, and the compound which has a some heterocyclic ring in a molecule|numerator. In the mixture, an organic salt is cleaved by irradiation of active energy rays (eg, ultraviolet rays, electron beams) to generate ions, which become an initiating species and cause a heterocyclic ring-opening reaction to form a three-dimensional network structure. . As said organic salt, an iodonium salt, a phosphonium salt, an antimonium salt, a sulfonium salt, a borate salt etc. are mentioned, for example. Examples of the heterocycle in the compound having a plurality of heterocycles in the molecule include oxirane, oxetane, oxolane, thiirane, and aziridine.

In the resin material (R1) containing the polymer serving as the base material and the active energy ray-reactive compound, the content of the active energy ray-reactive compound is preferably 0.1 parts by weight to 500 parts by weight with respect to 100 parts by weight of the polymer serving as the base material. It is a weight part, More preferably, it is 1 weight part - 300 weight part, More preferably, it is 10 weight part - 200 weight part. If it is such a range, the adhesive layer with low affinity with a sealing material can be formed.

The resin material (R1) containing the polymer serving as the base material and the active energy ray-reactive compound may contain any appropriate additives as necessary. As an additive, an active energy ray polymerization initiator, an active energy ray polymerization accelerator, a crosslinking agent, a plasticizer, a vulcanizing agent, etc. are mentioned, for example. As the active energy ray polymerization initiator, any appropriate initiator can be used depending on the kind of active energy ray to be used. An active energy ray polymerization initiator may be used individually or in combination of 2 or more types. In the resin material (R1) containing the polymer serving as the base material and the active energy ray-reactive compound, the content ratio of the active energy ray polymerization initiator is preferably 0.1 parts by weight to 10 parts by weight with respect to 100 parts by weight of the polymer serving as the base material. parts, and more preferably 1 part by weight to 5 parts by weight.

As said active energy ray-reactive polymer, the polymer which has functional groups which have carbon-carbon multiple bonds, such as an acryloyl group, a methacryloyl group, a vinyl group, an allyl group, and an acetylene group, is mentioned, for example. As a specific example of the polymer which has an active-energy-ray-reactive functional group, the polymer etc. comprised from polyfunctional (meth)acrylate are mentioned. The polymer composed of the polyfunctional (meth)acrylate preferably has an alkyl ester having 4 or more carbon atoms, more preferably an alkyl ester having 6 or more carbon atoms, and still more preferably an alkyl ester having 8 or more carbon atoms. It is particularly preferable to have an alkyl ester having 8 to 20 carbon atoms, and most preferably to have an alkyl ester having 8 to 18 carbon atoms. When a polymer having a long side chain is used, a pressure-sensitive adhesive layer having low affinity with the sealing material can be formed. The said polymer WHEREIN: The content rate of the structural unit which has a C4 or more alkylester as a side chain becomes like this with respect to all the structural units which comprise the said polymer, Preferably it is 30 weight% or more, More preferably, it is 50 weight% or more. and more preferably 70% by weight to 100% by weight, and particularly preferably 80% by weight to 100% by weight. If it is such a range, the adhesive layer with low affinity with a sealing material can be formed.

The resin material (R2) containing the active energy ray-reactive polymer may further contain the active energy ray-reactive compound (monomer or oligomer). In addition, the resin material (R2) containing the said active energy ray-reactive polymer may contain arbitrary appropriate additives as needed. The specific example of an additive is the same as the additive which can be contained in the resin material (R1) containing the polymer used as a base material, and an active energy ray-reactive compound. In the resin material (R2) containing the active energy ray-reactive polymer, the content of the active energy ray polymerization initiator is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the active energy ray-reactive polymer, more Preferably, it is 1 part by weight to 5 parts by weight.

<Thermal expansible microspheres>

In one embodiment, the said adhesive layer further contains thermally expansible microsphere. When the adhesive sheet provided with the adhesive layer containing thermally expansible microspheres is heated, the said thermally expansible microsphere expands or foams, and unevenness|corrugation generate|occur|produces on an adhesive surface, As a result, adhesive force falls or lose|disappears. Such an adhesive sheet can be peeled easily by heating.

Any suitable thermally expansible microsphere can be used as said thermally expansible microsphere, as long as it is a microsphere which can expand or foam by heating. As said thermally expansible microsphere, the microsphere which encapsulates the substance which expands easily by heating in the outer skin which has elasticity, for example can be used. These thermally expansible microspheres can be manufactured by arbitrary suitable methods, for example, a core-servation method, an interfacial polymerization method, etc.

Examples of the substance that expands easily by heating include propane, propylene, butene, normal butane, isobutane, isopentane, neopentane, normal pentane, normal hexane, isohexane, heptane, octane, petroleum ether, methane halogen low-boiling-point liquids such as cargo and tetraalkylsilane; azodicarbonamide gasified by thermal decomposition; and the like.

Examples of the material constituting the outer shell include nitrile monomers such as acrylonitrile, methacrylonitrile, α-chloracrylonitrile, α-ethoxyacrylonitrile, and fumaronitrile; carboxylic acid monomers such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, and citraconic acid; vinylidene chloride; vinyl acetate; Methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, isobornyl (meth) acrylate, cyclo (meth)acrylic acid esters, such as hexyl (meth)acrylate, benzyl (meth)acrylate, and (beta)-carboxyethyl acrylate; styrene monomers such as styrene, α-methylstyrene and chlorostyrene; amide monomers such as acrylamide, substituted acrylamide, methacrylamide, and substituted methacrylamide; and polymers composed of A homopolymer may be sufficient as the polymer comprised from this monomer, and a copolymer may be sufficient as it. Examples of the copolymer include vinylidene chloride-methyl methacrylate-acrylonitrile copolymer, methyl methacrylate-acrylonitrile-methacrylonitrile copolymer, methyl methacrylate-acrylonitrile copolymer, An acrylonitrile-methacrylonitrile-itaconic acid copolymer etc. are mentioned.

As said thermally expansible microsphere, you may use an inorganic type foaming agent or an organic type foaming agent. Examples of the inorganic foaming agent include ammonium carbonate, ammonium hydrogen carbonate, sodium hydrogen carbonate, ammonium nitrite, sodium boron hydroxide, and various azides. Examples of the organic foaming agent include salt fluorinated alkane compounds such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; Hydrazine compounds such as paratoluenesulfonylhydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis(benzenesulfonylhydrazide), and allylbis(sulfonylhydrazide) ; semicarbazide compounds such as p-toluylenesulfonyl semicarbazide and 4,4'-oxybis(benzenesulfonyl semicarbazide); triazole-based compounds such as 5-morpholyl-1,2,3,4-thiatriazole; N,N'-dinitrosopentamethylenetetramine, N,N'-dimethyl-N,N'-dinitrosoterephthalamide; N-nitroso compounds, such as these, etc. are mentioned.

A commercial item may be used for the said thermally expansible microsphere. Specific examples of commercially available thermally expansible microspheres include "Matsumoto Microspare" manufactured by Matsumoto Yushi Seyaku Co., Ltd. (grades: F-30, F-30D, F-36D, F-36LV, F-50, F-50D, F-65, F-65D, FN-100SS, FN-100SSD, FN-180SS, FN-180SSD, F-190D, F-260D, F-2800D), Nippon Pyrite's brand name "Expansle" (grade: 053-40, 031-40, 920-40, 909-80, 930-120), “Dieform” manufactured by Kureha Chemical High School (Grades: H750, H850, H1100, S2320D, S2640D, M330, M430, M520) , Sekisui Chemical Co., Ltd. "Advancell" (grade: EML101, EMH204, EHM301, EHM302, EHM303, EM304, EHM401, EM403, EM501) etc. are mentioned.

The particle diameter of the thermally expansible microspheres before heating is preferably 0.5 µm to 80 µm, more preferably 5 µm to 45 µm, still more preferably 10 µm to 20 µm, particularly preferably 10 µm to 15 μm. Therefore, when the particle size before heating of the said thermally expansible microsphere speaks as an average particle diameter, Preferably it is 6 micrometers - 45 micrometers, More preferably, it is 15 micrometers - 35 micrometers. The said particle diameter and an average particle diameter are values calculated|required by the particle size distribution measuring method in a laser scattering method.

The thermally expansible microsphere preferably has a suitable strength not to be ruptured until the volume expansion rate is preferably 5 times or more, more preferably 7 times or more, still more preferably 10 times or more. When using such thermally expansible microspheres, adhesive force can be efficiently reduced by heat processing.

The content rate of the thermally expansible microsphere in the said adhesive layer can be set suitably according to the fall property of desired adhesive force, etc. The content of the thermally expansible microspheres is, for example, 1 part by weight to 150 parts by weight, preferably 10 parts by weight to 130 parts by weight, and more preferably 25 parts by weight with respect to 100 parts by weight of the base polymer forming the pressure-sensitive adhesive layer. parts by weight to 100 parts by weight.

When the pressure-sensitive adhesive layer contains thermally expansible microspheres, the arithmetic surface roughness Ra of the pressure-sensitive adhesive layer before thermally expansible microspheres is expanded (that is, before heating) is preferably 500 nm or less, more preferably 400 It is nm or less, More preferably, it is 300 nm or less. If it is such a range, the adhesive sheet excellent in the adhesiveness with respect to a to-be-adhered body can be obtained. The pressure-sensitive adhesive layer having such excellent surface smoothness can be obtained, for example, by making the thickness of the pressure-sensitive adhesive layer within the above range, or by applying and transferring the pressure-sensitive adhesive layer to a separator when a separate pressure-sensitive adhesive layer is provided. Moreover, as demonstrated in said A section, when the adhesive sheet of this invention is further equipped with another adhesive layer, the said other adhesive layer may contain thermally expansible microsphere. Also when another adhesive layer contains thermally expansible microsphere, it is preferable that arithmetic surface roughness Ra of the said adhesive layer is the said range.

When the pressure-sensitive adhesive layer contains thermally expansible microspheres, the pressure-sensitive adhesive layer has a dynamic storage elastic modulus at 80°C of 5 kPa to 1 MPa (more preferably 10 kPa to 0.8 MPa) as a base polymer in the range It is preferable to include an adhesive to be constituted. If it is such an adhesive layer, it can have moderate adhesiveness before a heating, and can form the adhesive sheet which adhesive force falls easily by heating. In addition, the dynamic storage elastic modulus can be measured using the dynamic viscoelasticity measuring apparatus (For example, the brand name "ARES" manufactured by Rheometrics Corporation), under measurement conditions of a frequency of 1 Hz and a temperature increase rate of 10 degrees C/min.

C. base layer

In one embodiment, the adhesive sheet of this invention is equipped with an adhesive layer and a base material layer. 2A is a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention. The pressure-sensitive adhesive sheet 100 includes a pressure-sensitive adhesive layer 10 and a base material layer 30 disposed on one side of the pressure-sensitive adhesive layer 10 . 2B is a schematic cross-sectional view of an adhesive sheet according to another embodiment of the present invention. The pressure-sensitive adhesive sheet 200 includes a pressure-sensitive adhesive layer 10 and a substrate layer 30 , and the pressure-sensitive adhesive layer 10 is disposed on both sides of the substrate layer 30 . An adhesive layer of the same structure may be sufficient as the adhesive layer with two layers, respectively, and the adhesive layer of a different structure may be sufficient as it. Moreover, the structure provided with the said adhesive layer on one side of a base material layer and equipped with another adhesive layer on the other side may be sufficient.

When the adhesive sheet of this invention is equipped with a base material layer, the anchoring force of the said base material layer and an adhesive layer becomes like this. Preferably it is 6.0 N/19 mm or more, More preferably, it is 15 N/19 mm or more.

The anchoring force can be measured as follows. The anchoring force is (i) the entire surface of the adhesive sheet having a width of 20 mm and a length of 150 mm on the opposite side to the pressure-sensitive adhesive layer (eg, the outer surface of the substrate layer in the case of an adhesive sheet having a substrate layer/adhesive layer configuration) A SUS plate is adhered to the surface via a predetermined double-sided tape, and (ii) an adhesive evaluation sheet containing a polyester resin having a size of 19 mm in width x 150 mm in length on the outer surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet. (A sheet having peel-off adhesive force of 10N/20mm to 20N/20mm with respect to polyethylene terephthalate, for example, Nitto Denko Co., Ltd. trade name "No.315 tape") is attached to prepare a sample for evaluation, , (iii) It is obtained by measuring the peeling force between the base material layer of an adhesive sheet, and an adhesive layer by a tensile test. In addition, said (i)-(iii) is performed under the environmental temperature of 23 degreeC. The conditions of the tensile test at the time of measuring the peel force are a peeling rate of 50 mm/min, and a peeling angle of 180 degrees.

As mentioned above, the adhesive sheet with high anchoring force of a base material layer and an adhesive layer is an adhesive sheet which an adhesive does not easily remain in nature, and if it is such an adhesive sheet, the effect of this invention becomes remarkable. When evaluated by the said method, it is more preferable that peeling does not generate|occur|produce at the interface of a base material layer and an adhesive layer, for example, it is more preferable that it is an adhesive sheet peeled between a SUS board and a base material layer. An adhesive sheet with high anchoring force can be obtained by using the said rubber adhesive (Rub1) as an adhesive, adding an isocyanate type crosslinking agent in an adhesive, etc., for example.

As said base material layer, a resin sheet, a nonwoven fabric, paper, metal foil, a woven fabric, a rubber sheet, foam seat|seet, this laminated body (particularly, the laminated body containing a resin sheet) etc. are mentioned, for example. Examples of the resin constituting the resin sheet include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyethylene (PE), polypropylene (PP), and ethylene-propylene copolymer. , ethylene-vinyl acetate copolymer (EVA), polyamide (nylon), wholly aromatic polyamide (aramid), polyimide (PI), polyvinyl chloride (PVC), polyphenylene sulfide (PPS), fluororesin, poly Ether ether ketone (PEEK) etc. are mentioned. Examples of the nonwoven fabric include nonwoven fabrics made of natural fibers having heat resistance, such as nonwoven fabrics made of manila hemp; Synthetic resin nonwoven fabrics, such as a polypropylene resin nonwoven fabric, a polyethylene resin nonwoven fabric, and an ester type resin nonwoven fabric, etc. are mentioned. As metal foil, copper foil, stainless foil, aluminum foil, etc. are mentioned. As paper, Japanese paper, kraft paper, etc. are mentioned.

The thickness of the base layer may be set to any suitable thickness according to desired strength or flexibility, and purpose of use. The thickness of the base layer is preferably 1000 μm or less, more preferably 1 μm to 1000 μm, still more preferably 1 μm to 500 μm, particularly preferably 3 μm to 300 μm, most preferably is 5 μm to 250 μm.

The said base material layer may be surface-treated. Examples of the surface treatment include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high-pressure electric shock exposure, ionizing radiation treatment, and coating treatment with a primer.

As said organic coating material, the material described in plastic hard-coating material II (CMC publication, (2004)) is mentioned, for example. Preferably, a urethane-based polymer, more preferably polyacrylic urethane, polyester urethane, or a precursor thereof is used. This is because coating and application to the base material is simple, and industrially, a wide variety of things can be selected and can be obtained inexpensively. The urethane-based polymer is, for example, a polymer comprising a reaction mixture of an isocyanato monomer and an alcoholic hydroxyl group-containing monomer (for example, a hydroxyl group-containing acrylic compound or a hydroxyl group-containing ester compound). The organic coating material may contain a chain extender such as polyamine, an anti-aging agent, an oxidation stabilizer, and the like as optional additives. Although the thickness of an organic coating layer is not specifically limited, For example, 0.1 micrometer - about 10 micrometers are suitable, 0.1 micrometer - about 5 micrometers are preferable, and 0.5 micrometer - about 5 micrometers are more preferable.

D. elastic layer

The pressure-sensitive adhesive sheet of the present invention may further include an elastic layer. 3 is a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention. The adhesive sheet 300 further includes an elastic layer 40 . The elastic layer 40 may be preferably disposed when the pressure-sensitive adhesive layer 10 includes the thermally expansible microspheres. In addition, when the adhesive sheet 300 is equipped with the base material layer 30, the elastic layer 40 may be arrange|positioned between the adhesive layer 10 and the base material layer 30 like the example shown in figure, and a base material You may provide on the opposite side to the adhesive layer of a layer. Two or more elastic layers 40 may be provided. In addition, in FIG. 3, it has one layer of the elastic layer 40, and the example in which the said elastic layer 40 is arrange|positioned between the adhesive layer 10 and the base material layer 30 is shown. By providing the elastic layer 40, the followability to the adherend is improved. Moreover, when the adhesive sheet provided with the elastic layer 40 is heated at the time of peeling, the deformation|transformation (expansion) of the surface direction of an adhesive layer is restrained, and the deformation|transformation in the thickness direction takes priority. As a result, peelability improves.

The elastic layer includes a base polymer, and as the base polymer, the polymer exemplified as the base polymer constituting the pressure-sensitive adhesive layer may be used. Moreover, the said elastic layer may contain natural rubber, synthetic rubber, synthetic resin, etc. Examples of the synthetic rubber and synthetic resin include nitrile, diene, and acrylic synthetic rubbers; Thermoplastic elastomers, such as a polyolefin type and polyester type; ethylene-vinyl acetate copolymer; Polyurethane; polybutadiene; Soft polyvinyl chloride etc. are mentioned. The base polymer constituting the elastic layer may be the same as or different from the base polymer constituting the pressure-sensitive adhesive layer. The elastic layer may be a foamed film formed of the base polymer. The said foamed film can be obtained by arbitrary appropriate methods. Further, the elastic layer and the pressure-sensitive adhesive layer can be distinguished by the difference in the base polymer and/or the presence or absence of thermally expansible microspheres (the elastic layer does not contain thermally expansible microspheres).

The elastic layer may contain any suitable additives, if necessary. As said additive, a crosslinking agent, a vulcanizing agent, a tackifier, a plasticizer, a softening agent, a filler, an anti-aging agent, etc. are mentioned, for example. When a hard resin such as polyvinyl chloride is used as the base polymer, it is preferable to use a plasticizer and/or a softening agent together to form an elastic layer having desired elasticity.

The thickness of the elastic layer is preferably 3 µm to 200 µm, and more preferably 5 µm to 100 µm. If it is within such a range, the said function of an elastic layer can fully be exhibited.

The elastic modulus of elasticity at 25°C of the elastic layer is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, still more preferably 0.1 MPa to 10 MPa. If it is within such a range, the said function of an elastic layer can fully be exhibited.

E. separator

The adhesive sheet of this invention can be further equipped with a separator as needed. At least one surface of the separator is a peeling surface, and may be installed to protect the pressure-sensitive adhesive layer. The separator may be made of any suitable material.

F. Manufacturing method of adhesive sheet

The adhesive sheet of this invention can be manufactured by arbitrary appropriate methods. The pressure-sensitive adhesive sheet of the present invention is, for example, a method of coating a composition containing an pressure-sensitive adhesive directly on a base layer (in the case of obtaining a pressure-sensitive adhesive sheet containing no base layer, any suitable substrate), or any suitable substrate The method of transferring the coating layer formed by coating the composition containing an adhesive on it to a base material layer, etc. are mentioned. The composition comprising the pressure-sensitive adhesive may include any suitable solvent.

In the case of forming the pressure-sensitive adhesive layer including the thermally expansible microspheres, a composition including the thermally expansible microspheres, the pressure-sensitive adhesive, and any suitable solvent may be applied to the base layer to form the pressure-sensitive adhesive layer. Alternatively, the heat-expandable microspheres may be sprinkled on the pressure-sensitive adhesive coating layer, then the heat-expandable microspheres may be embedded in the pressure-sensitive adhesive using a laminator or the like to form a pressure-sensitive adhesive layer containing the heat-expandable microspheres.

When the pressure-sensitive adhesive layer has the elastic layer, the elastic layer can be formed by, for example, coating the composition for forming the elastic layer on the base layer or the pressure-sensitive adhesive layer.

Any suitable coating method may be employed as the method for applying the pressure-sensitive adhesive and each composition. For example, after application|coating, it can dry and form each layer. As a coating method, the coating method using a multi-coater, a die-coater, a gravure coater, an applicator etc. is mentioned, for example. As a drying method, natural drying, heat drying, etc. are mentioned, for example. The heating temperature in the case of heating and drying may be set to any suitable temperature according to the characteristics of the material to be dried.

[Example]

Hereinafter, the present invention will be specifically described by way of Examples, but the present invention is not limited by these Examples. The evaluation method in an Example is as follows. In addition, in the Example, unless otherwise indicated, "part" and "%" are based on weight.

(1) contact angle

The pressure-sensitive adhesive sheet was placed on a slide glass with the pressure-sensitive adhesive layer facing up, and the contact angle of the pressure-sensitive adhesive layer surface with respect to 4-tert-butylphenyl glycidyl ether was measured.

2 µl of 4-tert-butylphenyl glycidyl ether was dripped at the pressure-sensitive adhesive layer surface, and the contact angle after 5 seconds was measured (N=5). The measurement of the contact angle was performed in the atmosphere of 23 degreeC and 50%RH using the contact angle meter (Kyohwa Co., Ltd. make, brand name "CX-A type").

(2) sp value

The sp value of the polymer in the pressure-sensitive adhesive layer after forming the pressure-sensitive adhesive sheet is determined by the method of Fedors (Hideki Yamamoto, "Sp Value Basics, Application and Calculation Method", published by Joho Kiko Co., Ltd., April 3, 2006 , pages 66 to 67). Specifically, the sp value is the evaporation energy Δe (cal) of each atom or group of atoms forming the polymer at 25°C, and the molar volume ΔV (cm 3 ) of each atom or group of atoms forming the polymer at 25°C. ), it was calculated by the following formula.

Sp value = (ΣΔe/ΣΔV) ^1/2

In addition, when the polymer is a copolymer, the SP value is calculated by calculating the SP value of each homopolymer of each structural unit constituting the copolymer, and multiplying each of these SP values by the mole fraction of each structural unit. It is calculated by summing

In the above case, in the analysis method of each structural unit (composition analysis of polymer), only the pressure-sensitive adhesive layer is appropriately collected from the pressure-sensitive adhesive sheet, and immersed in an organic solvent such as dimethylformamide (DMF), acetone, methanol, or tetrahydrofuran (THF). The solvent-soluble part obtained by doing this is collect|recovered, and it can obtain|require from the analytical method of a gel filtration permeation chromatography (GPC), nuclear magnetic resonance spectroscopy (NMR), infrared spectroscopy (IR), and mass spectrometry.

(3) Adhesion

On the entire surface of the side opposite to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet (width 20 mm x length 140 mm), a double-sided adhesive tape (manufactured by Nitto Denko Corporation, trade name “No. was used for bonding.

Then, on the entire surface of the pressure-sensitive adhesive layer, a polyethylene terephthalate film (manufactured by Toray Corporation, trade name "Lumirer S-10", thickness: 25 µm, width: 30 mm) was adhered (temperature: 23°C, humidity: 65) %, 2 kg roller 1 round trip).

The sample for evaluation obtained as mentioned above was used for a tensile test. As a tensile testing machine, the brand name "Shimadzu Autograph AG-120kN" manufactured by Shimadzu Corporation was used. After setting the sample for evaluation in the tensile testing machine, and leaving it to stand for 30 minutes under the environmental temperature of 23 degreeC, the tensile test was started. The conditions of the tensile test were: peeling angle: 180°, peeling speed (tensile speed): 300 mm/min. The load at the time of peeling an adhesive sheet from the said PET film was measured, and the maximum load at that time was made into the adhesive force of the adhesive sheet.

(4) anchoring power

On the entire surface of the side opposite to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet (width 20 mm x length 140 mm), a double-sided adhesive tape (Nitto Denko Co., Ltd., trade name "No. 531") was interposed, and a SUS304 plate (width 40 mm) was interposed. × length 120 mm) was adhered using a 2 kg hand roller.

Then, a sheet for evaluation (Nitto Denko Co., Ltd., trade name "No. 315 Tape", width 19 mm x length 150 mm) was adhered (temperature: 23°C, humidity: 65%, 2 kg roller 1 reciprocation).

The sample for evaluation obtained as mentioned above was used for a tensile test. As a tensile testing machine, the brand name "Shimadzu Autograph AG-120kN" manufactured by Shimadzu Corporation was used. The conditions of the tensile test were: peeling angle: 180°, peeling speed (tensile speed): 50 mm/min. The said sheet for evaluation was hold|gripped and the load at the time of trying to peel an adhesive layer from the base material layer of an adhesive sheet was measured, and the maximum load at that time was made into anchoring force of a base material layer and an adhesive layer.

(5) tag value

On the entire surface of the side opposite to the pressure-sensitive adhesive layer of the adhesive sheet (width 20 mm x length 50 mm), a double-sided adhesive tape (Nitto Denko Co., Ltd., trade name "No. 531") was interposed, and slide glass (Matsunami Glass) was interposed. The industrial company make, 26 mm x 76 mm) was adhere|attached using the 2 kg hand roller.

The probe tag value of the outer surface of the adhesive layer in the sample for evaluation obtained as mentioned above was measured using the probe tag measuring machine (The RHESCA company make, brand name "TACKINESS Model TAC-II"). Measurement conditions were: Immersion speed: 30 mm/min, test speed: 30 mm/min, preload: 100 gf, press time: 1 second, probe area (Probe Area): 5 mmφ SUS.

(6) Holding capacity test

Under an environmental temperature of 23°C, the entire outer surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet (width 10 mm × length 150 mm) was applied to a bakelite plate (manufactured by Futamura Chemical Co., Ltd., trade name “Daikolite FL-102”, width 25 mm × It adhered to the central part of length 125 mm x thickness 2 mm using a 2 kg hand roller.

After aging the sample for evaluation obtained as described above by leaving it to stand for 30 minutes under an environmental temperature of 40°C, a tape creep tester (manufactured by Imada Seisakusho, model/model number "12-station weight type/041") A load of 1.96N was applied using a , and the state was maintained and left for 2 hours.

On the basis of the position before pressurization on the bakelite plate, the movement distance (shift) of the adhesive sheet by pressurization was measured. It shows that the holding force is so high that the said moving distance is short.

(7) surface roughness

Arithmetic surface roughness Ra of the surface of the adhesive layer of an adhesive sheet was measured according to JISB0601. An optical surface roughness meter (manufactured by Veeco Metrogy Group, trade name "Wyko NT9100") was used as the measuring instrument.

(8) Stand-off suppression effect

100 parts by weight of a naphthalene-type bifunctional epoxy resin (manufactured by DIC, trade name "HP4032D", epoxy equivalent: 144), 40 parts by weight of a phenoxy resin (manufactured by Mitsui Chemicals, trade name "EP4250"), and a phenol resin (Meiwa Chemicals) 129 parts by weight of spherical silica (manufactured by Admatex, brand name "SO-25R") and 1137 parts by weight of spherical silica (manufactured by Orient Chemical Co., Ltd., brand name "OIL BLACK BS") 14 parts by weight, 1 part by weight of a curing catalyst (manufactured by Shikoku Chemical Co., Ltd., trade name "2PHZ-PW"), and 30 parts by weight of methyl ethyl ketone were mixed to prepare a resin solution A (solid content concentration: 23.6% by weight).

On the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, a Si wafer (1 cm × 1 cm, thickness 500 µm) is placed, and the Si wafer is covered and sealed on the pressure-sensitive adhesive layer, and the resin solution A is applied (applying) Size: 3 cm x 3 cm), the resin solution was cured by heating at 170 DEG C for 10 minutes to form a structure composed of a Si wafer and a sealing resin on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet.

After cooling, the pressure-sensitive adhesive sheet was peeled from the structure. About the adhesive sheet after peeling, the difference of the adhesive layer thickness of the part which did not contact the Si wafer, and the adhesive layer thickness of the part which contacted the Si wafer was made into the stand-off amount.

(9) adhesive residue

In the same manner as in (8) above, a structure comprising a Si wafer and a sealing resin was formed on the pressure-sensitive adhesive sheet, and after cooling, the pressure-sensitive adhesive sheet was peeled from the structure. After peeling, the adhesive surface of the structure was observed under a microscope (manufactured by Keyence, trade name "VHX-100", magnification: 150 times), and the presence or absence of the adhesive layer component as it was attached to the structure was confirmed. In Table 1, the case where there were fewer than 5 deposits with a particle diameter of 100 micrometers (in the case of an amorphous shape, the longest side length of 100 micrometers) or more was made into (circle) and the case where 5 or more were made into x.

[Example 1]

100 parts by weight of an acrylic copolymer as a base polymer (a copolymer of 2ethylhexyl acrylate and hydroxyethyl acrylate, 2ethylhexyl acrylate structural unit: hydroxyethyl acrylate structural unit = 100:5 (weight ratio)), and an isocyanate type Mix 1.5 parts by weight of a crosslinking agent (manufactured by Nippon Polyurethane, trade name "Coronate L", 10 parts by weight of a terpene phenol-based tackifying resin (manufactured by Yasuhara Chemical Corporation, trade name "YS Polyster S145")) and 100 parts by weight of toluene, A composition for forming a pressure-sensitive adhesive layer was prepared.

The composition for forming the pressure-sensitive adhesive layer was coated on one side of a polytetrafluoroethylene film (manufactured by Toray Corporation, trade name “Lumiror S10”, thickness 38 μm) as a base layer, and formed into a base layer and an adhesive layer (thickness 10 μm). The adhesive sheet comprised was obtained.

[Example 2]

Acrylic copolymer as base polymer (copolymer of 2ethylhexyl acrylate and acrylic acid and trimethylolpropane acrylate, 2ethylhexyl acrylate structural unit: acrylic acid structural unit: trimethylolpropane acrylate structural unit = 100:3:0.03 (weight ratio) )) 100 parts by weight, 0.5 parts by weight of an epoxy-based crosslinking agent (manufactured by Mitsubishi Gas Chemical, trade name “Tetrad C”), and a terpene phenol-based tackifying resin (manufactured by Yasuhara Chemicals, trade name “YS Polyster S145”) 10 A composition for forming a pressure-sensitive adhesive layer was prepared by mixing parts by weight and 100 parts by weight of toluene.

The composition for forming the pressure-sensitive adhesive layer was coated on one side of a polytetrafluoroethylene film (manufactured by Toray Corporation, trade name “Lumiror S10”, thickness 38 μm) as a base layer, and formed into a base layer and an adhesive layer (thickness 10 μm). The adhesive sheet comprised was obtained.

[Example 3]

100 parts by weight of an addition reaction type silicone pressure-sensitive adhesive (manufactured by Toray Corporation, trade name "silicone rubber SD-4580L", silicone rubber: silicone resin = 60:40 (weight ratio)), and a platinum-based catalyst (manufactured by Toray Corporation, trade name "SRX-212") 0.5 parts by weight and 100 parts by weight of toluene were mixed to prepare a composition for forming a pressure-sensitive adhesive layer.

The composition for forming the pressure-sensitive adhesive layer is coated on one side of a polyimide film (manufactured by Toray DuPont, trade name “Kapton 200H”, thickness 50 μm) as a base layer, and an adhesive sheet composed of a base layer and an adhesive layer (10 μm) got

[Example 4]

100 parts by weight of a polyisobutylene rubber (manufactured by BASF Japan, trade name "Opanol B80"), 1.5 parts by weight of a hydroxyl group-containing polyolefin (manufactured by Idemitsu Kosan Corporation, trade name "Epol"), and an isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Kogyo Co., Ltd.) , trade name "Coronate L") 4 parts by weight and 200 parts by weight of toluene were mixed to prepare a composition for forming an adhesive layer.

The composition for forming the pressure-sensitive adhesive is coated on one side of a polytetrafluoroethylene film (manufactured by Toray Corporation, trade name “Lumiror S10”, thickness 38 μm) as a base layer, and is composed of a base layer and an adhesive layer (thickness 10 μm). A pressure-sensitive adhesive sheet was obtained.

[Example 5]

To the composition for forming the pressure-sensitive adhesive layer, 30 parts by weight of thermally expansible microspheres (manufactured by Matsumoto Yushi Seyaku Co., Ltd., trade name “Matsumoto Microspare F-50”) were further added, and the thickness of the pressure-sensitive adhesive layer was set to 40 µm. It carried out similarly to Example 1, and obtained the adhesive sheet.

[Example 6]

To the composition for forming the pressure-sensitive adhesive layer, 30 parts by weight of thermally expansible microspheres (manufactured by Matsumoto Yushi Seyaku Co., Ltd., trade name “Matsumoto Microspare F-50”) were further added, and the thickness of the pressure-sensitive adhesive layer was set to 40 µm. It carried out similarly to Example 2, and obtained the adhesive sheet.

[Example 7]

To the composition for forming the pressure-sensitive adhesive layer, 30 parts by weight of thermally expansible microspheres (manufactured by Matsumoto Yushi Seyaku Co., Ltd., trade name “Matsumoto Microspare F-50”) were further added, and the thickness of the pressure-sensitive adhesive layer was set to 40 µm. It carried out similarly to Example 3, and obtained the adhesive sheet.

[Example 8]

To the composition for forming the pressure-sensitive adhesive layer, 30 parts by weight of thermally expansible microspheres (manufactured by Matsumoto Yushi Seyaku Co., Ltd., trade name “Matsumoto Microspare F-50”) were further added, and the thickness of the pressure-sensitive adhesive layer was set to 40 µm. It carried out similarly to Example 4, and obtained the adhesive sheet.

[Example 9]

It carried out similarly to Example 1, and manufactured the composition for adhesive layer formation.

Acrylic copolymer (copolymer of ethyl acrylate, 2 ethylhexyl acrylate, and hydroxyethyl acrylate, ethyl acrylate structural unit: 2 ethylhexyl acrylate structural unit: hydroxyethyl acrylate structural unit: 70:30:5:6 ( Weight ratio)) 100 parts by weight), 2 parts by weight of an isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Kogyo Co., trade name "Coronate L"), and 100 parts by weight of toluene were mixed to prepare a composition for forming an elastic layer.

Acrylic copolymer (copolymer of ethyl acrylate, 2 ethylhexyl acrylate, and hydroxyethyl acrylate, ethyl acrylate structural unit: 2 ethylhexyl acrylate structural unit: hydroxyethyl acrylate structural unit: 70:30:5:6 ( weight ratio)) 100 parts by weight), 2 parts by weight of an isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Kogyo, trade name "Coronate L"), and a rosin phenol-based tackifying resin (manufactured by Sumitomo Bakelite, trade name "Sumiride Resin PR-12603") ') 15 parts by weight, 35 parts by weight of thermally expansible microspheres (manufactured by Matsumoto Yushi Seyaku, trade name "Matsumoto Microspar F-50"), and 100 parts by weight of toluene, mixed with a composition for forming a separate adhesive layer was prepared.

The composition for forming the pressure-sensitive adhesive layer was coated on one side of a PET film as a base layer (manufactured by Toray Corporation, trade name “Lumirer S10”, thickness 38 μm) to form an adhesive layer (thickness 10 μm) on the base layer. In addition, the composition for forming an elastic layer was coated on the other side of the PET film to form an elastic layer (thickness of 10 μm) on the base layer.

Separately, another pressure-sensitive adhesive layer (thickness of 35 µm) was formed by coating the other composition for forming the pressure-sensitive adhesive layer on another PET film. The other pressure-sensitive adhesive layer was transferred onto the elastic layer to obtain a pressure-sensitive adhesive sheet including a pressure-sensitive adhesive layer/base layer/elastic layer/other pressure-sensitive adhesive layer.

[Example 10]

Except having used the composition for adhesive layer formation obtained in Example 2 as the composition for adhesive layer formation, it carried out similarly to Example 9, and obtained the adhesive sheet.

[Example 11]

Except having used the composition for adhesive layer formation obtained in Example 3 as the composition for adhesive layer formation, it carried out similarly to Example 9, and obtained the adhesive sheet.

[Example 12]

Except having used the composition for adhesive layer formation obtained in Example 4 as the composition for adhesive layer formation, it carried out similarly to Example 9, and obtained the adhesive sheet.

[Comparative Example 1]

100 parts by weight of an acrylic copolymer (a copolymer of methyl acrylate, 2ethylhexyl acrylate, and acrylic acid, methyl acrylate structural unit: 2ethylhexyl acrylate structural unit: acrylic acid structural unit = 15:85:8 (weight ratio)), and an epoxy-based copolymer 3 parts by weight of a crosslinking agent (manufactured by Mitsubishi Gas Chemical, trade name "Tetrad C"), 10 parts by weight of a terpene phenol-based tackifying resin (manufactured by Yasuhara Chemical, trade name "YS Polyster S145"), and 100 parts by weight of toluene are mixed and a composition for forming an adhesive layer was prepared.

The composition for forming the pressure-sensitive adhesive layer was coated on one side of a polytetrafluoroethylene film (manufactured by Toray Corporation, trade name “Lumiror S10”, thickness 38 μm) as a base layer, and formed into a base layer and an adhesive layer (thickness 10 μm). The adhesive sheet comprised was obtained.

As is apparent from Table 1, the pressure-sensitive adhesive sheet of the present invention includes a pressure-sensitive adhesive layer having a contact angle of 15° or more with respect to 4-tert-butylphenyl glycidyl ether, that is, an adhesive having low affinity for the sealing resin. By providing a layer, there is little generation|occurrence|production of a standoff and the adhesive sheet which adhesive residue does not generate|occur|produce easily can be obtained.

10 adhesive layer
30 base layer
40 elastic layer
100, 200, 300 adhesive sheet

Claims (14)

A pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer,
The pressure-sensitive adhesive layer includes an acrylic pressure-sensitive adhesive,
The acrylic pressure-sensitive adhesive includes, as a base polymer, an acrylic polymer having an alkylester having 6 or more carbon atoms in a side chain,
In the acrylic polymer, the content ratio of the structural unit having an alkylester having 6 or more carbon atoms in the side chain is 50% by weight or more with respect to the total structural units constituting the acrylic polymer,
The contact angle of the surface of the pressure-sensitive adhesive layer with respect to 4-tert-butylphenyl glycidyl ether is 15° or more,
The adhesive force with respect to the polyethylene terephthalate in 23 degreeC of the said adhesive sheet is 0.5 N/20 mm or more,
The adhesive sheet used as a temporary fixing material at the time of sealing a some semiconductor chip collectively with sealing resin. According to claim 1,
Temporary when sealing a plurality of semiconductor chips collectively with a sealing resin whose sp value of the material constituting the pressure-sensitive adhesive in the pressure-sensitive adhesive layer is 7 (cal/cm 3 ) ^1/2 to 10 (cal/cm 3 ) ^1/2 An adhesive sheet used as a fixing material. 3. The method of claim 1 or 2,
The adhesive sheet used as a temporary fixing material at the time of sealing a some semiconductor chip collectively with sealing resin whose probe tack value of the said adhesive layer is 50 N/5 mmphi or more. 3. The method of claim 1 or 2,
The adhesive sheet used as a temporary fixing material at the time of sealing a some semiconductor chip collectively with the sealing resin in which the said adhesive layer further contains thermally expansible microsphere. 5. The method of claim 4,
The arithmetic surface roughness Ra of the said adhesive layer before heating the said thermally expansible microsphere is more than 0 nm and 500 nm or less The adhesive sheet used as a temporary fixing material at the time of sealing several semiconductor chips collectively with sealing resin. 3. The method of claim 1 or 2,
Under an environmental temperature of 23 ° C, the entire surface of the outer surface of the pressure-sensitive adhesive layer is bonded to a bakelite plate, aged for 30 minutes under an environmental temperature of 40 ° C., and then maintained for 2 hours while applying a load of 1.96 N, the bake The adhesive sheet used as a temporary fixing material at the time of sealing a some semiconductor chip collectively with the sealing resin whose shift|offset|difference with respect to a light plate is more than 0 mm and 0.5 mm or less. 3. The method of claim 1 or 2,
Further comprising a base layer,
The adhesive sheet used as a temporary fixing material at the time of sealing a some semiconductor chip collectively with the sealing resin in which the said adhesive layer is arrange|positioned on one side or both sides of the said base material layer. 8. The method of claim 7,
The adhesive sheet used as a temporary fixing material at the time of sealing a some semiconductor chip collectively with the sealing resin whose anchoring force of the said base material layer and the said adhesive layer is 6.0 N/19 mm or more. delete delete delete delete delete delete

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