TWI652324B - Adhesive sheet - Google Patents

Abstract

The present invention provides an adhesive sheet that has moderate adhesiveness to a sealing resin and a semiconductor wafer constituting a semiconductor package, can be easily peeled from the sealing resin and the semiconductor wafer, and can prevent paste residue during peeling.

The adhesive sheet of the present invention is an adhesive sheet provided with an adhesive layer, the contact angle of the surface of the adhesive layer with respect to 4-tert-butylbutyl glycidyl ether is 15° or more, and the adhesive sheet is at 23°C The adhesion to polyethylene terephthalate is above 0.5N/20mm.

Description

Adhesive sheet

The present invention relates to an adhesive sheet.

In recent years in pursuit of miniaturization of semiconductor devices, as a semiconductor packaging technology, a CSP (Chip Size/Scale Package) that forms a semiconductor package having the same size as a semiconductor device built-in has attracted attention. Among the CSPs, in particular, a semiconductor packaging technology for forming a small and highly integrated package, WLP (Wafer Level Package) is known. WLP is a technology that does not use a substrate, seals a plurality of semiconductor wafers in batches with a sealing resin, and then cuts and separates the semiconductor wafers to obtain a semiconductor package. In general, when sealing the semiconductor wafers in batches, in order to prevent the movement of the semiconductor wafers, a plurality of semiconductor wafers are temporarily fixed using a specific temporary fixing material, and the plurality of semiconductor wafers are sealed in batches on the temporary fixing material. Thereafter, when each semiconductor wafer is cut and separated (after batch sealing and before cutting and separating, or after cutting and separating), the temporary fixing material is peeled off from the structure including the sealing resin and the semiconductor wafer. As temporary fixing materials used in this way, adhesive sheets with low adhesiveness are often used.

However, if the previous adhesive sheet is used, there is a problem that when the structure including the sealing resin and the semiconductor wafer is peeled off, paste remains in the structure. In particular, the residual residue of the peripheral portion of the semiconductor wafer becomes conspicuous, and this residual residue becomes a problem that causes a decrease in yield.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2001-308116

[Patent Document 2] Japanese Patent Laid-Open No. 2001-313350

The present invention was made to solve the above-mentioned previous problems, and its object is to provide an adhesive sheet that has a moderate adhesiveness to a sealing resin and a semiconductor chip constituting a semiconductor package, and can be made from the sealing resin and semiconductor The wafer is easily peeled off, and the paste residue during peeling is not easily generated.

The adhesive sheet of the present invention is an adhesive sheet provided with an adhesive layer, the contact angle of the surface of the adhesive layer with respect to 4-tert-butylbutyl glycidyl ether is 15° or more, and the adhesive sheet is at 23°C The adhesion to polyethylene terephthalate is above 0.5N/20mm.

In one embodiment, the sp value of the material constituting the adhesive in the adhesive layer is 7 (cal/cm ³ ) ^1/2 to 10 (cal/cm ³ ) ^1/2 .

In one embodiment, the probe viscosity value of the adhesive layer is 50N/5mm the above.

In one embodiment, the adhesive layer includes an acrylic adhesive.

In one embodiment, the acrylic adhesive includes an acrylic polymer having an alkyl ester with a carbon number of 4 or more in the side chain as a base polymer.

In one embodiment, in the acrylic polymer, the content ratio of the structural unit having an alkyl ester having a carbon number of 4 or more in the side chain is 30% by weight or more relative to the total structural unit constituting the acrylic polymer .

In one embodiment, the adhesive layer includes a rubber-based adhesive.

In one embodiment, the adhesive layer includes a polysiloxane adhesive.

In one embodiment, the polysiloxane adhesive includes polysiloxane rubber and polysilicon Oxygen resin is used as the base polymer, and the weight ratio of the silicone rubber to the silicone resin (rubber: resin) is 100:0 to 100:220.

In one embodiment, the adhesive layer further includes thermally expandable microspheres.

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

In one embodiment, for the adhesive sheet of the present invention, the outer surface of the above adhesive layer is attached to the entire surface of the Bakelite board at an ambient temperature of 23° C. and at an ambient temperature of 40° C. After aging for 30 minutes, a load of 1.96 N is applied for 2 hours. At this time, the deviation of the adhesive sheet of the present invention with respect to the bakelite is 0.5 mm or less.

In one embodiment, the adhesive sheet of the present invention further includes a substrate layer, and the adhesive layer is disposed on one side or both sides of the substrate layer.

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

According to the present invention, by having an adhesive layer having a contact angle of 15° or more with respect to 4-tert-butylphenyl glycidyl ether, an adhesive sheet can be obtained which is suitable for the sealing resin and semiconductor constituting the semiconductor package The wafer has moderate adhesiveness, and can be easily peeled off from the sealing resin and the semiconductor wafer, and it is not easy to cause paste residue during peeling.

1‧‧‧Semiconductor chip

2‧‧‧Sealing resin

2'‧‧‧Composition

10‧‧‧adhesive layer

10'‧‧‧adhesive sheet

20‧‧‧Structure

30‧‧‧Base layer

40‧‧‧Elastic layer

100, 200, 300 ‧‧‧ adhesive sheet

FIG. 1(a) is a diagram illustrating an example when the previous adhesive sheet is used for manufacturing a semiconductor package, and FIG. 1(b) is an example when the adhesive sheet of the present invention is used for manufacturing a semiconductor package. Picture.

2(a) and (b) are schematic cross-sectional views of an adhesive sheet according to an 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. Summary of adhesive sheet

The adhesive sheet of the present invention has an adhesive layer. The adhesive sheet of the present invention may be composed of only the adhesive layer, or may be provided with any appropriate layer in addition to the adhesive layer. Examples of the layer other than the adhesive layer include a base material layer that can function as a support, a separator that is releasably arranged on the adhesive layer, and the like. Furthermore, in addition to the above-mentioned adhesive layer, another adhesive layer may be provided. The other adhesive layer only needs to be a well-known structure.

The adhesive sheet of the present invention has an adhesive force to polyethylene terephthalate at 23°C of preferably 0.5 N/20 mm or more, more preferably 0.5 N/20 mm to 20 N/20 mm, and further preferably 0.5 N/ 20mm~15N/20mm. In one embodiment, the adhesive layer of the adhesive sheet of the present invention has reduced adhesion due to heating or light irradiation. In this case, the above-mentioned adhesive force before the decrease of the adhesive force is 2.5N/20mm~20N/20mm. In addition, in this specification, the "adhesion to polyethylene terephthalate" refers to the bonding of an adhesive sheet (width 20 mm × width) on a polyethylene terephthalate film (thickness 25 μm) The adhesive layer (length of 100mm) (lamination conditions: 2kg roller, 1 round trip), after being left at an ambient temperature of 23°C for 30 minutes, the sample was subjected to a tensile test (peeling speed: 300mm/min, peeling) Angle 180°) to determine the adhesion.

The adhesive force of the adhesive sheet of the present invention to a silicon wafer (thickness 500 μm) at 23° C. is preferably 0.1 N/20 mm to 4 N/20 mm, more preferably 0.15 N/20 mm to 3 N/20 mm, and further preferably 0.2 N/20mm~2/20mm. Within such a range, an adhesive sheet can be obtained that takes into account the adhesion to the semiconductor wafer and the peelability. Adhesion to silicon wafers can also be measured using the same method as above for "adhesion to polyethylene terephthalate".

The adhesive strength of the adhesive sheet of the present invention to an epoxy resin sheet at 23°C is preferably 0.1N/20mm~5N/20mm, more preferably 0.3N/20mm~4N/20mm, and further preferably 0.5N /20mm~3/20mm. Within such a range, it is possible to suppress the residue of the paste when peeling off from the sealing resin (details will be described later). The adhesion to the epoxy resin film can also be improved by the same method as the above "adhesion to polyethylene terephthalate". OK. In addition, as the above-mentioned epoxy-based resin film, for example, a film composed of the sealing resin described in the evaluation of the "stand off suppression effect" of Examples can be used.

The outer surface of the adhesive layer of the adhesive sheet of the present invention (width 10mm × length 150mm) is attached to the entire surface of the bakelite board (width 10mm × length 125mm) at an ambient temperature of 23℃, and the ambient temperature of 40℃ After aging for 30 minutes, and then applying a load of 1.96 N for 2 hours, the deviation of the adhesive sheet relative to the bakelite is preferably 0.5 mm or less, and more preferably 0.4 mm or less. In addition, the "offset of the adhesive sheet relative to the bakelite" here refers to the amount of movement of the adhesive sheet from the initial state based on the state before curing (initial state). The above-mentioned adhesive sheet with a small offset is an adhesive sheet that is not likely to cause cohesive failure of the adhesive layer. Such an adhesive sheet is essentially an adhesive sheet that is not likely to cause residual paste. If it is such an adhesive sheet, the effect of this invention will become remarkable. The adhesive layer that is less susceptible to cohesive failure can be formed, for example, by using the above-mentioned acrylic adhesive (preferably an adhesive containing a cross-linked acrylic polymer as a base polymer) as the adhesive for forming the adhesive layer. In addition, as the adhesive, a rubber-based adhesive is used. In more detail, a base polymer (rubber) containing a rubber-based adhesive, a polyolefin containing a hydroxyl group, and a hydroxyl group capable of reacting with the hydroxyl group of the hydroxy polyolefin are used The rubber-based adhesive (Rub1) of the cross-linking agent, and the blending amount of the hydroxyl group-containing polyolefin and the cross-linking agent are appropriately adjusted, whereby an adhesive layer that is less likely to cause cohesive failure can be formed. The details will be explained later.

The thickness of the adhesive sheet of the present invention is preferably 3 μm to 300 μm, more preferably 5 μm to 150 μm, and still more preferably 10 μm to 100 μm.

B. Adhesive layer

The contact angle of the surface of the adhesive layer with respect to 4-tert-butylphenyl glycidyl ether is 15° or more, more preferably 20° or more, further preferably 30° to 100°, and particularly preferably 40° to 60 °.

The adhesive layer of the adhesive sheet of the present invention is adjusted to the affinity of the sealing resin (for example, epoxy resin) used when sealing the semiconductor wafer and the monomer component constituting the sealing resin. Specifically, the above-mentioned adhesive layer can be applied to the sealing resin (and semiconductor wafer) Within the range of proper adhesion, the affinity is adjusted in such a way that the affinity decreases. The contact angle of the adhesive layer whose affinity is appropriately adjusted with respect to 4-third butylphenyl glycidyl ether shows the above range. By adjusting the affinity for the sealing resin and the monomer components constituting the sealing resin in this way, an adhesive sheet with little paste residue can be obtained, more specifically, the following adhesive sheet can be obtained: In the case where the structure (FIG. 1) of the resin (or the precursor monomer of the resin) that seals the semiconductor is peeled off afterwards, the composition of the adhesive layer attached to the structure can be reduced. The mechanism for reducing the residue of the paste by using the adhesive sheet of the present invention can be considered as follows.

FIG. 1(a) shows an example when the previous adhesive sheet 10' is used for manufacturing a semiconductor package. The adhesive sheet 10' has an adhesive layer, and the outer surface of the adhesive layer serves as a bonding surface. Previously, in the manufacture of semiconductor packages (CSP), first, the semiconductor wafer 1 (a-i) was bonded to the adhesive sheet 10'. Thereafter, the semiconductor wafer 1 is sealed, and a composition 2′ (a-ii) containing a monomer that becomes a precursor of the sealing resin 2 is applied, and thereafter, the composition 2′ is cured (a-iii). Furthermore, as the above-mentioned composition, for example, a composition containing a naphthalene type bifunctional epoxy resin (epoxy equivalent: 144) can be used. Then, before severing or separating the semiconductor wafers or after severing and separating (before severing and separating in the illustrated example), the adhesive sheet 10' is peeled off from the structure 20 including the semiconductor wafer 1 and the sealing resin 2 (a -iv). In the case of using the previous adhesive sheet, it is easy to cause paste residue during peeling. Especially in the peripheral portion of the semiconductor wafer 1, a paste residue is remarkably observed. The inventors of the present invention have found that in the case where the previous adhesive sheet 10' is used, the adhesive layer of the adhesive sheet 10' during peeling is raised to surround the bottom of the semiconductor wafer 1, and the adhesive sheet during peeling In the adhesive layer of 10', a step difference (hereinafter also referred to as a gap height) caused by the bottom edge of the semiconductor wafer 1 occurs. It is considered that since the stress originating from the semiconductor wafer 1 is concentrated in the gap height portion, cohesive failure of the adhesive layer occurs, and as a result, the above-mentioned paste remains.

FIG. 1(b) shows an example when the adhesive sheet 10 of the present invention is used for manufacturing a semiconductor package. The adhesive sheet 10 has an adhesive layer, and the outer surface of the adhesive layer serves as a bonding surface. In FIG. 1(b), except for changing the adhesive sheet, a structure 20 including the semiconductor wafer 1 and the sealing resin 2 is formed on the adhesive sheet 10 by the same operation as shown in FIG. 1(a). Thereafter, the adhesive sheet 10 is peeled off. In the case of using the adhesive sheet 10 of the present invention, the height of the gap generated in the adhesive sheet 10 is extremely small (or not generated), and the paste residue is suppressed.

It can be considered that in the previous adhesive sheet 10', the adhesive layer component was transferred to the composition containing the monomer that became the precursor of the sealing resin 2 or the sealing resin, and as a result, the resin layer of the adhesive sheet 10' It bulges in such a way as to surround the bottom of the semiconductor wafer 1 to produce a gap height. Furthermore, the presence or absence of component transfer can be confirmed by spectral analysis using FT-IR or the like. On the other hand, it can be considered that, in the present invention, the affinity of the adhesive layer for the sealing resin used for sealing the semiconductor wafer and the monomer component constituting the sealing resin is adjusted, so the component transfer as described above is suppressed, The gap height becomes extremely small (or does not occur), and as a result, paste residue is suppressed. In addition, in the following description, in this specification, the sealing resin used when sealing a semiconductor wafer and the monomer components constituting the sealing resin are collectively referred to as a sealing material.

The adhesive layer contains an adhesive. The sp value of the material (polymer) constituting the adhesive is preferably 7 (cal/cm ³ ) ^1/2 to 10 (cal/cm ³ ) ^1/2 , more preferably 7 (cal/cm ³ ) ^1/2 ~9.1 (cal/cm ³ ) ^1/2 , and further preferably 7 (cal/cm ³ ) ^1/2 to 8 (cal/cm ³ ) ^1/2 . Within such a range, it is possible to form an adhesive layer that has appropriate adhesiveness, has low affinity with the sealing material, and is not likely to have a gap height. Adhesive sheets with such an adhesive layer are less likely to produce paste residue. In addition, the material constituting the adhesive here refers to the base polymer contained in the adhesive (in the case of cross-linking, the base polymer after cross-linking), rubber (in the case of cross-linking, after cross-linking) Rubber), adhesion-imparting agents and other polymers. In the present invention, the sp of at least the base polymer (the base polymer after crosslinking in the case of crosslinking) or the rubber (the rubber after crosslinking in the case of crosslinking) as the main component of the adhesive is preferably sp The value is in the above range.

In one embodiment, the surface of the above-mentioned adhesive layer is brought into contact with 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, and placed in an environment of 50°C for 2 hours for the adhesive On the surface, when the absorbance of the peak derived from glycidyl group is measured by FT-IR measurement, the absorbance of the peak derived from glycidyl group is higher than the absorbance of the peak derived from glycidyl group of the initial adhesive layer. It is preferably 1.3 or less, more preferably 1.1 or less, and still more preferably 1.05 or less. Furthermore, the so-called "initial adhesive layer" refers to the adhesive layer before contact with 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane. In another embodiment, the surface of the adhesive layer is brought into contact with 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, and placed in an environment of 50°C for 2 hours to perform the adhesion In the case of FT-IR measurement of the surface of the agent (for example, the attenuation total reflection method (ATR method)), the absorbance at the wave number (near 850 cm ^-1 ) of the peak derived from the glycidyl group is measured from the initial adhesive layer. The increase amount is preferably 0.3 or less, and more preferably 0.1 or less. Here, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane is an epoxy compound that can become a resin material for sealing semiconductor wafers. As long as an adhesive layer is formed that does not easily transfer the epoxy compound as described above even when in contact with the epoxy compound, an adhesive sheet that is less likely to generate gap heights and has less paste residue even when used in the manufacture of semiconductor packages can be obtained .

The thickness of the 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, still more preferably 10 μm to 50 μm. When the adhesive layer contains heat-expandable microspheres as described below, the thickness of the adhesive layer is preferably 3 μm to 300 μm, more preferably 5 μm to 150 μm, and further preferably 10 μm to 100 μm. Within such a range, an adhesive layer having excellent surface smoothness and excellent adhesion can be formed. When the adhesive layer does not contain thermally expandable microspheres, the thickness of the adhesive layer is preferably 50 μm or less, more preferably 1 μm to 50 μm, and further preferably 5 μm to 30 μm.

The elastic modulus of the adhesive layer measured by the nanoindentation method at 25°C is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, and still more preferably 0.1 MPa to 10 MPa. Within such a range, an adhesive sheet having an appropriate adhesive force as an adhesive sheet that can be used in the manufacture of semiconductor packages can be obtained. The so-called nano-indentation method The modulus of elasticity refers to the continuous determination of the load and depth of the indenter when the indenter is pressed into the sample during loading and unloading. The elastic modulus is obtained from the obtained load load-indentation depth curve number. In this specification, the so-called elastic modulus measured by the nanoindentation method refers to the load: 1mN, load. Unloading speed: 0.1mN/s, holding time: 1s as the measurement condition, the elastic modulus measured as described above.

The tensile elastic modulus of the adhesive layer at 25°C is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, and still more preferably 0.1 MPa to 10 MPa. Within such a range, an adhesive sheet having an appropriate adhesive force as an adhesive sheet that can be used in the manufacture of semiconductor packages can be obtained. In addition, the tensile elastic modulus can be measured according to JIS K 7161:2008.

The probe viscosity value of the above adhesive layer is preferably 50N/5mm Above, more preferably 75N/5mm Above, and more preferably 100N/5mm the above. Within such a range, the adherence of the adherend is excellent. For example, when the semiconductor wafer is temporarily fixed, unnecessary positional deviation of the semiconductor wafer can be prevented. The measuring method of the probe viscosity value is as follows.

<adhesive>

As the adhesive constituting the above-mentioned adhesive layer, any suitable adhesive can be used as long as the effects of the present invention can be obtained. It is preferable to use an adhesive containing a base polymer having an sp value in the above range. Examples of the adhesive include acrylic adhesives, rubber adhesives, and silicone adhesives. Among them, acrylic adhesives can be preferably used. In addition, an active energy ray hardening type adhesive can also be used as the adhesive.

(Acrylic adhesive)

As the acrylic adhesive, for example, acrylic acid using an acrylic polymer (homopolymer or copolymer) using one or more alkyl (meth)acrylate as a monomer component as a base polymer can be cited. Department of adhesives.

The acrylic polymer preferably has an alkyl ester having a carbon number of 4 or more in the side chain, more preferably an alkyl ester having a carbon number of 6 or more in the side chain, and further preferably has a carbon number of 8 in the side chain. The above alkyl esters are particularly preferably alkyl esters having 8 to 20 carbon atoms in the side chain, and most preferably alkyl esters having 8 to 18 carbon atoms in the side chain. If an acrylic polymer having a long side chain is used, an adhesive layer with low affinity with the sealing material can be formed. In the above acrylic polymer, the content ratio of the structural unit having an alkyl ester having a carbon number of 4 or more in the side chain relative to the total structural unit constituting the acrylic polymer is preferably 30% by weight or more, more preferably 50% by weight or more, further preferably 70% by weight to 100% by weight, particularly preferably 80% by weight to 100% by weight. Within such a range, an adhesive layer with low affinity with the sealing material can be formed.

The acrylic adhesive may include a plurality of acrylic polymers, and the content ratio of the acrylic polymer having an alkyl ester having a carbon number of 4 or more in the side chain is preferably 100 parts by weight of the entire acrylic polymer. 30 to 100 parts by weight, more preferably 70 to 100 parts by weight.

Specific examples of the above-mentioned alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, Butyl (meth)acrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, third butyl (meth)acrylate, amyl (meth)acrylate, (meth)acrylic acid Hexyl ester, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, (A Group) isononyl acrylate, decyl (meth)acrylate, isdecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, (meth) Tridecyl acrylate, myristyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate , Octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate and other C1-20 alkyl (meth) acrylates. Among them, preferred are alkyl (meth)acrylates having a linear or branched alkyl group having a carbon number of 4 to 20 (more preferably 6 to 20, particularly preferably 8 to 18), more preferably 2-ethylhexyl (meth)acrylate.

The acrylic polymer may be modified for cohesive strength, heat resistance, crosslinkability, etc., and may contain units corresponding to other monomer components copolymerizable with the alkyl (meth)acrylate as required. Examples of such monomer components include acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, butenoic acid, and the like. Monomers; anhydride monomers such as maleic anhydride and itaconic anhydride; hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxy (meth)acrylate Hydroxy-containing monomers such as hexyl ester, hydroxyoctyl (meth)acrylate, hydroxydecyl (meth)acrylate, hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl) methyl methacrylate ; Styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl (meth)acrylate, (Meth) acryloxynaphthalenesulfonic acid and other monomers containing sulfonic acid groups; (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl (methyl ) (N-substituted) amide monomers such as acrylamide, N-methylol (meth)acrylamide, N-methylolpropane (meth)acrylamide; (meth)acrylic acid amine groups Aminoalkyl (meth)acrylate monomers such as ethyl, N,N-dimethylaminoethyl (meth)acrylate, tert-butylaminoethyl (meth)acrylate; (methyl ) Alkoxyalkyl (meth)acrylate monomers such as methoxyethyl acrylate, ethoxyethyl (meth)acrylate; N-cyclohexyl maleimide, N-isopropyl Maleic diimide-based monomers such as cis-butene diimide, N-lauryl maleimide diimide, N-phenyl maleimide diimide; N-methyl icon Acetimide, N-ethyleconimide, N-butyleconimide, N-octylecantimide, N-2-ethylhexyleconimide, N-ring Iconimide-based monomers such as hexyl yconamide and N-lauryl yconamide; N-(meth)acryl oxymethylene succinimide, N-(methyl) Acryloyl-6-oxyhexamethylene succinimide, N-(meth)acryloyl-8-oxyoctamethylene succinimide and other succinimide-based monomers; vinyl acetate Ester, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperidine Vinylpyridine , Vinylpyrrole, vinylimidazole, vinyl Azole, vinyl Vinyl monomers such as porphyrin, N-vinylcarboxamides, styrene, α -methylstyrene, N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile ; Acrylic monomers containing epoxy groups such as glycidyl (meth)acrylate; polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxypolyethylene glycol (methyl ) Acrylic esters, methoxy polypropylene glycol (meth)acrylate and other glycol-based acrylate monomers; tetrahydrofurfuryl (meth)acrylate, fluoro (meth)acrylate, polysiloxane (meth)acrylic acid Acrylic ester monomers such as esters having heterocycles, halogen atoms, silicon atoms, etc.; hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di( Methacrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, di Multifunctional monomers such as pentaerythritol hexa(meth)acrylate, epoxy acrylate, polyester acrylate, urethane acrylate; olefin monomers such as isoprene, butadiene, isobutylene; vinyl ether, etc. Vinyl ether monomers, etc. These monomer components can be used individually or in combination of 2 or more types. Among the above, a carboxyl group-containing monomer (preferably acrylic acid) or a hydroxyl group-containing monomer (preferably hydroxyethyl (meth)acrylate) is more preferable. The content of the structural unit derived from the carboxyl group-containing monomer relative to the total structural unit constituting the acrylic polymer is preferably 0.1% by weight to 10% by weight, more preferably 0.5% by weight to 5% by weight, and particularly preferably 1 Weight%~4weight%. In addition, the content of the structural unit derived from the hydroxyl group-containing monomer relative to the total structural unit constituting the acrylic polymer is preferably 0.1% by weight to 20% by weight, more preferably 0.5% by weight to 10% by weight, and particularly preferably It is 1% to 7% by weight.

The acrylic adhesive may contain any appropriate additives as needed. Examples of the additives include crosslinking agents, adhesion-imparting agents, plasticizers (for example, trimellitate-based plasticizers, pyromellitate-based plasticizers, etc.), pigments, dyes, and fillers. Agents, anti-aging agents, conductive materials, antistatic agents, ultraviolet absorbers, light stabilizers, peeling regulators, softeners, surfactants, flame retardants, antioxidants, etc.

Examples of the cross-linking agent included in the acrylic adhesive include isocyanate-based cross-linking agents, epoxy-based cross-linking agents, melamine-based cross-linking agents, and peroxide-based cross-linking agents. In addition, urea-based Crosslinking agent, metal alkoxide-based crosslinking agent, metal chelate-based crosslinking agent, metal salt-based crosslinking agent, carbodiimide-based crosslinking agent, An oxazoline-based crosslinking agent, an aziridine-based crosslinking agent, an amine-based crosslinking agent, etc. Among them, isocyanate-based crosslinking agents or epoxy-based crosslinking agents are preferred.

Specific examples of the isocyanate-based crosslinking agent included in the acrylic adhesive include: lower aliphatic polyisocyanates such as butyl diisocyanate and hexamethylene diisocyanate; cyclopentyl diisocyanate Cyclohexyl diisocyanate, isophorone diisocyanate and other alicyclic isocyanates; 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate and other aromatic isocyanates; Trimethylolpropane/toluene diisocyanate terpolymer adduct (manufactured by Nippon Polyurethane Industry, trade name "CORONATE L"), trimethylolpropane/hexamethylene diisocyanate terpolymer adduct (Nippon Isocyanate adducts such as Pocyurethane Industry Co., Ltd. trade name "CORONATE HL"), isocyanurate body of hexamethylene diisocyanate (Nippon Pocyurethane Industry Co., Ltd. trade name "CORONATE HX"), etc. The content of the isocyanate-based crosslinking agent can be set to any appropriate amount according to the desired adhesive force, and is typically 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the base polymer. Parts by weight.

Examples of the epoxy-based crosslinking agent included in the acrylic adhesive include N,N,N',N'-tetraglycidyl-m-xylylenediamine, diglycidylaniline, and 1, 3-bis(N,N-glycidylaminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name "TETRAD-C"), 1,6-hexanediol diglycidyl ether (Kyoeisha Chemical company, trade name "EPOLIGHT 1600"), neopentyl glycol diglycidyl ether (produced by Kyoeisha Chemical Company, trade name "EPOLIGHT 1500NP"), ethylene glycol diglycidyl ether (produced by Kyoeisha Chemical Company) , Trade name "EPOLIGHT 40E"), propylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Company, trade name "EPOLIGHT 70P"), polyethylene glycol diglycidyl Ether (manufactured by Nippon Oil & Fats Corporation, trade name "EPIOL E-400"), polypropylene glycol diglycidyl ether (manufactured by Nippon Oils and Fats Corporation, trade name "EPIOL P-200"), sorbitol polyglycidyl ether (manufactured by Nagase ChemteX Corporation) , Trade name "DENACOL EX-611"), glycerin polyglycidyl ether (manufactured by Nagase ChemteX, brand name "DENACOL EX-314"), pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether (manufactured by Nagase ChemteX, Trade name "DENACOL EX-512"), sorbitan polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycidyl adipate, diglycidyl phthalate, triglycidyl- Tris (2-hydroxyethyl) isocyanurate, resorcinol diglycidyl ether, bisphenol-S-diglycidyl ether, epoxy resins having two or more epoxy groups in the molecule, etc. The content of the epoxy-based crosslinking agent can be set to any appropriate amount according to the desired adhesive force, and is typically 0.01 to 10 parts by weight, more preferably 0.03 to about 100 parts by weight with respect to the base polymer. 5 parts by weight.

As the adhesion-imparting agent included in the acrylic adhesive, any appropriate adhesion-imparting agent can be used. As the adhesion-imparting agent, for example, an adhesion-imparting resin can be used. Specific examples of the adhesion-imparting resin include rosin-based adhesion-imparting resins (for example, unmodified rosin, modified rosin, rosin phenol-based resins, and rosin ester-based resins), and terpene-based adhesion-imparting resins (for example, Terpene resins, terpene phenol resins, styrene modified terpene resins, aromatic modified terpene resins, hydrogenated terpene resins), hydrocarbon-based adhesion-imparting resins (for example, aliphatic hydrocarbon resins, Aliphatic cyclic hydrocarbon resin, aromatic hydrocarbon resin (for example, styrene resin, xylene resin, etc.), aliphatic. aromatic petroleum resin, aliphatic. alicyclic petroleum resin, hydrogenated hydrocarbon resin , Coumarone-based resin, coumarone-indene-based resin, etc.), phenol-based adhesion-imparting resin (for example, alkylphenol-based resin, xylene formaldehyde-based resin, soluble phenolic resin, novolac, etc.), ketone-based adhesion Resin-imparting, polyamide-based adhesion-imparting resin, epoxy-based adhesion-imparting resin, elastic system-adhesive-imparting resin, etc. Among them, rosin-based adhesion-imparting resins, terpene-based adhesion-imparting resins or hydrocarbon-based adhesion-imparting resins (styrene-based resins, etc.) are preferable. The adhesion-imparting agent can be used alone or in combination of two Use more than one species. The added amount of the adhesion-imparting agent is preferably 5 parts by weight to 100 parts by weight, and more preferably 10 parts by weight to 50 parts by weight with respect to 100 parts by weight of the base polymer.

It is preferable to use a resin having a high softening point or a high glass transition temperature (Tg) as the adhesion-imparting resin. If a resin with a high softening point or a high glass transition temperature (Tg) is used, an adhesive layer that can exhibit high adhesion can be formed even in a high-temperature environment (for example, a high-temperature environment such as processing during semiconductor wafer sealing) . The softening point of the adhesion-imparting agent is preferably 100°C to 180°C, more preferably 110°C to 180°C, and still more preferably 120°C to 180°C. The glass transition temperature (Tg) of the adhesion-imparting agent is preferably 100°C to 180°C, more preferably 110°C to 180°C, and still more preferably 120°C to 180°C.

It is preferable to use a low polarity adhesion-imparting resin as the above-mentioned adhesion-imparting resin. If a low polarity adhesion-imparting resin is used, an adhesive layer with low affinity with the sealing material can be formed. Examples of low polarity adhesion-imparting resins include aliphatic hydrocarbon resins, aliphatic cyclic hydrocarbon resins, aromatic hydrocarbon resins (for example, styrene resins, xylene resins, etc.), and aliphatics. Aromatic petroleum resin, aliphatic. The hydrocarbon-based adhesion of alicyclic petroleum resins and hydrogenated hydrocarbon resins gives resins. Among them, an adhesion-imparting agent with a carbon number of 5 to 9 is preferred. Such an adhesion-imparting agent has low polarity, and has excellent compatibility with acrylic polymers, does not cause phase separation in a wide temperature range, and can form an adhesive layer with excellent stability.

The acid value of the adhesion-imparting resin is preferably 40 or less, more preferably 20 or less, and still more preferably 10 or less. Within such a range, an adhesive layer with low affinity with the sealing material can be formed. The hydroxyl value of the adhesion-imparting resin is preferably 60 or less, more preferably 40 or less, and still more preferably 20 or less. Within such a range, an adhesive layer with low affinity with the sealing material can be formed.

(Rubber-based adhesive)

As the above-mentioned rubber-based adhesive, as long as the effect of the present invention can be obtained, any appropriate adhesive can be used. As the above rubber-based adhesive, for example, it is preferably used as follows Substances used as base polymers for rubber-based adhesives: natural rubber; polyisoprene rubber, butadiene rubber, styrene-butadiene (SB) rubber, styrene-isoprene (SI) rubber, benzene Ethylene-isoprene-styrene block copolymer (SIS) rubber, styrene-butadiene-styrene block copolymer (SBS) rubber, styrene-ethylene-butene-styrene block copolymer (SEBS) rubber, styrene-ethylene-propylene-styrene block copolymer (SEPS) rubber, styrene-ethylene-propylene block copolymer (SEP) rubber, recycled rubber, butyl rubber, polyisobutylene rubber, or Synthetic rubber such as such modified body. The sp value of the base polymer (rubber) is low, and if the base polymer is used, an adhesive layer with low affinity with the sealing material can be formed.

As the base polymer constituting the rubber-based adhesive, polyisobutylene rubber, polyisoprene rubber, or butyl rubber is particularly preferably used. If such rubber is used, an adhesive layer having excellent semiconductor wafer retention at room temperature and excellent peelability can be formed. In addition, an adhesive layer having low affinity with the sealing material can be formed.

As the base polymer constituting the above rubber-based adhesive, styrene-ethylene-propylene block copolymer (SEP) rubber and styrene-ethylene-butylene-styrene block copolymer (SEBS) can also be preferably used Rubber, styrene-isoprene-styrene block copolymer (SIS) rubber, styrene-butadiene-styrene block copolymer (SBS) rubber, propylene rubber. If such rubber is used, even in a high-temperature environment (for example, in a high-temperature environment such as processing during sealing of a semiconductor wafer), an adhesive layer that can exhibit high adhesion can be formed. In the base polymer (rubber) having a structural unit derived from styrene, the content ratio of the structural unit derived from styrene is preferably 15% by weight or more relative to the total structural unit in the base polymer.

The rubber-based adhesive may contain any appropriate additives as needed. Examples of the additives include crosslinking agents, vulcanizing agents, adhesion-imparting agents, plasticizers, pigments, dyes, fillers, anti-aging agents, conductive materials, antistatic agents, ultraviolet absorbers, light stabilizers, and peeling agents. Conditioner, softener, surfactant, flame retardant, anti-oxidation Agent.

As the adhesion-imparting agent contained in the rubber-based adhesive, any appropriate adhesion-imparting agent can be used. As the adhesion-imparting agent, for example, an adhesion-imparting resin can be used. Specific examples of the adhesion-imparting resin include rosin-based adhesion-imparting resins, rosin derivative resins, petroleum-based resins, terpene-based resins, and ketone-based resins. The added amount of the adhesion-imparting agent is preferably 5 parts by weight to 100 parts by weight, and more preferably 10 parts by weight to 50 parts by weight with respect to 100 parts by weight of the base polymer.

Examples of the rosin-based resin included in the rubber-based adhesive include gum rosin, wood rosin, and tall rosin. As the rosin-based resin, a stabilized rosin obtained by disproportionation or hydrogenation of any appropriate rosin can also be used. Furthermore, as the rosin-based resin, a polymerized rosin which is a polymer (typically a dimer) of any suitable rosin can be used, and any suitable rosin can be modified (for example, modified with an unsaturated acid) ) The modified rosin obtained.

Examples of the rosin derivative resin included in the rubber-based adhesive include esterified products of the rosin-based resin, phenol-modified rosin-based resin, and esterified phenol-modified rosin-based resin.

Examples of the petroleum-based resin contained in the rubber-based adhesive include aliphatic petroleum resins, aromatic petroleum resins, copolymerized petroleum resins, alicyclic petroleum resins, and hydrides of these.

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

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

Examples of the crosslinking agent included in the rubber-based adhesive include isocyanate-based crosslinking agents. Examples of the vulcanizing agent contained in the rubber-based adhesive include: Thiuram-based vulcanizing agent, quinone-based vulcanizing agent, quinone dioxime-based vulcanizing agent, etc. If the rubber-based adhesive contains a cross-linking agent and/or a vulcanizing agent, it is possible to form an adhesive layer with high cohesiveness and less likely to cause paste residue. The total content of the crosslinking agent and the vulcanizing agent is typically 0.1 to 20 parts by weight, and more preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the base polymer.

In one embodiment, a rubber-based adhesive (Rub1) containing the above-mentioned base polymer (rubber), a hydroxyl group-containing polyolefin, and a crosslinking agent a that can react with the hydroxyl group of the hydroxyl polyolefin is used. In this rubber-based adhesive, the base polymer is not directly cross-linked, but the base polymer and the cross-linked hydroxyl group-containing polyolefin are entangled with each other to perform so-called pseudo cross-linking. As a result, it is possible to form an adhesive layer with high cohesiveness and less likely to cause paste residue. As the base polymer (rubber) used in this embodiment, the above-mentioned synthetic rubber is preferably used. In addition, as the crosslinking agent used in this embodiment, an isocyanate-based crosslinking agent is preferably used.

The compounding amount of the hydroxyl group-containing polyolefin is preferably 0.5 parts by weight or more, and more preferably 1.0 part by weight with respect to a total of 100 parts by weight of the base polymer (rubber), the hydroxyl group-containing polyolefin, and the cross-linking agent a. More than. Within such a range, an adhesive layer with high cohesiveness can be formed. In addition, when the adhesive sheet has a base material layer, the adhesiveness (grip strength) of the base material layer and the adhesive layer can be improved. That is, if the blending amount of the hydroxyl group-containing polyolefin is within the above range, an adhesive sheet with little paste residue can be obtained.

The compounding amount of the crosslinking agent a is preferably 0.5 parts by weight or more, and more preferably 1.0 part by weight with respect to a total of 100 parts by weight of the base polymer (rubber), the hydroxyl group-containing polyolefin and the crosslinking agent a. the above. Within such a range, an adhesive layer with high cohesiveness can be formed. In addition, when the adhesive sheet has a base material layer, the adhesiveness (grip strength) of the base material layer and the adhesive layer can be improved. That is, if the blending amount of the cross-linking agent a is within the above range, an adhesive sheet with little paste residue can be obtained.

As the above-mentioned hydroxyl group-containing polyolefin, it is preferable to use a phase equivalent to the above-mentioned synthetic rubber Resin with excellent solubility. Examples of the hydroxyl group-containing polyolefin include polyethylene polyols, polypropylene polyols, polybutadiene polyols, hydrogenated polybutadiene polyols, polyisoprene polyols, and hydrogenated polyisoprene. Diene polyol, etc. From the viewpoint of compatibility with the above-mentioned synthetic rubber, among them, hydrogenated polyisoprene polyol, polyisoprene polyol, and polybutadiene polyol are preferable.

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. The number average molecular weight can be determined according to ASTM D2503.

The hydroxyl value (mgKOH/g) of the hydroxyl group-containing polyolefin is preferably 5 to 95, and more preferably 10 to 80. The hydroxyl value can be measured according to JIS K1557:1970.

(Polysiloxane Adhesive)

As the above-mentioned polysiloxane-based adhesive, as long as the effect of the present invention can be obtained, any appropriate adhesive can be used. As the above-mentioned polysiloxane-based adhesive, for example, a polysiloxane-based adhesive containing a polysiloxane rubber or a polysiloxane resin containing organic polysiloxane as a base polymer can be preferably used. As the base polymer constituting the silicone adhesive, a base polymer obtained by crosslinking the above-mentioned silicone rubber or silicone resin can also be used. In addition, in this specification, the so-called "polysiloxane" refers to a polymer in which two organosiloxanes (unit D) as main components are connected into a linear chain (for example, viscosity 1000 Pa.s); the so-called "polysilicone" "Oxygen resin" refers to a polymer composed of three organic hemisiloxanes (M units) and silicates (Q units) as the main components ("adhesive (film. tape) material design and functional endowment)" , Technical Information Association, published on September 30, 2009).

Examples of the polysiloxane rubber include organic polysiloxanes containing dimethylsiloxane as a structural unit. A functional group (for example, vinyl group) may be introduced into the organic polysiloxane as needed. The weight average molecular weight of the organic polysiloxane is preferably 100,000-1,000,000, and more preferably 150,000-500,000. The weight average molecular weight can be measured by GPC (solvent: THF).

Examples of the polysiloxane resin include organic polysiloxane containing at least one structural unit selected from the group consisting of R ₃ SiO _1/2 structural unit, SiO ₂ structural unit, RSiO _3/2 structural unit, and R ₂ SiO structural unit. Alkanes (R is a monovalent hydrocarbon group or hydroxyl group).

The above-mentioned silicone rubber and silicone resin can be used in combination. The weight ratio of silicone rubber to silicone resin in the silicone adhesive (rubber: resin) is preferably 100:0 to 100:220, more preferably 100:0 to 100:180, and further preferably 100:10~100:100. Silicone rubber and silicone resin can be included in the silicone adhesive as a simple mixture, or can be included in the silicone adhesive in the form of partial condensation of silicone rubber and silicone resin In the agent. The rubber:resin ratio can also be obtained from the ratio of the Q unit (resin) to the D unit (rubber) obtained by measuring the composition of the silicone adhesive using ²⁹ Si-NMR.

The above-mentioned polysiloxane adhesive may contain any appropriate additives as needed. Examples of the additives include crosslinking agents, vulcanizing agents, adhesion-imparting agents, plasticizers, pigments, dyes, fillers, anti-aging agents, conductive materials, antistatic agents, ultraviolet absorbers, light stabilizers, and peeling agents. Regulators, softeners, surfactants, flame retardants, antioxidants, etc.

It is preferable that the polysiloxane adhesive contains a crosslinking agent. Examples of the crosslinking agent include a siloxane-based crosslinking agent and a peroxide-based crosslinking agent. As the peroxide-based crosslinking agent, any appropriate crosslinking agent can be used. Examples of the peroxide-based crosslinking agent include benzoyl peroxide, tert-butyl peroxybenzoate, and dicumyl peroxide. Examples of the silicone-based crosslinking agent include polyorganohydrogensiloxane. 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, or a halogenated alkyl group as a functional group bonded to a silicon atom.

(Active energy ray hardening adhesive)

As the above-mentioned adhesive, an active energy ray-curable adhesive that can be cured (high elastic modulus) by irradiation with active energy rays can also be used. If using active energy The radiation-hardening adhesive can obtain an adhesive sheet that is low in elasticity and high in flexibility and excellent in handling when attached, and can be irradiated with active energy rays to reduce the adhesive strength when peeling is required. Examples of the active energy rays include gamma rays, ultraviolet rays, visible rays, infrared rays (hot rays), radio frequency waves, alpha rays, beta rays, electron beams, plasma streams, ionizing rays, and particle beams. In addition, in this specification, only the case of "adhesive layer" refers to the adhesive layer before the adhesive is hardened and the adhesive force decreases.

As the resin material constituting the active energy ray-curable adhesive, for example, an ultraviolet curing system (Kato Kiyosuke, issued by the Comprehensive Technology Center, (1989)), light curing technology (Technical Information Association (2000)), Japan The resin materials described in Japanese Patent Laid-Open No. 2003-292916, Japanese Patent No. 4151850, etc. More specifically, a resin material (R1) containing a polymer and a reactive energy ray reactive compound (monomer or oligomer) as a parent agent, and a resin material (R2) containing an active energy ray reactive polymer Wait.

Examples of the polymer used as the masterbatch include natural rubber, polyisobutylene rubber, styrene-butadiene rubber, styrene-isoprene-styrene block copolymer rubber, recycled rubber, and butyl rubber. , Polyisobutylene rubber, nitrile rubber (NBR) and other rubber-based polymers; polysiloxane-based polymers; acrylic polymers, etc. These polymers can be used alone or in combination of two or more. From the viewpoint of affinity with the sealing material, the polymer used as a masterbatch is preferably a base polymer that can be preferably used as the acrylic adhesive, rubber adhesive, or polysiloxane adhesive. Illustrated polymer.

Examples of the active energy ray-reactive compound include photoreactive monomers having a functional group having a carbon-carbon multiple bond such as acryl, methacryl, vinyl, allyl, and ethynyl, or Oligomer. Specific examples of the photoreactive monomer or oligomer include trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, and pentaerythritol tri(methyl). ) Acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth) Acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, etc. contain (meth) Acryloyl compound; the second to pentamer of (meth)acryloyl compound.

In addition, as the active energy ray-reactive compound, monomers such as epoxidized butadiene, glycidyl methacrylate, acrylamide, and vinyl siloxane; or oligomers composed of the monomers can also be used . The resin material (R1) containing these compounds can be hardened by high energy rays such as ultraviolet rays and electron beams.

Furthermore, as the active energy ray-reactive compound, a mixture of organic salts such as onium salts and compounds having a plurality of heterocycles in the molecule can also be used. The mixture can be irradiated with active energy rays (for example, ultraviolet rays, electron beams) to crack organic salts to generate ions, and use this as a starting species to cause a ring-opening reaction of a heterocycle to obtain a three-dimensional network structure. Examples of the organic salts include, for example, iodonium salts, phosphonium salts, antimony salts, osmium salts, and borate salts. Examples of the heterocycle in the compound having a plurality of heterocycles in the molecule include ethylene oxide, oxetane, oxolane, ethylene sulfide, and aziridine.

In the above-mentioned resin material (R1) containing the polymer and the active energy ray-reactive compound as the mother agent, the content ratio of the active energy ray reactive compound is preferably 0.1 part by weight with respect to 100 parts by weight of the polymer as the mother agent Parts to 500 parts by weight, more preferably 1 part to 300 parts by weight, and further preferably 10 parts to 200 parts by weight. Within such a range, an adhesive layer with low affinity with the sealing material can be formed.

The above-mentioned resin material (R1) containing a polymer as a mother agent and an active energy ray-reactive compound may contain any appropriate additives as necessary. Examples of the additives include active energy ray polymerization initiators, active energy ray polymerization accelerators, crosslinking agents, plasticizers, and vulcanizing agents. As the active energy ray polymerization initiator, any appropriate initiator can be used according to the type of active energy ray used. The active energy ray polymerization initiator may be used alone or in combination of two or more. In a resin material (R1) containing a polymer as a parent agent and an active energy ray reactive compound, the active energy ray is polymerized The content ratio of the initiator is preferably 0.1 parts by weight to 10 parts by weight, and more preferably 1 part by weight to 5 parts by weight with respect to 100 parts by weight of the polymer used as the mother agent.

Examples of the active energy ray-reactive polymer include polymers having a functional group having a carbon-carbon multiple bond such as acryl, methacryl, vinyl, allyl, and ethynyl. Specific examples of the polymer having an active energy ray-reactive functional group include polymers composed of polyfunctional (meth)acrylates. The polymer composed of multifunctional (meth)acrylate preferably has an alkyl ester having a carbon number of 4 or more, more preferably has an alkyl ester having a carbon number of 6 or more, and further preferably has a carbon number of For alkyl esters of 8 or more, alkyl esters having 8 to 20 carbon atoms are particularly preferred, and alkyl esters having 8 to 18 carbon atoms are most preferred. If a polymer having a long side chain is used, an adhesive layer with low affinity with the sealing material can be formed. In the polymer, the content ratio of the structural unit having an alkyl ester having a carbon number of 4 or more relative to the total structural unit constituting the polymer is preferably 30% by weight or more, and more preferably 50% by weight or more Furthermore, it is preferably 70% by weight to 100% by weight, and particularly preferably 80% by weight to 100% by weight. Within such a range, an adhesive layer with low affinity with the 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 active energy ray-reactive polymer may contain any appropriate additives as necessary. Specific examples of the additives are the same as the additives that can be contained in the resin material (R1) containing the polymer and the active energy ray-reactive compound as the mother agent. In the resin material (R2) containing an active energy ray reactive polymer, the content ratio of the active energy ray polymerization initiator is preferably 0.1 to 10 parts by weight relative to 100 parts by weight of the active energy ray reactive polymer , It is more preferably 1 part by weight to 5 parts by weight.

<heat-expandable microspheres>

In one embodiment, the adhesive layer further includes thermally expandable microspheres. An adhesive sheet having an adhesive layer containing thermally expandable microspheres is heated to make the thermally expandable microspheres Expansion or foaming creates unevenness on the adhesive surface, as a result, the adhesive force decreases or disappears. Such an adhesive sheet can be easily peeled off by heating.

As the heat-expandable microspheres, as long as they are expandable or foamable by heating, any appropriate heat-expandable microspheres can be used. As the heat-expandable microspheres, for example, microspheres formed by encapsulating a substance that easily expands by heating in an elastic shell can be used. Such thermally expandable microspheres can be produced by any suitable method, such as coacervation, interfacial polymerization method, and the like.

Examples of substances that easily expand by heating include propane, propylene, butene, n-butane, isobutane, isopentane, neopentane, n-pentane, n-hexane, isohexane, heptane , Octane, petroleum ether, methane halide, tetraalkyl silane and other low-boiling liquids; azodicarboxylamide vaporized by thermal decomposition and so on.

Examples of the substance constituting the shell include polymers composed of nitrile monomers such as acrylonitrile, methacrylonitrile, α -chloroacrylonitrile, α -ethoxyacrylonitrile, and fumaronitrile; Acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid and other carboxylic acid monomers; vinylidene chloride; vinyl acetate; methyl (meth)acrylate, (meth Group) ethyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, iso (meth) acrylate (Meth)acrylates such as esters, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, β -carboxyethyl acrylate; styrene, α -methylstyrene, chlorostyrene and other styrene monomers Body; acrylamide, substituted acrylamide, methacrylamide, substituted methacrylamide and other amide monomers. The polymer composed of these monomers may be a homopolymer or a copolymer. Examples of the copolymer include vinylidene chloride-methyl methacrylate-acrylonitrile copolymer, methyl methacrylate-acrylonitrile-methacrylonitrile copolymer, and methyl methacrylate-acrylonitrile copolymerization. , Acrylonitrile-methacrylonitrile-itaconic acid copolymer, etc.

As the thermally expandable microspheres, an inorganic foaming agent or an organic foaming agent can also be used. Examples of the inorganic foaming agent include ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, ammonium nitrite, sodium borohydride, and various azides. In addition, examples of the organic foaming agent include chlorofluorinated alkane-based compounds such as trichloromonofluoromethane and dichloromonofluoromethane; azobisisobutyronitrile, azodicarboxyamide, and azodicarboxy Azo compounds such as barium acid; p-toluenesulfonyl hydrazide, diphenylbenzene-3,3'-disulfonyl hydrazide, 4,4'-oxybis(benzenesulfonyl hydrazide), allyl bis(sulfonyl hydrazide) Hydrazines) and other hydrazine compounds; p-toluenesulfonylamidourea, 4,4'-oxybis(benzenesulfonylamidourea) and other aminourea compounds; 5- Triazolyl-1,2,3,4-thitriazole and other triazole compounds; N,N'-dinitrosopentamethylenetetramine, N,N'-dimethyl-N,N'- N-nitroso compounds such as dinitroso-p-xylylenediamide, etc.

Commercially available products can also be used for the thermally expandable microspheres. Specific examples of commercially available thermally expandable microspheres include the brand name "Matsumoto Microsphere" (grades: F-30, F-30D, F-36D, F-36LV, F-50) manufactured by Matsumoto Oil & Pharmaceutical Co., Ltd. , F-50D, F-65, F-65D, FN-100SS, FN-100SSD, FN-180SS, FN-180SSD, F-190D, F-260D, F-2800D), trade names made by Japan Fillite EXPANCEL" (levels: 053-40, 031-40, 920-40, 909-80, 930-120), "DAIFOAM" (levels: H750, H850, H1100, S2320D, S2640D, M330) manufactured by Wu Yu Chemical Industry Co., Ltd. , M430, M520), "ADVANCELL" (levels: EML101, EMH204, EHM301, EHM302, EHM303, EM304, EHM401, EM403, EM501) manufactured by Sekisui Chemical Industry Corporation.

The particle diameter of the thermally expandable 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, and particularly preferably 10 μm to 15 μm. Therefore, when the particle size of the thermally expandable microspheres before heating is referred to as the average particle size, it is preferably 6 μm to 45 μm, and more preferably 15 μm to 35 μm. The above-mentioned particle size and average particle size are values obtained by the particle size distribution measurement method in the laser scattering method.

The above-mentioned thermally expandable microspheres preferably have an appropriate strength that does not break before the volume expansion ratio is 5 times or more, more preferably 7 times or more, and further preferably 10 times or more. When using such thermally expandable microspheres, heat treatment can be used And make the adhesion drop efficiently.

The content ratio of the heat-expandable microspheres in the above-mentioned adhesive layer can be appropriately set according to a desired decrease in adhesive force and the like. The content ratio of the heat-expandable 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 adhesive layer. 100 parts by weight.

When the adhesive layer contains thermally expandable microspheres, the arithmetic surface roughness Ra of the adhesive layer before expansion of the thermally expandable microspheres (that is, before heating) is preferably 500 nm or less, more preferably 400 nm or less, and It is preferably 300 nm or less. Within this range, an adhesive sheet excellent in adhesion to the adherend can be obtained. Such an adhesive layer having excellent surface smoothness can be obtained by, for example, setting the thickness of the adhesive layer to the above range, and applying and transferring the adhesive layer to the separator when other adhesive layers are provided. . Furthermore, as described in the above item A, when the adhesive sheet of the present invention further includes another adhesive layer, the other adhesive layer may also include thermally expandable microspheres. In the case where the other adhesive layer includes thermally expandable microspheres, the arithmetic surface roughness Ra of the adhesive layer is preferably within the above range.

When the adhesive layer contains heat-expandable microspheres, the adhesive layer preferably includes a basic polymerization whose dynamic storage elastic modulus at 80°C is in the range of 5 kPa to 1 MPa (more preferably 10 kPa to 0.8 MPa) Adhesive composed of materials. If it is such an adhesive layer, it can form an adhesive sheet which has appropriate adhesiveness before heating and whose adhesive force is easily lowered by heating. Furthermore, the dynamic storage elastic modulus can be measured using a dynamic viscoelasticity measuring device (for example, the trade name "ARES" manufactured by Rheometrics) under the measurement conditions of a frequency of 1 Hz and a heating rate of 10°C/min.

C. Base layer

In one embodiment, the adhesive sheet of the present invention includes an adhesive layer and a substrate layer. Fig. 2(a) is a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention. The adhesive sheet 100 includes an adhesive layer 10 and a substrate layer 30 disposed on one side of the adhesive layer 10. Figure 2(b) It is a schematic cross-sectional view of an adhesive sheet according to another embodiment of the present invention. The adhesive sheet 200 includes an adhesive layer 10 and a substrate layer 30, and the adhesive layer 10 is disposed on both sides of the substrate layer 30. The two-layer adhesive layer can be an adhesive layer of the same composition or an adhesive layer of different composition. Furthermore, the adhesive layer may be provided on one side of the base material layer, and another adhesive layer may be provided on the other side.

In the case where the adhesive sheet of the present invention has a base material layer, the holding force between the base material layer and the adhesive layer is preferably 6.0 N/19 mm or more, and more preferably 15 N/19 mm or more.

The above-mentioned gripping force can be measured as follows. The above-mentioned gripping force can be obtained as follows: (i) on the side of the adhesive sheet with a width of 20 mm×length 150 mm opposite to the adhesive layer (for example, in the case of an adhesive sheet composed of a base material layer/adhesive layer) When it is the outer surface of the base material layer) the SUS board is attached to the entire surface through a specific double-sided adhesive tape; (ii) the outer surface of the adhesive layer of the adhesive sheet is attached with a size of 19 mm in width × 150 mm in length and Sheets for evaluating the adhesiveness including polyester resins (sheets with a peel adhesion of 10N/20mm~20N/20mm to polyethylene terephthalate, such as the trade name "No.315" manufactured by Nitto Denko Corporation Tape”) on the adhesive surface, prepare samples for evaluation; (iii) Measure the peeling force between the base material layer and the adhesive layer of the adhesive sheet by tensile test. Furthermore, the above (i) to (iii) are performed at an ambient temperature of 23°C. The conditions of the tensile test when measuring the peeling force: the peeling speed is 50 mm/min and the peeling angle is 180°.

As described above, an adhesive sheet with high gripping force between the base material layer and the adhesive layer is an adhesive sheet that is not likely to cause paste residues. If such an adhesive sheet, the effect of the present invention becomes remarkable. In the case of evaluation by the above method, it is more preferable that the interface between the base material layer and the adhesive layer does not peel, for example, an adhesive sheet that is peeled between the SUS plate and the base material layer. An adhesive sheet with high gripping force can be obtained by, for example, using the rubber-based adhesive (Rub1) as an adhesive and adding an isocyanate-based crosslinking agent to the adhesive.

Examples of the base material layer include resin sheets, nonwoven fabrics, paper, metal foils, woven fabrics, rubber sheets, foamed sheets, and laminates of these (particularly including resin sheets Wood laminate) etc. Examples of the resin constituting the resin sheet include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polyethylene ( PE), polypropylene (PP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), polyamide (nylon), wholly aromatic polyamide (aromatic polyamide), polyacetal Amine (PI), polyvinyl chloride (PVC), polyphenylene sulfide (PPS), fluorine resin, polyether ether ketone (PEEK), etc. Examples of the nonwoven fabric include nonwoven fabrics including manila hemp and other nonwoven fabrics made of heat-resistant natural fibers; synthetic resin nonwoven fabrics such as polypropylene resin nonwoven fabrics, polyethylene resin nonwoven fabrics, and ester resin nonwoven fabrics. Examples of the metal foil include copper foil, stainless steel foil, and aluminum foil. Examples of paper include Japanese paper and kraft paper.

The thickness of the above-mentioned base material layer can be set to any appropriate thickness according to desired strength, flexibility, use purpose, and the like. The thickness of the substrate 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, and most preferably 5 μm to 250 μm.

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

Examples of the organic coating material include those described in Plastic Hard Coating Material II (CMC Publishing, (2004)). Preferably, a urethane-based polymer is used, more preferably a polyacrylate urethane, a polyester urethane, or a precursor thereof. The reason is that the coating to the substrate. It is easy to apply, and can choose a variety of substances industrially, and it can be obtained inexpensively. The urethane-based polymer is, for example, a polymer formed from a reaction mixture of an isocyanate 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 also contain chain extenders such as polyamines, anti-aging agents, oxidation stabilizers, etc. as optional additives. The thickness of the organic coating layer is not particularly limited. For example, it is preferably about 0.1 μm to 10 μm, preferably about 0.1 μm to 5 μm, and more preferably about 0.5 μm to 5 μm.

D. Elastic layer

The adhesive sheet of the present invention may further have 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 is preferably disposed when the adhesive layer 10 includes the above-mentioned thermally expandable microspheres. In addition, when the adhesive sheet 300 includes the base material layer 30, the elastic layer 40 may be disposed between the adhesive layer 10 and the base material layer 30 as shown in the example, or may be disposed between the base material layer and the adhesive The opposite side of the layer. The elastic layer 40 may be provided with two or more layers. In addition, FIG. 3 shows an example in which one elastic layer 40 is provided and the elastic layer 40 is disposed between the adhesive layer 10 and the base material layer 30. The provision of the elastic layer 40 improves the adherence to the adherend. In addition, when the adhesive sheet provided with the elastic layer 40 is heated at the time of peeling, deformation (expansion) in the surface direction of the adhesive layer is restricted, and deformation in the thickness direction takes priority. As a result, the releasability is improved.

The elastic layer contains a base polymer, and as the base polymer, a polymer exemplified as the base polymer constituting the adhesive layer can be used. In addition, the elastic layer may include natural rubber, synthetic rubber, synthetic resin, and the like. Examples of the synthetic rubber and synthetic resin include: nitrile-based, diene-based, acrylic-based synthetic rubber; polyolefin-based, polyester-based thermoplastic elastomers; ethylene-vinyl acetate copolymer; polyurethane ; Polybutadiene; Soft PVC, etc. The base polymer constituting the elastic layer may be the same as or different from the base polymer forming the adhesive layer. The elastic layer may be a foamed film formed of the base polymer. The foamed film can be obtained by any appropriate method. Furthermore, the elastic layer and the adhesive layer can be distinguished by the difference of the base polymer and/or the presence or absence of heat-expandable microspheres (the elastic layer does not contain heat-expandable microspheres).

The elastic layer may contain any appropriate additives as needed. Examples of such additives include crosslinking agents, vulcanizing agents, adhesion-imparting agents, plasticizers, softeners, fillers, and anti-aging agents. When a hard resin such as polyvinyl chloride is used as the base polymer, it is preferable to use a plasticizer and/or a softener in combination 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. Within such a range, the elastic layer can sufficiently exhibit the above function.

The tensile elastic modulus of the elastic layer at 25°C is preferably less than 100 MPa, more preferably 0.1 MPa to 50 MPa, and still more preferably 0.1 MPa to 10 MPa. Within such a range, the elastic layer can sufficiently exhibit the above function.

E. Spacer

The adhesive sheet of the present invention may be further provided with a separator as needed. At least one surface of the separator becomes a peeling surface and can be provided to protect the adhesive layer. The separator can be composed of any suitable material.

F. Manufacturing method of adhesive sheet

The adhesive sheet of the present invention can be manufactured by any appropriate method. Regarding the adhesive sheet of the present invention, for example, a method of directly applying a composition containing an adhesive on a substrate layer (any suitable substrate in the case of obtaining an adhesive sheet without a substrate layer), Or a method for transferring a coating layer formed by applying a composition containing an adhesive on any suitable substrate to the substrate layer, etc. The composition containing the adhesive may contain any suitable solvent.

In the case of forming an adhesive layer containing heat-expandable microspheres, a composition containing heat-expandable microspheres, an adhesive, and any appropriate solvent may be applied to the substrate layer to form the adhesive layer. Alternatively, after spreading the heat-expandable microspheres on the adhesive coating layer, the heat-expandable microspheres are buried in the adhesive using a laminator or the like to form an adhesive layer containing the heat-expandable microspheres.

When the adhesive layer has the above-mentioned elastic layer, the elastic layer can be formed, for example, by coating a composition for forming an elastic layer on the substrate layer or the adhesive layer.

As the coating method of the above-mentioned adhesive and each composition, any appropriate coating method can be adopted. For example, each layer can be formed by drying after coating. Examples of the coating method include the use of a multi-coater, die coater, and gravure coating. Coating methods for machines, applicators, etc. Examples of the drying method include natural drying and heat drying. The heating temperature during heating and drying can be set to any appropriate temperature according to the characteristics of the substance to be dried.

[Example]

Hereinafter, the present invention will be specifically described by examples, but the present invention is not limited by these examples. The evaluation methods in the examples are as follows. In the examples, unless otherwise noted, "parts" and "%" are based on weight.

(1) Contact angle

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

2 μl of 4-tert-butylphenyl glycidyl ether was added dropwise on the surface of the adhesive layer, and the contact angle (N=5) after 5 seconds was measured. The contact angle was measured using a contact angle meter (manufactured by Kyowa Interface Co., Ltd., trade name "CX-A type") under an atmosphere of 23°C and 50% RH.

(2) sp value

The sp value of the polymer in the adhesive layer after the formation of the adhesive sheet is based on the method of Fedors (Yumoto Yamamoto, "Sp Value Basics. Application and Calculation Method", published by Information Organization Co., Ltd., April 3, 2006 Issue, pages 66 to 67). Specifically, the sp value is determined by the evaporation energy Δe(cal) at 25°C of each atom or atomic group forming the polymer, and the molar volume ΔV(25) at 25°C of each atom or atomic group forming the polymer cm ³ ), calculated according to the following formula.

Sp value = (Σ△e/Σ△V) ^1/2

In addition, when the polymer is a copolymer, the Sp value is calculated as follows: calculate the Sp value of each homopolymer of each structural unit constituting the copolymer, and multiply the Sp values by each The molar fraction of the structural unit is summed up.

In the above case, regarding the analysis method of each structural unit (analysis of the composition of the polymer), only the adhesive layer can be appropriately taken from the adhesive sheet, and the immersion in dimethyl Soluble fractions obtained from organic solvents such as methylamide (DMF), acetone, methanol, and tetrahydrofuran (THF) are recovered by gel filtration permeation chromatography (GPC), nuclear magnetic resonance spectroscopy (NMR), infrared Obtained by the analytical methods of spectrometry (IR) and quality analysis.

(3) Adhesion

On the entire surface of the adhesive sheet (width 20mm × length 140mm) opposite to the adhesive layer, use a double-sided adhesive tape (manufactured by Nitto Denko Corporation, trade name "No. 531") using a 2kg hand roller With SUS304 board.

Then, a polyethylene terephthalate film (manufactured by Toray Industries, trade name "Lumirror S-10", thickness: 25 μm, width: 30 mm) (temperature: 23°C, Humidity: 65%, 2kg roller round trip once).

The sample for evaluation obtained in the above manner was used in a tensile test. As the tensile testing machine, the trade name "Shimadzu Autograph AG-120kN" manufactured by Shimadzu Corporation was used. After setting the evaluation sample in the tensile testing machine, it was left at an ambient temperature of 23° C. for 30 minutes, and then the tensile test was started. The conditions of the tensile test were set to a peeling angle: 180°, and a peeling speed (tensile speed): 300 mm/min. The load when peeling the adhesive sheet from the above PET film was measured, and the maximum load at this time was taken as the adhesive force of the adhesive sheet.

(4) Holding power

On the entire surface of the adhesive sheet (width 20 mm × length 140 mm) opposite to the adhesive layer, through a double-sided adhesive tape (manufactured by Nitto Denko Corporation, trade name "No. 531"), use 2 kg hand pressure The roller is attached to a SUS304 plate (width 40mm × length 120mm).

Then, a sheet for evaluation of bonding (manufactured by Nitto Denko Corporation, trade name "No. 315 Tape", width 19 mm × length 150 mm) (temperature: 23° C., humidity: 65%, 2 kg roller round trip).

The sample for evaluation obtained in the above manner was used in a tensile test. As the tensile testing machine, the trade name "Shimadzu Autograph AG-" manufactured by Shimadzu Corporation was used. 120kN". The conditions of the tensile test were set to a peeling angle: 180°, and a peeling speed (tensile speed): 50 mm/min. Holding the above evaluation sheet, measure the load when peeling the adhesive layer from the substrate layer of the adhesive sheet, and use the maximum load at this time as the gripping force of the substrate layer and the adhesive layer.

(5) Adhesion value

On the entire surface of the adhesive sheet (width 20 mm × length 50 mm) opposite to the adhesive layer, through a double-sided adhesive tape (manufactured by Nitto Denko Corporation, trade name "No. 531"), use 2 kg hand pressure The roller was attached to a slide glass (made by Songlang Glass Industry Co., Ltd., 26 mm × 76 mm).

Using a probe viscosity measuring machine (manufactured by RHESCA, trade name "TACKINESS Model TAC-II"), the probe viscosity value of the outer surface of the adhesive layer in the evaluation sample obtained in the above manner was measured. The measurement conditions are: probe processing speed (Immersion speed): 30 mm/min, test speed (test speed): 30 mm/min, tight load (Prelod): 100 gf, tight hold time (press time): 1 second, probe Area (Probe Area): 5mm SUS.

(6) Retention test

At an ambient temperature of 23°C, use a 2kg hand pressure roller to attach the entire surface of the adhesive layer of the adhesive sheet (width 10mm × length 150mm) to the entire surface of the bakelite board (manufactured by Futamura Chemical Corporation, trade name "TAIKOLITE FL-102" ", width 25mm × length 125mm × thickness 2mm) the central part.

For the evaluation sample obtained in the above manner, it was left to stand at 40° C. for 30 minutes for curing, and then used a tape creep tester (manufactured by Imada Manufacturing Co., Ltd., type/model "12-unit weight/041") , Apply a load of 1.96N, and leave it in this state for 2 hours.

Using the position before pressing on the bakelite as a reference, the moving distance (offset) of the adhesive sheet due to pressing is measured. The shorter the moving distance, the higher the holding force.

(7) Surface roughness

The arithmetic surface roughness Ra of the surface of the adhesive layer of the adhesive sheet is measured in accordance with JIS B0601. As the measuring machine, an optical surface roughness meter (manufactured by Veeco Metrogy Group, trade name "Wyko NT9100") was used.

(8) Gap height suppression effect

100 parts by weight of naphthalene type bifunctional epoxy resin (manufactured by DIC Corporation, trade name "HP4032D", epoxy equivalent: 144), 40 parts by weight of phenoxy resin (manufactured by Mitsui Chemicals Co., Ltd., trade name "EP4250"), phenol-based Resin (made by Meiwa Chemical Co., Ltd., trade name "MEH-8000") 129 parts by weight, spherical silica (made by Admatechs, trade name "SO-25R") 1137 parts by weight, dye (made by Orient Chemical Industries, Inc., product 14 parts by weight of the name "OIL BLACK BS", 1 part by weight of the curing catalyst (manufactured by Shikoku Chemical Co., Ltd., trade name "2PHZ-PW"), and 30 parts by weight of methyl ethyl ketone are mixed to prepare a resin solution A ( Solid content concentration: 23.6% by weight).

A Si wafer (1 cm×1 cm, thickness 500 μm) is placed on the adhesive layer of the adhesive sheet, and the resin solution A is coated on the adhesive layer to cover and seal the Si wafer (coating size: 3cm×3cm), the resin solution is heated at 170°C for 10 minutes to harden it, and a structure including Si wafers and sealing resin is formed on the adhesive layer of the adhesive sheet.

After cooling, the adhesive sheet is peeled from the structure. For the peeled adhesive sheet, the difference between the thickness of the adhesive layer in the portion not in contact with the Si wafer and the thickness of the adhesive layer in the portion in contact with the Si wafer is used as the gap height.

(9) Paste residue

As in (8) above, a structure including a Si wafer and a sealing resin is formed on the adhesive sheet, and after cooling, the adhesive sheet is peeled from the structure. After peeling, the bonding surface of the above-mentioned structure was observed with a microscope (manufactured by KEYENCE, trade name "VHX-100", magnification: 150 times) to confirm the presence or absence of the adhesive layer component attached to the structure. in FIG. 1, The case where there are not more than 5 attachments with a particle size of 100 μm (in the case of indefinite shape, the length of the longest side is 100 μm) is denoted as ○, and the case where there are 5 or more are marked as ×.

[Example 1]

The acrylic copolymer as the base polymer (copolymer of 2-ethylhexyl acrylate and hydroxyethyl acrylate, and 2-ethylhexyl acrylate structural unit: hydroxyethyl acrylate structural unit = 100: 5 (weight Ratio)) 100 parts by weight, isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "CORONATE L") 1.5 parts by weight, terpene phenol-based adhesion-imparting resin (made by YASAHARA CHEMICAL Co., Ltd., trade name "YS POLYSTAR S145" ) 10 parts by weight and 100 parts by weight of toluene are mixed to prepare a composition for forming an adhesive layer.

This composition for forming an adhesive layer was coated on one side of a polytetrafluoroethylene film (made by Toray Co., Ltd., trade name "Lumirror S10", thickness 38 μm) as a base layer to obtain a base layer and adhesion Adhesive sheet composed of an agent layer (thickness 10 μm).

[Example 2]

Acrylic copolymer as a base polymer (copolymer of 2-ethylhexyl acrylate and acrylic acid and trimethylolpropane acrylate, and 2-ethylhexyl acrylate structural unit: acrylic structural unit: trimethylol Propane acrylate structural unit = 100: 3: 0.03 (weight ratio)) 100 parts by weight, epoxy-based crosslinking agent (Mitsubishi Gas Chemical Co., Ltd., trade name "TETRAD-C") 0.5 parts by weight, terpene phenol series 10 parts by weight of an adhesion-imparting resin (manufactured by YASUHARA CHEMICAL, trade name "YS POLYSTAR S145") and 100 parts by weight of toluene were mixed to prepare a composition for forming an adhesive layer.

This composition for forming an adhesive layer was coated on one side of a polytetrafluoroethylene film (made by Toray Co., Ltd., trade name "Lumirror S10", thickness 38 μm) as a base layer to obtain a base layer and adhesion Adhesive sheet composed of an agent layer (thickness 10 μm).

[Example 3]

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

This adhesive layer forming composition was coated on one side of a polyimide film (manufactured by Toray Dupont, trade name "KAPTON 200H", thickness 50 μm) as a base layer to obtain a base layer and An adhesive sheet composed of an adhesive layer (10 μm).

[Example 4]

100 parts by weight of polyisobutylene rubber (manufactured by BASF JAPAN, trade name "Oppanol B80"), 1.5 parts by weight of polyolefin containing hydroxyl group (manufactured by Idemitsu Kosei Co., Ltd., trade name "EPOL"), isocyanate-based crosslinking agent ( Nippon Polyurethane Industry 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.

This composition for forming an adhesive layer was coated on one side of a polytetrafluoroethylene film (made by Toray Co., Ltd., trade name "Lumirror S10", thickness 38 μm) as a base layer to obtain a base layer and adhesion Adhesive sheet composed of an agent layer (thickness 10 μm).

[Example 5]

To the composition for forming an adhesive layer, further 30 parts by weight of heat-expandable microspheres (manufactured by Matsumoto Oil and Pharmaceutical Co., Ltd., trade name "Matsumoto Microsphere F-50") were added, and the thickness of the adhesive layer was set to 40 μm, except for In the same manner as in Example 1, an adhesive sheet was obtained.

[Example 6]

To the composition for forming an adhesive layer, further 30 parts by weight of heat-expandable microspheres (manufactured by Matsumoto Oil and Pharmaceutical Co., Ltd., trade name "Matsumoto Microsphere F-50") were added, and the thickness of the adhesive layer was set to 40 μm, except for In the same manner as in Example 2, an adhesive sheet was obtained.

[Example 7]

To the composition for forming an adhesive layer, further 30 parts by weight of heat-expandable microspheres (manufactured by Matsumoto Oil and Pharmaceutical Co., Ltd., trade name "Matsumoto Microsphere F-50") were added, and the thickness of the adhesive layer was set to 40 μm, except for In the same manner as in Example 3, an adhesive sheet was obtained.

[Example 8]

To the composition for forming an adhesive layer, further 30 parts by weight of heat-expandable microspheres (manufactured by Matsumoto Oil and Pharmaceutical Co., Ltd., trade name "Matsumoto Microsphere F-50") were added, and the thickness of the adhesive layer was set to 40 μm, except for In the same manner as in Example 4, an adhesive sheet was obtained.

[Example 9]

In the same manner as in Example 1, a composition for forming an adhesive layer was prepared.

The acrylic copolymer (copolymer of ethyl acrylate and 2-ethylhexyl acrylate and hydroxyethyl acrylate, and 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 isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Industry, trade name "CORONATE L"), and 100 parts by weight of toluene are mixed to prepare an elastic layer Forming composition.

The acrylic copolymer (copolymer of ethyl acrylate and 2-ethylhexyl acrylate and hydroxyethyl acrylate, and 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 isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Industry, trade name "CORONATE L"), rosin phenol-based adhesion-imparting resin (manufactured by Sumitomo Bakelite) , Trade name "Sumilite Resin PR-12603") 15 parts by weight, heat-expandable microspheres (manufactured by Matsumoto Oil & Drug Co., Ltd., trade name "Matsumoto Microsphere F-50") 35 parts by weight, and 100 parts by weight of toluene are mixed to prepare other The composition for forming an adhesive layer.

The above adhesive layer-forming composition was applied to one side of a PET film (made by Toray Industries, trade name "Lumirror S10", thickness 38 μm) as a base layer, and an adhesive layer was formed on the base layer ( Thickness 10μm). Furthermore, an elastic layer forming composition was coated on the other surface of the PET film, and an elastic layer (thickness 10 μm) was formed on the base layer.

In addition, the other adhesive layer forming composition was coated on another PET film to form another adhesive layer (thickness 35 μm). The other adhesive layer is transferred onto the above-mentioned elastic layer to obtain an adhesive sheet composed of an adhesive layer/base material layer/elastic layer/other adhesive layer.

[Example 10]

An adhesive sheet was obtained in the same manner as in Example 9 except that the composition for forming an adhesive layer obtained in Example 2 was used as the composition for forming an adhesive layer.

[Example 11]

An adhesive sheet was obtained in the same manner as in Example 9 except that the composition for forming an adhesive layer obtained in Example 3 was used as the composition for forming an adhesive layer.

[Example 12]

An adhesive sheet was obtained in the same manner as in Example 9 except that the composition for forming an adhesive layer obtained in Example 4 was used as the composition for forming an adhesive layer.

[Comparative Example 1]

The acrylic copolymer (copolymer of methyl acrylate and 2-ethylhexyl acrylate and acrylic acid, and methyl acrylate structural unit: 2-ethylhexyl acrylate structural unit: acrylic structural unit = 15: 85: 8 ( Weight ratio)) 100 parts by weight, epoxy-based crosslinking agent (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name "TETRAD-C") 3 parts by weight, terpenephenol-based adhesion-imparting resin (manufactured by Yasuhara Chemical Co., Ltd., trade name "YS" POLYSTAR S145") 10 parts by weight and 100 parts by weight of toluene are mixed to prepare a composition for forming an adhesive layer.

The composition for forming an adhesive layer is applied to a polytetrafluoroethylene film as a substrate layer A single-sided (manufactured by Toray Corporation, trade name "Lumirror S10", thickness 38 μm) was used to obtain an adhesive sheet composed of a base material layer and an adhesive layer (thickness 10 μm).

It can be seen from Table 1 that the adhesive sheet of the present invention has an adhesive layer having a contact angle of 15° or more with respect to 4-tert-butylphenyl glycidyl ether, that is, has an adhesive with low affinity to the sealing resin The adhesive layer can obtain an adhesive sheet with less gap height and less paste residue.

Claims (8)

An adhesive sheet for temporarily fixing materials when a plurality of semiconductor wafers are sealed in batches by a sealing resin, which is an adhesive sheet with an adhesive layer, and the adhesive layer includes an acrylic adhesive, the acrylic The adhesive contains an acrylic polymer having an alkyl ester having a carbon number of 6 or more in the side chain as a base polymer. In the acrylic polymer, relative to the total structural unit constituting the acrylic polymer, The content ratio of the structural unit having an alkyl ester having a carbon number of 6 or more in the chain is 50% by weight or more, and the contact angle of the surface of the adhesive layer with respect to 4-third butylphenyl glycidyl ether is 15° or more, The adhesive strength of the adhesive sheet to polyethylene terephthalate at 23°C is more than 0.5N/20mm. An adhesive sheet for temporarily fixing a material when sealing a plurality of semiconductor wafers in batches with a sealing resin as claimed in item 1, wherein the sp value of the material constituting the adhesive in the above adhesive layer is 7 (cal/cm ³ ) ^1/2 ~10(cal/cm ³ ) ^1/2 . Adhesive sheet for temporarily fixing materials when sealing a plurality of semiconductor chips in batches by sealing resin as in claim 1 or 2, wherein the probe viscosity value of the above adhesive layer is 50N/5mm

the above. An adhesive sheet for temporarily fixing a material when a plurality of semiconductor wafers are sealed in batches by a sealing resin as described in claim 1 or 2, wherein the adhesive layer further includes thermally expandable microspheres. An adhesive sheet for temporarily fixing a material when a plurality of semiconductor wafers are sealed in batches with a sealing resin as described in claim 4, wherein the arithmetic surface roughness Ra of the adhesive layer before heating the thermally expandable microspheres is Below 500nm. Adhesive sheet for temporarily fixing materials when sealing a plurality of semiconductor wafers in batches by sealing resin as described in claim 1 or 2, wherein the outer surface of the above-mentioned adhesive layer is applied over the entire surface at an ambient temperature of 23°C Put it on the bakelite board, and cure for 30 minutes at an ambient temperature of 40°C, then apply a load of 1.96N and keep it for 2 hours. At this time, the deviation from the bakelite board is 0.5mm or less. The adhesive sheet for temporarily fixing the material when the plurality of semiconductor wafers are sealed in batches by the sealing resin as in claim 1 or 2, which further has a substrate layer, which is arranged on one side or both sides of the substrate layer There is the above adhesive layer. An adhesive sheet for temporarily fixing a material when a plurality of semiconductor wafers are sealed in batches by a sealing resin as claimed in claim 7, wherein the holding force of the base material layer and the adhesive layer is 6.0 N/19 mm or more.