JP6448333B2 - Adhesive sheet - Google Patents

Description

  The present invention relates to an adhesive sheet.

  In recent years, there has been a demand for miniaturization and precision of electronic components, and ceramic capacitors are also of the so-called “0603 size” (0.6 mm × 0.3 mm) and “0402 size” (0.4 mm × 0.2 mm). As represented by the appearance, miniaturization is progressing. In addition, parts such as ceramic capacitors are also required to have a high capacity, and accordingly, it is required to accurately manufacture highly multilayer ceramic capacitors that greatly exceed several hundred layers.

  As an example of the method for producing the ceramic capacitor, (1) a printing process for printing an electrode on a ceramic pre-fired sheet (hereinafter also referred to as a green sheet), (2) a green sheet on which an electrode is formed is formed in a predetermined layer (for example, 150 layers) Laminating step for laminating, (3) Pressurizing step for press-pressing the laminated body obtained in (2), (4) Pressurized laminated body having a predetermined size (for example, 0.4 mm × 0) 2 mm), and a cutting process for cutting and separating to obtain a chip, and (5) a firing process for firing the obtained chip. In (2) above, when pressure treatment is performed during the lamination process, that is, when an intermediate formed by stacking one layer (or several layers) is pressed each time it is stacked. There is also.

  In the manufacturing method, the printing step to the cutting step can be performed on the pressure-sensitive adhesive sheet to temporarily fix the workpiece. The pressure-sensitive adhesive tape used in this way has an adhesive force that exhibits sufficient fixability in the printing step to the cutting step, and has a low adhesive strength that can be easily peeled off from the chip after the cutting step or after the firing step. It is preferable that

  As the above-mentioned pressure-sensitive adhesive sheet, a low-pressure-sensitive pressure-sensitive adhesive sheet, a pressure-sensitive adhesive sheet whose adhesive force can be reduced by heating, irradiation with ultraviolet rays, or the like can be used. As one of them, a heat-peelable pressure-sensitive adhesive sheet including a pressure-sensitive adhesive layer containing thermally expandable microspheres that can be foamed by heating is known (for example, Patent Documents 1 to 4). In this heat-peelable pressure-sensitive adhesive sheet, the heat-expandable microspheres are foamed by heating and irregularities are generated on the surface of the pressure-sensitive adhesive layer. As a result, the pressure-sensitive adhesive force is reduced and expresses excellent releasability.

  However, when a ceramic capacitor is processed using the conventional heat-peelable pressure-sensitive adhesive sheet as a temporary fixing sheet, unevenness occurs on the sticking surface of the ceramic capacitor during the pressing process, and the unevenness remains in the obtained chip. . A chip having irregularities on the surface is likely to be mounted in an inclined state, causing a problem of poor connection. This problem becomes conspicuous with the miniaturization and high capacity (high stacking) of chips.

JP-A-56-61468 JP-A-56-61469 JP 60-252681 A JP 2002-361618 A

  The present invention has been made in order to solve the above-described conventional problems. The object of the present invention is to achieve both adhesiveness and peelability, prevent misalignment of the adherend, and adherence. It is providing the adhesive sheet which can reduce the unevenness | corrugation which arises on the sticking surface of a body.

The pressure-sensitive adhesive sheet of the present invention is a pressure-sensitive adhesive sheet including a pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer includes a pressure-sensitive adhesive and thermally expandable microspheres that can be foamed at a predetermined temperature. The average particle size at 25 ° C. is 10 μm or less, the content ratio of the thermally expandable microspheres is 15% by weight or more, and is 20 ° C. lower than the foaming temperature of the thermally expandable microspheres. The elastic modulus of the pressure-sensitive adhesive layer by a nanoindentation method is 0.6 MPa to 30 MPa.
In one embodiment, the elastic modulus by the nanoindentation method of the said adhesive layer in the temperature lower 50 degreeC than the foaming temperature of the said thermally expansible microsphere is 5 MPa-600 MPa.
In one embodiment, at 20 ° C. lower temperature than the foaming temperature of the heat-expandable microspheres, for elastic modulus E ₂₀ by the nanoindentation method of the pressure-sensitive adhesive layer, from the foaming temperature of the heat-expandable microspheres The ratio (E ₅₀ / E ₂₀ ) of the elastic modulus E ₅₀ by the nanoindentation method of the pressure-sensitive adhesive layer at a temperature lower by 50 ° C. is 1.1 or more.
In one embodiment, the gel fraction of the said adhesive layer is 50% or more.
In one embodiment, the thickness of the said adhesive layer is 5 micrometers-300 micrometers.
In one embodiment, the pressure-sensitive adhesive sheet of the present invention further includes a base material layer, and the pressure-sensitive adhesive layer is disposed on one side or both sides of the base material layer.
In one embodiment, the pressure-sensitive adhesive layer includes a rubber-based pressure-sensitive adhesive, and the base polymer constituting the rubber-based pressure-sensitive adhesive includes a structural unit derived from styrene.
In one embodiment, the glass transition temperature (Tg) of the base polymer which comprises the said rubber-type adhesive is -80 degreeC--30 degreeC.
In one embodiment, the pressure-sensitive adhesive sheet of the present invention further includes an elastic layer disposed on one side of the pressure-sensitive adhesive layer.
In one embodiment, the pressure sensitive adhesive sheet of the present invention is further provided with an elastic layer arranged between the pressure sensitive adhesive layer and the base material layer.
In one embodiment, the elastic layer has a thickness of 3 μm to 200 μm.
In one embodiment, the pressure-sensitive adhesive sheet is used as a temporary fixing sheet when cutting an electronic component material.
In one embodiment, the pressure-sensitive adhesive sheet is used as a temporary fixing sheet when cutting a ceramic capacitor material.
According to another aspect of the present invention, a method for manufacturing an electronic component is provided. This method for manufacturing an electronic component includes a step of attaching an electronic component material to the pressure-sensitive adhesive sheet and a step of cutting the electronic component material.

  According to the present invention, by including a pressure-sensitive adhesive layer containing a specific amount of thermally expandable microspheres of a specific size and having an elastic modulus within a specific range before the thermally expandable microspheres are foamed. Thus, it is possible to provide a pressure-sensitive adhesive sheet in which both the adhesiveness and the peelability are compatible and the unevenness generated on the adhesion surface of the adherend can be reduced. Furthermore, when the pressure-sensitive adhesive sheet of the present invention has the above elastic modulus of the pressure-sensitive adhesive layer in a specific range, when the adherend is stuck and then pressed, the pressure-sensitive adhesive layer is prevented from being displaced and covered. It is possible to reduce the displacement of the kimono. Such an adhesive sheet is used, for example, as a temporary fixing sheet in processing of a ceramic capacitor, and can contribute to an improvement in cutting accuracy when the ceramic capacitor is cut and separated.

(A) And (b) is a schematic sectional drawing of the adhesive sheet by one Embodiment of this invention. (A) And (b) is a schematic sectional drawing of the adhesive sheet by one Embodiment of this invention.

A. Outline of pressure-sensitive adhesive sheet The pressure-sensitive adhesive sheet of the present invention includes a pressure-sensitive adhesive layer. The pressure-sensitive adhesive sheet of the present invention may be composed of only the pressure-sensitive adhesive layer, and may further include any appropriate layer in addition to the pressure-sensitive adhesive layer. As a layer other than the pressure-sensitive adhesive layer, for example, a base material layer that can function as a support (C term described later), an elastic layer that can impart elasticity to the pressure-sensitive adhesive sheet (D term described later), and can be peeled on the pressure-sensitive adhesive layer. Separator (arranged later E) and the like. In addition to the pressure-sensitive adhesive layer, another pressure-sensitive adhesive layer may be further provided. The other pressure-sensitive adhesive layer may have a known configuration.

  The pressure-sensitive adhesive layer provided in the pressure-sensitive adhesive sheet of the present invention includes thermally expandable microspheres. The thermally expandable microspheres can foam at a predetermined temperature. In the pressure-sensitive adhesive layer containing such thermally expandable microspheres, the heat-expandable microspheres are foamed by heating, whereby unevenness is generated on the pressure-sensitive adhesive surface (that is, the pressure-sensitive adhesive layer surface), and the adhesive force is reduced or disappears. . When the pressure-sensitive adhesive sheet of the present invention is used, for example, as a temporary fixing sheet for a workpiece when processing an electronic component (for example, a ceramic capacitor), it is necessary for temporary fixing when the workpiece is subjected to predetermined processing. When the pressure-sensitive adhesive sheet is developed and the pressure-sensitive adhesive sheet is peeled from the processed product after processing, the pressure-sensitive adhesive force is reduced or disappeared by heating, and good peelability is exhibited.

  The adhesive force when the adhesive surface of the pressure-sensitive adhesive sheet of the present invention is adhered to a polyethylene terephthalate film (for example, 25 μm in thickness) before the thermally expandable microspheres are foamed at an environmental temperature of 25 ° C. is preferably 0. .2N / 20mm or more, more preferably 0.2N / 20mm to 20N / 20mm, and still more preferably 2N / 20mm to 10N / 20mm. If it is such a range, the adhesive sheet useful as a sheet | seat for temporary fixing used for manufacture of an electronic component can be obtained, for example. In the present specification, the adhesive strength refers to an adhesive strength measured by a method according to JIS Z 0237: 2000 (bonding condition: 2 kg roller 1 reciprocation, peeling speed: 300 mm / min, peeling angle 180 °).

  The thickness of the pressure-sensitive adhesive sheet of the present invention is preferably 30 μm to 500 μm, more preferably 40 μm to 300 μm.

B. Pressure-sensitive adhesive layer The pressure-sensitive adhesive layer includes a pressure-sensitive adhesive for imparting pressure-sensitive adhesive properties and thermally expandable microspheres.

  The elastic modulus according to the nanoindentation method of the pressure-sensitive adhesive layer at a temperature 20 ° C. lower than the foaming temperature of the thermally expandable microspheres is 0.6 MPa to 30 MPa. The elastic modulus by the nano-indentation method means that the load applied to the indenter and the depth of indentation when the indenter is pushed into the sample (location where no thermally expandable microspheres are present) are continuous during loading and unloading. It is determined from the obtained load-indentation depth curve. In this specification, the elastic modulus by the nanoindentation method means an elastic modulus measured as described above under the measurement conditions of load: 1 mN, load / unloading speed: 0.1 mN / s, and holding time: 1 s.

  In the present specification, the “foaming temperature of the thermally expandable microsphere” is a heating temperature at which the expansion of the thermally expandable microsphere can be maximized by heating for 1 minute, in other words, when heated for more than 1 minute. It means the lower limit temperature of the temperature range in which the thermally expandable microspheres burst. The “foaming temperature of the thermally expandable microsphere” is, for example, 70 ° C. to 250 ° C. as described later. “One minute heating” can be performed, for example, by placing the thermally expandable microspheres directly on a hot plate. The “temperature lower by 20 ° C. than the foaming temperature of the thermally expandable microsphere” can correspond to, for example, the temperature at which the green sheets on which the electrodes are formed are stacked and pressed during processing of the ceramic capacitor. . The pressure-sensitive adhesive layer was pressurized at an environmental temperature in the vicinity of the temperature because the elastic modulus at the “temperature lower by 20 ° C. than the foaming temperature of the thermally expandable microsphere” is 0.6 MPa or more (for example, , Pressurizing at 0.3 MPa) is difficult to deform, and the displacement is suppressed. If a pressure-sensitive adhesive sheet having such a pressure-sensitive adhesive layer is used as a temporarily fixed sheet for processing a ceramic capacitor, for example, it is possible to prevent positional displacement of the ceramic capacitor as an adherend during lamination and pressurization. Cutting accuracy when cutting and separating ceramic capacitors is improved. On the other hand, when the elastic modulus is larger than 30 MPa, there is a possibility that sufficient adhesive force cannot be obtained. That is, in the present invention, by setting the elastic modulus within the specific range, it is possible to prevent the displacement of the adherend while having sufficient adhesive force, and temporarily fix electronic components such as ceramic capacitors. Can be obtained.

  Moreover, if the said elasticity modulus is the said specific range, the effect of including a thermally expansible microsphere can be heightened. Specifically, the pressure-sensitive adhesive layer having an elastic modulus of 30 MPa or less hardly inhibits the expansion of the heat-expandable microsphere, and can easily exhibit peelability by heating. In addition, the pressure-sensitive adhesive layer having an elastic modulus of 0.6 MPa or more is hardly affected by the heat-expandable microspheres on the surface before foaming (that is, in a situation where adhesiveness is required), and adheres to the adherend. And can exhibit excellent adhesiveness, and can reduce unevenness (particularly unevenness generated at the time of thermocompression bonding) generated on the adherend surface of the adherend.

  The elastic modulus of the pressure-sensitive adhesive layer by the nanoindentation method at a temperature 20 ° C. lower than the foaming temperature of the thermally expandable microsphere is preferably 0.6 MPa to 25 MPa, more preferably 0.6 MPa to 20 MPa. More preferably, it is 2 MPa to 10 MPa, and particularly preferably 2 MPa to 5.5 MPa. If it is such a range, the said effect will become remarkable. The elastic modulus of the pressure-sensitive adhesive layer can be controlled by, for example, the gel fraction of the pressure-sensitive adhesive layer, the type of pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, and the additive (particularly, the crosslinking agent) added to the pressure-sensitive adhesive layer. it can.

  The elastic modulus of the pressure-sensitive adhesive layer at a temperature lower by 50 ° C. than the foaming temperature of the thermally expandable microspheres is preferably 5 MPa to 600 MPa, more preferably 10 MPa to 600 MPa, and still more preferably 20 MPa to 600 MPa, particularly preferably 20 MPa to 100 MPa, and most preferably 20 MPa to 50 MPa. If it is such a range, the said effect will become remarkable.

At 20 ° C. lower temperature than the foaming temperature of the heat-expandable microspheres, for elastic modulus E ₂₀ by the nanoindentation method of the pressure-sensitive adhesive layer, at 50 ° C. lower temperature than the foaming temperature of the heat-expandable microspheres, wherein The ratio (E ₅₀ / E ₂₀ ) of the elastic modulus E ₅₀ by the nanoindentation method of the pressure-sensitive adhesive layer is preferably 1.1 or more, more preferably 5 or more, and further preferably 7 to 15. If it is such a range, the said effect will become remarkable.

  The surface roughness Ra of the pressure-sensitive adhesive layer before foaming the thermally expandable microspheres at an environmental temperature of 25 ° C. is preferably 500 nm or less, more preferably 400 nm or less, and even more preferably 300 nm or less. It is. If it is such a range, the adhesive sheet which can reduce the unevenness | corrugation which arises on the sticking surface of a to-be-adhered body can be obtained. The surface roughness Ra can be measured according to JIS B 0601: 1994.

  The surface roughness Ra of the pressure-sensitive adhesive layer after heating the pressure-sensitive adhesive sheet of the present invention to foam thermally expandable microspheres is preferably 3 μm or more, more preferably 5 μm or more. Within such a range, a pressure-sensitive adhesive sheet can be obtained in which the adhesive strength decreases or disappears after heating and the adherend can be easily peeled off. Here, the surface roughness Ra of the pressure-sensitive adhesive layer refers to the surface roughness Ra of the pressure-sensitive adhesive layer after being heated in the absence of an adherend.

  The gel fraction of the pressure-sensitive adhesive layer is preferably 50% or more, more preferably 55% or more, still more preferably 60% or more, and particularly preferably 60% to 95%. If it is such a range, the adhesive layer which has the elasticity modulus of the said range can be obtained easily. Moreover, if the gel fraction is within the above range, the pressure-sensitive adhesive layer has an appropriate fluidity, can prevent the displacement of the adherend, and against the expansion of the thermally expandable microspheres at the time of peeling. It exhibits good followability and can exhibit excellent peelability. In addition, in this specification, the measuring method of a gel fraction is mentioned later.

  The thickness of the pressure-sensitive adhesive layer is preferably 5 μm to 300 μm, more preferably 15 μm to 250 μm, still more preferably 30 μm to 100 μm, and particularly preferably 30 μm to 60 μm.

B-1. Adhesive Any appropriate adhesive can be used as the adhesive constituting the adhesive layer as long as the effects of the present invention are obtained. Examples of the adhesive include acrylic adhesive, silicone adhesive, vinyl alkyl ether adhesive, polyester adhesive, polyamide adhesive, urethane adhesive, fluorine adhesive, and styrene-diene block co-polymer. Examples thereof include a polymer-based pressure-sensitive adhesive and an active energy ray-curable pressure-sensitive adhesive. Among these, an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, or a silicone-based pressure-sensitive adhesive is preferable, and an acrylic pressure-sensitive adhesive or a rubber-based pressure-sensitive adhesive is more preferable.

(Acrylic adhesive)
Examples of the acrylic pressure-sensitive adhesive include, for example, an acrylic pressure-sensitive adhesive based on an acrylic polymer (homopolymer or copolymer) using one or more (meth) acrylic acid alkyl esters as monomer components. Etc. Specific examples of alkyl (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth ) Isobutyl acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate , 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, (meth) acrylic acid Undecyl, dodecyl (meth) acrylate, tridecyl (meth) acrylate, (me ) Tetradecyl acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate (meta) ) Acrylic acid C1-20 alkyl ester. Especially, the (meth) acrylic-acid alkylester which has a C4-C18 linear or branched alkyl group may be used preferably.

  The acrylic polymer is a unit corresponding to another monomer component copolymerizable with the (meth) acrylic acid alkyl ester, if necessary, for the purpose of modifying cohesion, heat resistance, crosslinkability and the like. May be included. Examples of such monomer components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride, itaconic anhydride Acid anhydride monomers such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, hydroxyhexyl (meth) acrylate, hydroxyoctyl (meth) acrylate, (meth) Hydroxyl group-containing monomers such as hydroxydecyl acrylate, hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl methacrylate; styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide Sulfonic acid group-containing monomers such as 2-methylpropanesulfonic acid, (meth) acrylamidepropanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalenesulfonic acid; (meth) acrylamide, N, N-dimethyl (meta ) (N-substituted) amide monomers such as acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide; aminoethyl (meth) acrylate, (meth) acrylic (Meth) acrylic acid aminoalkyl monomers such as N, N-dimethylaminoethyl acid, t-butylaminoethyl (meth) acrylate; (meth) methacrylic acid (meth) acrylate, ) Alkoxy acrylate Rutile monomers; maleimide monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-phenylmaleimide; N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octyl Itaconimide monomers such as itaconimide, N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, N-laurylitaconimide; N- (meth) acryloyloxymethylenesuccinimide, N- (meth) acryloyl-6-oxyhexamethylene Succinimide monomers such as succinimide and N- (meth) acryloyl-8-oxyoctamethylenesuccinimide; vinyl acetate, vinyl propionate, N-vinyl pyrrolidone, methyl vinyl pyro Vinyl such as lidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholine, N-vinylcarboxylic amides, styrene, α-methylstyrene, N-vinylcaprolactam Cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; epoxy group-containing acrylic monomers such as glycidyl (meth) acrylate; polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, (meth) acrylic acid Glycol acrylic ester monomers such as methoxyethylene glycol and (meth) acrylic acid methoxypolypropylene glycol; (meth) acrylic acid tetrahydrofur Acrylic acid ester monomers having heterocycles such as ril, fluorine (meth) acrylate, silicone (meth) acrylate, halogen atoms, silicon atoms, etc .; hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate , (Poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa Polyfunctional monomers such as (meth) acrylates, epoxy acrylates, polyester acrylates, urethane acrylates; olefinic monomers such as isoprene, butadiene, isobutylene; And vinyl ether monomers such as vinyl ether. These monomer components may be used alone or in combination of two or more.

  The acrylic polymer preferably contains a monomer a having a glass transition temperature (Tg) of −20 ° C. or higher when the polymer is a single polymer. In the acrylic polymer, the content ratio of the structural unit derived from the monomer a is preferably 30 parts by weight or more, more preferably 50 parts by weight or more, further preferably 100 parts by weight of the acrylic polymer. It is 70 parts by weight or more, and particularly preferably 70 parts by weight to 100 parts by weight. If monomer a which can form a polymer having a high glass transition temperature is used, a highly elastic pressure-sensitive adhesive layer can be formed. The pressure-sensitive adhesive sheet having such a pressure-sensitive adhesive layer can prevent the displacement of the adherend. If the pressure-sensitive adhesive sheet is used as a temporarily fixed sheet for manufacturing a ceramic capacitor, for example, it is possible to prevent displacement of the ceramic capacitor as an adherend during lamination and pressurization, and as a result, the cutting accuracy of the ceramic capacitor is improved. To do.

  Specific examples of the monomer a include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic. Isobutyl acid, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, acrylic acid, methacrylic acid, carboxyethyl Acrylate, carboxypentyl acrylate, hydroxybutyl methacrylate, hydroxyhexyl (meth) acrylate, N-cyclohexylmaleimide, N-isopropylmaleimide, N-phenylmaleimide, N-methylitaconimide, N-ethylitaconimide, N- Butyl Itaconi N- (meth) acryloyloxymethylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, vinyl acetate, vinyl propionate, N-vinyl pyrrolidone, methyl vinyl pyrrolidone, vinyl pyridine, vinyl piperidone, vinyl pyrimidine, Vinyl piperazine, vinyl pyrazine, vinyl pyrrole, vinyl imidazole, vinyl oxazole, vinyl morpholine, N-vinyl carboxylic amides, styrene, α-methyl styrene, N-vinyl caprolactam, acrylonitrile, methacrylonitrile, polyethylene (meth) acrylate Glycol, (meth) acrylic acid polypropylene glycol, hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, E) Propylene glycol di (meth) acrylate, isoprene, butadiene, isobutylene and the like.

(Rubber adhesive)
As the rubber-based pressure-sensitive adhesive, any appropriate pressure-sensitive adhesive can be used as long as the effects of the present invention are obtained. Examples of the rubber-based adhesive include natural rubber; polyisoprene rubber, butadiene rubber, styrene-butadiene (SB) rubber, styrene-isoprene (SI) rubber, styrene-isoprene-styrene block copolymer (SIS) rubber, styrene.・ Butadiene / styrene block copolymer (SBS) rubber, styrene / ethylene / butylene / styrene block copolymer (SEBS) rubber, styrene / ethylene / propylene / styrene block copolymer (SEPS) rubber, styrene / ethylene / propylene A rubber-based pressure-sensitive adhesive having a base polymer such as block copolymer (SEP) rubber, recycled rubber, butyl rubber, polyisobutylene rubber, or a modified rubber thereof is preferably used.

  The base polymer constituting the rubber-based pressure-sensitive adhesive preferably contains a styrene-derived structural unit, and more preferably is a block copolymer containing a styrene-derived structural unit. Specific examples of such base polymers include, for example, styrene / ethylene / propylene block copolymer (SEP) rubber, styrene / ethylene / butylene / styrene block copolymer (SEBS) rubber, styrene / isoprene / styrene block copolymer. Examples thereof include polymer (SIS) rubber, styrene / butadiene / styrene block copolymer (SBS) rubber, and the like. The content ratio of the structural unit derived from styrene in the base polymer constituting the rubber-based pressure-sensitive adhesive is preferably 10 parts by weight to 65 parts by weight, more preferably 15 parts by weight with respect to 100 parts by weight of the base polymer. ~ 60 parts by weight. If it is such a range, the adhesive layer which has moderate elasticity can be formed, the position shift of a to-be-adhered body can be prevented, and favorable peelability can be expressed.

  The glass transition temperature (Tg) of the base polymer constituting the rubber-based pressure-sensitive adhesive is preferably −80 ° C. to −30 ° C., more preferably −70 ° C. to −30 ° C., and further preferably −60 ° C. ~ -30 ° C. If a base polymer having such a glass transition temperature is used, a pressure-sensitive adhesive sheet capable of preventing the displacement of the adherend by forming a pressure-sensitive adhesive layer having appropriate elasticity can be obtained. If the pressure-sensitive adhesive sheet is used as a temporarily fixed sheet for manufacturing a ceramic capacitor, for example, it is possible to prevent displacement of the ceramic capacitor as an adherend during lamination and pressurization, and as a result, the cutting accuracy of the ceramic capacitor is improved. To do. In addition, the glass transition temperature (Tg) of the base polymer which comprises a rubber-type adhesive can be measured by differential scanning calorimetry (DSC).

In one embodiment, the base polymer which comprises the said rubber-type adhesive is acid-modified. Functional groups can be introduced by acid modification. By using any appropriate cross-linking agent and cross-linking the functional group as a cross-linking point, the fluidity of the base polymer is lowered. The pressure-sensitive adhesive layer containing a base polymer having low fluidity can follow the expansion without absorbing the influence of expansion of the thermally expandable microsphere. As a result, unevenness caused by thermally expandable microspheres expanded by heating is likely to appear on the surface of the adhesive layer, and preferable peelability can be obtained. Examples of the acid used for the acid modification include maleic acid and maleic anhydride. Further, the acid value of the base polymer modified with acid as described above is preferably 5 mg (CH ₃ ONa) / g or more, more preferably 7 mg (CH ₃ ONa) / g or more, and further preferably a _{7mg (CH 3 ONa) / g~25} (CH 3 ONa) / g. In addition, the acid value here means the weight (mg) of sodium methoxide (CH ₃ ONa) that neutralizes 1 g of the base polymer. The acid value of the base polymer can be measured according to JIS K0070: 1992.

(Silicone adhesive)
Any appropriate pressure-sensitive adhesive can be used as the silicone-based pressure-sensitive adhesive as long as the effects of the present invention can be obtained. As the silicone-based pressure-sensitive adhesive, for example, a silicone-based pressure-sensitive adhesive having a base polymer such as silicone rubber or silicone resin containing organopolysiloxane is preferably used. As the base polymer constituting the silicone-based pressure-sensitive adhesive, a base polymer obtained by crosslinking the above silicone rubber or silicone resin may be used. In this specification, the distinction between “silicone rubber” and “silicone resin” is “Technical Information Association, Adhesive (Film / Tape) Material Design and Functional Addition 1st Edition, September 30, 2009 222. “Page 228”. That is, “silicone rubber” means a linear silicone composed of diorganosiloxane (D unit), and the silicone rubber has a viscosity of, for example, about 10,000 Pa · s. The “silicone resin” means a silicone having a branched structure containing triorganosyl hemioxane (M unit) and silicate (Q unit).

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

Examples of the silicone resin include organopolysiloxanes containing at least one constituent unit selected from R ₃ SiO _1/2 constituent units, SiO ₂ constituent units, RSiO _3/2 constituent units, and R ₂ SiO constituent units. (R is a monovalent hydrocarbon group or a hydroxyl group).

The silicone rubber and silicone resin can be used in combination. The weight ratio of the silicone rubber to the silicone resin (rubber: resin) in the silicone adhesive is preferably 100: 0 to 100: 220, more preferably 100: 0 to 100: 180, and even more preferably 100: 10-100: 100. The tackiness and holding power of the silicone pressure-sensitive adhesive increase as the content of the silicone resin increases. The silicone rubber and the silicone resin may be contained in the silicone-based pressure-sensitive adhesive as a simple mixture, or may be included in the silicone-based pressure-sensitive adhesive in a form in which the silicone rubber and the silicone resin are partially condensed. The weight ratio of the silicone rubber to the silicone resin in the silicone-based pressure-sensitive adhesive is determined by ²⁹ Si-NMR measurement by the peak area ratio between the Q unit and the D unit (silicone rubber: silicone resin = D unit: Q unit). Can do.

  Preferably, the silicone pressure-sensitive adhesive contains a crosslinking agent. Examples of the crosslinking agent contained in the silicone-based pressure-sensitive adhesive include siloxane-based crosslinking agents and peroxide-based crosslinking agents. Any appropriate crosslinking agent may be used as the peroxide-based crosslinking agent. Examples of the peroxide-based crosslinking agent include benzoyl peroxide, t-butyl peroxybenzoate, and dicumyl peroxide. Examples of the siloxane-based crosslinking agent include polyorganohydrogensiloxane. The polyorganohydrogensiloxane preferably has two or more hydrogen atoms bonded to silicon atoms. The polyorganohydrogensiloxane preferably has an alkyl group, a phenyl group or a halogenated alkyl group as a functional group bonded to a silicon atom, and more preferably has a methyl group in view of ease of synthesis and handling. .

(Additive)
The pressure-sensitive adhesive may contain any appropriate additive as required. Examples of the additive include a crosslinking agent, a tackifier, a plasticizer, a pigment, a dye, a filler, an anti-aging agent, a conductive material, an antistatic agent, an ultraviolet absorber, a light stabilizer, a release adjusting agent, and a softening agent. , Surfactants, flame retardants, antioxidants and the like.

  Any appropriate tackifier is used as the tackifier. As the tackifier, for example, a tackifier resin is used. Specific examples of tackifying resins include rosin tackifying resins (eg, unmodified rosin, modified rosin, rosin phenolic resin, rosin ester resin, etc.), terpene tackifying resins (eg, terpene resins, terpene phenols). Resin, styrene modified terpene resin, aromatic modified terpene resin, hydrogenated terpene resin), hydrocarbon tackifier resin (for example, aliphatic hydrocarbon resin, aliphatic cyclic hydrocarbon resin, aromatic resin) Hydrocarbon resins (eg, styrene resins, xylene resins, etc.), aliphatic / aromatic petroleum resins, aliphatic / alicyclic petroleum resins, hydrogenated hydrocarbon resins, coumarone resins, coumarone indene resins Etc.), phenolic tackifying resins (eg, alkylphenolic resins, xyleneformaldehyde resins, resoles, novos) Tsu, etc. h), ketone-based tackifying resins, polyamide-based tackifying resins, epoxy-based tackifying resins, such as an elastomer-based tackifying resins. Among these, rosin-based tackifier resins, terpene-based tackifier resins, or hydrocarbon-based tackifier resins (such as styrene resins) are preferable. You may use a tackifier individually or in combination of 2 or more types.

  The addition amount of the tackifier is preferably 5 to 100 parts by weight, more preferably 10 to 50 parts by weight with respect to 100 parts by weight of the base polymer.

  Examples of the crosslinking agent include an isocyanate crosslinking agent, an epoxy crosslinking agent, a melamine crosslinking agent, a peroxide crosslinking agent, a urea crosslinking agent, a metal alkoxide crosslinking agent, a metal chelate crosslinking agent, and a metal. Examples thereof include salt-based crosslinking agents, carbodiimide-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, and amine-based crosslinking agents. Of these, an isocyanate-based crosslinking agent or an epoxy-based crosslinking agent is preferable.

  Specific examples of the isocyanate-based crosslinking agent include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate; 2,4- Aromatic isocyanates such as tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, xylylene diisocyanate; trimethylolpropane / tolylene diisocyanate trimer adduct (trade name “Coronate L” manufactured by Nippon Polyurethane Industry Co., Ltd.), tri Methylolpropane / hexamethylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name “Coronate HL”), hexamethylene diisocyanate isocyanate Isocyanurate body (Nippon Polyurethane Industry Co., Ltd. under the trade name "Coronate HX") isocyanate adducts of the like; and the like. The content of the isocyanate-based crosslinking agent can be set to any appropriate amount depending on the desired adhesive strength, the elasticity of the adhesive layer, and the like. 1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight.

  Examples of the epoxy crosslinking agent include N, N, N ′, N′-tetraglycidyl-m-xylenediamine, diglycidylaniline, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane (Mitsubishi Gas). Manufactured by Kagaku Co., Ltd., trade name “Tetrad C”), 1,6-hexanediol diglycidyl ether (manufactured by Kyoeisha Chemical Co., trade name “Epolite 1600”), neopentyl glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., trade name “ Epolite 1500NP "), ethylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., trade name" Epolite 40E "), propylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Co., trade name" Epolite 70P "), polyethylene glycol diglycidyl ether (Japan) Product name “Epiol” -400 "), polypropylene glycol diglycidyl ether (Nippon Yushi Co., Ltd., trade name" Epiol P-200 "), sorbitol polyglycidyl ether (Nagase ChemteX Corporation, trade name" Denacol EX-611 "), glycerol polyglycidyl Ether (manufactured by Nagase ChemteX Corporation, trade name “Denacol EX-314”), pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether (manufactured by Nagase ChemteX Corporation, trade name “Denacol EX-512”), sorbitan polyglycidyl ether , Trimethylolpropane polyglycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxyethyl) isocyanurate, resor Emissions diglycidyl ether, bisphenol -S- diglycidyl ether, epoxy resins having two or more epoxy groups in the molecule. The content of the epoxy-based crosslinking agent can be set to any appropriate amount depending on the desired adhesive strength, the elasticity of the adhesive layer, and the like. It is 01 weight part-10 weight part, More preferably, it is 0.03 weight part-5 weight part.

  Any appropriate plasticizer can be used as the plasticizer. Specific examples of the plasticizer include, for example, a trimet acid ester plasticizer, a pyromellitic acid ester plasticizer, a polyester plasticizer, and an adipic acid plasticizer. Among these, trimellitic acid ester plasticizers (for example, trimellitic acid tri (n-octyl), trimellitic acid tri (2-ethylhexyl), etc.) or pyromellitic acid ester plasticizers (for example, pyromellitic acid ester plasticizers) Acid tetra (n-octyl), pyromellitic acid tetra (2-ethylhexyl) and the like. You may use a plasticizer individually or in combination of 2 or more types. The content of the plasticizer is preferably 1 part by weight to 20 parts by weight, and more preferably 1 part by weight to 5 parts by weight with respect to 100 parts by weight of the base polymer.

B-2. Thermally expandable microspheres The pressure-sensitive adhesive layer further includes thermally expandable microspheres. The pressure-sensitive adhesive sheet including the pressure-sensitive adhesive layer containing the heat-expandable microspheres is heated, whereby the heat-expandable microspheres expand or fire to cause unevenness on the adhesive surface, resulting in a decrease or disappearance of the adhesive force. To do. Such an adhesive sheet can be easily peeled off by heating.

  As the thermally expandable microsphere, any appropriate thermally expandable microsphere can be used as long as it is a microsphere that can expand or foam by heating. As the thermally expandable microsphere, for example, a microsphere in which a substance that easily expands by heating is encapsulated in an elastic shell can be used. Such thermally expandable microspheres can be produced by any appropriate method, for example, a coacervation method, an interfacial polymerization method, or the like.

  Examples of the material that easily expands when heated include propane, propylene, butene, normal butane, isobutane, isopentane, neopentane, normal pentane, normal hexane, isohexane, heptane, octane, petroleum ether, methane halide, tetraalkylsilane. And low-boiling-point liquids such as azodicarbonamide that is gasified by thermal decomposition.

  Examples of the substance constituting the shell include nitrile monomers such as acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethoxyacrylonitrile, fumaronitrile; acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, Carboxylic acid monomers such as citraconic acid; vinylidene chloride; vinyl acetate; methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, (Meth) acrylic acid esters such as isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, β-carboxyethyl acrylate; styrene monomers such as styrene, α-methylstyrene, chlorostyrene ; It includes polymer composed like; acrylamides, substituted acrylamides, methacrylamide, amide monomers such as substituted methacrylamide. 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, methyl methacrylate-acrylonitrile copolymer, acrylonitrile-methacrylonitrile-itaconic acid copolymer. A polymer etc. are mentioned.

  An inorganic foaming agent or an organic foaming agent may be used as the thermally expandable microsphere. Examples of the inorganic foaming agent include ammonium carbonate, ammonium hydrogen carbonate, sodium hydrogen carbonate, ammonium nitrite, sodium borohydride, various azides and the like. Examples of the organic foaming agent include chlorofluorinated alkane compounds such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate. Hydrazine compounds such as p-toluenesulfonyl hydrazide, diphenylsulfone-3,3′-disulfonyl hydrazide, 4,4′-oxybis (benzenesulfonyl hydrazide), allyl bis (sulfonyl hydrazide); p-toluylene sulfonyl semicarbazide, 4, Semicarbazide compounds such as 4′-oxybis (benzenesulfonyl semicarbazide); Triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; N, N′-dinitrosopentamethylenetetramine, N, '- dimethyl -N, N'-dinitrosoterephthalamide; etc. N- nitroso compounds, and the like.

  A commercially available product may be used as the thermally expandable microsphere. As specific examples of commercially available thermally expandable microspheres, trade names “Matsumoto Microsphere” manufactured by Matsumoto Yushi Seiyaku Co., Ltd. (grade: F-30, F-30D, F-36D, F-36LV, F-50, F-50D, F-65, F-65D, FN-100SS, FN-100SSD, FN-180SS, FN-180SSD, F-190D, F-260D, F-2800D) “Pancel” (grade: 053-40, 031-40, 920-40, 909-80, 930-120), “Die Foam” manufactured by Kureha Chemical Industries (grade: H750, H850, H1100, S2320D, S2640D, M330) , M430, M520), “Advancel” manufactured by Sekisui Chemical Co., Ltd. (grade: EML101, EMH204, EHM30) , EHM302, EHM303, EM304, EHM401, EM403, EM501) and the like.

  The average particle diameter of the thermally expandable microspheres before the foaming of the thermally expandable microspheres at an ambient temperature of 25 ° C. is 10 μm or less, preferably 1 μm to 10 μm, more preferably 3 μm to 10 μm. And more preferably 5 μm to 10 μm. By using heat-expandable microspheres having an average particle size of 10 μm or less, the influence of the heat-expandable microspheres before foaming of the heat-expandable microspheres (that is, the situation where the pressure-sensitive adhesive layer needs to be sticky) is achieved. It is difficult to occur on the surface of the adhesive layer, has high adhesiveness to the adherend and has excellent adhesiveness, and reduces unevenness (especially unevenness generated during thermocompression bonding) on the adherend surface of the adherend. An obtained pressure-sensitive adhesive sheet can be obtained. Heat-expandable microspheres having an average particle diameter of 1 μm or more can be expanded to a size sufficient for exhibiting peelability by heating. The average particle diameter of the thermally expandable microspheres can be controlled by, for example, conditions (for example, the number of stirring blade rotations and the polymerization temperature during polymerization) when the thermally expandable microspheres are polymerized. Moreover, when using commercially available thermally expansible microsphere, it can control by classification processes, such as a mesh process, a filter process, and a centrifugation process. In this specification, the average particle diameter is determined by observing the thermally expandable microspheres used or the thermally expandable microspheres taken out from the pressure-sensitive adhesive layer before heating using an optical microscope or an electron microscope. It can also be measured. The average particle diameter can be measured by a particle size distribution measurement method in a laser scattering method. More specifically, the average particle size is determined by dispersing the heat-expandable microspheres used in a predetermined solvent (for example, water) and then measuring the particle size distribution (for example, trade name “SALD-2000J” manufactured by Shimadzu Corporation). ).

  The foaming temperature of the thermally expandable microsphere is preferably 70 ° C to 250 ° C, more preferably 90 ° C to 210 ° C. If thermally expandable microspheres having a foaming temperature in such a range are used, when used as a temporary fixing sheet for processing an electronic component (for example, a ceramic capacitor), it does not foam at the processing temperature of the electronic component, and is adhesive. Can be formed.

  The thermally expandable microsphere preferably has an appropriate strength that does not rupture until the volume expansion coefficient is preferably 5 times or more, more preferably 7 times or more, and even more preferably 10 times or more. When such a heat-expandable microsphere is used, the adhesive force can be efficiently reduced by heat treatment.

The content ratio of the heat-expandable microspheres in the pressure-sensitive adhesive layer can be appropriately set according to the desired decrease in adhesive strength. The content ratio of the heat-expandable microspheres is 15% by weight or more, preferably 16% by weight or more with respect to the weight of the pressure-sensitive adhesive layer. The upper limit of the content ratio of the heat-expandable microspheres is preferably 60% by weight or less, more preferably 55% by weight or less, and further preferably 50% by weight or less with respect to the weight of the pressure-sensitive adhesive layer. If it is the above ranges, the adhesive sheet which shows favorable adhesiveness when processing an electronic component etc. and can peel an adherend easily at the time of a heating can be obtained. The content ratio of the heat-expandable microsphere is obtained by the following formula. The weight of the thermally expandable microsphere is determined by measuring the weight of the thermally expandable microsphere extracted from the pressure-sensitive adhesive layer.
Content ratio (% by weight) of thermally expandable microsphere = weight of thermally expandable microsphere / weight of pressure-sensitive adhesive layer × 100

  Further, the content ratio of the heat-expandable microspheres can also be represented by the area ratio of the heat-expandable microspheres measured from the cross section. When the cross-sectional area of the pressure-sensitive adhesive layer in a predetermined cross section is A and the cross-sectional area of the thermally expandable microspheres in the cross section is B, the ratio of the cross-sectional area B of the heat-expandable microspheres is the cross-sectional area A of the pressure-sensitive adhesive layer. On the other hand, it is preferably 5% or more, more preferably 7% or more, and further preferably 9% or more. The upper limit of the ratio of the cross-sectional area B of the thermally expandable microspheres is preferably 50% or less, more preferably 45% or less, still more preferably 40% or less with respect to the cross-sectional area A of the pressure-sensitive adhesive layer. is there. The ratio of the cross-sectional area B of the thermally expandable microsphere is determined by, for example, observing the cross section of the pressure-sensitive adhesive layer with an electron microscope (for example, “S-3400N low vacuum scanning electron microscope” manufactured by Hitachi Technologies, Ltd.). The obtained image can be obtained by appropriately processing. For example, when the image is output on paper, the paper weight a of the pressure-sensitive adhesive layer portion (that is, the whole pressure-sensitive adhesive layer including the heat-expandable microspheres), and the paper weight b obtained by cutting out only the heat-expandable microsphere portions, From this, it can be obtained by the equation b / a × 100.

B-3. Other components The pressure-sensitive adhesive layer may further contain any appropriate other component as long as the effects of the present invention are obtained. Examples of other components include beads. Examples of the beads include glass beads and resin beads. If such beads are added to the pressure-sensitive adhesive layer, the elastic modulus of the pressure-sensitive adhesive layer can be improved, and a pressure-sensitive adhesive sheet capable of processing a workpiece with higher accuracy can be obtained. The average particle diameter of the beads is, for example, 0.01 μm to 50 μm. The amount of beads added is, for example, 10 to 200 parts by weight, preferably 20 to 100 parts by weight, with respect to 100 parts by weight of the pressure-sensitive adhesive layer.

C. Base material layer In one embodiment, the pressure sensitive adhesive sheet of the present invention is provided with a pressure sensitive adhesive layer and a base material layer. Fig.1 (a) is a schematic sectional drawing of the adhesive sheet by one Embodiment of this invention. The pressure-sensitive adhesive sheet 100 includes a pressure-sensitive adhesive layer 10 and a base material layer 20 disposed on one side of the pressure-sensitive adhesive layer 10. FIG.1 (b) is a schematic sectional drawing of the adhesive sheet by another embodiment of this invention. The pressure-sensitive adhesive sheet 110 includes a pressure-sensitive adhesive layer 10 and a base material layer 20, and the pressure-sensitive adhesive layer 10 is disposed on both sides of the base material layer 20. The two pressure-sensitive adhesive layers may be the same pressure-sensitive adhesive layer or may be different pressure-sensitive adhesive layers. The base material layer has the above pressure-sensitive adhesive layer on one side and the other surface has another pressure-sensitive adhesive layer (that is, a pressure-sensitive adhesive layer different from the pressure-sensitive adhesive layer described in the above section B). May be.

  Examples of the substrate layer include a resin sheet, a nonwoven fabric, paper, a metal foil, a woven fabric, a rubber sheet, a foamed sheet, and a laminate thereof (particularly, a laminate including a resin sheet). Examples of the resin constituting the resin sheet include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, ethylene- Vinyl acetate copolymer (EVA), polyamide (nylon), wholly aromatic polyamide (aramid), polyimide (PI), polyvinyl chloride (PVC), polyphenylene sulfide (PPS), fluororesin, polyether ether ketone (PEEK) ) And the like. Examples of the nonwoven fabric include nonwoven fabrics made of natural fibers having heat resistance such as nonwoven fabrics including manila hemp; 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 the paper include Japanese paper and kraft paper.

  The thickness of the base material layer can be set to any appropriate thickness depending on the desired strength or flexibility and the purpose of use. The thickness of the base material 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 subjected to a surface treatment. Examples of the surface treatment include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, and coating treatment with a primer.

  Examples of the organic coating material include materials described in Plastic Hard Coat Material II (CMC Publishing Co., (2004)). Preferably, a urethane-based polymer, more preferably polyacryl urethane, polyester urethane, or a precursor thereof is used. This is because coating and application to the base material are simple, and various industrial products can be selected and obtained at low cost. The urethane polymer is, for example, a polymer composed of 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 contain a chain extender such as polyamine, an anti-aging agent, an oxidation stabilizer and the like as optional additives. Although the thickness of an organic coating layer is not specifically limited, For example, about 0.1 micrometer-10 micrometers are suitable, About 0.1 micrometer-5 micrometers are preferable, About 0.5 micrometer-5 micrometers are more preferable.

D. Elastic layer The pressure-sensitive adhesive sheet of the present invention may further comprise an elastic layer. Fig.2 (a) and FIG.2 (b) are schematic sectional drawings of the adhesive sheet by one Embodiment of this invention. The adhesive sheets 200 and 210 further include an elastic layer 30. Preferably, the elastic layer 30 can be provided on one side of the pressure-sensitive adhesive layer 10. As shown in FIG. 2B, when the pressure-sensitive adhesive sheet 210 includes the base material layer 20, the elastic layer 30 can be disposed between the pressure-sensitive adhesive layer 10 and the base material layer 20. By providing the elastic layer 30, the followability to the adherend is improved. In addition, when the pressure-sensitive adhesive sheet including the elastic layer 30 is heated at the time of peeling, deformation (expansion) in the surface direction of the pressure-sensitive adhesive layer is restricted, and deformation in the thickness direction is given priority. As a result, the peelability is improved.

  The elastic layer contains a base polymer, and the polymer exemplified as the base polymer constituting the pressure-sensitive adhesive layer can be used as the base polymer. The elastic layer may contain natural rubber, synthetic rubber, synthetic resin, or the like. Examples of the synthetic rubber and synthetic resin include nitrile, diene, and acrylic synthetic rubbers; thermoplastic elastomers such as polyolefins and polyesters; ethylene-vinyl acetate copolymers; polyurethanes; polybutadienes; Can be mentioned. The base polymer constituting the elastic layer may be the same as or different from the base polymer forming the pressure-sensitive adhesive layer. The elastic layer may be a foamed film formed from the base polymer. The foamed film can be obtained by any appropriate method. The elastic layer and the pressure-sensitive adhesive layer can be distinguished from each other by the difference in base polymer and / or the presence or absence of thermally expandable microspheres (the elastic layer does not include thermally expandable microspheres). More specifically, when the interface between the elastic layer and the pressure-sensitive adhesive layer can be identified by cross-sectional observation, such as when the elastic layer and the pressure-sensitive adhesive layer are formed from different base polymers, the elastic layer and the pressure-sensitive adhesive layer The boundary is defined by the interface. When the interface between the elastic layer and the pressure-sensitive adhesive layer cannot be identified by cross-sectional observation, the region where the thermally expandable microspheres are observed by cross-sectional observation is the pressure-sensitive adhesive layer.

  The elastic layer may contain any appropriate additive as required. Examples of the additive include a crosslinking agent, a vulcanizing agent, a tackifier, a plasticizer, a softening agent, a filler, and an antiaging agent. When a hard resin such as polyvinyl chloride is used as the base polymer, it is preferable to form an elastic layer having desired elasticity by using a plasticizer and / or a softening agent in combination.

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

  The tensile elastic modulus at 25 ° C. of the elastic layer is preferably 0.2 MPa to 500 MPa, more preferably 0.3 MPa to 500 MPa, and further preferably 0.5 MPa to 500 MPa. If it is such a range, the said function of an elastic layer can fully be exhibited. The tensile modulus can be measured according to JIS K 7161: 2008.

E. Separator The pressure-sensitive adhesive sheet of the present invention may further include a separator as necessary. The separator has a release surface on at least one surface, and can be provided to protect the pressure-sensitive adhesive layer and / or the elastic layer. The separator can be composed of any suitable material.

F. Manufacturing method of adhesive sheet The adhesive sheet of this invention can be manufactured by arbitrary appropriate methods. The pressure-sensitive adhesive sheet of the present invention is applied, for example, by directly applying a composition containing a pressure-sensitive adhesive and heat-expandable microspheres onto a base material layer (any appropriate base when a pressure-sensitive adhesive sheet not containing a base material layer is obtained). And a method of transferring a coating layer formed by coating a composition containing a pressure-sensitive adhesive and thermally expandable microspheres onto any appropriate substrate, and the like. The composition comprising the adhesive and the thermally expandable microspheres can include any suitable solvent. In addition, after forming an adhesive coating layer with a composition containing an adhesive, the thermally expandable microspheres are sprinkled on the adhesive coating layer, and then the thermally expandable microspheres are mixed with the laminator or the like. A pressure-sensitive adhesive layer containing thermally expandable microspheres may be formed by being embedded in the coating layer.

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

  Arbitrary appropriate coating methods may be employ | adopted as a coating method of each said composition. For example, each layer can be formed by drying after coating. Examples of the coating method include a coating method using a multi coater, a die coater, a gravure coater, an applicator, and the like. Examples of the drying method include natural drying and heat drying. The heating temperature in the case of heating and drying can be set to any appropriate temperature according to the characteristics of the substance to be dried.

G. Applications The pressure-sensitive adhesive sheet of the present invention can be suitably used as a sheet for temporarily fixing an electronic component material when manufacturing an electronic component. In one embodiment, the pressure-sensitive adhesive sheet of the present invention is used as a temporary fixing sheet when cutting an electronic component material. Examples of the electronic component material include a ceramic capacitor material. If an electronic component material such as a ceramic capacitor material is temporarily fixed on the pressure-sensitive adhesive sheet of the present invention, displacement of the material can be prevented, and as a result, the material can be cut with excellent accuracy.

H. Method for Manufacturing Electronic Component According to another aspect of the present invention, a method for manufacturing an electronic component is provided. The manufacturing method of the electronic component of this invention includes the process (sticking process) of sticking electronic component material to the said adhesive sheet, and the process (cutting process) of cut | disconnecting this electronic component material. Examples of the electronic component material include a ceramic capacitor material.

  In the attaching step, the electronic component material is preferably pressure-bonded. The pressure at the time of pressure bonding is preferably 0.1 MPa to 10 MPa, more preferably 0.3 MPa to 5 MPa. If the pressure-sensitive adhesive sheet of the present invention is used, deviation of the adherend (electronic component material) due to pressure bonding is small, and excellent cutting performance is realized. It is preferable to heat at the time of the said crimping | compression-bonding. The heating temperature is, for example, 50 ° C to 100 ° C.

  Any appropriate cutting method may be adopted as a cutting method in the cutting step.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by these Examples. The evaluation methods in the examples are as follows. In the following evaluation, an adhesive sheet from which the separator was peeled was used. In Examples, unless otherwise specified, “parts” and “%” are based on weight.

(1) Elastic modulus The pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples were cut in the thickness direction with a microtome, and the elastic modulus of the cut surface of the pressure-sensitive adhesive layer was measured with a nanoindenter. The cut surface that was about 3 μm away from the pressure-sensitive adhesive layer surface was used as the measurement target. An elastic modulus was obtained by numerically processing a displacement-load hysteresis curve obtained by pressing a probe (indenter) against a measurement object with software (triboscan) attached to a measurement device (average value of 10 measurements).
The nanoindenter apparatus and measurement conditions are as follows.
Apparatus and measurement conditions / apparatus: Nanoindenter; Tribodenter manufactured by Hystron Inc.
Measurement method: Single indentation method Measurement temperature: 110 ° C. (foaming temperature of thermally expandable microspheres −20 ° C.) and 80 ° C. (foaming temperature of thermally expandable microspheres −50 ° C.)
・ Push-in speed: about 1000nm / sec
・ Indentation depth: about 800nm
・ Tip: Diamond, Berkovich type (triangular pyramid type)

(2) Gel fraction 0.1 g of a sample sampled from the resin layer was wrapped in a mesh sheet and allowed to stand in 50 ml of toluene at room temperature for 1 week, so that toluene was immersed in the sample. Thereafter, the toluene-insoluble matter was taken out and dried at 70 ° C. for 2 hours, and the toluene-insoluble matter after drying was weighed.
The gel fraction of the resin layer was calculated from the weight of the sample before immersion in toluene and the weight of insoluble toluene by the following formula.
Gel fraction (%) = [(weight of insoluble matter in toluene) / (weight of sample before immersion in toluene)] × 100

(3) Heat peelability A laminated green sheet was attached on the pressure-sensitive adhesive layer of a pressure-sensitive adhesive sheet (20 mm × 20 mm). The adhesive sheet with the laminated green sheet thus obtained was heated at 130 ° C. for 1 minute. The peeling state of the green sheet after heating was confirmed visually. In Table 1, the case where the adhesive strength of the pressure-sensitive adhesive layer was lost and the green sheet was peeled off was marked with ◯, and the case where the pressure-sensitive adhesive layer had adhesive strength and the green sheet was not peeled off was marked with x.
In this evaluation and the following evaluation (5), a sample obtained as follows was used as a green sheet.
(Production of green sheets)
Dielectric toluene solution was obtained by adding 100 parts by weight of barium titanate powder, 30 parts by weight of polyvinyl butyral resin, 3 parts by weight of bis (2-ethylhexyl) phthalate to a toluene solvent, and mixing and dispersing with a ball mill disperser. . This solution was applied to the silicon release agent treated surface of MRF38 (Mitsubishi Polyester Film Co., Ltd., polyethylene terephthalate film with a silicone release agent treated surface (thickness 38 μm) using an applicator so that the thickness after solvent evaporation was 50 μm. The obtained sheet was laminated so that the thickness was 500 μm to obtain a green sheet.

(4) Evaluation of displacement of pressure-sensitive adhesive layer Pressurization operation (pressure: 0.3 MPa, time: 3 seconds) was repeatedly performed 100 times on the pressure-sensitive adhesive sheet (surface area: 2 cm ² ) at an environmental temperature of 70 ° C. . Then, the shift | offset | difference of the adhesive layer was evaluated on the following references | standards from the protrusion amount (length) of the adhesive layer on the basis of the base material layer.
○: The amount of protrusion is 0.05 mm or less. ×: The amount of protrusion exceeds 0.05 mm.

(5) Concavities and convexities generated on the surface of the green sheet after pressing A laminated green sheet was adhered to the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet and pressed at an environmental temperature of 70 ° C. (pressure: 0.3 MPa, time: 10 minutes) ). Thereafter, the laminated green sheet was peeled from the adhesive sheet, and the unevenness of the green sheet surface (sticking surface) was measured.
The unevenness of the green sheet was measured according to JIS B0601. Specifically, using an optical surface roughness meter (product name “Wyko NT9100” manufactured by Veeco Metrology Group), the surface roughness of the green sheet (Rt: maximum cross-sectional height of the roughness curve) under the following conditions: ) Was measured (average value of 5-point measurement).
・ Sample dimensions: 30mm width x 30mm length
Measurement range: 5.534 mm x 1.901 mm
・ Measurement mode: VSI
-Objective lens: 50 times-Eyepiece lens: 1 time

[Production Example 1] Preparation of thermally expandable microspheres Thermally expandable microspheres (manufactured by Matsumoto Yushi Seiyaku Co., Ltd., trade name “Matsumoto Microsphere F-50D”, foaming temperature: 130 ° C., average particle size: 14 μm) are subjected to centrifugal classification. The particles were classified by a machine to obtain thermally expandable microspheres A having an average particle diameter of 9 μm, thermally expandable microspheres B having an average particle diameter of 3 μm, and thermally expandable microspheres C having an average particle diameter of 11 μm. The average particle diameter of the thermally expandable microspheres was measured by observing 30 randomly selected particles with an electron microscope (trade name “S3400N low vacuum scanning electron microscope” manufactured by Hitachi Technologies, Ltd.).

[Example 1]
100 parts by weight of an acrylic copolymer (a copolymer of butyl acrylate and acrylic acid, butyl acrylate structural unit: acrylic acid structural unit = 100: 3 (weight ratio)), and an epoxy cross-linking agent (Mitsubishi Gas Chemical Co., Ltd., product) The name “Tetrad C”) 0.3 parts by weight and 210 parts by weight of toluene were mixed to prepare an elastic layer forming composition.
Maleic acid-modified styrene-ethylene-butylene-styrene block copolymer as a base polymer (styrene-based structural unit: ethylene-butylene structural unit = 30: 70 (weight ratio), acid value: 10 mg (CH ₃ ONa) / g) 100 weight 3 parts by weight of an epoxy-based crosslinking agent (trade name “Tetrad C”, manufactured by Mitsubishi Gas Chemical Company), 60 parts by weight of the thermally expandable microsphere A obtained in Production Example 1, and 320 parts by weight of toluene Were mixed to prepare a pressure-sensitive adhesive layer forming composition.
On the polyester film (thickness: 100 μm) as the base material layer, the elastic layer forming composition is applied and dried to form a laminate (1a) of the base material layer and the elastic layer (thickness: 20 μm). Got.
On the separator, the said adhesive layer formation composition was apply | coated and dried, and the laminated body (1b) of a separator and an adhesive layer (thickness: 50 micrometers) was obtained.
The laminate (1a) and the adhesive layer of the laminate (1b) are in contact with each other so that the laminates are bonded together to form an adhesive sheet (separator / adhesive layer / elastic layer / base material layer). Got.

[Example 2]
Acrylic copolymer (copolymer of 2-ethylhexyl acrylate, ethyl acrylate and 2-hydroxyethyl acrylate, 2-ethylhexyl acrylate structural unit: ethyl acrylate structural unit: 2-hydroxyethyl acrylate structural unit = 40: 60: 5 (weight ratio)) 100 parts by weight, 3 parts by weight of an isocyanate-based cross-linking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name “Coronate L”) and 210 parts by weight of toluene are mixed to form an elastic layer forming composition. A product was prepared.
Maleic acid-modified styrene-ethylene-butylene-styrene block copolymer as a base polymer (styrene-based structural unit: ethylene-butylene structural unit = 30: 70 (weight ratio), acid value: 10 mg (CH ₃ ONa) / g) 100 weight Part, 2.5 parts by weight of an epoxy-based crosslinking agent (trade name “Tetrad C” manufactured by Mitsubishi Gas Chemical Company), 80 parts by weight of the thermally expandable microsphere A obtained in Production Example 1, and a tackifier 50 parts by weight of an alkylphenol-based resin (trade name “TAMANOL 200N” manufactured by Arakawa Chemical Industries, Ltd.) and 350 parts by weight of toluene were mixed to prepare a pressure-sensitive adhesive layer forming composition.
On the polyester film (thickness: 50 μm) as the base material layer, the elastic layer forming composition is applied and dried to form a laminate (2a) of the base material layer and the elastic layer (thickness: 15 μm). Got.
On the separator, the said adhesive layer formation composition was apply | coated and dried, and the laminated body (2b) of a separator and an adhesive layer (thickness: 35 micrometers) was obtained.
Adhesive sheet (separator / adhesive layer / elastic layer / base material layer) by laminating both laminates so that the elastic layer of the laminate (2a) and the adhesive layer of the laminate (2b) are in contact with each other. Got.

[Example 3]
A pressure-sensitive adhesive sheet was obtained in the same manner as in Example 1 except that instead of the thermally expandable microsphere A, the thermally expandable microsphere B obtained in Production Example 1 was used.

[Example 4]
Acrylic copolymer (butyl acrylate, acrylonitrile, methyl methacrylate, and acrylic acid copolymer, butyl acrylate structural unit: acrylonitrile structural unit: methyl methacrylate: acrylic acid structural unit = 75: 20: 5 (weight ratio) ) 100 parts by weight, 30 parts by weight of a terpene phenol resin (trade name “YS Polystar T130” manufactured by Yashara Chemical Co., Ltd.) as a tackifier, and an epoxy crosslinking agent (trade name “Tetrad C” manufactured by Mitsubishi Gas Chemical Co., Ltd.) ) 1 part by weight, 25 parts by weight of thermally expandable microspheres A and 210 parts by weight of toluene were mixed to prepare a composition for forming an adhesive layer.
On the polyester film (thickness: 100 micrometers) as a base material layer, the said composition for adhesive layer formation was apply | coated and dried. Furthermore, a transparent separator was bonded onto the coating layer of the composition for forming an adhesive layer to obtain an adhesive sheet (separator / adhesive layer (thickness: 50 μm) / base material layer).

[Example 5]
Acrylic copolymer (acrylic acid-2-ethylhexyl, vinyl acetate, and acrylic acid copolymer, acrylic acid-2-ethylhexyl structural unit: vinyl acetate structural unit: acrylic acid structural unit = 50: 50: 5 (weight ratio)) 90 parts by weight, 20 parts by weight of a terpene phenol resin (trade name “YS Polystar T115” manufactured by Yashara Chemical Co., Ltd.) as a tackifier, and an epoxy crosslinking agent (trade name “Tetrad C” manufactured by Mitsubishi Gas Chemical Company) 1.5 parts by weight, 40 parts by weight of thermally expandable microspheres A, and 240 parts by weight of toluene were mixed to prepare a composition for forming an adhesive layer.
On the polyester film (thickness: 100 micrometers) as a base material layer, the said composition for adhesive layer formation was apply | coated and dried. Furthermore, a transparent separator was bonded onto the coating layer of the composition for forming an adhesive layer to obtain an adhesive sheet (separator / adhesive layer (thickness: 50 μm) / base material layer).

[Comparative Example 1]
Instead of the heat-expandable microsphere A, a heat-expandable microsphere (manufactured by Matsumoto Yushi Seiyaku Co., Ltd., trade name “Matsumoto Microsphere F-50D”, foaming temperature: 130 ° C., average particle size: 14 μm) was used. In the same manner as in Example 1, a pressure-sensitive adhesive sheet was obtained.

[Comparative Example 2]
A pressure-sensitive adhesive sheet was obtained in the same manner as in Example 1 except that instead of the thermally expandable microsphere A, the thermally expandable microsphere C obtained in Production Example 1 was used.

[Comparative Example 3]
Acrylic copolymer (2-ethylhexyl acrylate, ethyl acrylate and 2-hydroxyethyl acrylate copolymer, 2-ethylhexyl acrylate structural unit: ethyl acrylate structural unit: 2-hydroxyethyl acrylate structural unit = 20: 80: 5 (weight ratio)) 100 parts by weight, 3 parts by weight of an isocyanate-based cross-linking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name “Coronate L”) and 200 parts by weight of toluene are mixed to form an elastic layer forming composition. A product was prepared.
Acrylic copolymer as base polymer (copolymer of 2-ethylhexyl acrylate, ethyl acrylate and 2-hydroxyethyl acrylate, 2-ethylhexyl acrylate structural unit: ethyl acrylate structural unit: 2-hydroxyethyl acrylate = 20: 80: 5 (weight ratio)) 100 parts by weight, 20 parts by weight of the heat-expandable microsphere B obtained in Production Example 1, and isocyananeate-based crosslinking agent (trade name “Coronate L” manufactured by Nippon Polyurethane Industry Co., Ltd.) 2 parts by weight, 30 parts by weight of an alkylphenol resin (trade name “Tamanol 200N” manufactured by Arakawa Chemical Industries, Ltd.) and 350 parts by weight of toluene were mixed to prepare a composition for forming an adhesive layer.
On the polyester film (thickness: 100 μm) as the base material layer, the elastic layer forming composition is applied and dried to form a laminate (3a) of the base material layer and the elastic layer (thickness: 10 μm). Got.
On the separator, the pressure-sensitive adhesive layer-forming composition was applied and dried to obtain a laminate (3b) of the separator and the pressure-sensitive adhesive layer (thickness: 35 μm).
The laminate (3a) and the adhesive layer of the laminate (3b) are in contact with each other so that the laminates are bonded together to form an adhesive sheet (separator / adhesive layer / elastic layer / base material layer). Got.

[Comparative Example 4]
A pressure-sensitive adhesive sheet was obtained in the same manner as in Example 3 except that the content of the thermally expandable microsphere B was 15 parts by weight.

  As can be seen from Table 1, the pressure-sensitive adhesive sheet of the present invention can exhibit good peelability by heating, the pressure-sensitive adhesive layer is prevented from being displaced, and the unevenness generated on the green sheet as the adherend. Can be reduced.

DESCRIPTION OF SYMBOLS 10 Adhesive layer 20 Base material layer 30 Elastic layer

Claims (15)

An adhesive sheet comprising an adhesive layer,
The pressure-sensitive adhesive layer includes an acrylic pressure - sensitive adhesive and thermally expandable microspheres that can be foamed at a predetermined temperature,
The average particle diameter of the thermally expandable microspheres at 25 ° C. is 10 μm or less,
The content ratio of the thermally expandable microsphere is 15% by weight or more,
The elastic modulus according to the nanoindentation method of the pressure-sensitive adhesive layer at a temperature 20 ° C. lower than the foaming temperature of the thermally expandable microsphere is 0.6 MPa to 30 MPa.
Adhesive sheet.   The pressure-sensitive adhesive sheet according to claim 1, wherein the pressure-sensitive adhesive layer has an elastic modulus of 5 MPa to 600 MPa at a temperature lower by 50 ° C. than the foaming temperature of the thermally expandable microspheres. At 20 ° C. lower temperature than the foaming temperature of the thermally expandable microspheres, for elastic modulus E ₂₀ by the nanoindentation method of the pressure-sensitive adhesive layer, at 50 ° C. lower temperature than the foaming temperature of the heat-expandable microspheres, wherein the ratio of the elastic modulus _{E 50} by the nanoindentation method of the pressure-sensitive adhesive layer _(E 50 _/ E ₂₀₎ is 1.1 or more, the pressure-sensitive adhesive sheet according to claim 1 or 2.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer has a gel fraction of 50% or more.   The pressure-sensitive adhesive sheet according to claim 1, wherein the pressure-sensitive adhesive layer has a thickness of 5 μm to 300 μm. A base layer,
The pressure-sensitive adhesive layer is disposed on one side or both sides of the base material layer,
The pressure-sensitive adhesive sheet according to any one of claims 1 to 5. The pressure-sensitive adhesive sheet according to any one of claims 1 to 6, wherein the acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive having butyl (meth) acrylate as a base polymer. The pressure sensitive adhesive sheet according to claim 7 in which said base polymer contains a structural unit derived from acrylic acid or methacrylic acid. The pressure-sensitive adhesive sheet according to any one of claims 1 to 8, wherein the acrylic pressure-sensitive adhesive further comprises a terpene phenol-based tackifier resin. Further comprising an elastic layer disposed on one side of the pressure-sensitive adhesive layer, pressure-sensitive adhesive sheet according to any one of claims 1 to 9. Further comprising an elastic layer disposed between the base layer and the pressure-sensitive adhesive layer, pressure-sensitive adhesive sheet according to claim 6 to 9. The pressure sensitive adhesive sheet according to claim 10 or 11 whose thickness of said elastic layer is 3 micrometers-200 micrometers. The pressure-sensitive adhesive sheet according to any one of claims 1 to 12 , which is used as a temporary fixing sheet for cutting an electronic component material. Used as the temporary fixing sheet when cutting the ceramic capacitor materials, pressure-sensitive adhesive sheet according to any one of claims 1 to 12. A step of attaching an electronic component material to the pressure-sensitive adhesive sheet according to any one of claims 1 to 12 ,
Cutting the electronic component material.
Manufacturing method of electronic components.

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