WO2020129987A1 - Adhesive tape and method for manufacturing electronic component - Google Patents

Abstract

The purpose of the present invention is to provide: an adhesive tape which can be used in a support body which does not transmit light in manufacturing of an electronic component and, even when subjected to high-temperature treatment, does not easily detach from an adherend or the support body and suppresses adhesive residue; and a method for manufacturing an electronic component using the adhesive tape. This adhesive tape has a non-ultraviolet curable adhesive layer and an ultraviolet curable adhesive layer laminated on the non-ultraviolet curable adhesive layer. The non-ultraviolet curable adhesive layer has a tensile strength at 23°C of 5.0 N/10 mm to 20.0 N/10 mm. The non-ultraviolet curable adhesive layer has an amount of outgassing of 10000 ppm or less when heated at 260°C for 15 minutes.

Description

Adhesive tape and electronic component manufacturing method

The present invention relates to an adhesive tape and a method for manufacturing an electronic component using the adhesive tape.

In the manufacturing process of semiconductor chips, an adhesive tape is used to facilitate handling during processing of wafers and semiconductor chips and to prevent damage. For example, when a thick film wafer cut out from a high-purity silicon single crystal or the like is ground to a predetermined thickness to form a thin film wafer, grinding is performed after adhering an adhesive tape to the thick film wafer.

The adhesive composition used for such a pressure-sensitive adhesive tape has high adhesiveness enough to firmly fix an adherend such as a wafer or a semiconductor chip during a processing step, and also has a high adhesiveness after the end of the step. It is required that it can be peeled off without damaging the adhered body (hereinafter, also referred to as “highly adhesive and easy peeling”).
As an adhesive composition that achieves high adhesion and easy peeling, Patent Document 1 discloses a pressure-sensitive adhesive tape using a photocurable pressure-sensitive adhesive that is cured by irradiation with light such as ultraviolet rays to reduce the adhesive strength. .. By using a photocurable adhesive as the adhesive, the adherend can be reliably fixed during the processing step, and the adhesive can be easily peeled off by irradiating with ultraviolet rays or the like.

Japanese Patent Laid-Open No. 5-32946

In recent years, due to the thinning and miniaturization of semiconductor products, the substrate has been thinned to 100 μm or less (hereinafter, the thinned substrate is referred to as a thin substrate), and in order to prevent warpage and damage in manufacturing the substrate, Adhesive tape is used. In the production of such a thin substrate, a base material such as a polyimide film, which is the base of the substrate, is fixed to a support through a non-support type adhesive tape, and then a process such as wiring is performed. However, the support used for manufacturing a thin substrate is often an opaque material such as copper, aluminum, or glass epoxy from the viewpoint of cost and handleability. With such an opaque support, a conventional photocurable adhesive is used. There is a problem that the adhesive tape using the agent cannot be cured. For this problem, an adhesive tape having a curable adhesive layer and a non-curable adhesive layer has been proposed. Even when the support is opaque, the adhesive tape is hardened by attaching the curable adhesive layer to an adherend such as a thin substrate and curing it, and then attaching the non-curable adhesive layer to the support. Can be made.

On the other hand, in the manufacturing process of electronic components such as a thin substrate, a high temperature treatment in which heat of 150° C. or higher is applied may be performed. When a pressure-sensitive adhesive tape having a conventional curable pressure-sensitive adhesive layer and a non-curable pressure-sensitive adhesive layer is used in a process involving such high-temperature treatment, the non-curable pressure-sensitive adhesive layer cannot withstand heat and is a support. May peel off from. Since the temperature of high-temperature treatment is increasing with the progress of technology, there is a demand for an adhesive tape that can be used even for an opaque support and has further heat resistance.

INDUSTRIAL APPLICABILITY The present invention can be used for a support that does not transmit light in the production of electronic components, and can prevent peeling and adhesive residue from an adherend and a support even when high-temperature treatment is performed. An object of the present invention is to provide a tape and a method for manufacturing an electronic component using the adhesive tape.

A first aspect of the present invention is a pressure-sensitive adhesive tape having a non-ultraviolet curable pressure-sensitive adhesive layer and an ultraviolet-curable pressure-sensitive adhesive layer laminated on the non-ultraviolet curable pressure-sensitive adhesive layer, wherein the non-ultraviolet curable pressure-sensitive adhesive is used. The agent layer has a tensile strength at 23° C. of 5.0 N/10 mm or more and 20.0 N/10 mm or less, and an outgas amount of 10,000 ppm or less when the non-ultraviolet curable pressure-sensitive adhesive layer is heated at 260° C. for 15 minutes. It is an adhesive tape.
A second aspect of the present invention is a pressure-sensitive adhesive tape having a non-ultraviolet curable pressure-sensitive adhesive layer and an ultraviolet-curable pressure-sensitive adhesive layer laminated on the non-ultraviolet curable pressure-sensitive adhesive layer, wherein the non-ultraviolet curable pressure-sensitive adhesive is used. The amount of outgas when the agent layer is heated at 260° C. for 15 minutes is 10,000 ppm or less, and the non-ultraviolet curable pressure-sensitive adhesive layer has a carbon number of an alkyl group of 4 to 12 (A′) as a base polymer. A (meth)acrylic copolymer containing 92 to 97% by weight of a (meth)acrylic acid alkyl ester as a constituent component, (B) an epoxy compound having a tertiary amine structure as a curing agent, and (C) a filler. It is an adhesive tape contained.
The present invention is described in detail below.

The adhesive tape of the present invention has a non-ultraviolet curable adhesive layer and an ultraviolet curable adhesive layer laminated on the non-ultraviolet curable adhesive layer.
Since the pressure-sensitive adhesive tape has an ultraviolet-curable adhesive layer, it can be attached to an adherend with sufficient adhesive force to protect the adherend, and by curing the ultraviolet-curable adhesive layer after attachment, high temperature Even when the treatment is performed, the adherend can be surely protected. Further, after the protection is no longer required, the adhesive tape can be easily peeled off without damaging the adherend. Furthermore, since the adhesive tape has a non-ultraviolet curable adhesive layer, the ultraviolet curable adhesive layer is attached to an adherend, and the non-ultraviolet curable adhesive layer is cured after the ultraviolet curable adhesive layer is cured. Since it can be attached to the support, the ultraviolet-curable pressure-sensitive adhesive layer can be cured even when the support is opaque. From the viewpoint of simplifying the manufacturing process, the ultraviolet-curable pressure-sensitive adhesive layer may be cured by irradiating ultraviolet rays immediately after attaching the adhesive tape to the adherend.

In a preferred embodiment of the present invention, the non-UV curable pressure-sensitive adhesive layer is UV transparent. Here, the ultraviolet transmittance means that the light absorption wavelength band of the ultraviolet polymerization initiator contained in the ultraviolet curing adhesive layer and the wavelength band of the non-ultraviolet curing adhesive layer transmitting light overlap. Particularly, it is preferable that the light absorption wavelength band of the ultraviolet polymerization initiator and the wavelength band of the absorbance of 0.2 or less of the non-ultraviolet curable pressure-sensitive adhesive layer overlap each other. Since the non-ultraviolet curable pressure-sensitive adhesive layer is transparent to ultraviolet rays, it is possible to irradiate the ultraviolet ray on the ultraviolet curable pressure-sensitive adhesive layer through the non-ultraviolet curable pressure-sensitive adhesive layer.

In the first aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer has a tensile strength at 23° C. of 5.0 N/10 mm or more and 20.0 N/10 mm or less.
In the second aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer preferably has a tensile strength at 23° C. of 5.0 N/10 mm or more and 20.0 N/10 mm or less.
When the tensile strength of the non-ultraviolet curable pressure-sensitive adhesive layer is in the above range, the pressure-sensitive adhesive tape is less likely to be torn during peeling. From the viewpoint of further suppressing tearing of the adhesive tape at the time of peeling, the preferable lower limit of the tensile strength of the non-ultraviolet curable adhesive layer is 5.5 N/10 mm, the more preferable lower limit thereof is 6.0 N/10 mm, and the preferable upper limit thereof is 19.5 N/10 mm, and a more preferable upper limit is 19.0 N/10 mm.
The tensile strength of the non-ultraviolet curable pressure-sensitive adhesive layer was measured using a sample of the non-ultraviolet curable pressure-sensitive adhesive layer cut into a thickness of 200 μm and a width of 10 mm under the conditions of 23° C. and 50% RH. The tensile strength can be measured at a speed of 300 mm/min and a distance between marked lines of 40 mm by using Orientec.

The non-ultraviolet curable pressure-sensitive adhesive layer has an outgas amount of 10,000 ppm or less when the non-ultraviolet curable pressure-sensitive adhesive layer is heated at 260° C. for 15 minutes.
In the production of electronic components involving high-temperature treatment, when a pressure-sensitive adhesive tape having a general non-ultraviolet curable pressure-sensitive adhesive layer and a UV-curable pressure-sensitive adhesive layer is used to protect the electronic components, the heat of the high temperature treatment causes The non-ultraviolet curable pressure-sensitive adhesive layer is decomposed to generate a large amount of outgas. The generated outgas foams the non-ultraviolet curable pressure-sensitive adhesive layer and reduces its strength and adhesive strength.Therefore, at the time of peeling, peeling occurs between the support and the non-ultraviolet curable pressure-sensitive adhesive layer. There is a problem that the adhesive tape remains on the body side (adhesive residue). In the pressure-sensitive adhesive tape of the present invention, the outgassing amount of the non-ultraviolet curable pressure-sensitive adhesive layer is small, that is, the non-ultraviolet curable pressure-sensitive adhesive layer is difficult to decompose by heat, and thus the non-ultraviolet curable pressure-sensitive adhesive layer foams It is possible to prevent the adhesive tape from remaining on the adherend by suppressing From the viewpoint of further suppressing the adhesive residue of the adhesive tape on the adherend, the outgas amount is preferably 7500 ppm or less, more preferably 5500 ppm or less, even more preferably 4000 ppm or less, and 3500 ppm or less. It is particularly preferable that The lower limit of the amount of outgas is not particularly limited, and the lower it is, the more preferable it is. For example, the lower limit is preferably 1000 ppm.

The outgas amount is, for example, by cutting the non-ultraviolet curable pressure-sensitive adhesive layer into a size of 5 mm×5 mm, and performing thermal desorption GC-MS (thermal desorption device: TurboMatrix 350, manufactured by Perkin Elmer Co., GC-MS device: JMS Q1000, Japan. It can be obtained as the amount of gas (ppm in toluene: μg/g) when measured using an electronic device.
The detailed measurement conditions are as follows.
Sample heating conditions: 260° C., 15 min (20 mL/min)
Secondary desorption: 350°C, 40 min
Split: Inlet 25 mL/min, Outlet 25 mL/min
Injection volume: 2.5%
Column: EQUITY-1 (non-polar, SIGMA-ALDRICH) 0.32 mm×60 m×0.25 μm
GC temperature rise: 40° C. (4 min)→temperature rise at a rate of 10° C./min→300° C. (10 min)
He flow rate: 1.5 mL/min
Ionization voltage: 70 eV
MS measurement range: 29 to 600 amu (scan 500 ms)
MS temperature: ion source; 230°C, interface; 250°C

The non-ultraviolet curable pressure-sensitive adhesive layer preferably has a tack strength of 10 to 300 gf/3 mmφ.
When the tack strength of the non-ultraviolet curable pressure-sensitive adhesive layer is in the above range, the non-ultraviolet curable pressure-sensitive adhesive layer is more reliably adhered to the support, and the ultraviolet-curable pressure-sensitive adhesive layer is adhered to the support during peeling. The adhesive tape can be easily peeled off from the interface with the body. From the viewpoint of further facilitating the peeling of the pressure-sensitive adhesive tape from the interface between the ultraviolet-curable pressure-sensitive adhesive layer and the adherend, a more preferable lower limit of the tack strength is 15 gf/3 mmφ, a still more preferable lower limit is 20 gf/3 mmφ, and a more preferable upper limit is 270 gf. /3 mmφ, and a more preferable upper limit is 250 gf/3 mmφ.
The tack strength can be measured by cutting out the non-ultraviolet curable pressure-sensitive adhesive layer into 10 mm×10 mm to prepare a measurement sample, and performing probe tack measurement on the obtained measurement sample. The equipment used and the measurement conditions can be as follows.
Tacking tester: TAC1000, manufactured by RHESCA (or its equivalent)
Probe diameter: 3mmφ
Crimping load: 100g
Crimping time: 1 second Contact speed: 30mm・min
Peeling speed: 600 mm/min

The non-ultraviolet curable pressure-sensitive adhesive layer preferably has a gel fraction of 80% or more.
Since the gel fraction of the non-ultraviolet curable pressure-sensitive adhesive layer is 80% or more, the chemical resistance of the non-ultraviolet curable pressure-sensitive adhesive layer is improved, and therefore the pressure-sensitive adhesive tape of the present invention even in a step involving chemical treatment. Can be used.
From the viewpoint of further improving chemical resistance, the gel fraction is more preferably 95% or more, further preferably 97% or more. The upper limit of the gel fraction is not particularly limited, but is usually 100% or less. The gel fraction can be measured by the following method.
Only 0.1 g of the non-ultraviolet curable pressure-sensitive adhesive layer of the obtained pressure-sensitive adhesive tape was scraped off, immersed in 50 mL of ethyl acetate, and shaken with a shaker at a temperature of 23° C. and 120 rpm for 24 hours (hereinafter, The non-ultraviolet curable pressure-sensitive adhesive layer scraped off is referred to as a pressure-sensitive adhesive composition). After shaking, ethyl acetate and the swelled pressure-sensitive adhesive composition are separated using a metal mesh (opening #200 mesh). The pressure-sensitive adhesive composition after separation is dried at 110° C. for 1 hour. The weight of the pressure-sensitive adhesive composition containing the dried metal mesh is measured, and the gel fraction of the non-ultraviolet curable pressure-sensitive adhesive layer is calculated using the following formula.
Gel fraction (% by weight)=100×(W ₁ −W ₂ )/W ₀
(W ₀ : weight of initial pressure-sensitive adhesive composition, W ₁ : weight of pressure-sensitive adhesive composition containing dried metal mesh, W ₂ : initial weight of metal mesh)

The non-ultraviolet curable pressure-sensitive adhesive constituting the non-ultraviolet curable pressure-sensitive adhesive layer is not particularly limited as long as it is a non-ultraviolet curable type and the tensile strength and the amount of outgas are satisfied, but the base polymer is a functional group capable of reacting with an epoxy group. It is preferable to have a group.
Examples of the functional group capable of reacting with the epoxy group include a carboxyl group, a hydroxyl group, a phenol group, an ester group, an amino group, a carbonyl group, a methoxy group and a sulfo group. Of these, at least one selected from the group consisting of a carboxyl group, a hydroxyl group, a phenol group, an ester group, and an amino group is preferable because it has high reactivity.

Examples of the base polymer include acrylic polymers, silicone polymers, urethane polymers and the like.
In the first aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer comprises, as (A) a base polymer, (a) an alkyl (meth)acrylic acid alkyl ester having 4 to 12 carbon atoms in an amount of 92 to 97% by weight. And (b) a carboxyl group-containing monomer (3.0 to 8.0% by weight) as a constituent, (c) a weight average molecular weight of 700,000 or more (d) a (meth)acryl having a molecular weight distribution of 2 to 6 It is preferable to contain a system copolymer.
In the second aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer comprises 92 to 97% by weight of a (meth)acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group as the (A') base polymer. It contains a (meth)acrylic copolymer that is included as a component. Also in the second aspect of the present invention, the above-mentioned (meth)acrylic copolymer is 92 to 97% by weight of a (meth)acrylic acid alkyl ester having an alkyl group having 4 to 12 carbon atoms and a carboxyl group-containing unit amount. It is preferable that the content of the polymer is 3.0 to 8.0% by weight, the weight average molecular weight is 700,000 or more, and the molecular weight distribution is 2 to 6.

Use of a (meth)acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group as a constituent component to provide a non-ultraviolet curable pressure-sensitive adhesive layer having more excellent adhesive strength (preferably having ultraviolet transparency). You can Further, by using the carboxyl group-containing monomer as a constituent component, it is possible to increase the cohesive force of the non-ultraviolet curable pressure-sensitive adhesive and to impart a larger pressure-sensitive adhesive force. Furthermore, when the above-mentioned UV-curable pressure-sensitive adhesive layer contains a silicone compound, the carboxyl group, which is a polar group, inhibits the approach of a low-polarity silicone compound, so that the silicone compound bleeds out to the non-UV-curable pressure-sensitive adhesive layer side. Can be suppressed.

Examples of the (meth)acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group include butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate and the like. Can be mentioned. Of these, butyl acrylate is preferable because it has excellent adhesive strength.

Examples of the carboxyl group-containing monomer include acrylic acid and methacrylic acid. Of these, acrylic acid is preferred because it can impart high adhesion.

When the content of the (meth)acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group is 92 to 97% by weight, a pressure-sensitive adhesive tape having more excellent adhesive strength can be obtained. When the UV-curable pressure-sensitive adhesive layer contains a silicone compound, the carboxyl group-containing monomer is 3.0% by weight or more, so that the bleed-out of the silicone compound to the non-UV-curable pressure-sensitive adhesive layer is further suppressed. can do. When the content of the carboxyl group-containing monomer is 8.0% by weight or less, the acidity of the (meth)acrylic copolymer can be adjusted to an appropriate range, and the UV-curable pressure-sensitive adhesive layer contains a silicone compound. In this case, bleeding out of the silicone compound to the non-ultraviolet curable pressure-sensitive adhesive layer can be further suppressed.
From the viewpoint of further suppressing bleed-out, the content of the (meth)acrylic acid alkyl ester in the (meth)acrylic copolymer has a more preferred lower limit of 93% by weight, and a still more preferred lower limit of 94% by weight, A more preferable upper limit is 96% by weight. From the viewpoint of further suppressing bleed-out, the content of the carboxyl group-containing monomer in the (meth)acrylic copolymer has a more preferred lower limit of 4.0% by weight and a more preferred upper limit of 7.0% by weight. %, and a more preferable upper limit is 6.0% by weight.

Since the (meth)acrylic copolymer has a large weight average molecular weight of 700,000 or more and a narrow molecular weight distribution of 2 to 6, the tensile strength and the outgas amount of the non-ultraviolet curable pressure-sensitive adhesive layer are within the above ranges. Can be easily adjusted. Here, the molecular weight distribution refers to the ratio (Mw/Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn). The more preferable lower limit of the weight average molecular weight is 750,000, and the further preferable lower limit is 800,000. The upper limit of the weight average molecular weight is not particularly limited, but from the viewpoint of handleability, a preferable upper limit is 1.2 million. The more preferable lower limit of the molecular weight distribution is 2.5, the more preferable lower limit is 3, the more preferable upper limit is 5.5, and the still more preferable upper limit is 5. The weight average molecular weight and the molecular weight distribution can be determined by the GPC measurement method, and specifically, the methods shown in the examples can be used.
Examples of the method for obtaining the (meth)acrylic copolymer having the weight average molecular weight and the molecular weight distribution include solution polymerization, emulsion polymerization, living radical polymerization and the like.

In the first aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer preferably contains (B) an epoxy compound as a curing agent, and preferably contains an epoxy compound having a tertiary amine structure. More preferable.
In the second aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer contains (B) an epoxy compound having a tertiary amine structure as a curing agent.
When the non-ultraviolet curable pressure-sensitive adhesive layer contains an epoxy compound, the base polymer can be crosslinked to improve the chemical resistance and heat resistance of the non-ultraviolet curable pressure-sensitive adhesive layer. In addition, the base polymer after cross-linking has a molecular structure in which the gel fraction is improved and it is difficult to move. Therefore, when the ultraviolet-curable pressure-sensitive adhesive layer contains a silicone compound, it inhibits the bleed-out of the silicone compound to the non-ultraviolet-curable pressure-sensitive adhesive layer, resulting in sufficient adhesive force even when stored for a long time. Can be demonstrated. Examples of the epoxy compounds include N,N,N',N'-tetraglycidyl-1,3-benzenedi(methanamine), methylglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxy. Examples thereof include phthalate, bis-(3,4-epoxycyclohexyl) adipate, bisphenol A diglycidyl ether, diglycidyl ether condensate of bisphenol A, epichlorohydrin modified product of novolac resin and cresol resin. Above all, an epoxy compound having a tertiary amine structure is preferable.

Since the base polymer before the crosslinking reaction with the epoxy compound has a low gel fraction and has a structure in which the molecule moves easily, when the above ultraviolet-curable pressure-sensitive adhesive layer contains a silicone compound, the silicone compound easily bleeds out. .. Therefore, if the rate of the crosslinking reaction is slow, a large amount of the silicone compound may bleed out to the non-ultraviolet curable pressure-sensitive adhesive layer. When a tertiary amino group is present in the non-ultraviolet curable pressure-sensitive adhesive layer, the tertiary amino group acts as a catalyst for the cross-linking reaction, increasing the rate of the cross-linking reaction of the base polymer, so that the reaction is completed early. .. The early completion of the crosslinking reaction makes it difficult for the silicone compound to bleed out into the non-ultraviolet curable pressure-sensitive adhesive layer, so it is possible to obtain a pressure-sensitive adhesive tape with sufficient adhesive strength even when stored for a long period of time. it can. Examples of the epoxy compound having a tertiary amine include N,N,N',N'-tetraglycidyl-1,3-benzenedi(methanamine) and the like.

With respect to the content of the curing agent (the epoxy compound) in the non-ultraviolet curable pressure-sensitive adhesive layer, a preferred lower limit is 0.1 part by weight, and a more preferred lower limit is 0.2 part by weight, relative to 100 parts by weight of the base polymer. A more preferable lower limit is 0.3 part by weight, a preferable upper limit is 0.5 part by weight, a more preferable upper limit is 0.45 part by weight, and a still more preferable upper limit is 0.4 part by weight. When the content of the epoxy compound is within the above range, the base polymer can be crosslinked sufficiently and quickly, and the bleedout of the silicone compound to the non-ultraviolet curable pressure-sensitive adhesive layer can be further suppressed.

In the first aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer preferably contains (C) a filler.
In the second aspect of the present invention, the non-ultraviolet curable pressure-sensitive adhesive layer contains (C) filler.
When the non-ultraviolet curable pressure-sensitive adhesive layer contains a filler, heat resistance can be improved. Examples of the filler include silica filler, aluminum filler, calcium filler, boron filler, magnesium filler, zirconia filler and the like. Among them, silica filler is preferable.

The silica filler is preferably a silica filler oxide because it can further suppress bleed-out of the silicone compound when the ultraviolet-curable pressure-sensitive adhesive layer contains the silicone compound. Since the silica filler oxide has a hydrophilic group and high polarity, inclusion of the silica filler oxide in the non-ultraviolet curable pressure-sensitive adhesive layer can prevent a substance having low polarity from approaching. Therefore, when the ultraviolet curable adhesive layer contains a silicone compound having a low polarity, it is possible to prevent the silicone compound from bleeding out to the non-ultraviolet curable adhesive layer.

The silica filler oxide is not particularly limited, and examples thereof include silicon-aluminum-boron composite oxide, silicon-titanium composite oxide, silica-titania composite oxide, magnesium-aluminum-silicon composite oxide, hexamethylcyclotrisiloxane. , Tetramethoxysilane, chlorosilane, monosilane and the like. Of these, silicon-aluminum-boron composite oxides, silicon-titanium composite oxides, and silica-titania composite oxides are preferable because they have physical properties similar to those of silica generally used as an inorganic filler.

When the silica filler is a silica filler oxide, it is preferable that at least a part of the surface of the silica filler oxide is hydrophobized.
Since at least a part of the hydrophilic groups present in the silica filler oxide is replaced with the hydrophobic group, dispersibility in the base polymer can be improved. The hydrophobic group is not particularly limited, and examples thereof include a methyl group, an ethyl group, a propyl group and a butyl group. Above all, from the viewpoint of dispersibility in the base polymer, it is preferable that the silica filler oxide after the hydrophobic treatment has a monomethylsilyl group, a dimethylsilyl group or a trimethylsilyl group. In particular, at least a part of the silica filler oxide has a monomethylsilyl group because of the excellent balance between the effect of suppressing the bleed-out of the silicone compound to the non-ultraviolet curable pressure-sensitive adhesive layer and the dispersibility in the base polymer. Is more preferable. As described above, since the silica filler oxide prevents the silicone compound from approaching due to its hydrophilicity, the one in which all the surfaces of the silica filler oxide are replaced with a hydrophobic group has an effect as the silica filler oxide. It is difficult to demonstrate.

When the silica filler oxide has a monomethylsilyl group, a dimethylsilyl group or a trimethylsilyl group in at least a part thereof, the silica filler oxide has the functional group in an original specific surface area of 100 m ² /g or more. It is preferable to have 140 m ² /g or more. When the silica filler oxide has the above-mentioned functional group on the surface within the above range, the dispersibility of the silica filler oxide in the base polymer can be further improved.

The average particle size of the filler is not particularly limited, but the preferred lower limit is 0.06 μm, the more preferred lower limit is 0.07 μm, the preferred upper limit is 2 μm, and the more preferred upper limit is 1 μm. When the average particle diameter of the filler is within the above range, the dispersibility in the non-ultraviolet curable pressure-sensitive adhesive can be further improved.

The content of the filler is not particularly limited, but the preferable lower limit is 3 parts by weight and the preferable upper limit is 20 parts by weight with respect to 100 parts by weight of the base polymer.
When the content of the filler is 3 parts by weight or more, the heat resistance of the resulting adhesive tape can be improved. When the content of the silica filler is 20 parts by weight or less, an adhesive tape having sufficient adhesive force can be obtained. From the viewpoint of further improving the heat resistance of the adhesive tape, the content of the silica filler with respect to 100 parts by weight of the base polymer has a more preferred lower limit of 6 parts by weight, a still more preferred lower limit of 8 parts by weight, and a more preferred upper limit of 18 parts by weight. Parts, more preferable upper limit is 15 parts by weight, and particularly preferable upper limit is 13 parts by weight.

The non-ultraviolet curable pressure-sensitive adhesive layer may contain a tackifier.
By containing the tackifier in the ultraviolet-curable pressure-sensitive adhesive layer, the adhesive strength can be further increased. However, since the tackifier may cause outgas during high temperature treatment, it is preferable not to use it or to use it in a small amount. Therefore, when a tackifier is used, the non-ultraviolet curable pressure-sensitive adhesive layer preferably contains 30 parts by weight or less of the tackifier with respect to 100 parts by weight of the (meth)acrylic copolymer. By setting the content of the tackifier in the above range, generation of outgas due to heat can be suppressed and the amount of outgas can be easily adjusted. A more preferable upper limit of the tackifier is 20 parts by weight, and a further preferable upper limit is 10 parts by weight. The lower limit of the tackifier is not particularly limited, but is preferably 0 part by weight from the viewpoint of minimizing the amount of outgas generated, and is 3 parts by weight from the viewpoint of further improving the adhesive strength. preferable.

The non-ultraviolet curable pressure-sensitive adhesive layer may contain known additives such as a plasticizer, a resin, a surfactant, a wax, and a fine particle filler. One or two or more of the above additives may be used.

The thickness of the non-ultraviolet curable pressure-sensitive adhesive layer is not particularly limited, but the preferred lower limit is 5 μm, the more preferred lower limit is 10 μm, the preferred upper limit is 100 μm, and the more preferred upper limit is 60 μm. When the thickness of the non-ultraviolet curable pressure-sensitive adhesive layer is within the above range, the non-ultraviolet curable pressure-sensitive adhesive layer can be adhered to the support with sufficient adhesive force, and the adherend can be reliably fixed.

Examples of the UV-curable pressure-sensitive adhesive component forming the UV-curable pressure-sensitive adhesive layer include a UV-curable pressure-sensitive adhesive containing a polymerizable polymer as a main component and an UV polymerization initiator as a polymerization initiator. As the above-mentioned polymerizable polymer, for example, a (meth)acrylic polymer having a functional group in the molecule (hereinafter, referred to as a functional group-containing (meth)acrylic polymer) is synthesized in advance and reacted with the above-mentioned functional group in the molecule. It can be obtained by reacting a compound having a functional group with a radical-polymerizable unsaturated bond (hereinafter referred to as a functional group-containing unsaturated compound).

The functional group-containing (meth)acrylic polymer has as a main monomer an acrylic acid alkyl ester and/or a methacrylic acid alkyl ester in which the carbon number of the alkyl group is in the range of 2 to 18, and this and a functional group-containing monomer, Further, it is obtained by copolymerizing, if necessary, these with another modifying monomer copolymerizable with them by a conventional method. The weight average molecular weight of the functional group-containing (meth)acrylic polymer is usually about 200,000 to 2,000,000. In the present specification, the weight average molecular weight can be usually determined by the GPC method, and specifically, the method shown in the examples can be used.

Examples of the functional group-containing monomer include a carboxyl group-containing monomer, a hydroxyl group-containing monomer, an epoxy group-containing monomer, an isocyanate group-containing monomer, and an amino group-containing monomer. Examples of the carboxy group-containing monomer include acrylic acid and methacrylic acid. Examples of the hydroxyl group-containing monomer include hydroxyethyl acrylate and hydroxyethyl methacrylate. Examples of the epoxy group-containing monomer include glycidyl acrylate and glycidyl methacrylate. Examples of the isocyanate group-containing monomer include isocyanate ethyl acrylate and isocyanate ethyl methacrylate. Examples of the amino group-containing monomer include aminoethyl acrylate and aminoethyl methacrylate.

Examples of the other copolymerizable modifying monomer include various monomers used for general (meth)acrylic polymers such as vinyl acetate, acrylonitrile, and styrene.

As the functional group-containing unsaturated compound to be reacted with the functional group-containing (meth)acrylic polymer, the same functional group-containing monomer as described above depending on the functional group of the functional group-containing (meth)acrylic polymer is used. it can. For example, when the functional group containing the functional group-containing (meth)acrylic polymer is a carboxyl group, an epoxy group-containing monomer or an isocyanate group-containing monomer is used. When the functional group is a hydroxyl group, an isocyanate group-containing monomer is used. When the functional group is an epoxy group, a carboxyl group-containing monomer or an amide group-containing monomer such as acrylamide is used. When the functional group is an amino group, an epoxy group-containing monomer is used.

Examples of the ultraviolet polymerization initiator include those activated by irradiation with ultraviolet rays having a wavelength of 200 to 410 nm. Examples of such ultraviolet polymerization initiators include acetophenone derivative compounds, benzoin ether compounds, ketal derivative compounds, phosphine oxide derivative compounds, bis(η5-cyclopentadienyl)titanocene derivative compounds, benzophenone, Michler's ketone, chlorothioxanthone. , Todecyl thioxanthone, dimethyl thioxanthone, diethyl thioxanthone, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethyl phenyl propane and the like. Examples of the acetophenone derivative compound include methoxyacetophenone. Examples of the benzoin ether compound include benzoin propyl ether and benzoin isobutyl ether. Examples of the ketal derivative compound include benzyl dimethyl ketal and acetophenone diethyl ketal. These UV polymerization initiators may be used alone or in combination of two or more kinds.

The ultraviolet-curable pressure-sensitive adhesive layer preferably contains a radically polymerizable polyfunctional oligomer or monomer. By containing the radical-polymerizable polyfunctional oligomer or monomer in the UV-curable pressure-sensitive adhesive layer, the UV-curability is improved.
The polyfunctional oligomer or monomer preferably has a weight average molecular weight of 10,000 or less, more preferably the weight average molecular weight thereof so that three-dimensional reticulation of the UV-curable pressure-sensitive adhesive layer by irradiation with UV rays can be efficiently performed. It has a molecular weight of 5,000 or less and the number of radical-polymerizable unsaturated bonds in the molecule is 2 to 20. The weight average molecular weight can be determined by using, for example, a GPC measuring method, and specifically, the method shown in Examples can be used.

The polyfunctional oligomer or monomer is, for example, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or a methacrylate similar to the above. And the like. Other examples include 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate, and the same methacrylates as described above. These polyfunctional oligomers or monomers may be used alone or in combination of two or more.

The UV-curable pressure-sensitive adhesive layer preferably contains a silicone compound.
When the UV-curable pressure-sensitive adhesive layer contains a silicone compound, the silicone compound bleeds out at the interface between the UV-curable pressure-sensitive adhesive layer and the adherend, so that the pressure-sensitive adhesive tape can be easily peeled off after the treatment. it can. In addition, since the silicone compound has excellent heat resistance, it is possible to suppress sticking of the UV-curable pressure-sensitive adhesive layer and suppress adhesive residue even when a treatment involving heating at 150° C. or higher is performed.

The silicone compound preferably has a functional group capable of crosslinking with the ultraviolet-curable pressure-sensitive adhesive component.
Since the silicone compound has a functional group that can be crosslinked with the UV-curable pressure-sensitive adhesive component, the silicone compound is chemically reacted with the UV-curable pressure-sensitive adhesive component by UV irradiation and is incorporated into the UV-curable pressure-sensitive adhesive component, Contamination due to the adhesion of the silicone compound to the adherend is suppressed. The functionality of the silicone compound is, for example, 2 to 6, preferably 2 to 4, and more preferably divalent. The functional group is appropriately determined depending on the functional group contained in the UV-curable pressure-sensitive adhesive component. For example, the UV-curable pressure-sensitive adhesive component is a photocurable resin mainly containing a (meth)acrylic acid alkyl ester-based polymerizable polymer. In the case of a pressure-sensitive adhesive, a functional group capable of crosslinking with a (meth)acrylic group is selected.
The functional group capable of crosslinking with the (meth)acrylic group is a functional group having an unsaturated double bond, and specifically contains, for example, a vinyl group, a (meth)acrylic group, an allyl group, a maleimide group, or the like. Select a silicone compound.

The silicone compound preferably has a weight average molecular weight of 300 to 50,000.
When the weight average molecular weight of the silicone compound is 300 or more, bleed-out to the non-ultraviolet curable pressure-sensitive adhesive layer can be further suppressed depending on the molecular size. When the weight average molecular weight is 50,000 or less, bleed-out can be caused at the interface between the ultraviolet-curable pressure-sensitive adhesive layer and the adherend to further suppress the promotion of adhesion. The more preferable lower limit of the weight average molecular weight of the silicone compound is 400, the still more preferable lower limit is 500, the more preferable upper limit is 10,000, and the still more preferable upper limit is 5000. In the present invention, the weight average molecular weight of the silicone compound can be determined by GPC analysis, and specifically, the method shown in Examples can be used.

Examples of the silicone compound having the functional group and the weight average molecular weight include silicon diacrylate. When silicon diacrylate is used, heat resistance and peelability are further improved.

The content of the silicone compound is preferably such that the lower limit is 1 part by weight, the upper limit is 50 parts by weight, the more preferable lower limit is 10 parts by weight, and the more preferable upper limit is 40 parts by weight with respect to 100 parts by weight of the polymerizable polymer. When the content of the silicone compound is within the above range, the adherend can be protected with sufficient adhesive force, and the adhesive tape can be peeled off more easily after the protection is completed.

The UV-curable pressure-sensitive adhesive layer may contain known additives such as an inorganic filler such as fumed silica, a plasticizer, a resin, a surfactant, a wax, and a fine particle filler.

The thickness of the UV-curable pressure-sensitive adhesive layer is not particularly limited, but the lower limit is preferably 5 μm and the upper limit is 100 μm. When the thickness of the UV-curable pressure-sensitive adhesive layer is in the above range, the adherend can be protected with sufficient adhesive force, and the adhesive residue at the time of peeling can be suppressed. From the viewpoint of further improving the adhesive strength and further suppressing the adhesive residue at the time of peeling, the more preferable lower limit of the thickness of the ultraviolet-curable pressure-sensitive adhesive layer is 10 μm, and the more preferable upper limit thereof is 60 μm.

The adhesive tape of the present invention is preferably a non-support type double-sided adhesive tape having no base material. In the case of the support type having a base material, the silicone compound does not bleed out to the interface on the support side, but the cost is inferior to the non-support type because a heat resistant base material must be used. ..

The pressure-sensitive adhesive tape of the present invention has a release film (preferably UV-permeable) laminated on the surface of the non-UV curable adhesive layer opposite to the surface on which the UV curable adhesive layer is laminated. Is preferred.
By providing the release film on the non-ultraviolet curable pressure-sensitive adhesive layer, the non-ultraviolet curable pressure-sensitive adhesive layer can be protected until it is attached to an adherend and the handleability of the pressure-sensitive adhesive tape can be improved. In addition, when the release film is UV transparent, the curing step described below can be performed while the non-UV curable pressure-sensitive adhesive layer is protected.

The release film is not particularly limited, and examples thereof include polyethylene naphthalate (PEN), polyimide (PI), polyether ether ketone (PEEK), polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT). ), polyhexamethylene terephthalate, polybutylene naphthalate, butanediol polytetramethylene glycol terephthalate copolymer, butanediol terephthalate polycaprolactone copolymer, and other UV transparent films. Among them, polyethylene terephthalate (PET) is preferable.

The pressure-sensitive adhesive tape of the present invention has a UV-curable pressure-sensitive adhesive layer and a non-UV-curable pressure-sensitive adhesive layer as long as the UV-curable pressure-sensitive adhesive layer and the non-UV-curable pressure-sensitive adhesive layer are located at the outermost layers (layers in contact with the adherend). You may have another layer between the adhesive layers.

The adhesive tape of the present invention preferably has a tensile strength at 23° C. before curing of 2.5 to 10 N/10 mm.
When the tensile strength of the pressure-sensitive adhesive tape before curing is within the above range, the pressure-sensitive adhesive tape can be less likely to be torn during peeling. From the viewpoint of further suppressing tearing of the pressure-sensitive adhesive tape at the time of peeling, a more preferable lower limit of the tensile strength before curing of the pressure-sensitive adhesive tape is 3.0 N/10 mm, a still more preferable lower limit is 3.5 N/10 mm, and a more preferable upper limit is The upper limit is 9.5 N/10 mm, and the more preferable upper limit is 9.0 N/10 mm. The tensile strength of the adhesive tape before curing can be measured by the same method as the tensile strength of the non-ultraviolet curable adhesive layer.

In the pressure-sensitive adhesive tape of the present invention, it is preferable that the gel fraction of the UV-curable pressure-sensitive adhesive layer is 80% or more after UV-curing.
When the gel fraction of the UV-curable pressure-sensitive adhesive layer is at least the above lower limit, the chemical resistance of the pressure-sensitive adhesive tape can be further improved, and at the same time, bleeding of the silicone compound into the non-UV-curable pressure-sensitive adhesive layer over time. Out can be suppressed more. A more preferred lower limit of the gel fraction of the ultraviolet-curable pressure-sensitive adhesive layer is 85%, and a still more preferred lower limit thereof is 90%. The upper limit of the gel fraction of the UV-curable pressure-sensitive adhesive layer is not particularly limited, but is preferably 99%. When the pressure-sensitive adhesive tape has a layer other than the UV-curable pressure-sensitive adhesive layer and the non-UV-curable pressure-sensitive adhesive layer, it is preferable that the layer also satisfy the gel fraction.

The method for producing the pressure-sensitive adhesive tape of the present invention is not particularly limited, and a conventionally known method can be used. For example, a solution of the UV-curable pressure-sensitive adhesive component is applied onto a release-treated film and dried to form a UV-curable pressure-sensitive adhesive layer, and the same release-treated film is formed on the film. After the non-ultraviolet curable pressure-sensitive adhesive layer is formed by the method, the ultraviolet curable pressure-sensitive adhesive layer and the non-ultraviolet curable pressure-sensitive adhesive layer can be attached to each other to manufacture.

The application of the pressure-sensitive adhesive tape of the present invention is not particularly limited, but it is particularly preferably used as a protective tape in the production of electronic components such as an electronic substrate and a semiconductor chip, which uses an opaque support and has a production process involving high-temperature treatment. it can.
As a method of manufacturing such an electronic component, for example, the following method of manufacturing an electronic component may be mentioned. That is, an adherend adhering step of adhering the ultraviolet curable adhesive layer to an adherend, a curing step of irradiating ultraviolet rays to cure the ultraviolet curable adhesive layer, and the non-ultraviolet curable adhesive layer It is a method including a support sticking step of sticking a support thereon, a heat treatment step of treating the adherend at a high temperature of 150° C. or higher, and a peeling step of peeling the adherend from the adhesive tape. In such a method of manufacturing an electronic component, the effects of the present invention can be exhibited particularly advantageously.

The pressure-sensitive adhesive tape of the present invention, an adherend sticking step of sticking the ultraviolet-curable pressure-sensitive adhesive layer to an adherend, a curing step of irradiating ultraviolet rays to cure the ultraviolet-curable pressure-sensitive adhesive layer, and the non-ultraviolet curing A support sticking step of sticking a support on the mold pressure-sensitive adhesive layer, a heat treatment step of treating the adherend at a high temperature of 150° C. or higher, and a peeling step of peeling the adherend from the adhesive tape, A method of manufacturing an electronic component is also one aspect of the present invention.

In the method for producing an electronic component of the present invention, first, the pressure-sensitive adhesive tape of the present invention having a UV-curable pressure-sensitive adhesive layer and a non-UV-curable pressure-sensitive adhesive layer is applied to the adherend from the UV-curable pressure-sensitive adhesive layer. Perform the sticking process.
Examples of the adherend include a silicon wafer, a semiconductor chip, a base material that is a base for manufacturing an electronic substrate, a material for an electronic component, and the like. Examples of the base material include a polyimide film and a glass epoxy substrate.

In the method of manufacturing an electronic component of the present invention, a curing step of irradiating ultraviolet rays to cure the ultraviolet curable pressure-sensitive adhesive layer is then performed.
By curing the ultraviolet-curable pressure-sensitive adhesive layer, the pressure-sensitive adhesive tape can be easily peeled off from the adherend after the treatment while suppressing the adhesive residue. In the method for manufacturing an electronic component of the present invention, since the ultraviolet curable adhesive layer is cured before the adhesive tape is attached to the support, the ultraviolet curable adhesive layer is formed even if the support does not transmit light. Can be cured. When the non-ultraviolet curable adhesive layer of the pressure-sensitive adhesive tape is ultraviolet-transparent, the non-ultraviolet curable adhesive layer is sufficiently irradiated with ultraviolet rays from the non-ultraviolet curable adhesive layer side. Can be cured. Since the UV-curable pressure-sensitive adhesive layer is cured after being attached to the adherend, even if the UV-curable pressure-sensitive adhesive layer is cured before the treatment of the adherend, the adhesion is The tape does not immediately peel from the adherend.

The irradiation conditions of light for curing the ultraviolet curable pressure-sensitive adhesive layer can be appropriately adjusted depending on the combination of the polymerizable polymer used and the ultraviolet polymerization initiator. For example, when using a polymerizable polymer having an unsaturated double bond such as a vinyl group in the side chain and an ultraviolet polymerization initiator that is activated at a wavelength of 200 to 410 nm, by irradiating with light having a wavelength of 365 nm or more, The ultraviolet curable pressure-sensitive adhesive layer can be crosslinked and cured.
Such an ultraviolet curable pressure-sensitive adhesive layer is preferably irradiated with light having a wavelength of 365 nm with an illuminance of 5 mW or more, more preferably with an illuminance of 10 mW or more, and with an illuminance of 20 mW or more. Is more preferable, and irradiation with an illuminance of 50 mW or higher is particularly preferable. In addition, it is preferable to irradiate light having a wavelength of 365 nm with an integrated illuminance of 300 mJ or more, more preferably 500 mJ or more and 10000 mJ or less, and further preferably 500 mJ or more and 7500 mJ or less. It is particularly preferable to irradiate with an integrated illuminance of 1000 mJ or more and 5000 mJ or less.

In the method of manufacturing an electronic component of the present invention, a support sticking step of sticking a support on the non-ultraviolet curable pressure-sensitive adhesive layer is then performed.
In the method for producing an electronic component of the present invention, since the adhesive layer of the adhesive tape is divided into the ultraviolet-curable adhesive layer and the non-ultraviolet-curable adhesive layer, it is possible to perform the curing step before the support is attached. Even if there is, the non-ultraviolet curable pressure-sensitive adhesive layer does not cure. Therefore, the adhesive tape can be attached to the support with sufficient adhesive force. When the adhesive tape has the ultraviolet-transparent release film, the release film is peeled off after the curing step and before the support attaching step.

In the method of manufacturing an electronic component of the present invention, next, a heat treatment step of treating the adherend at a high temperature of 150° C. or higher is performed.
Examples of the heat treatment process include a substrate manufacturing process and a chip mounting process. In the substrate manufacturing process, heat treatment is usually performed at 150° C. or higher, and in the chip mounting process, heat treatment is normally performed at 200° C. or higher. In the method of manufacturing an electronic component of the present invention, since the UV-curable pressure-sensitive adhesive layer is cured before the heat treatment step, adhesion promotion is suppressed even when a treatment involving a high temperature of 150° C. or higher is performed in the heat treatment step. Therefore, the adherend can be easily peeled off after the treatment. Further, since the ultraviolet-curable pressure-sensitive adhesive layer contains a silicone compound, it is possible to further suppress the promotion of adhesion.

The method for manufacturing an electronic component of the present invention then includes a peeling step of peeling the adherend from the adhesive tape. Since the UV-curable pressure-sensitive adhesive layer is cross-linked and cured in the curing step, the adherend can be easily peeled from the pressure-sensitive adhesive tape while suppressing the adhesive residue. Further, the non-ultraviolet curable pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape has an outgas amount of 10,000 ppm or less, so that the non-ultraviolet curable pressure-sensitive adhesive layer is less likely to be foamed by the outgas in the heat treatment step. As a result, the pressure-sensitive adhesive tape is less likely to peel off between the support and the non-ultraviolet curable pressure-sensitive adhesive layer, so that it is possible to prevent the pressure-sensitive adhesive tape from remaining on the adherend side during peeling. Further, since the tensile strength of the non-ultraviolet curable pressure-sensitive adhesive layer is within a certain range, it is difficult for the pressure-sensitive adhesive tape to be torn during peeling.

INDUSTRIAL APPLICABILITY According to the present invention, it can be used for a support that does not transmit light in the production of electronic components, and it is possible to suppress peeling and adhesive residue from the adherend and the support even when high-temperature treatment is performed. It is possible to provide a pressure-sensitive adhesive tape that can be used and a method for manufacturing an electronic component using the pressure-sensitive adhesive tape.

Hereinafter, the embodiments of the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Example 1)
(Production of non-ultraviolet curing adhesive)
To a reactor equipped with a thermometer, a stirrer, and a cooling pipe, 97 parts by weight of butyl acrylate as an alkyl (meth)acrylic acid ester, 3 parts by weight of acrylic acid as a carboxyl group-containing monomer and 120 parts by weight of ethyl acetate were added, and nitrogen substitution was performed. After that, the reactor was heated to start reflux. Then, 0.1 part by weight of azobisisobutyronitrile was added as a polymerization initiator into the reactor. The solution was refluxed at 70° C. for 5 hours to obtain a solution of a (meth)acrylic copolymer (base polymer). With respect to the obtained (meth)acrylic copolymer, the weight average molecular weight and the molecular weight distribution in terms of polystyrene were measured by the GPC method, and were 1,000,000 and 3, respectively. The measuring equipment and measuring conditions were as follows.
Measuring device: 2690 Separations Model, Waters column: GPC KF-806L, Showa Denko detector: Differential refractometer Sample flow rate: 1 mL/min
Column temperature: 40°C
Eluent: ethyl acetate

Then, with respect to 100 parts by weight of the solid content of the (meth)acrylic copolymer contained in the solution of the obtained (meth)acrylic copolymer, 0.35 parts by weight of the epoxy curing agent in terms of solid content is used. Then, 10 parts by weight of silica filler was added and stirred to obtain an ethyl acetate solution of a non-ultraviolet curable adhesive. The epoxy curing agent and silica filler used were as follows.
Epoxy curing agent: Mitsubishi Gas Chemical Co., Ltd., TETRAD-X, tertiary amino group-containing epoxy curing agent Silica filler: Tokuyama Corporation, Reorosil MT-10

(Production of UV-curable adhesive)
A reactor equipped with a thermometer, a stirrer, and a cooling pipe was prepared, and in this reactor, 94 parts by weight of 2-ethylhexyl acrylate as alkyl (meth)acrylate and 6 parts by weight of hydroxyethyl methacrylate as a functional group-containing monomer. After adding 0.01 part by weight of lauryl mercaptan and 80 parts by weight of ethyl acetate, the reactor was heated to start reflux. Subsequently, 0.01 parts by weight of 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane was added as a polymerization initiator into the reactor, and the polymerization was started under reflux. It was Next, 1 hour and 2 hours after the initiation of the polymerization, 0.01 parts by weight of 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane was added to each of them to further initiate the initiation of the polymerization. After 4 hours, 0.05 part by weight of t-hexyl peroxypivalate was added to continue the polymerization reaction. Then, 8 hours after the initiation of the polymerization, an ethyl acetate solution of a functional group-containing (meth)acrylic polymer having a solid content of 55% by weight and a weight average molecular weight of 600,000 was obtained.
The reaction was carried out by adding 3.5 parts by weight of 2-isocyanatoethyl methacrylate as a functional group-containing unsaturated compound to 100 parts by weight of the resin solid content of the ethyl acetate solution containing the obtained (meth)acrylic polymer containing a functional group. Then, a polymerizable polymer was obtained. Then, 20 parts by weight of silicon diacrylate as a silicone compound, 3 parts by weight of silica filler, 30 parts by weight of urethane acrylate, and isocyanate-based cross-linking agent were added to 100 parts by weight of the resin solid content of the ethyl acetate solution of the obtained polymerizable polymer. 0.7 parts by weight and 1 part by weight of a photopolymerization initiator were mixed to obtain an ethyl acetate solution of a UV-curable adhesive. The following were used as the silicon diacrylate, silica filler, urethane acrylate, isocyanate cross-linking agent, and photopolymerization initiator.
Silicone diacrylate: EBECRYL 350, manufactured by Daicel Ornex Co., weight average molecular weight 1000.
Silica filler: Reorosil MT-10, Tokuyama urethane acrylate: UN-5500, Negami Kogyo Co., Ltd. isocyanate crosslinking agent: Coronate L, Nippon Urethane Co., Ltd. photopolymerization initiator: Esacure One, Japan Siber Hegner

(Manufacture of adhesive tape)
The obtained UV-curable adhesive solution was coated on a 50 μm polyethylene terephthalate (PET) film having a release treatment on one side with a doctor knife so that the dry film thickness was 40 μm, and the temperature was 110° C. The coating solution was dried by heating for 5 minutes to obtain an ultraviolet curable pressure-sensitive adhesive layer.
The resulting non-ultraviolet curable pressure sensitive adhesive solution was coated on a transparent PET film having a thickness of 50 μm on one surface with a doctor knife so that the thickness of the dry film was 40 μm, and the temperature was 110° C. The coating solution was dried by heating for 5 minutes to obtain a non-ultraviolet curable pressure-sensitive adhesive layer.
The surfaces of the obtained ultraviolet-curable pressure-sensitive adhesive layer and non-ultraviolet-curable pressure-sensitive adhesive layer on which the PET films were not laminated were bonded together to obtain a pressure-sensitive adhesive tape.

(Measurement of tensile strength)
An adhesive tape consisting only of the non-ultraviolet curable adhesive layer was produced by the above method. The obtained non-ultraviolet curable pressure-sensitive adhesive layer cut into a thickness of 200 μm and a width of 10 mm is used as a sample, and at a temperature of 23° C. and 50% RH, Tensilon UCE500 (manufactured by Orientec Co., Ltd.) is used, and the speed is 300 mm/min. The tensile strength was measured at a distance between marked lines of 40 mm. In the same manner, the tensile strength before curing of the obtained adhesive tape was measured.

(Measurement of outgas amount)
A pressure-sensitive adhesive tape consisting only of the non-ultraviolet curable pressure-sensitive adhesive layer was prepared by the above method, and the obtained pressure-sensitive adhesive tape consisting only of the non-ultraviolet curable pressure-sensitive adhesive layer was cut into 5 mm×5 mm to prepare a measurement sample. The obtained measurement sample was measured by thermal desorption GC-MS, and the obtained gas amount (ppm in toluene: μg/g) was taken as the outgas amount. The instruments and measurement conditions used are as follows.
Thermal desorption device: TurboMatrix 350, Perkin Elmer
GC-MS device: JMS Q1000, JEOL sample heating conditions: 260° C., 15 min (20 mL/min)
Secondary desorption: 350°C, 40 min
Split: Inlet 25 mL/min, Outlet 25 mL/min
Injection volume: 2.5%
Column: EQUITY-1 (non-polar, SIGMA-ALDRICH) 0.32 mm×60 m×0.25 μm
GC temperature rise: 40° C. (4 min)→temperature rise at a rate of 10° C./min→300° C. (10 min)
He flow rate: 1.5 mL/min
Ionization voltage: 70 eV
MS measurement range: 29 to 600 amu (scan 500 ms)
MS temperature: ion source; 230°C, interface; 250°C

(Measurement of tack strength)
By the above method, an adhesive tape consisting of only the non-ultraviolet curable adhesive layer was prepared as a measurement sample. The obtained adhesive tape consisting only of the non-ultraviolet curable adhesive layer was cut into 10 mm×10 mm to prepare a measurement sample. The probe tack measurement was performed on the obtained measurement sample. The instruments and measurement conditions used are as follows.
Tacking tester: TAC1000, RHESCA probe diameter: 3 mmφ
Crimping load: 100g
Crimping time: 1 second Contact speed: 30mm・min
Peeling speed: 600 mm/min

(Measurement of gel fraction)
Only 0.1 g of the non-ultraviolet curable pressure-sensitive adhesive layer of the obtained pressure-sensitive adhesive tape was scraped off, immersed in 50 ml of ethyl acetate, and shaken with a shaker at a temperature of 23° C. and 120 rpm for 24 hours (hereinafter, The non-ultraviolet curable pressure-sensitive adhesive layer scraped off is referred to as a pressure-sensitive adhesive composition). After shaking, ethyl acetate and the swelled pressure-sensitive adhesive composition were separated using a metal mesh (opening #200 mesh). The pressure-sensitive adhesive composition after separation was dried for 1 hour under the condition of 110°C. The weight of the pressure-sensitive adhesive composition containing the dried metal mesh was measured, and the gel fraction of the non-ultraviolet curable pressure-sensitive adhesive layer was calculated using the following formula. The results are shown in Tables 1 and 2.
Gel fraction (% by weight)=100×(W ₁ −W ₂ )/W ₀
(W ₀ : weight of initial pressure-sensitive adhesive composition, W ₁ : weight of pressure-sensitive adhesive composition containing dried metal mesh, W ₂ : initial weight of metal mesh)

(Examples 2 to 11, Comparative Examples 1 to 11)
The blending amounts of butyl acrylate, acrylic acid and silica filler of the non-ultraviolet curable pressure-sensitive adhesive layer are as shown in Tables 1 and 2, and the weight average molecular weight and the molecular weight distribution of the base polymer are shown in Tables 1 and 2 by changing the polymerization conditions. As described above, a pressure-sensitive adhesive tape was manufactured in the same manner as in Example 1 except that the tackifiers were added in the amounts shown in Tables 1 and 2, and each physical property was measured. As the tackifier, UN5500 manufactured by Negami Kogyo Co., Ltd. was used. Coronate L manufactured by Tosoh Corporation was used as the isocyanate-based curing agent.

<Evaluation>
The adhesive tapes obtained in Examples and Comparative Examples were evaluated by the following methods. The results are shown in Tables 1 and 2.

(1) Evaluation of Heat-treated Adhesive Tape on Substrate The surface of the adhesive tape on the UV-curable adhesive layer side was attached to a substrate (TPWB-S02-READCUT, manufactured by Daisho Denshi KK) to obtain a laminate. Then, using a high-pressure mercury UV irradiator, the illuminance of 365 nm UV is adjusted so that the irradiation intensity on the adhesive tape surface is 100 mW/cm ^2, and the non-ultraviolet curable adhesive layer side is irradiated for 30 seconds. The UV-curable pressure-sensitive adhesive layer was crosslinked and cured. Then, the non-ultraviolet curable pressure-sensitive adhesive layer of the laminate was attached to the CCL support (copper-clad laminate), and heat treatment at 260° C. for 6 minutes was performed three times in total. After the heat treatment was completed, the adhesive tape was peeled off from the substrate. The peeling of the adhesive tape, the foaming of the non-ultraviolet curable adhesive layer, and the adhesive residue on the substrate were evaluated as follows.

(Evaluation of peeling of adhesive tape)
Visually observe the adhesive tape after the heat treatment, "○" when there is no peeling or voids at the interface between the UV-curable adhesive layer and the substrate, "△" when there is some peeling or voids The peeling of the adhesive tape was evaluated as "x" when peeling or voids were present on the entire surface.

(Evaluation of foaming of non-ultraviolet curable adhesive layer)
Visually observe the non-ultraviolet curable pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape after the heat treatment, and when there is no foaming, "◎", when there is almost no foaming, "○", when there is some foaming The foaming of the non-ultraviolet curable pressure-sensitive adhesive layer was evaluated as “Δ” and “x” when there was foaming on the entire surface.

(Evaluation of adhesive residue on the board)
Observe the substrate after peeling with an optical microscope. When there is no adhesive residue, it is "○", when there is almost no adhesive residue, it is "○", when there is some adhesive residue, it is "△", and adhesive is When the remainder was on the entire surface, the adhesive residue on the substrate was evaluated as "x".

(2) Evaluation of chemical resistance A polyimide film was attached to the UV-curable adhesive layer of the obtained adhesive tape, and a CCL plate (copper-clad laminate) was attached to the non-UV-curable adhesive layer to obtain a measurement sample. It was made. The obtained measurement sample was immersed in Pine Alpha (manufactured by Arakawa Chemical Industry Co., Ltd.) at 70° C. for 2 hours and dried in an oven at 110° C. for 1 hour. The weight loss rate before and after immersion was measured.
When the weight reduction rate before and after the immersion was 3.0% or less, it was "A", when it was more than 3.0% and 5.0% or less, it was "O", and it was more than 5.0% and 8.0. The chemical resistance was evaluated as “Δ” when the content was less than %, greater than 8.0%, and as “x” when the tape was peeled from the adherend.

INDUSTRIAL APPLICABILITY According to the present invention, it can be used for a support that does not transmit light in the production of electronic components, and it is possible to suppress peeling and adhesive residue from the adherend and the support even when high-temperature treatment is performed. It is possible to provide a pressure-sensitive adhesive tape that can be used and a method for manufacturing an electronic component using the pressure-sensitive adhesive tape.

Claims (10)

1. A pressure-sensitive adhesive tape having a non-ultraviolet curable pressure-sensitive adhesive layer and an ultraviolet-curable pressure-sensitive adhesive layer laminated on the non-ultraviolet curable pressure-sensitive adhesive layer,
   The non-ultraviolet curable pressure-sensitive adhesive layer has a tensile strength at 23° C. of 5.0 N/10 mm or more and 20.0 N/10 mm or less, and
   An adhesive tape having an outgas amount of 10,000 ppm or less when the non-ultraviolet curable adhesive layer is heated at 260° C. for 15 minutes.
2. The pressure-sensitive adhesive tape according to claim 1, wherein the tack strength of the non-ultraviolet curable pressure-sensitive adhesive layer is 10 to 300 gf/3 mmφ.
3. The non-ultraviolet curable adhesive layer,
   (A) As the base polymer, (a) 92 to 97% by weight of a (meth)acrylic acid alkyl ester having an alkyl group with 4 to 12 carbon atoms, and (b) a carboxyl group-containing monomer 3.0 to 8.0% by weight. % As a constituent component, (c) a weight average molecular weight of 700,000 or more, (d) a (meth)acrylic copolymer having a molecular weight distribution of 2 to 6,
   (B) an epoxy compound containing a tertiary amine structure as a curing agent,
   (C) contains a filler,
   The pressure-sensitive adhesive tape according to claim 1 or 2, which contains 0.1 to 0.5 parts by weight of the curing agent and 3 to 20 parts by weight of the filler with respect to 100 parts by weight of the base polymer.
4. The pressure-sensitive adhesive tape according to claim 1, 2 or 3, wherein the non-ultraviolet curable pressure-sensitive adhesive layer contains 30 parts by weight or less of a tackifier with respect to 100 parts by weight of the (meth)acrylic copolymer.
5. 2. The ultraviolet-curable pressure-sensitive adhesive layer contains an ultraviolet-curable pressure-sensitive adhesive component, and a silicone compound having a functional group capable of crosslinking with the ultraviolet-curable pressure-sensitive adhesive component and having a weight average molecular weight of 300 to 50,000. The adhesive tape according to 2, 3, or 4.
6. The adhesive tape according to claim 1, wherein the gel fraction of the non-ultraviolet curable adhesive layer is 80% or more.
7. The pressure-sensitive adhesive tape according to claim 1, 2, 3, 4, 5, or 6, which has a tensile strength at 23° C. before curing of 2.5 to 10 N/10 mm.
8. A pressure-sensitive adhesive tape having a non-ultraviolet curable pressure-sensitive adhesive layer and an ultraviolet-curable pressure-sensitive adhesive layer laminated on the non-ultraviolet curable pressure-sensitive adhesive layer,
   The amount of outgas when the non-ultraviolet curable pressure-sensitive adhesive layer is heated at 260° C. for 15 minutes is 10,000 ppm or less, and
   The non-ultraviolet curable adhesive layer,
   (A′) a (meth)acrylic copolymer containing 92 to 97% by weight of a (meth)acrylic acid alkyl ester having a carbon number of an alkyl group of 4 to 12 as a base polymer,
   (B) an epoxy compound containing a tertiary amine structure as a curing agent,
   (C) An adhesive tape containing a filler.
9. An adherend adhering step of adhering to the adherend from the ultraviolet curable pressure-sensitive adhesive layer,
   A curing step of irradiating ultraviolet rays to cure the ultraviolet curable pressure-sensitive adhesive layer;
   A support sticking step of sticking a support on the non-ultraviolet curable pressure-sensitive adhesive layer,
   A heat treatment step of treating the adherend at a high temperature of 150° C. or higher;
   The adhesive tape according to claim 1, 2, 3, 4, 5, 6, 7 or 8, which is used in a method for manufacturing an electronic component, including a peeling step of peeling the adherend from the adhesive tape.
10. An adherend attaching step of attaching the adhesive tape according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9 to the adherend from the ultraviolet curable adhesive layer;
    A curing step of irradiating ultraviolet rays to cure the ultraviolet curable pressure-sensitive adhesive layer;
    A support sticking step of sticking a support on the non-ultraviolet curable pressure-sensitive adhesive layer,
    A heat treatment step of treating the adherend at a high temperature of 150° C. or higher;
    And a peeling step of peeling the adherend from the adhesive tape.