Adhesive film, temporary fixing material, cured product, laminate, and method of producing electronic component

Abstract

The present invention provides an adhesive film that allows for efficient removal of a support body even when irradiated with low-energy laser light, and also has excellent adherend removability even when high-temperature processing is performed. The present invention is also able to provide a cured product of the adhesive film. The present invention furthermore provides a laminate comprising a support body, the adhesive film, and a semiconductor, in the stated order. In addition, the present invention provides a method of producing an electronic component using the laminate and comprising a step that allows for efficient removal of a support body even when irradiated with low-energy laser light, and a step making it easy to remove an adherend even when high-temperature processing is performed. The present invention also provides a temporary fixing material that has excellent anti-laser processing performance and allows for efficient removal of a support body even when irradiated with low-energy laser light after curing. The present invention additionally provides a cured product of the temporary fixing material. The present invention furthermore provides a laminate comprising the cured product. In addition, the present invention provides a method of producing an electronic component including a step that allows for efficient removal of a support body even when irradiated with low-energy laser light. The present invention is an adhesive film comprising an adhesive layer containing a curable adhesive, wherein: the curable adhesive is a photocurable adhesive; the adhesive layer, after being irradiated with light in the wavelength 405 nm so as to reach a cumulative light intensity of 20000 mJ / cm2, has a gel fraction of 65 mass% or higher, and the adhesive layer, after being irradiated with light in the wavelength 405 nm so as to reach a cumulative light intensity of 20000 mJ / cm2, has an extinction coefficient, to light in the wavelength 308 nm, of 1.0 × 10-4 or higher.

Description

Adhesive film, temporary fixing material, cured product, laminate, and method for manufacturing electronic component

[0001] The present invention relates to an adhesive film. The present invention also relates to a cured product of the adhesive film. The present invention also relates to a laminate having the adhesive film. The present invention also relates to a method for producing an electronic component using the laminate. The present invention also relates to a temporary fixing material. The present invention also relates to a cured product of the temporary fixing material. The present invention also relates to a laminate having the cured product. The present invention also relates to a method for producing an electronic component.

[0002] During processing of electronic components such as semiconductors, in order to facilitate handling of the electronic components and prevent breakage, the electronic components are temporarily fixed by adhering them to a support via a pressure-sensitive adhesive composition or a temporary fixing material made of the pressure-sensitive adhesive composition, or an adhesive film such as a tape-shaped temporary fixing material having a pressure-sensitive adhesive layer or a pressure-sensitive adhesive film is attached to the electronic components for protection. For example, when a thick-film wafer cut from a high-purity silicon single crystal or the like is ground to a predetermined thickness to obtain a thin-film wafer, the thick-film wafer is adhered to a support via a pressure-sensitive adhesive composition or a temporary fixing material.

[0003] Thus, pressure-sensitive adhesive compositions and pressure-sensitive adhesive films used for electronic components, and temporary fixing materials used for temporarily fixing electronic components, are required to have high enough adhesion to firmly fix electronic components during processing, and also to be able to peel off the electronic components after processing without damaging them (hereinafter also referred to as "high adhesion and easy peeling"). As a means for achieving high adhesion and easy peeling, for example, Patent Document 1 discloses a pressure-sensitive adhesive sheet using a pressure-sensitive adhesive in which a polyfunctional monomer or oligomer having a radiation-polymerizable functional group is bonded to the side chain or main chain of the polymer. By utilizing the fact that the polymer has a radiation-polymerizable functional group, which hardens when irradiated with ultraviolet light, the adhesive strength is reduced by irradiating ultraviolet light during peeling, allowing peeling without leaving any adhesive residue.

[0004] Japanese Patent Application Publication No. 5-32946

[0005] In recent years, in order to respond to the increasing integration density of semiconductors, the TBDB (Temporary Bonding / De-Bonding) process has been adopted, in which semiconductors are manufactured by supporting a thin wafer with a support and a temporary fixing material or adhesive film. The TBDB process may include a step of irradiating the entire surface of the support with laser light to peel off the support. As the laser light to be irradiated, various laser lights such as solid-state laser light and gas laser light are used, and laser light with a wavelength in the ultraviolet region is used to promote photodecomposition. In particular, excimer laser light with a wavelength of 308 nm or more and 355 nm or less is often used.

[0006] However, when an adhesive film such as a conventional pressure-sensitive adhesive film or a temporary fixing material such as a tape-like temporary fixing material is used to peel off the support by irradiating it with laser light, if laser light capable of peeling off the support is continued to be irradiated for a long period of time, this can lead to a decrease in the equipment capacity and processing capacity of the laser light irradiating device, carbonization of the adhesive film or temporary fixing material, damage to the support, contamination of the adhesive film, temporary fixing material, and support, and a decrease in the manufacturing quality of electronic components due to deterioration in the peeling performance of the support, etc.

[0007] Furthermore, in the manufacture of semiconductors, semiconductors are sometimes integrated onto substrates by thermocompression bonding (TCB), and it is therefore necessary to easily peel the adhesive film from the adherend after high-temperature processing, which involves heat treatment or heat generation. However, with conventional adhesive films, adhesion to the adherend increases during high-temperature processing, and the adhesive strength does not decrease sufficiently upon peeling, resulting in adhesive residue.

[0008] The present invention aims to provide an adhesive film that can efficiently peel off a support even when irradiated with low-energy laser light and that has excellent peelability from an adherend even when subjected to high-temperature processing. Another object of the present invention is to provide a cured product of the adhesive film. A further object of the present invention is to provide a laminate having, in this order, a support, the adhesive film, and a semiconductor. A further object of the present invention is to provide a method for producing an electronic component using the laminate, which includes a step of efficiently peeling off a support even when irradiated with low-energy laser light and a step of easily peeling off an adherend even when subjected to high-temperature processing. Another object of the present invention is to provide a temporary fixing material that has excellent laser processing performance and can efficiently peel off a support even when irradiated with low-energy laser light after curing. Another object of the present invention is to provide a cured product of the temporary fixing material. A further object of the present invention is to provide a laminate including the cured product. A still further object of the present invention is to provide a method for producing an electronic component, which includes a step of efficiently peeling off a support even when irradiated with low-energy laser light.

[0009] The present disclosure relates to an adhesive film including an adhesive layer containing a curable adhesive, wherein the curable adhesive is a photocurable adhesive, and the adhesive layer is irradiated with light having a wavelength of 405 nm at an integrated light intensity of 20,000 mJ / cm. ２ The adhesive layer has a gel fraction of 65% by mass or more after irradiation with light having a wavelength of 405 nm so that the integrated light amount is 20,000 mJ / cm ２ After irradiation so that the extinction coefficient for light with a wavelength of 308 nm is 1.0 × 10 －４ The present disclosure 2 is an adhesive film including an adhesive layer containing a curable adhesive, wherein the curable adhesive is a photocurable adhesive, the adhesive layer has a gel fraction of 65 mass % or more after irradiation with light, and the adhesive layer has an extinction coefficient of 1.0 × 10 for light with a wavelength of 308 nm after irradiation with light. －４or more. Disclosure 3 is the adhesive film of Disclosure 1 or 2, wherein the curable adhesive contains a curable resin and a photopolymerization initiator. Disclosure 4 is the adhesive film of Disclosure 3, wherein the curable resin contains a bismaleimide compound. Disclosure 5 is the adhesive film of Disclosure 3 or 4, wherein the photopolymerization initiator has an absorption coefficient of 10 ml / (g cm) or more at a wavelength of 405 nm. Disclosure 6 is the adhesive film of Disclosure 3, 4, or 5, wherein the content of the photopolymerization initiator per 100 parts by mass of the curable resin is 0.1 parts by mass or more and 10 parts by mass or less. Disclosure 7 is the adhesive film of Disclosure 3, 4, 5, or 6, wherein the curable adhesive further contains an ultraviolet absorber. Disclosure 8 is the adhesive film of Disclosure 7, wherein the ultraviolet absorber contains a triazine-based ultraviolet absorber.

[0023] Disclosure 9 is the adhesive film of Disclosure 7 or 8, wherein the content of the ultraviolet absorber relative to 100 parts by mass of the curable resin is 1 part by mass or more and 30 parts by mass or less. Disclosure 10 is the adhesive film of Disclosure 3, 4, 5, 6, 7, 8, or 9, wherein the curable adhesive further contains a release agent. Disclosure 11 is the adhesive film of Disclosure 10, wherein the release agent contains at least one selected from the group consisting of silicone-based release agents and acrylic-based release agents. Disclosure 12 is the adhesive film of Disclosure 10 or 11, wherein the content of the release agent relative to 100 parts by mass of the curable resin is 0.1 parts by mass or more and 20 parts by mass or less. Disclosure 13 is the adhesive film of Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12, wherein the adhesive layer has a gel fraction of 60% by mass or less before light irradiation. The present disclosure 14 is directed to a method for manufacturing a laminated ... －４ The adhesive film of Disclosure 15 is the adhesive film of Disclosure 16, which has a substrate and is irradiated with light of a wavelength of 405 nm at an integrated light intensity of 20,000 mJ / cm. ２The adhesive film of Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15, wherein the 5% weight loss temperature when heated in a nitrogen atmosphere at a temperature increase rate of 10°C / min after irradiation so as to satisfy the above condition is 300°C or higher. Disclosure 17 is the adhesive film of Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16, which is used for temporarily fixing electronic components. Disclosure 18 is a cured product obtained by curing the adhesive film of Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, or 17, wherein the cured product is obtained by curing the adhesive film of Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, or 17, and ... ２ and a cured product having a laser processing depth of 0.10 μm or more when pulsed with laser light of the present disclosure. Disclosure 19 is a laminate having, in this order, a support, an adhesive film of Disclosures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, or 17, and a semiconductor device. Disclosure 20 is a method for producing an electronic component using the laminate of Disclosure 19, the method comprising: a light irradiation step of irradiating the laminate with light from the support side; a high-temperature processing step of subjecting the laminate to a heat treatment or a treatment involving heat generation; a support peeling step of irradiating the laminate from the support side with laser light having a wavelength of 200 nm or more and 355 nm or less to peel the support from the adhesive film; and an adhesive film peeling step of peeling the adhesive film from the semiconductor device. Disclosure 21 is a temporary fixing material containing a curable adhesive, wherein the curable adhesive is a photocurable adhesive, and the adhesive film is irradiated with light of a wavelength of 365 nm at an integrated light intensity of 20,000 mJ / cm. ２ After curing, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ The present disclosure 22 is a temporary fixing material that has a laser processing depth of 0.10 μm or more when pulsed with laser light of a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm after curing. ２The present disclosure 23 is a temporary fixing material that has a laser processing depth of 0.10 μm or more when pulsed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm after curing. ２ The temporary fixing material of Disclosure 21 or 22, wherein the laser processing depth when pulsed with laser light of wavelength 308 nm, pulse width 10 nsec, and irradiation energy density 400 mJ / cm after the curing is 1.0 μm or less. ２ The temporary fixing material of Disclosure 21, 22, or 23, wherein the laser processing depth when pulsed with a laser beam of 1.0 μm or less is 1.0 μm. Disclosure 25 is the temporary fixing material of Disclosure 21, 22, 23, or 24, wherein the curable adhesive contains a curable resin, and the curable resin contains a resin having an imide skeleton in the repeating unit of its main chain. Disclosure 26 is the temporary fixing material of Disclosure 25, wherein the content of the resin having an imide skeleton in the repeating unit of its main chain is 65 parts by mass or more per 100 parts by mass of the curable resin. Disclosure 27 is the temporary fixing material of Disclosure 21, 22, 23, 24, 25, or 26, wherein the curable adhesive contains an ultraviolet absorber or an ultraviolet scattering agent. Disclosure 28 is the temporary fixing material of Disclosure 27, wherein the ultraviolet absorber or the ultraviolet scattering agent contains a triazine-based ultraviolet absorber or titanium oxide. Disclosure 29 is the temporary fixing material of Disclosures 21, 22, 23, 24, 25, 26, 27, or 28, wherein the curable adhesive contains a photopolymerization initiator. Disclosure 30 is the temporary fixing material of Disclosures 21, 22, 23, 24, 25, 26, 27, 28, or 29, wherein the weight loss rate after curing is 7% or less when heated at 290°C for 30 minutes in a nitrogen atmosphere. Disclosure 31 is a cured product obtained by curing the temporary fixing material of Disclosures 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30. Disclosure 32 is a laminate having, in this order, a support, the cured product of Disclosure 31, and a semiconductor device, wherein the support has a light transmittance of 50% or more in the wavelength range of 300 nm to 400 nm. The present disclosure 33 provides a method for applying a laser beam having a wavelength of 308 nm or more and 355 nm or less, a pulse width of 100 nsec or less, and an irradiation energy density of 500 mJ / cm to a laminate including a support, a cured product of a temporary fixing material, and a semiconductor device in this order. ２The method for producing an electronic component includes a support peeling step of peeling the support from the laminate by irradiating the support with pulsed laser light as follows: The present invention will be described in detail below.

[0010] The present inventors focused on the fact that the laser light irradiated to peel the support is high-energy in the production of highly heat-resistant electronic components, which has become increasingly necessary in recent years. They investigated the development of an adhesive film or temporary fixing material that would enable efficient peeling of the support even when irradiated with low-energy laser light, which would minimize damage to the device, support, temporary fixing material, etc. The present inventors used an adhesive film including an adhesive layer containing a curable adhesive, and investigated adjusting the gel fraction of the adhesive layer and the extinction coefficient of the adhesive layer for light of a specific wavelength within a specific range for the adhesive film after light irradiation. As a result, they discovered that an adhesive film could be obtained that could efficiently peel the support even when irradiated with low-energy laser light, and that exhibited excellent peelability from the adherend even when subjected to high-temperature processing, thereby completing the adhesive film of the present invention. Furthermore, the present inventors cured a temporary fixing material containing a curable adhesive, and examined the processing depth when the cured temporary fixing material was irradiated with pulsed laser light. They discovered that using a temporary fixing material that reaches a specific processed state would allow efficient peeling of the support, leading to the completion of the temporary fixing material of the present invention.

[0011] The adhesive film of the present invention includes an adhesive layer containing a curable adhesive. The curable adhesive is a photocurable adhesive. By including an adhesive layer containing a photocurable adhesive in the adhesive film of the present invention, curing by light becomes possible, and increased adhesion of the resulting adhesive film to the adherend during high-temperature processing can be suppressed. As a result, the resulting adhesive film has improved peelability from the adherend, and adhesive residue can be prevented from occurring when peeled from the adherend. A method for curing the adhesive film of the present invention by light includes, for example, using an ultra-high pressure mercury lamp to emit light with a wavelength of 405 nm at an integrated light intensity of 20,000 mJ / cm. ２ Examples of the method include a method of irradiating the light so that the

[0012] The adhesive layer according to the adhesive film of the present disclosure 2 has a lower limit of the gel fraction after light irradiation of 65% by mass. When the gel fraction of the adhesive layer after light irradiation is 65% by mass or more, the resulting adhesive film has excellent releasability from the adherend. The lower limit of the gel fraction of the adhesive layer after light irradiation is preferably 70% by mass, more preferably 75% by mass. Furthermore, in consideration of using a photopolymerization initiator that is not incorporated into crosslinking in order to enhance the curability of the adhesive layer, the upper limit of the gel fraction of the adhesive layer after light irradiation is preferably 99.9% by mass, more preferably 99% by mass. The light irradiation conditions for the gel fraction of the adhesive layer after light irradiation include, for example, a condition where the integrated light dose of light at a wavelength of 405 nm is 20,000 mJ / cm. ２ Examples of such a method include irradiating the light so that the

[0013] The adhesive layer according to the adhesive film of the present disclosure 1 is resistant to light with a wavelength of 405 nm having an integrated light intensity of 20,000 mJ / cm ２ The lower limit of the gel fraction after irradiation so as to obtain a value of 65% by mass (hereinafter, sometimes simply referred to as "gel fraction of the adhesive layer after irradiation with light having a wavelength of 405 nm") is 65% by mass. When the gel fraction of the adhesive layer after irradiation with light having a wavelength of 405 nm is 65% by mass or more, the resulting adhesive film has excellent peelability from the adherend. The lower limit of the gel fraction of the adhesive layer after irradiation with light having a wavelength of 405 nm is preferably 70% by mass, more preferably 75% by mass. Furthermore, in consideration of using a photopolymerization initiator that is not incorporated into crosslinking in order to enhance the curability of the adhesive layer, the upper limit of the gel fraction of the adhesive layer after irradiation with light having a wavelength of 405 nm is preferably 99.9% by mass, more preferably 99% by mass. The gel fraction of the adhesive layer after irradiation with light having a wavelength of 405 nm is measured, for example, by the following method. That is, when the adhesive film is irradiated with light having a wavelength of 405 nm at an integrated light intensity of 20,000 mJ / cm ２ After irradiating the adhesive layer so that the adhesive layer has a mass W ０ (g) The adhesive layer is collected and immersed in toluene at 23°C for 24 hours. After shaking, the adhesive layer is passed through a metal mesh (opening #200 mesh, mass: W １The adhesive layer that has absorbed toluene and swollen is filtered using a filter (g), and the separated adhesive layer is dried at 110° C. for 1 hour. The mass W of the dried adhesive layer is ２ The gel fraction of the adhesive layer after irradiation with light having a wavelength of 405 nm can be measured by measuring the mass (g) of the adhesive layer and calculating the gel fraction using the following formula: Gel fraction (mass%)=100×(W ２ -W １ ) / W ０ (W ０ : Mass of the initial adhesive layer, W １ : initial mass of the metal mesh, W ２ : mass of adhesive layer including metal mesh after drying)

[0014] The adhesive layer preferably has an upper limit of 60% by mass for the gel fraction before light irradiation (hereinafter sometimes simply referred to as the "gel fraction of the adhesive layer before light irradiation"). When the gel fraction of the adhesive layer before light irradiation is 60% by mass or less, the resulting adhesive film has superior adhesiveness. The upper limit of the gel fraction of the adhesive layer before light irradiation is more preferably 50% by mass, and even more preferably 40% by mass. The lower limit of the gel fraction of the adhesive layer before light irradiation may be 0% by mass. However, from the viewpoints of the durability of the adhesive layer against slippage and deformation of the adherend and the adhesion of the resulting adhesive film to the adherend, the lower limit of the gel fraction of the adhesive layer before light irradiation is preferably 0.5% by mass, and more preferably 1% by mass. The gel fraction of the adhesive layer before light irradiation can be measured, for example, by performing the above-described method for measuring the gel fraction of the adhesive layer after light irradiation without light irradiation.

[0015] A preferred method for adjusting the gel fraction of the adhesive layer after light irradiation and the gel fraction of the adhesive layer before light irradiation to fall within the above-mentioned range is to change the composition of the photocurable adhesive (for example, by adjusting the amount of components that do not photocurable, or by adding a photopolymerization initiator to improve photocurability).

[0016] The adhesive layer according to the adhesive film of the present disclosure 2 has a lower limit of the extinction coefficient for light with a wavelength of 308 nm after irradiation of 1.0 × 10 －４ The extinction coefficient of the adhesive layer after irradiation with light at a wavelength of 308 nm is 1.0 × 10－４ By satisfying the above condition, the support can be efficiently peeled off even when irradiated with low-energy laser light. A preferable lower limit of the extinction coefficient of the adhesive layer after irradiation with light having a wavelength of 308 nm is 1.0 × 10 －３ , and a more preferable lower limit is 5.0 × 10 －２ , and a more preferable lower limit is 1.0 × 10 －１ The preferred upper limit of the extinction coefficient of the adhesive layer after irradiation with light for light with a wavelength of 308 nm is 50. When the adhesive layer has an extinction coefficient of 50 or less for light with a wavelength of 308 nm after irradiation with light, the adhesive layer can be processed to a sufficient depth even when irradiated with low-energy laser light, thereby enabling more efficient peeling of the support. The preferred upper limit of the extinction coefficient of the adhesive layer after irradiation with light for light with a wavelength of 308 nm is 20, more preferably 10, and even more preferably 5.0. The light irradiation conditions for the extinction coefficient after irradiation with light of the adhesive layer include, for example, an integrated light amount of 405 nm light of 20,000 mJ / cm. ２ Examples of such a method include irradiating the light so that the

[0017] The adhesive layer according to the adhesive film of the present disclosure 1 is resistant to light with a wavelength of 405 nm having an integrated light intensity of 20,000 mJ / cm ２ The lower limit of the extinction coefficient for light with a wavelength of 308 nm after irradiation so as to satisfy the following condition (hereinafter, this may be simply referred to as "the extinction coefficient for light with a wavelength of 308 nm after irradiation of the adhesive layer with light with a wavelength of 405 nm") is 1.0 × 10 －４ The extinction coefficient of the adhesive layer with respect to light having a wavelength of 308 nm after irradiation with light having a wavelength of 405 nm is 1.0×10 －４ By satisfying the above condition, the support can be efficiently peeled off even when irradiated with low-energy laser light. A preferable lower limit of the extinction coefficient of the adhesive layer with respect to light having a wavelength of 308 nm after irradiation with light having a wavelength of 405 nm is 1.0 × 10 －３ , and a more preferable lower limit is 1.0 × 10 －２ , and a more preferable lower limit is 5.0 × 10 －２ , and an even more preferable lower limit is 1.0 × 10 －１The preferred upper limit of the extinction coefficient of the adhesive layer for light with a wavelength of 308 nm after irradiation with light with a wavelength of 405 nm is 50. When the extinction coefficient of the adhesive layer for light with a wavelength of 308 nm after irradiation with light with a wavelength of 405 nm is 50 or less, the adhesive layer can be processed to a sufficient depth even when irradiated with low-energy laser light, thereby enabling more efficient peeling of the support. The more preferred upper limit of the extinction coefficient of the adhesive layer for light with a wavelength of 308 nm after irradiation with light with a wavelength of 405 nm is 20, even more preferred is 10, and even more preferred is 5.0. The extinction coefficient of the adhesive layer for light with a wavelength of 308 nm after irradiation with light with a wavelength of 405 nm is measured, for example, by the following method. That is, when the integrated light intensity of light with a wavelength of 405 nm is 20,000 mJ / cm ２ The adhesive layer after irradiation is measured for transmittance and reflectance using a spectrophotometer (such as a V-670 manufactured by JASCO Corporation), and the thickness is measured using a thickness gauge (such as a Digimatic Indicator ID-H manufactured by Mitutoyo Corporation). The obtained transmittance, reflectance, and thickness measurement results can be used to measure the extinction coefficient of the adhesive layer of the present invention after irradiation with light at a wavelength of 308 nm by analyzing the measured values ​​using spectroscopic ellipsometry analysis software. When the adhesive film of the present invention has a substrate, the adhesive layer and the substrate can be separated, and the transmittance, reflectance, and thickness of the separated adhesive layer can be measured. The measured values ​​of transmittance, reflectance, and thickness can then be analyzed using spectroscopic ellipsometry analysis software. At wavelengths where the transmittance is 1% or less, it may not be possible to derive an accurate value for the extinction coefficient from the above analysis. Therefore, when the transmittance at a wavelength of 308 nm is 1% or less, it is assumed that the extinction coefficient in the long wavelength region where the transmittance is greater than 1% is used to approximate an exponential function, and the equation of the approximate curve (y = A (constant) × e^(B (constant) × x), y: extinction coefficient, x: wavelength (nm)) is found by the least squares method, and the extinction coefficient k at a wavelength of 308 nm is calculated from the equation of the approximate curve obtained. When the wavelength at which the transmittance is 1% or less is shorter than 308 nm, the extinction coefficient k at a wavelength of 308 nm can be found from the above analysis results.

[0018] The preferred lower limit of the extinction coefficient of the adhesive layer with respect to light having a wavelength of 308 nm before irradiation with light (hereinafter, sometimes simply referred to as "extinction coefficient of the adhesive layer with respect to light having a wavelength of 308 nm before irradiation with light") is 1.0 × 10 －４ The extinction coefficient of the adhesive layer with respect to light with a wavelength of 308 nm before irradiation is 1.0 × 10 －４ By satisfying the above, the extinction coefficient of the adhesive layer with respect to light having a wavelength of 308 nm after irradiation with light can be easily adjusted to fall within the above range. A more preferable lower limit of the extinction coefficient of the adhesive layer with respect to light having a wavelength of 308 nm before irradiation with light is 1.0 × 10 －３ , and a more preferable lower limit is 1.0 × 10 －２ , and an even more preferable lower limit is 5.0 × 10 －２ The preferred upper limit of the extinction coefficient of the adhesive layer for light with a wavelength of 308 nm before irradiation is 50. When the extinction coefficient of the adhesive layer for light with a wavelength of 308 nm before irradiation is 50 or less, the adhesive layer can be processed to a sufficient depth even when irradiated with low-energy laser light, thereby enabling more efficient peeling of the support. The preferred upper limit of the extinction coefficient of the adhesive layer for light with a wavelength of 308 nm before irradiation is 20, and even more preferred is 10. The extinction coefficient of the adhesive layer for light with a wavelength of 308 nm before irradiation can be measured, for example, by measuring the extinction coefficient of the adhesive layer for light with a wavelength of 308 nm after irradiation without irradiating the adhesive layer with light before measurement.

[0019] A preferred method for adjusting the extinction coefficient for light with a wavelength of 308 nm after irradiation of the adhesive layer and the extinction coefficient for light with a wavelength of 308 nm before irradiation of the adhesive layer to within the above-mentioned range is to change the type and content of the composition of the curable adhesive (for example, the ultraviolet absorber described below).

[0020] The curable adhesive is included, and after the curable adhesive is cured, the wavelength is 308 nm, the pulse width is 10 nsec, and the irradiation energy density is 300 mJ / cm ２The present invention also includes a temporary fixing material having a laser processing depth of 0.10 μm or more when irradiated with pulsed laser light. The temporary fixing material of the present invention has excellent laser processing resistance, even when irradiated with low-energy laser light after curing, and can efficiently peel off the support. In this specification, the term "laser processing depth" refers to the depth of removal of the cured temporary fixing material observed from the surface of the cured temporary fixing material on the laser light irradiated side after irradiating the cured temporary fixing material with pulsed laser light.

[0021] The curable adhesive may be a photocurable adhesive that is cured by irradiation with light, or a thermosetting adhesive that is cured by heating in a high-temperature environment. Among these, a photocurable adhesive is preferred from the viewpoint of peelability after heating.

[0022] The photocurable adhesive may be cured by, for example, applying light of 365 nm wavelength at an integrated light intensity of 20,000 mJ / cm ２ The method of irradiating light with a wavelength of 405 nm so that the cumulative light amount is 20,000 mJ / cm ２ The light having a wavelength of 365 nm is irradiated so that the cumulative light amount is 20,000 mJ / cm. ２ Examples of light sources used in the method of irradiating the adhesive so that the integrated light intensity is 20,000 mJ / cm include an ultra-high pressure mercury lamp, an LED, and a metal halide lamp. ２ After irradiation, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ The present invention also provides a temporary fixing material that has a laser processing depth of 0.10 μm or more when pulsed with the above laser light.

[0023] Examples of methods for curing the thermosetting adhesive include a method of heating at 290° C. for 30 minutes in a nitrogen atmosphere, and a method of heating at 150° C. for 30 minutes in an oxygen atmosphere.

[0024] The temporary fixing material according to the present disclosure 22 has a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm after hardening. ２The lower limit of the laser processing depth when pulsed irradiation with laser light of wavelength 308 nm, pulse width 10 nsec, and irradiation energy density 300 mJ / cm is 0.10 μm. ２ The laser processing depth is 0.10 μm or more when pulsed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm. Therefore, the temporary fixing material after hardening can be efficiently peeled off from the support even when irradiated with a low-energy laser beam. ２ The lower limit of the laser processing depth when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is preferably 0.15 μm, and more preferably 0.20 μm. ２ The preferred upper limit of the laser processing depth when pulsed irradiation is performed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is 1.0 μm. ２ When the laser processing depth is 1.0 μm or less when pulsed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm, the temporary fixing material after hardening has improved laser processing resistance, and the support can be peeled off more efficiently. ２ The upper limit of the laser processing depth when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is more preferably 0.80 μm, and even more preferably 0.60 μm. ２ When the temporary fixing material of the present invention is not in a liquid or paste form, the lower limit of the laser processing depth when pulsed irradiated with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is sufficient as long as at least one surface of the cured temporary fixing material satisfies the above range, but it is preferable that the lower limit of the laser processing depth when pulsed irradiated with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is satisfied on both surfaces of the cured temporary fixing material. ２When the temporary fixing material of the present invention is not liquid or paste-like, the upper limit of the laser processing depth when pulsed with laser light preferably satisfies the above range on at least one surface of the cured temporary fixing material, but more preferably on both surfaces of the cured temporary fixing material. Furthermore, the laser processing depth in this specification can be measured, for example, by irradiating the cured temporary fixing material with pulsed laser light, and then measuring the step height of the surface of the cured temporary fixing material on the side irradiated with the laser light using a laser microscope. Examples of the laser microscope include the OLS4100-SAT (manufactured by Olympus Corporation, wavelength 405 nm).

[0025] The temporary fixing material according to the present disclosure 21 is irradiated with light of a wavelength of 365 nm at an integrated light intensity of 20,000 mJ / cm ２ After irradiation, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ The lower limit of the laser processing depth when pulsed irradiation with the above-mentioned 365 nm wavelength laser light is 0.10 μm. ２ After irradiation so as to obtain the following, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ When the laser beam having a wavelength of 365 nm is pulsed, the laser processing depth is 0.10 μm or more, so that the temporary fixing material after hardening can be efficiently peeled off from the support even when irradiated with low-energy laser beam. ２ After irradiation so as to obtain the following, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ The lower limit of the laser processing depth when pulsed irradiation with the laser light of wavelength 365 nm is preferably 0.15 μm, and more preferably 0.20 μm. ２ After irradiation so as to obtain the following, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ The preferred upper limit of the laser processing depth when pulsed irradiation with the above-mentioned laser light of 365 nm wavelength is 1.0 μm. ２After irradiation so as to obtain the following, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ When the laser processing depth when pulsed with the laser light of 365 nm is 1.0 μm or less, the laser processing resistance of the temporary fixing material after hardening is further improved, and the support can be peeled off more efficiently. ２ After irradiation so as to obtain the following, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ When the temporary fixing material of the present invention is not in a liquid or paste form, the laser processing depth when pulsed with the above-mentioned laser light of 365 nm is more preferably 0.80 μm, and even more preferably 0.60 μm. ２ After irradiation so as to obtain the following, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ The lower limit of the laser processing depth when pulsed irradiation with the laser light of 365 nm wavelength is performed should be within the above range on at least one surface of the cured temporary fixing material, but it is preferable that the above range be satisfied on both surfaces of the cured temporary fixing material. ２ After irradiation so as to obtain the following, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ The upper limit of the laser processing depth when pulsed irradiation with the laser light of the above range is preferably satisfied on at least one surface of the cured temporary fixing material, but more preferably satisfied on both surfaces of the cured temporary fixing material.

[0026] After hardening, the temporary fixing material was irradiated with a wavelength of 308 nm, a pulse width of 10 nsec, and an energy density of 400 mJ / cm ２ The preferred upper limit of the laser processing depth when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is 1.0 μm. ２When the laser processing depth is 1.0 μm or less when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is performed, the laser processing performance of the hardened temporary fixing material is further improved, and the support can be peeled off more efficiently. ２ The upper limit of the laser processing depth when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is more preferably 0.80 μm, and even more preferably 0.60 μm. ２ The preferred lower limit of the laser processing depth when pulsed irradiation is performed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is 0.10 μm. ２ When the laser processing depth is 0.10 μm or more when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is performed, the laser processing performance of the cured temporary fixing material is further improved, and the support can be peeled off more efficiently. ２ When the temporary fixing material of the present invention is not in a liquid or paste form, the lower limit of the laser processing depth when pulsed irradiation is performed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is more preferably 0.15 μm, and even more preferably 0.20 μm. ２ The laser processing depth when pulsed irradiation of the laser light of the above range is preferably within the above range on at least one surface of the cured temporary fixing material, but more preferably within the above range on both surfaces of the cured temporary fixing material.

[0027] The wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ and the laser processing depth when pulsed with laser light of wavelength 308 nm, pulse width 10 nsec, and irradiation energy density 400 mJ / cm ２ Examples of a method for adjusting the laser processing depth when pulsed irradiation with the laser beam include a method for adjusting the composition of a curable adhesive. Furthermore, when the temporary fixing material is used in a laminate described below, the laser processing depth can also be adjusted by a method for using a support having a high transmittance for light with a wavelength of 308 nm.

[0028] The curable adhesive preferably contains a curable resin. The curable resin preferably contains a resin having an imide skeleton in the repeating unit of the main chain. When the curable adhesive contains a resin having the imide skeleton in the repeating unit of the main chain, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to be cured by light irradiation, which can further suppress increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, making it possible to more effectively prevent adhesive residue from being left behind when peeled from the adherend. Furthermore, the resin having the imide skeleton in the repeating unit of the main chain has extremely excellent heat resistance due to the imide skeleton, and is less likely to decompose the main chain even when subjected to high-temperature processing at 300°C or higher. For this reason, by including a resin having an imide skeleton in the main chain repeating unit in the photocurable adhesive, the adhesive film and the temporary fixing material can further suppress the occurrence of voids and lifting between the adhesive film and the support during high-temperature processing. Also, because the adhesive film and the temporary fixing material can further suppress increased adhesion to the adherend during high-temperature processing, the peelability from the adherend is further improved, and the occurrence of adhesive residue when peeled from the adherend can be further prevented.

[0029] The resin having the imide skeleton in the repeating unit of the main chain preferably has a constitutional unit represented by the following formula (1).

[0030]

[0031] In the above formula (1), P １ is preferably an aromatic group having 5 to 50 carbon atoms. １When the carbon number is an aromatic group having 5 to 50 carbon atoms, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to be cured by light irradiation, which can further suppress increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, and can further prevent adhesive residue from occurring when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. That is, the occurrence of voids and lifting between the adhesive film and the support during high-temperature processing can be further suppressed. Furthermore, the adhesive film and the cured temporary fixing material can further suppress increased adhesion to the adherend during high-temperature processing, which can further improve releasability from the adherend, and can further prevent adhesive residue from occurring when peeled from the adherend.

[0032] In the above formula (1), Q １ is preferably a substituted or unsubstituted linear, branched or cyclic aliphatic group having from 2 to 100 carbon atoms. １ is a substituted or unsubstituted linear, branched or cyclic aliphatic group having from 2 to 100 carbon atoms, the adhesive film and the temporary fixing material have excellent flexibility, can exhibit high conformability to an adherend having irregularities, and can be more easily peeled off. １ is preferably an aliphatic group derived from a diamine compound. In particular, from the viewpoints of flexibility and compatibility with solvents and other components of the resin having the imide skeleton in the main chain repeating unit, １is preferably an aliphatic group derived from a dimer diamine. The dimer diamine is a diamine compound obtained by reducing and amminating cyclic and acyclic dimer acids obtained as dimers of unsaturated fatty acids, and examples thereof include linear, monocyclic, and polycyclic dimer diamines. The dimer diamine may contain a carbon-carbon double bond or may be a hydrogenated product to which hydrogen has been added.

[0033] The aliphatic group derived from the dimer diamine is preferably at least one group selected from the group consisting of a group represented by the following formula (2-1), a group represented by the following formula (2-2), a group represented by the following formula (2-3), and a group represented by the following formula (2-4). Among these, the group represented by the following formula (2-2) is more preferred.

[0034]

[0035] In the above formulas (2-1) to (2-4), R １ ~R １６ are each independently a linear or branched hydrocarbon group, and * represents a bond, which bonds to N in the above formula (1).

[0036] In the above formulas (2-1) to (2-4), R １ ~R １６ The hydrocarbon group represented by R may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. １ and R ２ , R ３ and R ４ , R ５ and R ６ , R ７ and R ８ , R ９ and R １０ , R １１ and R １２ , R １３ and R １４ , and R １５ and R １６The total number of carbon atoms is preferably 7 or more and 50 or less. When the total number of carbon atoms is within the above range, the resin having an imide skeleton in the repeating unit of the main chain has better compatibility with solvents and other components, and the adhesive film and the temporary fixing material have better flexibility. The total number of carbon atoms is more preferably 9 or more, even more preferably 12 or more, and still more preferably 14 or more. The total number of carbon atoms is more preferably 35 or less, even more preferably 25 or less, and still more preferably 18 or less.

[0037] In the group represented by the formula (2-1), the group represented by the formula (2-2), the group represented by the formula (2-3), and the group represented by the formula (2-4), the optical isomerism is not particularly limited, and any optical isomerism is included.

[0038] The preferred lower limit of the content of the resin having an imide skeleton in the main chain repeating unit per 100 parts by mass of the curable resin is 40 parts by mass, and the preferred upper limit is 100 parts by mass. When the content of the resin having an imide skeleton in the main chain repeating unit is within this range, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling from the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to be cured by light irradiation, thereby further suppressing increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, making it possible to more effectively prevent adhesive residue from occurring when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. That is, the occurrence of voids and lifting between the adhesive film and the support during high-temperature processing can be further suppressed. Furthermore, during high-temperature processing, the adhesive film and the hardened temporary fixing material can further suppress increased adhesion to the adherend, thereby further improving the releasability from the adherend and more effectively preventing adhesive residue from being left behind when peeled from the adherend.

[0039] The resin having an imide skeleton in a repeating unit of the main chain preferably does not have a functional group having a carbon-carbon double bond and includes a resin having an imide skeleton in a repeating unit of the main chain. Note that a carbon-carbon double bond contained in an aromatic ring is not considered to be the carbon-carbon double bond of the functional group having a carbon-carbon double bond.

[0040] The resin having no functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain preferably has a weight-average molecular weight of 20,000 (lower limit) and 2,000,000 (upper limit). When the resin having no functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain has a weight-average molecular weight of 20,000 or more, the adhesive film and the cured temporary fixing material have excellent heat resistance. That is, the adhesive film and the cured temporary fixing material can further suppress the occurrence of voids and lifting between the adhesive film and the support during high-temperature processing. Furthermore, the adhesive film and the cured temporary fixing material can further suppress increased adhesion to the adherend during high-temperature processing, thereby further improving releasability from the adherend and more effectively preventing adhesive residue from being left behind when peeled from the adherend. When the weight-average molecular weight of the resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in its main chain repeating unit is 2,000,000 or less, the resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in its main chain repeating unit has better compatibility with solvents and other components. A more preferred lower limit of the weight-average molecular weight of the resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in its main chain repeating unit is 40,000, and a more preferred upper limit is 600,000. Note that, in this specification, the weight-average molecular weight is measured as a polystyrene-equivalent molecular weight by gel permeation chromatography (GPC). Specifically, for example, it can be measured using an APC system (manufactured by Waters Corporation) under the following conditions: a mobile phase of THF, a flow rate of 1.0 ml / min, a column temperature of 40°C, a sample concentration of 0.2% by mass, and an RI-PDA detector. The column may be, for example, HR-MB-M 6.0×150 mm (manufactured by Waters Corporation).

[0041] Specific examples of the resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in the repeating unit of the main chain include resins that have a constitutional unit represented by the above formula (1) and have functional groups that do not have a carbon-carbon double bond at both terminals.

[0042] The resin having a structural unit represented by the above formula (1) and a functional group having no carbon-carbon double bond at both ends may have a structural unit represented by the following formula (3).

[0043]

[0044] In the above formula (3), P ２ represents an aromatic group; ２ represents a group having a substituted or unsubstituted aromatic structure.

[0045] In the above formula (3), P ２ is preferably an aromatic group having 5 to 50 carbon atoms. ２ When the carbon number is an aromatic group having 5 to 50 carbon atoms, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to be cured by light irradiation, which can further suppress increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, and can more effectively prevent adhesive residue from occurring when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. That is, the adhesive film and the cured temporary fixing material can more effectively prevent voids and lifting from occurring between the adhesive film and the support during high-temperature processing. Furthermore, the adhesive film and the cured temporary fixing material can more effectively suppress increased adhesion to the adherend during high-temperature processing, thereby further improving releasability from the adherend and more effectively preventing adhesive residue from occurring when peeled from the adherend.

[0046] In the above formula (3), Q ２is preferably a substituted or unsubstituted group having an aromatic structure having 5 to 50 carbon atoms. ２ When the group is a substituted or unsubstituted group having an aromatic structure with 5 to 50 carbon atoms, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to be cured by light irradiation, which further suppresses increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved peelability from the adherend, making it possible to more effectively prevent adhesive residue from occurring when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. That is, the adhesive film and the cured temporary fixing material can more effectively suppress the occurrence of voids and lifting between the adhesive film and the support during high-temperature processing. Furthermore, the adhesive film and the hardened temporary fixing material can further suppress increased adhesion to the adherend during high-temperature processing, thereby improving the releasability from the adherend and more effectively preventing adhesive residue from being left behind when peeled from the adherend.

[0047] Examples of the functional group not having a carbon-carbon double bond include an aliphatic group, an alicyclic group, an aromatic group, an acid anhydride group, and an amino group. Specific examples include an unreacted terminal group of an acid anhydride or diamine compound that is a raw material for a resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in the repeating unit of its main chain. The functional groups not having a carbon-carbon double bond at both ends of a resin that has a structural unit represented by formula (1) and has functional groups not having a carbon-carbon double bond at both ends may be the same or different.

[0048] The content of the structural unit represented by the formula (1) in a resin having a structural unit represented by the formula (1) and a functional group having no carbon-carbon double bonds at both ends is preferably 30 mol% or more, more preferably 50 mol% or more, and preferably 90 mol% or less, more preferably 80 mol% or less. When a resin having a structural unit represented by the formula (1) and a functional group having no carbon-carbon double bonds at both ends has a structural unit represented by the formula (3), the content of the structural unit represented by the formula (3) is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 20 mol% or more, and preferably 50 mol% or less, more preferably 30 mol% or less. In the structural unit represented by the formula (1) and the structural unit represented by the formula (3), by the content of each structural unit being within the above range, the adhesive film and the cured temporary fixing material can be more effectively prevented from generating voids and lifting between the support during high-temperature processing, and can be more easily peeled off from the adherend. The structural unit represented by the above formula (1) and the structural unit represented by the above formula (3) may have a block structure consisting of block components in which the respective structural units are arranged consecutively, or may have a random structure in which the respective structural units are arranged randomly.

[0049] Examples of a method for producing a resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in the repeating unit of the main chain include a method of reacting a diamine compound with an aromatic acid anhydride.

[0050] The diamine compound can be either an aliphatic diamine compound or an aromatic diamine compound. By using an aliphatic diamine compound as the diamine compound, the adhesive layer and the temporary fixing material have superior flexibility, can exhibit high conformability to uneven adherends, and can be more easily peeled off. Furthermore, by using an aromatic diamine compound as the diamine compound, the adhesive film and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to harden upon light irradiation, thereby further suppressing increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved peelability from the adherend, and adhesive residue upon peeling from the adherend can be more effectively prevented. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. The diamine compounds may be used alone or in combination of two or more.

[0051] Examples of the aliphatic diamine compound include 1,10-diaminodecane, 1,12-diaminododecane, dimer diamine, 1,2-diamino-2-methylpropane, 1,2-diaminocyclohexane, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,7-diaminoheptane, 1,8-diaminomenthane, 1,8-diaminooctane, 1,9-diaminononane, 3,3'-diamino-N-methyldipropylamine, diaminomaleonitrile, 1,3-diaminopentane, bis(4-amino-3-methylcyclohexyl)methane, 1,2-bis(2-aminoethoxy)ethane, and 3(4),8(9)-bis(aminomethyl)tricyclo(5.2.1.02,6)decane.

[0052] Among the above aliphatic diamine compounds, dimer diamine is preferred from the viewpoints of flexibility and compatibility with solvents and other components of resins that do not have a functional group having a carbon-carbon double bond and have an imide skeleton in the repeating unit of their main chain. Specific examples of the dimer diamine include dimer diamines that can constitute at least one group selected from the group consisting of the group represented by the above formula (2-1), the group represented by formula (2-2), the group represented by formula (2-3), and the group represented by formula (2-4).

[0053] Examples of the aromatic diamine compound include 9,10-diaminophenanthrene, 4,4'-diaminooctafluorobiphenyl, 3,7-diamino-2-methoxyfluorene, 4,4'-diaminobenzophenone, 3,4-diaminobenzophenone, 3,4-diaminotoluene, 2,6-diaminoanthraquinone, 2,6-diaminotoluene, 2,3-diaminotoluene, 1,8-diaminonaphthalene, 2,4-diaminotoluene, 2,5-diaminotoluene, 1,4-diaminoanthraquinone, 1,5-diamino Aminoanthraquinone, 1,5-diaminonaphthalene, 1,2-diaminoanthraquinone, 2,4-cumenediamine, 1,3-bisaminomethylbenzene, 1,3-bisaminomethylcyclohexane, 2-chloro-1,4-diaminobenzene, 1,4-diamino-2,5-dichlorobenzene, 1,4-diamino-2,5-dimethylbenzene, 4,4'-diamino-2,2'-bistrifluoromethylbiphenyl, bis(amino-3-chlorophenyl)ethane, bis(4-amino-3,5-dimethylphenyl)methan fluorene, bis(4-amino-3,5-diethylphenyl)methane, 9,9'-bis(4-amino-3-ethyldiaminofluorene), 2,3-diaminonaphthalene, 2,3-diaminophenol, bis(4-amino-5-methylphenyl)methane, bis(4-amino-3-methylphenyl)methane, bis(4-amino-3-ethylphenyl)methane, 4,4'-diaminophenyl sulfone, 3,3'-diaminophenyl sulfone, bis(4-(4-aminophenoxy)phenyl)sulfone, bis(4-(3-aminophenyl)phenyl)sulfone Bis(phenoxy)phenyl)sulfone, 4,4'-oxydianiline, 4,4'-diaminodiphenyl sulfide, 3,4'-oxydianiline, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-diamino-3,3'-dihydroxybiphenyl, 4,4'-diamino-3,3'-dimethylbiphenyl, 4,4'-diamino-3,3'-dimethoxybiphenyl, Bisaniline M, Bisaniline P, 9,9-bis(4-aminophenyl)fluorene, o-tolidine sulfone, 5,5'-methylenebis(anthranilic acid), 1,Examples of the amines include 3-bis(4-aminophenoxy)-2,2-dimethylpropane, 1,3-bis(4-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 2,3,5,6-tetramethyl-1,4-phenylenediamine, 3,3',5,5'-tetramethylbenzidine, 4,4'-diaminobenzanilide, 2,2-bis(4-aminophenyl)hexafluoropropane, polyoxyalkylenediamines (e.g., Jeffamine D-230, D-400, D-2000, D-4000, etc., manufactured by Huntsman), 1,3-cyclohexanebis(methylamine), m-xylylenediamine, and p-xylylenediamine.

[0054] Examples of the aromatic acid anhydride include pyromellitic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,4,5-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 3,3',4,4'-benzophenonetetracarboxylic acid, 3,3',4,4'-biphenylethertetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,5,6-pyridinetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 4,4'-sulfonyldiphthalic acid, 1-trifluoromethyl-2,3,5,6-benzenetetracarboxylic acid, 2,2',3,3'-biphenyltetracarboxylic acid, 2,2-bis(3,4-dicarboxyphenyl)propane, 2,2-bis(2,3-dicarboxyphenyl)propane, 1,1-bis(2,3-dicarboxyphenyl)propane, bis(3,4-dicarboxyphenyl)ethane, 1,1-bis(3,4-dicarboxyphenyl)ethane, bis(2,3-dicarboxyphenyl)methane, bis(3,4-dicarboxyphenyl)methane, bis(3,4-dicarboxyphenyl)sulfone, bis(3,4-dicarboxyphenyl)ether, benzene-1,2,3,4-tetracarboxylic acid, 2,2',3,3'-benzophenonetetracarboxylic acid, 2,3,3',4'-benzophenonetetracarboxylic acid, phenanthrene-1,8,9,10-tetracarboxylic acid, pyrazine-2,3,5,6-tetracarboxylic acid, thiophene-2,3,4,5-tetracarboxylic acid, 2,3,3',4'-biphenyltetracarboxylic acid, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide, 4,4'-(4,4'-isopropylidenediphenoxy)-bis(phthalic acid), and other carboxylic acid anhydrides.

[0055] The preferred lower limit of the content of the resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in the repeating unit of its main chain per 100 parts by mass of the curable resin is 10 parts by mass, and the preferred upper limit is 90 parts by mass. When the content of the resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in the repeating unit of its main chain is within this range, the adhesive film and the cured temporary fixing material can be more easily released from the adherend. From the viewpoint of further improving release performance, the more preferred lower limit of the content of the resin that does not have a functional group having a carbon-carbon double bond and has an imide skeleton in the repeating unit of its main chain is 20 parts by mass, and the more preferred upper limit is 80 parts by mass.

[0056] The resin having an imide skeleton in the repeating unit of its main chain preferably contains a resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain. By including a resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain, support materials can be more efficiently peeled off even when irradiated with low-energy laser light. Furthermore, the adhesive film and the temporary fixing material are uniformly and quickly polymerized and crosslinked throughout the entire surface by irradiation with light, etc., and the elastic modulus increases, significantly reducing the adhesive strength of the adhesive film and the temporary fixing material. Therefore, the adhesive film and the cured temporary fixing material can be more effectively prevented from increasing their adhesion to the adherend during high-temperature processing, improving releasability from the adherend and preventing adhesive residue from occurring during peeling. When the resin having an imide skeleton in a repeating unit of its main chain does not have the functional group having a carbon-carbon double bond and includes a resin having an imide skeleton in a repeating unit of its main chain, it is preferable that the resin further includes a resin having a functional group having a carbon-carbon double bond and having an imide skeleton in a repeating unit of its main chain, in addition to the resin having no functional group having a carbon-carbon double bond and having an imide skeleton in a repeating unit of its main chain.

[0057] Examples of the functional group having a carbon-carbon double bond include an optionally substituted maleimide group, a citraconic group, a vinyl ether group, an allyl group, and a (meth)acryloyl group. Among these, an optionally substituted maleimide group is preferred because it provides higher heat resistance. In this specification, "(meth)acryloyl" means acryloyl or methacryloyl.

[0058] The resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain preferably has a functional group equivalent (weight average molecular weight / number of functional groups with carbon-carbon double bonds) of 4,000 or less. Having a functional group equivalent of 4,000 or less allows for more efficient peeling of the support, even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to be cured by light irradiation, thereby further suppressing increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, and adhesive residue upon peeling from the adherend can be more effectively prevented. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. This is thought to be because the presence of functional groups with carbon-carbon double bonds at a density above a certain level in the resin molecules shortens the intercrosslink distance, thereby further suppressing increased adhesion. The functional group equivalent of the functional group having a carbon-carbon double bond is more preferably not more than 3000, and even more preferably not more than 2000. There is no particular preferred lower limit to the functional group equivalent of the functional group having a carbon-carbon double bond, but the substantial lower limit is about 600.

[0059] The resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain preferably has a weight-average molecular weight of 1,000 or more and 100,000 or less. When the resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain has a weight-average molecular weight of 1,000 or more, support materials can be more efficiently peeled off even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to be cured by light irradiation, which can further suppress increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, and adhesive residue can be more effectively prevented from occurring when peeled from the adherend. Furthermore, the curable adhesive is easily formed into a film, and the adhesive film and the temporary fixing material exhibit a certain degree of flexibility, allowing them to exhibit high conformability to adherends having uneven surfaces and allowing for easier peeling. When the weight-average molecular weight of the resin having the functional group having a carbon-carbon double bond and having an imide skeleton in the repeating unit of its main chain is 100,000 or less, the resin having the functional group having a carbon-carbon double bond and having an imide skeleton in the repeating unit of its main chain has better compatibility with solvents and other components. The weight-average molecular weight of the resin having the functional group having a carbon-carbon double bond and having an imide skeleton in the repeating unit of its main chain is more preferably 1,500 or more and 50,000 or less, and even more preferably 2,000 or more and less than 20,000.

[0060] In the resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of the main chain, the functional group with a carbon-carbon double bond may be located either in a side chain or at a terminal, but is preferably located at both terminals, and more preferably located in both terminals and also in the side chain. The functional groups with a carbon-carbon double bond at both terminals of the resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of the main chain are highly reactive, allowing the adhesive layer and the temporary fixing material to be more fully cured by irradiation with light, etc. As a result, the adhesive film and the cured temporary fixing material can be more effectively prevented from increasing their adhesion to the adherend during high-temperature processing, thereby improving releasability from the adherend and more effectively preventing adhesive residue from being left behind during peeling. Furthermore, the support can be more efficiently peeled off even when irradiated with low-energy laser light. Furthermore, the presence of the functional group having a carbon-carbon double bond in the side chain of the resin having an imide skeleton in the repeating unit of its main chain allows for more efficient peeling of the support, even when irradiated with low-energy laser light. The adhesive film and the temporary fixing material also have superior heat resistance. This is believed to be due to the shorter inter-crosslink distance, which further suppresses adhesion enhancement. Furthermore, the presence of the functional group having a carbon-carbon double bond in the side chain of the resin having an imide skeleton in the repeating unit of its main chain makes it easy to adjust the functional group equivalent to 4000 or less while maintaining the weight-average molecular weight at 1000 or more. This allows the adhesive film and the cured temporary fixing material to have sufficient initial adhesive strength, while also preventing adhesion enhancement and adhesive residue during peeling. Furthermore, the support can be more efficiently peeled off, even when irradiated with low-energy laser light.

[0061] As described above, in a resin having a functional group having a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain, the functional group having a carbon-carbon double bond may be located either in a side chain or at a terminal. When either the side chain or the terminal has a functional group other than a functional group having a carbon-carbon double bond (a functional group not having a carbon-carbon double bond), examples of the functional group not having a carbon-carbon double bond include aliphatic groups, alicyclic groups, aromatic groups, acid anhydride groups, and amino groups. Specific examples include unreacted terminal groups of acid anhydrides and diamine compounds that are raw materials for resins having the functional group having a carbon-carbon double bond and an imide skeleton in the repeating unit of their main chain. When a resin having a functional group having a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain has two or more functional groups not having a carbon-carbon double bond in a side chain or at a terminal, the functional groups not having a carbon-carbon double bond may be the same or different.

[0062] Specific examples of the resin having a functional group having a carbon-carbon double bond and an imide skeleton in the repeating unit of the main chain include resins having a constitutional unit represented by the above formula (1) and having a functional group having a carbon-carbon double bond at least in either the terminal or the side chain.

[0063] The resin having a structural unit represented by the above formula (1) and a functional group having a carbon-carbon double bond at least at either the terminal or the side chain may have at least one structural unit selected from the group consisting of a structural unit represented by the following formula (4-1) and a structural unit represented by the following formula (4-2):

[0064]

[0065] In formula (4-1), P ３ represents an aromatic group; ３ represents a group having a substituted or unsubstituted aromatic structure, and in formula (4-2), P ４ represents an aromatic group, R represents a substituted or unsubstituted branched aliphatic group or aromatic group, and X represents a functional group having a carbon-carbon double bond.

[0066] P in the above formula (4-1) ３ and P in the above formula (4-2) ４ is preferably an aromatic group having 5 to 50 carbon atoms. ３ and P ４ When the C1 / C12 aromatic group is an aromatic group having 5 to 50 carbon atoms, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to harden upon light irradiation, thereby further suppressing increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, making it possible to more effectively prevent adhesive residue from occurring when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. That is, the adhesive film and the cured temporary fixing material can more effectively prevent voids and lifting from occurring between the adhesive film and the support during high-temperature processing. Furthermore, the adhesive film and the cured temporary fixing material can more effectively suppress increased adhesion to the adherend during high-temperature processing, making it possible to more effectively prevent adhesive residue from occurring when peeled from the adherend.

[0067] In the above formula (4-1), Q ３ is preferably a substituted or unsubstituted group having an aromatic structure having 5 to 50 carbon atoms. ３When R is a substituted or unsubstituted group having an aromatic structure containing 5 to 50 carbon atoms, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to harden upon irradiation with light, thereby further suppressing increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved peelability from the adherend, making it possible to more effectively prevent adhesive residue from being left behind when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. That is, the adhesive film and the cured temporary fixing material can more effectively prevent voids and lifting from forming between the adhesive film and the support during high-temperature processing. Furthermore, the adhesive film and the hardened temporary fixing material can further suppress increased adhesion to the adherend during high-temperature processing, thereby further improving the releasability from the adherend and more effectively preventing adhesive residue from being left behind when peeled from the adherend.

[0068] In the above formula (4-2), R is preferably a substituted or unsubstituted branched aliphatic or aromatic group having 2 to 100 carbon atoms. When R is a substituted or unsubstituted branched aliphatic or aromatic group having 2 to 100 carbon atoms, the adhesive film and the temporary fixing material have excellent flexibility, can exhibit high conformability to an adherend having irregularities, and can be more easily peeled off.

[0069] In the formula (4-2), R is an aromatic group having an aromatic ester group or an aromatic ether group, and the aromatic ester group or aromatic ether group in R is preferably bonded to X. Here, the "aromatic ester group" refers to a group in which an ester group is directly bonded to an aromatic ring, and the "aromatic ether group" refers to a group in which an ether group is directly bonded to an aromatic ring. By converting the moiety bonded to the ester group or ether group into an aromatic group, the adhesive layer and the cured temporary fixing material are more absorptive of ultraviolet light, allowing for more efficient peeling of the support even when irradiated with low-energy laser light. Furthermore, the adhesive layer and the temporary fixing material are more likely to harden upon light irradiation, thereby further suppressing increased adhesion to the adherend during high-temperature processing. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, making it possible to more effectively prevent adhesive residue from being left behind when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have superior heat resistance. That is, the adhesive film and the cured temporary fixing material can further suppress the occurrence of voids and lifting between the adhesive film and the support during high-temperature processing. Furthermore, the adhesive film and the cured temporary fixing material can further suppress increased adhesion to the adherend during high-temperature processing, thereby further improving the releasability from the adherend and further preventing adhesive residue from occurring when peeled from the adherend. Meanwhile, because X is bonded to R via an aromatic ester group or an aromatic ether group, the carbon-carbon double bond in X is not conjugated with R, and therefore does not interfere with polymerization and crosslinking when heated or irradiated with light.

[0070] The content of the structural unit represented by the formula (1) in a resin having a functional group having a carbon-carbon double bond at at least one of the terminal and the side chain is preferably 30 mol% or more, more preferably 50 mol% or more, and preferably 90 mol% or less, more preferably 80 mol% or less. When a resin having a structural unit represented by the formula (1) and a functional group having a carbon-carbon double bond at at least one of the terminal and the side chain has a structural unit represented by the formula (4-1), the content of the structural unit represented by the formula (4-1) is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 20 mol% or more, and preferably 50 mol% or less, more preferably 30 mol% or less. When a resin having a structural unit represented by the formula (1) and a functional group having a carbon-carbon double bond at at least one of the terminal and the side chain has a structural unit represented by the formula (4-2), the content of the structural unit represented by the formula (4-2) is preferably 10 mol% or more, more preferably 20 mol% or more, and preferably 50 mol% or less, more preferably 30 mol% or less. In the structural unit represented by the formula (1), the structural unit represented by the formula (4-1), and the structural unit represented by the formula (4-2), when the content of each structural unit is within the above range, the adhesive layer and the cured temporary fixing material have improved light absorption in the ultraviolet region, so that the support can be more efficiently peeled off even when irradiated with low-energy laser light. Furthermore, since the adhesive layer and the temporary fixing material are more likely to harden by light irradiation, increased adhesion to the adherend during high-temperature processing can be further suppressed. As a result, the adhesive film and the cured temporary fixing material have improved releasability from the adherend, and can more effectively prevent adhesive residue from occurring when peeled from the adherend. Furthermore, the adhesive film and the cured temporary fixing material have better heat resistance. That is, the adhesive film and the cured temporary fixing material can more effectively prevent voids and lifting from occurring between the adhesive film and the support during high-temperature processing.Furthermore, the adhesive film and the cured temporary fixing material can further suppress increased adhesion to the adherend during high-temperature processing, thereby further improving the releasability to the adherend and further preventing the occurrence of adhesive residue when peeled from the adherend. Note that the structural unit represented by the above formula (1), the structural unit represented by the above formula (4-1), and the structural unit represented by the above formula (4-2) may have a block structure consisting of block components in which the respective structural units are arranged consecutively, or may have a random structure in which the respective structural units are arranged randomly.

[0071] Examples of methods for producing a resin having the above-mentioned functional group having a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain include the following. Specifically, first, a diamine compound is reacted with an aromatic acid anhydride to prepare an imide compound. Next, a compound having a functional group reactive with the functional group of the imide compound and a functional group having a carbon-carbon double bond (hereinafter also referred to as a "functional group-containing unsaturated compound") is reacted with the functional group of the imide compound to obtain a resin having the above-mentioned functional group having a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain. Alternatively, a resin having the above-mentioned functional group having a carbon-carbon double bond and an imide skeleton in the repeating unit of its main chain can also be obtained by reacting a diamine compound with an aromatic acid anhydride to prepare an imide compound, and then reacting the terminal of the imide compound with, for example, maleic anhydride.

[0072] The diamine compound and aromatic acid anhydride used in the method for producing a resin having a functional group with a carbon-carbon double bond and an imide skeleton in the repeating unit of the main chain may be the same as those used in the method for producing a resin not having a functional group with a carbon-carbon double bond and having an imide skeleton in the repeating unit of the main chain.

[0073] The functional group-containing unsaturated compound is selected and used depending on the functional group at the end or side chain of the imide compound.For example, when the functional group at the end or side chain of the imide compound is a hydroxyl group, the functional group-containing unsaturated compound may include a maleimide compound having a carboxyl group, a vinyl compound having an ether group, an allyl compound having a glycidyl group, an allyl ether compound having a glycidyl group, a vinyl ether compound having a glycidyl group, an allyl compound having an isocyanate group, a (meth)acryloyl compound having an isocyanate group, etc.Furthermore, when the functional group at the end or side chain of the imide compound is a carboxyl group, the functional group-containing unsaturated compound may include an allyl compound having a hydroxyl group, an allyl compound having a glycidyl group, an allyl ether compound having a glycidyl group, a vinyl ether compound having a glycidyl group, etc. Examples of the maleimide compound having a carboxy group include maleimide acetate, maleimidopropionic acid, maleimidobutyric acid, maleimidohexanoic acid, trans-4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid, 19-maleimido-17-oxo-4,7,10,13-tetraoxa-16-azanonadecanoic acid, etc. Examples of the vinyl compound having an ether group include butyl vinyl ether, etc. Examples of the allyl compound having a glycidyl group include diallyl monoglycidyl isocyanurate, etc. Examples of the allyl ether compound having a glycidyl group include allyl glycidyl ether, glycerin diallyl monoglycidyl ether, etc. Examples of the vinyl ether compound having a glycidyl group include glycidyloxyethyl vinyl ether, glycidyloxybutyl vinyl ether, glycidyloxyhexyl vinyl ether, glycidyl diethylene glycol vinyl ether, glycidyl cyclohexanedimethanol monovinyl ether, etc. Examples of the allyl compound having an isocyanate group include allyl isocyanate, etc. Examples of the (meth)acryloyl compound having an isocyanate group include 2-(meth)acryloyloxyethyl isocyanate, etc.Examples of the allyl compound having a hydroxyl group include trimethylolpropane diallyl ether and pentaerythritol triallyl ether.

[0074] The preferred lower limit of the content of the resin having a functional group with a carbon-carbon double bond and having an imide skeleton in the repeating unit of its main chain per 100 parts by mass of the curable resin is 10 parts by mass, and the preferred upper limit is 100 parts by mass. When the content of the resin having a functional group with a carbon-carbon double bond and having an imide skeleton in the repeating unit of its main chain is within this range, the adhesive film and the cured temporary fixing material can be more easily peeled off. From the viewpoint of further improving the peelability, the more preferred lower limit of the content of the resin having a functional group with a carbon-carbon double bond and having an imide skeleton in the repeating unit of its main chain is 20 parts by mass, even more preferably 30 parts by mass, and even more preferably 90 parts by mass, even more preferably 80 parts by mass, and even more preferably 70 parts by mass.

[0075] When the resin having an imide skeleton in the repeating unit of its main chain does not have the functional group having a carbon-carbon double bond and includes a resin having an imide skeleton in the repeating unit of its main chain, it is preferable that the curable resin further includes a polyfunctional monomer or polyfunctional oligomer (hereinafter simply referred to as a "polyfunctional monomer or polyfunctional oligomer") having two or more functional groups having a carbon-carbon double bond in the molecule and having a molecular weight of 5,000 or less. Also, when the resin having an imide skeleton in the repeating unit of its main chain includes the functional group having a carbon-carbon double bond and includes a resin having an imide skeleton in the repeating unit of its main chain, the curable resin may further include the polyfunctional monomer or polyfunctional oligomer. By including the polyfunctional monomer or polyfunctional oligomer, the adhesive layer and the temporary fixing material are more efficiently three-dimensionally reticulated by irradiation with light or the like, and the adhesion of the adhesive film and the hardened temporary fixing material to the adherend can be more effectively suppressed, thereby improving the releasability from the adherend and more effectively preventing adhesive residue from being left behind when peeled off.

[0076] In addition, when the resin having the imide skeleton in the repeating unit of the main chain is not reactive itself, the photocurable adhesive needs to be reactive as a whole by further containing another component having a reactive functional group. As such another component having a reactive functional group, it is preferable to use the polyfunctional monomer or polyfunctional oligomer. An example of a case where the resin having the imide skeleton in the repeating unit of the main chain is not reactive itself is when the resin having the imide skeleton in the repeating unit of the main chain does not have the functional group having the carbon-carbon double bond and only contains a resin having the imide skeleton in the repeating unit of the main chain.

[0077] Examples of the functional group having a carbon-carbon double bond in the polyfunctional monomer or polyfunctional oligomer include an optionally substituted maleimide group, a citraconic imide group, a vinyl ether group, an allyl group, and a (meth)acryloyl group. Among these, an optionally substituted maleimide group is preferred because it provides higher heat resistance. In particular, the polyfunctional monomer or polyfunctional oligomer is preferably a bismaleimide compound.

[0078] The polyfunctional monomer or polyfunctional oligomer preferably has a group derived from a diamine compound. As the diamine compound, either an aliphatic diamine compound or an aromatic diamine compound can be used, but an aliphatic diamine compound is preferred. That is, the polyfunctional monomer or polyfunctional oligomer more preferably has an aliphatic group derived from a diamine compound. By using an aliphatic diamine compound as the diamine compound, the adhesive film and the temporary fixing material have excellent flexibility, can exhibit high conformability to an adherend having irregularities, and can be more easily peeled off.

[0079] Among the above aliphatic diamine compounds, the above-mentioned dimer diamines are preferred from the viewpoints of flexibility and compatibility with the solvent of the polyfunctional monomer or polyfunctional oligomer and other components.

[0080] The preferred lower limit of the content of the polyfunctional monomer or polyfunctional oligomer per 100 parts by mass of the curable resin is 5 parts by mass, and the preferred upper limit is 90 parts by mass. When the content of the polyfunctional monomer or polyfunctional oligomer is within this range, the adhesive film and the cured temporary fixing material can be more easily peeled off. From the viewpoint of further improving peeling performance, the more preferred lower limit of the content of the polyfunctional monomer or polyfunctional oligomer is 10 parts by mass, and the more preferred upper limit is 50 parts by mass.

[0081] When the curable adhesive contains a resin that does not have the functional group having a carbon-carbon double bond and has an imide skeleton in its main chain repeating unit, a resin that has the functional group having a carbon-carbon double bond and has an imide skeleton in its main chain repeating unit, and the polyfunctional monomer or polyfunctional oligomer, the preferred lower limit of the total content of the resin that has the functional group having a carbon-carbon double bond and has an imide skeleton in its main chain repeating unit and the polyfunctional monomer or polyfunctional oligomer per 100 parts by mass of these combined is 20 parts by mass, and the preferred upper limit is 80 parts by mass. When the total content of the resin that has the functional group having a carbon-carbon double bond and has an imide skeleton in its main chain repeating unit and the polyfunctional monomer or polyfunctional oligomer is within this range, the adhesive film and the cured temporary fixing material can be more easily peeled off during peeling. From the viewpoint of further improving the release performance, the lower limit of the total content of the resin having a functional group with a carbon-carbon double bond and having an imide skeleton in the repeating unit of the main chain, and the polyfunctional monomer or polyfunctional oligomer is more preferably 30 parts by mass, even more preferably 40 parts by mass, still more preferably 50 parts by mass, and more preferably 70 parts by mass.

[0082] The curable resin preferably contains a compound having a maleimide group. By containing the compound having a maleimide group, the adhesive film and the cured temporary fixing material have excellent heat resistance. The compound having a maleimide group is preferably a bismaleimide compound, or a resin having a maleimide group and an imide skeleton in the repeating unit of its main chain. That is, the curable resin preferably contains the bismaleimide compound as the polyfunctional monomer or polyfunctional oligomer, or contains a resin having the functional group having a carbon-carbon double bond and having a maleimide group as the functional group having a carbon-carbon double bond of a resin having an imide skeleton in the repeating unit of its main chain.

[0083] The curable adhesive preferably further contains a polymerization initiator. By containing a polymerization initiator in the curable adhesive, the adhesive layer and the temporary fixing material are more easily cured, and the adhesive film and the cured temporary fixing material can be more effectively prevented from increasing their adhesion to the adherend during high-temperature processing, thereby improving the releasability from the adherend and making it easier to peel from the adherend. The polymerization initiator may be a thermal polymerization initiator or a photopolymerization initiator, with a photopolymerization initiator being preferred.

[0084] Examples of the photopolymerization initiator include those that are activated by irradiation with light having a wavelength of 250 to 800 nm. In the adhesive film of the present invention, the photopolymerization initiator preferably contains a compound having an absorption coefficient of 10 ml / (g cm) or more at a wavelength of 405 nm, since this is unlikely to overlap with the absorption wavelength of the resin having the imide skeleton in the main chain repeating unit or the polyfunctional monomer or polyfunctional oligomer, and is sufficiently activated when the adhesive layer is irradiated with light. The photopolymerization initiator more preferably contains a compound having an absorption coefficient of 50 ml / (g cm) or more at a wavelength of 405 nm, and even more preferably contains a compound having an absorption coefficient of 100 ml / (g cm) or more at a wavelength of 405 nm. There is no particular preferred upper limit to the molar absorption coefficient at a wavelength of 405 nm of the compound having a molar absorption coefficient of 1 or more at a wavelength of 405 nm, but a practical upper limit is 1.0 x 10 ６ ml / (g cm). In the temporary fixing material of the present invention, the photopolymerization initiator preferably contains a compound having a molar absorption coefficient at 405 nm of 1 or more, because the absorption wavelength is unlikely to overlap with that of the resin having the imide skeleton in the repeating unit of the main chain or the polyfunctional monomer or polyfunctional oligomer, and the temporary fixing material is sufficiently activated when irradiated with light. The photopolymerization initiator more preferably contains a compound having a molar absorption coefficient at 405 nm of 200 or more, and even more preferably contains a compound having a molar absorption coefficient at 405 nm of 350 or more. There is no particular preferred upper limit for the molar absorption coefficient at 405 nm of the compound having a molar absorption coefficient at 405 nm of 1 or more, but the substantial upper limit is 2000.

[0085] Examples of the photopolymerization initiator include acetophenone derivatives, benzoin ether compounds, ketal derivatives, phosphine oxide derivatives, and oxime ester compounds. Examples of the acetophenone derivatives include methoxyacetophenone, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, and 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)butan-1-one. Examples of the benzoin ether compounds include benzoin propyl ether and benzoin isobutyl ether. Examples of the ketal derivatives include benzyl dimethyl ketal and acetophenone diethyl ketal. Examples of the phosphine oxide derivatives include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide. Examples of the oxime ester compound include 1-(O-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone and 1-[4-(phenylthio)phenyl]-2-(O-benzoyloxime)-1,2-octadione. Examples of the photopolymerization initiator include bis(η5-cyclopentadienyl)titanocene derivative compounds, benzophenone, Michler's ketone, chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, α-hydroxycyclohexylphenyl ketone, and 2-hydroxymethylphenylpropane. These photopolymerization initiators may be used alone or in combination of two or more.

[0086] The preferred lower limit of the content of the polymerization initiator relative to 100 parts by mass of the curable resin is 0.1 parts by mass, and the preferred upper limit is 10 parts by mass. When the content of the polymerization initiator is within this range, the adhesive layer and the temporary fixing material are uniformly and quickly polymerized and crosslinked as a whole by light irradiation, heating, etc., and the elastic modulus increases, significantly reducing the adhesive strength of the resulting adhesive film and the temporary fixing material, thereby more effectively preventing increased adhesion and the generation of adhesive residue upon peeling. The more preferred lower limit of the content of the polymerization initiator is 0.5 parts by mass, and even more preferred is 1 part by mass, and the more preferred upper limit is 7 parts by mass, and even more preferred is 5 parts by mass.

[0087] In the adhesive film of the present invention, when the curable adhesive contains the photopolymerization initiator, it is preferable that the curable adhesive further contains an ultraviolet absorber. By containing an ultraviolet absorber in the curable adhesive, the adhesive layer has a higher absorbency in the ultraviolet region, and therefore the support can be peeled off more efficiently even when irradiated with low-energy laser light.

[0088] The curable adhesive preferably contains an ultraviolet absorber or an ultraviolet scattering agent. When the curable adhesive contains an ultraviolet absorber, the cured temporary fixing material has better ultraviolet absorption properties, which further improves its laser processing resistance and allows the support to be peeled off more efficiently. When the curable adhesive contains an ultraviolet scattering agent, the laser processing resistance of the surface of the cured temporary fixing material is further improved and allows the support to be peeled off more efficiently. Furthermore, the curable adhesive may contain both an ultraviolet absorber and an ultraviolet scattering agent.

[0089] Examples of the ultraviolet absorber in the adhesive film of the present invention include triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, salicylate-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers, etc. Among these, from the viewpoint of heat resistance, it is preferable that the ultraviolet absorber contains a triazine-based ultraviolet absorber.

[0090] In the temporary fixing material of the present invention, examples of the ultraviolet absorber include triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, salicylate-based ultraviolet absorbers, and cyanoacrylate-based ultraviolet absorbers. Examples of the ultraviolet scattering agent include titanium oxide and zinc oxide. Among these, from the viewpoint of heat resistance, it is preferable that the ultraviolet absorber or the ultraviolet scattering agent contains a triazine-based ultraviolet absorber or titanium oxide.

[0091] Examples of the triazine-based ultraviolet absorber include Tinuvin 400, Tinuvin 405, Tinuvin 460, Tinuvin 477, Tinuvin 479, Tinuvin 1577ED, and Tinuvin 1600 (all manufactured by BASF Corporation), and Adekastab LA46 and Adekastab LA-F70 (all manufactured by ADEKA Corporation). Of these, Tinuvin 400, Tinuvin 479, and Tinuvin 1600 are preferred.

[0092] The preferred lower limit of the content of the ultraviolet absorber or ultraviolet scattering agent relative to 100 parts by mass of the curable resin is 1 part by mass, and the preferred upper limit is 30 parts by mass. If the content of the ultraviolet absorber or ultraviolet scattering agent is 1 part by mass or more, the adhesive layer and the cured temporary fixing material will have higher absorbency in the ultraviolet region, thereby enabling more efficient peeling of the support even when irradiated with low-energy laser light. If the content of the ultraviolet absorber or ultraviolet scattering agent is 30 parts by mass or less, the adhesive film and the cured temporary fixing material will be easily peelable from the adherend even after the heating step. The preferred lower limit of the ultraviolet absorber or ultraviolet scattering agent is 5 parts by mass, and even more preferred is 7 parts by mass, with a more preferred upper limit of 20 parts by mass and an even more preferred upper limit of 15 parts by mass.

[0093] The photocurable adhesive preferably further contains a release agent. Examples of the release agent include silicone-based release agents, fluorine-based release agents, and acrylic-based release agents. These release agents have excellent heat resistance, so by including a release agent in the curable adhesive, the adhesive layer is prevented from burning even after high-temperature processing at 300°C or higher, and the resulting adhesive film bleeds out to the adherend interface when peeled, making peeling easier. Among these, silicone-based release agents are preferred from the standpoint of environmental friendliness and ease of disposal. Acrylic release agents are also preferred from the standpoint of preventing silicone contamination of the adherend.

[0094] The release agent may have a functional group capable of crosslinking with a resin having the imide skeleton in its main chain repeating unit. When the release agent has a functional group capable of crosslinking with a resin having the imide skeleton in its main chain repeating unit, the release agent chemically reacts with the resin having the imide skeleton in its main chain repeating unit or the polyfunctional monomer or polyfunctional oligomer upon irradiation with light or reaction with a crosslinking agent, etc., and is incorporated into the resin. This prevents the release agent from adhering to and contaminating the adherend. Examples of functional groups capable of crosslinking with the resin having the imide skeleton in its main chain repeating unit or the polyfunctional monomer or polyfunctional oligomer include a carboxy group, a functional group having a radically polymerizable unsaturated bond (e.g., a vinyl group, a (meth)acryloyl group, or an optionally substituted maleimide group), a hydroxy group, an amide group, an isocyanate group, and an epoxy group.

[0095] Examples of the silicone-based release agent include silicone oil, silicone diacrylate, and silicone-based graft copolymer. Specifically, a silicone compound having a siloxane skeleton in the main chain and a functional group having a carbon-carbon double bond in a side chain or at a terminal is preferred. As the silicone compound having a siloxane skeleton in the main chain and a functional group having a carbon-carbon double bond in a side chain or at a terminal, at least one selected from the group consisting of a silicone compound represented by the following formula (5-1), a silicone compound represented by the following formula (5-2), and a silicone compound represented by the following formula (5-3) is preferred. These silicone compounds are particularly excellent in heat resistance and have high polarity, so they easily bleed out from the adhesive film and the temporary fixing material.

[0096]

[0097] X in the above formulas (5-1) to (5-3) and Y in the above formulas (5-1) and (5-3) each independently represent an integer of 0 or more and 1200 or less, and R in the above formulas (5-1) to (5-3) represents a functional group having a carbon-carbon double bond.

[0098] In the above formulas (5-1) to (5-3), examples of the functional group having a carbon-carbon double bond represented by R include an optionally substituted maleimide group, a citraconic imide group, a vinyl ether group, an allyl group, and a (meth)acryloyl group. Among these, an optionally substituted maleimide group is preferred because it provides the adhesive film and the temporary fixing material with superior heat resistance. Note that when there are multiple R in the above formulas (5-1) to (5-3), the respective R may be the same or different.

[0099] Among the silicone compounds represented by the above formulas (5-1) to (5-3), commercially available examples include EBECRYL350 and EBECRYL1360 (both manufactured by Daicel-Allnex Co., Ltd.), etc. Other examples include BYK-UV3500 (manufactured by BYK-Chemie Co., Ltd.) and TEGO RAD2250 (manufactured by Evonik Co., Ltd.) (in both cases, R is an acryloyl group).

[0100] Examples of the fluorine-based release agent include hydrocarbon compounds containing fluorine atoms.

[0101] Examples of the acrylic release agent include BYK-394, BYK-350, and BYK-381 (all manufactured by BYK-Chemie), and Disparlon 1970 (manufactured by Kusumoto Chemicals Co., Ltd.).

[0102] The content of the release agent is preferably 0.1 parts by mass at its lower limit and 20 parts by mass at its upper limit relative to 100 parts by mass of the curable resin. When the content of the release agent is within this range, the adhesive film and the temporary fixing material after curing do not contaminate the adherend and exhibit excellent release performance. From the viewpoint of further enhancing release performance while suppressing contamination, the lower limit of the content of the release agent is more preferably 0.3 parts by mass and the upper limit is more preferably 10 parts by mass.

[0103] The curable adhesive may further contain a gas-generating agent. By containing a gas-generating agent in the curable adhesive, even after high-temperature processing at 300°C or higher, gas generated by irradiation with light or the like is released at the interface with the adherend, making it possible to peel the adhesive film and the temporary fixing material from the adherend more easily and without leaving any adhesive residue. Furthermore, even when peeling a thin adherend after high-temperature processing at 300°C or higher, damage to the adherend can be prevented.

[0104] The gas generating agent preferably has a weight loss rate of 5% or less when heated from 30°C to 300°C at a temperature increase rate of 10°C / min in a nitrogen atmosphere in TG-DTA (thermogravimetry-differential thermal analysis) measurement. If the weight loss rate is 5% or less, decomposition of the gas generating agent is unlikely to occur even when high-temperature processing is performed at 300°C or higher, and the adhesive film and the cured temporary fixing material have superior heat resistance. In other words, peeling during high-temperature processing can be further suppressed, and enhanced adhesion and the occurrence of adhesive residue upon peeling can be further prevented. The TG-DTA (thermogravimetry-differential thermal analysis) measurement can be performed using, for example, a TG-DTA device ("STA7200RV" manufactured by Hitachi High-Tech Science Corporation).

[0105] Examples of the gas generating agent include a gas generating agent that generates gas by heating and a gas generating agent that generates gas by irradiating with light. Among these, a gas generating agent that generates gas by irradiating with light is preferred, and a gas generating agent that generates gas by irradiating with ultraviolet light is more preferred. Examples of the gas generating agent include a tetrazole compound or a salt thereof, a triazole compound or a salt thereof, an azo compound, an azide compound, xanthone acetate, a carbonate, and the like. These gas generating agents may be used alone or in combination of two or more. Among these, a tetrazole compound or a salt thereof is preferred because of its particularly excellent heat resistance.

[0106] The content of the gas generating agent is preferably 5 parts by mass or less and 50 parts by mass or less per 100 parts by mass of the curable resin. When the content of the gas generating agent is within this range, the adhesive film and the cured temporary fixing material have particularly excellent release performance. The more preferred lower limit of the content of the gas generating agent is 8 parts by mass, and the more preferred upper limit is 30 parts by mass.

[0107] The photocurable adhesive may further contain an inorganic filler. By containing the inorganic filler, the adhesive layer and the temporary fixing material can be prevented from decreasing in elastic modulus at high temperatures, and the adhesive film and the cured temporary fixing material can be further prevented from peeling off during high-temperature processing, even when high-temperature processing is performed at 300°C or higher.

[0108] Examples of the inorganic filler include inorganic fillers consisting of at least one selected from the group consisting of oxides of silicon, aluminum, calcium, boron, magnesium, and zirconia, and composites thereof. Among these, silica and talc are preferred because they are commercially available at low cost and easily available.

[0109] The inorganic filler may be surface-modified. Examples of the functional group that may be used to modify the surface of the inorganic filler include an alkylsilane group, a methacryloyl group, and a dimethylsiloxane group. Among these, a dimethylsiloxane group is preferred because it has appropriate hydrophobicity.

[0110] The preferred lower limit of the average particle size of the inorganic filler is 5 nm, and the preferred upper limit is 30 μm. By having the average particle size of the inorganic filler within this range, the adhesive film and the cured temporary fixing material can be more effectively prevented from peeling during high-temperature processing, and can be peeled off by peel treatment. The more preferred lower limit of the average particle size of the inorganic filler is 10 nm, and even more preferred is 15 nm, and the more preferred upper limit is 20 μm, and even more preferred is 15 μm. The average particle size can be determined, for example, by observing 50 particles of any inorganic filler using an electron microscope or optical microscope, calculating the average particle size of each inorganic filler, or by performing laser diffraction particle size distribution measurement.

[0111] The content of the inorganic filler is preferably 1 part by mass at the lower limit and 20 parts by mass at the upper limit relative to 100 parts by mass of the curable resin. By having the content of the inorganic filler within this range, peeling of the adhesive film and the cured temporary fixing material during high-temperature processing can be further suppressed, and they can be peeled off by peel treatment. The lower limit of the content of the inorganic filler is more preferably 3 parts by mass, even more preferably 5 parts by mass, and the upper limit is more preferably 15 parts by mass, even more preferably 10 parts by mass.

[0112] The curable adhesive may contain known additives such as photosensitizers, heat stabilizers, antioxidants, antistatic agents, plasticizers, resins, surfactants, and waxes.

[0113] The adhesive film of the present invention may or may not have a substrate. When the substrate is not included, there is no need to select a substrate having both optical transparency and heat resistance, and the adhesive film of the present invention can be constructed more inexpensively and simply. When the substrate is included, the adhesive film of the present invention is more easily handled. Furthermore, the adhesive film of the present invention is preferably in a tape form from the viewpoint of handleability. When the substrate is included, the adhesive film of the present invention may have the photocurable adhesive on one or both surfaces of the substrate. Examples of the substrate include resin sheets made of acrylic, olefin, polycarbonate, vinyl chloride, ABS, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), nylon, urethane, polyimide, polyether ether ketone (PEEK), polyamide (PA), etc., and resin sheets with high optical transparency are preferably used. Furthermore, sheets with a mesh structure, perforated sheets, glass, etc. can also be used. From the viewpoint of enhancing flexibility, the lower limit of the thickness of the substrate is preferably 5 μm, more preferably 10 μm, and the upper limit is preferably 150 μm, more preferably 100 μm.

[0114] The temporary fixing material of the present invention may be in a liquid or paste form, or may be in the form of a tape having an adhesive layer containing a curable adhesive, preferably a tape-like temporary fixing material. In this case, the tape may have the adhesive layer on one or both surfaces of the substrate, or may not have a substrate. If the tape does not have a substrate, there is no need to select a substrate that has both light transparency and heat resistance, and the tape can be made more inexpensively and simply. If the tape has a substrate, the handleability of the temporary fixing material of the present invention is further improved. If the substrate is used, examples of the substrate include resin sheets made of acrylic, olefin, polycarbonate, vinyl chloride, ABS, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), nylon, urethane, polyimide, polyether ether ketone (PEEK), polyamide (PA), etc., and resin sheets with high light transparency are preferably used. Furthermore, sheets with a mesh structure, perforated sheets, glass, etc. can also be used. From the viewpoint of enhancing flexibility, the lower limit of the thickness of the substrate is preferably 5 μm, more preferably 10 μm, and the upper limit is preferably 150 μm, more preferably 100 μm.

[0115] The method for producing the adhesive film of the present invention is not particularly limited, and it can be produced by a conventionally known method. Specifically, for example, the resin having the imide skeleton as a repeating unit of the main chain and additives to be added as needed are first mixed using a bead mill, ultrasonic dispersion, homogenizer, high-power disperser, roll mill, etc. to prepare the curable adhesive. Next, the prepared curable adhesive is applied with a doctor knife to the release-treated surface of a 50 μm-thick release polyethylene terephthalate (PET) film that has been release-treated on one side, and the coating solution is dried by heating at 130° C. for 10 minutes to form an adhesive layer. After that, a 50 μm-thick release PET film is overlaid so that the release-treated surface faces the adhesive layer, thereby obtaining the adhesive film. Furthermore, when the adhesive film of the present invention has a substrate, the prepared curable adhesive can be applied with a doctor knife to the release-treated surface of a 50 μm-thick release polyethylene terephthalate (PET) film that has been release-treated on one side, and the coating solution is dried by heating at 130°C for 10 minutes to produce a laminated film with an adhesive layer formed thereon, and the adhesive layer of the laminated film can be superimposed on the surface of the substrate layer.

[0116] As a method for producing the temporary fixing material, for example, when the temporary fixing material is in a liquid or paste form, a method can be mentioned in which the resin having the imide skeleton in the repeating unit of the main chain and additives to be blended as necessary are mixed using a bead mill, ultrasonic dispersion, a homogenizer, a high-power disperser, a roll mill, etc. Furthermore, when the temporary fixing material is in the form of a tape or the like having an adhesive layer containing a curable adhesive, it can be produced by the same method as the adhesive film described above.

[0117] The adhesive film of the present invention preferably has a lower limit of 5 μm and an upper limit of 550 μm in total thickness (when a substrate is present, the total thickness of the adhesive layer and the substrate). When the adhesive film of the present invention has a total thickness of 5 μm or more, it can have sufficient pressure-sensitive or heat-sensitive adhesive strength initially. When the adhesive film of the present invention has a total thickness of 550 μm or less, it can exhibit high flexibility, can exhibit high conformability to an adherend having irregularities, and can be more easily peeled off. The adhesive film of the present invention more preferably has a lower limit of 10 μm, even more preferably 20 μm, and a more preferably upper limit of 400 μm, even more preferably 300 μm.

[0118] The adhesive film of the present invention is resistant to light with a wavelength of 405 nm with an integrated light intensity of 20,000 mJ / cm ２ The preferred lower limit of the 5% weight loss temperature when heated in a nitrogen atmosphere at a heating rate of 10°C / min after irradiation (hereinafter sometimes simply referred to as "5% weight loss temperature when heated in a nitrogen atmosphere at a heating rate of 10°C / min after light irradiation") is 300°C. If the 5% weight loss temperature of the adhesive film of the present invention when heated in a nitrogen atmosphere at a heating rate of 10°C / min after light irradiation is 300°C or higher, the resulting adhesive film will have better heat resistance and will be able to better suppress peeling during high-temperature processing. A more preferred lower limit of the 5% weight loss temperature of the adhesive film of the present invention when heated in a nitrogen atmosphere at a heating rate of 10°C / min after light irradiation is 350°C, and an even more preferred lower limit is 375°C. Furthermore, there is no particular preferred upper limit of the 5% weight loss temperature of the adhesive film of the present invention when heated in a nitrogen atmosphere at a heating rate of 10°C / min after light irradiation, but the substantial upper limit is 600°C. The 5% weight loss temperature when the adhesive film of the present invention is heated at a temperature increase rate of 10°C / min in a nitrogen atmosphere after light irradiation can be measured by TG-DTA (thermogravimetry-differential thermal analysis) using, for example, a TG-DTA device ("STA7200RV" manufactured by Hitachi High-Tech Science Corporation).

[0119] The temporary fixing material of the present invention preferably has a weight loss rate of 7% or less when heated at 290°C for 30 minutes in a nitrogen atmosphere after curing. If the weight loss rate is 7% or less, the temporary fixing material after curing has excellent heat resistance and is more likely to peel off during high-temperature processing. A more preferred upper limit of the weight loss rate is 5%, and an even more preferred upper limit is 3%. There is no particular preferred lower limit for the weight loss rate, but the substantial lower limit is 0.01%. The weight loss rate when heated at 290°C for 30 minutes in a nitrogen atmosphere can be measured by TG-DTA (thermogravimetry-differential thermal analysis) using a TG-DTA device ("STA7200RV" manufactured by Hitachi High-Tech Science Corporation), for example.

[0120] The preferred lower limit of the UV absorbance of the temporary fixing material of the present invention after curing is 80%. If the UV absorbance is 80% or higher, the temporary fixing material after curing will have better UV absorbance, further improving its laser processing performance and allowing for more efficient peeling of the support. Furthermore, the peeling performance of the temporary fixing material after curing is further improved, and adhesive residue of the temporary fixing material after curing can be further reduced. The preferred lower limit of the UV absorbance is 90%, and a more preferred lower limit is 95%. There is no particular preferred upper limit for the UV absorbance, but the practical upper limit is 100%. The UV absorbance can be measured using a spectrophotometer. The optical path length in this case is the thickness of the temporary fixing material after curing. Examples of the spectrophotometer include the U-3900 (manufactured by Hitachi High-Tech Science Corporation).

[0121] The preferred lower limit of the gel fraction of the temporary fixing material of the present invention after curing is 50% by mass, and the preferred upper limit is 99% by mass. When the gel fraction of the temporary fixing material after curing is within the above range, the material can be more easily peeled from the adherend. A more preferred lower limit of the gel fraction of the cured product is 60% by mass, and a more preferred upper limit is 95% by mass. The gel fraction of the temporary fixing material after curing is measured, for example, by the following method. That is, the temporary fixing material after curing is heated to a temperature of 1000°C (W ０(g) The hardened temporary fixing material is collected and immersed in toluene at 23°C for 24 hours. After shaking, the temporary fixing material is passed through a metal mesh (opening #200 mesh, mass: W １ (g)), the hardened temporary fixing material that has absorbed toluene and swelled is filtered, and the separated hardened temporary fixing material is dried at 110°C for 1 hour. The mass W of the hardened temporary fixing material after drying is ２ The gel fraction of the cured temporary fixing material can be measured by measuring the mass (g) and calculating the gel fraction using the following formula: Gel fraction (mass%) = 100 × (W ２ -W １ ) / W ０ (W ０ : Mass of temporary fixing material after initial hardening, W １ : initial mass of the metal mesh, W ２ : Mass of temporary fixing material after hardening including metal mesh after drying)

[0122] When the temporary fixing material of the present invention is not in a liquid or paste form (for example, in the case of a tape-like temporary fixing material), the preferred lower limit of the thickness after curing is 5 μm, and the preferred upper limit is 550 μm. When the thickness of the temporary fixing material after curing is 5 μm or more, the temporary fixing material can initially have sufficient pressure-sensitive or heat-sensitive adhesive strength. When the thickness of the temporary fixing material after curing is 550 μm or less, the temporary fixing material can exhibit high flexibility even after curing, exhibit high conformability to an adherend having irregularities, and can be more easily peeled off. The more preferred lower limit of the thickness of the temporary fixing material after curing is 10 μm, even more preferred is 20 μm, and even more preferred is 30 μm. The more preferred upper limit of the thickness of the temporary fixing material after curing is 400 μm, even more preferred is 300 μm, even more preferred is 200 μm, and particularly preferred is 150 μm.

[0123] The adhesive film of the present invention can be easily peeled from the support even when irradiated with low-energy laser light, and can also be easily peeled from the adherend even when subjected to high-temperature processing. Therefore, the adhesive film of the present invention can be suitably used in the manufacture of electronic components that involve a support peeling step or a high-temperature processing step by irradiation with laser light. In particular, it can be suitably used for temporary fixing of electronic components in the manufacture of electronic components such as semiconductor devices.

[0124] The temporary fixing material of the present invention has suitable laser processing resistance, so that the support can be easily peeled off even when irradiated with a low-energy laser beam after curing. Therefore, the temporary fixing material of the present invention can be suitably used in the manufacture of electronic components that involve a support peeling step by irradiating with laser beam. In particular, the temporary fixing material of the present invention can be suitably used in the manufacture of semiconductor devices.

[0125] The adhesive film of the present invention or a cured product obtained by curing the temporary fixing material of the present invention also constitutes one aspect of the present invention. The cured product of the present invention has suitable processability, allowing the support to be easily peeled off even when irradiated with low-energy laser light. Therefore, the cured product can be suitably used in the manufacture of electronic components that involve a support peeling step by irradiation with laser light. In particular, the cured product can be suitably used in the manufacture of semiconductor devices.

[0126] The cured product of the present invention may be a temporary fixing material in a liquid or paste form or a temporary fixing material in an adhesive film or tape form, and is preferably a temporary fixing material in an adhesive film or tape form. When the adhesive film or the temporary fixing material has photocurability, the cured product can be obtained by, for example, irradiating the temporary fixing material with ultraviolet light at a wavelength of 365 nm with an integrated light intensity of 20,000 mJ / cm. ２ When the adhesive film or the temporary fixing material is thermosetting, the cured product can be obtained by curing the temporary fixing material, for example, by heating the temporary fixing material in a nitrogen atmosphere at 290°C for 30 minutes.

[0127] The cured product obtained by curing the adhesive film was exposed to radiation at a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm ２ The preferred lower limit of the laser processing depth when the cured product is irradiated with pulsed laser light having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is 0.10 μm. ２ The laser processing depth when pulsed with a laser beam of 308 nm wavelength, 10 nsec pulse width, and 300 mJ / cm irradiated with the cured product is 0.10 μm or more, so that the cured product can be peeled off from the support more efficiently even when irradiated with a low-energy laser beam. ２ The lower limit of the laser processing depth when pulsed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is more preferably 0.15 μm, and even more preferably 0.20 μm. ２ The lower limit of the laser processing depth when pulsed irradiated with a laser beam of 308 nm wavelength, 10 nsec pulse width, and 300 mJ / cm irradiated energy density is preferably within the above range on at least one surface of the cured product, and more preferably within the above range on both surfaces of the cured product. ２ The lower limit of the laser processing depth when the above cured product is irradiated with pulsed laser light of wavelength 308 nm, pulse width 10 nsec, and irradiation energy density 300 mJ / cm ２ The laser processing depth when pulsed with a laser beam of 308 nm wavelength, 10 nsec pulse width, and 300 mJ / cm irradiated with the cured product is 0.10 μm or more, so that the cured product can be efficiently peeled off from the support even when irradiated with a low-energy laser beam. ２The preferred lower limit of the laser processing depth when pulsed irradiation with a laser beam of 308 nm wavelength, 10 nsec pulse width, and 300 mJ / cm irradiated is 0.15 μm, and the more preferred lower limit is 0.20 μm. ２ The lower limit of the laser processing depth when pulsed irradiation with the laser light of the above range should be satisfied on at least one surface of the cured product, but it is preferable that the range be satisfied on both surfaces of the cured product.

[0128] The above cured product was exposed to light with a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm ２ The preferred upper limit of the laser processing depth when pulsed irradiation is performed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm is 1.0 μm. ２ When the laser processing depth is 1.0 μm or less when pulsed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm, the temporary fixing material after hardening has improved laser processing resistance, and the support can be peeled off more efficiently. ２ The upper limit of the laser processing depth when pulsed irradiation with the laser light of wavelength 308 nm, pulse width 10 nsec, and irradiation energy density 300 mJ / cm is more preferably 0.80 μm, and even more preferably 0.60 μm. ２ The upper limit of the laser processing depth when pulsed irradiation of the laser light is performed preferably satisfies the above range on at least one surface of the cured product, and more preferably satisfies the above range on both surfaces of the cured product.

[0129] The cured product was exposed to radiation at a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm ２ The preferred upper limit of the laser processing depth when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is 1.0 μm. ２When the laser processing depth is 1.0 μm or less when pulsed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm, the laser processing performance of the cured product is further improved, and the support can be peeled off more efficiently. ２ The upper limit of the laser processing depth when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is more preferably 0.80 μm, and even more preferably 0.60 μm. ２ The preferred lower limit of the laser processing depth when pulsed irradiation is performed with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is 0.10 μm. ２ When the laser processing depth is 0.10 μm or more when pulsed irradiation with a laser beam having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 400 mJ / cm is performed, the laser processing performance of the cured film is further improved, and the support can be peeled off more efficiently. ２ When the cured product is not a liquid or paste-like temporary fixing material, the lower limit of the laser processing depth when pulsed irradiation with the laser light of wavelength 308 nm, pulse width 10 nsec, and irradiation energy density 400 mJ / cm is more preferably 0.15 μm, and even more preferably 0.20 μm. ２ The laser processing depth when pulsed with the laser light preferably satisfies the above range on at least one surface of the cured product, and more preferably satisfies the above range on both surfaces of the cured product.

[0130] The adhesive film of the present invention is preferably used in a laminate having a support, the adhesive film of the present invention, and a semiconductor device in this order. When the adhesive film of the present invention is used in a laminate having the above-mentioned configuration, it can be used more suitably in the manufacture of electronic components. A laminate having a support, the adhesive film of the present invention, and a semiconductor device in this order (hereinafter sometimes referred to as "laminate (a)") also constitutes one aspect of the present invention.

[0131] The cured product of the temporary fixing material of the present invention is preferably used in a laminate having a support, the cured product, and a semiconductor device in this order. When used in a laminate having the above configuration, the cured product of the temporary fixing material of the present invention can more efficiently peel off the support even when irradiated with low-energy laser light, and therefore can be suitably used in the manufacture of electronic components. A laminate (hereinafter sometimes referred to as "laminate (b)") having a support, a cured product of the temporary fixing material of the present invention, and a semiconductor device in this order, wherein the support has a transmittance of 50% or more for light at a wavelength of 300 nm or more and 400 nm or less, also constitutes one aspect of the present invention.

[0132] Hereinafter, matters common to the laminate (a) and the laminate (b) will not be specified, or will be simply referred to as "the laminate."

[0133] The material of the support is preferably a material with high light transmittance, such as glass, quartz, or sapphire.

[0134] In the laminate (a), the preferred lower limit of the transmittance of the support at a wavelength of 200 nm or more and 355 nm or less is 20%. If the transmittance of the support at a wavelength of 200 nm or more and 355 nm or less is 20% or more, the support can be efficiently peeled from the adhesive film. A more preferred lower limit of the transmittance of the support at a wavelength of 200 nm or more and 355 nm or less is 30%, and an even more preferred lower limit is 50%. There is no particular preferred upper limit of the transmittance of the support at a wavelength of 200 nm or more and 355 nm or less, but the substantial upper limit is 95%.

[0135] In the laminate (b), the preferred lower limit of the transmittance of the support at a wavelength of 300 nm to 400 nm is 50%. If the transmittance of the support at a wavelength of 300 nm to 400 nm is 50% or more, the laser processing performance of the cured product is further improved, and the support can be peeled off more efficiently. A more preferred lower limit of the transmittance of the support at a wavelength of 300 nm to 400 nm is 60%, and an even more preferred lower limit is 70%. In addition, there is no particular preferred upper limit of the transmittance of the support at a wavelength of 300 nm to 400 nm, but the substantial upper limit is 95%.

[0136] The upper limit of the haze of the support is not particularly limited, but from the viewpoint of irradiating the adhesive film or the cured product of the temporary fixing material with laser light from the support side, it is preferable that the haze of the support is small. The preferred upper limit of the haze of the support is 10%, and more preferably 5%. There is no particular preferred lower limit of the haze of the support, but the substantial lower limit is 0.001%. The haze of the support can be measured, for example, using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., "NDH4000") or the like.

[0137] The laminate (a) may have the support, the adhesive film of the present invention, and the semiconductor device in this order, as described above, and may further have other layers as long as the effects of the present invention are not impaired. The laminate (b) may have the support, the cured product of the temporary fixing material, and the semiconductor device in this order, as described above, and may further have other layers as long as the effects of the present invention are not impaired.

[0138] The present invention also provides a method for producing an electronic component, comprising: a light irradiation step of irradiating the laminate (a) from the support side with light; a high-temperature processing step of subjecting the laminate to a heat treatment or a heat-generating treatment; a support peeling step of irradiating the laminate (a) from the support side with laser light having a wavelength of 200 nm or more and 355 nm or less to peel the support from the adhesive film (hereinafter sometimes referred to as the "support peeling step (a)"); and an adhesive film peeling step of peeling the adhesive film from the semiconductor device. The method for producing an electronic component of the present invention can efficiently peel the support from the adhesive film even when irradiating low-energy laser light, and can efficiently peel the adhesive film from the semiconductor device even when high-temperature processing is performed. As a result, electronic components can be produced without reducing the processing quality of the electronic component due to factors such as carbonization of the adhesive film, damage to the support, contamination of the adhesive film or support, deterioration of the support's peeling performance, and adhesive residue when the adhesive film is peeled.

[0139] Examples of the light source used in the light irradiation step include an ultra-high pressure mercury lamp, an LED, etc. Among these, an ultra-high pressure mercury lamp is preferred from the viewpoint of facilitating curing of the photocurable adhesive.

[0140] The wavelength of the light irradiated in the light irradiation step is preferably 356 nm at the lower limit and 500 nm at the upper limit. When the wavelength of the light irradiated in the light irradiation step is within the above range, the adhesive film is photocured more efficiently in the light irradiation step, and the adhesive film can be easily peeled off in the adhesive film peeling step. Furthermore, in the support peeling step, the support can be more efficiently peeled off from the adhesive film using laser light having a wavelength in the range described below. The wavelength of the light irradiated in the light irradiation step is more preferably 360 nm at the lower limit, even more preferably 375 nm at the lower limit, and more preferably 450 nm at the upper limit, even more preferably 420 nm at the upper limit.

[0141] The preferred lower limit of the cumulative light amount of the light irradiated in the light irradiation step is 1000 mJ / cm ２ and the preferred upper limit is 30,000 mJ / cm ２The integrated light amount of the light irradiated in the light irradiation step is 1000 mJ / cm ２ By irradiating the adhesive film so that the cumulative light amount of the light irradiated in the light irradiation step is 30,000 mJ / cm or more, the adhesive film can be cured more sufficiently. ２ By irradiating the light so that the integrated light amount of the light irradiated in the light irradiation step is 3000 mJ / cm or less, the photodecomposition of the low molecular weight compound can be suppressed, and the high temperature processing step can be applied to a higher temperature. ２ , and a more preferable lower limit is 5000 mJ / cm ２ and a more preferable upper limit is 25000 mJ / cm ２ , and a more preferable upper limit is 20,000 mJ / cm ２ is.

[0142] Examples of the high-temperature processing step include reflow, sputtering, thermocompression bonding (TCB), and the like.

[0143] The wavelength of the laser light irradiated in the support peeling step (a) is preferably 200 nm at its lower limit and 355 nm at its upper limit. When the wavelength of the laser light irradiated in the support peeling step (a) is within the above range, the support can be more efficiently peeled from the adhesive film while further suppressing damage to the support.

[0144] The preferred upper limit of the irradiation energy density of the laser light irradiated in the support peeling step (a) is 500 mJ / cm ２ The irradiation energy density of the laser light irradiated in the support peeling step (a) is 500 mJ / cm ２ If the irradiation energy density of the laser beam irradiated in the support peeling step (a) is 400 mJ / cm or less, the support can be more efficiently peeled from the adhesive film while further suppressing damage to the support. ２ , and a more preferable upper limit is 300 mJ / cm ２ Although there is no preferred lower limit to the irradiation energy density of the laser light irradiated in the support peeling step (a), the substantial lower limit is 100 mJ / cm ２ is.

[0145] The laser light irradiated in the support peeling step (a) may be a CW (Continuous Wave) laser or a pulsed laser.

[0146] When the laser light irradiated in the support peeling step (a) is a pulsed laser, the preferred upper limit of the pulse width is 100 nsec. If the pulse width of the laser light irradiated in the support peeling step (a) is 100 nsec or less, the support can be more efficiently peeled from the adhesive film while further suppressing damage to the support. A more preferred upper limit of the pulse width of the laser light irradiated in the support peeling step (a) is 50 nsec, and an even more preferred upper limit is 20 nsec. There is no particular preferred lower limit for the pulse width of the laser light irradiated in the support peeling step (a), but the substantial lower limit is 5 fsec.

[0147] A laminate including a support, a cured product of the temporary fixing material, and a semiconductor device in this order is irradiated with a wavelength of 308 nm or more and 355 nm or less, a pulse width of 100 nsec or less, and an irradiation energy density of 500 mJ / cm ２ The present invention also includes a method for producing an electronic component, which includes a support peeling step (hereinafter, also referred to as a "support peeling step (b)") of peeling the support from the laminate by pulse-irradiating the support with the following laser light from the support side: The method for producing an electronic component of the present invention includes irradiating a laminate including a support, a cured product of a temporary fixing material, and a semiconductor device in this order with a laser beam having a wavelength of 308 nm or more and 355 nm or less, a pulse width of 100 nsec or less, and an irradiation energy density of 500 mJ / cm. ２ The manufacturing method includes a support peeling step of irradiating the support with pulsed laser light from the support side to peel off the support. By including the support peeling step (b), the support can be peeled off efficiently even when a low-energy laser is irradiated, and electronic components can be manufactured without deteriorating the processing quality of the electronic components due to carbonization of the temporary fixing material, damage to the support, contamination of the temporary fixing material or the support, deterioration of the support peeling performance, etc.

[0148] In the method for producing an electronic component of the present invention, a laminate similar to the above-described laminate including a support, a cured product of a temporary fixing material, and a semiconductor device in this order is preferably used.

[0149] The wavelength of the laser light irradiated in the support peeling step (b) has a lower limit of 308 nm and an upper limit of 355 nm. When the wavelength of the laser light irradiated in the support peeling step (b) is within the above range, the laser processing performance of the cured product is improved, and the support can be peeled off efficiently.

[0150] The upper limit of the pulse width of the laser light irradiated in the support peeling step (b) is 100 nsec. If the pulse width of the laser light irradiated in the support peeling step (b) is 100 nsec or less, the laser processing performance of the cured product is improved, and the support can be efficiently peeled while suppressing damage to the support. The preferred upper limit of the pulse width of the laser light irradiated in the support peeling step (b) is 50 nsec, and the more preferred upper limit is 20 nsec. There is no particular preferred lower limit of the pulse width of the laser light irradiated in the support peeling step (b), but the substantial lower limit is 50 fsec.

[0151] The upper limit of the irradiation energy density of the laser light irradiated in the support peeling step (b) is 500 mJ / cm ２ The irradiation energy density of the laser light irradiated in the support peeling step (b) is 500 mJ / cm ２ If the laser beam irradiation energy density is 400 mJ / cm or less, the laser processing performance of the cured product is improved, and the support can be efficiently peeled off. ２ , and a more preferable upper limit is 300 mJ / cm ２ Although there is no preferred lower limit to the irradiation energy density of the laser light irradiated in the support peeling step (b), the substantial lower limit is 100 mJ / cm ２ is.

[0152] The method for producing an electronic component of the present invention includes a step of curing the temporary fixing material before the support peeling step (b). The curing step preferably includes, for example, a photocuring step of curing the temporary fixing material by irradiating the temporary fixing material with light and / or a heat curing step of curing the temporary fixing material by heating the temporary fixing material.

[0153] The intensity distribution in the preferred irradiation shape of the laser light irradiated in the support peeling step (a) and the support peeling step (b) varies depending on the purpose, but it is preferably a Gaussian waveform or flattened. When the intensity distribution in the irradiation shape of the laser light irradiated in the support peeling step is a Gaussian waveform, it becomes possible to process into an even circular shape by irradiating one pulse of laser light. When the intensity distribution in the irradiation shape of the laser light irradiated in the support peeling step is flattened, there is no need to irradiate the laser light overlappingly, and the laser light can be irradiated more uniformly. Note that examples of the flattening method include methods using a splitter or a mask.

[0154] The irradiation shape of the laser light irradiated in the support peeling steps (a) and (b) is preferably rectangular. By using a rectangular irradiation shape of the laser light, the laser light can be irradiated more uniformly without gaps.

[0155] In the support peeling step (a) and the support peeling step (b), it is preferable that the entire surface of the support of the laminate is irradiated with laser light by moving a laser light irradiation device or a stage on which the laminate is placed in the vertical and horizontal directions. At this time, the laminate may be offset, and the laser light may be irradiated so as to overlap with the offset.

[0156] When laser light is irradiated in the support peeling step (a) and the support peeling step (b), white smoke may be generated. When the white smoke is generated, the laser light is blocked, and the processing performance of the laser light irradiating device is reduced. Therefore, it is preferable to ventilate the room when irradiating laser light in the support peeling step (a) and the support peeling step (b).

[0157] According to the present invention, it is possible to provide an adhesive film that can efficiently peel off a support even when irradiated with low-energy laser light, and that has excellent peelability from an adherend even when subjected to high-temperature processing. Furthermore, according to the present invention, it is possible to provide a cured product of the adhesive film. Furthermore, according to the present invention, it is possible to provide a laminate having, in this order, a support, the adhesive film, and a semiconductor. Furthermore, according to the present invention, it is possible to provide a method for producing an electronic component, which includes a step of efficiently peeling off a support even when irradiated with low-energy laser light, and a step of easily peeling off an adherend even when subjected to high-temperature processing, using the laminate. Furthermore, according to the present invention, it is possible to provide a temporary fixing material that has excellent laser processing performance and can efficiently peel off a support even when irradiated with low-energy laser light after curing. Furthermore, according to the present invention, it is possible to provide a cured product of the temporary fixing material. Furthermore, according to the present invention, it is possible to provide a laminate having the cured product. Furthermore, according to the present invention, it is possible to provide a method for producing an electronic component, which includes a step of efficiently peeling off a support even when irradiated with low-energy laser light.

[0158] The following examples will explain the present invention in more detail, but the present invention is not limited to these examples.

[0159] Synthesis Example 1: 250 ml of toluene was placed in a 500 ml round-bottom flask equipped with a Teflon (registered trademark) stirrer. 31.9 g (0.06 mol) of dimer diamine ("Priamine 1075" manufactured by Croda), 5.5 g (0.015 mol) of 2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane, and 39.8 g (0.0765 mol) of 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic anhydride were added in this order. A Dean-Stark tube and a condenser were attached to the flask, and the resulting mixture was refluxed for 6 hours and cooled to room temperature. A brown solid, polyimide A having a structural unit represented by the following formula (6-1) and a structural unit represented by the following formula (6-2), was obtained. The weight average molecular weight of the obtained polyimide A was measured by gel permeation chromatography (GPC) using THF as an eluent and an HR-MB-M (manufactured by Waters Corporation) as a column, and was found to be 78,000.

[0160]

[0161] Synthesis Example 2: 250 ml of toluene was placed in a 500 ml round-bottom flask equipped with a Teflon (registered trademark) stirrer. 56 g (0.1 mol) of dimer diamine ("Priamine 1075" manufactured by Croda) and 19.6 g (0.2 mol) of maleic anhydride were added, followed by 5 g of methanesulfonic anhydride. The resulting solution was refluxed for 12 hours, cooled to room temperature, and 300 ml of toluene was added to the flask. The solution was allowed to stand for layer separation, and the lower layer, which was an impurity, was removed. The resulting solution was filtered through a glass fritted funnel filled with silica gel, and the solvent was removed under vacuum to obtain a brown liquid bismaleimide compound D represented by the following formula (7).

[0162]

[0163] Synthesis Example 3: 250 ml of toluene was placed in a 500 ml round-bottom flask equipped with a Teflon (registered trademark) stirrer. 39.9 g (0.075 mol) of dimer diamine ("Priamine 1075" manufactured by Croda) and 39.8 g (0.0765 mol) of 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic anhydride were added in this order. A Dean-Stark tube and a condenser were attached to the flask, and the resulting mixture was refluxed for 6 hours and cooled to room temperature. A brown solid, polyimide B having a structural unit represented by formula (8) below was obtained. The weight-average molecular weight of the resulting polyimide B was measured by gel permeation chromatography (GPC) using THF as the eluent and an HR-MB-M (manufactured by Waters) column, and found to be 90,000.

[0164]

[0165] In addition, as bismaleimide C in Tables 1 to 8, a bismaleimide compound represented by the following formula (9) (manufactured by Designer Molecules, "BMI-3000GEL") was used.

[0166]

[0167] In formula (9), n is the number of repetitions.

[0168] (Synthesis of Acrylic Copolymer E) A reactor equipped with a thermometer, a stirrer, and a cooling tube was prepared. 94 parts by mass of 2-ethylhexyl acrylate, 6 parts by mass of hydroxyethyl methacrylate, 0.01 parts by mass of lauryl mercaptan, and 80 parts by mass of ethyl acetate were added to the reactor, and the reactor was heated to initiate reflux. Subsequently, 0.01 parts by mass of 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane was added as a polymerization initiator to initiate polymerization under reflux. Next, 0.01 parts by mass of 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane was added one hour and two hours after the start of polymerization, and then 0.05 parts by mass of t-hexylperoxypivalate was added four hours after the start of polymerization to continue the polymerization reaction. Then, 8 hours after the start of polymerization, an ethyl acetate solution containing a functional group-containing acrylic polymer with a solids content of 55% by mass and a weight-average molecular weight of 500,000 was obtained. 3.5 parts by mass of 2-isocyanatoethyl methacrylate was added to 100 parts by mass of the resin solids content of the obtained ethyl acetate solution containing the functional group-containing acrylic polymer, and the mixture was allowed to react to obtain acrylic copolymer D. The weight-average molecular weight of the acrylic copolymer was 550,000. The weight-average molecular weight of the obtained acrylic copolymer was measured by gel permeation chromatography (GPC, apparatus name: Acquity APC System (manufactured by Waters Corporation)) using THF as the eluent and an HR-MB-M 6.0 x 150 mm column (manufactured by Waters Corporation).

[0169] (Examples 1-1 to 1-23, Comparative Examples 1-1 to 1-7) (Preparation of Adhesive Film) Each of the materials listed in Tables 1 to 4 was added to 150 ml of toluene and mixed to prepare a toluene solution of a photocurable adhesive. The obtained toluene solution of the photocurable adhesive was applied to the release-treated surface of a 50 μm-thick release polyethylene terephthalate (PET) film that had been release-treated on one side using a doctor knife so that the thickness of the dried film was 80 μm, and the coating solution was dried by heating at 130°C for 10 minutes to obtain a laminated film. Furthermore, a 50 μm-thick release PET film that had been release-treated on one side was overlapped on the laminated film so that the release-treated surface faced the dry film, thereby obtaining an adhesive film with a release PET film.

[0170] (Gel fraction of adhesive layer) One PET film was peeled off from the obtained adhesive film, and the adhesive layer was ０ (g) The photocurable adhesive was collected and immersed in toluene at 23°C for 24 hours. After shaking, the adhesive was passed through a metal mesh (opening #200 mesh, mass: W １ The adhesive layer that had absorbed toluene and swollen was filtered using a filter (g), and the separated photocurable adhesive was dried at 110°C for 1 hour. The mass W of the adhesive layer after drying was ２ The gel fraction of the adhesive layer before light irradiation was measured by measuring the mass (g) and calculating the gel fraction using the following formula. The results are shown in Tables 1 to 2 and 4. Gel fraction (mass%) = 100 × (W ２ -W １ ) / W ０ (W ０ : Mass of the initial adhesive layer, W １ : initial mass of the metal mesh, W ２ : mass of adhesive layer including metal mesh after drying) Also, an ultra-high pressure mercury lamp was used to irradiate light with a wavelength of 405 nm at an integrated light intensity of 20,000 mJ / cm ２ After irradiating the adhesive film obtained so that the PET film on one side of the adhesive film was peeled off, the gel fraction of the adhesive layer after light irradiation was measured in the same manner as for the gel fraction of the adhesive layer before light irradiation described above. The results are shown in Tables 1 to 2 and 4.

[0171] (Extinction coefficient of adhesive layer for light with a wavelength of 308 nm) (A) Measurement of transmittance X The obtained adhesive film (adhesive layer) was cut into a flat rectangular shape of 20 mm x 30 mm, and the PET films on both sides were then peeled off to form a measurement sample, which was attached to the opening of an integrating sphere ISN-723 of a spectrophotometer V-670 (both manufactured by JASCO Corporation), and the transmittance X of light with wavelengths from 220 nm to 1500 nm was measured with the incident angle of the measurement light being 0°.

[0172] (B) Measurement of Reflectance Y An absolute reflectance measurement unit ARSN-733 (both manufactured by JASCO Corporation) was attached to a spectrophotometer V-670. The PET film on one side of the adhesive film (adhesive layer) was peeled off, and black vinyl tape (manufactured by Sekisui Chemical Co., Ltd., "Eslon Tape No. 360", black, 19 mm wide) was attached to cut back surface reflection. The PET film on the side of the adhesive film opposite to the side on which the black vinyl tape was attached was peeled off. The adhesive film was set on a sample stage using a leaf spring (an accessory to the absolute reflectance measurement unit ARSN-733) so that measurement light was incident from the side opposite to the side on which the black vinyl tape was attached, and the reflectance Y of light with wavelengths from 220 nm to 1500 nm was measured with an incident angle of 5° and a reflection angle of 5° for the measurement light.

[0173] (C) Measurement of adhesive layer thickness The PET films on both sides of the adhesive film (adhesive layer) were peeled off, and the thickness of the adhesive layer was measured using a thickness meter (Mitutoyo Corporation, "Digimatic Indicator ID-H").

[0174] (D) Derivation of extinction coefficient Using the measured transmittance X, reflectance Y, and adhesive layer thickness, the refractive index n and extinction coefficient k were analyzed using spectroscopic ellipsometry analysis software (J.A. Woollam, "WVASE32"). By approximating the refractive index in the visible range (wavelength 380 nm or more and 780 nm or less) with Cauchy's polynomial, the value of the refractive index n1 from the absorption edge to a wavelength of 780 nm was obtained using the transmittance X. The obtained refractive index n1 was fixed and used as the refractive index of light with a wavelength of 220 nm to 1500 nm, and the extinction coefficient k1 was calculated using the transmittance X. Furthermore, the reflectance y1 was calculated using the calculated refractive index n1 and extinction coefficient k1. Since the reflection of light on the adhesive layer surface is not a perfect specular reflection, the measured reflectance Y is lower than the ideal reflectance, so the reflectance Y in the visible range was adjusted to match the reflectance y1 and set as the reflectance y2. Next, the extinction coefficient k1 was fixed and the refractive index n2 was calculated from wavelengths of 220 nm to 1500 nm using the reflectance y2. This procedure was repeated until the measured and calculated reflectance values ​​matched, and the refractive index n and extinction coefficient k from wavelengths of 220 nm to 1500 nm were determined. In the present examples and comparative examples, except for Comparative Examples 1-4, the transmittance at a wavelength of 308 nm was 1% or less. Therefore, it was assumed that the extinction coefficient in the long wavelength region (extinction coefficient from wavelengths of 395 nm to 425 nm) where the transmittance was greater than 1% was used to approximate an exponential function, and the equation of the approximate curve (y = A (constant) × e^(B (constant) × x), y: extinction coefficient, x: wavelength (nm)) was determined by the least squares method. The extinction coefficient k at a wavelength of 308 nm was determined from the equation of the obtained approximate curve. When the wavelength at which the transmittance was 1% or less was shorter than 308 nm, the extinction coefficient k at a wavelength of 308 nm was determined from the above analysis results. Since the transmittance at a wavelength of 308 nm in Comparative Example 1-4 was over 1%, the extinction coefficient k at a wavelength of 308 nm was calculated from the above analysis results. The extinction coefficient of the adhesive layer for light with a wavelength of 308 nm before light irradiation was calculated from the above analysis. The results are shown in Tables 1-2 and 4.

[0175] Furthermore, the obtained adhesive film (adhesive layer) was irradiated with light of a wavelength of 405 nm from an ultra-high pressure mercury lamp until the cumulative light intensity reached 20,000 mJ / cm ２After irradiating the adhesive layer with light, the extinction coefficient for light with a wavelength of 308 nm after irradiation was measured using the same methods as those described above in "(A) Measurement of transmittance X," "(B) Measurement of reflectance Y," "(C) Measurement of thickness of adhesive film," and "(D) Derivation of extinction coefficient." The results are shown in Tables 1 to 2 and 4.

[0176] (5% weight loss temperature when the adhesive film is heated at a temperature increase rate of 10°C / min in a nitrogen atmosphere after light irradiation) The obtained adhesive film was cut into a flat rectangular shape of 100 mm x 200 mm, and then irradiated with light of a wavelength of 405 nm from an ultra-high pressure mercury lamp at an integrated light intensity of 20,000 mJ / cm ２ The adhesive film cut so as to be irradiated with light was weighed into an aluminum pan, the PET films on both sides of the adhesive film were peeled off, and the aluminum pan was set in a thermogravimetric differential thermal analyzer ("STA7200" manufactured by Hitachi High-Tech Science Corporation), and then thermogravimetric analysis was performed in a nitrogen atmosphere at a heating rate of 10 ° C. / min. The temperature at which the weight of the adhesive film became 95% of the initial weight was taken as the 5% weight loss temperature when the adhesive film was heated at a heating rate of 10 ° C. / min in a nitrogen atmosphere after light irradiation, and the results are shown in Tables 1 to 2 and 4.

[0177] <Evaluation> The adhesive films obtained in Examples 1-1 to 1-23 and Comparative Examples 1-1 to 1-7 were evaluated as follows. The results are shown in Tables 1 to 4.

[0178] (Preparation of Laminate) One release PET film was peeled off from the obtained adhesive film, and the film was attached to a silicon wafer having a diameter of 200 mm and a thickness of 700 μm under vacuum and 40° C. conditions, and the adhesive film was cut to the shape of the silicon wafer. Next, the other release PET film from the attached adhesive film was peeled off, and a glass sheet having a diameter of 200 mm and a thickness of 600 μm (manufactured by SCHOTT, "Tempax") was attached to the surface opposite to the surface attached to the silicon wafer under vacuum and 90° C. conditions using a pressure lamination device (manufactured by Takatori, "GWSM-300M") to obtain a laminate. In addition, an ultra-high pressure mercury lamp was used to irradiate the glass side of the obtained laminate with light having a wavelength of 405 nm at an integrated light intensity of 20,000 mJ / cm. ２and a heating treatment was carried out for 30 minutes using a hot plate (manufactured by MSA Factory, "PH224 / 225") at 290°C under a nitrogen atmosphere.

[0179] (Removability of Support) After the above-described light irradiation treatment and heat treatment were performed and the laminate was naturally cooled, a wavelength of 308 nm and an irradiation energy density of 250 mJ / cm were applied from the glass side. ２ A pulsed laser with a pulse width of 20 nsec was irradiated onto the entire glass surface. Thereafter, the silicon wafer side was fixed to an adsorption stage, a suction cup hook was attached to the glass side, and a digital force gauge (Imada Co., Ltd., "ZTS-50N") was hooked onto the hook. In this way, the peel force to peel the glass from the adhesive film was measured with the digital force gauge. The peelability of the support was evaluated by rating a peel force of 20 N / inch or less as "◎", a peel force of more than 20 N / inch but not more than 30 N / inch as "◯", and a peel force of more than 30 N / inch as "×".

[0180] (Releasability of adhesive film) For the laminate after peeling of the support used in the above-mentioned "(Releasability of support)", the adhesive film on the laminate was cut to a width of 25 mm, and the adhesive film was peeled from the semiconductor device using a tensile tester (manufactured by Shimadzu Corporation, "AG-IS") at a peel speed of 300 mm / min and a peel angle of 180°, thereby measuring the 180° peel strength of the adhesive film. The releasability of the adhesive film was evaluated by rating it as "○" when the obtained 180° peel strength was 1.0 N / inch or less, "△" when it was more than 1.0 N / inch and 3.0 N / inch or less, and "×" when it was more than 3.0 N / inch.

[0181] (Examples 1-24 to 1-26) (Preparation of adhesive film) Two laminated films were prepared in the same manner as in Examples 1-1 to 1-23 and Comparative Examples 1-1 to 1-7, and then one laminated film was placed on each of the two surfaces of the substrate shown in Table 3 so that the dry coatings faced each other, thereby obtaining an adhesive film having a substrate and adhesive layers having the same composition and thickness on both sides of the substrate.

[0182] The types of substrates shown in Table 3 are as follows: PA (polyamide)-containing substrate (UNIAMID (registered trademark) manufactured by Unitika Ltd.) Transparent PI (polyimide)-containing substrate (TORMED (registered trademark) manufactured by IST Co., Ltd.) PEEK (polyether ether ketone)-containing substrate (EXPEEK manufactured by Kurabo Industries, Ltd.)

[0183] (Gel fraction of adhesive layer) The gel fraction of the adhesive layer before and after light irradiation was obtained in the same manner as in Examples 1-1 to 1-23 and Comparative Examples 1-1 to 1-7. The results are shown in Table 3.

[0184] (Extinction coefficient of adhesive layer for light with a wavelength of 308 nm) A cutter knife was inserted between the substrate and the adhesive layer in the obtained adhesive film to separate the substrate and the adhesive layer. The transmittance X, reflectance Y, and thickness of the separated adhesive layer were measured using the same methods as in Examples 1-1 to 1-23 and Comparative Examples 1-1 to 1-3, and 1-5 to 1-7, and the extinction coefficient was calculated. The results are shown in Table 3.

[0185] (5% weight loss temperature when heated at a temperature increase rate of 10°C / min in a nitrogen atmosphere after light irradiation of the adhesive film) In the same manner as in Examples 1-1 to 1-23 and Comparative Examples 1-1 to 1-7, the 5% weight loss temperature when heated at a temperature increase rate of 10°C / min in a nitrogen atmosphere after light irradiation of the adhesive film was measured. The results are shown in Table 3.

[0186] The evaluation was carried out in the same manner as in Examples 1-1 to 1-23 and Comparative Examples 1-1 to 1-7. The results are shown in Table 3.

[0187]

[0188]

[0189]

[0190]

[0191] (Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16, Comparative Examples 2-1 to 2-2) (Preparation of Temporary Fixing Material) Each of the materials listed in Tables 5 to 6 and 8 was added to 150 mL of toluene and mixed to prepare a toluene solution of a curable adhesive. The obtained toluene solution of the curable adhesive was applied to the release-treated surface of a 50 μm-thick release polyethylene terephthalate (PET) film that had been release-treated on one side with a doctor knife so that the thickness of the dried film was 80 μm, and the coating solution was dried by heating at 130 °C for 10 minutes to obtain a laminated film. Furthermore, a 50 μm-thick release PET film that had been release-treated on one side was overlapped on the laminated film so that the release-treated surface faced the dry film, thereby obtaining a temporary fixing material with a release PET film.

[0192] (Laser processing depth after hardening of temporary fixing material) One release PET film was peeled off from the obtained temporary fixing material, and the temporary fixing material was attached to a silicon wafer having a diameter of 200 mm and a thickness of 700 μm under vacuum conditions at 40° C. The temporary fixing material was then cut into the shape of the silicon wafer. Ultraviolet light with a wavelength of 365 nm was irradiated from an ultra-high pressure mercury lamp from the side of the other release PET film of the temporary fixing material attached to the silicon wafer, with an integrated light intensity of 20,000 mJ / cm. ２ After further irradiation with ultraviolet light, the other release PET film was peeled off, and the temporary fixing material was cured by heating for 30 minutes under a nitrogen atmosphere using a hot plate (manufactured by MSA Factory, "PH224 / 225") at 290°C. The cured temporary fixing material was then irradiated with ultraviolet light at a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm. ２ After the laser beam pulse irradiation, the surface of the cured product on the laser beam irradiated side was measured for step height using a laser microscope (manufactured by Olympus Corporation, "OLS4100-SAT", wavelength 405 nm) to measure the laser processing depth. ２ The laser processing depth when irradiated with laser light of 1000 kJ / cm was also measured in the same manner. The obtained laser processing depths are shown in Tables 5 to 6 and 8.

[0193] (Weight loss rate when the temporary fixing material is heated at 290°C for 30 minutes in a nitrogen atmosphere after hardening) The obtained temporary fixing material was irradiated with ultraviolet light of 365 nm wavelength from an ultra-high pressure mercury lamp at an integrated light intensity of 20,000 mJ / cm ２ After irradiation so that the temporary fixing material was cured, the temporary fixing material was subjected to a heat treatment for 30 minutes using a hot plate (manufactured by MSA Factory, "PH224 / 225") at 290°C in a nitrogen atmosphere. One of the release PET films of the cured temporary fixing material was peeled off, and the cured temporary fixing material was removed to a mass W ５ (mg) The sample was weighed into an aluminum pan, and the aluminum pan was set in a thermogravimetric and differential thermal analyzer ("STA7200" manufactured by Hitachi High-Tech Science Corporation). After that, the sample was heated at 290°C for 30 minutes in a nitrogen atmosphere, and the weight W of the hardened temporary fixing material was measured. ６ The weight loss rate (%) was calculated using the following formula. The results are shown in Tables 5 to 6 and 8. Weight loss rate (%) = 100 × (W ５ -W ６ ) / W ５

[0194] <Evaluation> The temporary fixing materials obtained in Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16 and Comparative Examples 2-1 to 2-2 were evaluated as follows. The results are shown in Tables 5 to 6 and 8.

[0195] (Preparation of Laminate) One release PET film of the obtained temporary fixing material was peeled off, and the temporary fixing material was attached to a silicon wafer having a diameter of 200 mm and a thickness of 700 μm under vacuum and 40°C conditions using a vacuum laminator (manufactured by Takatori Corporation, "ATM-812M"), and the temporary fixing material was cut into the shape of the silicon wafer. Next, the other release PET film of the attached temporary fixing material was peeled off, and a glass sheet having a diameter of 200 mm and a thickness of 600 μm (manufactured by SCHOTT, "Tempax") was attached to the surface opposite to the surface attached to the silicon wafer under vacuum and 90°C conditions using a pressure lamination device (manufactured by Takatori Corporation, "GWSM-300M"). From the glass side of the temporary fixing material attached to the silicon wafer and glass, ultraviolet light with a wavelength of 365 nm was irradiated using an ultra-high pressure mercury lamp, with an integrated light intensity of 20,000 mJ / cm. ２After irradiation so as to obtain a laminate, the laminate was heated for 30 minutes in a nitrogen atmosphere using a hot plate (manufactured by MSA Factory, "PH224 / 225") at 290°C.

[0196] (Laser lift-off evaluation) The obtained laminate was irradiated from the glass side with a laser having a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm. ２ The entire glass surface was irradiated with pulsed laser light. Thereafter, the silicon wafer side of the laminate was fixed to an adsorption stage, a suction cup hook was attached to the glass side of the laminate, and a digital force gauge (Imada Co., Ltd., "ZTS-50N") was hooked onto the hook. In this way, the peel force peeling the glass from the cured product was measured with a digital force gauge, and laser lift-off evaluation was performed. The support peeling performance of the cured product was evaluated by assigning "◎" when the obtained peel force was 20 N / inch or less, "◯" when it was more than 20 N / inch and 30 N / inch or less, and "×" when it was more than 30 N / inch.

[0197] Examples 2-3 to 2-5 Temporary fixing materials and laminates were prepared and evaluated in the same manner as in Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16, and Comparative Examples 2-1 to 2-2, except that the step of irradiating with ultraviolet light having a wavelength of 365 nm was not performed in the above-mentioned "(Laser processing depth after hardening of the temporary fixing material)," "(Weight loss rate when heated at 290°C for 30 minutes in a nitrogen atmosphere after hardening of the temporary fixing material)," and "(Preparation of laminate)." The results are shown in Table 5.

[0198] Example 2-6 Temporary fixing materials and laminates were prepared and evaluated in the same manner as in Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16, and Comparative Examples 2-1 to 2-2, except that the heat treatment step after ultraviolet irradiation was not performed in the above-mentioned "(Laser processing depth after hardening the temporary fixing material)," "(Weight loss rate when heated at 290°C for 30 minutes in a nitrogen atmosphere after hardening the temporary fixing material)," and "(Preparation of laminate)." The results are shown in Table 6.

[0199] (Example 2-9) In the above-mentioned "(Laser processing depth after hardening of temporary fixing material)", "(Weight reduction rate when heated at 290°C for 30 minutes in a nitrogen atmosphere after hardening of temporary fixing material)", and "(Fabrication of laminate)", an LED was used instead of an ultra-high pressure mercury lamp, and ultraviolet light with a wavelength of 365 nm was irradiated at an integrated light intensity of 20,000 mJ / cm. ２ Temporary fixing materials and laminates were prepared and evaluated in the same manner as in Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16 and Comparative Examples 2-1 to 2-2, except that irradiation was performed so that the temperature was 100°C. The results are shown in Table 5.

[0200] (Example 2-17) Measurement of the laser processing depth after curing the temporary fixing material was carried out using a laminate having the cured temporary fixing material and a support. The obtained temporary fixing material was heat-laminated onto quartz using a thermal laminator ("Leon 13DX" manufactured by Lamy Corporation) at 100°C and speed setting 3. Thereafter, the temporary fixing material was cured in the same manner as in Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16, and Comparative Examples 2-1 to 2-2, and the obtained laminate was subjected to irradiation with a wavelength of 308 nm, a pulse width of 10 nsec, and an irradiation energy density of 300 mJ / cm. ２ After irradiating the quartz side with a laser beam of 400 mJ / cm, the laser processing depth was measured in the same manner as above. ２ The laser processing depth when irradiated with laser light of 1000 nm was also measured in the same manner. The preparation of the temporary fixing material and the laminate, the measurement of the weight loss rate after curing the temporary fixing material, and the laser lift-off evaluation were carried out in the same manner as in Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16, and Comparative Examples 2-1 to 2-2. The results are shown in Table 6.

[0201] (Examples 2-18 to 2-28) In the above-mentioned "(Laser processing depth after hardening of temporary fixing material)", "(Weight reduction rate when heated at 290°C for 30 minutes in a nitrogen atmosphere after hardening of temporary fixing material)", and "(Fabrication of laminate)", ultraviolet rays with a wavelength of 405 nm were irradiated using an ultra-high pressure mercury lamp at an integrated light intensity of 20,000 mJ / cm. ２Temporary fixing materials and laminates were prepared and evaluated in the same manner as in Examples 2-1 to 2-2, 2-7 to 2-8, 2-10 to 2-16 and Comparative Examples 2-1 to 2-2, except that irradiation was performed so that the temperature was 100°C. The results are shown in Tables 6 and 7.

[0202]

[0203]

[0204]

[0205]

[0206] According to the present invention, it is possible to provide an adhesive film that can efficiently peel off a support even when irradiated with low-energy laser light, and that has excellent peelability from an adherend even when subjected to high-temperature processing. Furthermore, according to the present invention, it is possible to provide a cured product of the adhesive film. Furthermore, according to the present invention, it is possible to provide a laminate having, in this order, a support, the adhesive film, and a semiconductor. Furthermore, according to the present invention, it is possible to provide a method for producing an electronic component, which includes a step of efficiently peeling off a support even when irradiated with low-energy laser light, and a step of easily peeling off an adherend even when subjected to high-temperature processing, using the laminate. Furthermore, according to the present invention, it is possible to provide a temporary fixing material that has excellent laser processing performance and can efficiently peel off a support even when irradiated with low-energy laser light after curing. Furthermore, according to the present invention, it is possible to provide a cured product of the temporary fixing material. Furthermore, according to the present invention, it is possible to provide a laminate having the cured product. Furthermore, according to the present invention, it is possible to provide a method for producing an electronic component, which includes a step of efficiently peeling off a support even when irradiated with low-energy laser light.

Claims

1. An adhesive film including an adhesive layer containing a curable adhesive, the curable adhesive is a photocurable adhesive, The adhesive layer is irradiated with light having a wavelength of 405 nm with an integrated light amount of 20,000 mJ / cm ２ The gel fraction after irradiation is 65% by mass or more, The adhesive layer is irradiated with light having a wavelength of 405 nm with an integrated light amount of 20,000 mJ / cm ２ After irradiation so that the extinction coefficient for light with a wavelength of 308 nm is 1.0×10 －４ That's all. An adhesive film characterized by:

2. An adhesive film including an adhesive layer containing a curable adhesive, the curable adhesive is a photocurable adhesive, the adhesive layer has a gel fraction of 65% by mass or more after light irradiation, The adhesive layer has an extinction coefficient of 1.0×10 for light having a wavelength of 308 nm after irradiation with light. －４ That's all. An adhesive film characterized by:

3. 3. The adhesive film according to claim 1, wherein the curable adhesive comprises a curable resin and a photopolymerization initiator.

4. 4. The adhesive film according to claim 3, wherein the curable resin comprises a bismaleimide compound.

5. 4. An adhesive film according to claim 3, wherein the photopolymerization initiator has an absorption coefficient of 10 ml / (g·cm) or more at a wavelength of 405 nm.

6. 4. The adhesive film according to claim 3, wherein the content of the photopolymerization initiator is 0.1 parts by mass or more and 10 parts by mass or less based on 100 parts by mass of the curable resin.

7. 4. The adhesive film according to claim 3, wherein the curable adhesive further contains an ultraviolet absorbing agent.

8. The adhesive film according to claim 7 , wherein the ultraviolet absorbing agent comprises a triazine-based ultraviolet absorbing agent.

9. 8. The adhesive film according to claim 7, wherein the content of the ultraviolet absorbing agent is from 1 part by mass to 30 parts by mass with respect to 100 parts by mass of the curable resin.

10. 4. The adhesive film according to claim 3, wherein the curable adhesive further contains a release agent.

11. The adhesive film according to claim 10 , wherein the release agent comprises at least one selected from the group consisting of silicone-based release agents and acrylic-based release agents.

12. 11. The adhesive film according to claim 10, wherein the content of the release agent is 0.1 parts by mass or more and 20 parts by mass or less based on 100 parts by mass of the curable resin.

13. 3. The adhesive film according to claim 1, wherein the adhesive layer has a gel fraction of 60% by mass or less before being irradiated with light.

14. The adhesive layer has an extinction coefficient of 1.0×10 for light with a wavelength of 308 nm before irradiation with light. －４ The adhesive film according to claim 1 or 2.

15. 3. The adhesive film according to claim 1, which has a substrate.

16. The integrated light intensity of 405 nm wavelength light is 20,000 mJ / cm ２ 3. An adhesive film according to claim 1, which has a 5% weight loss temperature of 300° C. or higher when heated in a nitrogen atmosphere at a temperature increase rate of 10° C. / min after irradiation so as to satisfy the above condition.

17. 3. The adhesive film according to claim 1, which is used for temporarily fixing electronic parts.

18. A cured product obtained by curing the adhesive film according to claim 1 or 2, Wavelength 308 nm, pulse width 10 nsec, irradiation energy density 300 mJ / cm ２The cured product has a laser processing depth of 0.10 μm or more when irradiated with pulsed laser light.

19. 3. A laminate comprising a support, the adhesive film according to claim 1 or 2, and a semiconductor device, in that order.

20. Using the laminate according to claim 19, a light irradiation step of irradiating the laminate with light from the support side; A high-temperature processing step of subjecting the laminate to a heat treatment or a treatment involving heat generation; a support peeling step of irradiating the laminate with laser light having a wavelength of 200 nm or more and 355 nm or less from the support side to peel the support from the adhesive film; and An adhesive film peeling step of peeling the adhesive film from the semiconductor device. A method for manufacturing an electronic component having the above structure.

21. A temporary fixing material containing a curable adhesive, the curable adhesive is a photocurable adhesive, The integrated light intensity of 365 nm wavelength light is 20,000 mJ / cm ２ After curing, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm. ２ When pulsed laser light is applied, the laser processing depth is 0.10 μm or more. A temporary fixing material characterized by:

22. A temporary fixing material containing a curable adhesive, After curing, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２ When pulsed laser light is applied, the laser processing depth is 0.10 μm or more. A temporary fixing material characterized by:

23. After curing, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 300 mJ / cm ２23. The temporary fixing material according to claim 21 or 22, wherein the laser processing depth when pulsed with a laser beam is 1.0 μm or less.

24. After the curing, the wavelength was 308 nm, the pulse width was 10 nsec, and the irradiation energy density was 400 mJ / cm ２ 23. The temporary fixing material according to claim 21 or 22, wherein the laser processing depth when pulsed with a laser beam is 1.0 μm or less.

25. The temporary fixing material according to claim 21 or 22, wherein the curable adhesive contains a curable resin, and the curable resin contains a resin having an imide skeleton in a repeating unit of a main chain.

26. The temporary fixing material according to claim 25, wherein the content of the resin having an imide skeleton in a repeating unit of a main chain is 65 parts by mass or more in 100 parts by mass of the curable resin.

27. The temporary fixing material according to claim 21 or 22, wherein the curable adhesive contains an ultraviolet absorbing agent or an ultraviolet scattering agent.

28. The temporary fixing material according to claim 27 , wherein the ultraviolet absorbing agent or the ultraviolet scattering agent contains a triazine-based ultraviolet absorbing agent or titanium oxide.

29. The temporary fixing material according to claim 21 or 22, wherein the curable adhesive contains a photopolymerization initiator.

30. 23. The temporary fixing material according to claim 21 or 22, which has a weight loss rate of 7% or less when heated at 290° C. for 30 minutes in a nitrogen atmosphere after curing.

31. A cured product obtained by curing the temporary fixing material according to claim 21 or 22.

32. A method for manufacturing a semiconductor device comprising the steps of: a support; the cured product according to claim 31; and a semiconductor device, in this order; The support has a transmittance of 50% or more for light having a wavelength of 300 nm or more and 400 nm or less. The laminate is

33. A laminate including a support, the cured product according to claim 31, and a semiconductor device in this order, Wavelength: 308 nm to 355 nm, pulse width: 100 nsec or less, irradiation energy density: 500 mJ / cm ２ A method for manufacturing an electronic component, comprising a support peeling step of peeling the support from the laminate by irradiating the support with pulsed laser light as follows: